## Research Collaboration

The department engages research collaboration with National and international Universities and research institutes in various fields of chemical and allied Sciences like University of Bologna, Italy; University of Milan, Italy; University of Milano-Bicocca, Milan, Italy; Colarado State University, USA; Council of National Research, Milan; NCL, Pune;  IIT, Hyderabad, Chennai, Gandhinagar, IIST, NIIST, IISER Thiruvananthapuram, IGCAR, Kalpakkam, etc.

## RESEARCH FACILITIES

Amrita Vishwa Vidyapeetham has provided all infrastructure which in turn provide a conducive physical ambience for research in terms of adequate research laboratories, computing facilities and allied services. The department also possesses classical chemistry labs which have been structured with a vision of transforming it into an excellent centre for research in the frontier areas of applied chemistry and allied branches. The research lab is well equipped with various sophisticated equipments which help in carrying out research in the various frontier as well as emerging areas in chemistry.

## STUDENT INTERNSHIPS

We send our students for short term internships and final projects to premier research institutes and Universities in India and abroad like IITs at Mumbai, Chennai, Guhawti, CSIR Labs, CLRI, NCL, SIKRI, JNCASR, Tokyo Metropolitan University, Monash University. Many of our students and alumini got admission to pursue their higher studies in prestigious institutions like IIT, NIT.

## HIGHER STUDIES & RESEARCH OPPORTUNITIES

Special training are given to the students to write GATE, NET and IAS exams for their higher studies. Students are encouraged to take up the Integrated PhD / PhD programmes in India and abroad.

## Publications

### Publication Type: Journal Article

Year of Publication Publication Type Title

2021

Journal Article

R. Rejithamol, Krishnan, R. G., and Dr. Beena S., “Disposable pencil graphite electrode decorated with a thin film of electro-polymerized 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido [1, 2-a] azepine for simultaneous voltammetric analysis of dopamine, serotonin and tryptophan”, Materials Chemistry and Physics, vol. 258, p. 123857, 2021.[Abstract]

A facile electrochemical sensor for the individual and simultaneous quantification for elevated levels of dopamine, tryptophan, and serotonin was fabricated on pencil graphite electrode modified with 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine. The fabricated electrode was characterized by scanning electron microscopy and infrared spectroscopy. Voltammetric response of dopamine, tryptophan and serotonin on the electrode was attained by cyclic and differential pulse voltammetric techniques. Under experimental conditions, three well-separated irreversible oxidation peaks at +0.123 V, +0.302 V and +0.619 V were observed correspond to the oxidations of dopamine, serotonin and tryptophan. The anodic peak currents and the concentrations of dopamine, serotonin, and tryptophan were found to be linear in the range from 1 to 20 μM, 1–62 μM, and 1.5–750 μM with detection limits of 0.05, 0.27, and 0.05 μM, respectively. The linear ranges and the limits of detection for the simultaneous determination of these analytes are found to be superior to previously reported electrochemical sensors. The electropolymerization of 2, 3, 4, 6, 7, 8, 9, 10-octahydropyrimido[1, 2-a] azepine on a pencil graphite electrode is reported for the first time and the fabricated electrode is suitable for the determination of dopamine, serotonin and tryptophan in human blood and urine samples with good reproducibility and stability.

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2021

Journal Article

Rini John, Pal, K., Jitha S Jayan, Dr. Saritha A., and Kuruvilla Joseph, “New emerging review on advances in block copolymer based water purification membranes”, Journal of Molecular Structure, vol. 1231, p. 129926, 2021.[Abstract]

Membrane technology enables the use of membranes as filters in a wide array of separation processes leading to various applications. Nano filtration membrane is the choice of most of the studies due to its excellent efficiency for the softening of water and also its ability to remove heavy metals. Though polymers and composites are widely employed as Nano filtration membranes, there is very limited work in the area of block copolymer based Nano composite/membranes/blends and hence the present review concentrates on this aspect. This review also includes a comprehensive discussion on di and tri block copolymers (BCPs) along with their blends and composite membranes in the area of water purification. This review also discusses about the various techniques that are employed for the fabrication of BCP based membrane and its characteristics. Tuning of pore size and its efficiency in water purification are discussed in a comprehensive manner. Compared to the existing reviews, this review gives an overview about the efficiency of BCP blends and composites in water purification.

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2021

Journal Article

J. S. Jayan, Pal, K., Dr. Saritha A., Deeraj, B. D. S., and Kuruvilla Joseph, “Graphene oxide as multi-functional initiator and effective molecular reinforcement in PVP/epoxy composites”, Journal of Molecular Structure, vol. 1230, p. 129873, 2021.[Abstract]

In this work, grafting of Polyvinylpyrrolidone (PVP) onto the surface of Graphene Oxide (GO) by following the ‘grafting from’ technique was carried out by the GO-initiated cationic polymerization of N-Vinylpyrrolidone monomers. The successful grafting of PVP onto GO sheets was confirmed with the help of various techniques like FTIR, XRD, Raman and XPS. The PVP polymer chain grafted GO (GO-g-PVP) was incorporated into the epoxy matrix as a reinforcement in order to investigate the effect in thermo-mechanical properties of epoxy. From static mechanical testing, it was observed that neat PVP adversely affects the mechanical (tensile) strength of epoxy, whereas the GO-g-PVP shows an improvement of about 13% when compared to the virgin epoxy composites. Rheological data reveals the transformation of epoxy resin from the Newtonian behavior to shear thickening nature by the incorporation of GO-g-PVP. Dynamic mechanical analysis and the intensity of tan δ curves also ratify the rheological observation. The fracture toughness of epoxy composites showed a significant improvement of about 190% than the neat epoxy composites. Electron microscopes are employed to observe the Fractograms to systematically analyze the toughening mechanisms involved. Thermal stability and the temperature of glass transitions were optimized by TGA and DSC analysis.

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2021

Journal Article

S. P. S., Jayan, J. S., Dr. Saritha A., V., S. Babu, and G., S., “Effect of TiO2 grain size on performance of Ba0.5Sr0.5TiO3 based capacitors for energy storage application”, Micro & Nano Letters, vol. 16, pp. 239-244, 2021.[Abstract]

Performance of energy storage devices, particularly metal-insulator-metal capacitors are evaluated mainly by leakage current and specific capacitance. The insulator material Ba0.5Sr0.5TiO3 shows high specific capacitance owing to its high relative permittivity. In this work, Ba0.5Sr0.5TiO3 nanopowder is synthesized using commercially available TiO2 nanopowder (ACS reagent grade) as well as using synthesized TiO2 nanopowder from Ti isopropoxide. The crystallinity and grain sizes of commercially available and synthesized TiO2 nanopowder differ. The effects of crystallinity and grain size of TiO2 nanopowder on specific capacitance and leakage current density of Ba0.5Sr0.5TiO3 ceramic based metal-insulator-metal capacitors are investigated in this paper. An 88 % reduction in grain size is achieved in TiO2 nanopowder synthesized from Ti isopropoxide compared to commercially available TiO2 nanopowder. A 45 % enhancement in specific capacitance and 57 % enhancement in leakage current are achieved in Ba0.5Sr0.5TiO3 ceramic based metal-insulator-metal capacitor synthesized using TiO2 nanopowder with lower grain size. The lower leakage current of metal-insulator-metal capacitor with Ba0.5Sr0.5TiO3 ceramic of low grain size is investigated with its structure using X-ray powder diffraction pattern analysis as well. The Ba0.5Sr0.5TiO3 ceramics synthesized using TiO2 nanopowder with lower grain size is a suitable candidate for insulator material in metal-insulator-metal capacitors for energy storage application.

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2021

Journal Article

P. G, AS, S., Jitha S Jayan, Raman, A., and Dr. Saritha A., “Lignin based nano-composites: Synthesis and applications”, Process Safety and Environmental Protection, vol. 145, pp. 395-410, 2021.[Abstract]

The development of bio-based nanocomposites is of extreme significance in the current environmental situation and hence the progression as well as modification of lignin based nanocomposites is gaining potential research interest. Often treated as a wood waste, lignin is generated as an unwanted component during the production of ethanol and paper. Being a biopolymer with cross-linked structure and an imperative renewable material with antioxidant property, high thermal stability, biodegradability and UV absorption characteristics, lignin could be effectively employed in numerous prospective applications. Introducing various functionalities into lignin transforms it into a valuable material in the composite arena. The key aim of this review is to summarize the synthesis methods and functionalization of lignin nano particles along with the applications of lignin based nanocomposites thereby creating awareness towards the sustainable utilization of waste lignin in the environment.

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2021

Journal Article

K. Sivaselvi, Varma, V. S., Harikumar, A., Jayaprakash, A., Sankar, S., C. Krishna, Y., and Dr. Gopal K., “Improving the mechanical properties of natural rubber composite with carbon black (N220) as filler”, Materials Today: Proceedings, vol. 42, pp. 921-925, 2021.[Abstract]

Rubber is one of the most commonly employed materials in the whole world. Earlier rubber obtained from natural resources was widely used. However, as industries grew tremendously, many new products were introduced to the world and rubber can be used for almost all the practical applications including as windshield wiper blade in automobiles. Most of the windshield wiper blade are made of synthetic rubber. Our research is focused to replace the synthetic compounds in wiper blade with natural materials which will be durable and eco-friendly. Natural rubber, treated with Carbon black (N220) as fillers and Silica in the presence of vulcanizing agents and other organic additives, works much more efficiently. Sulphur was replaced with Xanthate and soybean oil was used instead of petroleum products during vulcanization. The mechanical properties were investigated by various composition of Carbon black (N220) and silica. The tension test, abrasion test, and wear test were studied for different five compositions.

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2021

Journal Article

G. Reshma, Varadha Padmanabhan, Varma, A. R., Gouri, M. S., Nair, U. R., Parvathy, P. B., Dr. Naveen V. Kulkarni, and Senthurpandi, D., “Synthesis and structure of mono and bis 1,3-bis(2- pyridylimino)isoindoline supported 3d transition metal complexes”, Journal of Molecular Structure, vol. 1226, p. 129344, 2021.[Abstract]

Series of homoleptic and heteroleptic 3d transition metal complexes were prepared in analytically pure form and high yield, by reacting appropriate metal precursors with 1,3-bis(2-pyridylimino)isoindolate (BPIH) ligand under suitable reaction conditions. The complexes were characterized by various spectro-analytical techniques, including IR, UV, NMR, ESI Mass and X-ray crystal analysis. A distorted octahedral structure containing two meridionally coordinating BPI ligands was assigned to all the homoleptic complexes. While, for the heteroleptic complexes, a highly distorted square pyramidal geometry, with a planar tridentate BPI ligand coordinating to the metal center along with chloro and aqua ligands was assigned. Considering the unique structural features of the complexes, potential catalytic applications are envisaged.

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2021

Journal Article

S. Hema, Krishnan, A., Akther, A., Suresh, A., Sreedha Sambhudevan, and Balakrishnan Shankar, “Green nanocomposites based on natural rubber latex containing xylan from sugarcane bagasse – Synthesis, characterization and dye absorption studies”, Materials Today: Proceedings, 2021.[Abstract]

Natural rubber latex is exceptionally resistant to wear and tear, possess great tensile strength, elongation and resilience, and has high hydrophobicity and film forming character. These combined properties make them a good candidate for dye absorption purpose. The elimination of colour from dye-tainted wastewaters in the textile, dyeing, printing and other related industries has been a crucial hitch to environment. The membrane processes are considered as the simple and effective method to remove dyes than any other methods. Natural rubber latex was mixed with xylan nanopowder extracted from sugarcane bagasse to develop thin films of good porosity. Xylan powder synthesized was characterized using Fourier Transform Infrared (FTIR) Spectroscopy and X-Ray Diffraction studies (XRD). Scanning Electron microscopy (SEM) studies were done to examine the distribution xylan particles in latex matrix. UV–Visible spectroscopy was used to study the dye absorption. Results shows that xylan prepared are in the nano regime and could be evenly distributed in latex film. The films show exceptional dye absorption properties for both methylene blue and malachite green.

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2021

Journal Article

G. S. Gopika, Prasad, P. M. Hari, Lekshmi, A. G., Lekshmypriya, S., Sreesaila, S., Arunima, C., Kumar, M. S., Anil, A., Sreekumar, A., and Dr. Zeena S. Pillai, “Chemistry of cyanine dyes-A review”, Materials Today: Proceedings, 2021.[Abstract]

Compounds which impart colour is usually referred to as dyes. Based on the difference in the structure they are classified into apocyanines, cyanines, hemicyanines, etc. Owing to the numerous applications in the field of medicine, science and technology, cyanine dyes occupy an indispensable position among dyes and pigments. They are put to use in various ways - as synthetic drugs, photoreceptors, cell growth inhibitors, fluorescent sensors, photorefractive materials etc. Considerable amount of work has been carried out based on the syntheses and applications of cyanine dyes. This review throws light on the structure and classification of cyanine dyes along with its syntheses, aggregation properties and applications.

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2021

Journal Article

H. Krishnan, Leema, M., Gopika, G. S., Prasad, P. M. Hari, Rajan, A., Anil, A., Dev, A. P., and Dr. Zeena S. Pillai, “SARS CoV-2: Progression and treatment protocols – An overview”, Materials Today: Proceedings, 2021.[Abstract]

COVID-19 pandemic is a global health crisis which has affected citizens of all nations. With more than a million death cases, this outbreak has already had a significant impact on the physical and mental wellbeing of mankind. Considerable amount of research is going on worldwide to find out effective drugs against the virus. Chloroquine phosphate, an antimalarial drug is currently used for the treatment. Studies on the harmful effects of chloroquine is in progress. India is rich in traditional medical practicing such as Ayurveda, Siddha, Unani etc. Ministry of AYUSH is trying to implement an interdisciplinary treatment encompassing all traditional methodologies. It is proven that Ashwagandha rasayana (Withania sominefera L.Dunal) has better functions than hydroxychloroquine. The ayurvedic formulations such as Sudarshan Ghanvati and Sanshamanivati are also used. The combination of hydroxychloroquine (HCQ) and azithromycin is found to cure COVID-19 more effectively. Use of Tocilizumab is found to cure the respiratory disorders associated with COVID. Favilavir turns out to be yet another effective drug. The alternative medical system has effective prophylaxis and is considered better for the treatment of COVID-19. Ayurveda and yoga improve immunity thus maintaining good health. This review throws light on the mode of progression of the virus along with the various treatment protocols adopted to fight COVID-19.

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2021

Journal Article

A. S. Kumar, Leema, M., SriDevi, S., Sreesaila, S., Anil, L. J., Mohit, M., Krishnan, H., and Dr. Zeena S. Pillai, “A review on synthesis and various pharmacological aspects of Rhinacanthin-C with special emphasis on antidiabetic activity”, Materials Today: Proceedings, 2021.[Abstract]

Rhinacanthus nasutus is a plant widely distributed in Southeast Asia. It finds application as folk medicine and is used to cure a variety of diseases. Rhinacanthin-C (3-(3- hydroxyl-1,4-dioxo 1,4-dihydronaphthalen-2-yl)-2,2-dimethylpropyl (2E,6E)-2,6-dimethylocta-2,6-dienoate) is one of the major bioactive naphthoquinone ester isolated from the plant extract. This compound is reported to have anti-inflammatory, anti-proliferative, analgesic, anti-allergic, anti-fungal, anti-diabetic and neuroprotective properties. Reports have shown that it is used for diabetic nephropathy as well. It is reported to be noncarcinogenic, nontoxic and non-mutagenic. This review sheds light on the extraction, synthesis and pharmacological properties of Rhinacanthin-C.

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2021

Journal Article

A Santhy, Saraswathyamma, B., A. Krishnan, P., and Luscious, L., “Nanomaterials incorporated electrochemical sensors for the monitoring of pyridoxine: A mini review”, Materials Today: Proceedings, 2021.[Abstract]

<p>Pyridoxine (PY) or vitamin B6 is one of the water-soluble B vitamins which plays a crucial role in the functioning of the nervous system. Vitamin B6 is highly requisite to sustain healthy skin and immune system in the human body. Moreover, PY is extremely important in the activities of several enzymes that take part in the metabolism of amino acids, proteins, etc. The insufficiency of PY will result in anemic conditions and may lead to perpetual damages in the brain. Also, recent studies revealed that enough Vitamin B6 in the human body can reduce the severity of the illness like diabetes, stress, etc. in patients with Covid-19 infections. Hence the analytical detection of PY from real samples is vital to monitor the level of this vitamin in biological fluids and to control the quality of the pharmaceutical dosages. Numerous analytical methods came out for the detection of PY from biological and pharmaceutical samples so far. However electrochemical approaches hold some discernible advantages like simplicity, amenability for miniaturization, fast response time, etc. from other analytical techniques. The objective of this review is to exemplify the importance of electrochemical methods for the detection of biomolecules especially vitamin B6. Several electrochemical sensors were fabricated for biomolecules based on nanomaterials, as these are an excellent class of materials to modify the electrodes due to their unique properties. Thus, the review emphasizes the strategies adopted for the electrochemical detection of PY, specifically based on nanomaterials.</p>

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2021

Journal Article

A Santhy, Saraswathyamma, B., Krishnan, R. G., and Gopakumar, G. M., “Electrochemical sensors as a versatile tool for the quantitative analysis of Vitamin B12”, Chemical Papers, 2021.[Abstract]

Vitamin B12 (Vit B12) is one of the essential vitamins which play a prominent contribution in the functioning of neurological systems and the production of blood cells. Vit B12 is found in very low concentrations of the picomolar level in blood serum. The deficiency and surplus concentrations of Vit B12 in the blood may cause serious health disorders. The main sources of Vit B12 are meat, egg, dairy products, etc., and therefore, vegetarians are highly susceptible to Vit B12 deficiency. The insufficiency of Vit B12 in blood serum can be treated by giving proper Vit B12 supplements. Thus, selective, and sensitive point-of-care devices for the monitoring of Vit B12 from biological, pharmaceutical, and food samples are highly essential. A lot of analytical techniques are in practice for the quantification of Vit B12. Nevertheless, electrochemical methods possessed some advantages over other techniques because of their simplicity, cost-effectiveness, and fast response time. Vit B12 is an electroactive compound and is widely exploited in electroanalytical studies. There have been several reports for the electrochemical detection of Vit B12 using carbon-based electrodes, metal electrodes, paper electrodes, screen printed electrodes (SPE), bismuth film electrodes (BFE), indium tin-oxide (ITO) electrodes, dropping mercury electrodes (DME), etc., and to our knowledge, the picomolar level detection of Vit B12 was achieved only via ITO electrode. This review brings an exhaustive study of the electrochemical sensors and their analytical characteristics for Vit B12 for the first time by considering the advantages of the electrochemical techniques over other analytical methods. We have also compared the advantages and disadvantages of the existing electrochemical sensors for Vit B12. The review aims to explore the area of electrochemical sensing in the analysis of Vit B12 for further research by overcoming all challenges in the future.

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2021

Journal Article

Dr. Naveen V. Kulkarni, “International conference on advances in material science and chemistry (ICAMSC – 2020): Editorial”, Materials Today: Proceedings, 2021.

