Temperature and frequency characteristics of composites with semiconductor fillers

The paper describes the results of a study on the temperature and frequency dependences of the dielectric permeability and dielectric loss tangent of composite materials composed of low density polyethylene filled with cadmium sulfide (LDPE/CdS) and indium(III) selenide (LDPE/In₂Se₃) in the temperature range of 300–450 K and a frequency range of 0–10¹⁴ Hz. It is revealed that a variation in the filler content and the effect of external factors can yield novel composite materials with desired dielectric characteristics.     

Heats of combustion of oil shale, bitumen, and their mixtures

The net calorific values of oil shale, tar oil, bitumen, and their mixtures were measured in a calorimetric bomb. It was found that mixtures of oil shale with tar oil (or bitumen) and coke exhibited the greatest net calorific values. A decrease in the ash content of these mixtures was found. The use of mixture components and ash residues as fuel and building material components, respectively, was proposed.     

The Identification of Data Distribution in Oil Production

Abstract

This article suggests nonparametric criteria for diagnosing changes in process condition based on analysis of data variation.

The developed criteria allow diagnosing changes in conditions of the studied process in cases of data distribution skewness, as well as cases when application of other criteria is not correct or complicated.

The suggested statistical criteria allow simplification of process diagnosis, which are described by multifractal, chaotic fluctuations, and their calculation algorithm can be easily realized.

The applicability of the diagnostic criteria has been proven both in modeled and practical examples of oil production.     

Experimental Investigation of the Density of Caproates at High Temperatures and Pressures

Results of experiments on investigating the density of caproates as a function of temperature and pressure are given. The equation of state of caproates in the liquid phase is composed on the basis of the P––TT data obtained.     

Production of thin-walled castings by the lost-wax process

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 7, pp. 37–38, July, 1989.