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991.
The anomalous proximity effect between a d-wave superconductor and a thin disordered normal layer is studied theoretically in the framework of Eilenberger equations. It is shown that disorder of the quasiparticle reflection from this thin layer leads to the formation of an s-wave component localized near the boundary. The angular and spatial structure of the pair potential near the interface is studied. Pis’ma Zh. éksp. Teor. Fiz. 67, No. 7, 478–483 (10 April 1998) Published in English in the original Russian journal. Edited by Steve Torstveit.  相似文献   
992.
In this paper we show that the Boltzmann weights of the three-dimensional Baxter-Bazhanov model give representations of the braid group if some suitable spectral limits are taken. In the trigonometric case we classify all possible spectral limits which produce braid group representations. Furthermore, we prove that for some of them we get cyclotomic invariants of links and for others we obtain tangle invariants generalizing the cyclotomic ones.  相似文献   
993.
994.
A study of the gas-phase parameters involved in ArF laser induced chemical vapour deposition of silicon-oxide thin films is presented. A complete set of experiments has been performed showing the influence of the concentration of the precursor gases, N2O and SiH4, and their influence on total and partial pressures on film growth and properties. In this paper we demonstrate the ability of this LCVD method to deposit silicon oxide films of different compositions and densities by appropriate control of gas composition and total pressure. Moreover, a material specific calibration plot comprising data obtained using different preparation techniques is presented, allowing determination of the stoichiometry of SiO x films by using FTIR spectroscopy independently of the deposition method. For the range of processing conditions examined, the experimental results suggest that chemical processes governing deposition take place mainly in the gas phase.  相似文献   
995.
3-Hydrazino-6-tert-butyl-1,2,4-triazolo[3,4,c]-1,2,4-triazin-5-one was synthesized by the reaction of a substituted 4-(N,N-dimethylcarbamoyl)-3-thioxo-1,2,4-triazine with hydrazine. The spectral characteristics and the proposed reaction mechanism are discussed.The Sumy State University, Sumy 244007. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1258–1260, September, 1994. Original article submitted September 14, 1994.  相似文献   
996.
997.
998.
999.
We solve the problem of the normal and transverse shear in an anisotropic monolith during the excavation of a stratum of solid mineral. It is shown that the stress perturbation field in the rock is due to the whole extent of the excavated portion of the stratum. We study way in which the friction that arises between the interacting rock of the roof and the floor influences the strain and stress fields as the front of the excavation evolves, and also the influence of the extent of the excavated portion of the rock stratum on the magnitude of the accumulated tangential displacements. Three figures. Translated fromTeoreticheskaya i Prikladnaya Mekhanika, No. 25, 1995, pp. 62–69.  相似文献   
1000.
We report new results on the diffraction properties of photoinduced gratings in InGaAs/InGaAsP MQW structures. The original feature of this device is that the QWs are enclosed in an asymmetric Fabry–Perot microcavity in order to increase the diffraction efficiency. We observe oscillations in the diffraction efficiency due to resonant effects in the microcavity. The experimental spectra are compared with theory. Diffraction efficiency at 1.55 μm attains a maximum value of 2.7% at a write beam fluence of 260 μ J cm−2, and then decreases at higher fluences. We explain this phenomenon by an absorption saturation at high excitation.  相似文献   
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