2021

Journal Article

A. S. Sethulekshmi, Jayan, J. S., Dr. Saritha A., and Kuruvilla Joseph, “MoS2: Advanced nanofiller for reinforcing polymer matrix”, Physica E: Low-dimensional Systems and Nanostructures, vol. 132, p. 114716, 2021.[Abstract]

The discovery of graphene, a well-known two dimensional material (2D) and its subsequent utility has extended the significance of other 2D materials. Molybdenum disulﬁde (MoS2), an important member of transition metal dichalcogenides (TMD) is having a structure analoguos to graphene. The excellent electronic, optical, thermal and mechanical properties of MoS2 makes it a remarkable material in almost all these areas. Currently, MoS2 based polymer nanocomposites have been gaining research interest owing to the outstanding reinforcement ability of nanosized MoS2. In this review, we intend to cast light on the various synthesis and functionalization methods of MoS2 nanosheets. We have also consolidated the various polymer/MoS2 nanocomposites, their applications and future proepectives in a comprehensive way.

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2020

Journal Article

R. G. Krishnan, Rejithamol, R., and Dr. Beena S., “Non-enzymatic electrochemical sensor for the simultaneous determination of adenosine, adenine and uric acid in whole blood and urine”, Microchemical Journal, vol. 155, p. 104745, 2020.[Abstract]

Herein we report for the first time, a simultaneous voltammetric sensor for adenosine, adenine and uric acid using a pencil graphite (PG) substrate electropolymerised with 2-amino-5-mercapto-1,3,4-thiadiazole in phosphate buffer with pH 7. The developed sensor was characterized morphologically, structurally and electrochemically. Under the optimum conditions, a linear concentration range of 0.2–25.6 µM, 0.05–12.8 µM and 5–1200 µM was obtained with a detection limit of 0.19 µM, 0.039 µM and 2.74 µM for adenosine, adenine and uric acid respectively.  Viability of the sensor was also tested in blood and urine samples, and it was found that the sensor is an excellent tool for the simultaneous determination of the above mentioned targets.

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2020

Journal Article

R. Rejithamol and Dr. Beena S., “Electrochemical quantification of pyridoxine (VB6) in human blood from other water-soluble vitamins”, Chemical Papers, vol. 74, no. 6, pp. 2011 - 2020, 2020.[Abstract]

For the first time reporting a pencil graphite electrode modified with gold nanoparticles and non-conducting polymeric film of o-aminophenol for the selective determination of pyridoxine (VB6) from other water-soluble vitamins in human blood. The fabricated electrode was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, electrochemical impedance spectroscopy, and attenuated total reflection infrared spectroscopy. Voltammetric response of VB6 on the fabricated electrode was investigated out using cyclic and differential pulse voltammetric techniques. Under optimized conditions, an irreversible oxidation peak at + 0.632 V was observed which corresponds to the oxidation of VB6. The oxidation peak current and the pyridoxine concentration were found to be linear in the range from 5 to 200 μM with a detection limit of 0.30 μM. The sensitivity of the proposed electrode was calculated to be 3.373 μA/μM/cm2 with excelled reproducibility and stability. The electrode is suitable for the routine analysis of VB6 in human blood samples as it highly selective from other water-soluble vitamins.

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2020

Journal Article

Athira Krishnan, Dr. Beena S., and S.M.A. Shibli, “A novel high performance Ti/Ti–W- reinforced polyaniline functionalized Ni–P electrode for high sensitive detection of dopamine from urine sample”, Materials Chemistry and Physics, vol. 244, p. 122680, 2020.[Abstract]

We, in our previous work, detailed the new design technology for the synthesis of novel TiO2/TiO2-WO3 core/shell composite (Ti/Ti–W) via the application of titanium turnings. Herein, we exploited the strategy with appropriate alternations to broaden the industrial significance of the method as well as the material. The work embodies a polyaniline assisted modification of Ti/Ti–W (0.1 g Ti metal/1:2 Ti–W) to develop a novel hybrid composite that has not yet been synthesized and studied. The composite was used to fabricate a sensing electrode for dopamine detection by electroless deposition from Ni–P bath. Cyclic voltammetric results revealed the sensing performance of Ni–P/PANI/Ti/Ti–W electrode towards dopamine detection. Further, differential pulse voltammetry (DPV) was employed to detect the sensing potential and sensing current, and the detection limit was found to be as low as 0.0037 μM with a sensitivity of 44.7 μA/μM cm2. The linear range of the optimized sensing electrode was 0.1–50 μM. Moreover, the electrode offered a remarkable detection of dopamine even in presence of other electroactive species such as AA, UA, NaCl and glucose. The real sample analysis explored Ni–P/PANI/Ti/Ti–W as a potential sensing electrode and can detect dopamine from urine sample with high sensitivity and accuracy. The obtained electroanalysis results confirm a 2H+/2e− mechanism of sensing in the developed electrode.

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2020

Journal Article

R. G. Krishnan, Dr. Beena S., RajT., A., and Gopika, M. G., “Poly (riboflavin) modified pencil graphite for the simultaneous electrochemical determination of serotonin and dopamine”, AIP Conference Proceedings, vol. 2259, p. 020007, 2020.[Abstract]

A poly (riboflavin) modified pencil graphite electrode was fabricated by electropolymerization process. The fabricated electrode was characterized morphologically and electrochemically. Dopamine and serotonin was found to undergo irreversible electroxidation at potentials 0.103 V and 0.292 V respectively on the modified electrode surface in phosphate buffer saline pH 7.4. Also the potential of the developed electrode as a tool to determine the concentrations of serotonin and dopamine was also described. The sensor possesses a linear range of 1 µM – 320 µM. The efficiency of the sensor to be used in practical samples was tested using human serum samples.

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2020

Journal Article

R. G. Krishnan, Dr. Beena S., Dr. Sreedhar K. M., David, S., Prakash, A. P., and Greeshma, S., “Mixed metal oxide based electrochemical sensing of inhibitory neurotransmitter serotonin in the presence of dopamine”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012105, 2020.[Abstract]

A mixed metal oxide modified electrode has been employed for the voltammetric determination of neurotransmitter serotonin in the presence of dopamine. The electrode was morphologically and electrochemically characterized using scanning electron microscope and cyclic voltammetry respectively. Differential pulse voltammetry were performed to measure the serotonin concentration at the electrode surface. A dynamic linear range of 0.2-52 μm was obtained. Viability of the sensor was tested in blood sample.

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2020

Journal Article

A Santhy, Dr. Beena S., G Rajasree, K., and Greeshma, S., “A commercially viable electrochemical sensor for the immunosuppressant drug mycophenolate mofetil utilizing pencil graphite electrode”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012127, 2020.[Abstract]

An electrochemical sensor facilitating the electro oxidation of the immunosuppressant, mycophenolate mofetil (MMF) on pencil graphite electrode (PGE) has been developed. The electrochemical characteristics of the electrode was evaluated by virtue of cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The PGE was characterized by XRD analysis and FE-SEM before and after the electrooxidation of MMF at the electrode. CV of MMF exhibited two irreversible oxidation peaks at about 0.66 V and 0.84 V. In the DPV studies, two linear ranges were observed towards the determination of MMF concentration from 20 nM – 300nM and 300 - 1000 nMin 0.1M phosphate buffer with pH 6. The limit of detection of the sensor was estimated to be 1.80nM. The proposed sensor exhibited acceptable selectivity for quantifying the MMF in pharmaceutical dosage forms and urine samples.

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2020

Journal Article

A Santhy, Dr. Beena S., Veena,, and Shahina, S., “Electrochemical quantification of vitamin B9 on poly tyrosine modified pencil graphite electrode”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012128, 2020.[Abstract]

An electrochemically polymerized tyrosine film on pencil graphite substrate was found to be an affordable electrochemical sensor for vitamin B9 or folic acid. The electrochemical characteristics of the electrode was studied using cyclic and differential pulse voltammetric techniques in phosphate buffer (pH 7). The surface study of the electrode was carried out by scanning electron microscopy. The sensor showed a linear range from 1μM – 85 μM concentration range by means of differential pulse voltammetry. A good repeatability was obtained for the developed sensor and was utilized for the sustainable application in pharmaceutical tablets.

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2020

Journal Article

A Santhy, Dr. Beena S., Namboothiri, U. S. Krishnan, Anupriya, S., and Sreeranjini, C. V., “A pencil graphite electrode modified with poly nicotinamide as a framework for the electrochemical detection of propranolol hydrochloride”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012125, 2020.[Abstract]

Herein, a novel polymer film modified pencil graphite electrode as an electrochemical sensor for the propranolol hydrochloride (PROP) is reported. A poly nicotinamide modified pencil graphite (Poly-NA-PGE) electrode was used for the electrochemical detection of propranolol hydrochloride using differential pulse voltammetry. The modified electrode was characterized by Scanning Electron Microscopy. Furthermore, the experimental parameters like pH of the supporting electrolyte, concentration of the nicotinamide and polymerisation cycles were optimized. The cyclic voltammetry of propranolol hydrochloride showcased an irreversible oxidation peak at 0.9361V. The sensor showed a linear range from 1μM - 20μM with a correlation co-efficient of 0.99825. The repeatability of the electrode was excellent with an RSD of 3.5%. The sensor was utilized effectually for the determination of propranolol from the commercially available pharmaceutical tablet.

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2020

Journal Article

R. Rejithamol, Dr. Beena S., Krishnan, M., Dharan, M. T., and Anusree, L., “One pot synthesis of amino-ethanethiol derivatives of aromatic aldehydes by the catalytic action of DBU”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012121, 2020.[Abstract]

A facile and effective one pot organic synthesis of benzylidene amino-ethanethiols from the condensation reaction between 2-aminoethanethiol and aromatic aldehydes by the catalytic action of 1, 8-diazabicyclo [5.4.0] undec-7-ene (DBU) at mild reaction conditions. For the best our knowledge there is no report on the organic synthesis of benzylidineamino-ethanethiols

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2020

Journal Article

S. P. S., Jayan, J. S., Dr. Saritha A., V. Babu, S., and G., S., “Synthesis and Performance Evaluation of BaxSr1 – xTiO3 Ceramic-Based MIM Capacitor for Energy Storage Application”, Integrated Ferroelectrics, vol. 212, pp. 177-189, 2020.[Abstract]

AbstractMetal-insulator-metal (MIM) capacitor with high-k insulator such as BST enhances specific capacitance. The effects of barium mole fraction (x) of BaxSr1 – xTiO3 ceramic-based MIM capacitor on specific capacitance and leakage current density are reported in this article. BaxSr1 – xTiO3 nanopowder for various x are synthesized using solid-state reaction method and the performance parameters of Ag/BaxSr1 – xTiO3/Ag MIM capacitors are evaluated. The mean crystallite sizes are in 20 to 60 nm range. Ba0.7Sr0.3 TiO3 ceramics show higher relative permittivity owing to its higher mean crystallite size. The insulator with higher crystallite size at dominant orientation shows enhanced leakage performance. Ba0.1 Sr0.9 TiO3 ceramic capacitor shows optimum performance altogether.

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2020

Journal Article

J. A, Jitha S Jayan, Dr. Saritha A., A.S., S., and Gopika Venu, “Superhydrophobic graphene-based materials with self-cleaning and anticorrosion performance: An appraisal of neoteric advancement and future perspectives”, Colloids and Surfaces A: Physicochemical and Engineering Aspects, vol. 606, p. 125395, 2020.[Abstract]

Lotus like materials having superhydrophobicity is attaining greater demand due to the possibility of molding them into different high end applications. The major issue related to self-cleaning superhydrophobic surfaces is their restricted mechanical properties. The development of nanotechnology has brought many advantages in the fabrication and properties of superhydrophobic surfaces and thus it enhanced the demand of superhydrophobic surfaces. Many scientific groups have studied and reported about the superhydrophobicity exhibited by graphene and its analogous derivatives. The fabrication of the devices having properties ranging from anti-sticking and self-cleaning to anti-corrosion and low friction is made possible by the incorporation of this wonderful two-dimensional material. This review focuses on the preparation and properties of graphene based superhydrophobic coating materials with special mention to the wide range of applications rendered by them.

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2020

Journal Article

J. S. Jayan, Dr. Saritha A., Deeraj, B. D. S., and Joseph, K., “Synthesis of self-assembled and porous nano titania-graphene oxide hybrids for toughening the epoxy”, Polymer Composites, vol. 41, pp. 4093-4103, 2020.[Abstract]

Abstract Nano titania (nTiO2) aggregated graphene oxide (GO) hybrid nanostructures were successfully prepared by employing 3-(Aminopropyl) triethoxysilane (APTES)-modified nTiO2 as precursor material. The resulting self-assembled core-shell hybrid structure was observed to have hierarchical porous structure with nTiO2 forming the core and GO forming the shell in accordance with transmission electron micrographs. The mechanical properties of the hybrid composites were compared with that of individual GO and nTiO2 loaded systems and improved performance was observed. The incorporation of the hybrid filler improved the fracture toughness of epoxy composites by about 200%, which is indeed significant. Hence, this novel approach of employing self-assembled APTES modified nTiO2 agglomerated GO hybrids as filler in epoxy was found to be beneficial in enhancing the toughness of epoxy.

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2020

Journal Article

Jitha S Jayan, Dr. Saritha A., Deeraj, B. D. S., and Kuruvilla Joseph, “Triblock copolymer grafted Graphene oxide as nanofiller for toughening of epoxy resin”, Materials Chemistry and Physics, vol. 248, p. 122930, 2020.[Abstract]

Inspired by the mechanical strength produced by Graphene oxide (GO) and Polyethylene Glycol-b-Polypropylene Glycol-b-Polyethylene Glycol (TBCP) block copolymer separately in epoxy composites, we have incorporated both these materials in the form of a graft (GO-g-TBCP) in epoxy. This idea of exploiting the synergistic effect of nanofiller and block copolymer in the form of a graft in the epoxy matrix is a maiden attempt. The grafting process was confirmed through FTIR, FTNMR, XPS, XRD and Raman spectroscopy. Both GO-g-TBCP and GO were incorporated into epoxy and the mechanical properties of the composites were analysed. The fracture toughness showed a tremendous improvement of about 400% without affecting the inherent tensile properties. GO-g-TBCP toughened epoxy displayed about 100% improvement in storage modulus and 33% improvement in tensile strength. These enhanced properties were explained by probing into the sequential arrangement of the nanostructures into a fractal-like structure with the help of HRTEM and SEM micrographs.

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2020

Journal Article

J. S. Jayan, Deeraj, B. D. S., Dr. Saritha A., and Kuruvilla Joseph, “Theoretical modelling of kinetics of glass transition temperature of PEG toughened epoxy”, Plastics, Rubber and Composites, vol. 49, pp. 237-244, 2020.[Abstract]

ABSTRACT In this paper, we examined glass transition, a very important parameter that determines the properties and applications of epoxy resins by the innovative approach of kinetic study. The effect of thermoplastic filler Polyethylene Glycol-1000 (PEG-1000) on the kinetics of glass transition temperature of epoxy was analysed by varying the filler loadings and the heating rates. The differential scanning calorimetry curves were plotted at heating rates of 5, 10, 15 and 20°C, respectively and the kinetics of glass transition by varying the heat rates was investigated. Kissinger and Moynihan methods were employed to analyse the glass transition kinetics. The changes in glass transition have been interpreted remarkably with the constrained polymer region of the systems. The improvement in toughness of about ≈ 213% was obtained compared to the neat epoxy with an addition of about 1 wt-% of PEG loading. The toughening mechanisms were elucidated by analysing the scanning electron microscopic images of fractured samples.

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2020

Journal Article

B. D. S. Deeraj, R., H., Jayan, J. S., Dr. Saritha A., and Kuruvilla Joseph, “Enhanced visco-elastic and rheological behavior of epoxy composites reinforced with polyimide nanofiber”, Nano-Structures & Nano-Objects, vol. 21, p. 100421, 2020.[Abstract]

High performance epoxy composites are now a days a must in several industrial applications. In the present work electrospun polyimide (PI) nanofibers with excellent thermal and mechanical properties was used as a reinforcement in epoxy matrix via a simple mechanical mixing followed by thermal curing method. Well defined electrospun nanofibers of aromatic polyimide (PI) were successfully prepared from electrospinning Poly (amic acid) (PAA) and subsequent thermal treatment. The fiber morphology was analyzed using Transmission electron microscopy (TEM) and Atomic force microscopy (AFM). PI/epoxy nanocomposites with different PI loadings were prepared using chopped PI mats. The dynamic mechanical performance of these PI/epoxy composites was investigated to determine the influence of PI fibers in reinforcing the epoxy matrix. The fracture toughness of these composites displayed a note worthy improvement of 20 % at 1 w% loaded samples and the surface of the fractured samples was investigated by Scanning electron microscope. The rheological properties of these systems show a tremendous increase in the storage and loss modulus when compared to neat systems. In addition flow models were employed to model the rheological data and the comparison was made with the experimental data.

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2020

Journal Article

J. S. Jayan, Dr. Saritha A., Deeraj, B. Durga Siva, and Joseph, K., “Graphene Oxide as a Prospective Graft in Polyethylene Glycol for Enhancing the Toughness of Epoxy Nanocomposites”, Polymer Engineering & Science, vol. 60, pp. 773-781, 2020.[Abstract]

Polyethylene glycol (PEG) was successfully grafted onto the surface of graphene oxide (GO) by the “grafting to” technique. PEG, GO as well as the PEG grafted GO (GO-g-PEG) was successfully incorporated into an epoxy matrix and subsequently cured using diethylenetoluenediamine (DETDA) to make epoxy nanocomposites. Mechanical, thermal, and rheological properties of the epoxy nanocomposites were studied to check the effectiveness of these fillers in the epoxy matrix. An improvement of 255% and 334% at a very low filler loading of about 0.1 wt% was observed in the fracture toughness of GO and GO-g-PEG loaded systems versus the neat epoxy. Toughening mechanisms are also explained by analyzing SEM images of the fractured surface. Modeling of rheological properties was carried out by following time-independent Newtonian model. The homogeneity of the epoxy filler systems are explained with the help of Cole–Cole plots. The thermal stability of the filler loaded epoxy composites was examined in detail by TGA. Improvements in mechanical properties reveal the potential benefit of the grafting process in epoxy toughening. POLYM. ENG. SCI., 60:773–781, 2020. © 2020 Society of Plastics Engineers

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2020

Journal Article

S. John, Kavya, G., Aparna, M. M., R Krishnan, A., Parvathy, R., Sreenath, T. S., and Akhil Sivan, “Organic base catalysed synthesis of benzimidazole”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012142, 2020.[Abstract]

A mild and effective protocol for benzimidazolesynthesis from o-phenylenediamine and aromatic aldehydes catalysed by DBU is described. The synthesized compounds find application in the pharmaceutical, dye and material science fields. Mild reaction conditions, low amount of chemicals and use of metal-free catalysts are the highlights of the reaction.

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2020

Journal Article

K. Sivaselvi and Dr. Gopal K., “Study to enhance the mechanical properties of natural rubber by using the carbon black (N550)”, Materials Today: Proceedings, vol. 26, pp. 378-381, 2020.[Abstract]

Natural rubber is one of the important material in the manufacturing industry with applications varying from footwear to an aircraft industries. An investigation was conducted on the nature of material so as to increase its effectiveness in its function in cleaning off water, dust and other impediments of the windscreen of automobiles. A research has been conducted on various compositions of rubber by adding various fillers to improve the properties. The main objective of this work is to enhance the mechanical properties of the natural rubber used in the windshield wiper blade using Carbon black (N550) in two different compositions. Abrasion test, hardness test, tensile and tear tests were conducted on the specimen.

