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351.
盐酸付玫瑰苯胺是三苯甲烷类染料,分子中存在的共轭体系使其具有以下特性:1.本身带色;2.随介质的pH变化产生显著的颜色效应,pH值越高,颜色越深,pH值越低,颜色越浅;3.对光和水洗的坚牢度较差;4.可发生重氮化反应;5.杂质使其颜色加深。  相似文献   
352.
对绵阳市的环境放射源基本情况进行了分析,弄清了放射源的品种、数量。摸索出放射性核素及X射线装置在地域、行业和剂量方面的分布规律,揭示出环境放射性管理工作的重点。  相似文献   
353.
通过对大气细菌数量、霉菌数量与风速相关性的研究,得出齐市地区冬季气候寒冷,无相关性;春季气候干燥,风沙大,有相关性;雨后大气细菌数量与风速无相关性,大气霉菌数量与风速相关。  相似文献   
354.
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   
355.
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   
356.
指出水产品代谢物的排出及没有被水产品利用的残饵是造成渔业养殖中水环境污染的重要原因之一。针对渔业污染物的生成情况,提出了渔业污染物排放总量的3种核定方法:实测法、物料平衡法、经验系数法。  相似文献   
357.
介绍TEOM®RP1400a(PM10)测尘仪原理、工作过程以及日常维护、质量控制和常见故障的排除方法.  相似文献   
358.
杨继明  宋洋  白俸洁 《干旱环境监测》2003,17(4):195-196,221
根据流动相极性理论,采用梯度淋洗一检测器编程方法检测多环芳烃,大大缩短了分析时间,并提高了灵敏度和精密度.为进一步定量分析提供了优良的途径。  相似文献   
359.
灰色模型在确定关键污染因子中的应用   总被引:1,自引:2,他引:1  
将灰色模型引入水环境质量评价中 ,通过对某个时间段内污染物原始监测数据的灰色处理 ,从动态演变中找出关键因子 ,客观地判定各污染因子所起的作用 ,并对各因子在下一个时间段的发展趋势作出判断 ,增加了评价的准确性。经过实例运用分析表明 ,该方法物理意义明确 ,简便易用  相似文献   
360.
A study of the elemental leachability and retention capability of compost   总被引:2,自引:0,他引:2  
In this work a comparison is made between the different approaches that can be taken to evaluate the mobility of elements in compost. The practical consequences of the results obtained are also discussed in terms of methods for cleaning up compost and using compost in environmental remediation. The mobility of potentially toxic elements in compost is evaluated by leaching with four selected eluents, i.e. diluted sulfuric acid, oxalate, citrate and EDTA. In contrast to the chelating agents, diluted sulfuric acid was found to generally have a low leaching capability for removal of heavy metals from compost. This implies that the risk of heavy metal leaching caused by natural rainfall is likely to be low. The results obtained in the leaching experiment were compared with previous results obtained from sequential fractionation. This comparison confirmed that both methods gave similar results for predicting the lability of elements in compost. A non-linear regression analysis of the leaching curves was also conducted. The leaching curves for elements with high lability could be fitted with a two components model. The labile components identified by the kinetic model are approximately in accordance with the fractions obtained from the first step of the sequential extraction method. The kinetic speciation method is shown to be a relatively rapid and simple procedure for compost which gives more information about element lability than simple leaching experiments. The leaching reagents used in this work were not effective enough to be used for cleaning up compost with a high metal content. Compost was however shown to have a high affinity for heavy metals, with the order of affinity of metal for the compost being very similar to that seen for humic acid. Compost may therefore prove to be a good remediation material for metal contaminated waste.  相似文献   
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