NOPR Collection:

Selective oxidation of p-methoxytoluene to p-methoxybenzaldehyde over supported vanadium oxide catalysts

Mon, 01 Sep 1997 00:00:00 GMT

Title: Selective oxidation of p-methoxytoluene to p-methoxybenzaldehyde over supported vanadium oxide catalysts Authors: Reddy, Benjaram M; Reddy, E P; Ganesh, I; Kumar, M Vijaya Abstract: Partial oxidation of p-methoxytoluene to p-methoxybenzaldehyde was studied in vapour phase at normal atmospheric pressure over titania, alumina, titania-alumina, titania-silica, titania-zirconia, titania-silica-zirconia, silica-zirconia, magnesia, calcia-magnesia supported vanadia catalysts. Vanadium oxide on basic supports, MgO and CaO-MgO, shows better selectivity towards p-methoxybenzaldehyde with considerable conversion of p-methoxytoluene at 673 K temperature. However, other acidic single and mixed oxide supported vanadium oxide catalysts exhibit poor selectivity at high conversion. Page(s): 256-258

Fluorometric determination of trichloroacetic acid and its application in water sample analysis

Mon, 01 Sep 1997 00:00:00 GMT

Title: Fluorometric determination of trichloroacetic acid and its application in water sample analysis Authors: Pal, Anjali; Bandyopadhyay, Manas Abstract: A simple and rapid method for the determination of trichloroacetic acid (TCA) at the parts per million (ppm) levels is developed. This is based on the photoreaction of TCA with diphenylamine (DPA) to give a fluorescent product (ʎ_em: 380 nm. ʎ_exc: 335 nm). The method has excellent reproducibility. The linear dynamic range for TCA is 20-200 ppm. Effects of reagent concentration, irradiation time and solvent are studied. The method is applicable to water analysis. Page(s): 253-255

Electrical resistivity of carbon fibres and their structural correlation by Mirage-FTIR spectroscopy

Mon, 01 Sep 1997 00:00:00 GMT

Title: Electrical resistivity of carbon fibres and their structural correlation by Mirage-FTIR spectroscopy Authors: Kumar, Ajay; Pandey, G C Abstract: The electrical resistivity of carbon fibres prepared at different carbonization temperatures has been reported. The resistivity data have been analyzed in the light of microstructural changes occurring at different stages of carbonization as revealed by Mirage-FTIR spectroscopic technique. The low resistivity of high modulus carbon fibre has been attributed to the increased graphitization. Page(s): 251-252

Mark-Houwink-Sakurada constants for cellulose-paraformaldehyde/dimethyl sulphoxide system

Mon, 01 Sep 1997 00:00:00 GMT

Title: Mark-Houwink-Sakurada constants for cellulose-paraformaldehyde/dimethyl sulphoxide system Authors: Tosh, B N; Saikia, C N Abstract: Mark-Houwink-Sakurada constants for cellulose paraformaldehyde/dimethyl sulphoxide system have been determined for characterization and simplification of the process for subsequent determination of molecular weight of any other cellulose sample. Page(s): 247-250