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   1202篇
  免费   61篇
  国内免费   426篇
安全科学   59篇
废物处理   84篇
环保管理   99篇
综合类   610篇
基础理论   221篇
污染及防治   457篇
评价与监测   73篇
社会与环境   47篇
灾害及防治   39篇
  2024年   4篇
  2023年   11篇
  2022年   49篇
  2021年   39篇
  2020年   30篇
  2019年   48篇
  2018年   40篇
  2017年   53篇
  2016年   53篇
  2015年   86篇
  2014年   103篇
  2013年   130篇
  2012年   106篇
  2011年   98篇
  2010年   84篇
  2009年   74篇
  2008年   108篇
  2007年   82篇
  2006年   61篇
  2005年   53篇
  2004年   50篇
  2003年   46篇
  2002年   39篇
  2001年   29篇
  2000年   26篇
  1999年   29篇
  1998年   26篇
  1997年   22篇
  1996年   22篇
  1995年   16篇
  1994年   13篇
  1993年   14篇
  1992年   12篇
  1991年   9篇
  1990年   4篇
  1989年   2篇
  1988年   5篇
  1987年   1篇
  1986年   1篇
  1985年   3篇
  1983年   3篇
  1982年   1篇
  1981年   2篇
  1977年   1篇
  1956年   1篇
排序方式: 共有1689条查询结果,搜索用时 578 毫秒
721.
Environmental Science and Pollution Research - Sleep problems are common in modern society and may be related to environmental chemicals. The objective of this study is to investigate the...  相似文献   
722.
723.
与其预防性政策相一致,法国钢铁联盟(FFA)已经到2000年使其CO2比排放量比1990年削减15%,并使总排放量削减10%.FFA的这项志愿协议是Usinor公司在可持续发展范畴内的前瞻性环境保护思路的代表.本文叙述了FFA签署该志愿协议背后的故事,和该协议的基本原则,也论述了另外一些可以探讨的实现可持续发展的道路.  相似文献   
724.
Zhang  Min  Shan  Shengdao  Chen  Yonggen  Wang  Fang  Yang  Deyi  Ren  Jikai  Lu  Haoyu  Ping  Lifeng  Chai  Yanjun 《Environmental geochemistry and health》2019,41(1):43-52
Environmental Geochemistry and Health - Cadmium (Cd)-contaminated rice (Oryza sativa) in Southern China is a great threat to food security, and the paddy soil remediation is urgently needed to...  相似文献   
725.
The paper is concerned with biohydrometallurgical methods of cadmium recovery from spent Ni–Cd batteries. Cd leaching efficiency from electrode material in different media (H2SO4 and Fe2(SO4)3 solutions), at different Fe(III) concentrations and using the bacteria Acidithiobacillus ferrooxidans were investigated. The main aim of this study was to understand which from the bioleaching products (sulphuric acid or ferric sulphate) play a main role in the bioleaching process of Cd recovery. The influence of Fe ions on Cd leachability was confirmed. The best leaching efficiency of Cd (100%) was reached by bioleaching and also by leaching in Fe2(SO4)3 solution. The results of X-ray diffraction confirmed that no cadmium was present in solid residuum obtained after the Cd bioleaching as well as Cd leaching using solely ferric iron. The use of H2SO4 solution resulted in the lowest efficiency of Cd leachability, the presence of hydroxides in electrode materials caused neutralization of the leaching solution and inhibition of Cd leaching.  相似文献   
726.
Samples of gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs) were collected at three sampling stations (Xiaomai Island, Laohutan, and Zhangzi Island) in the north Yellow Sea, China during November 2008 and September 2009 to study their atmospheric transport potential and the gas/particle distributions. The composition of PAHs was dominated by gaseous compounds. The percentages of the particle-phase PAHs to the total concentrations were found to be higher during the heating period than the non-heating period. The ratios of naphthalene and acenaphthene to phenanthrene, chrysene and dibenzo(a,h)anthracene showed an increasing trend from Xiaomai Island to Zhangzi Island, which can be called as the local atmospheric distillation of PAHs. Gas/particle partitioning coefficients (K p) and their relationship with the sub-cooled liquid vapor pressures (pºL) of PAHs were investigated. The regressions of logK p versus logpºL gave significant correlations for all samples of the three sites with r 2 values in the range 0.56–0.66 (p?<?0.01). Both Junge–Pankow adsorption model and octanol–air partition coefficient absorption model tended to underestimate the sorption for most PAHs, but the absorption model appeared to be more suitable for predicting the particle fraction of PAHs than the Junge–Pankow model.  相似文献   
727.
为通过计算机技术低成本的、高效的、准确的解决建筑火灾安全问题,对计算机技术在建筑结构火灾安全上的综合应用进行研究,并以某一小学教学楼为例将应用成果进行展示。首先,通过FDS软件对该建筑某火灾场景进行了火场数值模拟。基于FDS的数据,利用RCFire程序进行了结构构件内部温度计算和结构火灾反应计算。最后,在Vega的虚拟现实平台上将构件内部温度和结构火灾反应的结果进行了动态图形展示,并实现了结构火灾反应的同步漫游。本文将建筑火场模拟技术、结构火灾反应计算技术和场景表现技术上综合应用到同一建筑上,形成了一个更为准确的结构火灾反应模拟系统,同时也为进一步的建筑火灾场景仿真奠定了基础。  相似文献   
728.
传统的资源学目前正面临着知识经济的挑战。为适应知识经济的要求,传统的资源学应在研究内容、研究方法及学科观念上进行创新  相似文献   
729.
Abstract

Based on the formation process of the Loess Plateau, the characteristics comparison between loess and ancient soil and the located materials of spore- pollen, ancient stone artifact, history, geography and soil erosion, the analysis reveals that the present state serious soil erosion in Loess Plateau, instead of being a natural geologic course, is a consequence of destruction of vegetation, irrational land utilization and the direct destruction of soil permeability and anti-erosion ability, esp. anti-scourability. The water and soil conservation measures, with the twenty-eight-word amelioration principle as the core, are the basis for exploiting and improving water and soil resources of the Loess Plateau so as to harness the Huanghe (the Yellow River).  相似文献   
730.
Abstract

Over the past decade, the Chinese government has developed several plans regulations and policy measures related to the development of renewable energy technologies and has implemented a series of pilot projects. Chinese policymakers have spent several years studying how renewable energy policy models that have been used internationally could be implemented in China. Programs are currently underway to implement pilot renewable portfolio standards, or mandatory market shares (MMS) for renewable energy, in several provinces. This paper examines the primary institutions that are involved in promoting renewable policies in China, the structure of the policies that currently are being drafted, and the status of the complementary, national-level renewable energy law being drafted to provide a legal basis for ongoing local and national-level policies. It then examines the legal requirements for promoting renewable energy legislation under the Chinese law-making system. Finally, it provides recommendations for strategies to ensure the smooth implementation of a multi-faceted national renewable energy policy and legal framework.  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