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61.
Alekseev S. V. Andreev Yu. M. Losev V. F. Lubenko D. M. 《Russian Physics Journal》2020,62(11):2151-2155
Russian Physics Journal - This paper presents the results of research on parameters of the THL-100 hybrid laser system of the visible spectrum with a view to modernizing it, in order to achieve the... 相似文献
62.
The chemical etching technique was used to study the precipitation-induced dislocation microstructures in NaCl:Ni crystals with 110 rod-like precipitates. The comparison was made of the results obtained by the etch pit and decoration studies. The coincidence of the patterns suggests the prismatic dislocation loops and helices of the interstitial type to be only produced at elevated temperatures (above 300°C). The smallest size loops are removed by climb on slow cooling. These loops sometimes persist in quenched crystals. 相似文献
63.
The microhardness and bulk density variations with annealing temperature have been measured in NaCl crystals doped with Ca2+, Cd2+, Ni2+, and Pb2+. Both characteristics are not affected by coherent metastable precipitation while incoherent precipitation produces either hardening or softening depending on the impurity phase type (stable or metastable). The results support the suggestion that aggregates and coherent precipitates are cut through by dislocations whereas incoherent precipitates are by-passed via the Orowan looping mechanism. 相似文献
64.
Using the decoration technique, the dislocation structure has been observed in regions localized near precipitates in nickel-doped NaCl crystals. The results are interpreted in terms of the stress-operated mechanism for the generation of prismatic dislocations by the precipitates. Normally only two of twelve possible slip directions operate for 〈110〉 rods. This is accounted for in terms of the climb and disappearance of dislocation loops corresponding to the other directions. {100} plates produce loops spreading along for 〈110〉 directions. 相似文献
65.
V. M. Andreev O. K. Salieva V. A. Solov'ev O. V. Sulima A. M. Khammedov 《Crystal Research and Technology》1988,23(12):1531-1537
It is shown by microcathodoluminescence and electron beam induced current investigations that efficiency of radiative recombination and the values of hole diffusion lengths in nGaAs substrate increase (up to Lp ∽ 5 μm) due to an annealing under Ga Al melt. The values of the annealing critical temperature exceeding of which leeds to bulk non-radiative recombination drop as well as optimal values of annealing temperature and duration are determined. In pAlGaAs–(p-n)GaAs solar cells based on annealed substrates the values of open circuit voltage Uoc = 1.16 – 1.18 V under 500-fold concentrated solar radiation as well as values of photocurrent comparable with the best results of solar cells with epitaxial nGaAs are achieved. 相似文献
66.
R. Assenov V. A. Moshnikov D. A. Yaskov A. P. Andreev M. A. Bestaev 《Crystal Research and Technology》1987,22(9):1159-1163
By using the non-stationary thermal-probe method, investigations were carrieed out on the distribution of the coefficient of thermal electromotive force along the depth of monocrystals of lead telluride, subjected to isothermal saturating annealing in vapours of alloying compositions. The alloying composition consisted of powdered lead telluride, synthesized by the iodide method, and contained elevated concentration of the metallic component and iodine. The PbTe monocrystals were obtained from the vapour phase and had a natural cut. The results of the investigations testify to considerable changes in the concentration of the electrically active proper defects within the entire volume of the crystals, this being obviously connected with diffusion of vacancies from the crystal volume. 相似文献
67.
68.
Georgiy O. Kachkovskyi Oleg I. Kolodiazhnyi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(11):2238-2242
Two synthetic routes to phosphonic analogues of indoprofen, a nonsteroidal anti-inflammatory drug, were developed by the cyclization of aniline 2 (method A) and by the Arbuzov reaction of corresponding alkylchloride 3 with triethylphosphite (method B). 相似文献
69.
70.
V. B. Petkov E. V. Bugaev P. A. Klimai M. V. Andreev V. I. Volchenko G. V. Volchenko I. M. Dzaparova D. D. Dzhappuev A. N. Gaponenko Zh. Sh. Guliev N. F. Klimenko A. U. Kudzhaev A. V. Sergeev N. S. Khaerdinov A. B. Chernyaev A. F. Yanin 《Journal of Experimental and Theoretical Physics》2010,110(3):406-416
The energy spectra and temporal characteristics of high-energy gamma-ray bursts from evaporating primordial black holes have been calculated using various evaporation models. The currently existing theoretical uncertainties in the shape of the evaporated photon spectrum are discussed. The data from the Andyrchy and Carpet-2 arrays of the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences) obtained in the mode of detection of a single cosmic-ray component are used to search for cosmic gamma-ray bursts with a primary photon energy of about 8 GeV. New upper limits have been obtained for the number density of evaporating black holes in a local region of space with a characteristic size of ~10?3 pc for various evaporation models. 相似文献