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141.
O. V. Konstantinova A. V. Kuz’mov V. V. Skorokhod M. B. Shtern 《Powder Metallurgy and Metal Ceramics》2007,46(1-2):25-31
A theoretical method for determining the percolation limit and effective conductivity of composites based on polydisperse
mixtures of insulator and conductor powders is proposed. The effect of the particle size ratio between the insulator and conductor
on the percolation limit and effective conductivity is studied. Numerical simulation of the microstructure, effective properties,
and percolation limit in composites is discussed.
__________
Translated from Poroshkovaya Metallurgiya, Vol. 46, No. 1–2(453), pp. 31–40, 2007. 相似文献
142.
A method of processing complex signals in passive multi-element antenna arrays based on an analysis of the natural values of the correlation matrix of the signal is considered. By means of the method it is possible to substantially increase the output signal-to-noise ratio. An iterational process by means of which optimal estimators of both the signal and the amplitude-phase distribution may be obtained, is proposed. Theoretical estimators of the efficiency of the method are given. It is proved that, in terms of the efficiency, the approach considered in the article comes close to the technique of matched filtration. Results of statistical modeling that confirm the statistical results are presented. 相似文献
143.
M. S. Anan’evskii 《Automation and Remote Control》2007,68(8):1322-1332
A new approach to synthesize algorithms for selective control of the observables in quantum mechanical systems in the presence of additional constraints during the whole period of control is proposed. Analytic results of achieving the goal of control under some additional assumptions were obtained. It was demonstrated that the error in achieving the goal of control is proportionate to the error in prescribing the initial state of system and the error in realizing the control action. Numerical results for the problem of selective control for energy of hydrogen molecules (H2) with different isotopes are represented. The proposed algorithms are easy to design. 相似文献
144.
The possibility of determining the total α activity A(239,240Pu) of 239Pu + 240Pu according to the γ radiation of 103Ru and 106Ru is examined. The statistical properties of the experimental ratios of the activities ρ = A(106Ru)/A(103Ru) are investigated. The distribution of the experimental ratios is similar to the theoretical ratios for fuel and close
to a Gaussian distribution with average value 〈p〉 = 0.22 and standard deviation Δ ∼ 0.06. This ratio is used to obtain a relation
for estimating A(239,240Pu) from the γ activity A(103Ru). A theoretical analysis is made of the experimental data for the southern raions of Gomel oblast. It is shown that given
a good statistical sample of measurements of the γ activity of 103Ru it is possible to estimate the average value of the γ activity A(239,240Pu) and with probability 0.95 the interval of the possible values of this activity.
__________
Translated from Atomnaya énergiya, Vol. 103, No. 4, pp. 255–259, October, 2007. 相似文献
145.
E. O. Adamov B. A. Gabaraev I. Kh. Ganev A. V. Dzhalavyan A. V. Lopatkin E. V. Murav’ev V. V. Orlov 《Atomic Energy》2007,103(1):490-500
The results of investigations performed by specialists at Research and Design Institute of Electrical Technology together
with other enterprises, institutes, and organizations concerning the formulation of a strategy for the development of nuclear
power in Russia in the first half of the 21st century are presented. The individual stages of the work, key assumptions, ideas,
and recommendations, on which the strategy is based, the initiatives which the President of the Russian Federation advanced
at the millennium summit held at the United Nations, and the international INPRO project initiated by Russia are examined.
It is concluded that innovative development and a transition to building as quickly as possible nuclear power objects that
meet the requirements and demands of the new century are necessary.
__________
Translated from Atomnaya énergiya,Vol. 103, No. 1, pp. 5–15, July, 2007. 相似文献
146.
147.
148.
K.N. Yu H.H.W. Lee A.W.T. Wong Y.L. Law S.F.L. Cheung D. Nikezic F.M.F. Ng 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(1):271-278
A ray tracing method based on geometrical optics was used to study the tracks from alpha particles with different energies and with an incident angle of 50°. The transmission operation mode of the microscope is simulated. Considering the distribution of light intensities from the tracks, the mean and the 80% percentile gray levels from real experiments are proposed as quantitative variables to differentiate among tracks. The gray level properties for the same track for different exposures can vary to large extents. We introduce three variables, κ, λ and ε, to make empirical corrections. It is interesting to see that these coefficients are very consistent for the same alpha particle track despite the very different gray level properties. Gray level results have been obtained for tracks from alpha particles with 50° incident angle and different incident energies. However, the track depths cannot be predicted by any one of the coefficients κ, λ and ε. Multivariate analyses can help separate the tracks corresponding to different alpha energies. By using discriminant analysis with κ, λ and ε as independents, effectively all alpha energies can be determined with an accuracy of ±0.5 MeV. 相似文献
149.
L. A. Adamovich G. I. Grechko E. N. Gol’tsov A. M. Evdokimov V. A. Shishkin 《Atomic Energy》2007,103(1):537-542
The results of development work on an innovative low-capacity nuclear power plant (LCNPP) Uniterm together with substantiation
of the need for a technical design of a reactor system and the basic design of the power plant are presented. The results
of the work are used to determine the power range of the power generating unit where the main consumer qualities are guaranteed
to be attained. Economic assessments of the development and operation of a two-block LCNPP under conditions in Russia are
presented.
__________
Translated from Atomnaya énergiya,Vol. 103, No. 1, pp. 44–48, July, 2007. 相似文献
150.
A. S. Petukhov I. V. Khobta A. V. Ragulya A. V. Derevyanko A. I. Raichenko L. P. Isaeva A. M. Koval’chenko 《Powder Metallurgy and Metal Ceramics》2007,46(11-12):525-532
Powder mixtures based on titanium and its dihydrides are sintered by electric discharge in a certain current mode to produce TiN + TiB2 composites. It is established that the use of tetragonal titanium hydride as the starting material results in the complete synthesis leading to a TiN + TiB2 composite. The higher shrinkage rate results from the higher purity of titanium dihydride, which, in its turn, increases the partial pressure of hydrogen in the reaction area and the reaction rate. Tetragonal titanium hydride is more preferable than cubic hydride and metal titanium. The microstructure of alloys resulting from the sintering of hydride-based mixtures is more homogenous: it includes equiaxial grains with the mean size of about 1 µm. 相似文献