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101.
80年代初和80年代末对黄河宁夏段的经济鱼类的含汞水平进行了监测,结果表明:这段河道的汞污染对经济鱼类的影响起来越严重,超标率由32%~38%发展到100%,1988年鲶鱼含汞达2.47mg/kg,超标7.2倍.  相似文献   
102.
为了筛选蚕豆叶尖微核监测技术敏感材料,以二甲苯为污染物,对甘肃产的10个蚕豆品种进行了测试。结果表明,蚕引8号微核出现率与二甲苯诱变剂浓度成正比,平均微核率差异极显著,是监测评价二甲苯污染的敏感品种。  相似文献   
103.
16 priority polycyclic aromatic hydrocarbons (PAHs) were determined in water samples from the Jinsha River (Panzhihua part), Southwest China. Total dissolved PAH concentrations varied from 21.89 microg l(-1) to 382.8 microg l(-1). It was found that the concentration of PAHs decreased along the flow direction due to the higher density distribution of coal chemical industry in the upstream of our study rivers. The pollution levels in our study area are significantly higher than previously reported values in other waters both in China and other countries. The predominance of benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene was clearly observed in all water samples. On average these two compounds accounted for 98.3% of the total dissolved PAH concentration in water. The results showed the positive correlations among total dissolved PAHs, benzo[k]fluoranthene and indeno[1,2,3-cd]pyrene, which suggested that these two predominant PAHs have similar source and environmental behaviors in our study area. When compared with the survey results of organic micropollutants two decades ago, it was found that hydrocarbon pollution both predominated and even increased with the development of coal chemical industry in this area during the past 20 years. The results therefore provide important information on the current contamination status of a key industrial city in China, and points to the need for urgent action to investigate the relationship between the PAH composition and concentration in water from the Jinsha River and the wastewater discharge from coal chemical industry, and to identify the source, transport pathway and fate of PAHs in the area. It should then be necessary to adopt appropriate and instant measures to control the pollution around this area.  相似文献   
104.
A distributed hydrologic modeling and GIS approach is applied for the assessment of land use impact in the Steinsel sub-basin, Alzette, Grand-Duchy of Luxembourg. The assessment focuses on the runoff contributions from different land use classes and the potential impact of land use changes on runoff generation. The results show that the direct runoff from urban areas is dominant for a flood event compared with runoff from other land use areas in this catchment, and tends to increase for small floods and for the dry season floods, whereas the interflow from forested, pasture and agricultural field areas contributes to the recession flow. Significant variations in flood volume, peak discharge, time to the peak, etc., are found from the model simulation based on the three hypothetical land use change scenarios.  相似文献   
105.
Measurements of aerosols were made in 2001 and 2002 at Dunhuang (40 degrees 00'N, 94 degrees 30'E), China to understand the nature of atmospheric particles over the desert areas in the Asian continent. Balloon-borne measurements with an optical particle counter suggested that particle size and concentration had noticeable peaks in super micron size range not only in the boundary mixing layer but also in the free troposphere. Super-micron particle concentration largely decreased in the mid tropopause (from 5 to 10 km; above sea level, a.s.l.). Lidar measurements made during August 2002 at Dunhuang suggested the possibility that mixing of dust particles occurred from near the ground to about 6 km even under calm weather conditions, and a large depolarization ratio of particulate matter was found in the aerosol layer. The top of the aerosol layer was found at heights of nearly 6 km (a.s.l.). It is strongly suggested that nonspherical dust particles (Kosa particles) frequently diffused in the free atmosphere over the Taklamakan desert through small-scale turbulences and are possible sources of dust particles of weak Kosa events that have been identified in the free troposphere not only in spring but also in summer over Japanese archipelago. Electron microscopic experiments of the particles collected in the free troposphere confirmed that coarse and nonspherical particles observed by the mineral particle were major components of coarse mode (diameter larger than 1 microm) below about 5 km over Dunhuang, China.  相似文献   
106.
几种土壤质量评价方法的比较   总被引:20,自引:0,他引:20  
分别用T值分级法,综合指数法,模糊数学综合评判法,灰色聚类法,等斜率灰色聚类法,宽域灰色聚类法对湖南某地10个监测点的土壤质量现状进行评价,通过比较,认为宽域灰色聚类法较好。  相似文献   
107.
在ψ(H2SO4)=56%硫酸介质,重铬酸钾的氧化体系中,以钼权铵,硫酸铝钾为助催化剂,可减少量化剂硫酸银的用量,消解15min即可测定水中化学需氧量,用硝酸银溶液代替硫酸汞去除水氯离子,避免了汞盐的污染,工业废水回收率在97%~101%之间,有较好的准确度。  相似文献   
108.
环境中萘和甲基萘的气相色谱测定   总被引:3,自引:0,他引:3  
针对发生的甲基萘油车泄漏事故进行了水样和空气样品中萘和甲基萘的测定,水样中直接进样,对空气样品则以甲醇为吸收液吸收,富集,氢火焰毛细管色谱法测定。  相似文献   
109.
光离子化检测器便携式气相色谱仪快速测定空气中苯系物   总被引:3,自引:0,他引:3  
本文研究了使用光离子化检测器便携式气相色谱仪,直接测定空气中mg/m3级苯系物(苯、甲苯、乙苯、邻、间、对位的二甲苯及异丙苯)的快速分析方法。方法的线性范围为0~100mg/m3,相关系数均在0.999以上,方法的变异系数分别为2.9~12.5%(5mg/m3),3.4~7.9%(30mg/m3),方法最低检测限达0.2~1.0mg/m3。  相似文献   
110.
连续同时监测天津市大港石化发展规划区区域废水中的CODCr和CODMn,并考查其线性相关性后得出CODCr=4.96CODMn+116.3,相关系数为0.750。该回归方程适用于类似石油化工工业区区域废水中CODCr和CODMn间的换算  相似文献   
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