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101.
The purpose of the present work was to investigate the chemistry of rain in the Gulf of Iskenderun, North East Mediterranean, Turkey. The Gulf region has a large number of industries. Main industries existing in the region are iron and steel works, fertilizer plants, a cement plant, and several medium and mini size steel mills in addition to the international pipe line terminals. This study aims to apportion the local sources contributing to the overall pollution of the region. To this end a precipitation sampling program was started in January 2000, and over 48 precipitation samples were collected from each of 5 stations located at Iskenderun city center, Iskenderun industrial zone, Payas city center, the campus of Iskenderun Technical College and the campus of Mustafa Kemal University. Samples were analysed for pH, NO3 +, Cl-. Ca, Al, Ba, Na, Cd, Co, Cr, Cu, Pb, Li, Mg, Mn, Ni, Zn, Fe, K. Concentrations of metal ions were determined by ICP-AES. NO3 - ions and pH were determined by using NO3 - selective electrode and pH meter, respectively.pH values of the collected samples at the industrial zone and at Payas city center, ranged between 5.02 and 7.38, respectively. NO3 - and metal ions concentrations were highly variable. Concentrations of Ca and Fe ions were higher in the industrial zone and Payas city center. In the other three stations, concentrations of metal ions and NO3 - ion were lower than that of industrial zone and the values of pH ranged between 6 and 7.4. The average pH values at Iskenderun Gulf showed that the precipitation was not acidic, because of the high concentration of Ca. The highest concentrations of Na and Cl ions were recorded in the University campus because the campus is located by the Mediterranean Sea.  相似文献   
102.
大庆油田化工总厂废水中化学需氧量(COD)的测定采用库仑法。为了提高质控合格率,从人员素质、仪器设备、电级内液等9个方面分析寻找导致误差的主要影响因素并制定对策。同时对影响电极内液及消解的因素进行正交实验确定最佳条件。结果使库仑法质控合格率由90%提高到95%,测定38次标样全部合格。  相似文献   
103.
废水中甲酸萃取回收的研究   总被引:9,自引:1,他引:9  
以ZYM混合溶剂为萃取剂,以含4.5%的甲酸的废水进行萃取试验,结果表明,ZYM具有良好的热稳定性和再生性,对废水中的甲酸有较高的萃取率。采用本萃取技术,不但具有显著的环境效益,而且还可回收甲酸,获得较好的经济效益。  相似文献   
104.
余江 《化工环保》1996,16(1):48-50
回顾了市场营销对企业发展的核心作用;讨论了环保意识的增强对营销活动的影响以及环保法规与经济调控对企业的巨大压力;介绍了适应时代要求的社会环境营销观的内容及对现代化工企业的影响,并对化工企业如何树立新型营销观进行了探讨。  相似文献   
105.
Hazard and operability (HAZOP) studies constitute an essential step in the risk analysis of any chemical process industry and involve systematic identification of every conceivable abnormal process deviation, its causes and abnormal consequences. These authors have recently proposed optHAZOP as an alternative procedure for conducting HAZOP studies in a shorter span of time than taken by conventional HAZOP procedure, with greater accuracy and effectiveness [Khan, F. I. and Abassi, S. A., optHAZOP. An effective and efficient technique for hazard identification and assessment Journal of Loss Prevention in the Process Industries, 1997, 10, 191–204]. optHAZOP consists of several steps, the most crucial one requires use of a knowledge-based software tool which would significantly reduce the requirement of expert man-hours and speed up the work of the study team. TOPHAZOP (Tool for OPTmizing HAZOP) has been developed to fulfil this need.

The TOPHAZOP knowledge-base consists of two main branches: process-specific and general. The TOPHAZOP framework allows these two branches to interact during the analysis to address the process-specific aspects of HAZOP analysis while maintaining the generality of the system. The system is open-ended and modular in structure to make easy implementation and/or expansion of knowledge. The important features of TOPHAZOP and its performance on an industrial case study are described.  相似文献   

106.
杨健  周小波 《四川环境》2006,25(1):1-3,7
高浓度酒精糟液经厌氧生物处理后排出的消化液COD浓度为4500—6000mg/L,SS浓度高这1500—2.600mg,/L,且由于微小沼气泡附着在厌氧污泥上,沉降性能很差,难以与消化液相分离,对后续处理十分不剁。本研兜采用预曝气.化学混凝沉淀组合工艺,对该消化液进行去除高浓度SS的顸处理试验,研究探讨了曝气时间、混凝剂种类和投加量对SS和COD去除效果的影响。试验结果表明,预曝气.化学混凝沉淀组合工艺对消化液SS的去除效果十分显著。当预曝气时间为6.0h,FeCl3投加量为100mg/L时,消化液的SS去除率75.4%,COD去除率24.3%,可为后续的好氧生物处理提供较为有利的水质和负荷条件。  相似文献   
107.
In multiphase systems capillary pressures play a significant role on fluid movement and retention. The facility to predict the effect of different thermal remediation strategies requires the knowledge of the effect of temperature on capillary pressure-saturation relationships in the soils. The objective of recent study was (a) to develop a technique for routinely measuring the pressure-saturation curves of soil samples saturated with a nonpolar liquid at different regulated temperatures (b) to build a database using the measured pressure-saturation curves and the physical, chemical properties of the model soils (c) to establish the dependence of nonaqueous phase liquid retention on the soil properties and the temperature. The retention curves (extraction isotherms) with nonaqueous phase liquid were determined using a modified pressure plate extractor. The wetting phase was a non-aromatic hydrocarbon distillation product. Pressure plates were designed and constructed in the laboratory of our department. The temperature was held constant at 20, 40 and 60 C. Statistical analysis was performed involving selected soil parameters and the measured nonaqueous phase liquid retention data. The results show that knowing some easily measurable soil parameters (bulk density, particle size distribution, humus and lime content) we can estimate the nonaqueous phase liquid retention of the soils. The measured “extraction isotherms” provide essential information about the temperature-dependency of pressure-saturation curves.  相似文献   
108.
火龙果果皮色素的提取及稳定性研究   总被引:11,自引:0,他引:11  
研究了火龙果果皮色素提取的最佳条件、提取液的稳定性和各种添加剂对提取液稳定性的影响。  相似文献   
109.
枇杷核中提取苦杏仁甙的研究   总被引:1,自引:0,他引:1  
研究了3个枇杷品种的出核率,利用高效液相色谱检测苦杏仁甙的含量,以及从枇杷核中提取苦杏仁甙的工艺。结果表明,3个品种烘干后核的得率存在显著差异,干核的年产量很大,有综合开发利用价值;提取溶剂以乙醇为好,最合理的工艺组合为:在原料中按料液比1:10加入浓度为80%的乙醇,在65℃时回流提取50min。在40℃功率为80W的条件下超声处理25min。合理选择品种是提高苦杏仁甙得率的关键。  相似文献   
110.
野生一年蓬的开发利用   总被引:2,自引:0,他引:2  
阐述了野生植物一年蓬的植物学特性、分布习性、化学成分、开发利用价值等,为其进一步开发利用乃至产业化、现代化生产提供参考。  相似文献   
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