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121.
122.
Elisey Mazilov Evgeniya Ogurtsova Alexander Shamov Grigorii Khrapkovskii 《International journal of quantum chemistry》2010,110(4):939-945
Using nonempirical methods and DFT‐methods the geometrical parameters formation enthalpies of molecules and radicals, energies dissociation of N? NO2 bonds of primary and secondary N‐nitramines have been investigated. The basic tendencies in the changes of the geometrical and electronic structures, formation enthalpies, and dissociation energies have been analyzed in basic homologous series of nitramines. Various alternative mechanisms of the gas‐phase monomolecular thermal decomposition have been studied by of the example of N‐methylnitramine. The process of the aci‐form formation and its further multistage destruction is the most advantageous way of decomposition of the primary N‐nitramines. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010 相似文献
123.
Yu. V. Kokhanenko 《International Applied Mechanics》2011,47(6):700-706
Edge effects in a laminated composite with two isotropic components under uniaxial compression are studied. Grid equations
are derived using a modified variational difference method. Numerical results are analyzed 相似文献
124.
125.
126.
Erik Čižmár Daniela Šoltésová Olga N. Kazheva Grigorii G. Alexandrov Andrey V. Kravchenko Lyubov A. Chekulaeva Irina D. Kosenko Igor B. Sivaev Vladimir I. Bregadze Alexey V. Fedorchenko Vladimir A. Starodub Lev I. Buravov Oleg A. Dyachenko Alexander Feher 《Transition Metal Chemistry》2018,43(7):647-655
The synthesis of a radical-cation salt based on a derivative of tetrathiafulvalene, (ET)2[3,3′-Cr(1,2-C2B9H11)2] (ET?=?bis(ethylenedithio)tetrathiafulvalenium), was accomplished by electrochemical anodic oxidation of ET in the presence of (Me4N)[3,3´-Cr(1,2-C2B9H11)2] in the galvanostatic regime. An electric conductivity σ (293 K)?=?7 × 10?3 Ohm?1 cm?1 with semiconductor activation energy Ea???0.1 eV in the range of 127–300 K was observed. The crystal structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] was determined by X-ray diffraction at 173 K, revealing the presence of structural tetramers in radical-cation stacks. The magnetic properties of the complex were investigated in the temperature range 1.8–300 K using magnetometry and EPR, showing that the magnetic structure of (ET)2[3,3′-Cr(1,2-C2B9H11)2] consists of two independent magnetic subsystems. Cation radicals form a rectangular magnetic lattice in the ab-plane with significant antiferromagnetic exchange interactions. The chromium bis(dicarbollide) anions are characterized by unusually strong positive zero-field splitting of the Cr(III) ions, which was confirmed by ab initio calculations. 相似文献
127.
V. S. Shamanaev I. É. Penner M. M. Krekova G. P. Kokhanenko M. H. Saghafifar 《Russian Physics Journal》2005,48(12):1251-1256
Experiments on laser sensing of water under conditions simulating the operation of a laser radar mounted onboard an airplane
have been carried out. Values of water extinction index reconstructed from lidar signals are presented, and their dependence
on the lidar field-of-view angle is established. These data are compared with the results of calculations by the Monte Carlo
method. The experimental and calculated data are described by analytical expressions that differ only by proportionality coefficients.
Simultaneously with the lidar, the extinction index was measured with a reference submersible transmissometer. A regression
dependence between the lidar-derived extinction factors ε biased due to multiple scattering from their true values and the
reference values of ε measured with the transmissometer is obtained.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 12, pp. 34–39, December, 2005. 相似文献
128.
The paper is concerned with the determination of edge effect zone in a laminated composite with laminas subject to longitudinal
compression. The dependence of the maximum decay length on the ratio between the period of external loading and the structure
parameter is studied. The load period depends on the number of unloaded laminas. The decay of the edge effect is analyzed
by numerically solving a boundary-value problem of elasticity for piecewise-homogeneous materials and using a quantitative
decay criterion for the near-edge normal stresses
__________
Translated from Prikladnaya Mekhanika, Vol. 42, No. 8, pp. 89–96, August 2006. 相似文献
129.
Boris A. Trofimov Anastasiya G. Mal’kinaValentina V. Nosyreva Olesya A. ShemyakinaAlexander I. Albanov Andrei V. AfoninOlga N. Kazheva Grigorii G. AlexandrovOleg A. Dyachenko 《Tetrahedron letters》2012,53(8):927-930
Ethyl isonicotinate reacts with tertiary cyanoacetylenic alcohols under exceptionally mild conditions (room temperature, without catalyst or solvent) to afford novel polycondensed heterocyclic systems, 4,15-dioxa-7,12-diazapentacyclo[9.5.2.02,10.03,7.012,16]octadeca-8,17-dienes, in 30-68% yields. This tandem cyclization is regio- and stereospecific. Despite several asymmetric carbons (up to six) being present in the molecules, only one diastereomer is formed and both cyanomethylidene fragments possess exclusively Z-configuration. The tandem sequence includes the formation of 1,3-oxazolidino-1,2-dihydropyridines which undergo Diels-Alder cyclodimerization to give the final products. 相似文献
130.
Boris A. Trofimov Elena Yu. SchmidtElena V. Skitaltseva Nadezhda V. ZorinaNadezhda I. Protsuk Igor A. UshakovAlbina I. Mikhaleva Oleg A. DyachenkoOlga N. Kazheva Grigorii G. Aleksandrov 《Tetrahedron letters》2011,52(33):4285-4287
2-Alkylcyclohexanones react with arylacetylenes (KOH/DMSO, 100 °C, 1 h) to afford unexpectedly hexahydroazulenones in 34-50% yields and ca. 100% diastereoselectivity (instead of the expected acetylenic alcohols), the minor products being isomeric arylethenyl ketones. 相似文献