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1.
M. Yu. Kulikov A. M. Feigin G. R. Sonnemann 《Radiophysics and Quantum Electronics》2006,49(9):683-691
We propose a method for retrieval of directly unmeasurable concentrations of minor gas constituents of the mesosphere from
available experimental data using simplified models of atmospheric photochemical systems. The method is used for processing
of the results of simultaneous measurements of ozone and hydroxyl concentrations within the framework of the CRISTA-MAHRSI
satellite experiments. As a result, vertical distributions of concentrations of three more key chemical components of the
mesosphere, namely, atomic oxygen, atomic hydrogen, and hydroperoxide, were retrieved. It is shown that a limiting altitude-dependent
ratio between OH and O3 concentrations is valid in the mesosphere and lower thermosphere. It is found that CRISTA-MAHRSI data satisfy this ratio
up to an altitude of 87 km, but a strong discrepancy between theory and experiment arises in the upper region.
__________
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 49, No. 9, pp. 760–769, September 2006. 相似文献
2.
L. A. Valkova L. S. Shabyshev N. Yu. Borovkov L. A. Feigin F. Rustichelli 《Journal of inclusion phenomena and macrocyclic chemistry》1999,35(1-2):243-249
The effect is studied of the layer formation conditions on the molecular arrangement of copper tetra- tert-butyl phthalocyanine (CuPctBu4) and copper tetra- tert-butyl tetrabenzotriazaporphin (CuThptBu4) at the air–water interface. The decrease in initial surface concentration of these compounds is shown to affect the molecular orientation, as indicated by the increase in the area per molecule. The data are interpreted in terms of formation of CuPctBu4 and CuThptBu4 monolayers with a face-on molecular arrangement when the initial surface concentration is sufficiently small (N less than 1.6 × 10–7 mole/m2 for CuPctBu4 and N less than 4 × 10–7 mole/m2 for CuThptBu4) and changes in the molecular orientation to edge-on when the N values are higher. It is emphasized that the edge-on orientation on the water surface is not only a molecular but a collective property of the azaporphyrine supramolecular assembly. 相似文献
3.
4.
Rossmeisl J Kristensen I Gregersen M Jacobsen KW Nørskov JK 《Journal of the American Chemical Society》2003,125(52):16383-16386
The natural amino acids have different preferences of occurring in specific types of secondary protein structure. Simulations are performed on periodic model beta-sheets of 14 different amino acids, at the level of density functional theory, employing the generalized gradient approximation. We find that the statistically observed beta-sheet propensities correlate very well with the calculated binding energies. Analysis of the calculations shows that the beta-sheet propensities are determined by the local flexibility of the individual polypeptide strands. 相似文献
5.
An instability criterion based on the positivity of a Lyapunov-type exponent is used to study the stability of the Euler equations governing the motion of an inviscid incompressible fluid. It is proved that any flow with exponential stretching of the fluid particles is unstable. In the case of an arbitrary axisymmetric steady integrable flow, a sufficient condition for instability is exhibited in terms of the curvature and the geodesic torsion of a stream line and the helicity of the flow. 相似文献
6.
We propose a model to describe correlated two-electron dynamics in strong laser fields during laser-induced recollision between an electron and its parent ion. We derive an effective interaction potential which describes the effect of the laser-driven electron collision with an ion while retaining the correlation between the colliding and the bound electron. Using dissociative ionization of molecular hydrogen as an example, we analyze the dynamics of correlation-driven electron localization in a dissociating hydrogen molecular ion. 相似文献
7.
王柏懿 《应用数学和力学(英文版)》2003,24(8):928-935
By using Lagrangian method, the flow properties of a dusty-gas point source in a supersonic free stream were studied and the particle parameters in the near-symmetry-axis region were obtained . It is demonstrated that fairly inertial particles travel along oscillating and intersecting trajectories between the bow and termination shock waves . In this region, formation of " mufti- layer structure" in panicle distribution with alternating low- and high density layers is revealed. Moreover, sharp accumulation of particles occurs near the envelopes of particle trajectories . 相似文献
8.
Apart from the Knizhnik-Zamolodchikov differential equations, correlation functions in Wess-Zumino-Witten models of conformal field theory satisfy a certain system of algebraic equations. We show that hypergeometric solutions of KZ equations constructed in [3] do satisfy these algebraic equations. 相似文献
9.
We define a quantum-algebra associated to
as an associative algebra depending on two parameters. For special values of the parameters, this algebra becomes the ordinary-algebra of
, or theq-deformed classical-algebra algebra of
. We construct free field realizations of the quantum-algebra and the screening currents. We also point out some interesting elliptic structures arising in these algebras. In particular, we show that the screening currents satisfy elliptic analogues of the Drinfeld relations in.The research of the second author was partially supported by NSF grant DMS-9501414. 相似文献
10.
A. V. Gul'el'mi A. L. Kalisher F. Z. Feigin 《Radiophysics and Quantum Electronics》1995,38(9):586-588
We study the fluctuations of the repetition period of the Pc-1 geomagnetic pulsations propagating in the magnetosphere as packets of ion-cyclotron waves. A dimensionless parameter characterizing the frequency dependence of fluctuations is introduced. The value of this parameter and the repetition period of signals at a given frequency are used to evaluate the plasma density at an equator of the Pc-1 trajectory.Institute of Physics of the Earth, Russian Academy of Sciences, Moscow. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 38, No. 9, pp. 901–905, September, 1995. 相似文献