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51.
The resonance wavelength of the fiber Bragg gratings (FBGs) is tuned using two methods. Tunable FBGs are used as the selecting elements in the cavities of tunable lasers. An ytterbium-doped fiber laser with a wavelength tuning range of 1063–1108 nm and an output power of 6 W, a Raman fiber laser with a wavelength tuning range of 1252–1303 nm and an output power of 3 W, and an erbium-doped fiber laser with a wavelength tuning range of 1530–1580 nm are realized, and their characteristics are studied. 相似文献
52.
D. M. Podorozhnyi V. L. Bulatov N. V. Baranova A. V. Vlasov A. G. Voronin N. N. Egorov S. A. Golubkov V. M. Grebenyuk D. E. Karmanov M. G. Korolev N. A. Korotkova Z. V. Krumshtein E. G. Lyannoy M. M. Merkin A. Yu. Pavlov A. Yu. Pakhomov A. V. Romanov A. B. Sadovskii L. G. Sveshnikova L. G. Tkachev A. V. Tkachenko A. Turundaevskiy 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(4):500-502
The main purpose of the NUCLEON experiment is direct measurements of the energy spectra of cosmic rays in the range 1011–1015 eV with the use of the lightweight facility during a prolonged orbital flight. The energy is determined using a technique based on the measurement of the spatial density of secondary particles produced in the initial event of inelastic interaction. The schematic diagram of the NUCLEON facility, the current status of the project, the results of testing the prototype, and plans are presented. 相似文献
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Scientific-Research Institute of Nuclear Physics at the Moscow State University. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 78, No. 3, pp. 323–329, March, 1989. 相似文献
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The distinctive features of the formation of the catalyticity of materials with respect to atom recombination on the material surface are investigated for mixtures of different high-temperature gases under conditions of hypersonic atmospheric flight or bench setups. It is shown that in general the catalyticity constants (heterogenous recombination probabilities) of individual components determined experimentally in dissociated flows of “pure” gases are improperly used for calculating the heat fluxes to material surfaces in multicomponent gas flows, owing to differences in the occupation of the surface by atoms in pure gases and mixtures. This effect must be taken into account in interpreting the experimental data which so far have been the only source of information on material catalyticity in gas mixtures. Otherwise, the results of calculations of the heat transfer to hypersonic flight vehicles could turn out to be invalid. Examples of the possible effect of ignoring this factor on the calculated heat fluxes are presented. 相似文献
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M. G. Voronkov A. V. Vlasov N. N. Vlasova 《Russian Journal of Organic Chemistry》2010,46(12):1838-1842
Reactions of acetyl iodide with pyridine at room temperature and with quinoline both at 20–25°C and on cooling to −50°C involve
dehydrohalogenation of acetyl iodide with formation of ketene and pyridinium or quinolinium iodides. The reaction of acetyl
iodide with pyridine at −5 to −50°C led to the formation of N-acetylpyridinium iodide. Benzoyl iodide reacted with both pyridine and quinoline at both −50°C and at 20–25°C to form stable
N-benzoylpyridinium and N-benzoylquinolinium iodides. The reaction of pyrrole with acetyl iodide under analogous conditions was accompanied by polymerization. 相似文献
60.
A. P. Ivanov L. N. Kotov V. S. Vlasov F. F. Asadullin S. M. Poleshchikov V. V. Koledov V. I. Shcheglov V. G. Shavrov 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(2):187-189
The occurrence of translational motion in the domain system in a ferrite plate under harmonic parametric action is investigated.
The domain dynamics is described on the basis of the numerical solution of differential equations for a system of connected
oscillators. Transition scenarios from oscillatory to translational motion are described, depending on the changes in the
nonlinearity constant and damping parameter for various numbers of oscillators. 相似文献