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71.
Herein we report a study of highly efficient platinum‐catalyzed hydrosilylation of dialkenylgermanes with silsesquioxanes and spherosilicates. The use of divinyl‐ and diallylgermanes allowed the synthesis of new classes of compounds, i. e., dumbbell‐type systems, silsesquioxanes with alkenyl pendant group, and oligomeric derivatives. The results are supported by detailed data from in situ FT‐IR and NMR measurements, enabling precise monitoring of the reaction progress and determination of regioselectivity of the formed products. 相似文献
72.
Bogdan Marciniec Mariusz Lewandowski 《Journal of polymer science. Part A, Polymer chemistry》1996,34(8):1443-1445
Acyclic diene polymerization (ADP) of divinyldimethylsilane in the presence of ruthenium RuCl2(PPh3)3 and rhodium [RhCl(cod)]2 catalysts led predominantly to linear silylene-vinylene oligomers (Mn = 1510 and Mw/Mn = 1.19) if the ruthenium catalyst was used or to mixture of cyclic and linear oligomers if rhodium complex was catalyst. © 1996 John Wiley & Sons, Inc. 相似文献
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75.
Anamaria Durdureanu-Angheluta Lucia Pricop Catalina-Anisoara Peptu Narcisa Marangoci Horia Chiriac Bogdan C. Simionescu 《Journal of magnetism and magnetic materials》2010,322(19):2956-2968
New silicon magnetite ferrofluids were prepared by dispersing siloxane-coated magnetite particles in polydimethylsiloxane with low or high molecular weights. Ferrofluids are stable colloidal dispersions of ultra fine covered magnetite particles, which may be selected for a specific application. We demonstrated new methods of stabilizing the magnetic particles by reacting the hydroxyl groups on the surface of magnetite particles with terminal ethoxy groups of polydimethylsiloxane, followed by their dispersion in silicon fluids. The new silicon ferrofluids were tested from the morphology, magnetic properties/losses, and rheological properties point of view. 相似文献
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77.
Different properties of recently introduced Paired Haar transform have been shown. Nonpolynomial Haar Pxpansion of incompletely specified Boolean functions has been presented. Based on the above properties and expansion some applications of Paired Haar spectrum have been proposed. Algorithm for the calculation of Haar Pair spectrum from disjoint cubes for systems of incompletely specified Boolean functions has also been developed. 相似文献
78.
Self-consistent Hartree-Fock and RPA calculations with the Skyrme-type interaction SGII are used for a systematic investigation of the 1+ and the triplet 0?, 1?, 2? states in 40Ca and 208Pb. Response functions to spin-dependent multipole operators are calculated and the particle-hole structure of the spin-dependent collective states is studied. Collective spin-dependent 0? and 1? states above the giant dipole resonance as well as a collective spin-independent 2? state (twist mode) are identified. Transition spin and current densities are calculated for the collective excitations and found to be useful for the study of these excitation modes. 相似文献
79.
Bogdan M. Baishanski 《Journal of Approximation Theory》1984,40(4):384-390
Approximation of a monomial by incomplete polynomials was the subject of several investigations. Here the setting is inverted (approximating a polynomial by monomials) and generalized (approximating a polynomial by incomplete polynomials). 相似文献
80.
D. Bogdan T. Cretu G. Macarie M. I. Chernej 《Zeitschrift für Physik A Hadrons and Nuclei》1973,263(2):121-128
The wave functions yielded by the microscopical non-adiabatic treatment of the Coriolis interaction proposed in Dubna by Pyatov, Chernej and Baznat have been used in order to calculate the beta decay observables of some allowed transitions of the155Eu nucleus. The Coriolis interaction effects are important especially for the absoluteft values (an important improvement is obtained) and for theβ-γ circular polarization correlation. 相似文献