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R. V. Fil'ts 《Journal of Mathematical Sciences》1993,65(6):1937-1940
Interpolation formulas for higher-order derivatives which guarantee the invariance of the results under changes of coordinates are obtained for functions of a vector argument.Translated from Matematicheskie Metody i Fiziko-Mekhanicheskie Polya, No. 25, pp. 22–25, 1987. 相似文献
205.
A model of an expanding and rotating universe is constructed in the framework of general relativity. The parameters of the model are compared with the fundamental observables and shown to be in good agreement.Kaluzhsk Branch, N. É. Bauman Moscow State Technical University (MGTU). Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 71–77, June, 1993. 相似文献
206.
A nonlinear integrodifferential equation that arises in polaron theory is considered. The integral nonlinearity is given by a convolution with the Coulomb potential. Radially symmetric solutions are sought. In the semiclassical limit, an equation for the self-consistent potential is found and studied. The potential has a logarithmic singularity at the origin, and also a turning point at 1. The phase shifts at these points are determined. The quantization rule that takes into account the logarithmic corrections gives a simple asymptotic formula for the polaron spectrum. Global semiclassical solutions of the original nonlinear equation are constructed.Moscow Institute of Electronic Engineering; Moscow Power Institute. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 97, No. 1, pp. 78–93, October, 1993. 相似文献
207.
A novel method for measuring AMP-deaminase activity in human erythrocytes is presented, based on the determination of the reaction product, IMP, using high performance liquid chromatography. IMP formation was found to be proportional both to the incubation time and the amount of haemolysate over a wide range. The minimal detectable AMP-deaminase activity was more than 1000 times lower than the mean activity found in healthy controls (1083 nmol/h/mg Hb). No marked difference of activity was found in the patients with the following inherited purine disorders: familial juvenile gouty nephropathy and deficiencies of adenosine deaminase, hypoxanthine-guanine phosphoribosyltransferase or adenine phosphoribosyltransferase. The activity in the erythrocytes of patients with chronic renal failure was also similar to controls. The existence of subjects with low erythrocyte AMP-deaminase activity in the population has been confirmed. 相似文献
208.
The reaction of CH3 with OH has been studied near 1200 K and 1 atmosphere pressure in shock tube experiments in which UV absorption was used to monitor [OH]. A rate coefficient of (1.1 ± 0.3) × 1013 cm3/mol-s was measured for removal of OH by CH3. This measured value is compared with previous experimental data and calculations. Several possible reaction channels are discussed, and although products were not monitored, it seems probable, on the basis of other work and theoretical estimates, that the primary mechanism (?75%) for the removal of OH by CH3 at these conditions is their combination to form CH3OH. Rate coefficients of (5.3 ± 0.8) × 1012 and (9.0 ± 1.4) × 1012 cm3/mol-s were measured for the reactions of OH with acetone and ethane, respectively, at the same temperature and pressure. 相似文献
209.
N. A. Volodin 《Journal of Mathematical Sciences》1992,59(4):885-890
Translated from:Problemy Ustoichivosti Stokhasticheskikh Modelei, Trudy Seminara, 1989, pp. 20–26. 相似文献
210.