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81.
A. N. Varaksin A. B. Sobolev A. Yu. Kuznetsov O. A. Keda 《Physics of the Solid State》1997,39(3):426-427
A model is proposed for the Lu2SiO5 crystal with cerium impurity, and the defect formation energy, ion relaxation energy, and the defect-induced changes of the
Madelung potentials are calculated. The calculations show substitution of the cerium ion for the lutetium ion in the Lu1 position to be energetically preferred.
Fiz. Tverd. Tela (St. Petersburg) 39, 491–492 (February 1997) 相似文献
82.
E. A. Krivandina Z. I. Zhmurova T. M. Glushkova M. M. Firsova A. P. Shtyrkova B. P. Sobolev 《Crystallography Reports》2003,48(5):878-882
Congruently melting compositions in the series of solid solutions R
1 − x
SrxF3 − x
(R = La-Nd with a defect structure of the tysonite type (LaF3) were found by the comparing the densities (determined by hydrostatic weighing) of the top and bottom parts of the single
crystals grown using the Bridgman method. Measurement errors are analyzed.
__________
Translated from Kristallografiya, Vol. 48, No. 5, 2003, pp. 940–944.
Original Russian Text Copyright ? 2003 by Krivandina, Zhmurova, Glushkova, Firsova, Shtyrkova, Sobolev.
Dedicated to the 60th Anniversary of the Shubnikov Institute of Crystallography of the Russian Academy of Sciences 相似文献
83.
N. S. Magomedova A. N. Sobolev M. P. Koroteev N. M. Pugashova V. K. Bel'skii É. E. Nifant'ev 《Journal of Structural Chemistry》1991,32(3):368-373
L. Ya. Karpov Scientific-Research Physical Chemistry Institute. Translated from Zhurnal Strukturnoi Khimii, Vol. 32, No. 3, pp. 67–73, May–June, 1991. 相似文献
84.
85.
A. Fonseca N.A. Sobolev E. Alves N.D. Zakharov A.A. Tonkikh 《Journal of luminescence》2006,121(2):417-420
In this work we studied the influence of high-energy proton irradiation on the optical and structural properties of an Si/Ge superlattice (SL) with embedded Ge quantum dots (QDs). The presence of QDs in the as-grown samples was established by transmission electron microscopy and photoluminescence (PL). The samples were irradiated with 2.0 MeV protons to fluences in the range 2×1012-2×1014 cm-2. The structural characterization made by X-ray reciprocal space mapping, X-ray reflection and Rutherford backscattering/channelling has shown no changes in the as-grown heterostructure due to the irradiation. In spite of the expected high concentration of nonradiative recombination centres caused by the proton-induced damage, the PL emission from the Ge dots has been observed even for the highest irradiation fluence. The studied QD-in-SL structure has shown an extraordinarily high radiation hardness when compared with previously studied QD heterostructures. 相似文献
86.
A. Frei Yu. Sobolev I. Altarev K. Eberhardt A. Gschrey E. Gutsmiedl R. Hackl G. Hampel F. J. Hartmann W. Heil J. V. Kratz Th. Lauer A. Liźon Aguilar A. R. Müller S. Paul Yu. Pokotilovski W. Schmid L. Tassini D. Tortorella N. Trautmann U. Trinks N. Wiehl 《The European Physical Journal A - Hadrons and Nuclei》2007,34(2):119-127
The production rates of ultracold neutrons (UCN) with a solid deuterium converter have been measured at the pulsed reactor
TRIGA Mainz. Exposed to a thermal neutron fluence of
n·cm^-2·pulse^-1, the number of detected very cold and ultracold neutrons ranges up to 200 000 at 7mol of solid deuterium
(sD2) in combination with a pre-moderator (mesitylene). About 50% of the measured neutrons can be assigned to UCN with energies
E of
where V
F(sD
2) = 105 neV and V
F(guide) = 190 neV are the Fermi potentials of the sD2 converter and our stainless steel neutron guides, respectively. Thermal cycling of solid deuterium, which was frozen out
from the gas phase, considerably improved the UCN yield, in particular at higher amounts of sD2. 相似文献
87.
S. S. Kutateladze V. E. Nakoryakov V. V. Sobolev I. R. Shreiber 《Journal of Applied Mechanics and Technical Physics》1974,15(5):638-642
Results are presented of a numerical solution of the Korteweg-de Vries-Burgers equation that describes the propagation and establishment process for a stationary structure to a shock wave in a gas-liquid medium. Data are obtained on the time for the establishment of a stationary structure of a shock wave, propagation velocity, and amplitude oscillations in the front of the shock wave. Experiments are discussed on the basis of the results obtained for the study of shock waves in a liquid containing gas bubbles. 相似文献
88.
V. G. Gasenko L. E. Kolesnikov V. V. Sobolev 《Journal of Applied Mechanics and Technical Physics》1973,14(6):827-831
The linear theory of the stability of the spherical shape of a cavity and the stability of its radial oscillations in a sound field are discussed. An equation is derived for the amplitudes of the spherical harmonics with allowance for surface tension, viscosity, and compressibility of the surrounding liquid in the Herring-Flynn approximation. The radial pulsation stability is analyzed in the same approximation. The equations derived in the article are subjected to numerical analysis.Translated from Zhurnal Prikladnoi Mekhaniki i Tekhnicheskoi Fiziki, No. 6, pp. 109–114, November–December, 1973. 相似文献
89.
The design of efficient systems for the targeted delivery of nucleic acids into cells is a rapidly developing area of polymer chemistry, molecular biology, and medicine. Complexes between DNA or RNA polyanions and various polycations, which are usually called polyplexes, hold promise as such delivery systems. Polyethylenimines (PEIs) and their derivatives are often used in research for the preparation of such complexes with plasmid DNA, oligonucleotides, and small RNA. Polyplex nanoparticles are employed for the delivery of genetic material into cells in culture and for the development of methods for the treatment of genetic and cancer diseases. The properties of polyplexes depend on the size, dispersity, and hydrophilicity of the used PEI or its derivatives and the ratio of polymers in the complex, which are responsible for the size, surface charge, and hydrophilicity of the resulting nanoparticles. The efficiency of polyplexes is determined by their ability to interact with components of biological systems on the surface and inside the cells, as well as with the blood vascular walls and the extracellular matrix during systemic in vivo use. 相似文献
90.
A procedure has been proposed for measuring the surface potential of hollow-fiber membranes by the streaming-potential method under the conditions of a tangential flow of a solution. The zeta-potential and surface charge of nanofiltration hollow-fiber polyacrylonitrile membranes have been measured. The measurements have been performed for membranes with different porosities, which were obtained by partial drying of initial humid membranes. The porosity has been determined from the electrical conductivity of a membrane. An equation has been proposed for calculating the charge transfer by a solution flow in a porous layer. It has been shown that the use of the proposed equation makes it possible to obtain more correct values of the membrane surface potential. 相似文献