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31.
Procedures were developed for preparing representatives of a new type of halonitrothiolene 1,1-dioxides: mono- and dihalo derivatives of 2,2,4-tri- and 2,4-dinitro-3-thiolene 1,1-dioxides. An X-ray diffraction study showed that 2,5-dinitro-2,3-dichloro-3-thiolene 1,1-dioxide molecules exist in the crystal as enantiomeric pairs; the five-membered rings have the envelope conformation, with deviation of the sulfur atom from the ring plane; the halogen atom and nitro group at the multiple bond are essentially coplanar with the ring.  相似文献   
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1-Alkyl 3,5-bis(-hydroxyalkyl) isocyanurates were reacted with mercaptoacetic acid to obtain 3,5-bis(-mercaptoacetoxyalkyl) isocyanurates whose oxidation gives rise to macrocyclic disulfides.  相似文献   
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The molecular and crystal structure and the hydrogen bonding in crystal and in solutions of N-phenyl-N-(3,5-di-tert-butyl-4-hydroxybenzyl)thiourea and N-(3,5-di-tert-butyl-4- hydroxybenzyl)thiourea were studied by single crystal X-ray diffraction and IR spectroscopy. The intermolecular interactions of these compounds are essentially different.Translated from Zhurnal Obshchei Khimii, Vol. 74, No. 11, 2004, pp. 1864–1870.Original Russian Text Copyright © 2004 by Bukharov, Litvinov, Gubaidullin, Chernova, Shagidullin, Nugumanova, Mukmeneva.This revised version was published online in April 2005 with a corrected cover date.  相似文献   
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The propagation of acoustic waves in two-fraction mixtures of gas with vapor, droplets and solid particles of different materials and sizes in the presence of phase transitions is investigated. A mathematical model is presented, the dispersion and wave equations are obtained, and the dispersion curves are calculated. The relative sonic velocity and the attenuation decrement on the wave length are analyzed as functions of the oscillation frequency for an “air-vapor-liquid droplet-sand particle” mixture. Using the fast Fourier transform, the propagation of pulse disturbances in the two-fraction disperse systems is calculated.  相似文献   
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Russian Chemical Bulletin - Condensation of methyl phenyl(alkyl)halopyrotartrates with N,N′-diphenylselenourea leads to the formation of methyl...  相似文献   
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The properties are studied of the propagation of unsteady shock waves in a gas-liquid system of bubble structure in the case when the volume concentration of the gas changes in the direction of motion of the shock wave. It is established that when there is a sufficiently rapid drop in the gas content, an effect of amplification of the shock wave is observed which is due to the deceleration of the medium behind the shock wave. A study is made of the laws of the evolution of long- and short-wave pulsed perturbations in such systems. The authors consider processes of reflection of waves from obstacles and their passage from a gas into a bubble liquid, from a two-phase mixture into a pure liquid. The contribution is determined of nonequilibrium effects to the process of amplification of a wave.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 1, pp. 49–54, January–February, 1988.The authors wish to express gratitude to R. I. Nigmatulin for his interest in the study and for useful discussions.  相似文献   
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Phosphorylation of 2-hydroxyphenyl 2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl ketone with dichloro(phenyl)phosphine gave 5-oxo-2-phenyl-4,4-bis(trifluoromethyl)-4,5-di-hydro-1,3,2-benzodioxaphosphepine. Heating of the latter initiated an intramolecular interaction of the P atom with the carbonyl group. Hydrolysis of the intermediate product yielded 3-hydroxy-2-oxo-2-phenyl-3-[2,2,2-trifluoro-1-hydroxy-1-(trifluoromethyl)ethyl]-2,3-di-hydro-1,2λ5-benzo[d]oxaphosphole. The reaction was highly stereoselective (PRCS/PSCR). The reaction of the starting phosphepine with chloral proceeded highly stereoselectively (PRCSCS/PSCRCR) to give a 5-carbaphosphatrane derivative containing a four-membered ring, namely, 1-phenyl-3-trichloromethyl-10,10-bis(trifluoromethyl)-6,7-benzo-2,4,8,9-tetraoxa-1λ5-phosphatricyclo[3.3.2.01,5]decene. The trigonal bipyramid of the 5-carbaphosphatrane derivative is made up of the equatorial O atoms and the apical C atoms.  相似文献   
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