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51.
An investigation is undertaken into the variations observed in the cracking resistance, the plasticity, and the structure of an 82K3KhSR metallic glass upon annealing. A method of evaluating the mechanical properties and the structural state of metallic glasses is proposed. This method is based on the indentation of the metallic glass deposited onto a substrate prepared from a polyester material and a metal. The critical annealing temperature that corresponds to drastic changes in the mechanical properties of the metallic glass is determined. It is found that dependences of the cracking resistance of metallic glasses on the indenter load exhibit a linear behavior at annealing temperatures above the critical point. An exponential decrease in the cracking resistance upon indentation is observed with an increase in the annealing temperature of metallic glasses. 相似文献
52.
The response of the electrons of an fcc copper (001) film to an external electrostatic field is calculated. In order to determine the distribution of the screening charge, the equations of the electron density-functional theory are solved self-consistently by an original method. The position of the “image plane,” which is involved in a correct asymptotic expression for the exchange-correlation potential in the vacuum region, is first determined when performing a quantum-mechanical calculation for an anisotropic crystal film. The nonlinear electron response is characterized by the evolution of the “center of gravity” of the induced charge, which is also investigated. The calculations take into account the crystal structure of the film, and the results differ essentially from the predictions of the “jelly” model. 相似文献
53.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献
54.
55.
M.D. Seliverstov A.E. Barzakh I.Ya. Chubukov D.V. Fedorov V.N. Panteleev Yu.M. Volkov 《Hyperfine Interactions》2000,127(1-4):425-430
The study of nuclei far from stability requires high sensitivity of the experimental technique. The method of Resonance Ionization
Spectroscopy in a Laser Ion Source (RIS/LIS) allows one to carry out measurements of the isotope shifts and hyperfine splittings
for isotopes at the production rate about 102 atoms per second. The sensitivity of this method is determined by the high efficiency of the laser ion source and the low
background of the detection system afforded by characteristic α particle registration. The isotope shifts and hyperfine structures
of 155Yb, 154Tm (I=9 and I=2) and 153Tm (I=11/2) have been measured and the isotopic changes in mean square charge radii and nuclear electromagnetic moments have
been determined.
The further development of this experimental method – enhanced Target Ion Source system aimed to suppress thermionic background
– enables direct detection of the photoions and widens the range of the applicability of the RIS/LIS method.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
56.
V. V. Fedorov 《Computational Mathematics and Modeling》1992,3(1):1-10
Translated from Vychislitel'nye Kompleksy i Modelirovanie Slozhnykh Sistem, pp. 55–70, Moscow State University, 1989. 相似文献
57.
N. V. Vysotina A. S. Naumov N. N. Rozanov R. L. Sabirov V. E. Semenov V. A. Smirnov T. V. Starchikova S. V. Fedorov S. A. Chizhov V. E. Yashin 《Optics and Spectroscopy》2004,97(3):411-415
The final stage of self-focusing of 500-ps pulses of a neodymium laser in silicate and phosphate glasses and in the nonlinear liquids perfluorooctane, benzene, and toluene is studied theoretically and experimentally. The formation of spatial solitons, which are stable due to the nonlinearity saturation, is demonstrated. It is found that the intensity of the nonlinearity saturation is close to that of the threshold breakdown for glasses and the role of stimulated Raman scattering is significant for liquids. 相似文献
58.
Complexes of weakly coupled moving solitons are found by numerical solution of the generalized Ginzburg-Landau equation for the transversely one-dimensional scheme of a wide-aperture A-class laser with saturable absorption. As distinct from the case of complexes of motionless solitons, the phase difference between the neighboring moving solitons is close to 7π/2. 相似文献
59.
60.
Technical Physics - In this paper, we present the results of numerical simulation of explosive formation of a high-speed compact element from copper, steel, and aluminum cumulative liners combining... 相似文献