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91.
92.
A. V. Grachev S. A. Siling O. Yu. Tsyganova S. V. Shamshin V. I. Yuzhakov I. G. Abramov V. V. Plakhtinskii 《Journal of Applied Spectroscopy》2000,67(3):461-466
Results of the spectral-luminescence investigation of solutions of new heterocyclic compounds are given. The relationship
between the structure of the heterocyclic compounds and their spectral-luminescence characteristics is analyzed. The concentrations
are established beginning with which the concentration quenching of luminescence occurs. Double luminescence manifested by
certain compounds is related to their existence in the form of isomers.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 67, No. 3, pp. 336–339, May–June, 2000. 相似文献
93.
94.
Yuli YA. Gotlib 《Macromolecular Symposia》1999,146(1):81-87
The dynamic network model taken into account the friction relative to incompressible effective viscous medium (EVM), the hydrodynamic interactions of a network with the EVM, and the interchain friction is considered. Two collective network relaxation spectra (RS) arise. The first RS corresponds to the network motion relative to immobile EVM, the EVM does not take part in this motion. The second RS includes the combined viscous motion of the network and EVM because of long-range hydrodynamic interactions. This RS is finite and narrow for infinitely large network. The symmetry of this motion is in concordance with that of incompressible EVM. The existence of interchain friction leads to the narrowing of both types of relaxation spectra. 相似文献
95.
V. S. Abramov 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(5):579-586
The stochastic behavior of the strain fields of coupled systems (a fractal layer, a nanotrap, and quantum dots in a fractal multilayer nanosystem) is studied theoretically and numerically. As the semiaxes of a quantum dot shorten, the amplitude of the primary peak falls, a bump emerges on it, and the region of stochastic behavior shrinks in size. As the semiaxes grow, a broadened peak with a stochastic base in the background (a halo-type signal) forms. 相似文献
96.
The results of ultrasonic action to the substances have been presented. It is examined, the correlation between the electrical
parameters of ultrasonic equipment and acoustic performances of the ultrasonic field in treating the medium, the efficiency
of ultrasonic technological facility, and the peculiarities of oscillations introduced into the load under cavitation development.
The correlation between the acoustic powers of oscillations securing the needed level of cavitation and desired technological
effect, and the electrical parameters of the ultrasonic facility, first of all, the power, is established. The peculiarities
of cavitation development in liquids with different physical-chemical properties (including the molten low-melting metals)
have been studied, and the acoustic power of oscillations introduced into the load under input variation of electric power
to the generator has been also estimated. 相似文献
97.
Rafail V. Abramov 《Journal of computational physics》2009,228(1):96-108
In a recent paper we developed a new algorithm for the moment-constrained maximum entropy problem in a multidimensional setting, using a multidimensional orthogonal polynomial basis in the dual space of Lagrange multipliers to achieve numerical stability and rapid convergence of the Newton iterations. Here we introduce two new improvements for the existing algorithm, adding significant computational speedup in situations with many moment constraints, where the original algorithm is known to converge slowly. The first improvement is the use of the BFGS iterations to progress between successive polynomial reorthogonalizations rather than single Newton steps, typically reducing the total number of computationally expensive polynomial reorthogonalizations for the same maximum entropy problem. The second improvement is a constraint rescaling, aimed to reduce relative difference in the order of magnitude between different moment constraints, improving numerical stability of iterations due to reduced sensitivity of different constraints to changes in Lagrange multipliers. We observe that these two improvements can yield an average wall clock time speedup of 5–6 times compared to the original algorithm. 相似文献
98.
S. V. Ermolaev B. L. Zhuikov V. M. Kokhanyuk A. A. Abramov N. R. Togaeva S. V. Khamianov S. C. Srivastava 《Journal of Radioanalytical and Nuclear Chemistry》2009,280(2):319-324
A method for production of no-carrier-added 117mSn (NCA 117mSn) has been developed. It includes proton irradiation of thick antimony targets and chemical recovery of 117mSn by extraction of Sb with dibutyl ether and chromatographic purification on silica gel column. The method provides production
of curie amounts of 117mSn with specific activity about 1000 Ci/g and high radionuclidic purity. 相似文献
99.
设k,n1和n2是3个正整数,G=(V1,V2;E)是一个二分图,使得|V1|=n1,|V2|=n2,其中n1≥2k+1,n2≥2k+1并且n1-n2≤1.如果对任意不相邻的x∈V1和y∈V2,都有d(x)+d(y)≥2k+2,则G包含k个相互独立的圈.以上结果部分地回答了Enomoto提出的关于二分图有独立圈的问题. 相似文献
100.
A. V. Virovets A. L. Gushchin P. A. Abramov N. I. Alferova M. N. Sokolov V. P. Fedin 《Journal of Structural Chemistry》2006,47(2):326-338
Various synthetic approaches are used to obtain new triangular complexes with rare cluster nuclei M3Te7 4+ (M = Mo, W), as well as with partial substitution for chalcogen W3Te3.8Se 3.2 4+ . The crystalline structure has been identified for K5{[Mo3Te7(CN)6]2I}·2.5H2O (I), K3{[Mo3Te7(CN)6]SeCN}·3.25H2O (II), Cs2K{ [W3Te7(CN)6]Br0.8Cl0.2}·2.5H2O (III), Cs3{ [W3Te7(CN)6]Br}·2H2O (IV), Cs1.59K1.41{[W3Te3.8Se3.2× ×(CN)6]Br}·1,5H2O (V), [W3Te7((EtO)2PS2)3]Br (VI). The compounds are characterized by IR methods and electronic spectroscopy, electrospray-mass-spectrometry. The crystalline structure of this class of compounds is analyzed. Specific non-valence interactions in these systems are considered in detail. 相似文献