全文获取类型
收费全文 | 19171篇 |
免费 | 167篇 |
国内免费 | 123篇 |
专业分类
安全科学 | 397篇 |
废物处理 | 750篇 |
环保管理 | 2022篇 |
综合类 | 4825篇 |
基础理论 | 4349篇 |
环境理论 | 13篇 |
污染及防治 | 4758篇 |
评价与监测 | 1149篇 |
社会与环境 | 1146篇 |
灾害及防治 | 52篇 |
出版年
2022年 | 130篇 |
2021年 | 135篇 |
2019年 | 134篇 |
2018年 | 268篇 |
2017年 | 262篇 |
2016年 | 391篇 |
2015年 | 305篇 |
2014年 | 443篇 |
2013年 | 1226篇 |
2012年 | 478篇 |
2011年 | 772篇 |
2010年 | 569篇 |
2009年 | 646篇 |
2008年 | 788篇 |
2007年 | 811篇 |
2006年 | 719篇 |
2005年 | 595篇 |
2004年 | 610篇 |
2003年 | 598篇 |
2002年 | 592篇 |
2001年 | 686篇 |
2000年 | 443篇 |
1999年 | 328篇 |
1998年 | 218篇 |
1997年 | 238篇 |
1996年 | 258篇 |
1995年 | 269篇 |
1994年 | 271篇 |
1993年 | 239篇 |
1992年 | 227篇 |
1991年 | 238篇 |
1990年 | 227篇 |
1989年 | 196篇 |
1988年 | 185篇 |
1987年 | 174篇 |
1986年 | 174篇 |
1985年 | 168篇 |
1984年 | 185篇 |
1983年 | 182篇 |
1982年 | 194篇 |
1981年 | 164篇 |
1980年 | 145篇 |
1979年 | 137篇 |
1978年 | 149篇 |
1977年 | 137篇 |
1976年 | 122篇 |
1975年 | 121篇 |
1974年 | 133篇 |
1967年 | 128篇 |
1965年 | 122篇 |
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
1.
Russian Journal of Ecology - The dynamics of the species richness, breeding density, and structure of the community of birds occupying nest-boxes upon a 50-fold reduction of atmospheric emissions... 相似文献
2.
3.
4.
Maheswari C. Ramya A. S. Priya B. Meenakshi Sudhahar S. Prabhu Raj B. Lokesh B. Ramani G. 《Journal of Material Cycles and Waste Management》2021,23(6):2255-2265
Journal of Material Cycles and Waste Management - The present research work focused on fabricating Biodegradable Plate (BD plate) composed of rice husk ash, bagasse and corn starch which is... 相似文献
5.
Quantitative methods have been applied to the study of floristic structure and diversity in Samarskaya Luka. The results show that Samarskaya Luka is a floristically heterogeneous area in which six elementary floras can be distinguished. This area has been assessed as a floristically autonomous formation, and its floristic representativeness was estimated. 相似文献
6.
F. Pricope Ştefănescu G. Tiţescu I. Cărăuş D. Ureche 《Environmental Chemistry Letters》2003,1(2):149-151
During the artificial reproduction of salmonides, the fecundity can be increased either by improving the viability of spermatozoa,
or by extending the time period during which a roe micropile remains open, thus allowing its fecundation. Practically, this
can be achieved by the use of some fertilising techniques suitable for fish species. Here, we show that the reproduction of
rainbow trout in a 1:1 solution of deuterium-depleted water and distilled water led to a significant increase in survival
of roes during their embryonic development. Moreover, the addition of glucose and fructose into the deuterium-depleted fertilising
solutions led to a further increase in roe survival during embryonic development. The increase in survival is mainly explained
by an increase in the motility of spermatozoa. 相似文献
7.
G G Pyle S M Swanson D M Lehmkuhl 《Environmental pollution (Barking, Essex : 1987)》2002,116(2):243-255
Elevated concentrations of arsenic, nickel, and molybdenum in aquatic systems around northern Saskatchewan uranium mines are an environmental concern. Early life stage fathead minnows were used to assess toxicity from several aquatic systems near the Key Lake and Rabbit Lake uranium operations. Hatching success of fish embryos exposed to waters receiving contaminants associated with uranium ore milling was reduced by 32-61% relative to controls. Mortality differed in two lakes receiving mill effluents because of opposing factors influencing metal toxicity (i.e. low pH and high hardness). In one mill receiving water (Fox Lake), larval mortality was 0%, whereas mortality was 85% in water collected from a downstream location (Unknown Lake). Fish embryos exposed to open-pit dewatering effluent receiving waters, or water from a flooded open pit (i.e. pit waters), hatched 26-39% earlier than those exposed to reference or control water. The combination of low water hardness and elevated nickel concentrations in pit waters contributed to the early hatching. Egg hatchability and hatching time were more sensitive indicators of toxicity than 'standard' endpoints, like larval mortality and growth. Current regulatory emphasis on single contaminants and standard toxicological endpoints should be re-evaluated in light of the complex interaction among confounding variables such as pH, hardness. conductivity, and multi-metal mixtures. 相似文献
8.
9.
10.
Frank Eierdanz Joseph Alcamo Lilibeth Acosta-Michlik Dörthe Krömker Dennis Tänzler 《Regional Environmental Change》2008,8(4):197-205
This paper presents the technical aspects of a new methodology for assessing the susceptibility of society to drought. The
methodology consists of a combination of inference modelling and fuzzy logic applications. Four steps are followed: (1) model
input variables are selected—these variables reflect the main factors influencing susceptibility in a social group, population
or region, (2) fuzzification—the uncertainties of the input variables are made explicit by representing them as ‘fuzzy membership
functions’, (3) inference modelling—the input variables are used to construct a model made up of linguistic rules, and (4)
defuzzification—results from the model in linguistic form are translated into numerical form, also through the use of fuzzy
membership functions. The disadvantages and advantages of this methodology became apparent when it was applied to the assessment
of susceptibility from three disciplinary perspectives: Disadvantages include the difficulty in validating results and the
subjectivity involved with specifying fuzzy membership functions and the rules of the inference model. Advantages of the methodology
are its transparency, because all model assumptions have to be made explicit in the form of inference rules; its flexibility,
in that informal and expert knowledge can be incorporated through ‘fuzzy membership functions’ and through the rules in the
inference model; and its versatility, since numerical data can be converted to linguistic statements and vice versa through
the procedures of ‘fuzzification’ and ‘defuzzification’. 相似文献