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91.
V. V. Yanilkin A. R. Mustafina A. S. Stepanov N. V. Nastapova G. R. Nasybullina A. Yu. Ziganshina S. E. Solovieva A. I. Konovalov 《Russian Journal of Electrochemistry》2011,47(10):1082-1090
The results of authors on designing electroswitchable supramolecular systems based on calix[4]arenes, calix[4]resorcinols,
and transition metal ions and complexes are summarized. We consider systems in which the switching is performed owing to electrochemical
reactions both of groups grafted to the macrocycle and bound substrates. Examples of electrochemically switchable luminescence
are given. 相似文献
92.
I. S. Edelman O. S. Ivanova V. N. Zabluda D. A. Velikanov V. I. Zaikovskii S. A. Stepanov E. A. Petrakovskaya R. D. Ivantsov 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(7):968-970
Germanate glasses doped simultaneously with Fe and rare earth elements Gd, Tb, Dy, and Ho in concentrations of several percent have been investigated. It is shown that the phase state of paramagnetic elements changes from isolated ions and small clusters in the initial glass to crystalline magnetic nanoparticles in the samples subjected to heat treatments. The field dependences of the magnetization of such samples are characterized by magnetic saturation in fields of about 1 kOe and large Faraday rotation in the near-IR region (up to 10 deg/cm in the range from 700 to 800 nm). 相似文献
93.
D. O. Sinitsyn V. Yu. Lunin A. N. Grum-Grzhimailo E. V. Gryzlova N. K. Balabaev N. L. Lunina T. E. Petrova K. B. Tereshkina E. G. Abdulnasyrov A. S. Stepanov Yu. F. Krupyanskii 《Russian Journal of Physical Chemistry B, Focus on Physics》2014,8(4):457-463
X-ray serial nanocrystallography is a new technique for determining the three-dimensional structure of biological macromolecules from data on the diffraction of ultrashort pulses generated by X-ray free-electron lasers. The maximum achievable resolution for a set of experimental data as a function of the sample sizes and parameters of the equipment is estimated based on simulations of the diffraction process with allowance for changes in the electronic structure of the atoms of the sample under the influence of X-rays. Estimates show that nanocrystallography greatly enhances the possibilities of X-ray analysis, reducing the requirements for the minimum permitted size of the crystals and enabling to explore poorly crystallizable molecular objects, such as many membrane proteins and complexes of macromolecules. 相似文献
94.
G. I. Greisukh E. A. Bezus D. A. Bykov E. G. Ezhov S. A. Stepanov 《Optics and Spectroscopy》2009,106(4):621-626
Optics and Spectroscopy - The method and results of studying the effect of relief depth on the attainable degree of reducing the spectral selectivity of two-layer diffraction structures based on... 相似文献
95.
J. I. Gorina G. A. Kaljuzhnaya M. V. Golubkov V. V. Rodin N. N. Sentjurina V. A. Stepanov S. G. Chernook O. E. Omel’yanovskii A. V. Sadakov 《Crystallography Reports》2010,55(3):525-530
Layered oxycarbonate Bi2Sr4Cu2CO3O8 single crystals have been obtained for the first time by free growth in closed vapor-phase cavities. The morphology, structure,
composition, and superconducting properties of these crystals have been investigated. 相似文献
96.
D. P. Kostomarov F. S. Zaitsev A. G. Shishkin S. V. Stepanov 《Moscow University Computational Mathematics and Cybernetics》2010,34(4):191-197
We consider problems of the visualization and automation of routine tasks that arise in the process of a computational experiment.
We describe ScopeShell, a state-of-the-art universal platform independent graphic interface for computational codes that includes
data visualization and the monitoring of calculations on distributed computing systems. We describe the concept behind ScopeShell,
along with the interface’s functionality and methods of application. The ScopeShell system is used to support computational
experiments in the field of controlled thermonuclear fusion. The system considerably increases the efficiency of research
requiring the application of voluminous computer codes. 相似文献
97.
A. V. Bokov V. M. Byakov L. A. Kulikov Yu. D. Perfiliev S. V. Stepanov 《Hyperfine Interactions》2017,238(1):95
Being the main cause of cancer, almost all chemical carcinogens are strong electrophiles, that is, they have a high affinity for the electron. We have shown that positron annihilation lifetime spectroscopy (PALS) is able to detect chemical carcinogens by their inhibition of positronium (Ps) formation in liquid media. Electrophilic carcinogens intercept thermalized track electrons, which are precursors of Ps, and as a result, when they are present Ps atom does not practically form. Available biophysical data seemingly indicate that frozen solutions model better an intracellular medium than the liquid ones. So it is reasonable to use emission Mössbauer spectroscopy (EMS) to detect chemical carcinogens, measuring the yield of 57Fe2+ions formed in reactions of Auger electrons and other secondary electrons they produced with 57Fe3+. These reactions are similar to the Ps formation process in the terminal part the positron track: e++ e? =>Ps. So EMS and PALS are complementary methods for detection of carcinogenic compounds. 相似文献
98.
Eugene Stepanov 《Proceedings of the American Mathematical Society》2002,130(2):433-442
It is shown that the relaxation of the integral functional involving argument deviations
in weak topology of a Lebesgue space (where and are standard measure spaces, the latter with nonatomic measure), coincides with its convexification whenever the matrix of measurable functions : satisfies the special condition, called unifiability, which can be regarded as collective nonergodicity or commensurability property, and is automatically satisfied only if . If, however, either 1$"> or 1$">, then it is shown that as opposed to the classical case without argument deviations, for nonunifiable function matrix one can always construct an integrand so that the functional itself is already weakly lower semicontinuous but not convex.
99.
A. A. Babin D. V. Kartashov A. M. Kiselev V. V. Lozhkarev A. M. Sergeev A. A. Solodov A. N. Stepanov 《JETP Letters》2002,76(9):548-552
The propagation of an intense (I≤106 W/cm2) femtosecond laser radiation with a duration of ~100 fs through gas-filled dielectric capillaries was studied. The radiation with a power up to 0.2 TW propagates along the paths up to 20 cm with a transmission efficiency of ~45%. The beam transverse structure at the output is close to the capillary fundamental mode under gas-ionization conditions. The transformation of pulse spectrum was studied as a function of input intensity. It is demonstrated experimentally that the pulse is compressed to a duration of ~30 fs due to the compensation of ionization-induced self-phase modulation in a linear dispersive element at the capillary output. 相似文献
100.
Gonnelli RS Daghero D Ummarino GA Stepanov VA Jun J Kazakov SM Karpinski J 《Physical review letters》2002,89(24):247004
We present the results of the first directional point-contact spectroscopy experiments in high-quality MgB2 single crystals. Because of the directionality of the current injection into the samples, the application of a magnetic field allowed us to separate the contributions of the sigma and pi bands to the total conductance of our point contacts. By using this technique, we were able to obtain the temperature dependency of each gap independent of the other. The consequent, strong reduction of the error on the value of the gap amplitude as a function of temperature allows a stricter test of the predictions of the two-band model for MgB2. 相似文献