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2020

Journal Article

S. Hema, Sreedha Sambhudevan, Mahitha, P. M., K Sultan, R., Raj, M., Anjana, A., Parvathy, S. U., Mahalekshmi, M. S., and Shankar, B., “Synthesis and characterization of doped nickel ferrite filled natural rubber nano composites”, IOP Conference Series: Materials Science and Engineering, vol. 872, p. 012179, 2020.[Abstract]

Synthesis of rubber nanocomposite containing differently doped ferrites were fabricated using Co-precipitation method. The nano particles characterization was carried out by SEM, FTIR and XRD to confirm that the ferrites were synthesized in nanometer dimensions. The rubber mixes were incorporated with metallic nano fillers and the obtained nanocomposites were analysed for mechanical studies such as hardness, specific gravity, tear and tensile strength. The copper doped samples shows excellent mechanical properties over other dopants and hence paving the way for decisive technical applications.

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2020

Journal Article

S. Hema, Sreedha Sambhudevan, Mahitha, P. M., Sneha, K., Advaith, P. S., K. Sultan, R., Sajith, M., Jose, B., Menon, S. K., and Balakrishnan Shankar, “Effect of conducting fillers in natural rubber nanocomposites as effective EMI shielding materials”, Materials Today: Proceedings, vol. 25, pp. 274-277, 2020.[Abstract]

An economical and effortless method for the production of flexible shielding material for feasible application has gained remarkable attention since the massive spread of technologies has notably marked up the electromagnetic pollution, which will cause interference or malfunctioning of electronic devices. Traditionally Electromagnetic Interference (EMI) shielding is achieved by using a metal screen to absorb it. But metals have low impact resistance, high density and are susceptible to corrosion, polymer nanocomposites with magnetic nanofillers become a radical alternative to this. Rubber based nanocomposites have considerable importance since they bear excellent multifunctional applications. The conductive fillers incorporated in the polymer matrix give out the advance functions like light weight, corrosion resistance and tailored coefficient of thermal expansion and ease of processing. In the class of magnetic materials that possess broad applications in technology, Polyaniline (PAni) gain much attention and cannot be replaced by any other magnetic material because they are less expensive, stable and widely used in high-frequency applications. Ferrites, belonging to ferromagnetic material which cannot be easily replaced by any other material as they are economic for a wide range of applications and ease of fabrication into complex shapes. Thus the use of hybrid fillers based on various combinations will be a possible solution for improved shielding effectiveness as well as the mechanical properties of nanocomposites.

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2020

Journal Article

P. M. Mahitha, Sneha, K., Advaith, P. S., K. Sultan, R., Sajith, M., Jose, B., Hema, S., Sreedha Sambhudevan, and Balakrishnan Shankar, “Conducting polyaniline based rubber nanocomposites – Synthesis and characterization studies”, Materials Today: Proceedings, vol. 33, pp. 1429-1433, 2020.[Abstract]

Dielectric polymer nanocomposites are extensively used in electronics and power systems due to their high breakdown strength, resilience and their capability to adapt any desired shape, moreover conducting flexible nanocomposites based on rubber is a promising material for electromagnetic wave shielding and dielectric materials. The prime objective of the study was to synthesize polyaniline (PAni) in a modest and cost-effective way, its characterization and composite preparation based on this synthesized PAni. The prepared PAni was characterized using Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and X Ray Diffraction (XRD) to authorize the formation and particle magnitude. PAni was inserted into natural rubber matrix using conventional method of mixing at different proportions. The selection of natural rubber as matrix was mainly due to its superior flexibility, resilience and elasticity. Conductivity increases fivefold upon the addition of 20% PAni to rubber matrix. The dielectric properties were studied at the desired frequency range. Dielectric studies show that permittivity as well as tan delta values increases with filler loading.

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2020

Journal Article

R. Rejithamol, Krishnan, R. G., and Dr. Beena S., “Electrochemical Quantification of L-tryptophan Via Molecular Imprinted Pyromellitic Acid Polymer-Based Indium Tin Oxide Electrode”, Journal of The Electrochemical Society, vol. 167, p. 117507, 2020.[Abstract]

Herein highlighting a molecular imprinted pyromellitic acid modified indium tin oxide electrode for the quantification of L-tryptophan. The quality and features of the modified electrode were in accordance with the basic characteristic features of a sensor in all perspectives. The morphological and the functional group identification of the electrode surface were done by scanning electron microscopy and infrared spectroscopy. The proposed electrode material exhibits prolonged stability with ease of handling for real sample analysis. The linear range of the fabricated electrode was noticed to be the highest linearity reported through a molecular imprinted electrode for the electrochemical quantification of L-tryptophan. The electrode has a linear range from 0.4 μM to 500 μM with lower detection limit of 0.1 μM. The sensitivity of the electrode was calculated to be 0.297 μM/μA/cm2.

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2020

Journal Article

G. S. Gopika, Raj, M. P. Pranav, Eapen, M., Rani, P., Lekshmipriya, S., Dev, A. P., and Dr. Zeena S. Pillai, “Hemicyanines-potential heavy metal ion sensors”, IOP Conference Series: Materials Science and Engineering, vol. 872, 2020.[Abstract]

The synthesis of four hemicyanine dyes are reported. Varying the donor-acceptor properties of hemicyanine dyes has a drastic influence on the aggregation properties and photophysical properties. 4-(N, N-dimethyl)amino benzaldehyde, 4-nitro benzaldehyde and 4-hydroxy benzaldehyde are used as donors. Quarternary salts of 2-methyl benzothiazole with bromoacetic acid and methyl iodide are used as acceptors. Synthesis and characterization of the dyes were carried out. Preliminary studies shows that these compounds possess pH sensing as well as heavy metal ion sensing properties.

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2020

Journal Article

C. Vincent, M.D, K., Jayan, J. S., and Dr. Saritha A., “Determination of drug loading efficiency of nano capsules formed by the O/W emulsification of block copolymer”, Materials Today: Proceedings, vol. 26, pp. 720-723, 2020.[Abstract]

The self-assembly nature of pluronic triblock copolymers have been exploited by materials scientists in the field of drug delivery. We have used Pluronic P123 block copolymer to load an antibiotic drug Amoxicillin and have analyzed the drug loading efficiency. The amphiphilic nature and micellization of Pluronic P123block copolymer was efficiently utilized and the morphology of drug loaded block copolymer is analyzed in detail and correlated with the loading efficiency. Moreover this study also focuses on the antimicrobial activities of the amoxicillin loaded Pluronic P123block copolymer. It is seen that the micelle serve as excellent payloads for the delivery of the most common drug amoxicillin.

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2020

Journal Article

A. Mary Alex, Kiran, M. D., Hari, G., Krishnan, A., Jitha S Jayan, and Dr. Saritha A., “Carbon dots: A green synthesis from Lawsonia inermis leaves”, Materials Today: Proceedings, vol. 26, pp. 716-719, 2020.[Abstract]

Carbon dots are class of carbon based zero dimensional materials having immense biological, chemical and physical properties due to their tuneable fluorescence and attractive physicochemical properties. Blue fluorescence emitting carbon dots were synthesized by following a green route from the carbonized Lawsonia leaves. The green synthesized carbon dots were characterized using UV visible and luminescent spectroscopy and the surface morphology was monitored using High resolution transmission electron microscopy. The carbon dots were doped with Fe2+ and the effect of doping on the fluorescence emission was also analysed.

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2020

Journal Article

N. Dileepkumar, Ganesh, S., Gopinathan, S., Jayan, J. S., Dr. Saritha A., Prasad, G., and Babu, J. S., “Green synthesis of graphene sand composites for the removal of hazardous chemicals from water”, AIP Conference Proceedings, vol. 2283, p. 020017, 2020.[Abstract]

Contamination of water bodies due to uncontrolled discharge of industrial waste dumping of municipal and household trash is one among the critical environmental quandaries faced today. This leads to the eutrophication of water bodies due to a higher concentration of elements such as phosphates and nitrates. As a potential answer to this quandary, this work tried to examine the impact of adding nano-sized coating of graphene on coastal black sand in the adsorption of heavy metals. In the current research, batch adsorption methods are employed to achieve Chromium adsorption (c-Adsorption) on nanocomposite and rich black coastal sand. The experiment is carried out with the anticipation of identifying the basic characteristics of clay soils, the effect of adsorption of chromium in soil in nanoscale coating and the dependence on concentration, pH values and contact time.
REFERENCES

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2019

Journal Article

Athira Krishnan, Bency Joseph, Krishna M Bhaskar, Suma M S, and S. M. A. Shibli, “Unfolding the Anticorrosive Characteristics of TiO2–WO3 Mixed Oxidere-inforced Polyaniline Composite Coated Mild Steel in Alkaline Environment”, Polymer Composites, pp. 2400-2409, 2019.[Abstract]

Electrically conducting polymer incorporated coatings effectively replaced chromate coatings, once widely employed for corrosion deterrence but now strictly restricted due to the environmental hazards. Here polyaniline nanocomposite was prepared by in situ polymerization of aniline monomer in presence of TiO2–WO3 powder, blended with PVC matrix and coated over mild steel specimens to evaluate its anti‐corrosion property in alkaline environment. Structural parameters of the composites and coatings were obtained from XRD and SEM‐EDS studies. Electrochemical parameters that govern the inhibitive efficiency of pigmented steel coupons were explored by Tafel polarization, electrochemical impedance spectroscopy, and open circuit potential measurements. The addition of (0.1 g) 1:1 TiO2–WO3 to PANI (polyaniline) improve the protective efficiency of PANI from 65% to 97.5%. PANI/TiO2–WO3 loaded specimen surface attained a state of passivity through uniform distribution of composite and characterized by the hydrophobic behavior that make it resistive to corrosive environment. Polarization studies identified the composite incorporated PANI as a mixed inhibitor. In order to extend the synthetic utility of prepared pigment, coated specimens are evaluated for their anticorrosive activity in acidic and mixed bacterial culture medium. The present work also included a detailed mechanism of passivation in view of the results of corrosion studies together with available literature studies. POLYM. COMPOS., 40:2400–2409, 2019. © 2018 Society of Plastics Engineers

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2019

Journal Article

M. Kunjappan Aswathi, Prof. M. Padmanabhan, Mathew, L., Saha, P., Terzano, R., Kalarikkal, N., Volova, T., and Thomas, S., “Carbon nanotube reinforced poly(trimethylene terephthalate) nanocomposites: Viscoelastic properties and chain confinement”, Polymer Engineering & Science, vol. 59, pp. E435-E445, 2019.[Abstract]

Through a very facile route, a new class of nanocomposites involving poly(trimethylene terephthalate; PTT) and multiwalled carbon nanotubes (MWCNTs) was developed which was found to be high performance engineering material showing high modulus. Morphological, mechanical, viscoelastic, and thermal properties of the PTT nanocomposites with varying compositions of MWCNT were systematically studied and the results were analyzed. The dynamic mechanical and tensile properties of all the nanocomposites were seen to be enhanced with the addition of MWCNT and the sample containing 2 wt% MWCNT showing a storage modulus as much as 9.4 × 108 GPa. The results were correlated with the morphological features obtained from scanning electron microscopy and transmission electron microscopy. Coefficient of effectiveness, degree of entanglement density, and reinforcement efficiency factor were estimated from the storage modulus values and, in addition, the degree of chain confinement also could be quantified. Furthermore, theoretical modelling was also done on the elastic properties of the composites. The crystallization temperature, glass transition temperature, and percentage crystallinity were estimated for all the nanocomposites and it was found that the sample with 3 wt% MWCNT content exhibited the highest glass transition temperature of 68.2°C. POLYM. ENG. SCI., 59:E435–E445, 2019. © 2018 Society of Plastics Engineers

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2019

Journal Article

P. K. Sandhya, M.S. Sreekala, Prof. M. Padmanabhan, Jesitha, K., and Sabu Thomas, “Effect of starch reduced graphene oxide on thermal and mechanical properties of phenol formaldehyde resin nanocomposites”, Composites Part B: Engineering, vol. 167, pp. 83 - 92, 2019.[Abstract]

Phenol formaldehyde (PF) resins are one of the oldest synthesized and very widely used resins. Their properties can be improved with the incorporation nano-fillers even with lower loadings. Graphene materials have attracted significant attention in recent years owing to its exceptional thermal, mechanical and electrical properties. Herein, we report a very simple and effective way to reduce graphene oxide (GO) by using highly abundant potato starch instead of conventionally used toxic and hazardous reducing agents like hydrazine. The reduced GO (RGO) is then effectively incorporated into PF resin by optimizing various processing parameters. The reinforcing effect of RGO sheets on the PF matrix was investigated by X-ray diffraction (XRD) and Transmission Electron Microscopy (TEM). The effect of RGO on thermal properties of the polymer nanocomposites was studied using Thermogravimetric Analysis (TGA). The mechanical properties of PF/RGO composites were studied by tensile and Izod impact tests. The fracture mechanism of the composites was investigated by Scanning Electron Microscopy. Theoretical prediction of the mechanical properties of the nanocomposites using Halpin-Tsai models gave sufficient information regarding the orientation of graphene sheets in PF matrix.

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2019

Journal Article

R. G. Krishnan, Greeshma, S., D. Morris, S., Rameshan, S. S., and Dr. Beena S., “Morphological Studies of Disposable Graphite and its Effective utilization for Vitamin B12 Analysis in Pharmaceutical Formulations”, Materials Today: Proceedings, vol. 18, Part 7, pp. 3314 - 3320, 2019.[Abstract]

Electrochemical sensor for the determination of Vitamin B 12 was fabricated using a disposable pencil graphite electrode. The main highlight of this work is that without any electrode modification and analyte pre-concentration, direct electrochemical detection of Vitamin B 12 was made possible. Morphological and structural studies were incorporated. Electrochemical studies were done using cyclic voltammetry and differential pulse voltammetry. Electrochemical reduction of Vitamin B 12 was observed at -0.82 V. Sensor exhibited a linear range of 2.5-30 nM with a sensitivity of 1.96 µA/nM/cm2. The viability of the sensor towards practical use was tested in commercial Vitamin B 12 tablet.

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2019

Journal Article

R. Rejithamol, Dr. Beena S., Sajitha, C. S., Dileep, N. K. Malavika, Drisya, A., and Keerthi, P. R., “Synthesis and characterization of phenylacrylonitrile derivatives of aromatic aldehydes in presence of DBU”, IOP Conference Series: Materials Science and Engineering, vol. 561, p. 012017, 2019.[Abstract]

An efficient one pot synthesis of phenylacrylonitrile derivatives from the condensation of electronegative active methylene group of 2-nitrophenylacetonitrile with aromatic aldehydes using diazabicycloundecene(DBU) as anamidine base.

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2019

Journal Article

R. Rejithamol, R, K. P., and Dr. Beena S., “A novel disposable pencil graphite electrode for the voltammetric determination of cysteamine”, Materials Today: Proceedings, vol. 18, pp. 5081 - 5086, 2019.[Abstract]

A highly sensitive electrochemical sensor was fabricated using disposable pencile graphite electrode for the determination of cysteamine. Electrode characterization was done using scanning electron microscopy and X-Ray diffraction studies. The electrochemical properties of the PGE were studied using cyclic voltammetry and differential pulse voltammetric methods. The oxidation peak of cysteamine was observed at a potential of +0.446 V in 0.1 M NaOH and is attributed to the oxidation of the cysteamine to the dimer cystamine. The fabricated sensor exhibited a linear dynamic range of 10µM-110µM. The sensitivity was found to be 0.4077 µA/µM/cm2, with a detection limit of 4µM. The proposed electrochemical sensor was used for the determination of cysteamine in urine samples with high selectivity..

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2019

Journal Article

P. Ajith, Murali, A. S., Sreehari, H., Vinod, B. S., Anil, A., and Dr. Smitha Chandran S., “Green Synthesis of Silver Nanoparticles using Calotropis gigantea extract and its Applications in Antimicrobial and Larvicidal activity”, Materials Today: Proceedings, vol. 18, no. 7, pp. 4987 - 4991, 2019.[Abstract]

Green synthesis of nanoparticles has gained much attention among the scientific community because of its cost effectiveness, simplicity, reduced usage of chemicals and ecofriendly approach. Silver nanoparticles were synthesized using Calotropis gigantean leaf extract, commonly called as crown flower and were characterised using UV spectrophotometry. The Larvicidal potential of the synthesised particles were evaluated. Antimicrobial studies against gram positive and gram negative microorganisms were evaluated using standard methods and the results indicates good activity against both the strains of microorganism studied.

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2019

Journal Article

A. Omanakuttan, Priyanka, G., and Divya Mohan R, “Synthesis Characterisation and anti-microbial properties of two Salicylaldimine Schiff base complexes of transition metals”, IOP Conference Series: Materials Science and Engineering, vol. 561, p. 012050, 2019.[Abstract]

Schiff bases and their metal complexes are widely used in the area of pharmacology owing to their anti-microbial properties. In this article, we detail the synthesis of two metal complexes, viz. Cu(II) and Zn(II) complexes of a salicylaldimine Schiff base formed from orthophenylene diamine (o-phdn) and salicylaldehyde. The complexes 1 [Cu(sal-o-phdn)] and 2 [Zn(sal-o-phdn)] are characterized by spectroscopic techniques like Fourier Transform Infrared spectroscopy (FT IR) and UV-Visible spectroscopic studies. The biological activity of the two complexes along with the Schiff base resistant to two gram positive and two gram negative bacteria is measured by Disc diffusion method. The complexes are found to be good candidates against certain microorganisms.

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2019

Journal Article

B. D. S. Deeraj, Dr. Saritha A., and Kuruvilla Joseph, “Electrospun styrene-butadiene copolymer fibers as potential reinforcement in epoxy composites: Modeling of rheological and visco elastic data”, Composites Part B: Engineering, vol. 160, pp. 384-393, 2019.[Abstract]

In this work, nanofibers of poly (styrene-co-butadiene) copolymer were successfully fabricated using electrospinning technique. The optimum polymer concentration was found to be 18 wt % at an applied voltage potential of 10 KV. The morphology of the prepared fibers was observed by Polarized light microscope (PLS) and Transmission Electron Microscope (TEM). Short fiber reinforced composites were fabricated by incorporating these chopped electrospun fibers at different weight percentages into the epoxy matrix and subsequently the properties of these composites were analyzed. The morphology of the fractured epoxy surface was investigated by Scanning Electron Microscope (SEM) to observe the crack propagation through the system. The tensile strength of the composite samples showed an increasing trend with an 18% improvement at 2.5 wt % loading. The fracture toughness of the samples analyzed by single notch bend test exhibited a remarkable improvement with 104% enhancement at 2.5 wt % loading. The toughening mechanism was elucidated from the morphology obtained using SEM. The Dynamic storage modulus of the fiber reinforced samples at 5 wt % loading revealed an improvement of nearly 2 folds than that of neat epoxy samples and experimental results were compared with theoretic models. The thermal properties of samples were also examined and it was found that all the samples are thermally stable in a considerable range of temperature. Dynamic rheological studies were also employed to examine the impact of fiber loading on the viscosity and modulus of the epoxy matrix and a few flow models were interpreted with the experimental data obtained.

