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   828篇
  免费   73篇
  国内免费   249篇
安全科学   238篇
废物处理   17篇
环保管理   63篇
综合类   482篇
基础理论   92篇
污染及防治   78篇
评价与监测   34篇
社会与环境   34篇
灾害及防治   112篇
  2024年   4篇
  2023年   13篇
  2022年   27篇
  2021年   45篇
  2020年   51篇
  2019年   40篇
  2018年   31篇
  2017年   28篇
  2016年   41篇
  2015年   60篇
  2014年   55篇
  2013年   61篇
  2012年   77篇
  2011年   94篇
  2010年   61篇
  2009年   66篇
  2008年   48篇
  2007年   51篇
  2006年   36篇
  2005年   35篇
  2004年   29篇
  2003年   14篇
  2002年   14篇
  2001年   14篇
  2000年   7篇
  1999年   17篇
  1998年   12篇
  1997年   14篇
  1996年   18篇
  1995年   13篇
  1994年   21篇
  1993年   10篇
  1992年   5篇
  1991年   10篇
  1990年   4篇
  1989年   1篇
  1988年   2篇
  1987年   4篇
  1986年   4篇
  1985年   6篇
  1984年   2篇
  1979年   1篇
  1978年   1篇
  1975年   1篇
  1972年   1篇
  1967年   1篇
排序方式: 共有1150条查询结果,搜索用时 15 毫秒
991.
危险化学品事故的频繁发生对人民生命财产和环境造成了巨大破坏,对危险化学品生产储存使用全过程实施安全监控和监管是有效减少和预防危化品事故的重要方法和手段.提出了危化品生产储存使用全过程安全监控与监管体系结构,论述了系统建设中进行危险辨识和风险分析的要求,详细讨论了动态安全监控与管理所涉及的采集监测、过程监控、安全分析、预警报警、应急联动、安全管理等主要技术内容及系统功能的设计.所提的技术方法和系统已在石化等企业进行示范应用,取得良好运行效果.  相似文献   
992.
1996年开始发布ISO14000系列标准后,次年我国即等同转化为国家标准。系列标准要求首先在组织内部建立和保持一个符合要求的环境管理体系,通过不断的审核和评价推动运行。标准分为评估组织和评估产品两大系列,其工作的实质内涵一是“改善”,二是“第三者监察”。  相似文献   
993.
Objective: This study aimed at identifying and predicting in advance the point in time with a high risk of a virtual accident before a virtual accident actually occurs using the change of behavioral measures and subjective rating on drowsiness over time and the trend analysis of each behavioral measure.

Methods: Behavioral measures such as neck bending angle and tracking error in steering maneuvering during the simulated driving task were recorded under the low arousal condition of all participants who stayed up all night without sleeping. The trend analysis of each evaluation measure was conducted using a single regression model where time and each measure of drowsiness corresponded to an independent variable and a dependent variable, respectively. Applying the trend analysis technique to the experimental data, we proposed a method to predict in advance the point in time with a high risk of a virtual accident (in a real-world driving environment, this corresponds to a crash) before the point in time when the participant would have encountered a crucial accident if he or she continued driving a vehicle (we call this the point in time of a virtual accident).

Results: On the basis of applying the proposed trend analysis method to behavioral measures, we found that the proposed approach could predict in advance the point in time with a high risk of a virtual accident before the point in time of a virtual accident.

Conclusion: The proposed method is a promising technique for predicting in advance the time zone with potentially high risk (probability) of being involved in an accident due to drowsy driving and for warning drivers of such a drowsy and risky state.  相似文献   

