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   73篇
  免费   1篇
  国内免费   26篇
安全科学   4篇
废物处理   4篇
环保管理   6篇
综合类   40篇
基础理论   13篇
污染及防治   29篇
评价与监测   2篇
社会与环境   2篇
  2022年   3篇
  2021年   1篇
  2020年   2篇
  2019年   5篇
  2018年   3篇
  2017年   4篇
  2016年   6篇
  2015年   4篇
  2014年   3篇
  2013年   7篇
  2012年   15篇
  2011年   9篇
  2010年   4篇
  2009年   3篇
  2008年   6篇
  2007年   5篇
  2006年   2篇
  2005年   1篇
  2003年   3篇
  2001年   1篇
  2000年   2篇
  1998年   4篇
  1997年   4篇
  1996年   1篇
  1991年   1篇
  1979年   1篇
排序方式: 共有100条查询结果,搜索用时 15 毫秒
31.
探讨了有机物特性及中间产物H2O2在催化臭氧化中的作用。结果表明,有机物在自由基链反应过程中的特性直接影响催化臭氧化的降解效率。当目标有机物是对链反应具有促进作用的甲酸时,自由基引发反应可以明显提高甲酸的臭氧化效率。当目标有机物是对自由基链反应具有抑制剂作用的乙酸时,O3和Fe2+/O3对乙酸有着相似的降解效率。以上结果表明,自由基引发反应并不是臭氧化降解效率提高的充分条件。另外,当臭氧化过程有H2O2产生时,必须考虑类Fenton反应对臭氧化效率的影响。  相似文献   
32.
33.
Anthropogenic Calcium Particles Observed in Beijing and Qingdao, China   总被引:2,自引:0,他引:2  
Analysis of individual particles collected at Beijing in northern China revealed that particles abundant in calcium (Ca) always constituted a large fraction of mineral particles in the urban atmosphere. The particles were characterized by cubic morphologies. The major mineral element in the particles was Ca and few or no other mineral elements were detected. A large number of the particles were in the range of diameter <1 μm, where common natural mineral particles were rarely detected. The contribution of the Ca particles to the volume of total mineral particles greatly exceeded that of other mineral particles during non-dust-storm periods and was comparable to that during dust-storm periods. Reagent film tests showed that particulate sulfate and nitrate formation on the Ca particles was similar to that on common mineral particles. These results indicate that a large portion of Ca in the atmospheric particulate matter in Beijing was from anthropogenic sources rather than from natural sources, and the anthropogenic Ca particles acted as a significant medium for the formation of sulfate and nitrate. Similar particles were also detected at Qingdao, a coastal city in northern China. Data of a dust storm event showed that Ca-abundant particles from East China arrived there and moved out of the continent, similarly to Asian dust storm particles, suggesting possible contributions of anthropogenic Ca even in Asian dust storm samples in the downstream areas. Therefore, Ca may not be a good indicator of Asian dust from natural sources. However, the Ca particles, due to their unique shapes and elemental compositions, may provide an indicator for the atmospheric dispersion of anthropogenic particulate matters in East Asia.  相似文献   
34.
The chemical composition of persistent organic pollutants (POPs) in the environment is not uniform throughout the world, and these contaminants contain many structurally different lipophilic compounds. In a well-defined study cohort in the Slovak Republic, the POP chemicals present in the peripheral blood of exposed children were chemically analyzed. The chemical analysis data revealed that the relative concentration and profile of structurally different organic pollutants, including polychlorinated biphenyls (PCBs), 2,2′-bis(4-chlorophenyl)-1,1-dichloroethylene (p,p′-DDE), 2,2′-bis(4-chlorophenyl)-1,1,1-trichloro-ethane (p,p′-DDT), hexachlorobenzene (HCB) and β-hexachlorocyclohexane (β-HCH), may vary from individual to individual, even within the same exposure area. These chemicals can be broadly classified into two groups. The first group, the PCB congeners, primarily originated from industrial compounds and their byproducts. The second group of compounds originated from or was commonly used in the agricultural sector (e.g., DDT, HCB). The objective of this study was to examine the effects of the two POP exposure profiles on gene expression. For the study population, we selected pre-pubertal girls (mean age of 46.2 ± 1.4 months) with high POP concentrations in their blood (> 75% tile of total POP) and classified them in the high ‘PCB’ group when the total PCB concentration was significantly higher than the total concentration of other POP components and in the ‘Other Than PCB’ (OTP) group, when the total PCB concentration was significantly lower than the concentration of the other major POP constituents. A matched control group of girls (< 25% tile of total POP) was selected for comparison purpose (n = 5 per group). Our aims were to determine whether there were any common effects of high POP exposure at a toxicogenomic level and to investigate how exposure may affect physiological functions of the children in two different exposure scenarios. Global gene expression analysis using a microarray (Affymetrix Gene Chip Human genome U133 Plus 2.0 Array) platform was conducted on the total RNA of peripheral blood mononuclear cells from the girls. The results were analyzed by Partek GS, Louis, MI, which identified twelve genes (ATAD2B, BIVM, CD96, CXorf39, CYTH1 ETNK1, FAM13A, HIRA, INO80B, ODG1, RAD23B, and TSGA14) and two unidentified probe sets, as regulated differentially in both the PCB and OTP groups against the control group. The qRT-PCR method was used to validate the microarray results. The Ingenuity Pathway Analysis (IPA) software package identified the possible molecular impairments and disease risks associated with each gene set. Connective tissue disorders, genetic disorders, skeletal muscular disorders and neurological diseases were associated with the 12 common genes. The data therefore identified the potential molecular effects of POP exposure on a genomic level. This report underscores the importance of further study to validate the results in a random population and to evaluate the use of the identified genes as biomarkers for POP exposure.  相似文献   
35.