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2019

Journal Article

R. Konnola, Deeraj, B. D. S., Sampath, S., Dr. Saritha A., and Joseph, K., “Fabrication and Characterization of Toughened Nanocomposites Based on TiO2 Nanowire-Epoxy System”, Polymer Composites, vol. 40, pp. 2629-2638, 2019.[Abstract]

TiO2(B) nanowires (TiO2(B)-NWs) were synthesized and characterized by X-ray diffraction, and Scanning Electron Microscopy (SEM) micrographs and the influence of different morphologies of TiO2 nanostructures on the mechanical performance of epoxy nanocomposites were thoroughly investigated. Transmission Optical Micrograph images of TiO2(B)-NW/epoxy nanosuspension reveals an excellent dispersion of TiO2(B)-NWs in the epoxy matrix. Tensile strength ( 26%), tensile modulus ( 16%), and fracture toughness ( 136%) improved remarkably for TiO2(B)-NWs modified epoxy composites. The mechanism that paved way to the enhancement in the fracture toughness of the TiO2(B)-NW/epoxy nanocomposites was evaluated. SEM micrographs disclose that the phenomena of shear yielding, crack deflection and crack bridging are responsible for the improved fracture toughness of TiO2(B)-NW/epoxy composite. Moreover, the analysis of visco-elastic properties revealed a very high modulus and improved Tg for the TiO2(B)-NW/epoxy composites when compared with neat epoxy owing to better filler/matrix interfacial interaction between TiO2(B)-NWs and epoxy matrix. This was further confirmed by quantitative analysis of the constrained region and by the evaluation of the interaction parameter B. TGA study shows that the thermal stability of composites are not compromised by the incorporation of TiO2 nanofillers. The obtained results can be considered as beneficial in the manufacture of components with higher strength-to-weight ratios for such uses as windmill blades or aircraft components. POLYM. COMPOS., 40:2629–2638, 2019. © 2018 Society of Plastics Engineers

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2019

Journal Article

M. Leema, Sreekumar, G., Akhil Sivan, and Dr. Zeena S. Pillai, “Synthesis of silver nanoparticles from a bioactive precursor”, Materials Today: Proceedings, vol. 18, pp. 4724-4728, 2019.[Abstract]

Silver nanoparticles are well known for their medicinal properties from time immemorial. Improving their potential applications demands a greener approach to synthesise them. Embelin, a bioactive molecule belonging to the Myrsinaceae family has gained considerable research interest over the past few years due to its diverse properties as anti-inflammatory, antitumour, analgesic and antimicrobial agent. Being an antioxidant, embelin is capable of reducing metal to metal nanoparticles. In this report, reduction of silver to silver nanoparticles has been carried out using embelin. The silver nanoparticles thus formed were characterised using absorption spectroscopy as well as TEM measurement. The synergic effect on the activity of the silver-embelin system is compared with pure embelin

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2019

Journal Article

S. Adwaith, Suresh, A., Raman, A., Reji, K., G. Parvathy, Ananthakrishnan,, Adithyakrishnan,, Jitha S Jayan, and Dr. Saritha A., “Effective reuse of CIIR nanocomposite based CPC by the evaluation of thermal decontamination as well as gas barrier properties”, Materials Today: Proceedings, vol. 18, pp. 4630-4636, 2019.[Abstract]

Nanocomposite technology opens up a new era in the study of polymeric materials. Carbon nanotubes, due to their extremely high mechanical strength finds use as a filler material in many polymer matrices and can be viewed as one of the most promising area driven towards commercial applications. Nevertheless nanoclay is also equally good as filler in increasing the mechanical, barrier as well as thermal characteristics of chlorobutyl rubber (CIIR) matrix. The synergistic effect produced by nanoclay and carbon nanotube in enhancing the properties of chlorobutyl rubber enhances its efficacy towards the fabrication of industrially relevant materials. The nanocomposites were prepared using cloisite 30 B and carbon nanotubes separately and a hybrid nanocomposite was prepared by incorporating these two fillers to evaluate the synergistic effect of the fillers. The mechanical, dielectric, solvent diffusion and barrier properties of the nanocomposites were analyzed. The results show an enhancement in the aforementioned properties and reveal that both the carbon nanotubes and nanoclay contribute synergistically towards the enhancement in properties. Moreover the enhanced solvent resistance as well as gas barrier properties suggests the feasibility of the utilization of the material in the production of chemical protective clothing. Evaluation of thermal decontamination of the proposed CPC material reveals its potential for its effective reuse.

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2019

Journal Article

A. Raman, Ananthakrishnan, K. S., Adithyakrishnan, M. R., Geethu, S., Neeraja, J., Reji, K., Parvathy, G., Adwaith, S., Suresh, A., Jitha S Jayan, and Dr. Saritha A., “Modeling of dielectric properties of Chlorobutyl rubber nanocomposites”, Materials Today: Proceedings, vol. 18, pp. 3998-4003, 2019.[Abstract]

Chlorobutyl rubber comprises a significant type of butyl rubber with attractive properties. Inspection of the various aspects of the dielectric properties of chlorobutyl rubber nanocomposites containing organically modified layered silicates (nano clay) in a particular range of frequency was carried out at different filler loadings. Owing to the interaction of the organically modified silicate layers with the chlorobutyl rubber matrix, a conductive pathway is created which enables the improvement in the dielectric properties of the nanocomposites. A comparative study of the dielectric properties of composites containing various types of organically modified layered silicates was done. Modeling of the dielectric properties were done and the relevance of experimental results were evaluated with the existing models.

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2018

Journal Article

P. K. Sandhya, Jiya Jose, M.S. Sreekala, Prof. M. Padmanabhan, Nandakumar Kalarikkal, and Sabu Thomas, “Reduced graphene oxide and ZnO decorated graphene for biomedical applications”, Ceramics International, vol. 44, pp. 15092-98, 2018.[Abstract]

The ability of graphene-based materials to enhance the conventional antibiotic resistance is well known and researchers have been interested in improving their antibacterial activity. The reduction of graphene oxide by eco-friendly reducing agents is of great interest on the basis of environmental and human health aspects. Herein we report the synthesis of two forms of graphene derivatives namely, reduced graphene oxide (RGO) through reduction using potato starch and zinc oxide decorated RGO (ZnO-RGO). In the case of ZnO-RGO, the reduction of graphene oxide and the conversion of ZnO to nano ZnO occur simultaneously. The characterization of all the graphene based materials and nanocomposites developed were carried out using FT-IR, XRD, Raman spectra and TEM techniques. The antibacterial activity of these modified materials against E. coli was also studied by well diffusion method. Our results show that ZnO-RGO is more efficient than RGO in their antibacterial properties which we attribute to the synergistic effect of ZnO and RGO towards the bacteria in the nanocomposite. Further we find that the antibacterial effect of ZnO-RGO towards E. coli is due to the disruption of the bacterial cell which could be confirmed by AFM images. Considering the fact that graphene-based materials are less toxic towards mammalian cells, both RGO and ZnO-RGO we have developed can find applications in the field of medicine and life sciences.

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2018

Journal Article

M K Aswathi, Ajitha A R, L P Mathew, Prof. M. Padmanabhan, and S Thomas, “Selective localization of multi-walled carbon nanotubes in PTT/PE blends: theoretical analysis, morphology and mechanical properties”, Macromolecular Symposia , 2018.[Abstract]

Theoretical analysis is carried out to predict the nature of selective localization of multi‐walled carbon nanotubes (MWCNTs) in poly(trimethylene terephthalate/polyethylene (PTT/PE) blends. In agreement with theoretical data experimental results clearly indicate that MWCNT prefers to get associated with PTT phase than with PE. Molecular interactions responsible for such selective localization of MWCNT to PTT component can be attributed to mutual and collective π–π interactions possible between the aromatic moieties present in PTT and MWCNT. In addition, the reinforcing effect of MWCNT in the PTT/PE system was determined using tensile analysis and the morphological features of blends and blend nanocomposites are studied using scanning electron microscope (SEM). Compared to the PTT/PE blend system MWCNT incorporated blend nanocomposites show better mechanical properties. The elongation at break of the blend system is seen to rise with increasing amount of PE content. Among various blend nanocomposites, we have investigated the nanocomposites with higher PTT content show higher tensile strength and Young's modulus. The blend nanocomposite with 90/10/1 composition shows 12% increment in Young's modulus and as much as 80% increment in tensile strength compared to 90/10 blend system which signifies the role MWCNT plays in the blend system.

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2018

Journal Article

S. U. Varma, Gautham, P., Kumar, D. V. Ravi, Sreekanth, K. M., Sivasubramanian, G., and Sreedhar, K. M., “Co-Precipitation as a Tool for Effective Doping of Magnesium in Zinc Oxide: Studies on Structural, Optical and Photocatalytic Properties”, Rasayan Journal of Chemistry, vol. 11, pp. 1491-1500, 2018.[Abstract]

Elimination of toxic compounds from our essential commodities such as water, air, foods etc. and provision for safe and clean basic needs is currently one of the most significant international topics for research, especially in food, water and air pollution control. Metal oxides have emerged as one of the most interesting materials in the current period owing to their potential catalytic properties. The II-VI metal oxides are gaining considerable attention in optoelectronics and in rectifying environmental issues due to their ability to produce charge carriers when accelerated with a sufficient amount of energy. The electronic structure, fluorescence and phosphorescence properties and charge transport abilities of the metal oxides have made them photo catalysts. In this paper, we report a precise investigation of structural, optical and photo catalytic properties of industrially and technologically important ZnO and MgxZn(1-x)O nanoparticles. The materials were synthesized via chemical methods using solutions of zinc sulphate, sodium hydroxide, silver nitrate and magnesium sulphate. The structural, optical and photocatalytic properties of the synthesized samples were studied using X-ray diffractometer and UV-VIS spectrophotometer. The average crystallite size of the prepared samples is between 15 to 20 nm. The optical band value of the ZnO nanoparticles was found 3.3 eV. The photocatalytic studies were conducted using an in-house built assembly and photocatalytic degradation of Cr was chosen as a reference. The synthesized MgxZn(1-x)O has been observed as an excellent photocatalyst, and shown promising results for the degradation of Cr(VI).

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2018

Journal Article

V. Anjana, Sara John, Pooja Prakash, Amritha M Nair, Aravind R Nair, Sreedha Sambhudevan, and B. Shankar, “Magnetic Properties of Copper Doped Nickel Ferrite Nanoparticles Synthesized by Co Precipitation Method”, IOP Conference Series: Materials Science and Engineering, vol. 310, p. 012024, 2018.[Abstract]

Nickel ferrite nanoparticles with copper atoms as dopant have been prepared using co-precipitation method with general formula Ni 1-x Cu x Fe 2 O 4 (x=0.2, 0.4, 0.6, 0.8 and 1) and are sintered at quite ambient temperature. Structural and magnetic properties were examined using Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction method (XRD) and Vibrating Sample Magnetometer (VSM) to study the influence of copper doping in nickel ferrite magnetic nanoparticles. X-ray studies proves that the particles are possessing single phase spinel structure with an average particle size calculated using Debye Scherer formula. Magnetic measurements reveal that saturation magnetization value (M s ) decreases while magnetic coercivity (H c ) increases upon doping.

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2018

Journal Article

Sankar S. Menon, Radhu Krishna, Lida Wilson, Sreedha Sambhudevan, B. Shankar, Anshida Mayeen, and Nandakumar Kalarikkal, “Magnetic and dielectric properties of nickel-ferrite-embedded natural rubber composites”, Polymer Bulletin, vol. 75, pp. 5217–5234, 2018.[Abstract]

Spinel-structured nickel ferrite has been prepared using co-precipitation method. The ferrite particles prepared were characterized using XRD, FTIR, and TEM and were confirmed to be in the nano-regime. Natural rubber composites were prepared with different loadings of nickel ferrite like 5, 15, 25, 50, and 75 (in part per hundred rubber, phr). The mechanical, swelling, and magnetic properties were analyzed using the standard methods. Dielectric measurements show that permittivity decreases with increase in frequency and increases with increase in ferrite loading. Tan delta value also was found to increase with filler loading which may be attributed to the presence of interfacial polarization.

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2018

Journal Article

Athira Krishnan and S.M.A. Shibli, “Optimization of an Efficient, Economic and Eco-friendly Inhibitor based on Sesbania Grandiflora Leaf Extract for the Mild Steel Corrosion in Aggressive HCl Environment”, Anti-Corrosion Methods and Materials, vol. 65, no. 2, pp. 210–216, 2018.[Abstract]

Purpose
This paper aims to evaluate the inhibitive action of different concentrations of Sesbania grandiflora leaf extract on the mild steel corrosion in an aggressive HCl medium under different experimental conditions.
Design/methodology/approach
Weight loss investigation, open-circuit voltage analysis, Tafel polarisation, AC impedance analysis, etc. were used for the evaluation of inhibition efficiency. The influence of immersion period on inhibition efficiency was evaluated. The mechanism of action of the inhibitor is also discussed. Infrared (IR) spectroscopy and energy-dispersive X-ray spectroscopy analysis were used to characterise the passive film.
Findings
The results suggested that 10,000 ppm solution has maximum inhibition efficiency of 98.01 per cent at room temperature, while 1,000 ppm solution also exhibited a better efficiency of about 96.16 per cent. Efficiency of inhibitor solution was found to increase with an increase in its concentration. Polarisation study proposed the solution as an anodic inhibitor. Impedance study confirmed the formation of a protective layer over the surface of the specimen, and the constituents of the film were identified using IR spectroscopy. Stability of the film adsorbed on the steel was cleared from the steady open-circuit potential value. Study on action of the inhibitor under accelerated conditions revealed the fact that the efficiency of extract in preventing corrosion is good under stimulated conditions also.
Practical implications
The action of inhibitor sustains for a sufficient time period and could sustain under stimulated conditions. Hence, its application is practically possible in industries. The proposed inhibitor is widely available and is environmentally safe.
Originality/value
HCl is an industrially important chemical used for acid cleaning, acid pickling, etc. HCl was used as an aggressive corrosion environment. As the chances for mild steel to be in contact with HCl were very high, it was important to develop an efficient, economical and eco-friendly inhibitor for corrosion.

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2018

Journal Article

Nayana Krishna, Nandakumar G., Neethu T S, Rini John, Sudheesh. R. Babu, and Dr. Smitha Chandran S., “One Pot Green Synthesis of Silver Nanoparticles with Multiple Applications”, Materials Today: Proceedings, vol. 5, pp. 20567–20571, 2018.[Abstract]

Cost effective chemosensors were developed from green synthesized silver nanoparticles using Leucas indica and were characterized with surface Plasmon Resonance (SPR) UV Spectrometry. The sensitivity and selectivity of green synthesized silver nanoparticles towards transition metal ions and alkaline earth metals were studied. Applications such as antimicrobial activity and the ability of formed stable nanoparticle to act as chemosensors are also studied. UV studies confirmed the presence of silver nanoparticles by their characteristic peak in range of 436-446nm. Ag NPs also showed antimicrobial activities with gram negative (Escherichia coli) microorganisms.

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2018

Journal Article

A Santhy and Rejithamol, R., “Phosphorus species in core sediment and its relation with sediment characteristics of paravur estuary, south west coast of India”, 2018Rasayan Journal of chemistry, vol. 11, pp. 1067 - 1073 , 2018.[Abstract]

The core sediment from two distinct zones of the Paravur estuary, one from the sea water influenced western region and other from the river water influenced eastern region were selected for estimating the different species of phosphorus. The concentration of different species of phosphorus along with iron, organic carbon and textural quality from different sediment depths of the above two locations were investigated. The average value of total phosphorus was found to be higher in fresh water influenced region than marine influenced region. Total phosphorus shows a strong positive correlation with organic carbon in both regions

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2018

Journal Article

Pawan K Pandey, Ashok K Sharma, Sarita Rani, Gaurav Mishra, Dr. Gopal K., Ajit K Patra, Monika Rana, Anuj K Sharma, Awesh K Yadav, and Umesh Gupta, “MCM-41 Nanoparticles for Brain Delivery: Better Choline-Esterase and Amyloid Formation Inhibition with Improved Kinetics”, ACS Biomaterials Science & Engineering, vol. 4, pp. 2860–2869, 2018.[Abstract]

The present study was aimed at delivering a low bioavailability drug, rivastigmine hydrogen tartrate (RTG), to the brain through its encapsulation in mesoporous silica nanoparticles (MSNs) and targeted to amyloid inhibition in the brain. MSNs were characterized for size, zeta potential, and drug entrapment using SEM, TEM, HR-TEM, FT-IR, and PXRD. Drug-loaded MSNs were assessed for in vitro release kinetics and ex vivo followed by animal studies. The average size of the prepared blank (MCM-41B) and drug-loaded MSNs (MCM-41L) was 114 ± 2.0 and 145 ± 0.4 nm with the zeta potential of approximately −43.5 ± 1.1 and −37.6 ± 1.4 mV, respectively. MCM-41L exhibited an average entrapment efficiency of 88%. In vitro release studies exhibited early surge followed by a sluggish persistent or constant release (biphasic pattern). Hemolytic studies proved that the developed MCM-41L NPs are less hemolytic compared to RTG. A reduced ThT fluorescence was observed with MCM-41L compared to MCM-41B and RTG in the amyloid inhibition studies. A significant (p < 0.05) inhibition of AChE (acetycholinesterase) was observed for MCM-41L (80 ± 4.98%), RTG (62 ± 3.25%), and MCM-41B (54 ± 4.25%). In vivo pharmacokinetics in Wistar rats revealed that the AUC and mean residence time (MRT) for MCM-41L was sustained and significantly higher (p < 0.05) (780 ± 3.30 ng/L; 5.49 ± 0.25 h) compared to RTG solution (430 ± 3.50 ng/L; 0.768 ± 0.17 h). Similarly, the half-life was found to be significantly higher in case of MCM-41L. The promising result was brain delivery of RTG in Wistar rats which was enhanced almost 127 folds in vivo, using MCM-41L nanoparticles. MCM-41L nanoparticles effectively enhanced the bioavailability of RTG. Conclusively, these can be used for the administration of RTG and other related low bioavailability drugs for improved brain delivery.

