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   143篇
  免费   2篇
  国内免费   4篇
安全科学   30篇
环保管理   34篇
综合类   59篇
基础理论   7篇
污染及防治   6篇
评价与监测   7篇
社会与环境   2篇
灾害及防治   4篇
  2021年   1篇
  2017年   2篇
  2016年   2篇
  2015年   1篇
  2014年   5篇
  2013年   6篇
  2012年   5篇
  2011年   12篇
  2010年   7篇
  2009年   12篇
  2008年   8篇
  2007年   9篇
  2006年   19篇
  2005年   8篇
  2004年   6篇
  2003年   7篇
  2002年   9篇
  2001年   10篇
  2000年   5篇
  1999年   2篇
  1998年   3篇
  1997年   2篇
  1995年   1篇
  1994年   1篇
  1992年   2篇
  1991年   2篇
  1990年   2篇
排序方式: 共有149条查询结果,搜索用时 468 毫秒
121.
突发事故危害期估算模式研究   总被引:4,自引:0,他引:4       下载免费PDF全文
针对大气环境突发事故造成的危害,在高斯扩散模式基础上,引入危害半径变化与时间及危害期变化与横风向距离呈线性关系的假设,得出危险源附近各处受危险源突发事故危害的危害时间长短(危害期)一系列定量估算公式,使用方便,结果精确,为环境风险评价提供了有效的工具,可广泛应用于环境风险评价与管理、风险工程设计、风险责任保险等各个领域与事故应急计划制定、事故抢险工作实施.  相似文献   
122.
高温矿井空调冷负荷计算   总被引:1,自引:0,他引:1  
空调冷负荷的计算是高温矿井采用人工制冷的关键 ,从几个方面讨论了它的计算方法。  相似文献   
123.
锡矿山粉尘的危害与防治   总被引:1,自引:0,他引:1  
介绍了锡矿山矿务局粉尘危害的情况和采取的防治措施 ,提醒人们对粉尘危害应重视  相似文献   
124.
The St. Johns River Water Management District (SJRWMD) has developed a minimum flows and levels (MFLs) method that has been applied to rivers, lakes, wetlands, and springs. The method is primarily focused on ecological protection to ensure systems meet or exceed minimum eco-hydrologic requirements. MFLs are not calculated from past hydrology. Information from elevation transects is typically used to determine MFLs. Multiple MFLs define a minimum hydrologic regime to ensure that high, intermediate, and low hydrologic conditions are protected. MFLs are often expressed as statistics of long-term hydrology incorporating magnitude (flow and/or level), duration (days), and return interval (years). Timing and rates of change, the two other critical hydrologic components, should be sufficiently natural. The method is an event-based, non-equilibrium approach. The method is used in a regulatory water management framework to ensure that surface and groundwater withdrawals do not cause significant harm to the water resources and ecology of the above referenced system types. MFLs are implemented with hydrologic water budget models that simulate long-term system hydrology. The method enables a priori hydrologic assessments that include the cumulative effects of water withdrawals. Additionally, the method can be used to evaluate management options for systems that may be over-allocated or for eco-hydrologic restoration projects. The method can be used outside of the SJRWMD. However, the goals, criteria, and indicators of protection used to establish MFLs are system-dependent. Development of regionally important criteria and indicators of protection may be required prior to use elsewhere.  相似文献   
125.
随着工业生产、城市建设以及交通运输的迅速发展,噪声对人们产生的危害日益加剧,尤其以相关行业的职工患有噪声职业病为主.详细阐述了噪声职业病的各种危害,并根据相关法律标准,结合现今噪声领域前沿研究人员提出的噪声控制方法,对预防和控制噪声职业病提出了一些科学、系统的安全措施和防范对策.  相似文献   
126.
水葫芦繁殖过度的危害及其防治措施   总被引:14,自引:0,他引:14  
主要介绍了水葫芦的生物学特性及利用途径 ,分析了水葫芦繁殖过度的原因与危害性 ,并提出了防治措施。  相似文献   
127.
浅谈汽车尾气与人体健康   总被引:2,自引:0,他引:2  
在介绍汽车尾气的组成以及污染现状,同时阐述了汽车尾气对儿童和成年人的危害,并结合国内外的研究状况将汽车尾气对人体的危害作了总结和展望.  相似文献   
128.
持久性有机污染物的危害及防治对策   总被引:6,自引:0,他引:6  
持久性有机污染物(persistent organic pollutants简称POPs)具有致癌、致突变和致畸变作用,对人类健康造成严重危害.本文就POPs的定义、特征、主要来源、种类及对人类健康的危害进行了阐述,提出了防治对策及建议.  相似文献   
129.
实验室常见化学废弃物的危害及处理   总被引:1,自引:0,他引:1  
论述了实验室几种常见废弃物的危害及处理方法,指出了废弃物必须经过有效处理,才能利于环境保护,防止意外事故发生。  相似文献   
130.
The growth, development and consumption of successive three generations of cotton bollworm, Helicoverpa armigera (Htibner), fed on cotton bolls grown under elevated CO2 (double-ambient vs. ambient) in open-top chambers were examined. Significant decreases in protein, total amino acid, water and nitrogen content and increases in free fatty acid were observed in cotton bolls. Changes in quality of cotton bolls affected the growth, development and food utilization of H. armigera. Significantly longer larval development duration in three successive generations and lower pupal weight of the second and third generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower fecundity was also found in successive three generations of H. armigera fed on cotton bolls grown under elevated CO2. The consumption per larva occurred significant increase in successive three generations and frass per larva were also significantly increased during the second and third generations under elevated CO2. Significantly lower relative growth rate, efficiency of conversion of ingested food and significant higher relative consumption rate in successive three generations were observed in cotton bollworm fed on cotton bolls grown under elevated CO2. Significantly lower potential female fecundity, larval numbers and population consumption were found in the second and third generations of cotton bollworm fed on cotton bolls grown under elevated CO2. The integrative effect of higher larval mortality rate and lower adult fecundity resulted in significant decreases in potential population consumption in the latter two generations. The results show that elevated CO2 adversely affects cotton bolls quality, which indicates the potential population dynamics and potential population consumption of cotton bollworm will alleviate the harm to the plants in the future rising CO2 atmosphere.  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