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71.
重庆大气可吸入颗粒物中多环芳烃的分析测定   总被引:4,自引:0,他引:4  
本文报告了重庆大气可吸入颗粒物(IP)中多环芳烃(PAH)的分析测定方法和结果.用GC-MS定性和定量分析了重庆IP中的PAH;研究了IP中PAH的种类和分布情况;确认重庆IP中存在甲基多环芳烃(MePAH)、约占33%;颗粒大小分布表明,约有98%PAH存在于小于3μm的颗粒中.  相似文献   
72.
A complete set of procedure for determination of multiresidue of pesticides in vegetables was presented in this paper.The complete set of procedure included three steps:bioassay,cholinesterase inhibition and GLC analysis.The samples could be identified to be contaminated with pesticides if 5% of house flies was knocked down in 50 tested house flies. Those samples contaminated with pesticides needed to be detected by AChE inhibition method.The qualitative and quantitative analyses were carried out by GLC.Recoveries ranged from 83.7% in Chinese cabbages to 105.6% in tomatoes for pyrethroids,and 84.0% in tomatoes to 102.7% in sweetbell redpeppes for organophosphorus compounds.Coefficients of variations ranged from 0.59% to organophosphorus compounds.Coefficients of variations ranged from 0.59% to 7.87% for pyrethroids. and 0.33% to 9.88% for organophosphorus compounds with vegetables. The complete set of procedure has been used successfully to analyze 7000 samples collected in Beijing. About 1% of the samp  相似文献   
73.
1IntroductionVilageandtownshipindustry(VTI)isbecomingaveryimportantcomponentofChinaseconomyandenvironment.In1992,VTIproduced...  相似文献   
74.
75.
采用温压技术制备铁基粉末冶金材料,研究了干混和湿混两种聚合物添加剂加入方式及压制温度对生坯和烧结体性能的影响,并对其作用机理进行了探讨.试验结果表明,干混混合粉生坯及烧结体的性能略高于湿混混合粉生坯及烧结体的性能,但前者的最佳压制温度范围略高.  相似文献   
76.
应用MARC/autoforge有限元软件对方轧件在椭圆孔型中的轧制温度场进行了热力耦合模拟.研究了模拟过程中的传热边界条件,分析了轧制前和轧制过程中轧件中温度场的分布和变化规律.模拟计算结果和实验结果的比较说明二者基本是相符的.  相似文献   
77.
A total of 198 agricultural soil samples were collected from Zhangjiagang and Changshu in Southern Jiangsu for analysis of 13 polychlorinated biphenyls (PCBs) in order to assess the levels of pollution, sources, area distribution, and potential risk for the environment. All methods were rigorously tested and an adequate quality control was ensured. Only one site had no PCBs residues, and the highest total PCBs concentration in the surface soils was 32.83 ng/g. The average concentration in all the soil samples was 4.13 ng/g, signaling low-level pollution. Tetra-, penta-, and hexa-chlorinated biphenyls were dominant species in soil samples, accounting for more than 75% ofΣPCBs in the soil samples. PCB118 was the most abundant congener in all the samples. The PCB118 was about 20% ofΣPCBs. The soil organic matter content showed only a weak correlation with the levels of all PCB congeners, in which a better correlation was noted for the more volatile lighter PCB congeners than for the heavier homologues. To a certain extent, the sources and land use seemed to influence the levels of PCBs.  相似文献   
78.
Many administrative jurisdictions have authority over parts of the Great Lakes, sometimes with competing purposes as well as governance at differing scales of time and space. As demand increases for high quality information that is relevant to environmental managers, environmental and natural resource agencies with limited budgets must look to interdisciplinary, collaborative approaches for the collection, analysis and reporting of data. The State of the Lakes Ecosystem Conferences (SOLEC) were begun in 1994 in response to reporting requirements of the Great Lakes Water Quality Agreement between Canada and the U.S. The biennial conferences provide independent, science-based reporting on the state of health of the Great Lakes ecosystem components. A suite of indicators necessary and sufficient to assess Great Lakes ecosystem status was introduced in 1998, and assessments based on a subset of the indicators were presented in 2000. Because SOLEC is a multi-agency, multi-jurisdictional reporting venue, the SOLEC indicators require acceptance by a broad spectrum of stakeholders in the Great Lakes basin. The SOLEC indicators list is expected to provide the basis for government agencies and other organizations to collaborate more effectively and to allocate resources to data collection, evaluation and reporting on the state of the Great Lakes basin ecosystem.  相似文献   
79.
对呼吸计量法应用于校准ASM1作了简明的阐述。在呼吸速率与模型组分关系的基础上,介绍了ASM1中废水与污泥各组分浓度的测定方法,并指出模型组分细化的意义。  相似文献   
80.
重点论述了从征、管、用三大环节对环保专项资金进行效益审计。论述了审计方法,提出了存在的问题和建议。  相似文献   
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