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2018

Journal Article

R. Rejithamol, Dr. Beena S., A Santhy, and Asha B Nair, “Synthesis, Characterization and Photophysical Properties of Benzylidene-Fluorene Derivatives”, International Conference on Materials Processing and Characterization, vol. 5, no. 9, pp. 17694-17698, 2018.[Abstract]

A convenient and rapid method for the synthesis of benzylidene-fluorene from aromatic aldehydes and fluorene in presence of 1, 8-diazobicyclo [5,4,0] undec-7-ene (DBU) as an organic catalyst at room temperature giving good yields, short reaction time and easy isolation. Fluorene based π-conjugated organic compounds have found dominant usance that bring about them deserved entrant for utilizations in organic optoelectronic devices and chemical sensors. The report high points an approach to synthesize these materials and to study the photophysical properties

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2018

Journal Article

Gopakumar Karthik, A Harith, N Nazrin Thazleema, Shaji Vishal, S Jayan Jitha, and Dr. Saritha A., “One step approach towards the green synthesis of silver decorated graphene nanocomposites for the degradation of organic dyes in water”, IOP Conference Series: Materials Science and Engineering, vol. 310, p. 012034, 2018.[Abstract]

Recently the decoration of graphene with metallic nanoparticles by a one pot reduction of graphene oxide (GO) coupled with the synthesis of metallic nanoparticles has gained momentum. Graphene and GO have been proved to exhibit excellent biocompatibility and high antibacterial activity and hence a vast possibility lies in the utilization of GO as an antibacterial reinforcement in biomaterials and exploration of the antiseptic properties as well as the cytotoxicity of GO-containing composites. Moreover GO decorated with metal / metal oxide paves way towards an inevitable role in water purification. The use of graphene oxide as the nano scale substrates for the development of nanocomposites with metal oxides is a novel idea to obtain a hybrid which would exhibit both the properties of GO as a enthralling paper-shape material and the quality of single nano-sized metal particles. The heavy metal ions and pollutants are considered as a major problem in environmental contamination. Hence detection of trace level pollutant has become a hot topic in the present research scenario. Modified graphene oxide nanocomposites prepared using a green approach has the capacity of absorbing pollutant material ions in high efficiency and selectivity. The green synthesized nanocomposites were characterized using FTIR and UV spectroscopy and the consequence of pH and concentration on the preparation of the nanocomposites was evaluated. The efficiency of these nanocomposites towards degradation of organic dyes like methylene blue has been evaluated.

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2018

Journal Article

Dr. Naveen V. Kulkarni, William W. Brennessel, and William D. Jones, “Catalytic Upgrading of Ethanol to n-Butanol via Manganese-Mediated Guerbet Reaction”, ACS Catalysis, vol. 8, pp. 997-1002, 2018.[Abstract]

Replacement of precious metal catalysts in the Guerbet upgrade of ethanol to n-butanol with first-row metal complex catalysts is highly appreciated due to their economic and environmental friendliness. The manganese pincer complexes of the type [(RPNP)MnBr(CO)2] (R = iPr, Cy, tBu, Ph or Ad) are found to be excellent catalysts for upgrading ethanol to n-butanol. Under suitable reaction conditions and with an appropriate base, about 34% yield of n-butanol can be obtained in high selectivity. A detailed account on the effect of the temperature, solvent, nature, and proportion of base used and the stereoelectronic effects of the ligand substituents on the catalytic activity of the catalysts as well as the plausible deactivation pathways is presented.

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2018

Journal Article

A. M. Kunjappan, Poothanari, M. A., Ramachandran, A. A., Prof. M. Padmanabhan, Mathew, L., and Thomas, S., “High-performance electromagnetic interference shielding material based on an effective mixing protocol”, Polymer International, 2018.[Abstract]

Abstract A facile and economic method is developed for the fabrication of new lightweight materials with high electromagnetic interference (EMI) shielding performance, good mechanical properties and low electrical percolation threshold through melt mixing. Electrical properties, DC conductivity, EMI shielding performance and mechanical properties of poly(trimethylene terephthalate) (PTT)/multiwalled carbon nanotube (MWCNT) nanocomposites with varying filler loading of MWCNTs were investigated. High-resolution transmission electron microscopy was used to determine the distribution of MWCNTs in the PTT matrix. The newly developed nanocomposites show excellent dielectric and EMI shielding properties. Theoretical electrical percolation threshold was achieved at 0.21 wt% loading of MWCNTs, due to the high aspect ratio and the three-dimensional network formation of MWCNTs. Experimental DC conductivity values were compared with those of theoretical models such as the Voet, Bueche and Scarisbrick models, which showed good agreement. The PTT/3% MWCNT composite showed an EMI shielding value of ∼38 dB (99.99% attenuation) with a sample thickness of 2 mm. Power balance was used to determine the actual contribution of reflection, absorption and transmission loss to the total EMI shielding value. The nanocomposites showed good tensile and impact properties and the composite with 2% MWCNTs exhibited an improvement in tensile strength of as much as 96%. © 2018 Society of Chemical Industry

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2018

Journal Article

A. Santhy, Dr. Beena S., P. Sankar, U., Vidya, R., and Rejithamol, R., “PVC membrane Sensor Immobilized with Clopidogrel-Tetraiodo Bismuthate for the Potentiometric Determination of Clopidogrel from Pharmaceutical Formulations”, Materials Today: Proceedings, vol. 5, pp. 17812 - 17819, 2018.[Abstract]

This paper describes the fabrication of potentiometric PVC membrane for clopidogrel bisulphate and its successful utilization in the determination clopidogrel from clopilet tablet. Effect of PVC membrane matrix were studied and optimized membrane composition which ensued a Nernstian slope of 58.83±0.340mV/decade was found to be PVC 32%, ion association 3%,NaTBP 2% and DBP 63 % respectively. Sensor revealed a fast response time of 3s in the concentration range 1×10-2 -1×10-6 M with a lower detection limit of 9.12 ×10-7M. Working pH range and response time was found to be 2.0 - 4.5 and 5s respectively. Comparative studies on the various parameters that depend on the potential response of the present sensor with that of the literature reports were also included

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2018

Journal Article

Divya Mohan R and Jose, A., “Reactions of Huisgen Zwitterions with Diphenyl Cyclopropenone: A Novel Strategy for the Synthesis of Oxazinone Derivatives”, Asian Journal of Chemistry, vol. 30, pp. 1075-1077, 2018.[Abstract]

In synthetic organic chemistry carbon hetero-atom and carbon carbon bond forming reactions are of prior importance. Generally polar and pericyclic reaction strategies are used for this which utilize reactive intermediates like carbanions, enols, radicals, carbenes, zwitterions, etc. Although potentially very useful, zwitterions have received less attention from this perspective. The present work is concerned with the use of a less well-known reactive intermediate viz., zwitterion. Neutral nucleophiles like triphenyl phosphine, nucleophilic carbenes, and isocyanides can form zwitterionic intermediates with azodicarboxylates and activated acetylenes [1-4]. Although, phosphine-azoester zwitterion generally known as the Huisgen zwitterion [5], has been known in the literature for almost five decades, barring its use as nucleophilic trigger in the Mitsunobu reaction [6-8]. The chemistry of these powerful reactive intermediates remained largely unexplored. In recent years, our research group has explored the synthetic potential of these zwiterionic intermediates with a view to synthesize a variety of heterocycles [1,2] and uncovered the interesting reactivity patterns of the zwitterions generated from triphenyl phosphine and dialkyl azodicarboxylate. In continuation these studies, presently, we investigated the reactions of Huisgen zwitterions derived from triphenylphosphine-azodicarboxylate with diphenyl cyclopropenones leading to the formation of oxazinones. Cyclopropenones are an important class of compounds because of their application in a wide range of reactions such as decarbonylation, addition, oxidation, substitution reactions, etc. Further, the variety of reactions for such a simple Reactions of Huisgen Zwitterions with Diphenyl Cyclopropenone: A Novel Strategy for the Synthesis of Oxazinone Derivatives

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2017

Journal Article

G. George, K. Joseph, Dr. Saritha A., and E. R. Nagarajan, “Influence of fiber content and chemical modifications on the transport properties of PP/jute commingled biocomposites”, Polymer Composites, 2017.[Abstract]

This article aims at the investigation of the effect of five different parameters on the transport behavior of PP/jute yarn commingled eco-composites. The high affinity of jute yarns to moisture (hydrophilic nature) favored the water absorption whereas xylene and toluene diffusion through PP/jute commingled system reduced with increasing fiber content. Chemical treatments increased the interfacial adhesion between the matrix and jute yarns resulting in lesser number of voids and other irregularities at the interface and also resulted in a reduction in the hydrophilic tendency of jute yarns. This led to a decrease in apparent weight gain % with different treatments. The activation energy for the solvent xylene increased with the increase in fiber content owing to the hindering of motion of the solvent molecules by the reinforcing jute yarns whereas for the solvent water, the activation energy decreases with increase in fiber content due to the hydrophilic nature of jute yarns. The analysis of mechanism of transport revealed that the diffusion of water through the composites very nearly follow Fickian mode of transport whereas for the solvent xylene it deviates from it. © 2017 Society of Plastics Engineers.

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2017

Journal Article

S. Thamban, U, A., Padmanabhan, M., and Nath, R. Chandra, “Structural and magnetic properties of spin-$1/2$ dimer compound Cu$_2$(IPA)$_2$(DMF)(H$_2$O) with a large spin gap.”, J Phys Condens Matter, 2017.[Abstract]

<p>We present the synthesis and a detailed investigation of structural and magnetic properties of metal-organic compound Cu$_2$(IPA)$_2$(DMF)(H$_2$O) by means of x-ray diffraction, magnetization, and heat capacity measurements. Single crystals of the title compound were synthesized by judicious selection of organic ligand and employing a selective hydrothermal reaction route. It crystallizes in an orthorhombic structure with space group $Cmca$. The structural analysis revealed that two Cu$^{2+}$ ions are held together by the organic component (-O-C-O-) in a square paddle-wheel to form spin dimers which are aligned perpendicular to each other and are further coupled through organic ligands (isophthalic acid) forming two-dimensional layers. Temperature dependent magnetic susceptibility $\chi(T)$ could be described well using spin-$1/2$ dimer model. The spin susceptibility $\chi_{\rm spin} (T)$ shows an exponential decrease in the low temperature region, below the broad maximum, confirming the singlet ground state with a large spin gap of $\Delta/k_{\rm B} \simeq 409$~K. The heat capacity $C_{\rm p}$ measured as a function of temperature also confirms the absence of magnetic long-range-order down to 2~K.</p>

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2017

Journal Article

S. Thamban, U. Arjun, Prof. M. Padmanabhan, and R. C. Nath, “Structural and magnetic properties of spin-1/2 dimer compound Cu2(IPA)2(DMF)(H2O) with a large spin gap”, Journal of Physics: Condensed Matter: an Institute of Physics journal, vol. 29, 2017.[Abstract]

We present the synthesis and a detailed investigation of structural and magnetic properties of metal-organic compound Cu2(IPA)2(DMF)(H2O) by means of x-ray diffraction, magnetization, and heat capacity measurements. Single crystals of the title compound were synthesized by judicious selection of organic ligand and employing a selective hydrothermal reaction route. It crystallizes in an orthorhombic structure with space group Cmca. The structural analysis revealed that two Cu2+ ions are held together by the organic component (-O-C-O-) in a square paddle-wheel to form spin dimers which are aligned perpendicular to each other and are further coupled through organic ligands (isophthalic acid) forming two-dimensional layers. Temperature dependent magnetic susceptibility χ(T)could be described well using spin-1/2 dimer model. The spin susceptibility χspin(T)shows an exponential decrease in the low temperature region, below the broad maximum, confirming the singlet ground state with a large spin gap of Δ/kB ≃ 414 K. The heat capacity Cp measured as a function of temperature also confirms the absence of magnetic long-range-order down to 2 K. © 2017 IOP Publishing Ltd.

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2017

Journal Article

R. Rejithamol, K. Aparna, S. Swetha, A. Gayathri, and S. Jisha, “A facile synthesis of α-hydrazino ketones from 1,3-dicarbonyl compounds using 1,8-diazobicyclo[5.4.0]undec-7-ene (DBU) as organic catalyst”, Asian Journal of Chemistry, vol. 29, pp. 1963-1965, 2017.[Abstract]

A convenient and rapid method for the synthesis of α-hydrazino ketones from 1,3-dicarbonyl compounds and diethyl azodicarboxylate in presence of 1,8-diazobicyclo[5.4.0]undec-7-ene as an organic catalyst at room temperature giving good yields, short reaction time and easy isolation. © 2017, Chemical Publishing Co. All rights reserved.

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2016

Journal Article

S. Sankar, B.N. Nair, T. Suzuki, G.M. Anilkumar, Prof. M. Padmanabhan, U.N.S. Hareesh, and K.G.K. Warrier, “Hydrophobic and metallophobic surfaces: Highly stable non-wetting inorganic surfaces based on lanthanum phosphate nanorods”, Scientific Reports (Nature Publishing Group), vol. 6, 2016.[Abstract]

Metal oxides, in general, are known to exhibit significant wettability towards water molecules because of the high feasibility of synergetic hydrogen-bonding interactions possible at the solid-water interface. Here we show that the nano sized phosphates of rare earth materials (Rare Earth Phosphates, REPs), LaPO 4 in particular, exhibit without any chemical modification, unique combination of intrinsic properties including remarkable hydrophobicity that could be retained even after exposure to extreme temperatures and harsh hydrothermal conditions. Transparent nanocoatings of LaPO 4 as well as mixture of other REPs on glass surfaces are shown to display notable hydrophobicity with water contact angle (WCA) value of 120° while sintered and polished monoliths manifested WCA greater than 105°. Significantly, these materials in the form of coatings and monoliths also exhibit complete non-wettability and inertness towards molten metals like Ag, Zn, and Al well above their melting points. These properties, coupled with their excellent chemical and thermal stability, ease of processing, machinability and their versatile photo-physical and emission properties, render LaPO 4 and other REP ceramics utility in diverse applications.

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2016

Journal Article

Ua Arjun, Brinda, Ka, Padmanabhan, Mb, and Nath, Ra, “Magnetic properties of layered rare-earth oxy-carbonates Ln2O2CO3 (Ln=Nd, Sm, and Dy)”, Solid State Communications, 2016.[Abstract]

Polycrystalline samples of rare-earth oxy-carbonates Ln 2O2CO3 (Ln=Nd, Sm, and Dy) are synthesized and their structural and magnetic properties are investigated. All of them crystallize in a hexagonal structure with space group P63/mmc. They form a double layered structure with frustrated triangular arrangement of rare-earth magnetic ions. An antiferromagnetic transition is observed at TN 1.25K,0.61K, and 1.21K for Nd2O2CO3, Sm2O2CO3, and Dy2O2CO3, respectively. From the analysis of magnetic susceptibility, the value of the Curie-Weiss temperature θCW is obtained to be  21.7K, 18K, and 10.6K for Nd2O2CO3, Sm2O2CO3, and Dy2O2CO3, respectively. The magnetic frustration parameter f(=|θCW|/TN) is calculated to be  17.4, 31, and 8.8 for Nd2O2CO3, Sm2O2CO3, and Dy2O2CO3, respectively, which indicates that Sm2O2CO3 is strongly frustrated compared to its Nd and Dy analogues. © 2016 Elsevier Ltd. More »»

2016

Journal Article

B. Costa, Dr. Milind Shrinivas, Vetro, M., Donvito, G., Gabrielli, L., Amigoni, L., Cassinelli, G., Lanzi, C., Ceriani, M., De Gioia, L., Filippi, G., Cipolla, L., Zaffaroni, N., Perego, P., and Colombo, D., “Synthetic sulfoglycolipids targeting the serine–threonine protein kinase Akt”, Bioorganic and Medicinal Chemistry, vol. 24, pp. 3396-3405, 2016.[Abstract]

The serine–threonine protein kinase Akt, also known as protein kinase B, is a key component of the phosphoinositide 3-kinase (PI3K)–Akt–mTOR axis. Deregulated activation of this pathway is frequent in human tumors and Akt-dependent signaling appears to be critical in cell survival. PI3K activation generates 3-phosphorylated phosphatidylinositols that bind Akt pleckstrin homology (PH) domain. The blockage of Akt PH domain/phosphoinositides interaction represents a promising approach to interfere with the oncogenic potential of over-activated Akt. In the present study, phosphatidyl inositol mimics based on a β-glucoside scaffold have been synthesized as Akt inhibitors. The compounds possessed one or two lipophilic moieties of different length at the anomeric position of glucose, and an acidic or basic group at C-6. Docking studies, ELISA Akt inhibition assays, and cellular assays on different cell models highlighted 1-O-octadecanoyl-2-O-β-D-sulfoquinovopyranosyl-sn-glycerol as the best Akt inhibitor among the synthesized compounds, which could be considered as a lead for further optimization in the design of Akt inhibitors. © 2016 Elsevier Ltd

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2016

Journal Article

Sreedha Sambhudevan, Balakrishnan Shankar, Dr. Saritha A., and Kuruvilla Joseph, “Evaluation of Kinetics and Transport Mechanism of Solvents Through Natural Rubber Composites Containing Organically Modified Gadolinium Oxide”, Plastics, Rubber and Composites-Macromolecular Engineering, vol. 45, pp. 216 - 223, 2016.[Abstract]

The solvent transport properties of the prepared composites were analysed using solvents of varying cohesive energy density and the effect of both modified as well as unmodified filler on the sorption and diffusion behaviour of NR vulcanisates has been investigated. It is found that the equilibrium uptake decreases with increase in filler content, as anticipated owing to the restrictions offered by the filler for solvents to diffuse into the polymer matrix. The mechanism of transport in natural rubber composites was carefully tracked and it was found to exhibit an anomalous mode of solvent transport where the polymer relaxation is in par with the rate of diffusion. Theoretical modelling of the swelling parameters was done and the results were found to be in agreement with existing models. The excellent swelling resistance coupled with the simultaneous improvement in mechanical properties would definitely pave way for the utilisation of these composites as barrier membranes.

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2016

Journal Article

Dr. Beena S. and Krishnapillai Girish Kumar, “PVC Membrane Sensor for Nd (III) Based on N 1 , N 2 -Bis (Salicylidine) Butane-1, 4 -Diamine”, International Journal of Advanced Research in Chemical Science (IJARCS), vol. volume 3, no. Issue 2, 2016.[Abstract]

N 1 , N2 -bis(salicylidine)butane-1,4-diamine (SAB ) based PVC membrane sensor was fabricated for Nd(III). The developed sensor showed nernstian response in the concentration range of 1.0×10-6 to 1.0×10-1 M. Nernstian slope of the proposed sensor was found to be 20.6±0.3 mV/decade in the pH range 3.0 to 7.5. The developed sensor displays a response time of <15 s. The proposed sensor can be used over a period of 7 weeks without any significant changes in its Nerstian behaviour. The sensor showed good selectivity for neodymium when compared with other metal ions such as Na+ , K+ , Mg2+, Ca2+, Pb2+, Ag+ , Pr3+ , Sm3+, La3+, and Gd3+. This electrode was used as an indicator electrode in the potentiometric titration of neodymium ions with EDTA and was also applied in the determination of neodymium in binary mixture. More »»

2016

Journal Article

Dr. Smitha Chandran S., Peter Ash, and Anju Bist, “Managing Former Landfill Sites a Case Study of Ecorestoration from Kochi, Kerala”, Green Chemistry & Technology Letters, vol. 1, pp. 82–85, 2016.[Abstract]

This paper describes the dramatic success in the eco-restoration of a heavy-metal contaminated open garbage dump at the Amrita Institute of Medical Sciences (AIMS), a 1450-bed super-specialty hospital located in Kochi, Kerala, India. Today, the hospital caters to over 10 lakh patients annually. Inspired by our Chancellor’s vision of zero-waste, the hospital undertook its journey with a view to also reducing massive greenhouse gas emissions that result from improper handling of waste. Today, the hospital manages its municipal solid waste on an industrial scale, composting some eight metric tonnes of organic waste daily.This case study outlines the path followed to achieve zero-waste. Alongside, the rehabilitation of a former dump site is described in detail at this very site are carried out all composting operations of AIMS. Within three years of the restoration activities, heavy metal concentrations in the contaminated soil reduced drastically.There was relatively low uptake of the heavy metals by the plants; however, they might have been crucially responsible for providing a favorable environment for soil restoring microorganisms in their rhizosphere. Observable habitat-restoration continues at the site, including the return of birds and insects and other wildlife, making this an ideal site for further research and demonstration for community awareness and education. More »»

2015

Journal Article

Jennifer K. Molloy, Dr. Zeena S. Pillai, Junji Sakamoto, Paola Ceroni, and Giacomo Bergamini, “Lanthanide Terpyridine-Based Assemblies: Towards Dual Luminescent Probes”, Asian Journal of Organic Chemistry, vol. 4, pp. 251–255, 2015.

