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941.
Chemical kinetics of benzonitrile nitration with mixed acid is investigated in the temperature range 283–299 K. Pseudo-first-order rate constants are evaluated by means of rate experiments on homogeneous reacting mixtures having large stoichiometric excesses of nitric acid. The second-order kinetic constants for nitronium ion attack to the aromatic substrate are derived on the basis of the assessed nitration mechanism. An activation energy of 604 ± 37 kJ mol?1 is calculated for this reaction step. © 1993 John Wiley & Sons, Inc. 相似文献
942.
The nonlinear Schrödinger-type equations invariant with respect to the extended Galilean group are described. We study the conditional symmetry of such equations, realize the reduction procedure, and construct the classes of exact solutions.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 4, pp. 539–551, April, 1993. 相似文献
943.
The hyperfine field andthe electric field gradient on Cd probe atoms at Ni(100) and Ni(111) surfaces are calculated self-consistently within the local density molecular/cluster approach. 相似文献
944.
V. G. Osmolovski 《Journal of Mathematical Sciences》1997,84(1):898-910
An existence theorem for the variational problem for the two-phase medium energy functional is proved. Dependence of the solution
on the surface tension coefficient and on the temperature is investigated. Bibliography: 7 titles.
Dedicated to V. A. Solonnikov on his sixtieth anniversary
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 213, 1994, pp. 131–150.
Translated by S. Yu. Pilyugin. 相似文献
945.
An iterative method from the class of completely implicit methods (CIM) is proposed for solving the equation of the velocity
potential of elliptical-hyperbolic type. The advantage of the proposed method compared to other CIM schemes is demonstrated
in application to mixed perfect gas flows in a nozzle of a given shape. Accuracy issues, rate of convergence, and various
techniques of ensuring stability in the hyperbolic region are discussed.
Translated from Chislennye Metody v Matematicheskoi Fizike, Published by Moscow University, Moscow, 1996, pp. 39–51. 相似文献
946.
A. P. Krauklis 《Journal of Mathematical Sciences》1997,86(3):2702-2704
This paper justifies the necessity of introducing corrections for the ray curvature into the standard procedure of the tomographic
inversion in the case of using traveltime data for the creeping waves. The results of relevant numerical experiments are presented.
Bibliography: 3 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 218, 1994, pp 67–71.
This work was supported by the Russian Foundation of Fundamental Research (Grant 93-05-9961).
Translated by A. P. Krauklis. 相似文献
947.
948.
949.
D. V. Peregoudov 《Theoretical and Mathematical Physics》1997,113(1):1331-1341
The effective potential method, used in quantum field theory to study spontaneous symmetry violation, is discussed from the
point of view of Bogoliubov’s quasi-averaging procedure. It is shown that the effective potential method is a disguised type
of this procedure. The catastrophe theory approach to the study of phase transitions is discussed and the existence of the
potentials used in that approach is proved from the statistical point of view. It is shown that in the case of broken symmetry,
the nonconvex effective potential is not a Legendre transform of the generating functional for connected Green’s functions.
Instead, it is a part of the potential used in catastrophe theory. The relationship between the effective potential and the
Legendre transform of the generating functional for connected Green’s functions is given by Maxwell’s rule. A rigorous rule
for evaluating quasi-averaged quantities within the framework of the effective potential method is established.
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 113, No. 1, pp. 149–161, October, 1997. 相似文献
950.