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   318篇
  免费   3篇
  国内免费   5篇
安全科学   6篇
废物处理   25篇
环保管理   38篇
综合类   26篇
基础理论   57篇
污染及防治   105篇
评价与监测   52篇
社会与环境   17篇
  2023年   9篇
  2022年   15篇
  2021年   22篇
  2020年   5篇
  2019年   8篇
  2018年   10篇
  2017年   7篇
  2016年   9篇
  2015年   7篇
  2014年   17篇
  2013年   40篇
  2012年   15篇
  2011年   21篇
  2010年   11篇
  2009年   17篇
  2008年   19篇
  2007年   10篇
  2006年   10篇
  2005年   12篇
  2004年   9篇
  2003年   11篇
  2002年   2篇
  2001年   1篇
  2000年   1篇
  1999年   1篇
  1998年   2篇
  1997年   2篇
  1996年   2篇
  1995年   1篇
  1993年   1篇
  1991年   2篇
  1990年   4篇
  1989年   3篇
  1987年   1篇
  1985年   2篇
  1984年   1篇
  1983年   1篇
  1982年   3篇
  1971年   3篇
  1966年   3篇
  1964年   2篇
  1963年   1篇
  1962年   1篇
  1957年   1篇
  1954年   1篇
排序方式: 共有326条查询结果,搜索用时 187 毫秒
211.
212.
213.
Time and again, there has been a hue and a cry that the world is running out of natural resources and the most prominent among those is the famous study entitled ‘The Limits to Growth’ by the ‘Club of Rome’. Since then the fear of scarcity of abiotic resources has been challenging human societies around the globe, particularly the research community. In this paper we will examine the case of the steel industry to argue how and why mineral resources depletion is an issue that needs to be addressed through life cycle assessment in more detail. This paper shows that a more comprehensive understanding about the current production trends of iron ore and steel, which also requires several vital metals such as copper, manganese, nickel and so on, can provide useful insights in assessing the potential future threat of shortages due to depletion of abiotic mineral resources.  相似文献   
214.
Metal pollution produces damage to marine organisms at the cellular level possibly leading to ecological imbalance. The present investigation focused on the acute and chronic toxicity of lead (Pb) and zinc (Zn) by examining the effects of biomarker enzymes in post-larvae of Penaeus monodon (Tiger prawn). Antioxidant biomarker responses such as lipid peroxidation (LPO) and catalase (CAT) activity for Pb and Zn were determined following chronic exposure. Acute Lethal Concentration 50 (LC50) values observed in the study at 96?h for Pb and Zn at 5.77?±?0.32?mg?L?1 and 3.02?±?0.82?mg?L?1, respectively. The estimated No Observed Effect Concentration and Lowest Observed Effect Concentration values for Pb were 0.014 and 0.029?mg?L?1 and that recorded for Zn was 0.011 and 0.022?mg?L?1, respectively. Among the two metals studied, toxicity of Zn was found to be greater to P. monodon than Pb. The activities of antioxidant defense enzymes and total protein content differed significantly from control following exposure to both metals. Overall, the biomarker studies demonstrated that alterations in antioxidant enzymes and induction of LPO reflect the consequences of heavy metal exposure in P. monodon.  相似文献   
215.
Monthly collections of the clam Paphia malabarica were made for period of 1 year from May 2002 to April 2003 from Verem, Mandovi estuary, Goa. Clams were categorised into two groups, 25-35 mm (small size) and 35-40 mm (big size). Significant difference was not observed in the accumulation of metals in the whole soft tissue between the two size groups. Irrespective of size, annual mean, metal content recorded as microg/g dry weight in the whole soft tissue was 3.8, 30.3, 13.5, 36.6 and 105.7, respectively, for Cd, Pb, Cu, Zn and Fe. Of the two toxic elements Cd and Pb, Cd content was almost uniform throughout the year except for a rise in September for the small size and October for the big size. Pb, on the other hand, was low from the beginning of the monsoon and exhibited distinct accumulation from December onwards up to April, May and, to some extent, June. The pattern was similar in both the size groups, the values being higher for the bigger size group. The three essential elements Cu, Fe and Zn exhibit trends similar to one another with peaks in September and December-January in both the size groups. Cadmium accumulation was highest in the mantle and adductor muscle, Lead, in foot, Copper, in digestive gland and gonad, and Zn and Fe, in gills. Correlation coefficient between different metal couplings as tested statistically revealed significant coupling for Zn-Fe (r 0.92) in the bigger size group, the same was observed between Cu-Fe (r 0.62) and Cd-Zn (r 0.94). Seasonal difference in Pb accumulation was highly significant.  相似文献   
216.