2015

Journal Article

Sreedha Sambhudevan, “Synthesis and characterization of organically modified gd2o3 - natural rubber composites as effective x-ray shielding materials”, Green Chemistry & Technology Letters, vol. 1, pp. 86–91 , 2015.[Abstract]

Protective materials based on lead are the usual X- ray shielding materials but their extended use leads to severe health problems due to the toxic nature of lead. Moreover, lead based materials are not appropriate for absorbing the regular energy region of X-ray used in medical field and hence natural rubber composites containing modified Gadolinium oxide (Gd2O3) as filler is suggested as an alternative. Natural rubber composites were prepared with organically modified Gd2O3 at various filler loadings.The structural features of modified Gd2O3 were examined using FTIR, X-ray diffraction and SEM. The particle size of organically modified Gd2O3 was found to be in the nano range which contributes to the enhanced properties of the composites. The increase of filler loading improved the shielding effectiveness of the rubber composites. Examination of mechanical and X-ray shielding properties show the effectiveness of the material to be used as potential shielding materials. More »»

2015

Journal Article

Aarathi Krishna, Sreejisha T Nair, Dr. Smitha Chandran S., and Dr. Saritha A., “From biowastes to novel nanomaterials: A one pot green synthesis of nanoparticles towards the naked eye detection of metals ”, International Journal of Applied Engineering Research, vol. 10, 2015.[Abstract]

Green nanotechnology has gained momentum in the recent years because it couples the immense applications of nanotechnology with the principles of green chemistry so that the toxic effects of nanotechnology stands nullified. The environmental as well as health issues of nanotechnology has only been addressed in the recent times and since then the green pathway towards the synthesis of nanoparticles has gained immense attention. The novel phenomenon of surface Plasmon resonance exhibited by metallic nanoparticles has been exploited and silver nanoparticles were prepared from biowastes like cashew peel, tapioca peel, banana bosom peel etc which would otherwise appear as waste in and around the processing centers. The aforementioned nanoparticles were characterized by UV spectroscopy and the behavior of these particles towards naked eye detection of selected heavy metal ions like nickel, cadmium,lead and mercury were observed. More »»

2015

Journal Article

Dr. Smitha Chandran S. and E. V. Ramasamy, “Utilization of Limnocharis flava, an invasive aquatic weed from Kuttanad wetland ecosystem, kerala, india as a potential feedstock for livestock”, Online Journal of Animal and Feed Research , vol. 5, no. 1, pp. 22-27, 2015.[Abstract]

The chemical composition, nutritive value and trace element profiles of Limnocharis flava, an emergent aquatic weed during its different growth stages was determined to evaluate as possible cattle feed. Samples were analyzed at three progressive morphological stages of the plant, pre-flowering, flowering and post-flowering. The moisture content, dry matter (DM), ash content, crude protein (CP), ether extract (EE), crude fiber (CF), nitrogen free extract (NFE) and mineral constituents like sodium (Na+) potassium (K+), calcium (Ca2+), phosphorous (P) and trace elements like iron (Fe2+), copper (Cu2+), manganese (Mn2+), zinc (Zn2+), lead (Pb2+), chromium (Cr2+ ) nickel (Ni+) and cadmium (Cd+) contents were analyzed. The moisture content, organic matter (OM), acid detergent fiber content increased during maturation, while CP and EE were found decreased with increased growth stage. Only slight fluctuations occurred in Calcium, Potassium, Phosphorous and Sodium contents. The highest values for crude protein, fiber content, NFE and EE were observed at the flowering stage. These plant posses several characteristics which makes it a nutritious feed suitable for domestic livestock, and is recommended to use L.flava, particularly at the flowering stage of growth. More »»

2015

Journal Article

Ananthika V, Sreedha Sambhudevan, and Sanker, B., “Mechanical, Swelling and Magnetic property studies of Natural rubber-Nickel ferrite composites”, International Journal of Applied Engineering Research, vol. 10, 2015.[Abstract]

Polymers are usually non-magnetic in nature. The introduction of magnetic materials imparts magnetic properties to the polymer as well as improves the physical properties of polymer/rubber matrix. The merits of polymer bonded magnets (PBMs) over their metallic and ceramic counterparts comprise low weight, resistance to corrosion, ease of fabrication and capability for high production rates. In the present work nickel ferrite was prepared by coprecipitation method. The prepared ferrite fillers are embedded in natural rubber (NR) matrix by mechanical mixing at different loadings to get the rubber ferrite composites (RFCs) and their properties were studied as a function of filler loading from 0-75 phr. The mechanical property study reveals that tensile strength, elongation at break and modulus (100%) increases up to 25 phr of filler loading and afterwards it shows a marginal fall, but Shore hardness significantly increases with filler loading. The magnetic measurements were done on the filler and prepared RFCs. The results show that there is a significant improvement in the coercivity, magnetic retentivity and saturation magnetization and is linearly dependent on the filler amount. The solvent diffusion study shows that the equilibrium solvent uptake decreases with increase in filler content which is in accordance with mechanical and magnetic studies. More »»

2014

Journal Article

Aab Saritha and Joseph, Kb, “Role of solvent interaction parameters in tailoring the properties of chlorobutyl rubber nanocomposites”, Polymer Composites, 2014.[Abstract]

Chlorobutyl rubber, a special class of butyl rubber, which exhibits superior air impermeability, is the elastomer of choice for the inner tubes and liners of tires. Chlorobutyl rubber nanocomposites containing layered silicates were prepared using solvents with varying cohesive energy density and the effect of solvent-clay and solvent-rubber parameters in determining the properties of the nanocomposites were studied. The nanocomposites so prepared were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results were interpreted with the help of thermodynamic concepts and a correlation between the mechanical properties of the nanocomposites and the difference in the interaction parameters was done. The same correlation was then applied to gas barrier properties and trends identical to mechanical properties were observed. Thereby it was shown that a strong relationship exists between properties of a system and solubility parameters in solution mixing process. © 2014 Society of Plastics Engineers.

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2014

Journal Article

Akhil Sivan and A. Deepthi, “Facile synthesis of 1,2,3-tricarbonyls from 1,3-dicarbonyls mediated by cerium(IV) ammonium nitrate”, Tetrahedron Letters, vol. 55, pp. 1890-1893, 2014.[Abstract]

A mild and efficient protocol for the synthesis of vicinal tricarbonyl compounds from β-dicarbonyls in a single step using cerium(IV) ammonium nitrate as a catalytic oxidant is described. Ease of execution, wide substrate scope and the suitability for the synthesis of commercially important compounds like ninhydrin, alloxan and oxoline make this reaction particularly noteworthy. More »»

2014

Journal Article

Dr. Saritha A. and Kuruvilla Joseph, “Immobilizing polymer chains in chlorobutyl rubber nanocomposites”, Society of Plastics Engineers (SPE), 2014.[Abstract]

The varying organic modification, lattice spacing, and concentration of added nanoclays have a profound effect on the constrained polymer volume in chlorobutyl rubber nanocomposites. More »»

2013

Journal Article

Dr. Zeena S. Pillai, P. Ceroni, M. Kubeil, J.-M. Heldt, H. Stephan, and G. Bergamini, “Dendrimers as Nd3+ ligands: Effect of generation on the efficiency of the sensitized lanthanide emission”, Chemistry - An Asian Journal, vol. 8, pp. 771-777, 2013.[Abstract]

We have designed two novel dendrimers with cyclam cores with appended poly(amido amine) (PAMAM) dendrons, decorated at the periphery with four and eight dansyl chromophores, respectively. The photophysical properties of the dendrimers and their Nd3+ complexes have been investigated. The energy-transfer efficiency to the lanthanide ions from these dendrimers has been studied as a function of the generation. It has been observed that an increase in the dendrimer generation as well as the number of amide units enhances the energy transfer to the lanthanide ion. Shine on: Two novel cyclam-core-based dendrimers with appended poly(amido amine) (PAMAM) dendrons, decorated at the periphery with four and eight dansyl chromophores, respectively, have been synthesized and characterized. Upon titration with Nd3+ it has been observed that an increase in the dendrimer generation as well as the number of amide units enhances the efficiency of the energy transfer to the lanthanide ion. Copyright © 2013 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim.

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2013

Journal Article

R. Nath, A A Tsirlin, P Khuntia, O Janson, T Forster, Prof. M. Padmanabhan, J Li, Yu Skourski, M Baenitz, H Rosner, and I. Rousochatzakis, “Magnetization and spin dynamics of the spin S=1/2 hourglass nanomagnet Cu 5 (OH) 2 (NIPA) 4 10H 2 O”, Physical Review B, vol. 87, p. 214417/115, 2013.[Abstract]

We report a combined experimental and theoretical study of the spin S=12 nano magnet Cu5(OH)2(NIPA)4⋅10H2O (Cu5-NIPA). Using thermodynamic, electron spin resonance, and 1H nuclear magnetic resonance measurements on one hand, and ab initio density-functional band-structure calculations, exact diagonalizations, and a strong-coupling theory on the other, we derive a microscopic magnetic model of Cu5-NIPA and characterize the spin dynamics of this system. The elementary fivefold Cu2+ unit features an hourglass structure of two corner-sharing scalene triangles related by inversion symmetry. Our microscopic Heisenberg model comprises one ferromagnetic and two antiferromagnetic exchange couplings in each triangle, stabilizing a single spin S=12 doublet ground state (GS), with an exactly vanishing zero-field splitting (by Kramers' theorem), and a very large excitation gap of Δ≃68 K. Thus, Cu5-NIPA is a good candidate for achieving long electronic spin relaxation (T1) and coherence (T2) times at low temperatures, in analogy to other nanomagnets with low-spin GS's. Of particular interest is the strongly inhomogeneous distribution of the GS magnetic moment over the five Cu2+ spins. This is a purely quantum-mechanical effect since, despite the non frustrated nature of the magnetic couplings, the GS is far from the classical collinear ferrimagnetic configuration. Finally, Cu5-NIPA is a rare example of a S=12 nano magnet showing an enhancement in the nuclear spin-lattice relaxation rate 1/T1 at intermediate temperatures.

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2013

Journal Article

M. S. Suresh and Prof. M. Padmanabhan, “Synthesis and characterization of axially linked heteroleptic polymeric and monomeric lewis base adducts of BIS-(2-mercaptobenzothiazolato) Nickel(II) and its extraordinary thermal decomposition”, Asian Journal of Chemistry, vol. 25, pp. 7669-7674, 2013.[Abstract]

{Six coordinated axially bridged heteroleptic polymeric and monomeric Lewis base adducts from coordinatively unsaturated bis-(2-mercaptobenzothiazolato) nickel(II) {Ni(mbt)2, [NiC14H8N 2S4]} have been synthesized and charecterized by elemental analysis, spectral techniques, magnetic susceptibility measurements and thermal analysis using coordination sphere expansion method. These adducts have general molecular formula [Ni(mbt)2L]n for polymeric adducts and [Ni(mbt)2L2] for monomeric adducts, where L = pyrazine, 4,4′-bipyridine and 4,4′-azopyridine

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2013

Journal Article

S. L. Linguito, X. Zhang, Prof. M. Padmanabhan, A.V. Biradar, Jing I. Li, T. Xu, T.J. Emge, and T Asefa, “New polyoxomolybdate compounds synthesized in situ using ionic liquid 1-butyl-3-methyl-imidazolium tetrafluoroborate as green solvent”, New Journal of Chemistry, vol. 37, pp. 2894-2901, 2013.[Abstract]

Herein we report the facile, green syntheses of three new polyoxomolybdate-based inorganic-organic hybrid materials using room temperature ionic liquid (RTIL), 1-butyl-3-methyl-imidazolium tetrafluoroborate (bmim)[BF4], as a green and reactive solvent. The organic imidazolium component of the RTIL was incorporated into all three structures, the μ5-oxo octamolybdate cluster compound (bmim)3NH 4[Mo8O26] (1) and two Keggin-type cluster compounds, one being a charge transfer salt (bmim)4[PMo VMo11O40] (2) and the other having the unreduced anion (bmim)3[PMo12O40] (3). Phase pure and highly crystalline samples were obtained. In 1 the Mo8O 26 moiety is a tetranionic cluster in its β phase. Compound 1 contains three bmim cations and an NH4 + molecule to complement the -4 charge on the octamolybdate anion. The α-phase Keggin-type anion in 2, [PMoVMo11O40] 4-, contains one Mo atom in the +5 oxidation state, indicating that 2 is a charge transfer complex. The α-phase Keggin-type anion in 3, [PMo12O40]3-, has 12 fully-oxidized Mo atoms. Compound 3 has a band gap ∼3.5 eV. The catalytic nature of compound 3 in the oxidation of styrene to benzaldehyde was investigated. The maximum styrene conversion was 83%, while the maximum selectivity to benzaldehyde was 96.5%. The catalyst was successfully used for five cycles without significant loss in activity or selectivity. The structure of the catalyst remains unchanged after repeated use. Our work points to the feasibility of generating a wide variety of new and useful POM-based compounds through a 'green' synthesis route. © 2013 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

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2013

Journal Article

R. Nath, A.A. Tsirlin, P. Khuntia, O. Janson, T. Förster, Prof. M. Padmanabhan, Jing I. Li, Y. Skourski, M. Baenitz, Rosner, H., and Rousochatzakis, I., “Magnetization and spin dynamics of the spin S=12 hourglass nanomagnet Cu5(OH)2(NIPA)4·10H2O”, Physical Review B - Condensed Matter and Materials Physics, vol. 87, 2013.[Abstract]

We report a combined experimental and theoretical study of the spin S=12 nanomagnet Cu5(OH)2(NIPA)4·10H 2O (Cu5-NIPA). Using thermodynamic, electron spin resonance, and 1H nuclear magnetic resonance measurements on one hand, and ab initio density-functional band-structure calculations, exact diagonalizations, and a strong-coupling theory on the other, we derive a microscopic magnetic model of Cu5-NIPA and characterize the spin dynamics of this system. The elementary fivefold Cu2+ unit features an hourglass structure of two corner-sharing scalene triangles related by inversion symmetry. Our microscopic Heisenberg model comprises one ferromagnetic and two antiferromagnetic exchange couplings in each triangle, stabilizing a single spin S=12 doublet ground state (GS), with an exactly vanishing zero-field splitting (by Kramers' theorem), and a very large excitation gap of Δâ‰ 68 K. Thus, Cu5-NIPA is a good candidate for achieving long electronic spin relaxation (T1) and coherence (T2) times at low temperatures, in analogy to other nanomagnets with low-spin GS's. Of particular interest is the strongly inhomogeneous distribution of the GS magnetic moment over the five Cu2+ spins. This is a purely quantum-mechanical effect since, despite the nonfrustrated nature of the magnetic couplings, the GS is far from the classical collinear ferrimagnetic configuration. Finally, Cu5-NIPA is a rare example of a S=12 nanomagnet showing an enhancement in the nuclear spin-lattice relaxation rate 1/T1 at intermediate temperatures. © 2013 American Physical Society.

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2013

Journal Article

Peter Ash, Anju Bist, and Dr. Smitha Chandran S., “Moving towards Zero-Waste: A Case-Study from Kerala, India”, IEEE Global Humanitarian Technology Conference, South Asia Satellite Conference, Trivandrum, India, 2013.[Abstract]

The Amrita Institute of Medical Sciences is a 1450 - bed super-specialty hospital located in Kochi, Kerala, India. The hospital was founded by the world-renowned humanitarian and spiritual leader Amma, Sri Mata Amritanandamayi Devi, who envisioned an advancedcenter for serving the poor and suffering. Inspired by Amma’s vision of zero-waste, the hospital undertook its journey with a view to also reducing massive greenhouse gas emissions that result from improper handling of waste. Today, the hospital manages its municipal solid waste on an industrial scale, composting some eight metric tons of organic waste daily. This case study outlines the path followed to achieve zero-waste. Alongside, the rehabilitation of a former dump site is described in detail; at this very site are carried out all composting operations of AIMS More »»

2013

Journal Article

S. .A, “Nanocomposites from chlorobutyl rubber for advanced applications”, National Conference on Recent trends in Material Science & Technology , 2013.

2012

Journal Article

Dr. Saritha A., K. Joseph, S. Thomas, and R. Muraleekrishnan, “Chlorobutyl rubber nanocomposites as effective gas and VOC barrier materials”, Composites Part A: Applied Science and Manufacturing, vol. 43, pp. 864-870, 2012.[Abstract]

The field of polymer nanocomposites has attracted attention as a method of enhancing polymer properties and extending their utility by using molecular or nanoscale reinforcements rather than conventional particulate filled nanocomposites. These materials exhibit behavior different from conventional composite materials with micro scale structure due to small size of structural unit and high surface to volume ratio. Chlorobutyl rubber nanocomposites were prepared using organically modified cloisite 15 A and characterized using XRD and TEM. The gas barrier properties of the nanocomposites were modeled using the composite theories of permeation and the tortousity factors were predicted. Analysis of mechanical properties, transport and gas barrier properties of the nanocomposites as well as the calculation of break through times show the effectiveness of the material to be utilized as potential gas as well as VOC barrier materials. © 2012 Elsevier Ltd. All rights reserved.

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2012

Journal Article

M. S. Suresh and Prof. M. Padmanabhan, “Synthesis, thermal and spectral characterization of axially bridged polymeric and monomeric Lewis base adducts of bis (2-mercaptobenzothiazolato) cobalt (II)”, Rasayan Journal of Chemistry, vol. 5, pp. 311-320, 2012.[Abstract]

Octahedrally coordinated monomeric and axially bridged polymeric compounds from four coordinated cobalt(H) species have been synthesized and characterized by elemental analysis, infra red and electronic spectroscopy, magnetic susceptibility measurements and thermal analysis. The four coordinated system used was tetrahedral bis(2-mercaptobenzothiazolatocobalt(II), Co(mbt) 2 and ligands used were bidentate opposite end donors such as 4-aminopyridine, 4,4'-bipyridine and pyrazine. For comparison a monodentate ligand pyridine was also used. The complexes synthesized have the molecular formula [CoCmbt) 2L2] where L= pyridine and 4-aminopyridine and [Co(mbt)2L']n where L'= pyrazine and 4,4'-bipyridine. The infra red and thermal studies indicate that 4-aminopyridine is coordinated through its pyridyl nitrogen only, eventhough it is bidentate while others behave as bridging bidentate. These adducts have a trans octahedral structure which is preferable for extended linear framework, eventhough two isomeric forms are possible viz. cis and trans. The variation of magnetic moment on adduct formation was also carried out The thermal decomposition of Co(mbt)2 is seen taking place in two stages, in nitrogen atmosphere, with CoS, a stable residue. In the case of adducts an additional step was observed due to the loss Lewis bases used. The kinetic and mechanistic parameters were also evaluated from different decomposition stages. In most of the cases it follows Random nucleation, one nucleus on each particle obeying Mampel equation. © 2012 RASÄYAN. All rights reserved.

