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151.
152.
IntroductionPoly( 3- alkylthiophenes) ( P3ATs) ,as a newkind of soluble,fusible and processable conductivepolymers,have attracted a great interest and muchattention ofchemistsand physicists[1,2 ] . Ithas beenwidely accepted that P3ATs can form similarlayered structures with alkyl side chains beingoriented in the lateral a- axis direction[3— 6] .Moreover,when the number of the carbon atoms inthe alkyl side chains is more than1 0 ,some orderlyarrangements of the side chains will occur between… 相似文献
153.
V. V. Gritsenko O. A. D'yachenko A. I. Kotov L. I. Buravov M. Mizuno 《Russian Journal of Coordination Chemistry》2001,27(6):401-406
A new molecular semiconductor, (Doet)2ReO4(Doet is (1,4-dioxanediyl-2,3-dithio)ethylenedithiotetrathiafulvalene), is synthesized and examined by X-ray diffraction analysis. The crystal structure of (Doet)2ReO4is formed by [Doet]+1/2layers with isle [ReO4]–anions located between them. The Doet radical cations from the adjacent layers are linked by intermolecular hydrogen interactions of the O···H type. 相似文献
154.
N. B. Ivchenko P. V. Ivchenko I. E. Nifant'ev V. V. Kotov 《Russian Chemical Bulletin》2000,49(5):942-945
An efficient synthetic approach to 3-alkyl(aryl)-2-bromoindenes was developed. The reaction of 2-bromo-3-tert-butylindene with MeMgl catalyzed by Ni(dppp)Cl2 afforded 3-tert-butyl-2-methylindene from which bis(3-tert-butyl-2-methylinden-1-yl)methane and the correspondingansa-zirconocene were synthesized. 相似文献
155.
本文先通过缩合反应合成羟端基的二酰亚胺单体, 然后利用亲核缩聚反应, 与4,4′-二氯二苯砜及3,3′-二磺酸钠基-4,4′-二氯二苯砜共聚, 制备聚合物. 该合成路线反应周期短, 对温度和溶剂等条件要求不高, 简便易得. 相似文献
156.
157.
V. G. Bazhenov V. L. Kotov S. V. Krylov V. V. Balandin A. M. Bragov E. V. Tsvetkova 《Journal of Applied Mechanics and Technical Physics》2001,42(6):1083-1089
An experimental method for determining the force of resistance to penetration of a deformable impactor into soft soil was developed in the inverted formulation: the impactor and the target exchange roles and the necessary parameters of contact interaction are recorded in an immovable measuring rod (impactor). To verify the basic principles of this experimental technique, wave processes were analyzed numerically using a modified Godunov's scheme. The applicability of various models of soil deformation was studied, and the calculation results obtained were compared with experimental data. 相似文献
158.
J. Badier J. Boucrot J. Bourotte G. Burgun O. Callot Ph. Charpentier M. Crozon D. Decamp P. Delpierre P. Espigat B. Gandois R. Hagelberg M. Hansroul Y. Karyotakis W. Kienzle P. Le D? J. Lefran?ois Th. Leray J. Maillard A. Michelini Ph. Mine G. Rahal O. Runolfsson P. Siegrist A. Tilquin J. Valentin R. Vanderhaghen S. Weisz NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1981,11(3):195-202
From π- interactions at 150 GeV/c on a heavy target, we present the final analysis of the dimuon decay angular distribution in the mass interval 4.5–8.5 GeV/c2. Results are presented and discussed in various reference frames and are also given in terms of the density matrix elements. Finally the possible contribution of higher-twist effects at largex 1 is discussed; we find that our data are not compatible with higher twist contributions as proposed by the Berger and Brodsky Model. 相似文献
159.
Telomerization of tetrafluoroethylene (TFE) with methanol in the presence of a free-radical initiator such as α, α′-azoisobutyronitrile
(AIBN) has been carried out. The product composition was related to kinetic equations involving the chaintransfer coefficients
and the concentration of telomeric fluoroalkanols obtained. 相似文献
160.