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Parumala, India

Pillai S.S.,Moore Research | Girija N.,Db Pampa College | Williams G.P.,Bishop Moore College | Koshy M.,Moore Research
Chemistry and Ecology | Year: 2013

Chromium is a pollutant present in electroplating waste water and its removal is necessary for the protection of the environment. Vetiveria zizanioides (VZ) was grown in chromium effluent concentrations of 50, 100 and 200 mg kg -1 soil amended with organic manure and the potential for phytoremediation was determined. The amounts of Cr in plant tissues (root and shoot), soil and percentage electrolyte leakage of VZ roots were analysed. From the results, VZ amended with organic manure showed the greatest potential for Cr removal because of its faster growth and larger biomass achieved over the whole length of the experiment. In this study, 92.25% Cr removal efficiency was obtained with a Cr concentration of 50 mg kg -1 soil and removal efficiencies of 90.5% and 85% were obtained with 100 and 200 mg kg-1, respectively after a period of two months of VZ growth. © 2013 Copyright Taylor and Francis Group, LLC. Source

Parameswar L.,Db Pampa College | Parameswar L.,Cms College | Sreelatha K.S.,Amrita University | Joseph K.B.,Cms College
Journal of Nonlinear Optical Physics and Materials | Year: 2011

The propagation of two beams of light with slightly different frequencies through a photorefractive media is investigated. In this process, the refractive index experienced by either wave is modified with the intensity of the wave. The coupled nonlinear Schrödinger equation that models the beam propagation is derived from wave equation and solved analytically. The existence of soliton like solutions for the photorefractive media is also verified. © 2011 World Scientific Publishing Company. Source

Geetha P.,Db Pampa College | Geetha P.,Bishop Moore College | Latha M.S.,SN College | Pillai S.S.,N S S Hindu College | And 2 more authors.
Ecotoxicology and Environmental Safety | Year: 2015

Population explosion, depletion of water resources and prolonged droughts and floods due to climatic change lead to scarcity of pure and hygienic drinking water in most of the developing countries. Recently nanomaterials attained considerable attention as biosorbent for water purification purpose. However difficulties in removing polymeric surfactants and organic solvents used for nanoproduction and instability of the generated nanoparticles limit the scope of this approach in water cleanup. Here, we describe a novel green method for synthesizing polysaccharide nanoparticles in aqueous medium using honey as the capping agent. The highly stable alginate nanoparticles, characterized by various microscopic and spectroscopic techniques, exhibited a maximum uptake capacity of 333mgg-1of Pb(II) ions from aqueous solution. The effect of various parameters such as initial metal concentration, pH, contact time, temperature and adsorbent dose on sorption process was investigated in batch mode technique. The maximum removal percentage was 94.81 at 45°C and at pH 4.5 in 60min contact time. The biosorption followed Freundlich model indicating multilayer adsorption and pseudo second order kinetics. The mechanism involves both surface adsorption and pore diffusion. The positive values of δH°, S° and the negative value of δG°, confirmed the endothermic nature, randomness and spontaneity of biosorption process. © 2015 Elsevier Inc. Source

Geetha P.,Db Pampa College | Geetha P.,Bishop Moore College MavelikaraKerala | Latha M.S.,SN College | Pillai S.S.,N S S Hindu College | And 5 more authors.
Journal of Molecular Structure | Year: 2016

Green synthesis of nanoparticles has attained considerable attention in recent years because of its myriad of applications including drug delivery, tissue engineering and water purification. In the present study, alginate nanoparticles stabilized by honey were prepared by cross-linking aqueous solution of alginate with calcium ions. Honey mediated synthesis has been reported earlier for the production of metal nanoparticles. However no literature is available on the use of this technique for polymeric nanoparticles. Highly stable nanoparticles of 10-100 nm size were generated by this technique. The synthesised nanoparticles were characterized by transmission electron microscopy, scanning electron microscopy, atomic force microscopy, dynamic light scattering and Fourier transform infrared spectroscopic techniques. Potential of using these nanoparticles for heavy metal removal was studied by using Cr(VI) from aqueous solution, where a maximum removal efficiency of 93.5% was obtained. This method was also successfully employed for the production of other polymeric nanoparticles like casein, chitosan and albumin. © 2015 Elsevier B.V. All rights reserved. Source

Pillai S.S.,Bishop Moore College | Mullassery M.D.,Fatima Mata National College | Fernandez N.B.,Fatima Mata National College | Girija N.,Db Pampa College | And 2 more authors.
Ecotoxicology and Environmental Safety | Year: 2013

The biosorption capacity of chemically modified potato starch (CPS) for Cr(VI) from aqueous solution was investigated. The materials derived from carbohydrates are biodegradable and are generally regarded as safe and environmentally acceptable. The hydroxyl, carboxyl and carbonyl groups are responsible for the biosorption process. In the present study, the influence of various important parameters such as pH, time, biosorbent dose and initial Cr(VI) concentration on the biosorption capacity were investigated. The isotherms such as Langmuir, Freundlich and Tempkin were studied. The Freundlich and the Redlich-Peterson isotherms had been well fitted the biosorption of Cr(VI) with chemically modified potato starch. The kinetics of Cr(VI) removal using chemically modified potato starch was well explained by second-order kinetic model. The thermodynamic parameters were also evaluated from the biosorption measurements. Among the various desorbing agents tested, 98.2 percent chromium recovery was achieved with 0.1molL-1 NaOH. © 2013 Elsevier Inc. Source

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