摘要:In the present paper ,we discussed a finite element method for a class of2md order quasilinear hyper - bolic--parabolic couuled equations and proved that the FEsolutions and its high order time derivatives possesses the first order uniform superconver-gence and average superconvergence.
摘要:Bisquaternary amonium copounds (BsiQuats) as a new gerneration of ionic surfactants had been made a great progress in the past two decads. More than one hundred compounds have been prepared. The physical chemical properties and the antibacterial properties were studied. This paper is a review of these compounds with 23 references.
关键词:Bisquaternary compounds;surface active agent;Quarternary ammonium.
摘要:Cobalt-phosphine complex catalysts supported in silica were acided, the cobolt ions react with 4 - [(5-chloro - 2 - pyridyl) azo] - 1,3 - diaminobenzene in PH=4-7 medium to form colour coordinate compound and the colour get intensive in acidic medium. Cobalt content was measured with spectrophotometry.
摘要:In this paper, the measuring method of Huggins constant and intrinsic viscosity of polyester at 30℃ is introduced. The results have been compared with the intrinsic viscosity at 25℃ and the error is less than 0. 009
摘要:Uniform design is a new method that is used in experimental study of various factors and various levels. This method can be used in the synthesis of 1 - (4-pyridyl) pyridinium dichloride to design experimental scheme. The yield of the product will be more than 80%.
关键词:Uniform design;Analysis of regression;Dipyridinium.
摘要:The electrochemical and photoelectrochemical properties of a - Fe2O3 thin films are compared with that of a-Fe2o3 thin films. The experiments show that a - Fe2O3 thin film electrodes have a greater anode current, more stable photovoltage and greater pho-tocurrent in 1MKOH resolution. Both of a - Fe2O3 and a - Fe2O3 are n - type semiconductors. The energy level of edge of conduction bands of a - Fe2O3 is higher than that of a -Fe2O3. when illuminated with light, a -Fe2O3 creates more electron - hole pairs, but elec-tronhole paris will be recombinated faster than a-Fe2O3.
关键词:CVD;thin film electrode;Ferric oxide;photocurrent
摘要:determination of poisonous lead in shampoo is very important work. The content of trace lead in shampoo can be measured by single sweep oscillographic polarography. Although there are a lot of measured method, this method is simply, effective analysis method.
关键词:shampoo;content of lead;single sweep;oscillographic polarograpphy
摘要:A mathenatical nodel of heat transformation in 1-dimension is built-up after analyzing the heat transformation in continuous casting tube, and simulated calculation has been conduced by using microcomputer, The results obtained show it saves the time in simulation solidification and the accuracy is precise. This model improves the continuous casting tube technology.
摘要:Lissajous figures are important to determine the frequece. This paper concludes Three experimental methods of obtaining Lissajous figures and their characteristics, and simply introduces the uses of Lissajuus figures