首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   266篇
  免费   14篇
  国内免费   75篇
安全科学   22篇
废物处理   11篇
环保管理   19篇
综合类   140篇
基础理论   46篇
污染及防治   62篇
评价与监测   23篇
社会与环境   16篇
灾害及防治   16篇
  2023年   3篇
  2022年   13篇
  2021年   19篇
  2020年   22篇
  2019年   16篇
  2018年   14篇
  2017年   23篇
  2016年   22篇
  2015年   19篇
  2014年   15篇
  2013年   24篇
  2012年   21篇
  2011年   28篇
  2010年   22篇
  2009年   19篇
  2008年   12篇
  2007年   11篇
  2006年   2篇
  2005年   5篇
  2004年   4篇
  2003年   7篇
  2002年   13篇
  2001年   2篇
  2000年   10篇
  1999年   3篇
  1998年   1篇
  1996年   1篇
  1995年   1篇
  1994年   1篇
  1993年   1篇
  1992年   1篇
排序方式: 共有355条查询结果,搜索用时 500 毫秒
301.
Endocrine disrupting chemicals (EDCs) in the secondary effluent discharged from wastewater treatment plants (WWTPs) are of great concern in the process of water reuse. Ozonation has been reported as a powerful oxidation technology to eliminate micropollutants in water treatment. Due to the complexity of the wastewater matrix, orthogonal experiments and single factor experiments were conducted to study the influence of operational parameters on the degradation of 17αup-ethinylestradiol (EE2) in the synthetic secondary effluent. The results of the orthogonal experiments indicated that the initial ozone and natural organic matter (NOM) concentration significantly affected EE2 degradation efficiency, which was further validated by the single factor confirmation experiments. EE2 was shown to be effectively degraded by ozonation in the conditions of low pH (6), NOM (10 mg/L), carbonate (50 mg/L), but high suspended solid (20 mg/L) and initial ozone concentration (9 mg/L). The study firstly revealed that the lower pH resulted in higher degradation of EE2 in the synthetic secondary effluent, which differed from EDCs ozonation behavior in pure water. EE2 degradation by ozone molecule instead of hydroxyl radical was proposed to play a key role in the degradation of EDCs by ozonation in the secondary effluent. The ratio between O3 and TOC was identified as an appropriate index to assess the degradation of EE2 by ozonation in the synthetic secondary effluent.  相似文献   
302.
高思红 《环境技术》2013,(6):45-46,51
本文综述了若干影响光纤特性的环境因素,如潮气,各种类型的机械力,腐蚀,氢气,雷电,核电磁脉冲及电离辐射,这些因素会使光纤极化面偏转,衰减增加,误码率加大。文中还扼要介绍了为减少这些环境危害影响所采取的若干措施。  相似文献   
303.
Hu Si  Hong Ji  Xiaohong Zeng 《Safety Science》2012,50(7):1452-1461
The hazardous chemical accidents remain a matter of major concern. However, there is a dearth of practical measures about the emergency management of hazardous chemicals leakage. Therefore, in order to provide more accurate management plan, quantitative risk assessment has become a critical issue in chemical industry. The main aim of this study is to quantify the risk of hazardous chemicals leakage, and take precautions against the accidents. In this study, a Fire-Explosion-Poisoning Quantitative Probability Model (FEPQPM) has been established. The paper introduced the probability analysis methods to analyze derivative accidents caused by hazardous chemicals leakage, established quantitative risk assessment models, and made acceptable risk level analysis. This model has been applied to quantitatively assess an enterprise’s storage tank at Changshou Chemical Industrial Distripark (CID) in Chongqing, China. Evaluation results are in line with the actual situation of the CID. It is shown that the probability of poisoning is very large, causing more economic loss than the other two types of accidents, and death toll of leakage accident increases over time, resulting in greater economic losses. The risk level of leakage accident involving poisoning is unacceptable.  相似文献   
304.
Effects of human activity on the distribution of phosphorus (P) forms were investigated for the sediments and porewaters in Daqinghe Estuary of Dianchi Lake, China. The concentrations of total P (TP), inorganic-P (I-P),and organic-P (Org-P), and the ratio of iron-bound P (Fe-P)/calcium-bound P (Ca-P) in the sediments decreased with the increasing distance from the sampling site to the estuary. This is probably due to the flocculant materials, e.g., ferric and aluminous salts, usually being added in the wastewater treatment processes. The concentration of ammonia in the sediment porewaters significantly decreased with the increasing distance from the sampling site to the estuary. Both concentrations of total nitrogen and nitrogen in the sediment porewaters decreased to some content with the increasing distance from the sampling site to the estuary. However, the concentrations of nitrate, dissolved total P (DTP), and TP did not have strong relationship with the distances from the sampling sites to the estuary. Pollution load and water quantity also had an important influence on the concentrations of P in sediments and its interstitial water in estuary sedimentary area.  相似文献   
305.
