Narayan C Pradhan
Articles written in Bulletin of Materials Science
Volume 25 Issue 6 November 2002 pp 533-536
Tarakranjan Gupta Narayan C Pradhan Basudam Adhikari
Hydroxyterminated polybutadiene (HTPB) was reacted with 2,4-toluene diisocyanate (TDI)followed by the addition of a diamine chain extender (prepared by the condensation reaction of 4,4′-diaminodiphenylsulfone and terepthalaldehyde) to prepare an imine containing polyurethaneurea (PIUU). The prepared polyurethaneurea was caste in order to obtain polymer film. The new polyurethaneurea film showed high phenol selectivity as pervaporation membrane. About 88% phenol was obtained in condensed permeate when pervaporation was performed at 50°C with 7% aqueous phenol solution as feed and permeate side pressure was maintained at 5 mm of Hg.
Volume 27 Issue 6 December 2004 pp 555-564 Fly Ash
Zeolite from fly ash: synthesis and characterization
Keka Ojha Narayan C Pradhan Amar Nath Samanta
Coal fly ash was used to synthesize X-type zeolite by alkali fusion followed by hydrothermal treatment. The synthesized zeolite was characterized using various techniques such as X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, BET method for surface area measurement etc. The synthesis conditions were optimized to obtain highly crystalline zeolite with maximum BET surface area. The maximum surface area of the product was found to be 383 m2/g with high purity. The crystallinity of the prepared zeolite was found to change with fusion temperature and a maximum value was obtained at 823 K. The cost of synthesized zeolite was estimated to be almost one-fifth of that of commercial 13X zeolite available in the market.
Volume 29 Issue 3 June 2006 pp 225-231 Biomaterials
Ujjal K Ghosh Narayan C Pradhan Basudam Adhikari
Hydroxyterminated polybutadiene (HTPB) based porous polyurethaneurea (PUU) membranes were prepared. The porosity was developed by incorporation of lithium chloride into polymer matrix with subsequent leaching of the same in hot water. Scanning electron microscopic analysis of the prepared membrane surfaces was performed. The pervaporation performance of the synthesized membrane was studied with aqueous 4-nitrophenol solution as feed. The effects of various parameters on 4-nitrophenol separation factor and total as well as 4-nitrophenol flux were studied. Polyurethaneurea membrane was found to permeate 4-nitrophenol selectively with high separation factors for the organic component. Pore size and number of pores on the surface of the membrane were calculated from SEM image of the membranes. Effects of pore size and porosity on pervaporation flux were also investigated.
Volume 45, 2022
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Prof. Subi Jacob George — Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru
Chemical Sciences 2020
Prof. Surajit Dhara — School of Physics, University of Hyderabad, Hyderabad
Physical Sciences 2020
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