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21.
V. A. Nebol'sin B. M. Darinskii E. E. Popova A. A. Shchetinin 《Russian Physics Journal》1995,38(10):1023-1026
An estimate of the factors which influence the rate of growth of filamentary silicon crystals in a standard chloride system using a quartz reactor with hot walls is given. It is shown that a diffusion form of crystallization is observed under the conditions investigated.Voronezh State Technical University. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 10, pp. 22–26, October, 1995. 相似文献
22.
To investigate local ordering and segregation phenomenon in a Ni91Pt9-alloy after sputtering and annealing a 3D optical atom probe (OAP) has been used. The specimen tips have been prepared from polycrystalline samples. To sputter the samples a separate preparation chamber with a scannable Ar-sputter-gun is connected to the OAP vessel. When necessary, the sample can be electrically heated to induce segregation and cure the altered layer. After a heat treatment of a Ni91 at. %Pt 9 at.% specimen at 1100 K the surface of a (111)-oriented specimen is enriched in platinum by a factor of two in relation to the bulk. The phenomenon of short-range ordering has been investigated on the surface and in the subsurface volume. A 3D reconstruction of this annealed NiPt specimen shows regions with high concentration of platinum that gives an indication at short-range ordering. Uniform sputtering of the tip without a heat treatment induces a decisive depletion of Pt on the surface and the following subatomic layers. The atom-probe results of specimens in thermal equilibrium are in close agreement to further surface sensitive results obtained from Ion Scattering Spectroscopy (ISS) and Auger Electron Spectroscopy (AES). 相似文献
23.
We develop an approach to the solution of the spinless Bethe-Salpeter equation for the different-mass case. Although the calculations are developed for spinzero particles in any arbitratry spherically symmetric potential, the non-Coulombic effective power-law potential is used as a kernel to produce the spin-averaged bound states of the non-self-conjugate mesons. The analytical formulas are also applicable to the self-conjugate mesons in the equal-mass case. The flavor-independent case is investigated in this work. The calculations are carried out to the third-order correction of the energy series. Results are consistent with those obtained before. 相似文献
24.
D. V. Vyalykh A. M. Shikin G. V. Prudnikova A. Yu. Grigor’ev A. G. Starodubov V. K. Adamchuk 《Physics of the Solid State》2002,44(1):164-170
This paper reports on the first experimental observation of quantum-well states and sp-type resonances in thin single-crystal gold, silver, and copper layers formed on single-crystal W(110) surfaces, which result from spatial localization of Bloch-type electronic wave functions in a quantum well with potential barriers at the vacuum/metal and metal/W(110) interfaces. The quantization of the valence-band electronic structure in Au/W(110), Ag/W(110), and Cu/W(110) systems was studied experimentally using angle-resolved photoelectron spectroscopy. 相似文献
25.
The problem of the vector and axial-vector dominance of weak interactions within the framework of the quark model of superconductivity type is discussed. 相似文献
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29.
M. Mirvaliev 《Journal of Mathematical Sciences》1987,38(6):2357-2363
One obtains a formula for the transformation of a vector with a given covariance matrix. The sum of the squares of the components of the transformed vector is equal to a chi-square type quadratic form, constructed with the aid of the initial vector. Taking into account this property, one finds the components of the Pearson statistic, Pearson-Fisher statistic, etc.Translated from Veroyatnostnye Raspredeleniya i Matematicheskaya Statistika, pp. 337–350, 1986. 相似文献
30.
Transport as a consequence of state-dependent diffusion 总被引:1,自引:0,他引:1
M. Büttiker 《Zeitschrift für Physik B Condensed Matter》1987,68(2-3):161-167
Overdamped particles subject to a drift in a force field with sinusoidal space dependence and also a sinusoidally modulated space-dependent diffusion, with the same period as the drift, experience a net driving force. The resulting current depends on the amplitude of the modulation of the diffusion and is a periodic function of the phase difference between the sinusoidal drift and the sinusoidal modulation of the diffusion. For small modulation amplitudes a particle subject to state-dependent noise behaves the same way as a particle subject to thermal noise but with a drift which, in addition to the sinusoidal term, contains a net force term.Dedicated to Professor Harry Thomas on the occasion of his 60th birthday 相似文献