Ozone continues to be one of the most important air pollution problems in the United States. While significant progress has been made, certain areas of the country still experience unhealthy levels of ozone and are unlikely to achieve current primary standards by 1988. With the prospect of an influx of millions of additional people, and their cars, into these areas by the year 2000, the problem of oxidant regulation and control becomes even greater. From this realization, the Effects Division of the Air Pollution Control Association conceived this conference topic. The summary that follows highlights key issues and findings from the conference held in November 1984 in Houston, Texas. The transactions of the conference will be available from APCA headquarters in the near future.  相似文献   
306.
在海口“望海猩城”生态小区人居环境设计过程中,采有生态设计方法对住宅区内的绿色空间、水资源系统、废弃物处理系统、道路交通系统及建筑空间等进行了规划设计,力求使之形成安全、健康、舒适、高质量、高效益的现代化生态文明住区。  相似文献   
307.
In order to assess the condition of heavy metal pollution in the Yellow River, Lanzhou section, China, and to quantify heavy metal (copper, lead, zinc, and cadmium) contents in tissues (liver, kidney, gills, and muscles) of two fish species (Triplophysa pappenheimi and Gobio hwanghensis), levels of these four metals in the water body, sediment, and tissues of the two fish were measured using inductively coupled plasma-atomic emission spectrometry. The metal levels from this study were compared with the threshold values in the guidelines of water, sediment, and food given by the National Environmental Protection Agency of China, the National Oceanic and Atmospheric Administration of America, and the National Standards Management Department of China. We found the mean concentrations of Cu, Pb, Zn, and Cd in THE water body, sediment, and muscles of two fish species were far below the values in guidelines. We also found that the type of metals present and their concentrations varied in different tissues and species. The results suggested that (1) Cu, Pb, Zn, and Cd did not contaminate the aquatic ecosystem severely and did not threaten the safety of human consumption in the Yellow River, Lanzhou section, and (2) organs that are sensitive to accumulating heavy metals may be useful to develop bioindicators for monitoring metal contamination. Considering environmental variables, further study is necessary before deciding which fish species or tissue could be the ideal bioindicators for aquatic pollution.  相似文献   
308.
测定南京某农药厂附近大米、蔬菜及肉类中11种有机磷农药含量,通过使用气相色谱/质谱联用的方法,建立GC/MS定性定量分析方法,检出限达到0.05μg/kg(肉类)和0.1μg/kg(大米和蔬菜),回收率均符合测定要求。环境样品监测结果显示,大米和蔬菜中有机磷农药的含量高于肉类中的含量,说明在大米和蔬菜表面残留的农药量要高于进入生物体体内的含量。南京蔬菜样品中有机磷农药高于常州蔬菜样品,说明农药厂对蔬菜表面残留农药量有影响。不同的有机磷农药在不同的介质中,检出情况不一样,说明不同的环境介质对有机磷农药的保留水平不一样。  相似文献   
309.
Many regions in China experience air pollution episodes because of the rapid urbanization and industrialization over the past decades. Here we analyzed the effect of emission controls implemented during the G-20 2016 Hangzhou summit on air quality. Emission controls included a forced closure of highly polluting industries, and limiting traffic and construction emissions in the cities and surroundings. Particles with aerodynamic diameter lower than 2.5 μm (PM2.5) and ozone (O3) were measured. We also simulated air quality using a forecast system consisting of the two-way coupled Weather Research and Forecast and Community Multi-scale Air Quality (WRF-CMAQ) model. Results show PM2.5 and ozone levels in Hangzhou during the G-20 Summit were considerably lower than previous to the G-20 Summit. The predicted concentrations of ozone were reduced by 25.4%, whereas the predicted concentrations of PM2.5 were reduced by 56%.  相似文献   
310.
家庭灰尘是人群居住场所的重要环境介质,人群可通过吸入、摄食及皮肤接触等途径摄入灰尘中的污染物,对健康造成一定的损伤。为探索我国西南某矿区周边村庄室内重金属的污染对人群健康的潜在风险,采用2014年3月对我国西南某矿区周边村庄室内灰尘中重金属污染水平调查的数据,结合美国EPA健康风险评价模型对人群健康风险进行分析。结果表明:人群非致癌风险和致癌风险暴露剂量均表现为儿童>成人男性>成人女性,呈现手-口摄食途径>皮肤接触途径>吸入途径,其中儿童、成人男性和成人女性手-口摄食暴露途径占总暴露剂量的98.16%、55.61%和51.5%;儿童以Pb、Cr的暴露为主,成人以Cr的暴露为主;家庭灰尘中单种重金属元素和多途径叠加的非致癌风险在8.81E-03~1.24E-02之间,均小于1,其中儿童以Pb的非致癌风险为主,经手-口摄食暴露占总风险的40%;致癌风险在4.19E-05~3.35E-04之间;A、B、C村儿童的致癌风险均高于US EPA所推荐的可接受水平10-4,其暴露剂量和健康风险均为成人男性和成人女性的5~6倍,且以Cr通过手-口摄食暴露产生的风险最大,占总风险的93%左右。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号