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51.
The dependences of the energy that is absorbed in a crystal exposed to the action of a femtosecond light pulse on the radiation intensity at a fixed pulse duration and on the pulse duration at a fixed pulse energy have been determined under the conditions of a two-photon–one-photon double resonance on interband transitions in the crystal.  相似文献   
52.
We propose a molecular-statistical model of organization of the epitropic liquid-crystal phase, according to which the presence of fluctuation associates in the bulk of the liquid and active (adsorption) centers on the solid substrate is essential for the formation of this phase. Using this model, it is possible to describe the experimental temperature dependence of the thickness of the epitropic liquid-crystal layer of nitrobenzene on quartz. Quantitative agreement between the theory and experiment is reached in the close proximity (~10 K) of the crystallization temperature. Important thermodynamic parameters of the model can be corrected from comparison with experimental results.  相似文献   
53.
An approach devised earlier is generalized for a binodal line and used to analyze experiments on a broad set of fluids from He4 to organic compounds. Experimental binodal lines and isothermal compressibility are described with precision for the above substances. The error characterizing the theory’s deviation from the experimental data is several times lower than in a similar analysis using the Ising model.  相似文献   
54.
New chiral oxazoline-containing phosphoramidite was synthesized and its complex formation with rhodium(i) and palladium(ii) was examined. The new ligand is a highly efficient chiral inductor (ee up to 92%) in palladium-catalyzed asymmetric sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate.  相似文献   
55.
By using observations of solutions of the first initial boundary-value problem for a parabolic quasilinear equation with fast random oscillations, we estimate the nonlinear term of the equation. In the metric of the space L2, we study large deviations of a nonparametric estimate of nonlinear influence.  相似文献   
56.
57.
Differential Equations - Using a particular example, we constructively prove that the convergence of all solutions of a nonautonomous two-dimensional differential system to zero at infinity does...  相似文献   
58.
Described is the asymmetric synthesis of the allylic alcohols 11 (85% ee), 15 (99% ee), 17 (93% ee), 19 (61% ee), and 21 (69% ee) through a Pd-catalyzed reaction of the unsymmetrical carbonates rac-10, rac-12, rac-14, rac-16, rac-18, and rac-20, respectively, with KHCO3 and H2O in the presence of bisphosphane 6. Similarly the allylic alcohols 23 (99% ee) and 25 (97% ee) have been obtained from the symmetrical carbonates rac-22 and rac-24, respectively. Reaction of the meso-biscarbonate 26 with H2O and Pd(0)/6 afforded alcohol 27 (96% ee), which was converted to the PG building block 32. The unsaturated bisphosphane 33 showed in the synthesis of alcohols 36, 37, and 39 a similar high selectivity as 6. The formation of alcohols 11, 15, and 17 involves an efficient dynamic kinetic resolution.  相似文献   
59.
Conclusions Syntheses are reported for ,-dithioalkyldivinyl ketones, which react with ammonia to give -amino--thioalkyldivinyl ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2414–2415, October, 1988.The authors thank A. M. Kachurin for assistance in taking the spectra.  相似文献   
60.
The approximation of reduced linear evolution operator (propagator) via dynamic mode decomposition (DMD) is addressed for both linear and nonlinear events. The 2D unsteady supersonic underexpanded jet, impinging the flat plate in nonlinear oscillating mode, is used as the first test problem for both modes. Large memory savings for the propagator approximation are demonstrated. Corresponding prospects for the estimation of receptivity and singular vectors are discussed. The shallow water equations are used as the second large‐scale test problem. Excellent results are obtained for the proposed optimized DMD method of the shallow water equations when compared with recent POD‐based/discrete empirical interpolation‐based model reduction results in the literature. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
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