Analysis of organic compounds in coal gasification wastewater

A procedure for analysis of organic pollutants in coal gasification wastewater was developed, including a series extraction steps at different pH, followed by LC separation or resin adsorption, then analyzed by GC or GC/MS. More than 200 organic pollutants in 22 categories were determined. CH2CL2 extraction at NaHCO3 presence was used to separate carboxylic acids with phenolic compounds in aqueous. Derivatization with acetic anhydride was used for analyses of mono-, di-, poly-hydroxyl phenolic compounds. 21 mono-hydroxyl phenols and 13 di-hydroxyl phenols were determined from the coai gasification wastewater samples. Derivatization with BF3-CH3OH was used for analysis of carboxylic acid. 17 mono-carboxyl, 4 di-carboxyl acids and 6 aromatic acids were determined from coal gasification wastewater samples.     

Kinetics of hydrogen peroxide-sulfur (IV) reaction in atmospheric precipitation

The kinetics of the reaction of dissolved S(IV) with H2O2 was studied on 59 precipitation samples collected in Southwestern China, during the period of June 1988 to October 1989, from which the oxidation rates of the reaction were measured. The extent of reaction was followed by continuous amperometric measurement of the concentrations of the reagents. The two systems (i. e. rainwater and purified water) have been studied with the same methodology under identical reaction conditions (e. g. reagent concentrations, ionic strength and temperature). The kinetics was studied in no buffer solutions. The effect of formaldehyde on the reaction has also been studied, including kinetic studies in laboratory and model calculations, and it is indicated that formaldehyde with typical atmospheric concentration exerts no influence on the reaction of dissolved S(IV) with H2O2. In addition, the activation energy of the reaction was also measured in purified water as reaction medium for temperature range 0-50℃ at pH 4.0     

水平波纹板组处理含油废水

采用水平波纹板组处理含油废水。通过正交小试,筛选出最佳波纹板,并对不同板间距、流速、原水温度以及油种作了除油效率影响试验。在此基础上,进行了水平波纹板除油装置的放大并用于实际含油废水处理的试验。结果表明.该除油技术可用于非乳化的含油废水处理。与目前国内其它重力分离技术相比,具有除油效率高(95％以上)和能去除20μm以下的微小油珠的特点。     

SBR法处理化粪池出水的工艺研究

采用经实验运行得到SBR工艺处理化粪池出水的合理的操作模式,能获得90%以上稳定的COD_(cr)去除率及更好的BOD_5去除效果,NH_3-N去除率大于75%,TN去除率大于45%.并考察了污泥浓度、泥龄、污泥负荷与处理效果的关系,以及闲置期对反应周期的影响.实验结果表明,SBR工艺对处理水质、水量负荷变化很大的化粪池出水,是一种理想的工艺选择.     

钢窗手柄冷楔横轧工艺

分析了楔横轧成形条件,以冷楔横轧钢窗手柄为例探讨了工艺方案选择和工艺参数确定.试轧获得基本成功.如用于实际生产尚须进一步提高加工精度.     

Detoxifying moniliformin in grains and water

ＤｅｔｏｘｉｆｙｉｎｇｍｏｎｉｌｉｆｏｒｍｉｎｉｎｇｒａｉｎｓａｎｄｗａｔｅｒＺｈａｎｇＨｏｎｇ，ＬｉＪｉｌｕｎＣｏｌｅｇｅｏｆＢｉｏｌｏｇｉｃａｌＳｃｉｅｎｃｅｓ，ＣｈｉｎａＡｇｒｉｃｕｌｔｕｒａｌＵｎｉｖｅｒｓｉｔｙ，Ｂｅｉｊｉｎｇ１０００...     

125型摩托车铝合金车轮的液态挤压成型

分析了125型摩托车铝合金车轮的特点,介绍了车轮液态挤压成型模具的设计及液态挤压成型的整个工艺和生产过程中应注意的问题.     

计算机辅助法兰类锻件计算

此文分析了常见几种法兰锻件图特点,给出了法兰锻件图上各圆角圆心坐标及圆弧和相邻线段的切点坐标及法兰锻件体积计算公式,并进—步采用计算机辅助计算锻件体积,提高了计算精度并大大减轻了手工计算的繁重劳动。     

不除氧单扫描示波极谱法测定茶叶中钙

研究了在不除氧条件下，用单扫描示波极谱法测定茶叶中钙，在０．０２ｍｏｌ／Ｌ ＫＯＨ体系中，钙－桑色素络合物于－０．７８Ｖ产生一灵敏的极谱峰，峰电流与钙浓度在０．１￣０．８μｇ／ｍＬ之间有良好的线性关系。方法灵敏、准确、简便、选择性好。