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81.
The uniqueness and the global Markov property for the regular Gibbs measure corresponding to the interaction $$U_\Lambda (\varphi ): = \lambda \int\limits_\Lambda {d_2 x\int {d\varrho (\alpha ):e^{\alpha \varphi } :_0 (x)} } $$ [forλ>0,d?(α) a probability measure with support in \(( - 2\sqrt {\pi ,} 2\sqrt \pi )\) ] is proved.  相似文献   
82.
Electron scattering by parallel arrays of charged dislocations in InSb-type semiconductors is considered. In the theoretical approach the nonparabolic structure of the conduction band of the semiconductors considered is taken into account in the approximation of a simplified Kane's band model. The effect of screening by free electrons of the dislocation charge is also included in the theory. The calculated relaxation time of the electrons is used to derive a formula for the dislocation-limited electron mobility in the semiconductors. Some examples of calculations of the charged dislocation-limited mobility as a function of the electron concentration with the dislocation density as a parameter are given for n-InSb at 77 K and 300 K. The ratio of the magnitudes of the charged dislocation-limited mobility to the ionized impurity-limited mobility in n-type material at low temperatures is also discussed.  相似文献   
83.
This paper presents a system that accurately measures the distance travelled by ultrasound waves through the air. The simple design of the system and its obtained accuracy provide a tool for non-contact distance measurements required in the laser’s optical system that investigates the surface of the eyeball.  相似文献   
84.
We study four-dimensional pure gauge field theories by the renormalization group approach. The analysis is restricted to small field approximation. In this region we construct a sequence of localized effective actions by cluster expansions in one step renormalization transformations. We construct also -functions and we define a coupling constant renormalization by a recursive system of renormalization group equations.  相似文献   
85.
The Monte-Carlo model of a light-emitting diode   总被引:1,自引:0,他引:1  
The first complete Monte-Carlo model of a surface light-emitting diode is presented in this paper. In the model all important phenomena (including the two-dimensional diffusion of minority carriers before their recombination in the active region and the re-emission of radiation) are taken into account. The influence of various construction parameters on the external quantum efficiency of the homojunction GaAs diode is examined.  相似文献   
86.
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88.
The resistivity, thermoelectric power and Hall constant in the temperature range of 78–830 K were determined for polycrystalline Th3As4 samples obtained by annealing thin thorium slabs in arsenic vapour. The samples examined were n-type semiconductors with a carrier concentration ranging from 1.0 × 1018cm?3 to 2.8 × 1018 cm?3 for which the effective mass was found to be equal to 0.55–0.76m0. The Hall mobility, about 450cm2V?1s?1 at room temperature, obeys a T?32 law at high temperatures. On the basis of the electrical measurements the forbidden gap of Th3As4 was found to be equal to 0.43 eV.  相似文献   
89.
The first three virial coefficients of a new type in the density expansion of the adsorption isotherm for hard spheres in contact with a wall with a soft surface layer are calculated. The results are compared with those for hard spheres in contact with a hard wall.  相似文献   
90.
A generalization of theG-theory defined by A. Heilet al. is presented.  相似文献   
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