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S. A. Kazantsev N. M. Firstova L. K. Kashapova A. V. Bulatov A. G. Petrashen' 《Russian Physics Journal》1998,41(12):1258-1262
Polarization data are given for three whiskers recorded with the large solar vacuum telescope at the Baikal Observatory, Institute
of Solar-Terrestrial Physics, Russian Academy of Sciences. The observed degree of polarization varies from 2 to 13%. The direction
of the polarization plane for the mediumintensity whisker was tangential, while that for the weakest one was radial. The brightest
whisker had the polarization plane direction close to radial at the center of the line but tangential at the flanks. It is
assumed that the polarization is due to impact excitation of a hydrogen-atom ensemble in the solar chromosphere by an electron
beam, and estimates are made of the beam energy.
St. Petersburg Fine Mechanics and Optics Institute, St. Petersburg. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii,
Fizika, Vol. 41, No. 12, pp. 85–89, December 1998. 相似文献
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A. A. Firstova E. R. Kofanov G. G. Krasovskaya A. S. Danilova 《Russian Chemical Bulletin》2017,66(5):867-869
A synthesis new aryl alicyclic tricarboxylic acids bearing two carboxyl groups at either cyclohexane or norbornane fragment and one carboxyl group at the benzene ring was devel-oped. Tricarboxylic acids of this type are promising monomers for the synthesis of hetero-cyclic polymers. 相似文献
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Bufetov IA Melkumov MA Firstov SV Shubin AV Semenov SL Vel'miskin VV Levchenko AE Firstova EG Dianov EM 《Optics letters》2011,36(2):166-168
Luminescence emission and excitation spectra of bismuth-doped silica optical fibers free of other dopants have been obtained to construct an emission-excitation map in a wide wavelength range of 400-1600 nm. The main low-lying energy levels of the bismuth active centers in such fibers have been determined. For the first time (to our knowledge), optical gain and lasing have been obtained in such fibers. A gain of 8 dB has been achieved with a pump power of 340 mW, and a cw fiber laser emitting at 1460 nm with an output power of 40 mW and an efficiency of ≈3% has been created. 相似文献
4.
Dr. Vincent Diemer Olga Firstova Dr. Vangelis Agouridas Dr. Oleg Melnyk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(16):e202104229
The native chemical ligation reaction of peptide thioesters with cysteinyl peptides is a pivotal chemical process in the production of native or modified peptides and proteins, and well beyond in the preparation of various biomolecule analogs and materials. To benefit from this reaction at its fullest and to access all the possible applications, the experimentalist needs to know the factors affecting its rate and how to control it. This concept article presents the fundamental principles underlying the rate of the native chemical ligation and its homogeneous catalysis by nucleophiles. It has been prepared to serve as a quick guide in the search for an appropriate catalyst. 相似文献
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