Refractory Materials Resistant to Quartz Glass in Vacuum at 1600-1700°C

Graphite materials with coatings based on boron nitride and molybdenum disilicide were studied in order to find a way to prevent reaction of quartz glass with graphite members.     

New X-Ray Techniques for Flow Visualization and Measurement of Hydrodynamic Flow Parameters in Opaque Heterogeneous Media

This paper proposes and validates a method for the quantitative analysis of multiphase flows and objects of complex composition with image registration on a charge-coupled-device array taking into account the X-ray spectral characteristics. The method was tested on objects of known composition and shape. New approaches are formulated to solve a number of research problems related to the use of modern registration techniques and computer-based tools for X-ray image processing. __________ Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 6, pp. 159–170, November–December, 2005.     

Noise rectifier based on the two-dimensional electron gas

The dc voltage observed at low temperatures in a 2D electron sample in the absence of noticeable external excitations [1] is accounted by the Schottky contact rectification of the noise generated in the measuring circuit. The rectified voltage is shown to depend on the asymmetry of the contact pair. The dependence of the rectified voltage on the noise amplitude first follows the trivial quadratic law, then exhibits a nearly linear behavior, and finally, levels off.     

Electric field effect on crystallization kinetics

The effect of a dc electric field on the kinetics of dielectric crystallization is considered. It is shown that the electric field has a significant effect on the rate of nucleation, the linear rate of crystallization, and the time for complete crystallization of a given volume of mother liquor, and also leads to structural changes in the crystallizing solid phase.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 63–67, February, 1979.     

Verification of the nature of the approximation of the Boltzmann integral by Krook's kinetic relaxation model

Up to now a significant number of aerodynamic problems have been solved with the aid of Krook's kinetic relaxation model. However, because of the absence of reliable solutions of boundary problems for the Boltzmann equation, the correctness of the assumed model of the collision integral remains unclarified. In the present paper, in order to verify the nature of the approximation of the collision operator by the given model, a machine experiment is undertaken. The Boltzmann collision operator is computed for a variety of test functions characteristic of the motion of a rarefied gas and the values obtained according to it are compared to the Krook model. Some physical hypotheses embedded in the relaxation model are also examined.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 3–7, July–August, 1970.     

Quantum Hall effect: The resistivity of a 2D electron gas—a thermodynamic approach

Based on a thermodynamic approach, we have calculated the resistivity of a 2D electron gas, assumed dissipationless in a strong quantum limit. Standard measurements, with extra current leads, define the resistivity caused by a combination of Peltier and Seebeck effects. The current causes heating (cooling) at the first (second) sample contacts, due to the Peltier effect. The contact temperatures are different. The measured voltage is equal to the Peltier effect-induced thermoemf which is linear in current. As a result, the resistivity is non-zero as I→0. The resistivity is a universal function of magnetic field and temperature, expressed in fundamental units h/e². The universal features of magnetotransport data observed in the experiment confirm our predictions.