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   1154篇
  免费   56篇
  国内免费   133篇
安全科学   207篇
废物处理   30篇
环保管理   122篇
综合类   466篇
基础理论   155篇
污染及防治   190篇
评价与监测   107篇
社会与环境   46篇
灾害及防治   20篇
  2024年   9篇
  2023年   32篇
  2022年   33篇
  2021年   29篇
  2020年   35篇
  2019年   20篇
  2018年   25篇
  2017年   21篇
  2016年   18篇
  2015年   25篇
  2014年   51篇
  2013年   42篇
  2012年   83篇
  2011年   90篇
  2010年   37篇
  2009年   40篇
  2008年   60篇
  2007年   99篇
  2006年   52篇
  2005年   47篇
  2004年   59篇
  2003年   41篇
  2002年   38篇
  2001年   38篇
  2000年   42篇
  1999年   28篇
  1998年   23篇
  1997年   28篇
  1996年   21篇
  1995年   34篇
  1994年   22篇
  1993年   13篇
  1992年   18篇
  1991年   14篇
  1990年   11篇
  1989年   10篇
  1988年   7篇
  1987年   7篇
  1986年   8篇
  1985年   6篇
  1984年   4篇
  1983年   7篇
  1982年   7篇
  1981年   7篇
  1980年   2篇
排序方式: 共有1343条查询结果,搜索用时 0 毫秒
361.
Aquatic environmental pollution may cause biodiversity loss. Thus, monitoring studies are very important because fish health reflects both quality and sustainability of the environment, as well as of the individuals that live there. In the present report, genetic biomarkers (piscine micronucleus test; comet assay with blood, liver, and kidney cells) were used in specimens of Astyanax sp. to analyze the contamination level of the Cangüiri Farm through biomonitoring. The Cangüiri Farm, the old school farm of the Federal University of Paraná, is inside the Iraí River Environment Preservation Area, created in 1996 to preserve the sources of public water supply in Curitiba and metropolitan area. We verified that the fishes collected within the Cangüiri Farm area presented high damage levels, showing more environment contamination when compared to the specimens collected in the Costa Ecologic Park, used as reference in the present report. The results indicate that the Cangüiri Farm, which is inside an environment protection area, created especially for the protection of the fountainhead for water supply, may be contaminated. These toxic residues, which were remarkably persistent in the environment, are possibly derived from agricultural activities in the wider area. Thus, we suggest the analysis of the area with other biomarkers and for a longer time period.  相似文献   
362.
Concentrations of polychlorinated biphenyls (PCBs) including dioxin-like PCBs (non-ortho, PCB 77, PCB 126, and PCB 169 and mono-ortho, PCB 105, PCB 118, and PCB 156) were measured in different organs and tissues (melon, blubber, liver, kidney, lung, heart, and muscle tissue) of striped dolphins (Stenella coeruleoalba) from the Eastern Mediterranean Sea (Adriatic Sea). The mean highest levels were in blubber and melon, followed by liver, kidney, lung, heart, and muscle tissue. PCB profiles were similar in all tissues and organs being dominated by the higher chlorinated homologues (hexa-CBs, 55.8-62.1%; penta-CBs, 15.4-20.0%; and hepta-CB PCB 180, 12.7-16.5%). Major PCBs in all tissues were congeners 138 and 153 collectively accounting for 50.6-58.3% of the total PCB concentrations, followed by PCB 101, 105, 118, and 180 constituting from 27.0% to 31.0%. PCB levels were higher in adult males than in adult females. The estimated 2,3,7,8-TCDD toxic equivalents of non- and mono-ortho PCBs were much higher than the threshold level above which adverse effects have been observed in other marine mammals species, suggesting that striped dolphins in this region are at risk for toxic effects.  相似文献   
363.
污染场地修复工程环境监理的实践与探索   总被引:1,自引:0,他引:1  
环境监理是污染场地修复过程中不可或缺的关键环节,在我国起步相对较晚,可供借鉴的实例很少。以苏州市某化工厂遗留场地污染土壤和地下水修复工程为例,阐述了不同阶段环境监理的工作内容,突出了原位和异位修复技术的环境监理工作要点,并提出建立污染土壤和地下水修复效果质量控制体系和原位修复效果长期跟踪监测机制等建议。  相似文献   
364.
