Search

Your search keyword '"Maity Arjun"' showing total 424 results
Start Over Author "Maity Arjun"
424 results on '"Maity Arjun"'

2. Degradation of insecticides used for indoor spraying in malaria control and possible solutions

Author

Massinga Pedro, Muiambo Herminio, Maity Arjun, Nhlapo Nontete S, Moyo Lumbidzani, Labuschagne Frederick JWJ, Focke Walter W, Sibanda Mthokozisi M, Crowther Nico AS, Coetzee Maureen, and Brindley Gordon WA

Subjects
Indoor residual spray, DDT, pyrethroid, carbamate, stabilization, Arctic medicine. Tropical medicine, RC955-962, Infectious and parasitic diseases, RC109-216
Abstract

Abstract Background The insecticide dichloro-diphenyl-trichloroethane (DDT) is widely used in indoor residual spraying (IRS) for malaria control owing to its longer residual efficacy in the field compared to other World Health Organization (WHO) alternatives. Suitable stabilization to render these alternative insecticides longer lasting could provide a less controversial and more acceptable and effective alternative insecticide formulations than DDT. Methods This study sought to investigate the reasons behind the often reported longer lasting behaviour of DDT by exposing all the WHO approved insecticides to high temperature, high humidity and ultra-violet light. Interactions between the insecticides and some mineral powders in the presence of an aqueous medium were also tested. Simple insecticidal paints were made using slurries of these mineral powders whilst some insecticides were dispersed into a conventional acrylic paint binder. These formulations were then spray painted on neat and manure coated mud plaques, representative of the material typically used in rural mud houses, at twice the upper limit of the WHO recommended dosage range. DDT was applied directly onto mud plaques at four times the WHO recommended concentration and on manure plaques at twice WHO recommended concentration. All plaques were subjected to accelerated ageing conditions of 40°C and a relative humidity of 90%. Results The pyrethroids insecticides outperformed the carbamates and DDT in the accelerated ageing tests. Thus UV exposure, high temperature oxidation and high humidity per se were ruled out as the main causes of failure of the alternative insecticides. Gas chromatography (GC) spectrograms showed that phosphogypsum stabilised the insecticides the most against alkaline degradation (i.e., hydrolysis). Bioassay testing showed that the period of efficacy of some of these formulations was comparable to that of DDT when sprayed on mud surfaces or cattle manure coated surfaces. Conclusions Bioassay experiments indicated that incorporating insecticides into a conventional paint binder or adsorbing them onto phosphogypsum can provide for extended effective life spans that compare favourably with DDT's performance under accelerated ageing conditions. Best results were obtained with propoxur in standard acrylic emulsion paint. Similarly, insecticides adsorbed on phosphogypsum and sprayed on cattle manure coated surfaces provided superior lifespans compared with DDT sprayed directly on a similar surface.

Published
2011
Full Text
View/download PDF

13. Polypyrrole Modified Granular Activated Carbon Nanocomposite for Treatment of Wastewater Containing Highly Toxic Hexavalent Chromium.

Author

Setshedi, Katlego Z., Kalombo, Lonji, Nomadolo, Nomvuyo, Hlekelele, Lerato, Ray, Suprakas Sinha, and Maity, Arjun

Subjects
HEXAVALENT chromium, ACTIVATED carbon, ADSORPTION kinetics, LANGMUIR isotherms, ADSORPTION capacity
Abstract

This study explored the fabrication of Polypyrrole (PPy) and Granular Activated Carbon (GAC) composites (PPy‐GAC) for effective removal of toxic hexavalent chromium (Cr(VI)) from aqueous solutions. Two synthesis methods are employed: (1) electrostatic deposition of PPy onto pre‐charged GAC paper and (2) in‐situ chemical polymerization of pyrrole monomer with GAC particles. Batch adsorption experiments investigated the impact of various operational parameters on Cr(VI) removal. Compared to pristine GAC (54.64 mg g−1), the PPy‐GAC composite exhibited a remarkable 3‐fold increase in equilibrium adsorption capacity, reaching 175.44 mg g−1. Pseudo‐second‐order kinetic model (R2 > 0.999) accurately described the adsorption kinetics, while the Langmuir isotherm model (R2 > 0.99) provided a good fit for the equilibrium data. Maximum adsorption capacity (qmax) increased with temperature, reaching 204.08, 243.90, and 270.27 mg g−1 at 298, 308, and 318 K, respectively. Furthermore, a fixed‐bed column experiment examined the composite's effectiveness in continuous Cr(VI) removal, demonstrating its suitability for practical applications. Notably, the PPy‐GAC composite successfully removed Cr(VI) from a real wastewater sample containing 68 µg L−1 Cr(VI) obtained from a ferrochrome industry, highlighting its potential for real‐world remediation. [ABSTRACT FROM AUTHOR]

Published
2024
Full Text
View/download PDF

16. Polymer-Based Magnetic Nanocomposites for the Removal of Highly Toxic Hexavalent Chromium from Aqueous Solutions

Author

Hato, Mpitloane J., Maponya, Thabiso C., Ramohlola, Kabelo E., Modibane, Kwena D., Maity, Arjun, Monama, Gobeng R., Makgopa, Katlego, Bello, Abdulhakeem, Lichtfouse, Eric, Series Editor, Schwarzbauer, Jan, Series Editor, Robert, Didier, Series Editor, Naushad, Mu., editor, Rajendran, Saravanan, editor, and Gracia, Francisco, editor

Published
2019
Full Text
View/download PDF

24. Polyaniline-Based Nanocomposites for Environmental Remediation

Author

C. Maponya, Thabiso, primary, J. Hato, Mpitloane, additional, R. Somo, Thabang, additional, E. Ramohlola, Kabelo, additional, D. Makhafola, Mogwasha, additional, R. Monama, Gobeng, additional, Maity, Arjun, additional, D. Modibane, Kwena, additional, and M. Katata-Seru, Lebogang, additional

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results