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We formulate and solve the problem of finding a distribution function F(r,p,t) such that calculating statistical averages leads to the same local values of the number of particles, the momentum, and the energy as those in quantum mechanics. The method is based on the quantum mechanical definition of the probability density not limited by the number of particles in the system. The obtained distribution function coincides with the Wigner function only for spatially homogeneous systems. We obtain the chain of Bogoliubov equations, the Liouville equation for quantum distribution functions with an arbitrary number of particles in the system, the quantum kinetic equation with a self-consistent electromagnetic field, and the general expression for the dielectric permittivity tensor of the electron component of the plasma. In addition to the known physical effects that determine the dispersion of longitudinal and transverse waves in plasma, the latter tensor contains a contribution from the exchange Coulomb correlations significant for dense systems. 相似文献
3.
Stochastic models of the process of spontaneous ignition of coal particles are distinguished by a pronounced nonlinearity due to the Arrhenius approximation for the constant of the reaction rate and by a complex structure of the stochastic component (noise). We present models describing the dynamics of the distribution of this quantity. The models obtained consist of nonlinear ordinary differential equations, which are solved by numerical methods with the use of computer technologies. 相似文献
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S. V. Shorshnev S. E. Esipov A. I. Chernyshev A. F. Pozharskii I. M. Nanavyan V. V. Kuz'menko 《Chemistry of Heterocyclic Compounds》1987,23(11):1247-1251
Unlike rheumycin and fervenulin, isofervenulin and 3-methylisofervenulin are hydrolyzed by aqueous alkalies at the N(5)-C(6) bond. On acidification of the reaction mixture, the N-carboxy-N-methylcarbamoyltriazines formed are reconverted into the starting isofervenulins, and on basification (pH>10) into methylaminotriazinecarboxamides. A by-product of the alkaline hydrolysis of isofervenulin is a product of the contraction of the uracil ring, namely imidazotriazinone-7a-carboxylic acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1555–1559, November, 1987. 相似文献
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A. F. Pozharskii V. V. Kuz'menko V. N. Koroleva G. G. Yurchuk 《Chemistry of Heterocyclic Compounds》1980,16(5):541-546
The action of concentrated sulfuric acid on perimidine and 2-substituted perimidines, 1,3-dimethylperimidinium perchlorate, and the 1,3-dimethyl derivatives of perimidone and 2,3-dihydroperimidine gave the 6(7)-sulfonic acids of these compounds.See [1] for communication 49.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 691–696, May, 1980. 相似文献
8.
L. N. Volovel'skii I. B. Skachek A. G. Selichenko I. I. Kuz'menko 《Chemistry of Natural Compounds》1980,15(4):435-441
It has been shown that under mild conditions the reactions of 17-hydroxy 3,20-diones of the pregnane series with acid hydrazides lead to the formation of 3-monohydrazones, while under severe conditions 3,20-dihydrazones are formed regardless of whether a C4–C5 ethylenic bond or a chain of conjugation of C4–C5 and C6–C7 ethylenic bonds is present in the steroid molecule. The reaction of 17-acetoxy 3,20-diketones of the pregnane series with acid hydrazides takes place only with the formation of 3-monohydrazones. An investigation of the gestagenic action of some of the compounds synthesized has shown that the presence of a 3-keto group in the steroids of the pregnane series is not necessary for the retention of this effect. The replacement of the keto group at carbon atom 3 by an azomethine group does not abolish the gestagenic action.Kharkov Scientific-Research Institute of Endocrinology and Hormone Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 501–509, July–August, 1979. 相似文献
9.
The values of partial molar free energy (G), enthalpy (H), and entropy (S) of sorption in the homologous series ofN-alkylpiperidines,N-alkylmorpholines,N-alkyl thiomorpholines, and alkylcyclohexanes were determined. It was found that the free energy of sorption is determined to a greater extent by the enthalpy term than by the entropy one. The free energy of sorption of the first homolog decreases when then-alkyl chain is attached directly to the carbon atom of the cycle and increases in the case ofN-alkylsubstituted heterocycles. The influence of the heteroatom nature on intermolecular interactions of homologs with the nonpolar stationary phase was quantitatively estimated on the basis of thermodynamic data.Dead time necessary for calculation of the retention factor was determined by the retention of methane injected into the column simultaneously with the sample.Translated from Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 8, pp. 2030–2032, August, 1996. 相似文献
10.
T. A. Kuz'menko V. V. Kuz'menko O. V. Kryshtalyuk A. F. Pozharskii 《Chemistry of Heterocyclic Compounds》1992,28(12):1461-1467
Reaction of 3-aryl-10-methyl-2H-1,3,4-thiadiazino[3,2-a]benzimidazolium salts with triethylamine led to ring contraction of the thiadiazine ring to a pyrazole ring with the formation of a mixture of derivatives of 3-mercaptopyrazolobenzimidazole and di(pyrazolo[1,5-a]benzimidazolyl-3) disulfide. The disulfides were formed exclusively when these salts react with ethanolic alkali. The reaction with potassium carbonate in acetic anhydridegave3-acetylthiopyrazolo[1,5- a]benzimidazoles. 2-Aryl-4- alkylpyrazolo[1, 5- a]benzimidazoles were formed by heating thiadiazino[3,2-a]benzimidazolium salts in formamide and by treating selenodiazino[3,2-a]benzimidazolium salts with potassium carbonate in acetic anhydride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1698–1705, 1992. 相似文献