加热炉炉管穿孔事故处理及原因分析

以一起直接式原油加热炉炉管穿孔事故为例,介绍了事故处理程序,分析了炉管穿孔的原因是由于漏点腐蚀、坑点腐蚀以及炉管管卡损坏导致的,并提出了类似事故防范对策.     

蒙城地震台地磁绝对观测数据处理分析软件

蒙城地震台地磁绝对观测数据主要通过手工方式计算处理,由于内容多而繁琐,很容易出现人为错误,而且工作效率不高。本文介绍了“蒙城地震台地磁绝对观测数据处理分析软件”,该软件将绝对观测日常数据处理工作有效整合,形成了流程,提高了数据处理效率。并能够对数据进行误差统计、趋势分析等,以了解观测资料的实际状况。     

有机气溶胶组分对六氯苯光解的影响

以高压汞灯为光源,分别研究了六氯苯在正己烷和邻苯二甲酸二异辛酯(DIOP)为有机气溶胶表层模拟介质时的光解,发现六氯苯在正己烷和DIOP中的光解半衰期分别约为<5 min和5 h,相差70倍以上.研究发现蒽醌和甲氧酚类气溶胶组分对六氯苯的光解具有光敏化作用,其反应机制可能分别为能量转移和抽氢反应.六氯苯光解的主要产物是五氯酚.     

Chemical characterization of fine particles from on-road vehicles in the Wutong tunnel in Shenzhen, China

Vehicle populations in China have been increasing sharply since 1990s. Vehicle emissions including various gaseous pollutants and particulate matter cause deterioration of air quality. However, measurements of particulate mater from on-road vehicles in China are scarcely reported, and thus the chemical compositions of particles emitted from vehicles in China are unknown. In this research, tunnel experiments were performed to measure PM2.5 in the Wutong tunnel, Shenzhen, China. Detailed PM2.5 chemical compositions, with organic compounds determined by GC/MS, in the tunnel were presented. Elemental carbon and organic matter composed 63% and 34% of the total PM2.5 mass in the Wutong tunnel, respectively. Alkanes, PAHs, hopanes, fatty acids, and dicarboxylic acids were the major identified organic compounds, and their source profiles in the PM2.5 in the Wutong tunnel were characterized. The comparisons of our measurements with those in the literature were also made to demonstrate the characteristics of the vehicle source profiles in the Wutong tunnel. The experimental results in this paper can improve understanding of particulate matter emitted from vehicles in China.     

Effects of riboflavin on the phototransformation of benzo[a]pyrene

Riboflavin (Vitamin B2) is a natural dye-sensitizer habitually present in natural waters. Effects of riboflavin as photosensitizer on the transformation of benzo[a]pyrene (BaP) (10 microM) in the aqueous-organic solvent (water/acetonitrile/methanol 50/40/10) were investigated in this study. The photolysis half life of BaP in solution containing 50 microM riboflavin was 5 min, compared to 98 min in the absence of riboflavin. The rate of phototransformation of BaP increased as the concentration of riboflavin was raised from 10 microM to 100 microM under both natural sunlight and UVA irradiation. The half life of BaP in the presence of 50 microM riboflavin was 10.6 min and 43.1 min when exposed to visible range of natural sunlight and UVA irradiation respectively. Riboflavin decomposes under natural sunlight. Lumichrome, a principal photoproduct of riboflavin, was shown to photosensitize BaP under natural sunlight after photolysis of riboflavin. Our study indicated that other photoproducts from riboflavin, such as lumiflavin, were also involved in the phototransformation of BaP under sunlight when riboflavin diminished. The major photoproducts in the photolysis of BaP were identified as 1,6-benzo[a]pyrene-dione, 3,6-benzo[a]pyrene-dione, 6,12-benzo[a]pyrene-dione by using high performance liquid chromatography (HPLC). All these products were detected in the samples which were irradiated under different light sources and in the presence or absence of riboflavin. The possible phototransformation mechanism was discussed.     

