全文获取类型
收费全文 | 93527篇 |
免费 | 1234篇 |
国内免费 | 1144篇 |
专业分类
安全科学 | 3816篇 |
废物处理 | 3376篇 |
环保管理 | 14401篇 |
综合类 | 21218篇 |
基础理论 | 26702篇 |
环境理论 | 73篇 |
污染及防治 | 16143篇 |
评价与监测 | 5618篇 |
社会与环境 | 3971篇 |
灾害及防治 | 587篇 |
出版年
2022年 | 817篇 |
2021年 | 823篇 |
2020年 | 653篇 |
2019年 | 875篇 |
2018年 | 1182篇 |
2017年 | 1231篇 |
2016年 | 2197篇 |
2015年 | 1827篇 |
2014年 | 2581篇 |
2013年 | 9254篇 |
2012年 | 2308篇 |
2011年 | 2689篇 |
2010年 | 3320篇 |
2009年 | 3480篇 |
2008年 | 2278篇 |
2007年 | 2191篇 |
2006年 | 2517篇 |
2005年 | 2397篇 |
2004年 | 2746篇 |
2003年 | 2569篇 |
2002年 | 2104篇 |
2001年 | 2461篇 |
2000年 | 2081篇 |
1999年 | 1535篇 |
1998年 | 1379篇 |
1997年 | 1373篇 |
1996年 | 1494篇 |
1995年 | 1602篇 |
1994年 | 1494篇 |
1993年 | 1344篇 |
1992年 | 1351篇 |
1991年 | 1312篇 |
1990年 | 1269篇 |
1989年 | 1220篇 |
1988年 | 1067篇 |
1987年 | 994篇 |
1986年 | 998篇 |
1985年 | 1075篇 |
1984年 | 1164篇 |
1983年 | 1183篇 |
1982年 | 1183篇 |
1981年 | 1101篇 |
1980年 | 948篇 |
1979年 | 943篇 |
1978年 | 828篇 |
1977年 | 729篇 |
1976年 | 646篇 |
1974年 | 629篇 |
1973年 | 661篇 |
1972年 | 677篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
131.
132.
133.
M. Marcelli M. Caburazzi A. Perilli V. Piermattei E. Fresi 《Chemistry and Ecology》2005,21(5):351-367
The towed undulating vehicle (TUV), named SARAGO, was used for two fine-scale surveys between the Italian and the Sardinian coasts during the Astraea 2 cruise (6-7 and 26-27 September 1995), studying the deep chlorophyll maximum distribution. SARAGO sections identify a sub-surface doming with higher chlorophyll a and primary production concentrations in the upwelling area of a cyclonic gyre region, detected by sea-surface temperature images. In the first section, the cyclone presents a double doming, in density and salinity, with shallower and concentrated patches of chlorophyll a for about 2 miles. Twenty days later, the second section shows that the gyre changes shape and extension, showing a single doming with higher primary production and chlorophyll a concentrations, distributed over a large area of about 40 nautical miles. SARAGO allows analysis of this high-variability phenomenon (cyclonic gyre) and allows concentrated patches (2 nm) to be identified, thus proving the importance of TUVs in the study of mesoscale processes. 相似文献
134.
135.
136.
JOSEPH P. DUDLEY 《Conservation biology》1995,9(5):1332-1334
137.
138.
Bruce C. Glavovic 《Journal of Environmental Planning and Management》1996,39(4):483-506
Protected areas in developing countries play a vital role in promoting the ideal of sustainable development.But 'people-park'conflicts are commonplace,threatening the future of these areas and the long term well-being of local communities. Surprisingly, little attention has been given to applying lessons learned in conflict studies to people-parkconflicts. In contrast to traditional adversarialresponses, negotiated approaches offer considerable potential for transforming people-park conflicts into mutually beneficial relationships.Experiencesin the Richtersveldregion of South Africa demonstrate the cardinal role negotiation can play in addressing key issues underlying people-park conflicts. 相似文献
139.
Risk homeostasis theory postulates that people accept a specific level (target level) of risk in a given activity in return for benefits accruing from that activity. It follows that, if people expect a great deal from the future, the less likely they are to jeopardise it by taking risks in respect of their health and safety. One effective method for reducing target level of risk are incentives, and the available literature contains ample evidence of the effectiveness of incentives programmes in accident prevention. As incentives essentially imply an enhanced quality of life in the future, the question arises as to how expectations of the future may be related to health and safety habits. In order to explore the relationship between perceived value of the future and health and safety habits, an analysis of the psychological literature on individual differences in future time orientation/perspective is presented. Four factors are identified: (1) clear ideation of the future, (2) active planning for the future, (3) time pressure, and (4) optimistic expectations about events outside one's own control. It is hypothesised that factors (1) and (2) are associated with positive health and safety habits, while factors (3) and (4) may characterise individuals with relatively high target levels of physical risk. Research questions and procedures for the study of these relationships are discussed. 相似文献
140.