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141.
Tamara Borisova Sergey Fridrikh Yuli Gotlib Grigoriy Medvedev Natalja Nikonorova Sergey Skorokhodov Vjacheslav Zuev 《Macromolecular Symposia》1993,72(1):67-80
A series of thermotropic main chain polymers with extended dimethylsiloxane segments was investigated. The study of dielectric properties of polymers revealed the relationship between their ability to form a mesophase and their molecular mobility. The peculiar behaviour of dielectric α-relaxation parameters during the transition from mesomorphic to isotropic members of this polymeric series was shown. The theoretical approaches were developed for understanding macrochain dynamics of liquid crystalline polymers. The theoretical and experimental results are in good agreement. 相似文献
142.
V. Tamara Perchyonok 《Tetrahedron letters》2006,47(29):5163-5165
(TMS)3CH is an efficient free radical reducing agent. Debromination, deiodation, dechlorination as well as decarboxylation of Barton and Kim esters can proceed smoothly using this tin-free reducing agent. Rate constants for hydrogen atom abstraction from TMS3CH by primary radicals were also determined. 相似文献
143.
144.
M. I. Adamovich M. M. Aggarwal Y. A. Alexandrov N. P. Andreeva Z. V. Anson R. Arora F. A. Avetyan S. K. Badyal E. Basova K. B. Bhalla et al. 《Zeitschrift fur Physik C Particles and Fields》1992,56(4):509-520
The energy and centrality dependence of local particle pseudorapidity densities as well as validity of various parametrizations of the distributions are examined. The dispersion, , of the rapidity density distribution of produced particles varies slowly with centrality and is 0.80, 0.98, 1.21 and 1.41 for central interactions at 3.7, 14.6, 60 and 200A GeV incident energy, respectively, is found to be independent of the size of the interacting system at fixed energy. A novel way of representing the window dependence of the multiplicity as normalized variance versus inverse average multiplicity is outlined. 相似文献
145.
Kseniya N. Sedenkova Elena B. Averinax Anna A. Nazarova Yuri K. Grishin Dmitry S. Karlov Vladimir L. Zamoyski Vladimir V. Grigoriev Tamara S. Kuznetsova Vladimir A. Palyulin 《Mendeleev Communications》2018,28(4):423-425
A convenient approach to novel symmetric bispyrimidine diamines comprises SNAr reactions of 4-fluoropyrimidine N-oxide with alkane-α,ω-diamines with subsequent reduction of N-oxide function. The obtained substances were tested in patch-clamp experiments for the influence on the kainateinduced currents in Purkinje neurons and showed negative modulating effect. 相似文献
146.
147.
Tamara R. Nauman Mark L. McLaughlin Frank R. Fronczek Steven F. Watkins 《Journal of chemical crystallography》1996,26(2):107-110
5, 6, 11, 12-Tetrabromo-5, 6, 11, 12-tetrahydrodibenzo[a, e]cyclooctene, C16H12Br4, crystallizes in monoclinic space group P21/c witha=8.6917(7),b=15.135(2),c=12.892(2) Å, =101.836(8)°, V=1660.0(7) Å3,Z=4. The structure was refined toR=0.058 for 3137 observed reflections. The molecule has approximate C2 symmetry, with the eight-membered ring adopting the twist-boat conformation. The planes of the two phenyl rings form a dihedral angle of 117.3(2)°, C–Br distances range 1.965(5)–1.981(5) Å. 相似文献
148.
S. A. Krasnov T. N. Maksimkina G. J. Musulmanbekov F. Schussler A. Dirner L. Just M. Karabová A. Pavuková M. Tóthová S. Vokál J. Vrláková B. Jakobsson K. Soderstrom M. I. Adamovich M. M. Chernyavsky S. P. Kharlamov V. G. Larionova G. I. Orlova N. G. Peresadko N. A. Salmanova M. I. Tretyakova E. S. Basova S. Z. Nasyrov N. V. Petrov T. P. Trofimova U. I. Tuleeva B. P. Tursunov B. S. Yuldashev K. G. Gulamov V. S. Navotny I. D. Ohja B. K. Singh V. Singh S. K. Tuli 《Czechoslovak Journal of Physics》1996,46(6):531-540
Inelastic interactions induced by84Kr nuclei at 800–950 MeV/nucleon have been studied using a high angular resolution emulsion detector. Data on multiplicities of the produced particles, projectile and target fragments are shown. Comparisons with cascade calculations have been performed.We thank to Swedish Research Council for Natural Sciences for the financial support. Scanning and measurements performed by E.G. Broomé and V. Kopljar are acknowledged. 相似文献
149.
Chromium nitride and chromium oxide were deposited by arc PVD and APS on steel substrates to be worn in a testing set up simulating the abrasion process of a screw rotor compressor. The damage of Cr
x
N is more severe than that of Cr2O3. The abrasive particles were collected on glassy carbon with a Batelle impactor and analyzed by AES and REM. Particles from the Cr
x
N coating are totally oxidized, in contrast to particles from Cr2O3 which are not chemically influenced. No oxidation can be detected on the surface of the treated Cr
x
N coating. The Cr2O3 coating is not affected either.Dedicated to Professor Dr. rer. nat. Dr.h.c. Hubertus Nickel on the occasion of his 65th birthday 相似文献