A study of the formation modes of nanosized oxide structures of gallium arsenide by local anodic oxidation

Results obtained in a study of the influence exerted by the technological modes of local anodic oxidation (LAO) on the process in which nanosized oxide structures (NOSs) are formed on the surface of gallium arsenide are reported. The effect of the amplitude and duration of voltage pulses applied to the probesubstrate system, relative air humidity in the technological chamber, and amplitude of cantilever oscillations on the geometric parameters of gallium arsenide NOSs has been examined. It was found that raising the relative humidity from 60 to 90% results in a decrease in the threshold LAO voltage from 7.0 to 6.0 V. It is shown that raising the oscillation amplitude from 0.1 to 2.8 nm leads to a decrease in the NOS height from 3.20 ?? 0.34 to 1.10 ?? 0.13 nm and in the NOS diameter from 218.4 ?? 29.5 to 78.1 ?? 10.3 nm.     

Evolution of aerosols in large pressurized spaces

Results of experiments in pressurized spaces of 100 to 3200 m³, including a manned space station, carried out to study the evolution of aerosols and ions in the course of their spontaneous decay and removal by an electric field or mechanical means are considered. Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 73, No. 4, pp. 844–850, July–August, 2000.     

Numerical simulation of turbulent convection of air in a square cavity heated on the side

A set of three-dimensional unsteady-state equations is used, with the Rayleigh number of 1.58×10⁹, to calculate the turbulent, statistically two-dimensional convection of air in a closed cavity with side walls heated to different temperatures. The turbulence is simulated using the equation of transfer of kinetic energy of turbulent motion, with the dissipation rate calculated differently in the vicinity of and away from the walls. The calculation results are compared with available data of experimental and numerical investigations of other authors. The possibilities are discussed of using this approach to predict averaged characteristics of free convection.