全文获取类型
收费全文 | 13667篇 |
免费 | 18篇 |
国内免费 | 54篇 |
专业分类
安全科学 | 86篇 |
废物处理 | 902篇 |
环保管理 | 1662篇 |
综合类 | 1940篇 |
基础理论 | 3967篇 |
环境理论 | 3篇 |
污染及防治 | 2631篇 |
评价与监测 | 1286篇 |
社会与环境 | 1251篇 |
灾害及防治 | 11篇 |
出版年
2022年 | 38篇 |
2021年 | 67篇 |
2020年 | 35篇 |
2019年 | 39篇 |
2018年 | 1523篇 |
2017年 | 1422篇 |
2016年 | 1278篇 |
2015年 | 174篇 |
2014年 | 136篇 |
2013年 | 335篇 |
2012年 | 579篇 |
2011年 | 1493篇 |
2010年 | 804篇 |
2009年 | 747篇 |
2008年 | 1024篇 |
2007年 | 1378篇 |
2006年 | 149篇 |
2005年 | 139篇 |
2004年 | 145篇 |
2003年 | 190篇 |
2002年 | 224篇 |
2001年 | 151篇 |
2000年 | 105篇 |
1999年 | 66篇 |
1998年 | 44篇 |
1997年 | 43篇 |
1996年 | 25篇 |
1995年 | 57篇 |
1994年 | 35篇 |
1993年 | 37篇 |
1992年 | 40篇 |
1991年 | 38篇 |
1990年 | 52篇 |
1989年 | 41篇 |
1988年 | 29篇 |
1987年 | 34篇 |
1986年 | 24篇 |
1985年 | 32篇 |
1984年 | 40篇 |
1983年 | 48篇 |
1982年 | 26篇 |
1981年 | 43篇 |
1980年 | 30篇 |
1979年 | 30篇 |
1977年 | 26篇 |
1976年 | 28篇 |
1975年 | 25篇 |
1970年 | 23篇 |
1967年 | 23篇 |
1965年 | 23篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
3.
4.
5.
E Enan I G Berberian S el-Fiki M el-Masry O H Enan 《Journal of environmental science and health. Part. B》1987,22(2):149-170
Male Baladi rabbits were acutely and sub-chronically intoxicated with cyanofenphos and profenophos. The levels of cholesterol, triglycerides, B-lipoproteins and total proteins were determined in the serum, brain, spinal cord and sciatic nerve of rabbits. Moreover, the activities of alkaline phosphatase, acid phosphatase and glutamic-pyruvic transaminase were determined in the liver of the animals. The whole studies revealed that the biochemical constituents were highly affected by the tested insecticides. Also, the liver function suffered from adverse effects of the tested insecticides. 相似文献
6.
María L. Pignata Martha S. Cañas Hebe A. Carreras Liliana Orellana 《Environmental management》1997,21(5):793-801
Ligustrum lucidum Ait. f. tricolor (Rehd.) Rehd. in relation to atmospheric pollutants in Córdoba city, Argentina. The study area receives
regional pollutants and was categorized taking into account traffic level, industrial density, type of industry, location
of the sample point in relation to the street corner, treeless condition, and topographic level. Dried weight/fresh weight
ratio (DW/FW) and specific leaf area (SLA) were calculated, and concentrations of chlorophylls, carotenoids, total sulfur,
soluble proteins, malondialdehyde (MDA), and hydroperoxy conjugated dienes (HPCD) were determined in leaf samples. Sulfur
content correlates positively with traffic density and SLA correlates negatively with some combinations of the categorical
variables; MDA correlates positively with topographic level and total protein concentration correlates negatively with treeless
condition. On the basis of our results, traffic, location of trees, type of industry, situation of a tree with respect to
others, and topographic level are the environmental variables to bear in mind when selecting analogous sampling points in
a passive monitoring program. An approximation to predict tree injury may be obtained by measuring DW/FW ratio, proteins,
pigments, HPCD, and MDA as they are responsible for the major variability of data. 相似文献
7.
Stin OC Carnahan A Singh R Powell J Furuno JP Dorsey A Silbergeld E Williams HN Morris JG 《Environmental monitoring and assessment》2003,81(1-3):327-336
Molecular methods, including DNA probes, were used to identify and enumerate pathogenic Vibrio species in the Chesapeake Bay; our data indicated that Vibrio vulnificus exhibits seasonal fluctuations in number. Our work included a characterization of total microbial communities from the Bay; development of microarrays that identify and quantify the diversity of those communities; and observation of temporal changes in those communities. To identify members of the microbial community, we amplified the 16S rDNA gene from community DNA isolated from a biofilm sample collected from the Chesapeake Bay in February, 2000. The resultant 75 sequences were 95% or more similar to 7 species including two recently described Shewanella species, baltica and frigidimarina, that have not been previously isolated from the Chesapeake. When the genera of bacteria from biofilm after culturing are compared to those detected by subcloning amplified 16S fragments from community DNA, the cultured sample exhibited a strong bias. In oysters collected in February, the most common bacteria were previously unknown. Based on our 16S findings, we are developing microarrays to detect these and other microbial species in these estuarine communities. The microarrays will detect each species using four distinct loci, with the multiple loci serving as an internal control. The accuracy of the microarray will be measured using sentinel species such as Aeromonas species, Escherichia coli, and Vibrio vulnificus. Using microarrays, it should be possible to determine the annual fluctuations of bacterial species (culturable and non-culturable, pathogenic and non-pathogenic). The data may be applied to understanding patterns of environmental change; assessing the health of the Bay; and evaluating the risk of human illness associated with exposure to and ingestion of water and shellfish. 相似文献
8.
Population characteristics, individual life-history variables, feeding and vertical distribution of the mesopelagic fish Müller's pearlside Maurolicus muelleri collected in 1990 in Masfjorden, western Norway, are reported as well as environmental variables from the fjord. Minimum size at maturity was far smaller than reported from previous investigations in the same region. Fecundity was size-dependent and total egg numbers were higher than reported from other investigations of M. muelleri world wide, while the number of maturing eggs was far lower than observed in the same region earlier. Food concentration in the fjord was an order of magnitude lower than previous early summer observations, and several factors indicated that feeding opportunities may have been low for a long period. Daily feeding rate (g prey g-1 fish) decreased with increasing fish size. These observations fit well with a model of maximizing fitness by means of a flexible size at maturity. Minimum age at maturity seems to be achieved at the expense of fecundity. M. muelleri was concentrated in a 20 to 30 m deep sound scattering layer (SSL). The SSL stayed close to the surface during the night and at 100 to 180 m during the daytime. The vertical position of the SSL varied instantaneously with changes in surface light intensity, remaining at 10-3 to 10-4 mol m-1 s-1 at the top of the SSL. Stomach fullness was highest during the night; feeding intensity seems to have been peaked at dusk. Cladocerans were the main prey ranked by number, copepods by biomass. Intake of large copepods increased with fish size. 相似文献
9.
Pheromones — semiochemicals used by insects for intraspecific chemical communication — can be isolated and with special analytical techniques their chemical structure elucidated. With stereoselective synthesis methods, presented by the preparation of sex attractants and aggregating pheromones of moths and beetles, respectively, a synthetic access to compounds is given which can be used for behavior manipulation of insects. Aside the importance of these compounds for investigations of the sensoric process the possibility of their application in an integrated and biological pest control is discussed. 相似文献
10.