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31.
A. A. Andronov I. A. Grishin V. A. Gur’ev V. V. Orekhovskii A. P. Savikin 《Technical Physics Letters》1998,24(5):365-366
In fluorozirconate glasses the luminescence yield of Er
2
3+
ions on the 4
I
13/2–4
I
15/2 lasing transition was increased more than tenfold by additional doping with Yb3+ and Tb3+ ions.
Pis’ma Zh. Tekh. Fiz. 24, 81–85 (May 12, 1998) 相似文献
32.
Yu. M. Shernyakov A. Yu. Egorov B. V. Volovik A. E. Zhukov A. R. Kovsh A. V. Lunev N. N. Ledentsov M. V. Maksimov A. V. Sakharov V. M. Ustinov Zhen Zhao P. S. Kop’ev Zh. I. Alferov D. Bimberg 《Technical Physics Letters》1998,24(5):351-353
Continuous-wave lasing has been demonstrated in a vertically coupled quantum-dot laser with a high output power (1.5 W) at
room temperature. It was shown that anisotropy of the quantum dot profile leads to anisotropy of the laser operating characteristics.
Pis’ma Zh. Tekh. Fiz. 24, 50–55 (May 12, 1998) 相似文献
33.
Rapid development of the cluster multiprocessor computer systems allows one to pose to the designers of the computer-graphical systems the problem of organization of graphical information enabling efficient use of the parallel algorithms. Consideration was given to the use of the dichotomous principle of binary construction of a numerical sequence for successive indexing of the elements of a multidimensional array in the problems of recursive decomposition of the multidimensional space. This principle was used to advantage in recursive construction of the voxel graphical information used in the program accelerators of graphical processing based on parallelization of the algorithm and partial sorting of the graphical output flow in terms of the recursion depth. 相似文献
34.
Summary The synthesis is reported of copolymers of styrene with methacrylic acid and of methyl methacrylate with methacrylic acid by radical copolymerization, of copolymers of methyl methacrylate with methacrylic acid by partial alkaline hydrolysis of poly(methyl methacrylate), and of block copolymers of styrene with methacrylic acid. Modified titration curves of all these copolymers were recorded in water and water-ethanol solutions. In a solution containing 50 mass.% ethanol, only small differences could be observed between the potentiometric behaviour of the individual copolymers and polymethacrylic acid. Also, there were no essential differences in any of the solvents used between the potentiometric behaviour of block copolymers of styrene with methacrylic acid, on the one hand, and polymethacrylic acid, on the other. On the contrary, maxima and minima were always observed on the modified titration curves of statistical copolymers with a higher content of the hydrophobic comonomer in solutions with a high water content. Thus, using the modified titration curves, it is possible to decide whether a given copolymer is of the block or statistical type. 相似文献
35.
V.?P.?BessmeltsevEmail author M.?V.?Maksimov V.?V.?Vileiko N.?V.?Goloshevskii V.?S.?Terent’ev 《Optoelectronics, Instrumentation and Data Processing》2018,54(6):531-537
Implementation of a laser scanning confocal microscope is described, where the specimen is scanned by an array of illuminating beams, which significantly increases the velocity of object image construction. The array formation is provided by using a diffractive optical element. Scanning by the array of laser beams over the specimen is performed by galvanometric scanners with moving refractive plane-parallel plates. Owing to application of such a scanning device, the beams in the illuminating channel and the signal beams in the receiving channel pass through one motionless array of confocal diaphragms; as a result, the scanning beams in the specimen plane and the signal beams in the plane of the photodetector matrix can be used without an additional synchronized pair of scanners. The proposed confocal microscope can be applied in problems that require a fast response. 相似文献
36.
Agroskin V. Ya. Bravyi B. G. Vasil’ev G. K. Gur’ev V. I. Kashtanov S. A. Makarov E. F. Sotnichenko S. A. Chernyshev Yu. A. 《Combustion, Explosion, and Shock Waves》2021,57(2):138-149
Combustion, Explosion, and Shock Waves - The ignition of methane–air mixtures with additives of ClF5, ClF3, OF2, and H2O2 (additive content in the mixtures $$\le$$ 1%) is studied by... 相似文献
37.
Meerov D. B. Monogarov K. A. Muravyev N. V. Fomenkov I. V. Vasil’ev A. L. Shishov N. I. Pivkina A. N. 《Combustion, Explosion, and Shock Waves》2021,57(5):547-558
Combustion, Explosion, and Shock Waves - The effect of polymer binders on the thermal behavior, combustion, and composition of condensed gasification products of model boron-containing compositions... 相似文献
38.
KS Makarova IuI Vul'f IA Seledtsov VA Ratner 《Canadian Metallurgical Quarterly》1995,31(12):1614-1629
Transposons of gypsy group are assigned to LTR-containing retrotransposons present in the genomes of invertebrates, fungi, and plants. In this work, a theoretical analysis of the potential products of ORFs of these retrotranposons was conducted. Alignments were obtained and trees of similarity were constructed for domains of the POL region. On the basis of the obtained data, two hypothetically monophyletic subgroups of transposons were distinguished within the framework of the gypsy group, settling the genomes of taxonomically related organisms (the subgroup of "true" gypsy of insects and the subgroup of gypsy-like transposons of plants and fungi). A number of peculiarities of the topology of these trees hypothetically indicate cases of genetic conversion and recombination of domains accompanying the evolution of this group. The amino acid substitution fixation rate was evaluated on the basis of comparison of sequences of the protein products of ORFs. Estimates of the time of divergence of subgroups of gypsy-group transposons are significantly less than estimates of the times of divergence of their host species. One explanation for this discrepancy might be the hypothesis of settlement by transposons of the genomes of isolated host species. 相似文献
39.
S. V. Zavarzin A. V. Anan’ev A. I. Fadeev M. Yu. Kalenova I. V. Kuznetsov 《Radiochemistry》2017,59(5):448-452
Electrochemical properties of the intermetallic compound URh3 in 0.5–8 M HNO3 solutions were studied by linear voltammetry. The electrochemical characteristics of URh3 in nitric acid solution were determined for the first time using the Tafel equation. URh3 is highly resistant to both chemical and anodic dissolution, which is due to formation of passive films on the electrode surface. All the anodic oxidation processes observed on the electrode led to secondary passivation of the alloy and not to its dissolution. The conclusions based on the electrochemical data were confirmed by experiments in 8 M HNO3. 相似文献
40.
N.?M.?BarbinEmail author A.?M.?Kobelev D.?I.?Terent’ev S.?G.?Alekseev 《Radiochemistry》2017,59(5):507-511
The behavior of actinides (U, Am, Pu) in the course of combustion of radioactive graphite in steam was studied by thermodynamic modeling. Thermodynamic modeling was performed using TERRA program in the temperature interval from 373 to 3273 K to determine the possible composition of volatile actinide species formed in the course of graphite utilization by heating in steam. The modeling shows that the actinides at high temperatures are present in the following forms: U, as UO3 and UO2 vapors and as UO3 – and UO2 + ions; Am, as Am vapor; and Pu, as PuO2 and PuO vapors and as ionized PuO+. The main reactions within separate phases and at the interface were revealed, and their equilibrium constants were determined. 相似文献