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991.
以中国环境管理干部学院环境法学专业模式构建为研究对象,从专业设置的理论与现实依据、模式建构、专业建设的系列措施、努力方向等方面对环境法学专业建设问题进行了层层剖析,旨在高职高专院校层面、社会层面、教师层面以及学生层面释明设立法学专业的必要性。  相似文献   
992.
公路滑坡灾害链式反应阶段性识别方法研究   总被引:5,自引:2,他引:3  
马保成  王亮  牟顺 《灾害学》2011,26(2):54-58
为了对公路滑坡的发育阶段做出准确判别,研究了公路滑坡灾害发育的链式反应机理,将滑坡的发育阶段划分为3个阶段。采用广泛调研和专家咨询的技术手段,从发育阶段的表现特征中选定了滑坡识别的相关因素集和评分,在此基础上采用模糊数学的方法对公路滑坡灾害的发育阶段进行了识别,并在陕南公路滑坡调查中初步应用。  相似文献   
993.
Six stations in the lower reach region of Changjiang River within Baguazhou Island, Nanjing reach were chosen to investigate the toxic metals pollution characteristic in suspended particle material (SPM). SPM concentration, as well as reflectance spectroscopy characteristic, toxic metal concentrations, and lead isotopes of suspended particle material were studied. SPM concentrations were obtained from fluvial cross-sectional sampling near the surface (20 cm) and the study presents the cross-sectional averages. SPM concentrations varied around 170?C300 mg L???1. Reflectance spectroscopy measurements differed from each other over each cross-section but no common pattern characterizing the cross-sectional behavior of the measurements was observed. The metal concentrations in the SPM decreased in the sequence: Mn > Zn > Cu > Cr > Pb > Cd. The result of lead isotopes analysis proved that lead isotopes composition in SPM are mainly produced by natural contributions and influenced by anthropogenic activity at the same time.  相似文献   
994.
Foshan is the most air-polluted city in Pearl River Delta. Non-methane hydrocarbons (NMHCs) were investigated for the first time in Foshan in winter 2008. Ethene, ethane, ethyne, propane, i-pentane, and toluene were the most abundant hydrocarbons and observed to be higher in Foshan than those in many other cities in China. Different from other cities, ethene and ethane were observed to be the two highest compounds in Foshan. Generally, the most abundant hydrocarbons showed high mixing ratios in the morning (0930-1030 hours), decreased to the lowest level in the afternoon (1430-1530 hours), and increased to higher value in the evening (1930-2030 hours). But i-pentane exhibited a different diurnal pattern with the highest level (13.4 ± 5.8 ppbv) in the afternoon, implying the acceleration of solvent evaporation resulting from higher temperature. Correlation coefficients (R(2)?= 66% for n = 6 at 95% confidence level) of the individual hydrocarbons with ethyne and i-pentane indicated vehicular emissions were the main sources of ethene, propene, i-butene, isoprene, benzene and toluene, while gasoline evaporation was responsible for n-pentane, n-hexane, and n-heptane. The good correlation of most of the hydrocarbons with ethyne, indicating vehicular emissions, were the main sources of NMHCs. B/T ratio was 0.36 ± 0.06, implying vehicular emissions acted as the major contributors as well as additional emissions of toluene emitted from solvent usage. According to investigation, it also suggested that LPG leakage was the main source of propane, while NG leakage was responsible for ethane in Foshan City.  相似文献   
995.
We analyzed occupational exposure to potentially infectious body fluids among health care workers (HCWs). Nurses were the most common exposed category of HCWs. In 73.6% cases needle sticks had been the reason of exposure. Recapping a needle was the cause of exposure in 6.9% accidents. Among 189 registered HCWs, 66 (34.9%) performed invasive procedures without any personal protective equipment. Prophylaxis with antiretroviral drugs was necessary in 43 (22.8%) cases.

As many as 60.3% of exposure incidents to potentially infectious material result from non-compliance with the relevant recommendations. Continuous education and training is critically needed to prevent occupational exposure to blood-borne infections among health care workers.  相似文献   
996.
本文针对社会公众普遍关心的PM2.5及其呼吸防护等问题,从PM2.5的尺寸、组成和危害及自吸过滤式防颗粒物呼吸器的技术要求重点探讨了PM2.5可不可以防、如何来防,以期解除公众对PM2.5的神秘感,同时也提出了公众在面临PM2.5和大气污染时的应对策略。  相似文献   
997.
The iron and steel industry plays a fundamental role in a country's national economy, especially in developing countries. China is the largest iron ore consumption market in the world. However, because of limited domestic iron ore resources, a large proportion of iron ore is imported from other countries. Faced with the conflict between the iron ore supply shortage and the growing demand, it is necessary for the government to predict imports and total consumption. This paper develops a high-precision hybrid model based on grey prediction and rolling mechanism optimized by particle swarm optimization algorithm. We use the China Statistical Yearbook (1996–2011) as our database to test the efficiency and accuracy of the proposed method. According to the experimental results, the proposed new method clearly can improve the prediction accuracy of the original grey model. Future projections have also been done for iron ore imports and total consumption in China in the next five years.  相似文献   
998.
为快速检测海洋石油平台生活污水的COD,同时减少海水中Cl-对数据的影响,崖城海上平台实验室结合自身特点,采用哈希试剂加入一定量硫酸汞的方法来屏蔽Cl-,测量结果达到了预期目标,满足海洋石油海上生活污水快速准确的检测要求。  相似文献   
999.
以近年来我国发生的有影响力的100个环境事件为研究对象,通过多元Logistics回归方法。利用环境污染生境、污染主体特征、污染物特征、对象敏感性、社会敏感性、治理难度和治理效果7类变量23类观测指标解析了影响环境事件发生的显著因素。以此为基础,分别给出了控制和预防大概率小损失、大概率大损失、小概率小损失和小概率大损失环境事件发生的政策建议。  相似文献   
1000.
热解镀层石墨管在无标准分析法测定环境样品中镉的应用   总被引:1,自引:0,他引:1  
马怡载  朱雷 《环境化学》1994,13(4):332-339
本文选择了最佳实验条件和混俣基体改进剂(钯+酒石酸),使热解镀层石墨等有可能用于无标准分析法测定各种环境标准参考物质中的镉。引入有效原子化温度(Teff)概念后,在Teff大于1600K和使用钯和酒石酸为混合基体改进剂,用各种环境标准参考物溶液得到的实验特征量值,接近理论特征量值。  相似文献   
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