Analysis of regional and temporal characteristics of PM10 during an Asian dust episode in Korea

This study analyzes the regional and temporal distributions of PM10 concentrations observed in major metropolitan cities in Korea before, during and after a recent Asian dust episode in 2002. There were spatial and temporal variations in PM10 concentrations among the mid-western, the southwestern, the southeastern, and the southern parts of Korea during this Asian dust period due to the different air mass movement time and the different wind directions and speeds of prevailing winds in each city or region. The origins of the three-day Asian dust episode were identified by an analysis of two-day backward isentropic air trajectories. The different origins for each day also significantly contributed to the spatial and temporal variations in PM10 concentrations. A significant relationship was found between PM10 concentrations on the day preceding the first peak day and the first peak day of the Asian dust period but only in the mid-western areas. The concentrations of PM10 just after the Asian dust episode were much higher than those just before. There was a significant increase in a coarse fraction, having soil origins, of particles during the Asian dust episode. Concentrations of Mn, Fe, Ni and Cr extracted from the total suspended particulate (TSP) samples collected in 7 cities during the Asian dust episode were much higher when compared with other days in 2001. However, the Asian dust did not consistently increase the concentrations of lead, cadmium and copper as they are influenced by local sources such as local traffic or industrial emissions.     

Adsorption of branched alkylbenzene sulfonate onto styrene and acrylic ester resins

In this study, a series of acrylic ester resins were prepared and characterized. The adsorption behaviors of sodium 6-dodecyl benzenesulfonate (6-NaDBS) on styrene resin XAD-4 and acrylic ester resins have been studied. As compared to commercial acrylic ester resins Amberlite XAD-7 and Diaion HP2MG, YWB-38, one of the as-prepared resins, exhibits better adsorption properties toward 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir and double-Langmuir models. The two models provide very good fit for all acrylic ester resins over the temperature range studied, whereas fitted results for styrene resin XAD-4 are less accurate. The investigation indicates that the adsorbate molecules are directly adsorbed on acrylic ester resins as a bi-layer, while the molecules are adsorbed on XAD-4 as monolayer formation followed by the establishment of bi-layer. Adsorption kinetics and elution processes were also investigated for further exploring the adsorption behavior and mechanism on styrene resin XAD-4 and YWB-38.     

"三大定律"警示基层安全管理工作

近两年来,频繁发生的"12·23重庆井喷"、"4·15重庆天原化工厂氯气泄漏"、"吉化11·13苯泄露事件"等等安全事故,让人触目惊心.从这些事故原因中,我们不难看到钻井作业卸掉"防喷阀"、危险化学品车辆押运员"逃逸"、化工厂职工现场"处置不当"等不安全状态(侥幸心理和麻痹大意思想)是导致这些事故发生的直接原因.我们安全管理人员在分析以上事故原因,吸取惨痛教训的同时,不能忽视事故发生的规律,并且应注重"安全管理三大定律"对基层安全管理和安全培训教育工作的启示.     

现代城市居住区的防盗安全问题研究

针对现代城市居住区防盗安全问题日益突出的情况,从住宅建筑方面入手,对城市居住区的防盗安全问题进行研究分析,并提出相应的解决措施.其中分别对住宅建筑的窗、住宅平立面、阳台、住宅楼梯间、雨篷、管道和空调主机七个细节部位进行了防盗分析;在安全设计时充分考虑各个细节部位之间的联系,本着"相互促进,相辅相成"的原则,对它们的整体布局、安放位置和尺寸等方面提出了改进方案,并实施了防盗安全设计.     

Al13形态在混凝中的作用机制

从铝的水解形态转化角度考察了铝盐在高碱度和高有机物浓度水体中的混凝行为.结果表明,铝盐的混凝效能是与混凝过程中的Al₁₃含量成正比.高投药量时氯化铝(AlCl₃)既可以有效调节水体pH值又能在混凝过程中原位水解产生较多的Al₁₃形态,因而混凝效能要高于聚合氯化铝(PACl).在铝盐混凝中,调节pH值到6～7之间可以控制铝形态分布从而达到提高混凝效能和减少残留铝的目的.在调节pH值强化混凝的方法中使用传统铝盐的效果要好于无机高分子絮凝剂.