全文获取类型
收费全文 | 1104篇 |
免费 | 16篇 |
国内免费 | 11篇 |
专业分类
安全科学 | 36篇 |
废物处理 | 23篇 |
环保管理 | 171篇 |
综合类 | 403篇 |
基础理论 | 247篇 |
环境理论 | 2篇 |
污染及防治 | 167篇 |
评价与监测 | 35篇 |
社会与环境 | 31篇 |
灾害及防治 | 16篇 |
出版年
2023年 | 10篇 |
2022年 | 12篇 |
2021年 | 26篇 |
2020年 | 13篇 |
2019年 | 29篇 |
2018年 | 21篇 |
2017年 | 37篇 |
2016年 | 31篇 |
2015年 | 21篇 |
2014年 | 20篇 |
2013年 | 65篇 |
2012年 | 39篇 |
2011年 | 37篇 |
2010年 | 36篇 |
2009年 | 32篇 |
2008年 | 44篇 |
2007年 | 34篇 |
2006年 | 37篇 |
2005年 | 28篇 |
2004年 | 30篇 |
2003年 | 21篇 |
2002年 | 31篇 |
2001年 | 21篇 |
2000年 | 12篇 |
1999年 | 17篇 |
1997年 | 8篇 |
1996年 | 7篇 |
1995年 | 10篇 |
1994年 | 9篇 |
1993年 | 10篇 |
1992年 | 10篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 8篇 |
1983年 | 7篇 |
1982年 | 7篇 |
1981年 | 9篇 |
1963年 | 11篇 |
1959年 | 8篇 |
1958年 | 7篇 |
1935年 | 7篇 |
1934年 | 7篇 |
1930年 | 9篇 |
1929年 | 10篇 |
1928年 | 8篇 |
1927年 | 11篇 |
1926年 | 15篇 |
1925年 | 12篇 |
1923年 | 6篇 |
1921年 | 9篇 |
排序方式: 共有1131条查询结果,搜索用时 15 毫秒
91.
92.
The resurgence in the use of wood in the United States for residential heating has been accompanied by a dramatic increase in deaths and injuries from residential fires. Toxic materials present in woodsmoke also appear to present a significant public health hazard. As a result of these factors, production of residential wood heat can be up to two orders of magnitude more hazardous than generation of an equivalent amount of electric energy at a coal-fired power plant. Proper care in installation and operation of wood stoves, as well as technological innovations that control wood-stove emissions, can greatly reduce the health and safety hazards of residential heating with wood. 相似文献
93.
Katja Riedel Rolf Weller Otto Schrems Gert Knig-Langlo 《Atmospheric environment (Oxford, England : 1994)》2000,34(29-30)
The annual cycles of hydrogen peroxide (H2O2) and methylhydroperoxide (MHP) have been investigated at a remote site in Antarctica in order to study seasonal variations as well as chemical processes in the troposphere. The measurements have been performed from March 1997 to January 1998 and in February 1999 at the German Antarctic research station Neumayer which is located at 70°39′S, 8°15′W. The obtained time series for hydrogen peroxide and methylhydroperoxide in near-surface air represents the first all-year measurements in Antarctica and indicates clearly the occurrence of seasonal variations. During polar night mean values of 0.054±0.046 ppbv (range<0.03–0.11 ppbv) for hydrogen peroxide and 0.089±0.052 ppbv (range<0.05–0.14 ppbv) for methylhydroperoxide were detected. At the sunlit period higher Mixing ratios were found, 0.20±0.13 ppbv (range<0.03–0.91 ppbv) for hydrogen peroxide and 0.19±0.10 ppbv (range<0.05–0.89 ppbv) for methylhydroperoxide. Occasional long-range transport of air masses from mid-latitudes caused enhanced peroxide concentrations at polar night. During the period of stratospheric ozone depletion we observed peroxide mixing ratios comparable to typical winter levels. 相似文献
94.
95.
96.
97.
98.
Giant reed for selenium phytoremediation under changing climate 总被引:1,自引:0,他引:1
Hassan R. El-Ramady Neama Abdalla Tarek Alshaal Ahmed S. Elhenawy Mohamed S. Shams Salah E.-D. A. Faizy El-Sayed B. Belal Said A. Shehata Mohamed I. Ragab Megahed M. Amer Miklós Fári Attila Sztrik József Prokisch Dirk Selmar Ewald Schnug Elizabeth A. H. Pilon-Smits Samia M. El-Marsafawy Éva Domokos-Szabolcsy 《Environmental Chemistry Letters》2015,13(4):359-380
99.
100.
Jacob Heilmann‐Clausen Elizabeth S. Barron Lynne Boddy Anders Dahlberg Gareth W. Griffith Jenni Nordén Otso Ovaskainen Claudia Perini Beatrice Senn‐Irlet Panu Halme 《Conservation biology》2015,29(1):61-68
Hitherto fungi have rarely been considered in conservation biology, but this is changing as the field moves from addressing single species issues to an integrative ecosystem‐based approach. The current emphasis on biodiversity as a provider of ecosystem services throws the spotlight on the vast diversity of fungi, their crucial roles in terrestrial ecosystems, and the benefits of considering fungi in concert with animals and plants. We reviewed the role of fungi in ecosystems and composed an overview of the current state of conservation of fungi. There are 5 areas in which fungi can be readily integrated into conservation: as providers of habitats and processes important for other organisms; as indicators of desired or undesired trends in ecosystem functioning; as indicators of habitats of conservation value; as providers of powerful links between human societies and the natural world because of their value as food, medicine, and biotechnological tools; and as sources of novel tools and approaches for conservation of megadiverse organism groups. We hope conservation professionals will value the potential of fungi, engage mycologists in their work, and appreciate the crucial role of fungi in nature. Una Perspectiva Micótica de la Biología de la Conservación 相似文献