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2012

Journal Article

G. M.A and .Pillai, Z. S., “Synthesis and Antibacterial Screening of Novel derivatives of Embelin”, CRSI National Symposiium, 2012.

2012

Journal Article

S. .A and Kuruvilla Joseph, “chlorobutyl rubber for advanced applications”, In the national conference INCCOM-11 ISAMPE sponsored seminar, 2012.

2011

Journal Article

Akhil Sivan, A. Deepthi, and V. Nandialath, “Oxidative addition of 1,3-dicarbonyl compounds to terminal acetylenes mediated by cerium(IV) ammonium nitrate”, Synthesis, vol. 15, pp. 2466-2470, 2011.[Abstract]

Cerium(IV) ammonium nitrate mediated oxidative addition of 1,3-dicarbonyl compounds to terminal acetylenes to yield multisubstituted furan derivatives is reported here. The simplicity of the reaction and the ease of execution are particularly noteworthy.

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2007

Journal Article

K. Girish Kumar, Sareena John, Pearl Augustine, Remalakshmy Poduval, and Dr. Beena S., “A novel mebendazole selective membrane sensor and its application to pharmaceutical analysis”, 2007.[Abstract]

A PVC membrane sensor for the selective determination of mebendazole (MBZ) was fabricated. The sensor is based on an ion association of MBZ with silicotungstic acid (STA) as ion pair and bis(2-ethylhexyl)phthalate (BEP) as the plasticizing agent in a PVC matrix. The sensor showed a linear response for MBZ for a concentration range 1.0x10(-6)-5.0x10(-2) M with a Nernstian slope of 55.8 mV/decade (limit of detection 6.3x10(-7) M) in the pH range 4-7. It has a fast response time of <30 s. The sensor showed a very good selectivity for MBZ with respect to a large number of ions. The direct determination of MBZ in pharmaceutical formulations gave results that compare well with the data obtained from the standard method. More »»

### Publication Type: Book

Year of Publication Publication Type Title

2021

Book

Joseph Kuruvilla, Oksman, K., Gejo, G., Wilson, R., and Dr. Saritha A., Fibre Reinforced Composites: Constituents, Compatibility, Perspectives, and Applications. 2021.[Abstract]

Polymer-based fibre-reinforced composites FRC’s have now come out as a major class of structural materials being used or regarded as substituent’s for metals in several critical components in space, automotive and other industries (marine, and sports goods) owing to their low density, strength-weight ratio, and fatigue strength. FRC’s have several commercial as well as industrial applications ranging from aircraft, space, automotive, sporting goods, marine, and infrastructure. The above-mentioned applications of FRC’s clearly reveal that FRC’s have the potential to be used in a broad range of different engineering fields with the added advantages of low density, and resistance to corrosion compared to conventional metallic and ceramic composites. However, for scientists/researchers/R&D’s to fabricate FRC’s with such potential there should be careful and precise design followed by suitable process development based on properties like mechanical, physical, and thermal that are unique to each application. Hence the last few decades have witnessed considerable research on fibre reinforced composites.

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### Publication Type: Book Chapter

Year of Publication Publication Type Title

2021

Book Chapter

J. S. Jayan, Sethulekshmi, A. S., Gopika Venu, Dr. Saritha A., and Kuruvilla Joseph, “20 - Sustainable nanotextiles: emerging antibacterial fabrics”, in Antimicrobial Textiles from Natural Resources, M. Ibrahim H. Mondal, Ed. Woodhead Publishing, 2021, pp. 619-651.[Abstract]

The development of sustainable nanotextiles has transfigured the textile industry. Materials having functional applications like protection, antimicrobial activity and medicinal care can be achieved by manipulating the textiles into the nanoregime as well as by incorporating nanobased materials. The incorporation of suitable nanoparticles into fabrics enhances the antimicrobial activity of clothes, leading to a broad range of biomedical applications. The increased surface area of nanomaterials results in the enhanced absorption of light, which results in the degradation of organic matter. Nanotextiles have various other properties like superhydrophobicity, self-cleaning, sensing, odour reduction etc. This chapter tries to bring to light the antibacterial application of nanotextiles giving due importance to the fabrication techniques and their characteristic properties.

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2021

Book Chapter

S. Fathima, Deeraj, B. D. S., Appukuttan, S., and Kuruvilla Joseph, “Carbon fiber and glass fiber reinforced elastomeric composites”, in Fiber Reinforced Composites, Kuruvilla Joseph, Oksman, K., George, G., Wilson, R., and Dr. Saritha A., Eds. Woodhead Publishing, 2021, pp. 307-340.[Abstract]

Fiber reinforced materials were a quintessential ingredient in the manufacturing arena of humans since Stone Age. By dispersing the reinforcing fiber in a suitable matrix, novel functional materials could be developed. Carbon fibers and glass fibers are considered as important class of reinforcing fibers in polymer matrices owing to their high strength. Carbon fiber is five times stronger and two times stiffer than steel. Moreover, being a light weight material it is an ideal candidate for many high-end applications. Glass fiber has comparatively less stiffness than other reinforcing fibers, but it possesses the distinct advantage of having high specific strength and is cost effective. Glass fiber is a promising material to be used as a major reinforcement fiber because of its availability and ease of use. Elastomeric polymers are extensively used as matrices in polymer composites, because of their outstanding visco-elastic properties, flexibility and wide choice of fillers. This chapter gives an overview of the evolution, synthesis, mechanical, thermal and visco elastic characteristics of carbon fiber and glass fiber reinforced elastomeric composites coupled with their potential applications.

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2021

Book Chapter

J. S. Jayan, Appukuttan, S., Wilson, R., Kuruvilla Joseph, George, G., and Oksman, K., “An introduction to fiber reinforced composite materials”, in Fiber Reinforced Composites, Kuruvilla Joseph, Oksman, K., George, G., Wilson, R., and Dr. Saritha A., Eds. Woodhead Publishing, 2021, pp. 1-24.[Abstract]

The present century has witnessed composite materials to be the most promising and shrewd material for a variety of applications. Among them fiber (natural or synthetic) reinforced composites (FRCs) have gained significant interest owing to the high demand for lightweight materials with high strength for specific applications. The advantages of FRCs include high strength to weight ratio, high durability and stiffness, good damping behavior, flexural strength and most importantly good resistance to corrosion, wear, impact and fire (depending on the matrix and fiber reinforcement). The presence of such wide array of properties for FRCs have led to them being used extensively in a number of applications including mechanical, aerospace, automotive, marine, sports, biomedical, construction etc. The past decades have visualized exciting research in the area of FRC's which helped to unveil the properties of these exciting materials further and consign them in appropriate applications. These FRCs have shown outstanding performance in different fields of applications and hence have been promoted by researchers as promising alternatives to solitary metals and alloys. The global demand for fiber reinforced composites is expected to grow at a faster pace with the aerospace industry occupying the top position in the years to come. Major driving factors for the rising demand is none other than the high strength to weight ratio, corrosion resistance, energy absorption on impact, moisture and chemical resistance possessed by these materials. This chapter gives a general overview on the characteristics and processing of FRC's that are systematically outlined in this book.

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2021

Book Chapter

B. D. S. Deeraj, Jayan, J. S., Dr. Saritha A., and Kuruvilla Joseph, “Electrospun biopolymer-based hybrid composites”, in Hybrid Natural Fiber Composites, A. Khan, Rangappa, S. Mavinkere, Siengchin, S., Jawaid, M., and Asiri, A. M., Eds. Woodhead Publishing, 2021, pp. 225-252.[Abstract]

Nanofibers prepared from electrospinning technique has proved their efficiency and effectiveness in a wide spectrum of applications including filtration, biomedical field, energy storage, and conversion protective coating, EMI shielding, etc., Especially, electrospun fibers from biopolymers are value-added materials as their source is from nature or they degrade without causing hazardous situation to the environment. The high surface area, high aspect ratio, and surface functionalization make these nanofibers remarkable among others. This chapter describes electrospinning and discusses the properties and performance of biopolymer nanofibers and their composites fabricated through the electrospinning technique. The chapter deals with a general description of few polymers like cellulose, lignin, polycaprolactone (PCL), polylactide (PLA) together with a few applications in biomedical, mechanical reinforcement, etc.

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2021

Book Chapter

Dr. Saritha A., Deeraj, B. D. S., Jayan, J. S., and Joseph, K., “Rheology of Bioepoxy Polymers, Their Blends, and Composites”, in Bio‐Based Epoxy Polymers, Blends and Composites, John Wiley & Sons, Ltd, 2021, pp. 167-195.[Abstract]

Summary Bio-epoxy resins are considered as a green alternative for hazardous commercial epoxy resins derived mostly by the condensation of bisphenols and epichlorohydrin. Being a renewable source and environmental friendly material, these bio-epoxies are interesting material combinations for investigation. Bio-based thermosetting resins are getting wider attention, and the synthesis and utilization of these bio-resins are challenging and peculiar. In this chapter, a brief introduction of different types of bio-epoxies such as natural oil-based, phenolic-based, natural rubber-based, lignin-based, etc., are discussed. More focus is given to the rheological properties of the bio-based epoxies owing to its significance in manufacturing. A separate section for rheology of bio-epoxy-based composites and blends is presented, where different works of researchers are mentioned in a comprehensive way.

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2021

Book Chapter

J. S. Jayan, Deeraj, B. D. S., Dr. Saritha A., and Kuruvilla Joseph, “Biopolymer-derived carbonaceous composites and their potential applications”, in Hybrid Natural Fiber Composites, A. Khan, Rangappa, S. Mavinkere, Siengchin, S., Jawaid, M., and Asiri, A. M., Eds. Woodhead Publishing, 2021, pp. 253-280.[Abstract]

Biopolymers are potential polymeric biomolecules having potential applications in various fields of industry due to the properties of biocompatibility, biodegradability, and renewability. Considering the energy crisis coupled with waste minimization and management that is prevalent in our planet, the utilization of naturally occurring polymers in various high-end applications would be praiseworthy. The surface area and porosity of carbonaceous materials developed from biopolymers and the environmentally friendly nature of biopolymers have made it a vital component in sensing and super capacitance applications. This chapter tries to explore the various carbonization techniques of biopolymers that are prevalent in the synthesis of biopolymer-based carbonaceous composites. Applications of carbonaceous biopolymer composites are also explained in detail with special emphasis on energy storage and sensing applications. The emerging application of these composites as electromagnetic interference (EMI) shielding materials is also discussed.

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2020

Book Chapter

S. A. and Dr. Beena S., “An exhaustive study on the recent developments in the voltammetric sensors for the β- blocker propranolol hydrochloride”, in Biomedical Engineering Applications for People with Disabilities and Elderly in a New Covid-19 Pandemic and Beyond (Elsevier), 2020.

2020

Book Chapter

S. A. and Dr. Beena S., “Carbon based electrodes as a Scaffold for the electrochemical sensing of pharmaceuticals: A special case of immunosuppressant drugs”, in Electronic Devices, Circuits, and Systems for Biomedical Applications (Elsevier), 2020.

2020

Book Chapter

J. S. Jayan, A.S, S., Venu, G., Dr. Saritha A., and Joseph, K., “Synthesis, Designing and Challenges of Functionalized Polymeric Nanomaterials and Their Spectroscopic Applications”, in Nanomaterials for Spectroscopic Applications , enny Stanford Publishing Pte. Ltd., 2020, pp. 137-159.[Abstract]

Polymeric nanoparticles are sub-micron level colloidal particles in the form of nanospheres or nanocapsules. These nanoparticles can be formed by either modifying nanoparticles using a polymer or by the sequential arrangement of long polymeric chains in the form of micro or nanostructures. Dendrimers, block copolymers, peptides, etc. can be arranged in such a way as to get welldefined nanostructures and can also be used for the modification nanoparticles. These polymeric nanomaterials have wide applications in the field of drug delivery, bioimaging, storage, photocatalysis, biosensing, chemosensing, semiconduction, water purification, composite fabrication, etc. This chapter tries to bring to light the various fabrication and characterization methods of polymeric nanoparticles. Applications of these polymeric nanoparticles are also discussed in detail with special emphasis on spectroscopic investigations.

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2020

Book Chapter

Dr. Saritha A., Thomas, B., George, G., Wilson, R., and Kuruvilla Joseph, “Chapter 8 - Elastomer-based materials for EMI shielding applications”, in Materials for Potential EMI Shielding Applications, Kuruvilla Joseph, Wilson, R., and George, G., Eds. Elsevier, 2020, pp. 121-143.[Abstract]

Electromagnetic shielding is presently considered very crucial for various electrical systems owing to the creation of electromagnetic pollution instigated by the alarming usage of electronic gadgets working at diverse frequencies and power levels. Conventionally used electromagnetic interference (EMI) metallic shields lack flexibility and hence cannot be considered as the right candidates for certain applications. This problem requires immediate attention because it causes drastic effects on the lifetime and performance of electronic devices and has an adverse effect on human beings as well. Rubber-based composite materials are regarded as suitable candidates for the fabrication of electromagnetic shields due to their combined electrical conductivity, interesting mechanical, and dielectric properties, elasticity to cover curved structures, and weather resistance for outdoor applications. This chapter aims to discuss the various fillers as well as elastomers used in the fabrication of elastomeric composites used in the preparation of EMI shielding devices. Finally a discussion of elastomeric blends used for shielding purpose will also be added.

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2020

Book Chapter

M. S. Mathew, Dr. Saritha A., and Joseph, K., “Biosensor and Drug Delivery Application by the Utilization of Green Nanotechnology”, in Green Nanomaterials Sustainable Technologies and Applications, pple Academic Press, 2020.[Abstract]

Green nanotechnology enables the synthesis and development of nanomaterials through safer fabrication routes with low toxicity so that the utilization of these materials in biomedical applications is constantly gaining momentum. The advent of green initiatives in nanotechnology has revolutionised the biosensor and drug delivery arena and biosensors are now considered as powerful analytical tools for selective and sensitive detection and examination of many analytes as well as diseases. Apart from nanomaterials, nanoclusters, hybrid nanomaterials, biological molecules, microbes and nanocomposites are also involved in the active fabrication of biosensors and drug delivery agents. This chapter focuses on the various green strategies used for the fabrication of potential nano clusters that could be employed in the fields of bio detection and drug delivery. Though there are many review articles that point out the utility of nanomaterials in biosensing and drug delivery, yet a few reports concentrate exclusively on nanoclusters. Hence our earnest approach is to bridge the gap in literature. The chapter also concentrates on the various mechanisms through which these biosensors and drug delivery agents operate.

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2019

Book Chapter

J. S. Jayan, Jayadev, D., Pillai, Z., Joseph, K., and Dr. Saritha A., “The stability of the super hydrophobic surfaces”, in Superhydrophobic polymer coatings, Elsevier, 2019.

2019

Book Chapter

D. Jayadev, Jayan, J. S., Pillai, Z. S., Kuruvilla Joseph, and Dr. Saritha A., “Characterization of superhydrophobic polymer coating”, in Superhydrophobic Polymer Coatings, S. K. Samal, Mohanty, S., and Nayak, S. Kumar, Eds. Elsevier, 2019, pp. 91-121.[Abstract]

Superhydrophobic surfaces have aroused immense interest in scientific community and have emerged as a hottest area of research recently. Due to the extensive assortment of prospective applications of superhydrophobic surfaces, there is a necessity for a deeper comprehension of the morphology, roughness, surface chemistry, surface wetting, and stability. Characterization of the wetting properties is a major criterion required for the targeted development of superhydrophobic materials. The fabrication of such materials should satisfy two major conditions. First, the surface has to be of low energy and second, the nano and the microstructures need to be designed in such a way that it leads to the entrapment of air. Hence, understanding whether the prepared material meets the end application requirement of hydrophobicity, characterization, and quantification of the material properties are of utmost importance. This article attempts to explain the important characterization methods used to quantify wetting properties of superhydrophic layers such as contact angle measurement, roll-off angle measurement, scanning electron microscopy (SEM), atomic force microscopy, white light interferometry, etc. The chapter will also describe details of each method in terms of principle, instrumentation, and interpretation of test results.

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2016

Book Chapter

K. Y. Sandhya, Dr. Saritha A., and Kuruvilla Joseph, “Liquid Crystalline Polymers from Renewable Resources: Synthesis and Properties”, in Liquid Crystalline Polymers: Volume 1–Structure and Chemistry, Cham: Springer International Publishing, 2016, pp. 273–306.[Abstract]

Materials from renewable sources are attracting immense attention due to the excellent properties and ecological advantages it can offer and due to the growing environmental concerns. Liquid crystalline polymers (LCP) from renewable sources have engrossed considerable attention during the past few decades. Nowadays, agro based renewable materials are the subject of a growing number of academic and industrial research projects, because of diminishing fossil resources combined with the increasing environmental concern of petroleum based polymers. Renewable resources such as cellulose, vegetable oils and other plant and animal originated products are ideal alternatives to provide base chemicals for various materials, as they are abundant throughout the world and contain several reactive chemical sites such as double bonds, allylic carbons, ester groups, and the alpha carbons of the ester groups, which can be used for polymerization. LCPs can be successfully synthesized from a good number of natural sources including cardanol, castor oil and can be derived from biopolymers such as cellulose, DNA, proteins etc. The study of liquid crystal phases of cellulosic esters and ethers become attractive owing to their properties such as toughness and processability. Cardanol obtained from cashew nut shell liquid possesses functional groups for creating polymers and has interesting structure for exhibiting liquid crystalline properties. Cardanol based LCP can form cross linked network polymers due to the unsaturation of side chains and possibly can freeze the liquid crystalline phase. On the other hand liquid crystal properties of cellulose in electro optical applications open new horizons for these traditional materials. A milestone in the development of nano cellulose science and technology is the discovery of cellulose nano crystals (CNC) from natural cellulose sources. CNC is made from cellulose which is a natural polymer of wide abundance and is an almost non-exhausting source. These nanofibrils under particular concentration can form ordered structures leading to lyotropic liquid crystals. It was noticed that rod like CNC can form a stable chiral nematic liquid crystalline phase. The chiral nematic (cholesteric) phase thus formed is characterized by long-range orientational order of the nanorods combined with a helical modulation of the direction in which they align. The intriguing ability of CNCs to self-organize into a cholesteric liquid crystal phase with a helical arrangement has attracted significant interest, as this arrangement gives dried CNC films a photonic band gap. Thus formed film has attractive optical properties, creating possibilities for use in applications such as security papers and mirrorless lasing. Controlling and understanding the mechanisms of liquid crystalline self-assembly of LCPs are not only of fundamental importance but are steps along the route to produce novel materials with desirable optical or mechanical properties. Nanostructured films with a photonic band gap phase of CNC suspensions arising from the spontaneous helix formation in the cholesteric liquid crystal have been the focus of several studies. The use of CNC suspension as a self-assembled template for the synthesis of inorganic materials offers a promising and versatile platform to fabricate multifunctional mesoporous materials with photonic crystal properties of very large surface areas. The combination of CNC and inorganic materials with higher refractive indices may lead towards photonic devices such as tunable mirrorless lasers, and CNC-templated materials with specific surface functionalities may pave way for the development of enantioselective sensors.

