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   12509篇
  免费   22篇
  国内免费   39篇
安全科学   95篇
废物处理   908篇
环保管理   1511篇
综合类   1416篇
基础理论   3704篇
环境理论   2篇
污染及防治   2595篇
评价与监测   1251篇
社会与环境   1067篇
灾害及防治   21篇
  2023年   30篇
  2022年   100篇
  2021年   121篇
  2020年   61篇
  2019年   54篇
  2018年   1525篇
  2017年   1442篇
  2016年   1308篇
  2015年   205篇
  2014年   145篇
  2013年   220篇
  2012年   608篇
  2011年   1525篇
  2010年   810篇
  2009年   713篇
  2008年   1004篇
  2007年   1332篇
  2006年   97篇
  2005年   147篇
  2004年   200篇
  2003年   220篇
  2002年   201篇
  2001年   91篇
  2000年   48篇
  1999年   36篇
  1998年   24篇
  1997年   26篇
  1996年   19篇
  1995年   24篇
  1994年   18篇
  1993年   10篇
  1992年   12篇
  1991年   18篇
  1990年   9篇
  1989年   11篇
  1988年   5篇
  1987年   10篇
  1986年   8篇
  1985年   10篇
  1984年   21篇
  1983年   17篇
  1982年   5篇
  1981年   7篇
  1979年   8篇
  1975年   3篇
  1970年   3篇
  1966年   3篇
  1964年   4篇
  1961年   3篇
  1935年   3篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
141.
Salinity levels vary spatially in coastal areas, depending on proximity to freshwater sources, and may also be slowly decreasing as a result of anthropogenic climatic changes. The impact of salinity on host–parasite interactions is potentially a key regulator of transmission processes in intertidal areas, where trematodes are extremely common parasites of invertebrates and vertebrates. We investigated experimentally the effects of long-term exposure to decreased salinity levels on output of infective stages (cercariae) and their transmission success in the trematode Philophthalmus sp. This parasite uses the snail Zeacumantus subcarinatus as intermediate host, in which it asexually produces cercariae. After leaving the snail, cercariae encyst externally on hard substrates to await accidental ingestion by shorebirds, which serve as definitive hosts. We found that at reduced salinities (25 or 30 psu), the cercarial output of the parasite was lower, the time taken by cercariae to encyst was longer, fewer cercariae successfully encysted and encysted parasites had lower long-term survival than at normal seawater salinity (35 psu). The strong effect of salinity on the replication and transmission of this parasite suggests that there may be sources and sinks of transmission to birds along coastal areas, depending on local salinity conditions. Also, unless it evolves to adapt to changing conditions, the predicted reduction in salinity as a consequence of climate change may have negative impact on the parasite’s abundance.  相似文献   
142.
Loss of zooxanthellae (dinoflagellate Symbiodinium) from corals will sometimes lead to mass mortality of corals. To detect and quantify Symbiodinium released from corals, we developed a zooxanthellae “trap” and a quantitative PCR (qPCR) system with Symbiodinium clades A–F-specific primer sets. The trap was attached to a branch or the surface of several wild stony corals, and the water samples within the traps, including released Symbiodinium, were subjected to qPCR. All tested corals released clade C Symbiodinium at estimates of ~5,900 cells h−1 cm−2 of coral surface. Although all tested Pocillopora eydouxi harboured both clades C and D, some of these colonies released only clade C or released a lesser amount of clade D than that in the tissues. Our Symbiodinium quantification system revealed that wild hermatypic corals constantly release Symbiodinium to the environment. Our result suggests that some corals may discharge certain clades of Symbiodinium alternatively.  相似文献   
143.
144.
Environmental Science and Pollution Research - For the photocatalytic degradation of antioxidant 2,6-di-tert-butyl-hydroxytoluene (BHT), several TiO2-based composites have been prepared in MWCNT...  相似文献   
145.
Environmental Science and Pollution Research - This paper presents the synthesis of a hybrid material through the use of natural pozzolan and titanium(IV) isopropoxide using the sol-gel method and...  相似文献   
146.
Environmental Science and Pollution Research - The photo-Fenton process was performed with four radiation settings to treat clinical analysis laboratory wastewater (CALWW) from a hospital, with the...  相似文献   
147.
Inclusively delivering the sustainable development goals (SDGs) remains challenging, particularly in urban areas, where some of the most pressing concerns exist. To achieve the transformative SDG agenda, new methods are required to overcome current deficits in engagement around inclusion and equitable outcomes. Evaluating against theories of governance and inclusion, we test a mixture of digital and physical creative methods abilities to deliver co-designed solutions that influence mobility and road safety planning outcomes in East African cities. Greater inclusion led to improved interactions of citizens with decision makers, and the identification of novel, practical solutions, delivering some elements of transformation. Risks include creative methods being used to co-opt communities to official agendas, and institutional planning norms needing to adapt to respond to a wider range of stakeholders. Overall, where risks are mitigated, we recommend that using Creative Methods could localise SDG delivery, ensuring more equitable and effective outcomes from infrastructure development investments.Supplementary InformationThe online version of this article (10.1007/s13280-020-01436-3) contains supplementary material, which is available to authorized users.  相似文献   
148.
Environmental Science and Pollution Research - This work describes the production/characterization of low molar mass chitosan nanoparticles derived from waste shrimp shells (SSC), as well as from a...  相似文献   
149.
Environmental Science and Pollution Research - Animal breeding for meat production based on swine, cattle, poultry, and aquaculture is an activity that generates several impacts on the environment,...  相似文献   
150.
Environmental Science and Pollution Research - Potentially toxic elements (PTEs) are of great concern in steel mill wastes. Therefore, in order to use them as potential fertilizers in soil, risk...  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