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991.
The binding of the transition metal ions VO2+, Fe2+, Fe3+, CO2+, Co3+, Ni2+ and Cu2+ by a poly(iminoethylene) dithiocarbamate copolymer has been investigated by uptake studies and physical measurements (electronic, IR, and ESR spectra and magnetic susceptibility). Metal ions may be bound by both the dithiocarbamato and amino groups of the co-polymer. Binding to nitrogen (in addition to binding to sulphur) increases in the order FE(II)<Ni(II)<Cu(II) and accounted for increasing metal ion uptake by the copolymer in the same order. Factors which determine the relative uptake of the metal ions by the copolymer are discussed. 相似文献
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Elena M. Ivan'kova Marina Krumova Goerg H. Michler Peter P. Koets 《Colloid and polymer science》2004,282(3):203-208
The micromechanical behaviour of multilayered tapes made of two brittle incompatible amorphous polymers PS and PMMA was studied by means of an optical and a High Voltage Electron Microscope (HVEM). Microlayers of PS and PMMA were coextruded with varying number of layers: 64, 512 and 4096 layers. Mechanical properties of the PS/PMMA tapes were also examined. An increase in layer numbers was found to lead to a decrease in layer thickness that, in turn, resulted in: a) formation of thicker and longer crazes and, therefore, increased volume of the material involved in the plastic deformation; b) a noticeable increase in strength and strain at break (i.e. of toughness) of the samples. Enhanced toughness of the multilayered tapes is accounted for by massive cooperating crazing and yielding of both PS and PMMA phases. 相似文献
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Vladimir O. Gelmboldt Edward V. Ganin Larisa V. Ostapchuk Janusz Lipkowski Alexander A. Dvorkin Yurii A. Simonov Marina S. Fonari 《Journal of inclusion phenomena and macrocyclic chemistry》1996,24(4):287-299
Stable products have been obtained from the interaction of GeO2-HF solution with 18-membered crown ethers, 1,10-diaza-l8-crown-6 and 18-crown 6. Complexes were characterized by X-ray analysis and IR spectroscopy. Both Ge(IV) aquafluorocompounds are isostructural with their Si analogues. It was established that in the host-guest type complexes the germanium moiety as a central atom has been stabilized in the form of octahedral complexes. The host-guest interaction occurs by means of O-H(W)...Ocr, OH...F and N-H...F hydrogen bonds. 相似文献
1000.
The most important characteristics of capillary electrophoresis are studied. Principles of the technique, instrumentation employed and the most important applications are described. 相似文献