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991.
992.
P.K. Chatterjee K.V. Vaidyanathan M.S. Durschlag B.G. Streetman 《Solid State Communications》1975,17(11):1421-1424
Low temperature (6°K) photoluminescence measurements have been performed on GaAs annealed under various conditions, to study defects generated by outdiffusion of the constituent atoms. Several defect-related luminescence peaks have been observed and associated with Ga and As outdiffusion. The outdiffusion of these elements during annealing to 850°C in vacuum and with Ga or As overpressure and SiO2 coatings is studied by monitoring the intensities of these peaks. 相似文献
993.
Ohne Zusammenfassung 相似文献
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997.
Copolymerization parameters of some halogen substituted phenolic monomers have been determined by the linear graphical method of Kelen and Tüdös. The order of reactivity of p-chlorophenol, p-bromophenol and p-iodophenol is found to be the reverse of the order of electronegativity of their halogen substituents when they are copolymerized with p-hydroxy-benzoic acid. On copolymerization with p-cresol, these halogen substituted phenols have reactivity in the same order as the electronegativity of their substituents. This reversal of reactivity of phenolic monomers has been interpreted in terms of (1) opposite polarization caused by electrophilic or nucleophilic substituents present in the common monomers, and (2) the magnitude of their resonance stabilization. The copolymerization parameters r1 and r2 are universally used for the characterization of monomer pairs with regard to their behavior in copolymerization. The classic copolymer equation describes the composition of the copolymer as a function of the reactivity ratios and the composition of the monomer feed. Several authors have used linear [1], nonlinear [2–6], specific coper composition equations [7], and computer programming routines [8] for calculating copolymerization parameters rl and r2. Kelen and Tödös [9] have recently. 相似文献
998.
999.
G. C. Bhar U. Chatterjee P. K. Datta S. Das R. S. Feigelson R. K. Route 《Applied physics. B, Lasers and optics》1991,53(1):19-22
Tangential near-noncritical phase matching is reported for upconversion in silver thiogallate (AgGaS2) using a dye laser as pump. A large acceptance angle for noncollinearity as desirable from a device view point is realised. Weak temperature tunability is also exploited to realise noncriticality. 相似文献
1000.
K. De J. Chatterjee A. K. Das S. K. Basu D. Basu 《Journal of Radioanalytical and Nuclear Chemistry》1992,166(5):383-391
Two single doses of X-ray radiation, i.e., 75 cGy and 4.0 Gy were applied on male Swiss albino mice. Quantitative changes in concentrations of trace metals like copper, zinc, cadmium and chromium in the whole body irradiated mice skin at several post-irradiated time intervals were studied in comparison to that of control animals. Observations indicate that irradiation induce redistribution of trace metals studied in skin at different post-irradiation time intervals. 相似文献