994.
自深圳某污水处理厂曝气池和二沉池的污泥中分离得到2株通过共代谢机制降解直链烷基苯磺酸钠(LAS)的细菌L-2和L-15。通过生理生化和16S rRNA基因序列分析,初步鉴定细菌L-2和L-15分别为Klebsiella sp.和Enterobacter sp.。研究表明:L-2和L-15以LAS作为唯一碳源时,对其降解率仅有1.1%和5.9%。当添加葡萄糖作生长基质,L-2在温度30℃,p H=7.5,m(葡萄糖)∶m(LAS)为20∶1的条件下,对50 mg/L的LAS的降解率可达94.2%;L-15在温度30℃,p H=7.5,m(葡萄糖)∶m(LAS)为16∶1的条件下,对50 mg/L的LAS的降解率可达92.2%。试验结果说明,筛选得到的2株细菌在共代谢的作用下,可以有效地实现废水中LAS降解。  相似文献   
995.
1株兼具好、厌氧汞甲基化能力细菌的分离鉴定   总被引:1,自引:0,他引:1  
陶兰兰  向玉萍  王定勇  黄曼琳  申鸿 《环境科学》2016,37(11):4389-4394
从三峡水库重庆段忠县石宝寨消落带土壤中,分离纯化后获得1株在好氧和厌氧条件下均能将Hg2+转化成甲基汞的细菌,经过对该菌株的形态特征、理化特征检测及16S r DNA序列分析,初步鉴定其为γ-变形菌纲的荧光假单胞菌,并命名为Pseudomonas fluorescens XD-Me Hg-B2(Gen Bank登录号:KU954349).通过汞敏感性试验发现该菌对Hg2+极敏感,汞甲基化试验表明,在初始Hg2+浓度为200 ng·L-1的PBS缓冲液中,接种XD-Me Hg-B2对数生长期菌悬液,有氧条件下,30℃孵育60 min后,溶液中甲基汞浓度呈指数增高,并在160 min时达到最大,约为3.85 ng·L-1±0.33 ng·L-1,最大汞甲基化率为1.93%;而在厌氧条件下,XD-Me Hg-B2同样表现出汞甲基化能力,但其甲基汞的生成较好氧处理显著滞后,且汞甲基化转化率较低,在180min左右甲基汞浓度达到最大,为2.86 ng·L-1±0.73 ng·L-1,最大汞甲基化率为1.43%.综上所述,P.fluorescens XDMe Hg-B2是1株对Hg2+极敏感,兼具好、厌氧汞甲基化能力的细菌,可望为消落带土壤汞生物甲基化的机制研究提供候选菌株,从而为深入研究汞生物地球化学循环、以及正确评价三峡水库蓄水运行后可能带来的汞生态风险评价提供理论依据.  相似文献   
996.
The extant literature on the relationship between self‐sacrificial leadership and subordinate behavioral outcomes has primarily focused on the influence of this leadership on subordinate affiliative behaviors. Our research proposed a theoretical model explaining why and when self‐sacrificial leadership might promote taking charge, an exemplar of challenging behaviors. We tested this model across two studies conducted in China. In addition, we also examined the differences in the boundary conditions for self‐sacrificial leadership to influence taking charge and affiliative behaviors (cooperation in Study 1 and helping in Study 2 ). Our results revealed that (i) self‐sacrificial leadership was positively related to subordinate taking charge, with organizational identification acting as a mediator for this relationship, and (ii) risk aversion moderated both the self‐sacrificial leadership–subordinate taking charge relationship and the mediating effect of organizational identification, such that the relationship and its mediating mechanism were weaker for subordinates high rather than low in risk aversion. These moderating effects, however, could not generalize to cooperation and helping. Finally, the theoretical and practical implications of our results and directions for future research were discussed. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
997.
Objectives: In China, serious road traffic crashes (SRTCs) are those in which there are 10–30 fatalities, 50–100 serious injuries, or a total cost of 50–100 million RMB (U.S.$8–16 M), and particularly serious road traffic crashes (PSRTCs) are those that are more severe or costly. Due to the large number of fatalities and injuries as well as the negative public reaction they elicit, SRTCs and PSRTCs have become of great concern to China during recent years. The aim of this study is to identify the main factors contributing to these road traffic crashes and to propose preventive measures to reduce their number.

Methods: 49 contributing factors of the SRTCs and PSRTCs that occurred from 2007 to 2013 were collected from the database “In-depth investigation and analysis system for major road traffic crashes” (IIASMRTC) and were analyzed through the integrated use of principal component analysis and hierarchical clustering to determine the primary and secondary groups of contributing factors.

Results: Speeding and overloading of passengers were the primary contributing factors, featuring in up to 66.3 and 32.6% of accidents, respectively. Two secondary contributing factors were road related: lack of or nonstandard roadside safety infrastructure and slippery roads due to rain, snow, or ice.

Conclusions: The current approach to SRTCs and PSRTCs is focused on the attribution of responsibility and the enforcement of regulations considered relevant to particular SRTCs and PSRTCs. It would be more effective to investigate contributing factors and characteristics of SRTCs and PSRTCs as a whole to provide adequate information for safety interventions in regions where SRTCs and PSRTCs are more common. In addition to mandating a driver training program and publicization of the hazards associated with traffic violations, implementation of speed cameras, speed signs, markings, and vehicle-mounted Global Positioning Systems (GPS) are suggested to reduce speeding of passenger vehicles, while increasing regular checks by traffic police and passenger station staff and improving transportation management to increase income of contractors and drivers are feasible measures to prevent overloading of people. Other promising measures include regular inspection of roadside safety infrastructure and improving skid resistance on dangerous road sections in mountainous areas.  相似文献   

998.
李开元  邱小秦 《安全》2019,40(2):29-32
为了更好的开展危害辨识,落实有关建立安全生产风险分级管控和隐患排查治理双重预防机制的要求,结合危险源的描述、风险辨识的范围、可能导致的后果、评价分级等环节中普遍存在的问题进行了探讨,讨论了风险辨识与隐患排查治理的关系,同时给出了进一步做好安全风险辨识的建议,表明了安全风险辨识的重要性和长期性。  相似文献   
999.
钢铁企业环境风险重大危险源辨识   总被引:2,自引:0,他引:2  
钢铁企业生产工序复杂,使用的原燃料及各工序产生的副产品也较多,钢铁企业重大危险源辨识,对企业内部降低风险事故发生,减少事故对场界外人群伤害、环境质量恶化及对生态系统影响等具有重要意义。在了解钢铁企业涉及的主要环境风险源的基础上,依据《危险化学品重大危险源辨识》(GB18218-2009),以某钢铁企业为例,根据其风险物质特性及其数量,确定其涉及的环境风险源是否属重大危险源,为环境风险评价等级判断提供依据。  相似文献   
1000.
介绍了以风险辨识、脆弱性分析和应急能力评估相结合的HVC应急管理风险评估法,对石油化工行业的应急管理进行评估的做法。  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