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11.
The neutrino-electron scattering in a dense degenerate magnetized plasma under the conditions μ
2 > 2eB ≫ μE is investigated. The volume density of the neutrino energy and momentum losses due to this process are calculated. The results
we have obtained demonstrate that plasma in the presence of an external magnetic field is more transparent for neutrino than
for non-magnetized plasma. It is shown that neutrino scattering under conditions considered does not lead to the neutrino
force acting on plasma. 相似文献
12.
Self-assembly of a binary monolayer of charged particles is modeled using molecular dynamics and statistical mechanics. The equilibrium phase diagram for the system has three distinct phases: an ionic crystal; a geometrically ordered crystal with disordered charges; and a fluid. We show that self-assembly occurs near the phase transition between the ionic crystal and the fluid, and that the rate of ordering is sensitive to the applied pressure. By assuming an Arrhenius form for the rate of ordering, an optimality condition for the temperature and pressure is derived that maximizes the rate. Using the Clausius-Clapeyron equation, the optimal point on the phase boundary is expressed in terms of the thermodynamic changes in state variables across the boundary. The predicted optimal temperature and pressure conditions are in good agreement with numerical simulations and result in self-organization rates five times that of a simulation without applied pressure. 相似文献
13.
N.I. Sorokin V.I. Makarov N.L. Lavrik Yu.M. Gusev G.I. Skubnevskaya N.M. Bazhin Yu.N. Molin 《Chemical physics letters》1981,78(1):8-12
The magnetic field and pressure effects in the photolysis of deuteroformaldehyde and sulfur dioxide in the near ultra-violet reagion have been investigated. A two-level model is proposed to interpret the results obtained. 相似文献
14.
15.
Using as an example the concentration dependence of the fluorescence quenching constants for quenching by Cd2+ ions for different weight fractions of humic acid, we have demonstrated the application of the fluorescence quenching method
for studying the effect of association on the structure of humic acids. We have established that the quenching constants for
the light fraction (5–30 kD) decrease as the humic acid concentration increases and the quenching constants increase for the
heavy fraction (60–100 kD). The observed dependences are interpreted in terms of the idea of oppositely directed effects of
association on the structure of the environment of fluorophores located within the core and peripheral regions of the humic
acid macromolecule. 相似文献
16.
Kohei Adachi Nickolay T. Trendafilov 《Advances in Data Analysis and Classification》2018,12(3):559-585
We propose a new procedure for sparse factor analysis (FA) such that each variable loads only one common factor. Thus, the loading matrix has a single nonzero element in each row and zeros elsewhere. Such a loading matrix is the sparsest possible for certain number of variables and common factors. For this reason, the proposed method is named sparsest FA (SSFA). It may also be called FA-based variable clustering, since the variables loading the same common factor can be classified into a cluster. In SSFA, all model parts of FA (common factors, their correlations, loadings, unique factors, and unique variances) are treated as fixed unknown parameter matrices and their least squares function is minimized through specific data matrix decomposition. A useful feature of the algorithm is that the matrix of common factor scores is re-parameterized using QR decomposition in order to efficiently estimate factor correlations. A simulation study shows that the proposed procedure can exactly identify the true sparsest models. Real data examples demonstrate the usefulness of the variable clustering performed by SSFA. 相似文献
17.
Nickolay A. Lutsenko 《Proceedings of the Combustion Institute》2013,34(2):2289-2294
A mathematical model and a numerical method, based on the combination of explicit and implicit finite difference schemes, have been developed for investigating the unsteady gas flows in porous objects with zones of heterogeneous combustion when gas pressure at object boundaries is known. Used approach enables to solve problems of filtration combustion for both forced filtration and free convection, so it can be efficiently applied for modeling the combustion zones in porous media, which may arise from natural or man-caused disasters. One-dimensional unsteady processes of heterogeneous combustion in porous object under free convection have been investigated using numerical experiment. Two regimes of combustion wave propagation have been revealed – wave movement up and down in the object – and it is shown that these regimes are significantly different in degree of burn of solid combustible material, the temperature in the combustion zone and propagation velocity of combustion wave. 相似文献
18.
Yu. M. Atroshchenko S. S. Golotvin I. V. Shakhkel'dyan O. V. Shishkin Zh. O. Lavrik O. Ya. Borbulevych M. Yu. Antipin E. N. Alifanova S. S. Gitis I. V. Ivanov A. Ya. Kaminsky 《Russian Chemical Bulletin》1999,48(9):1691-1695
cis, trans-6,8,10-Trinitro-1,4-dioxaspiro[4.5]decane was synthesized by reduction of the corresponding spirocyclic anionic δ-complex
with potassium tetrahydroborate. The molecular structure and the conformation of the title compound were established by X-ray
diffraction analysis and1H NMR spectroscopy.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1713–1717, September, 1999. 相似文献
19.
Irina YU. Gorbunova Michail L. Kerber Svetlana I. Vladimirova Reem R. Musleh Nickolay N. Avdeev 《Macromolecular Symposia》1998,127(1):187-192
Miscibility of polypropylene with some oligoesters was evaluated by optical wedge interference microscopy. Mechanical, thermal, rheological and relaxation properties were studied. Compatibility between the polymers and modifying agents was shown to have a marked effect on stress-strain properties as well as on the structure and melting characteristics of the modified polymers. 相似文献
20.