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Tkachenko V. A. Yaroshevich A. S. Kvon Z. D. Tkachenko O. A. Rodyakina E. E. Latyshev A. V. 《JETP Letters》2021,114(2):110-115
JETP Letters - The low-frequency microwave photoconductance of a short (100 nm) quantum point contact based on a high-mobility two-dimensional electron gas in the frequency range of 2–3 GHz... 相似文献
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S. F. Boulyga A. I. Kievitskaja M. K. Kievets E. M. Lomonosova I. V. Zhuk O. I. Yaroshevich V. P. Perelygin R. Petrova R. Brandt P. Vater 《Radiation measurements》1999,31(1-6):191-196
Nuclear track radiography was applied to identify aerosol “hot” particles which contain elements of nuclear fuel and fallout after Chernobyl NPP accident. For the determination of the content of transuranium elements in radioactive aerosols the measurement of the -activity of “hot” particles by SSNTD was used in this work, as well as radiography of fission fragments formed as a result of the reactions (n,f) and (γ,f) in the irradiation of aerosol filters by thermal neutrons and high energy gamma quanta. The technique allowed the sizes and alpha-activity of “hot” particles to be determined without extracting them from the filter, as well as the determination of the uranium content and its enrichment by 235U, 239Pu and 241Pu isotopes. Sensitivity of determination of alpha activity by fission method is 5×10−6 Bq per particle. The software for the system of image analysis was created. It ensured the identification of track clusters on an optical image of the SSNTD surface obtained through a video camera and the determination of size and activity of “hot” particles. 相似文献
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S. F. Boulyga N. Erdmann H. Funk M. K. Kievets E. M. Lomonosova A. Mansel N. Trautmann O. I. Yaroshevich I. V. Zhuk 《Radiation measurements》1997,28(1-6):349-352
The knowledge of the isotopic composition of man-made transuranium elements (TUE) in the environmental samples is of great interest because, on the basis of these data, statements about the origin of the TUE can be made. One of the most radiotoxic elements released during reactor accidents and nuclear weapons tests was plutonium with the alpha emitters 238Pu, 239Pu, 240Pu, 242Pu and the beta-emitter 241Pu which decays into 241Am. The determination of plutonium in “hot” particles from the Chernobyl reactor was accomplished by means of solid state nuclear track detectors registering the alpha particles and by alpha spectroscopy after chemical treatment. Furthermore, in order to perform a complete analysis of the isotopic composition one of the “hot” particles has been investigated by resonance ionization mass spectrometry which possesses an excellent sensitivity and a good isotopic resolution. 相似文献
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V. L. Al’perovich N. T. Moshegov V. V. Popov A. S. Terekhov V. A. Tkachenko A. I. Toropov A. S. Yaroshevich 《Physics of the Solid State》1997,39(11):1864-1868
Photocurrent spectroscopy is used to study the nature of the roughness of heteroboundaries in (AlAs)m/(GaAs)n short-period superlattices (m=3−5, n=10−13) grown by molecularbeam epitaxy. The formation of minibands broadens the optical spectra of superlattices in comparison
with isolated quantum wells; therefore to analyze the degree of perfection of the boundaries we used the decay of the minibands
into a series of discrete Wannier-Stark levels in an electric field parallel to the superlattice axis. Exciton lines were
observed in the photocurrent spectra in an electric field corresponding to direct and indirect (in space) transitions between
the Wannier-Stark levels. Comparison of experimental data with calculation indicates that even in the better structures, in
addition to monotonic variation of the thickness of the layers over area, roughnesses in the heteroboundaries one monolayer
in height are present with characteristic lateral dimension not exceeding 10 nm.
Fiz. Tverd. Tela (St. Petersburg) 39, 2085–2089 (November 1997) 相似文献
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I. V. Zhuk E. M. Lomonosova O. I. Yaroshevich M. K. Kievetz S. F. Boulyga I. A. Tzekhanovich Yu. I. Bondar 《Radiation measurements》1995,25(1-4):385-387
An investigation of vertical distribution of alpha-emitting nuclides for various types of soils using solid state nuclear track detectors (SSNTD) has been carried out. As SSNTD the DNC-film was used. Experimental system for measurement of total alpha activity in the samples of soils, including devices and equipment for selection of probes, exposition, chemical etching of detectors, automated accounting of tracks has been developed. The method of determination of specific activity of alpha emitting nuclides has been created. A comparison results of measurements with the method pointed out and radiochemical method as well as x-y-spectrometry method has been carried out. 相似文献
7.
Erratum to:Study of GroEL Conformational Mobility by Cryo-Electron Microscopy and Molecular Dynamics
Panina I. S. Mamchur A. A. Yaroshevich I. A. Zlenko D. V. Pichkur E. B. Kudryavtseva S. S. Muronetz V. I. Sokolova O. S. Stanishneva-Konovalova T. B. 《Crystallography Reports》2022,67(2):310-310
Crystallography Reports - An Erratum to this paper has been published: https://doi.org/10.1134/S1063774521340058 相似文献
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A. A. Pakhnevich V. V. Bakin A. V. Yaz’kov G. É. Shaibler S. V. Shevelev O. E. Tereshchenko A. S. Yaroshevich A. S. Terekhov 《JETP Letters》2004,79(10):479-483
Energy distributions of photoelectrons emitted into vacuum from the valence band and the localized states in the energy gap of p-GaN(Cs, O) with effective negative electron affinity were studied. It is shown that the photothermal electron excitation from the localized states lying below the Fermi level in the energy gap of p-GaN(Cs, O) is the dominant photoemission mechanism at the low-energy photoemission threshold. 相似文献
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V. L. Al'perovich A. S. Terekhov V. A. Tkachenko O. A. Tkachenko N. T. Moshegov A. I. Toropov A. S. Yaroshevich 《Physics of the Solid State》1999,41(1):143-147
The photocurrent was measured as a function of the external electric field in short-period AlAs/GaAs superlattices for various
photon energies. Transport resonances, whose positions do not depend on the photon energy, were observed in these dependences
together with optical resonances due to interband transitions in Wannier-Stark levels. It is shown that the transport resonances
are due to tunneling of photoelectrons from the p-GaAs contact region into the first level in GaAs wells located 2–5 lattice periods from the contact layer.
Fiz. Tverd. Tela (St. Petersburg) 41, 159–164 (January 1999) 相似文献