In the proposed chapter we would discuss the different methods of synthesis of LCPs using renewable sources like cellulose, cardanol etc., chemical functionalization and characterization of cellulose, nano cellulose and their derivatives and their subsequent self organization into LCPs. The structural as well as phase transitions will be discussed in detail with various characterization techniques. A brief overview on the future scope of research and applications in the aforementioned field will also be given.

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2013

Book Chapter

Dr. Saritha A., S. K. Malhotra, S. Thomas, K. Joseph, K Goda, and M. S Sreekala, “State of the Art – Nanomechanics”, in Polymer Composites, vol. 11, Wiley-VCH Verlag GmbH & Co. KGaA, 2013, pp. 1–12.[Abstract]

This chapter contains sections titled: * Introduction * Nanoplatelet-Reinforced Composites * Exfoliation–Adsorption * In Situ Intercalative Polymerization Method * Melt Intercalation * Nanofiber-Reinforced Composites * Characterization of Polymer Nanocomposites * Recent Advances in Polymer Nanocomposites * Future Outlook * References

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2013

Book Chapter

Dr. Saritha A. and Kuruvilla Joseph, “Barrier Properties of Nanocomposites”, in Polymer Composites, Wiley-VCH Verlag GmbH & Co. KGaA, 2013, pp. 185–200.[Abstract]

This chapter contains sections titled: * Introduction * Nanocomposites from Ceramic Oxides * Nanocomposites from Nanotubes * Layered Silicate Nanocomposites * Composite Models of Permeation * Techniques Used to Study the Permeability of Polymers and Nanocomposites * Calculation of Breakthrough Time * Applications * Conclusions * References More »»

2012

Book Chapter

Dr. Zeena S. Pillai and Beena Joy, “Chemoprofiling and Antioxidant Activity Studies of Shilajit – A Herbal Composition”, in Utilisation and management of Medicinal Plants, vol. 2, New Delhi: Daya Publication House, 2012, pp. 273-287.

### Publication Type: Conference Paper

Year of Publication Publication Type Title

2020

Conference Paper

R. G. Krishnan, Dr. Beena S., S., G., P., V., Aravind, A., and G., G. M., “Enhanced Electrocatalytic Activity of Poly (trans- 2,3-Dimethyacrylic acid) Modified Electrode for Hydrazine Sensing (Book Series)”, in Accepted in Lecture notes in mechanical engineering; Springer Book Series , 2020.

2018

Conference Paper

Nayana Krishna, Nanda Kumar G, Neethu T S, Rini John, Sudheesh. R. Babu, and Dr. Smitha Chandran S., “One Pot Green Synthesis of Silver Nanoparticles with Multiple Applications”, in 7th International Conference on Material Processing and Characterization, Gokaraju Rangaraju Institute Of Engineering & Technology,Bachupally, Hyderabad,Telangana , 2018, vol. 5, pp. 20567 - 20571.

2018

Conference Paper

Jitha S Jayan, Dr. Saritha A., Sreepriya R, and Kuruvilla Joseph, “Transport phenomena of graphene oxide modified epoxy nanocomposites using diaminodiphenyl methane as curing agent”, in 2017 IEEE International Conference on Technological Advancements in Power and Energy ( TAP Energy), Kollam, India, 2018.[Abstract]

Epoxy resins are employed a coating materials in aircraft as well as marine applications owing to its outstanding mechanical and chemical resistance. Epoxy composites are also effective in constructing body parts of aircraft and marine vehicles. But due to degradation by water, epoxy nanocomposites have less durability. Hence to enhance the water repelling ability or decrease the uptake of water of epoxy composites it is advisable to incorporate nanofillers. Graphene is an excellent nanofiller for toughening epoxy due to its mechanical, thermal and electrical properties and hence it is a very adaptable filler to improve many properties of epoxy like mechanical, thermal and electrical properties. Present work focuses on the enhancement of barrier properties especially on moisture resistance of epoxy graphene oxide nanocomposites after curing using Diaminodiphenyl methane. In this specific study moisture uptake of epoxy and epoxy nanocomposites having different compositions were analyzed at different temperature ranges like room temperature 30, 50°C and 70°C taking water as a solvent for a time period of 15 days.

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2018

Conference Paper

Subramanian L, Leema M, Pradeep N S, Joy B, and Dr. Zeena S. Pillai, “Synthesis and Antibacterial Screening of Novel Derivatives of Embelin”, in International Conference on Advances in Materials and Manufacturing Applications 2017 IConAMMA 2017 - IOP Conference Series: Materials Science and Engineering, 2018, 1st ed., vol. 310.[Abstract]

Embelin, a naturally occurring compound extracted from Embelia ribes is used in Ayurvedic system of medicine owing to its wide spectrum of biological activities. In the present work, we have aimed at improving the efficacy of Embelin by appropriate structural modifications. A few novel derivatives of Embelin have been prepared. The antibacterial screening of these derivatives were carried out and compared with a well known antibiotic, Streptomycin. The derivatives exhibited better activity than Streptomycin and the lead molecule, Embelin.

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2017

Conference Paper

P. Varun and Dr. Smitha Chandran S., “Sustainable utilization of some noxious aquatic weeds by energy recovery using high solid anaerobic digesters”, in International Conference on Technological Advancements in Power and Energy ( TAP Energy), EEE Department at Amritapuri Campus, Amritapuri, Kollam, 2017.[Abstract]

One of the options on which we zeroed in was utilization of weeds for generating energy as biogas via anaerobic digestion. This study makes an attempt to utilize some noxious aquatic weeds as a feedstock in High Solid Anaerobic Digesters (HSADs) for the recovery of energy. The specific objectives of the study were to fabricate lab scale HSADs for the digestion of organic fraction of some common noxious aquatic weeds and to evaluate the suitability of it as a feed stock in Anaerobic Digesters and the recovery of energy in terms of biogas. The findings indicate 4.873% of dry solids loss and 96.32% degradation of volatile solids at the end of the experiment for Typha latifolia with a total biogas yield of 14,175 ml and resulted into a total of 83,609 m3/m3digester volume and 4.168% of dry solids loss and 92.46% degradation of volatile solids at the end of the experiment for Pistia stratiotes with a cumulative biogas yield of 17,570 ml and resulted into a total of 83,609 m3/m3in 30 days. The performance of the reactors is similar with the values reported in earlier works. This waste utilization forms a sustainable solution for the management of organic fraction of municipal solid waste. Also the slurry from the bioreactor can be utilized as a bio fertilizer.

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2017

Conference Paper

Dr. Beena S., A Santhy, R Vidya, P Uma Sankar, and Rejithamol, R., “Clopidogrel-tetralodo mercurate ion association immobilized PVC membrane sensor for the determination of clopidogrel in pharmaceutical formulations”, in 2017 International Conference on Technological Advancements in Power and Energy (TAP Energy), Kollam, India, 2017.[Abstract]

Fabrication of the PVC membrane sensor incorporating clopidogrel-tetraido mercurate as an electro active material for the determination of clopidogrel bisulphate is demonstrated. Sensor matrix having a composition of PVC 32%, ion association 2.5% and Di-n-butyl phthalate 56.5 % showed best nernstian behavior in the concentration range 1×10 -2 -1×10 -7 M with a lower detection limit of 2.9 × 10 -8 M. Working pH range and response time was found to be 1.8-4.0 and 5s respectively. The sensor was fruitfully utilized for the quantification of clopidogrel from Clopilet tablets. Comparative studies on the various parameters that depend on the performance characteristics of the present sensor with that of the literature reports were also included.

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2015

Conference Paper

Bindu P. Nair, T.K. Manojkumar, Dr. Sreedhar K. M., A.V. Mohamed, and Z. Hukuman, “Pyranone Benzene complexes as potential nano-flippers: A DFT study”, in 2015 International Conference on Advances in Computing, Communications and Informatics, ICACCI 2015, 2015, pp. 335-338.[Abstract]

Computational studies were carried out on Pyranone Benzene clusters at different charged states using density functional theory. The relative orientation of the two molecules depends on the charged state of the complex and this property can be utilized in designing nano-mechanical devices such as flippers or switches. © 2015 IEEE.

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2014

Conference Paper

Peter Ash, Anju Bist, and Dr. Smitha Chandran S., “Habitat Restoration: A case study from Kochi, Kerala, India”, in International Conference on Waste Management for Sustainable development (ICWMSD-2014), Department of Civil Engineering, NSS Engineering College, Palakkad, 2014.

2014

Conference Paper

Anjali, Shilpa Purushothaman, and Dr. Smitha Chandran S., “An Ecofriendly option for Management of Waste Water- A Case study from Amrita, Kerala, India ”, in National Seminar on Contemporary Techniques in Environmental Research and Conservation (CTERC-2014) , P G Department of Environmental Sciences, All Saints’ College, Thiruvananthapuram , 2014.

2014

Conference Paper

Aparna Guleria, Smitha Asok V., and Dr. Smitha Chandran S., “Hydrological studies of a small watershed area of Karamana River basin using GIS”, in National Seminar on Contemporary Techniques in Environmental Research and Conservation (CTERC-2014), P G Department of Environmental Sciences, All Saints’ College, Thiruvananthapuram, 2014.

2014

Conference Paper

, K.K, V., and Pillai, D. Zeena S., “Photo induced morphological changes of silver nanoparticles”, in National Seminar on Current Trends in Chemistry CTriC 2014, 2014.

2014

Conference Paper

Dr. Saritha A., Rincy Sebastian, and Shilpa K., “Synergistic effect of CNT and Nanoclay on the properties of chlorobutyl rubber nanocomposites”, in National Conference on material science and Technology held at Indian Institute of Space Science and Technology,, Trivandrum , 2014.

2014

Conference Paper

S. T, R, A. A., and Sambhudevan, S., “Effect of co-precipitated nickel ferrite on the mechanical and magnetic properties of natural rubber-ferrite composites”, in Effect of co-precipitated nickel ferrite on the mechanical and magnetic properties of natural rubber-ferrite composites at National conference on material science and technology,, Thiruvananthapuram, 2014.

2013

Conference Paper

Dr. Smitha Chandran S. and Smitha Asok, “Utlilization of Limnocharisflava, an invasive exotic aquatic weed from Kuttanad wetland ecosystem as a potential feedstock for aquaculture”, in International Seminar on Advances in Aquaculture Technologies (ISATT-2013), Department of Zoology, All Saints College Thiruvananthapuram, 2013, pp. 53-55.

2013

Conference Paper

Peter Ash, Anju Bist, Dr. Smitha Chandran S., Dan Sullivan, and Nikhil Korthurkar, “Rehabilitating former landfill sites: A case study in habitat restoration”, in IEEE Global Humanitarian Technical Conference (GHTC 2013), San Jose, California USA , 2013.[Abstract]

This paper describes the dramatic success in the eco-restoration of a heavy-metal contaminated open garbage dump. A number of heavy metals (As, Cd, Cu, Co, Pb, Hg, Cr) were detected in the soil and river sediment at the site. The main restoration activities included mulching, surface-addition of compost and fresh soil and phytoremediation using vetiver and other plants. Within three years of the restoration activities, heavy metal concentrations in the contaminated soil reduced drastically. There was relatively low uptake of the heavy metals by the plants; however, they might have been crucially responsible for providing a favorable environment for soil-restoring microrganisms in their rhizosphere. Observable habitat-restoration continues at the site, including the return of birds and insects and other wildlife, making this an ideal site for further research and demonstration for community awareness and education.

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2013

Conference Paper

S. Sambhudevan and , “Rubber composites with enhanced EMI Sheilding”, in Conference on Recent trends in Material Science & Technology, IIST Thiruvananthapuram, 2013.

2013

Conference Paper

S. Sambhudevan and , “X-Ray Shielding performance of modified Gadolinium oxide based natural rubber composites”, in International Conference on Emerging Trends in Chemical Sciences VIT University, Vellore Tamil Nadu, 2013.

2012

Conference Paper

B. S and Girish Kumar, “Fabrication of PVC membrane sensor for Gadolinium”, in National conference organized by KONGU, 2012.

2012

Conference Paper

A. K.M. and Chandran, S., “Variation in Air Pollution Tolerance Index of some common plants near The Kerala Minerals”, in National Conference on Recent Trends in Chemistry organized by Department of Chemistry, Chavara, Kollam, 2012.

2012

Conference Paper

, M.A, G., and Beena Joy, “Synthesis and Antibacterial Screening of novel derivatives of 2,5-dihydroxy-3-undecyl1-1,4-benzoquinone”, in National Conference sponsored by DST & BRNS, Kongu Engineering College, Erode , 2012.

2012

Conference Paper

S. .A, Kuruvilla Joseph, and Sabu Thomas, “Dielectric properties of chlorobutyl rubber nanocomposites”, in International conference on Natural Polymers, MG University, Kottayam, 2012.

2011

Conference Paper

Dr. Krishnashree Achuthan, Sreelatha K. Sharma, S. Surendran, Dr. Shyam Diwakar, Prof. Prema Nedungadi, S. Humphreys, Dr. Sreekala C. O., Dr. Zeena S. Pillai, Raghu Raman, A. Deepthi, Rathish Gangadharan, Dr. Saritha A., Jyothi Ranganatha, Sreedha Sambhudevan, and Suma Mahesh, “The VALUE @ Amrita Virtual Labs Project: Using Web Technology to Provide Virtual Laboratory Access to Students”, in Global Humanitarian Technology Conference (GHTC), 2011 IEEE, 2011, pp. 117-121.[Abstract]

In response to the Indian Ministry of Human Resource Development (MHRD) National Mission on Education through Information and Communication Technology (NME-ICT) Initiative, the Virtual and Accessible Laboratories Universalizing Education (VALUE @ Amrita) Virtual Labs Project was initiated to provide laboratory-learning experiences to college and university students across India who may not have access to adequate laboratory facilities or equipment. These virtual laboratories require only a broadband Internet connection and standard web browser. Amrita Vishwa Vidyapeetham University is part of a consortium of twelve institutions building over two hundred virtual labs covering nine key disciplines in science and engineering. This National Mission project hopes to reach out to India's millions of engineering and science students at both undergraduate and postgraduate levels. The Virtual Labs Project is providing virtual laboratory experiments that directly support the All India Council for Technical Education (AICTE) and the University Grants Commission (UGC) model curricula for engineering and sciences undergraduate and postgraduate programs.

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### Publication Type: Conference Proceedings

Year of Publication Publication Type Title

2017

Conference Proceedings

Sreedha Sambhudevan and B. Shankar, “Development of Medical Imaging X-ray Shielding Materials based on Natural Rubber/Nano Composites-thermal Degradation Studies”, 2017 International Conference on Intelligent Sustainable Systems (ICISS). 2017.[Abstract]

This paper discusses the development of X-ray shielding materials based on rare earth oxide and natural rubber materials. Medical imaging, as we know is currently using highly toxic lead containing garment for protection from harmful radiations. Both technicians as well as patients are suffering from the ill effects of radiation exposure to a great extent. The current research presented in this paper can be an alternative to the above mentioned problems. Rare earth oxide was used as filler in natural rubber matrix to prepare eco-friendly composites. The samples were analyzed to confirm the particle size, even distribution in matrix phase, mechanical properties and their response to high temperature conditions

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2017

Conference Proceedings

Athira Krishnan, Bency Joseph, Krishna M Bhaskar, and S. M. A. Shibli, “Fabrication of PANI-TiO2 incorporated Ni-P electrode for alkaline water electrolysis”, 2017 IEEE International Conference on Technological Advancements in Power and Energy (TAP Energy ). IEEE, 2017.[Abstract]

Composite incorporated Ni-P electrodes were fabricated for alkaline water electrolysis. The effect of (Polyaniline) PANI-TiO2 polymer composite in hydrogen evolution efficiency of Ni-P electrode in NaOH medium was studied. Characterization of the composites was carried out by XRD and coating composition was confirmed by EDS analysis. Catalytic action of the fabricated electrodes was analysed by polarization and electrochemical impedance spectroscopic techniques. The optimized electrodes exhibited a lower overpotential value of 139 mV for hydrogen evolution reaction at 200 mA cm-2. The composite incorporated electrodes achieved enhanced catalytic activity as a result of improved active sites, increased surface roughness and decreased resistance for electron transfer reaction in comparison with pure Ni-P electrode.

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2014

Conference Proceedings

Lekshmi S Kumar, Soumya. M. Nair, and Dr. Smitha Chandran S., “Recovery Of Energy From Organic Fraction Of Municipal Solid Waste By High Solid Anaerobic Digestion”, The National Seminar on Contemporary Techniques in Environmental Research and Conservation (CTERC-2014) . P G Department of Environmental Sciences, All Saints’ College, Thiruvananthapuram , 2014.

2014

Conference Proceedings

Sreedha Sambhudevan, Balakrishna Shankar, Dr. Saritha A., and Kuruvilla Joseph, “Rare earth oxide filled natural rubber composites: Synthesis, characterization and x ray shielding”, International conference on advanced functional materials held at NIIST. Trivandrum , 2014.

2014

Conference Proceedings

Akhil Sivan, A. Deepthi, and K. S. Nair, “An Efficient Synthesis of Spiro Dihydrofuran Fluorenes Using CAN Supported on Silica”, National Seminar on Frontiers of Polymers and Advanced Materials. Dept. of Chemistry, University of Kerala, Trivandrum, Kerala, 2014.

2014

Conference Proceedings

Akhil Sivan and A. Deepthi, “A Direct Synthesis of Vicinal Triketones from β-Diketones: 1,3 to 1,2,3”, 16th CRSI National Symposium in Chemistry. IIT Bombay, Powai, Mumbai, 2014.

2013

Conference Proceedings

Lakshmi S. Kumar and Dr. Smitha Chandran S., “High Solid Anaerobic Digestion for the recovery of Energy from Organic Fraction of Municipal Solid waste”, The International Conference on Emerging Trends in Chemical Sciences . VIT University, Vellore TamilNadu, 2013.

2012

Conference Proceedings

S. Chandran and Arjun, K. M., “Changes in Air Pollution Tolerance Index of some common plants near The Kerala Minerals, and Metals Limited”, National Conference sponsored by DST & BRNS. Kongu Engineering college, 2012.

2012

Conference Proceedings

Akhil Sivan and A. Deepthi, “Reactivity of Ethyl-2,3-butadienoate in Cerium (IV) ammonium nitrate (CAN) mediated intermolecular C-C bond formation”, 14th CRSI National Symposium in Chemistry. NIIST, Trivandrum, Kerala, 2012.

2011

Conference Proceedings

Akhil Sivan, A. Deepthi, and Vidya, N., “Synthesis of Fused Furans by Oxidative Addition”, National Seminar on Current Trends in Chemistry, Dept. of Applied Chemistry. Cochin University of Science and Technology, Kerala, 2011.