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   13848篇
  免费   43篇
  国内免费   17篇
安全科学   82篇
废物处理   1028篇
环保管理   1490篇
综合类   1651篇
基础理论   3934篇
环境理论   5篇
污染及防治   3188篇
评价与监测   1387篇
社会与环境   1131篇
灾害及防治   12篇
  2023年   47篇
  2022年   142篇
  2021年   132篇
  2020年   54篇
  2019年   62篇
  2018年   1550篇
  2017年   1449篇
  2016年   1376篇
  2015年   248篇
  2014年   279篇
  2013年   467篇
  2012年   717篇
  2011年   1576篇
  2010年   876篇
  2009年   750篇
  2008年   1095篇
  2007年   1443篇
  2006年   239篇
  2005年   175篇
  2004年   161篇
  2003年   173篇
  2002年   194篇
  2001年   79篇
  2000年   57篇
  1999年   43篇
  1998年   23篇
  1997年   15篇
  1996年   10篇
  1995年   28篇
  1994年   19篇
  1993年   14篇
  1992年   11篇
  1991年   10篇
  1990年   13篇
  1984年   12篇
  1983年   16篇
  1970年   13篇
  1967年   10篇
  1966年   12篇
  1965年   17篇
  1964年   28篇
  1963年   12篇
  1962年   17篇
  1961年   14篇
  1960年   13篇
  1959年   29篇
  1958年   32篇
  1957年   18篇
  1956年   15篇
  1955年   19篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
181.
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   
182.
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   
183.
184.
Environmental Science and Pollution Research - The most common mycotoxin found in European foodstuffs, especially unprocessed grains, is deoxynivalenol (DON), which inhibits proteosynthesis and...  相似文献   
185.
Environmental Science and Pollution Research - The order Odonata has been regularly used as an indicator of the ecosystem’s condition. The objective of this review was to analyze the...  相似文献   
186.
Environmental Science and Pollution Research - In this work, the activated persulfate oxidation of ciprofloxacin (CIP) using a low-grade titanium ore under sunlight or simulated sunlight were...  相似文献   
187.
Environmental Science and Pollution Research - Banana is one of the most important agricultural products of Ecuador. It relies on intensive monoculture cropping systems with a large volume of...  相似文献   
188.
Environmental Science and Pollution Research - Nowadays, the use of different nanoscale structures has been introduced to a large number of research areas. One of these is the treatment and...  相似文献   
189.
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   
190.
Environmental Science and Pollution Research - Environmental arsenic exposure in adults and children has been associated with a reduction in the expression of club cell secretory protein (CC16) and...  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