Browsing by Author "Shenvi, S."

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2-(2,4-Dichlorophenyl)-2-oxoethyl 4-methoxybenzoate
(2011) Fun, H.-K.; Chia, T.S.; Shenvi, S.; Isloor, A.M.; Garudachari, B.
In the title compound, C16H12Cl2O 4, the dihedral angle between the benzene rings is 70.11 (6) . In the crystal, molecules are linked by C-H?O hydrogen bonds into a three-dimensional network. A C-H?? inter-action is also observed.
2-(8-Bromoimidazo[1,2-a]pyridin-2-yl)-N?-[(E)-4-diethylamino-2- hydroxybenzyl-idene]acetohydrazide dihydrate
(2012) Fun, H.-K.; Loh, W.-S.; Shenvi, S.; Isloor, A.M.; Hegde, G.
In the title compound, C 20H 22BrN 5O 2 2H 2O, the Schiff base mol-ecule exists in an E conformation with respect to the acyclic C=N bond. An S(6) ring motif is formed via an intra-molecular O - H?N hydrogen bond. The dihedral angle between the imidazo[1,2-a]pyridine system and the benzene ring is 84.62 (5) . In the crystal, N - H?O, O - H?O, O - H?N, C - H?O and C - H?Br hydrogen bonds link the mol-ecules into a three-dimensional network. The crystal packing is further stabilized by C - H?? and ?-? inter-actions [centroid-centroid distance = 3.5365 (7) ].
Enhanced permeation performance of cellulose acetate ultrafiltration membranes by incorporation of sulfonated poly(1,4-phenylene ether ether sulfone) and poly(styrene- Co -maleic anhydride)
(2014) Shenvi, S.; Ismail, A.F.; Isloor, A.M.
A cellulose acetate (CA)-based ultrafiltration membrane was prepared by incorporation of mechanically strong, sulfonated poly(1,4-phenylene ether ether sulfone) (SPEES) to which hydrolyzed poly(styrene-co-maleic anhydride) (PSMA) was added as a novel additive. The preparation of SPEES was investigated in detail. SPEES having a degree of sulfonation of 21%, was more suitable for the blend. The chemical constitutions of SPEES, PSMA, and the blend membranes were confirmed by attenuated total reflectance fourier transform infrared spectroscopy. The scanning electron microscopy images revealed finger-like projections in the membrane structure. The performance of the membranes was analyzed on the basis of water content, porosity, flux, and antifouling studies. A membrane comprising 30% SPEES and 2% additive showed superior performance with flux and flux recovery ratio of 228 L/(m2 h) and 91%, respectively. It was concluded that the prepared membranes showed better performance in comparison with neat CA membranes. 2014 American Chemical Society.
Enhanced permeation performance of cellulose acetate ultrafiltration membranes by incorporation of sulfonated poly(1,4-phenylene ether ether sulfone) and poly(styrene- Co -maleic anhydride)
(American Chemical Society service@acs.org, 2014) Shenvi, S.; A.F., A.F.; Isloor, A.M.
A cellulose acetate (CA)-based ultrafiltration membrane was prepared by incorporation of mechanically strong, sulfonated poly(1,4-phenylene ether ether sulfone) (SPEES) to which hydrolyzed poly(styrene-co-maleic anhydride) (PSMA) was added as a novel additive. The preparation of SPEES was investigated in detail. SPEES having a degree of sulfonation of 21%, was more suitable for the blend. The chemical constitutions of SPEES, PSMA, and the blend membranes were confirmed by attenuated total reflectance fourier transform infrared spectroscopy. The scanning electron microscopy images revealed finger-like projections in the membrane structure. The performance of the membranes was analyzed on the basis of water content, porosity, flux, and antifouling studies. A membrane comprising 30% SPEES and 2% additive showed superior performance with flux and flux recovery ratio of 228 L/(m2 h) and 91%, respectively. It was concluded that the prepared membranes showed better performance in comparison with neat CA membranes. © 2014 American Chemical Society.
Preparation and characterization study of PPEES/chitosan composite membrane crosslinked with tripolyphosphate
(2014) Shenvi, S.; Ismail, A.F.; Isloor, A.M.
A novel composite membrane was prepared using chitosan (CH) as the active layer supported on a Poly(1,4-phenylene ether ether sulfone) (PPEES) membrane. The chitosan layer was ionically cross linked with sodium tripolyphosphate (TPP). The composite nature of PPEES/CH membranes was confirmed by Scanning Electron Microscopy (SEM). Infrared (IR) spectroscopy results and SEM-EDX analysis confirmed the crosslinking of chitosan surface with TPP. The membranes exhibited higher crosslinking density in acidic media than in basic media. The changes in the hydrophobic nature of PPEES membrane surface due to deposition of chitosan active layer followed by crosslinking were studied by their contact angle measurement, water flux and water uptake studies. The membranes showed rejection up to 55% and 21% towards MgSO4 and NaCl respectively at pH=5 and a flux recovery ratio of 73%. 2014 Elsevier B.V.
Preparation and characterization study of PPEES/chitosan composite membrane crosslinked with tripolyphosphate
(Elsevier, 2014) Shenvi, S.; A.F., A.F.; Isloor, A.M.
A novel composite membrane was prepared using chitosan (CH) as the active layer supported on a Poly(1,4-phenylene ether ether sulfone) (PPEES) membrane. The chitosan layer was ionically cross linked with sodium tripolyphosphate (TPP). The composite nature of PPEES/CH membranes was confirmed by Scanning Electron Microscopy (SEM). Infrared (IR) spectroscopy results and SEM-EDX analysis confirmed the crosslinking of chitosan surface with TPP. The membranes exhibited higher crosslinking density in acidic media than in basic media. The changes in the hydrophobic nature of PPEES membrane surface due to deposition of chitosan active layer followed by crosslinking were studied by their contact angle measurement, water flux and water uptake studies. The membranes showed rejection up to 55% and 21% towards MgSO4 and NaCl respectively at pH=5 and a flux recovery ratio of 73%. © 2014 Elsevier B.V.