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V. G. Bespalov V. N. Krylov S. E. Putilin D. I. Stasel’ko 《Optics and Spectroscopy》2002,93(1):148-152
Generation of a coherent electromagnetic radiation in the far IR (THz) spectral range upon excitation of a semiconductor InAs crystal by 70-fs Ti: sapphire laser pulses is studied. The effect of a magnetic field of different orientation on generation in the submillimeter-wavelength range is analyzed. Placing the crystal into the magnetic field of an optimized permanent magnet with a strength of 5 kOe aligned along the surface of the semiconductor increased the power of generated radiation by a factor of six compared with that in the absence of the field. For the average pump-laser output power of 150 mW and repetition rate of 80 MHz, the average power of the THz radiation reached 100 nW. For detection of ultrashort pulses of the THz radiation, we used, for the first time, a highly sensitive uncooled optoacoustic detector, which detected signals with a power lower than 1 nW. 相似文献
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V. G. Domelunksen I. R. Krylov G. A. Polyanskaya M. A. Tsygankov 《Optics and Spectroscopy》2004,97(1):136-140
An interference method for measuring certain parameters of a substance in the vicinity of the critical state is proposed. The essence of the method is to decipher the interference pattern arising upon grazing incidence of a laser beam on a curved liquid-vapor interface. The deciphering allows one to determine the difference between the refractive indices of the two phases and the scaling factor of the wetting meniscus shape. This, in turn, makes it possible to calculate the critical exponents for the temperature dependences of the surface tension and the difference in the densities of the two phases. The ratio of these critical exponents for xenon, measured in the paper, is 3.81±0.03. 相似文献
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Copolymers of pyrrole and 3-phenylthiophene were obtained by electrochemical polymerization. These copolymers were identified by IR and electronic spectroscopy. The composition, electrochemical properties, and spectral indices of the copolymers depend on the potential for deposition from the monomer mixture and the ratio of pyrrole to 3-phenylthiophene.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 29, No. 2, pp. 159–164, March–April, 1993.The authors express their gratitude Academician V. D. Pokhodenko of the Academy of Sciences of Ukraine for his advice and comments in a discussion of this work. 相似文献
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V. D. Pokhodenko V. A. Krylov Ya. I. Kurys' 《Theoretical and Experimental Chemistry》1996,31(6):301-304
We propose a new approach to obtaining composites of the intercalation type based on polyaniline and V2O5. We have determined the characteristics of these composites using x-ray diffraction, IR spectroscopy, and EPR. We show that the compounds obtained exhibit stable redox properties in aqueous and aprotic electrolytes.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 31, No. 6, pp. 361–364, November–December, 1995.We would like to express our thanks to V. G. II'in for help in carrying out the x-ray phase investigations. This work was made possible with the partial support of the International Science Foundation (grant N U6B000). 相似文献
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V. A. Krylov O. Yu. Chernova Yu. M. Salganskii L. S. Malygina A. P. Kotkov 《Journal of Analytical Chemistry》2003,58(8):750-755
It is shown that the results of determining methane in high-purity arsine by reaction gas chromatography can be overestimated by more than two orders of magnitude. This overestimation is caused by the formation of methane as a side product of the reaction. Cryogenic preconcentration at the injection stage is proposed to improve the accuracy of determination of methane, and the cryofocusing of impurity hydrocarbons is proposed to improve separation. Detection limits of (3–10) × 10–6 vol % are achieved for C1–C5 hydrocarbons. 相似文献
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Krylov I. O. Lugovskaya I. G. Anufrieva S. I. Krylova A. V. 《Russian Journal of Applied Chemistry》2003,76(8):1234-1237
The chemical composition, specific surface area, and pore structure of a schungite sorbent were studied as influenced by the conditions of thermal treatment. 相似文献