高效快速多种燃气组分色谱分析法

采用热导检测器，通过几种柱的组合．采用多维柱切换系统，并自动完成阀的驱动和信号切换，实现性质不同的人工煤气和液化石油气主要成分一次进样全自动分析，该方法操作简便、分离效果好、灵敏度高、结果准确可靠．     

双周期Riemann边值问题解法的一个注记

解析函数的边值问题是复变函数的重要分支。许多工程技术、力学物理问题可转化为此类问题或奇异积分方程，而后者的求解又与这类问题有着密切的联系，因此它有广泛的应用价值。本文讨论了当G*∈L时双周期Riemann边值问题的求解方法与可解条件。     

Elementary Investigation of Increasing Polarization Performance of Air Electrode for CO2 Transfer

Air electrodes are the key components of Electrochemical carbon dioxide concentrating(EDC) cells. Therefore, the improvement of the polarization performance is beneficial to the increasing of CO2 transfer and cell stability .The preparing process of air electrode is improved by means of the pretreatment of active carbon(AC) and the selection of preparing method of platinum/carbon(Pt/C) powders. Besides, based on the analysis of orthogonal test results, the optimum preparing conditions of Pt/C powders in air electrode are achieved, that is, hydrazine hydrate concentration is 5%～10%, platinum capacity is 8mg/cm2, chloroplatinic acid concentration is 10.0mg/ml and water both temperature is 40℃.     

关于用基元变换法推导射影公式的问题

给出在射影变换下以原象元素所建立的齐次射影坐标系化为自然坐标系的方法,不妨称作基元变换法.同时给出射影变换的几何意义.     

全球金融危机根源的系统分析

金融危机根源的系统分析从四大层次循序渐进的剖析危机的根源。从个人层次→企业层次→国家层次→全球历史发展的层次来总体系统分析。     

国外鲟鱼类渔业生物学研究现状

概述了国外鲟类生理学、遗传学及生态学领域的研究现状。从微观和宏观两方面描述了国外鲟类成熟性腺、受精卵、胚胎发育、营养生理、遗传分析及生态等内容的研究结果。     

Value of Access to Jobs and Amenities: Evidence from New Residential Properties in Beijing

<正>Introduction When households are faced with the choice of where to live in a city, one of the foremost concerns is the loca-tion’s accessibility to jobs and various other amenities, such as schools, hospitals, and parks[1]. A home in a city is a gateway to urban opportunities, and obviously     

公路路基施工风险分析

目前,路基施工风险管理问题显得尤为突出,文章主要就公路路基施工风险中的公路路基施工质量风险因素进行分析和探讨,以期能提高施工企业风险管理意识,提高企业的风险管理水平,降低企业在施工中的风险水平.     

基于认知的汉英色彩词“黄”的联想意义对比

颜色词“黄”所拓展的联想意义是在人们对色源体认知的基础上再通过联想而获得的。从认知角度分析汉英颜色词“黄”的语义异同之处,剖析影响人们对“黄”语义认知的因素,旨在更好、更全面地了解汉英颜色词“黄”的意义,避免跨文化交际障碍。     

Electrooxidation of Mn(Ⅱ) on Pb-Sb-As Electrode in Sulfuric Acid

The electrooxidation of Mn(Ⅱ) on Pb-Sb-As alloy electrode in sulfuric acid has been investigated.In order to make the two steps of indirect electrosynthesis of benzaldehyde carried out in the same sulfuric acid concentration and also obtain high current efficiency of Mn(Ⅱ) to Mn(Ⅲ) and high yield of Mn(Ⅲ) oxidizing toluene to benzaldehyde in the mean time,the electrooxidation of Mn(Ⅱ) in 60% H2SO4 has been studied.Experimental results show that high current efficiency of Mn(Ⅲ) (about 75%) is obtained in 60%H2SO4 at 60℃.The reason affecting the current efficiency of Mn(Ⅲ) is discussed,and it is the coordination of sulfuric acid concentration and electrolytic temperature.The law is found that it is suitable for electrolysis at low temperature when sulfuric acid concentration is low and at high temperature when sulfuric acid concentration is high.