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991.
Raj Kumar 《Colloid and polymer science》1979,257(2):206-209
Electrical potentials developed during streaming of methanol, water and their mixtures through a Zeokarb 225 (Al+++ form) membrane have been investigated. Build-up of streaming potential with time has been examined and discussed. Results indicate that dependence of streaming potential on applied pressure difference is non-linear and shows sign reversals. An attempt has been made to explain the results in terms of changes in the structure of electrical double layer at the membrane-permeant interface under the action of streaming pressure.With 4 figures 相似文献
992.
Cycloaddition of electron-deficient cyclohexa-2,4-dienones with nitroolefins leading to functionalized bicyclo[2.2.2]octenones with nitro groups is reported. A highly unusual regioselectivity was observed. Crystal structure of one of adducts has also been reported. 相似文献
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Proton nuclear magnetic resonance longitudinal relaxation rates are reported at 100MHz for CH4 and CHD3 in deuterium oxide solutions. The results demonstrate that methane reorients with a correlation time on the order of 0.1 psec, considerably faster than molecule correlation times in aqueous solutions. 相似文献
995.
Raj SG Kumar GR Raghavalu T Kumar P Mohan R Jayavel R 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(5):1021-1024
Single crystals of a new histidinium salt: L-histidinium trichloroacetate {abbreviated as LHTCA; [(C(3)N(2)H(4))CH(2)CH(NH(3))(CO(2))](+)CCl(3)COO(-)} were grown by slow evaporation of an aqueous solution at room temperature. The compound crystallizes in a non-centrosymmetric space group P2(1) of monoclinic system with cell parameters a=5.4505(18) A, b=25.769(8) A, c=9.210(2) A and beta=99.98(2) degrees. The vibrational structure of the compound confirms the presence of various functional groups in the molecule. The UV-vis-NIR spectrum shows a good transparency in the whole of the region from ultraviolet to near IR. The Kurtz powder SHG measurement confirms the frequency doubling of the crystal. Thermal behaviour of the crystals has been investigated by DSC analysis. These preliminary results suggest that LHTCA crystal can act as a potential and promising candidate for frequency doubling applications even from the near UV region to the near IR. 相似文献
996.
Raj Kumar Pernita Dogra 《International journal of environmental analytical chemistry》2013,93(3):280-290
Neodymium (III)-selective electrodes have been prepared by using tin (IV) antimonotungstate (SnSbW) and zirconium (IV) antimonotungstate (ZrSbW) as electro-active materials and epoxy resin as a binding material. In the case of SnSbW, best performance is exhibited by a membrane having the composition: tin (IV) antimonotungstate (50%) and epoxy resin (50%). It shows excellent response in the concentration range of 10–4?M to 10–1?M Nd (III) ion with a super-Nernstian slope of 40.0?mV/decade. It has a fast response time of 20 seconds and can be used for at least six months without any considerable divergence in potential. In the case of ZrSbW, best performance is exhibited by a membrane having the composition: zirconium (IV) antimonotungstate (40%) and epoxy resin (60%). It shows excellent response in the concentration range of 10–5?M to 10–1?M Nd (III) ion with a near-Nernstian slope of 25.0?mV/decade. It has a fast response time of 10 seconds and can be used for at least six months without any considerable divergence in potential. Effect of internal solution has been studied and the electrode was successfully used in partially non-aqueous medium, too. Selectivity coefficients have been determined by FIM method, with respect to alkali, alkaline earth, some transition and rare earth metal ions. ZrSbW electrode can be used in the pH range of 2.9–9.9 and SnSbW shows pH range 3.0–9.0. Both the electrodes have been used as indicator electrodes in the potentiometric titration of Nd (III) ions against EDTA. 相似文献
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