针对工业场地有机氯污染土壤探索微生物修复的方法,试验表明:添加土著厌氧菌菌液及营养液的试验组,污染物去除率比空白组明显提高。基因测定结果显示,试验土壤中至少存在具有降解有机氯污染物能力的3种菌种。  相似文献   
365.
1998年10月16日《经济参考报》登了一篇揭露北京西客站在施工过程中被腐败蛀虫蛀蚀的报道。报载:青岛电站阀门厂北京供销公司经理苏清福,为销售其从上海、南京、海南、温州等地收购的大量劣质阀门,通过行贿桑塔纳、富康小轿车两辆,现金30多万元,并花了10...  相似文献   
366.
PROBLEM: Although there has been considerable interest in safety climate, relatively little attention has been given to the factors that determine safety climate or to testing the hypothesized mediating role of safety climate with respect to safety-related outcomes. METHOD: Questionnaire responses were obtained from 2,208 employees of a large national retail chain in 21 different locations. RESULTS: After controlling for demographic variables, three factors: environmental conditions, safety-related policies and programs, and general organizational climate, accounted for 55% of the variance in perceived safety climate. Interestingly, organizational climate made a significant contribution to safety climate, even after controlling for the other more safety-relevant variables. Partial correlations showed that safety policies and programs had the largest observed correlation with safety climate, followed by two of the dimensions of organizational climate (communication and organizational support). Using Baron and Kenny's (J. Pers. Soc. Psychol. 51 (1986) 1173) procedures, the principal effects of the various work situation factors on perceived safety at work were found to be direct rather than mediated by safety climate. Safety climate influenced perceived safety at work, but its role as a mediator was limited. IMPACT ON INDUSTRY: These results are discussed in terms of other recent findings on safety climate and the growing interest in understanding management and organizational factors in the context of workplace safety.  相似文献   
367.
8月2日上午,笔者在将乐县看守所见到了"7·29"交通肇事嫌疑人李某。他垂头叹气地对笔者说:想不到我逃走十个小时就给交警逮住了……说着,他神情木然,流下了忏悔的泪水。 现场:疑云密布 扑朔迷离 2004年7月29日21时42分,将乐县交警大队"122"报警电话骤然响起,称在将乐县余坊口路段,一辆  相似文献   
368.
北京东方化工厂“6·27”特大爆炸事故的性质认定在历尽3年零7个月的争执和等待后 ,终于在离新世纪还有15天的时候盖棺论定 :这是一起因操作工开错阀门而导致爆炸的责任事故。我们终于用科学、良知和理性把这个梦魔斩劈在新世纪的门坎之外 ,使之没能让它把晦气带入21世纪。其实 ,这起事故早在3年前就应结案。正是因为一些非正常调查因素的介入 ,才使这起事故迟迟不能结案。1997年8月18日 ,也就是事故发生后的第48天 ,负责调查事故原因的专家组就拿出了事故调查报告 ,以确凿的证据认定这是一起因操作工开错阀门而把本应卸…  相似文献   
369.
为进一步明确碳纤维增强材料(CFRP)加固钢筋混凝土(RC)受弯构件的破坏模式,判断相关规范提出的CFRP许用剥离应变计算公式的正确性,设计并开展钢筋混凝土梁外贴CFRP加固试验,采用2点对称简支加载,探究加固试件的破坏模式和CFRP初始剥离时的应变。结果表明:加固试件的基本破坏模式为CFRP剥离破坏;一些规范规定的许用剥离应变与试验值的比值在0.28~5.12之间,多数规范的许用剥离应变远大于实测值,按规范计算的许用剥离应变的变异系数均大于46%;CFRP的剥离不仅与混凝土强度、CFRP用量和弹性模量有关,还与剪跨比、箍筋配筋率和纵筋配筋率等因素有关。  相似文献   
370.
本文基于中国"陌生人"社会的社会背景下,采用问卷方式对社会各个层次对地震监测预报信息的需求、认知现状等进行了抽样调查,提出了地震监测预报服务社会信息产品的种类及可行性。  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