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51.
S. M. Arakelian A. V. Osipov I. O. Skryabin Tran Dinh Phong Nguyen Tran Thuath 《Bulletin of the Russian Academy of Sciences: Physics》2017,81(12):1416-1419
The current-voltage relationships of deposited structures are measured for cluster structures consisting of nanoparticles of lead telluride. Variation in the value of the tunnel current is shown. Optimum conditions for the possible emergence of quantum-hopping conductivity due to carrier tunneling (the characteristic sizes of the nanoclusters and the distances between them) are determined. 相似文献
52.
A sharp almost sure bound is derived for limit points of average sum of weakly dependent random variables, which ensures strong laws of large numbers for and -mixing random variables, without assumptions on rate of tending to zero of and -mixing parameters n and n. 相似文献
53.
Fundamental equations of the theory of spatially reinforced media with a matrix reinforced by spherical particles are proposed on the basis of a linearly reinforced layer and tl.e hypothesis of a longitudinal state. For an arbitrary orientation of the fibers, the generalized elasticity equation for composites was found to contain 21 elastic constants and approximate formulas were derived for their determination.Presented at the Ninth International Conference on the Mechanics of Composite Materials, Riga. Latvia (October, 1995).Communication 1. see preceding article.A. A. Blagonravov Institute of Mechanical Engineering. Russian Academy of Sciences, Moscow. Russian. Translated from Mekhanika Kompozitnykh Materialov, Vol. 32, No. 3, pp. 306–316, May–June, 1996. 相似文献
54.
Simultaneous analyses of inclusive and semi-inclusive reactionns in neutrino-nucleon collisions and elastic neutrino-proton scattering uniquely determine the neutral-current couplings between neutrinos and hadrons up to a two-fold “vector-axial-vector ambiguity”. One of the preferred solutions coincides with the Salam-Weinberg model within errors while the other solution, also compatible with SU(2) ? U(1) models with the simplest Higgs mechanism, may be helpful in understanding the bismuth puzzle. 相似文献
55.
A precise and rapid transient diffusion experiment has been developed to measure the diffusive permeability of hollow fibers. In this experiment a sealed hollow fiber containing a radioactive solute is exposed sequentially to several well-stirred solute-free reservoirs. This method was used to measure the diffusive permeability of collagen and Cuprophan hollow fibers in an isotonic saline solution for a spectrum of 14C labelled solutes: urea, sucrose and polyethylene glycol (PEG). To study the effect of environment on membrane permeability, collagen membranes were investigated with urea, sucrose and tritiated water in the following solutions with varying ionic strength and hydrogen ion concentration: pH2 HCl, distilled water and pH2 HCl with 0.8 M NaCl.In each environment, the membranes showed the expected decreases in diffusive permeaability with increasing molecular weight. Collagen membranes ranged from 4 (urea) to 40 (PEG) times the permeability of Cuprophan membranes. The Cuprophan data are consistent with results obtained elsewhere using scaled-down dialyzers. In response to environmental changes, the diffusive permeability of collagen membranes changed overall by a factor of 3 with the following rank: pH 2 HCl > distilled water > pH2 HCl and 0.8 M NaCl. The hydraulic permeability of these membranes changed by a factor of 2 but in a different order pH2 HCl > pH2 HCl and 0.8 M NaCl > distilled water. These permeability changes can be explained in terms of the known environmental dependence for the structure of collagen membranes and have been shown to be consistent with trends predicted by simple transport models. 相似文献
56.
57.
We summarize here some theoretical results for fictitious gas regularization of compressible flow and give error estimates for the finite element approximation to the regularized problem. 相似文献
58.
In this note, we prove that if N is a compact totally geodesic submanifold of a complete Riemannian manifold M, g whose sectional curvature K satisfies the relation K ≥ k > 0, then
for any point m ∈ M. In the case where dim M = 2, the Gaussian curvature K satisfies the relation K ≥ k ≥ 0, and γ is of length l, we get Vol (M, g) ≤
if k ≠ 0 and Vol (M, g ≤ 2ldiam (M) if k = 0.__________Published in Ukrains’kyi Matematychnyi Zhurnal, Vol. 56, No. 11, pp. 1576–1583, November, 2004. 相似文献
59.
Ab initio materials design for transparent-conducting-oxide-based new-functional materials 总被引:1,自引:0,他引:1
H. Katayama-Yoshida K. Sato H. Kizaki H. Funashima I. Hamada T. Fukushima V.A. Dinh M. Toyoda 《Applied Physics A: Materials Science & Processing》2007,89(1):19-27
Based upon ab initio electronic structure calculations for delafossite CuAlO2 and ZnO, we report on the design of new-functional materials for transparent conducting oxides (TCO), such as (i) low-resistive
p-type ZnO and CuAlO2 by co-doping, (ii) high-efficiency thermoelectric power in CuAlO2 (ZT>3) by p-type doping, (iii) half-metallic ferromagnetism in transition-metal-impurity doped CuAlO2 and ZnO-based diluted magnetic semiconductors, and (iv) CaO, MgO, SrO and BaO based DMS without transition metal impurities.
We also discuss the implementation of the self-interaction correction to our materials design method.
PACS 61.72.Bb; 61.72.Jj; 71.15.Mb; 72.15.Jf; 82.75.-d 相似文献