The emergence of China as a global player challenges the pre-existing dominance of the OECD countries and will continue to be a crucial force for global change in coming decades. The implications of China’s rise will be most significant for low- and middle-income countries, but the outcomes will also affect China’s relations with traditional donors and the understanding of the process of development. While these issues are increasingly explored at the political and economic level, very little analysis is available for the environmental impacts that China has on low- and middle-income countries. It is well understood that China plays a major role in relation to climate change, energy use and natural resource use at the global level; however, the perspective of China’s environmental impacts on low- and middle-income countries is underexplored. This Special Issue, therefore, elaborates the rise of China from the environmental perspective and assesses the impacts of China’s rise on low- and middle-income countries for international research, policy and practice in the field of environment and development. The findings draw on insights relevant for energy, water, forestry and land issues in Asia, Africa and Latin America.  相似文献   
217.
Drawing upon empirical data collected in China and Africa, this article evaluates Chinese overseas corporate social responsibility strategies and their effectiveness in mitigating environmental impacts in parts of Africa. China’s enhanced role within the global economy has profound environmental implications for the world. In particular, China has rapidly expanded its environmental footprint in Africa, largely because of its burgeoning economic presence through trade and aid projects such as infrastructure and public works. These large-scale projects, commonly managed by state-owned enterprises (SOEs), tend to be in sectors that are environmentally sensitive such as oil and gas exploration and construction of major infrastructure. At the international level, global financial institutions along with growing pressure from civil society organizations are encouraging China to demonstrate a commitment to addressing the environmental impacts of its overseas projects. At the domestic level, growing awareness of such issues has generated an emerging trend of Chinese entities promoting and adopting corporate social responsibility (CSR) initiatives. These moves seek to improve the environmental and social impacts of Chinese overseas investments. However, research has shown that the outcomes of Chinese overseas CSR strategies (particularly in environmental protection) vary widely due to the operating procedures of the Chinese SOEs in combination with specific local political and social structures. In general, environmental protection is weak and so there is a need for the Chinese and African governments to create a legislative and institutional framework to address Chinese investment in Africa especially in the area of natural resource extraction.  相似文献   
218.
Chemical process safety was not a major public concern prior to 1984. As far as chemical hazards were concerned, public fears focused on disease (cancer) and environmental degradation. Even a series of major process incident tragedies did not translate into widespread public concerns about major incidents in chemical plants that might disastrously affect the public. This situation changed completely after the December 1984 disaster at the Union Carbide plant in Bhopal. Not only was the public's confidence in the chemical industry shaken, the chemical industry itself questioned whether its provisions for protection against major incidents were adequate.

The recognition of the need for technical advances and implementation of management systems led to a number of initiatives by various stakeholders throughout the world. Governments and local authorities throughout the world initiated regulatory regimes. Has all that has resulted from the legacy of Bhopal reduced the frequency and severity of incidents? How can we answer this question? As we move into more and more globalization and other complexities what are the challenges we must address? According to the authors, some of these challenges are widespread dissemination and sharing of lessons learned, risk migration because of globalization, changing workforce, and breakthroughs in emerging areas in process safety.  相似文献   

219.
220.
Toxic or hazardous substances pose two types of risks in the environment, namely `short-term or acute risk' and `long-termor chronic risk'. The short-term risk is associated with the one-time acute exposure to potentially hazardous substancesaccidentally released in the environment, whereas the long-termrisk is resulted from continuous exposure to potentially harmfulsubstances present in different environmental media. This articledeals with the assessment of potential health risks related to certain carcinogens and non-carcinogens (e.g. cadmium, chromiumand nickel) present in three environmental media, viz. air, waterand food in different Indian states (regions). Appropriate dose-response models have been identified and used for this purpose with the assumptions and input data as per the Indian context. Mean values of ambient air concentration levels of Cd,Cr and Ni have been used to estimate the individual and societalrisks of extra cancer in different states of India. The hazardquotients and hazard index representing the non-carcinogenic chronic health effects caused by chromium and cadmium due to their long-term exposure through water and food have also beenestimated. The risk results have been compared with the diseasesurveillance data. A definite correlation between the estimatedrisk results and the reported number of lung cancer cases and chronic liver diseases have been observed in different regions. As a matter of fact, it is not possible to derive precise risk estimates due to various uncertainties included both in availabledata and in the models which are used to calculate potency factors and effective concentration. However, average risk levelsas estimated and presented in this article are quite useful forplanning purposes.  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