Dr. Amrita Thakur

This article presents a novel non-destructive microwave technique for predicting fluoride contamination in pure water. The proposed microwave-based sensing technique uses an open-ended coaxial probe (OECP) microwave sensor for monitoring fluoride concentration in water. The sensor output is the input of Artificial Neural Network (ANN) for predicting the complex dielectric constant of contaminated water, which has direct correlation with fluoride contamination in water. The ANN is trained through analytically generated sensor output for various lossy liquid materials and tested for experimental data obtained through laboratory prepared samples. Hence, the proposed technique has the capability to compute the amount of fluoride contamination faster, when compared to analysis only method. The results shows that a well-trained ANN is computationally efficient and capable of predicting the amount of fluoride level in the pure water. The results also has good agreement with the data published in the literature at room temperature.

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Silver nanocomposite hydrogel (SNH) with biodegradable polymers, sodium alginate and sodium lignosulphonate was synthesized employing principles of green chemistry for possible application in the field of controlled drug release. One of the factor that determines the release of drug from blend is the quantity of drug present/trapped inside the polymer network. The entrapment of drug in the polymer matrix depends upon the stability of matrix and interaction between the drug and the matrix. In the present study effect of presence silver nanoparticles in the polymeric matrix on the Drug Entrapment Efficiency (DEE) for the drug ciprofloxacin (CPX) was investigated. The drug entrapment efficiency for CPX loaded beads of SA/LS was calculated for similar conditions, to evaluate the effect of silver nanoparticles. Experimental results confirmed role of crosslinking and presence of silver nanoparticles on the stability of SNH and its entrapment efficiency. Observations indicate that the drug entrapment is more for the SNH as compared to the blend. Presence of silver nanoparticles help stabilize the polymer matrix, improves binding inside the matrix, which leads to the better drug entrapment.

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Biodegradable polymer blends are prepared by mixing two natural biodegradable polymers Sodium alginate (SA) and Lignosulphonic acid (LS) by solution casting method for controlled drug delivery application. Successful application of blend for controlled drug delivery requires its stability under physiological condition. Thermal analysis (TGA) reveal thermal transitions, degradation processes and thermal stability’ of blends and gives an important insight about its stability’. In this paper TGA data has been used to evaluate degradation of SA/LS blends with temperature. The energy’ of activation for the thermal degradation of polymers and blends has been calculated by ‘Horowitz and Metzger' method. These studies reveal that blends are stable as compared to their polymers. © 2018, Iran University of Science and Technology. All rights reserved.

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ne pot synthesis of lignosulhonic acid (LS) based bionanocomposite material containing silver nanoparticle (AgNP) was achieved. LS acted as both reducing and stabilising agent in aqueous medium. Reaction variables such as reactant and stabilising agent concentration, temperature and time were optimised. Progress of reaction and characterisation of material was done by using advanced instrumentation techniques like UV-Vis spectroscopy, FTIR, XRD, and TEM. Nearly spherical and stable nanoparticles of average size 4-10 nm was achieved. Characteristic SPR band at 409 nm and TEM images indicated synthesis of mono dispersed and nearly spherical AgNP. XRD and SAED results confirmed polycrystalline AgNP with face centred cubic structure. Uniqueness of developed material is its insolubility and very high stability in water. It has also shown no release of AgNP in water.

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Presence of certain substances in air adversely affects human health, environment and climate. These chemicals are mainly added due to human activities. Maintaining air quality requires regular monitoring, identification of source of pollution and adoption of preventive measure. Bangalore a city in India has grown in size and population recently due to growth of IT industry. This rapid growth and related civic activity has affected its ecological services. The objective of this study is to identify air pollution trend in Bangalore and investigate the factors contributing towards it. Data for analysis has been obtained from state pollution control board website and has been used without any modification. Three criteria pollutants measured regularly and for longest period of time, sulphur dioxide (SO2), nitrogen dioxide (NO2) and respirable particulate matter (PM10) have been investigated for air quality analysis.

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Blends of sodium alginate (SA) and lignosulphonic acid (LS) has been prepared in the ratio of 80/20. The prepared blends were crosslinked using chlorides of calcium, barium, strontium and aluminum. The crosslinking of blends was done for different time intervals and then these blends were subjected for swelling studies in aqueous medium of pH 7.4. The observations indicate that the crosslinking is diffusion controlled and is affected by the size of metal ion and the type of alginate used. The improved swelling time for crosslinked blends in aqueous medium supports the fact that the stability under physiological conditions of the blends is improved due to crosslinking with the metal ions. Calcium chloride and barium chloride forms strong crosslink with the blend. Calcium ion crosslinked blends can be considered suitable for biomedical drug applications. The investigations on crosslinked blends using FTIR, SEM, XRD and EDAX are in close agreement with swelling results. © 2016 The Polymer Society of Korea. All rights reserved.

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Blends of sodium alginate (SA) and lignosulphonic acid (LS) has been prepared in the ratio of 80/20. The prepared blends were crosslinked using chlorides of calcium, barium, strontium and aluminum. The crosslinking of blends was done for different time intervals and then these blends were subjected for swelling studies in aqueous medium of pH 7.4. The observations indicate that the crosslinking is diffusion controlled and is affected by the size of metal ion and the type of alginate used. The improved swelling time for crosslinked blends in aqueous medium supports the fact that the stability under physiological conditions of the blends is improved due to crosslinking with the metal ions. Calcium chloride and barium chloride forms strong crosslink with the blend. Calcium ion crosslinked blends can be considered suitable for biomedical drug applications. The investigations on crosslinked blends using FTIR, SEM, XRD and EDAX are in close agreement with swelling results. More »»

<p>This study reports the preparation and spectroscopic evaluation of a series of transition metal complexes of Co(II), Ni(II), and Cu(II) with schiff base ligand 1-ethyl, 1, 2, 3, 5, tetrahydroimidazo (2, 1-b) quinazolin 5-one semicarbazone (ETQS). The ligand and its Co(II), Ni(II) and Cu(II) complexes were formulated by elemental analysis, molar mass, infrared spectra, electronic spectra, molar conductivity and magnetic susceptibility measurements. In the light of above studies it is proposed that the compound ETQS behaves a bidentate ligand and coordination takes place through azomethine nitrogen and carbonyl oxygen of semicarbazone moiety. The remaining positions of metal Ions are satisfied by negative ions such as Cl- , Br, l- and NO3- . The complexes were proposed octahedral geometry. All the synthesized ligand and complexes have been screened for antimicrobial activity.</p>

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The paper presents a novel non-invasive microwave technique for monitoring salt concentration in pure water. The technique is based on near field analysis of open ended coaxial probe (OECP) sensor with material under test (MUT) using plane wave spectrum theory. The proposed technique is compared with experimental results for various concentration of salt solution between 1GHz to 10GHz range. The computed result shows good agreement with experiment. The microwave technique shows better result at lower microwave frequency as compared to higher frequency. At 2GHz range the response of the technique and measurement shows a linear relationship with the salt concentration. The technique shows the potential of extracting the physical parameter, like permittivity, of the salty water.

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