Use of liquid sealants to protect still-waste-containing tanks-settling basins from corrosion

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 10, pp. 29–31, October, 1992.     

A deterministic particle method for the kinetic model of semiconductors: The homogeneous field model

We present a new particle method for the simulation of the semiconductor Boltzmann equation—the weighted particle method. This method differs from the Monte-Carlo method by the approximation of the collision operator—we allocate each particle a weight which varies in time according to the collision integral. This integral is evaluated by means of a quadrature formula, which does not require the use of random numbers. The aim of this paper is to show that this method gives accurate results on physically relevant problems. Linear as well as non-linear collision integrals can be handled the same way by this method. Precise representations of the distribution functions are available, which allow a good insight into the physical processes. In this paper, we only consider the homogeneous field model with an emphasis on the collision operator. Numerical results are presented with a comparison with the Monte-Carlo method.     

The consequences of sampling variability on the estimation of wavenumber and propagation direction from spaceborne SAR image spectra

Even if it were true that SAR (synthetic aperture radar) ocean surface imagery provides a perfect noiseless representation of ocean surface wave height, each spectrum computed from such imagery would be but a single realization of the ensemble-mean ocean spectrum. There would be sampling variability associated with the parameters of dominant wave number and propagation direction extracted from such a spectrum. The present study addresses two questions: (i) what statistical distribution is applicable to the spectra of SAR ocean images? and (ii) what are the consequences of such statistics on the precision with which wave number and propagation direction can be extracted? An examination is made of spectra computed from ocean imagery acquired during the SIR-B (Shuttle Imaging Radar-B) mission     

Ti-silicalite as catalyst for gas-phase ammoximation of cyclohexanone with molecular oxygen

The catalyst behaviour of titanium silicalite, which was found the most active and selective catalyst for liquid-phase ammoximation of cyclohexanone to the corresponding oxime with hydrogen peroxide, was investigated in the gas-phase ammoximation with molecular oxygen in and compared with those of pure silicalite and samples of vanadium and chromium silicalites. The results showed that Ti-silicalite is a selective catalyst not only in the reaction with hydrogen peroxide but also in the reaction with molecular oxygen. However, a big limitation was found in the poor activity of the silicalites which do not allow to reach high oxime yields.     

TCAD and SPICE modeling help solve ESD protection issues in analog CMOS technology

The number of circuit design iterations due to electrostatic discharge (ESD) failures increases with the complexity of VLSI technologies and their shrinking. In this paper, we show how TCAD and ESD SPICE modeling can be used to solve ESD protection issues in an analog CMOS technology.     

Evaluation of the stressed-state of a bed based on emission memory effects of rocks in near-well space

Mining Institute, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 26–29, March–April, 1991.     

On the capacity of a cellular CDMA system

It is shown that, particularly for terrestrial cellular telephony, the interference-suppression feature of CDMA (code division multiple access) can result in a many-fold increase in capacity over analog and even over competing digital techniques. A single-cell system, such as a hubbed satellite network, is addressed, and the basic expression for capacity is developed. The corresponding expressions for a multiple-cell system are derived. and the distribution on the number of users supportable per cell is determined. It is concluded that properly augmented and power-controlled multiple-cell CDMA promises a quantum increase in current cellular capacity     

Vitamin E constituents of Weaning Foods from Germinated Cereals and Legumes

Four weaning food formulations prepared from 70% 72-hr germinated rice/corn and 30% 48-hr germinated mungbean/cowpea were studied for tocopherol constituents and compared to ungerminated controls. γ-TocopheroIs were the major constituents of the mungbean-supplemented samples. The cowpea-supplemented foods contained a predominance of δ-tocopherols followed closely by γ-tocopherols, α-Tocopherols were comparatively higher in corn- than in rice-formulations. Tocopherols in the weaning foods decreased due to germination especially the γ-tocopherols of germinated corn-mungbean.