宋薇  臧海龙  张峰  刘长青  毕学军 《环境工程》2013,(Z1):307-309,328
以青岛市某规模化养鸡场冲洗废水为研究对象,考察以"A/O生化+混凝沉淀+MBBR(Moving Bed Biofilm Reactor)氧化"三段式处理工艺处理该类废水达标排放的可行性。试验结果表明:A/O生化段可以有效去除废水中有机污染物,COD的去除率可达92.86%,出水COD浓度可以达到DB 37534—2005《山东省畜禽养殖业污染物排放标准》第三阶段要求;对BOD5、SS、氨氮及TP去除效率分别可以达到90.81%、89.04%、68.42%及80.79%,但出水尚达不到排放标准要求。混凝沉淀可以有效去除废水中SS及TP,处理后出水浓度分别为44 mg/L及2.26 mg/L,可以达到排放标准要求;经济有效的混凝剂为聚合硫酸亚铁,最优投加量为15 mg/L。MBBR氧化对BOD5及氨氮有着较好的去除效果,水力停留时间8 h时BOD5及氨氮出水浓度分别为42 mg/L及19.40 mg/L,出水可以达到排放标准要求。  相似文献   
36.
普光气田环境空气植物监测体系的初步构想   总被引:1,自引:0,他引:1  
在简要回顾国内外有关植物监测大气污染研究的基础上,针对普光气田主要大气污染因子与环境监测现状,从监测植物筛选、监测点位选取、监测体系标准化、"植物-大气-土壤"综合评价系统以及应急监测机制等五个方面,讨论了构建该地区环境空气植物监测体系的基本想法和建议,并进行了展望,供项目建设决策参考。  相似文献   
37.
根据黑龙江省水资源和水源地概况,提出了体系构成原则,建立了饮用水水源地技术保障体系。研究成果可为黑龙江省饮用水水源地环境保护工作的开展提供技术支撑。  相似文献   
38.
无铅焊料合金中重金属元素浸出行为的研究   总被引:1,自引:0,他引:1  
赵杰  孟宪明  陈忱  臧华勋  马海涛 《环境科学》2008,29(8):2341-2344
选用Sn.3.5Ag-0.5Cu、Sn-3.5Ag、Sn-0.5Cu无铅焊料合金及它们与Cu的钎焊接头,研究了它们在典型的酸性、碱性和盐溶液中的重金属元素的浸出规律.结果表明,焊料合金中的主要浸出元素Sn在酸性或碱性溶液中的浸出量都不是太多,而在NaCl盐溶液中浸出量增大2个数量级.制备成钎焊接头后,在酸性环境中,Sn-3.5Ag和Sn.0.5Cu钎焊接头中Sn的浸出量增加1个数量级以上,而在NaOH碱性环境中.Sn-3.5Ag-0.5Cu钎焊接头中Sn的浸出量相对较高.该结果对电子垃圾填埋环境选择及相关决策提供了参考.  相似文献   
39.
The thermally activated persulfate (PS) degradation of carbon tetrachloride (CT) in the presence of formic acid (FA) was investigated. The results indicated that CT degradation followed a zero order kinetic model, and CO 2 · was responsible for the degradation of CT confirmed by radical scavenger tests. CT degradation rate increased with increasing PS or FA dosage, and the initial CT had no effect on CT degradation rate. However, the initial solution pH had effect on the degradation of CT, and the best CT degradation occurred at initial pH 6. Cl had a negative effect on CT degradation, and high concentration of Cl displayed much strong inhibition. Ten mmol·L–1HCO 3 promoted CT degradation, while 100 mmol·L1NO 3 inhibited the degradation of CT, but SO 4 2– promoted CT degradation in the presence of FA. The measured Cl–concentration released into solution along with CT degradation was 75.8% of the total theoretical dechlorination yield, but no chlorinated intermediates were detected. The split of C-Cl was proposed as the possible reaction pathways in CT degradation. In conclusion, this study strongly demonstrated that the thermally activated PS system in the presence of FA is a promising technique in in situ chemical oxidation (ISCO) remediation for CT contaminated site.  相似文献   
40.
Currently, environmental protection and resources conservation continue to be challenges faced by solid-waste managers in China. These challenges are being further compounded by rapid socioeconomic devel- opment and population growth associated with increased waste generation rates and decreased waste disposal capacities. In response to these challenges, an interval joint-probabilistic mixed-integer programming (IJMP) method is developed for supporting long-term planning of waste management activities in the city of Tianjin, which is one of the largest municipalities in the northern part of China. In the IJMP, joint probabilistic constraints are introduced into an interval-parameter mixed-integer programming framework, such that uncertainties presented in terms of interval values and random variables can be reflected. Moreover, a number of violation levels for the waste-management-capacity constraints are examined, which can facilitate in-depth analyses of tradeoffs among economic objective and system-failure risk. The results indicate that reasonable solutions have been generated. They are valuable for supporting the adjustment of the city's existing waste-management practices and the long- term planning of the city's waste-management facilities.  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