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31.
The Schmidt reaction in oleum is used to prepare 2, 3-and 4-aminopyridines.  相似文献   
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We study the possibilities of the chemical analysis of materials with determination of the positions of individual atoms of various chemical elements in a sample using an APPLE-3D atom probe tomograph with femtosecond-laser assisted evaporation, developed at the Institute of Theoretical and Experimental Physics of the National Research Center “Kurchatov Institute.” The results of investigations of ferritic-martensitic steels and an aluminum alloy are presented; the characterization and visualization of features with a size on the order of 10 nm are demonstrated.  相似文献   
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Journal of Russian Laser Research - We study the photo-ionization mechanism of molecular oxygen at the 222 nm KrCl laser wavelength within a laser pulse intensity range of 108 – 1010 W/cm2,...  相似文献   
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A two-scale approach to the simulation of mechanical properties of metallic materials is considered. On the macroscopic level, the material behavior is described by a phenomenological model of finite strain viscoplasticity with nonlinear kinematic hardening. In particular, the process-induced plastic anisotropy is captured by backstresses. On the microstructural level, the so called “load path sensitive two-population dislocation cell model” is implemented. It describes an evolving dislocation cell structure with dislocation populations for dislocation cell walls and the cell interior. Owing to the coupling with the phenomenological plasticity model, it can describe the evolution of the dislocation densities depending on the load path. The applicability of the multiscale approach to the FEM simulation of severe plastic deformation processes such as Equal Channel Angular Pressing is demonstrated. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
36.
A mechanism for the degradation of Sulfonol in its aqueous solutions acting as a liquid cathode of atmospheric-pressure dc discharge in air and for the formation of the products has been proposed, and the chemical kinetics of the degradation processes has been numerically simulated.  相似文献   
37.
The linear electrodynamic problem of the stability of a viscous liquid surface at the liquid-air interface is studied in view of the surface charge kinetics. The electric field critical intensities which break the stability of the plane interface are determined. Conditions for generating sustained waves at the interface are found.  相似文献   
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This paper reports the results of the experimental study of parameters for a DC oxygen discharge with water cathode in the pressure range of 0.1–1 bar and the discharge current of 40 mA. The radius of positive column, the cathode voltage drop, the cathode current density and the electric field strength were measured. Rotational temperatures of N2 (C3Πu, V = 0) and OH (A2Σ, V = 0) and absolute line intensities of atomic oxygen with wave length of 845 and 777 nm were determined as well. Plasma composition modeling was carried out by the combined solution of the Boltzmann equation for electrons, the equations of vibrational kinetics for ground states of N2, O2, H2O molecules, and the equations of chemical kinetics, and the plasma conductivity equation. Calculations were carried out taking into consideration the discharge radial heterogeneity and using experimental values of E/N and gas temperatures. The main particles being formed in plasma were shown to be ·OH, H2O2, O(3P), O2(a1Δg), O2(b1Σ g + ), H(1S). On the basis of this calculation and experimental values of line intensities, the populating mechanism of (3p 3P) level of atomic oxygen was discussed. The comparison of some properties of discharges in O2, N2 and air was done.  相似文献   
40.
The forthcoming F acility for A ntiprotons and I on R esearch (FAIR) at Darmstadt, is going to be a unique accelerator facility that will deliver high quality, strongly bunched, well focused, intense beams of heavy ions that will lead to unprecedented specific power deposition in solid matter. This will generate macroscopic samples of H igh E nergy D ensity (HED) matter with fairly uniform physical conditions. These samples can be used to study the thermophysical and transport properties of HED matter. Extensive theoretical work has been carried out over the past decade to design numerous dedicated experiments to study HED physics at the FAIR, which has provided the basis for the HEDgeHOB ( H igh E nergy D ensity Matter Ge nerated by H eavy I o n B eams) scientific proposal. This work is still in progress as the feasibility studies for more experimental schemes are being carried out. Another, very important research area that will benefit tremendously from the FAIR facility, is the production of radioactive beams. A superconducting fragment separator, Super–FRS is being designed for the production and separation of rare radioactive isotopes. Unlike the HED targets, the Super–FRS production target should not be destroyed or damaged by the beam, but should remain intact during the long experimental campaign. However, the high level of specific power deposited in the production target by the high intensity ion beam at FAIR, could cause serious problems to the target survival. These HED issues related to the Super–FRS production target are also discussed in the present paper (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
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