全文获取类型
收费全文 | 230篇 |
免费 | 0篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 1篇 |
废物处理 | 10篇 |
环保管理 | 7篇 |
综合类 | 111篇 |
基础理论 | 47篇 |
污染及防治 | 32篇 |
评价与监测 | 8篇 |
社会与环境 | 15篇 |
出版年
2021年 | 2篇 |
2018年 | 3篇 |
2016年 | 4篇 |
2015年 | 3篇 |
2013年 | 5篇 |
2012年 | 4篇 |
2011年 | 10篇 |
2010年 | 2篇 |
2009年 | 9篇 |
2008年 | 5篇 |
2007年 | 10篇 |
2006年 | 7篇 |
2005年 | 9篇 |
2004年 | 4篇 |
2003年 | 2篇 |
2002年 | 6篇 |
2001年 | 2篇 |
1999年 | 6篇 |
1998年 | 2篇 |
1997年 | 6篇 |
1996年 | 5篇 |
1995年 | 6篇 |
1994年 | 8篇 |
1993年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1989年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1975年 | 3篇 |
1970年 | 2篇 |
1966年 | 8篇 |
1965年 | 4篇 |
1964年 | 11篇 |
1963年 | 7篇 |
1962年 | 5篇 |
1961年 | 9篇 |
1959年 | 3篇 |
1958年 | 2篇 |
1957年 | 2篇 |
1956年 | 3篇 |
1955年 | 4篇 |
1954年 | 7篇 |
1940年 | 1篇 |
1939年 | 2篇 |
1935年 | 1篇 |
1934年 | 1篇 |
1932年 | 1篇 |
1930年 | 2篇 |
排序方式: 共有231条查询结果,搜索用时 15 毫秒
111.
112.
113.
While it is widely known that sustainable development is the only sound and viable pathway for humankind’s future, its attainment remains elusive despite intensive efforts and some successes. The current industrial society approach based on product and process innovation in a variety of fields is not providing the expected results in addressing this important issue. In an attempt to carry out this unavoidable task, Osaka University’s Research Institute for Sustainability Science (RISS) introduces an integral and dynamic innovation system where technology plays a key role in fulfilling societal functions. This innovation system adopts a highly solution-driven approach that makes use of backcasting techniques based on long-term visions and mid-term strategic goals. Since technology management is the key to propelling effective innovation towards sustainability, we propose a technology transition management through the interaction of technology push, demand pull and institutional design, along with eight transition principles. RISS will develop this innovation system based on these three components and through the design of dynamic scenarios and their roadmaps. 相似文献
114.
Simone Gingrich Karl-Heinz Erb Fridolin Krausmann Veronika Gaube Helmut Haberl 《Regional Environmental Change》2007,7(1):37-47
This article presents a comprehensive data set on Austria’s terrestrial carbon stocks from the beginnings of industrialization
in the year 1830 to the present. It is based on extensive historical and recent land use and forestry data derived from primary
sources (cadastral surveys) for the early nineteenth century, official statistics available for later parts of the nineteenth
century as well as the twentieth century, and forest inventory data covering the second half of the twentieth century. Total
carbon stocks—i.e. aboveground and belowground standing crop and soil organic carbon—are calculated for the entire period
and compared to those of potential vegetation. Results suggest that carbon stocks were roughly constant from 1830 to 1880
and have grown considerably from 1880 to 2000, implying that Austria’s vegetation has acted as a carbon sink since the late
nineteenth century. Carbon stocks increased by 20% from approximately 1.0 GtC in 1830 and 1880 to approximately 1.2 GtC in
the year 2000, a value still much lower than the amount of carbon terrestrial ecosystems are expected to contain in the absence
of land use: According to calculations presented in this article, potential vegetation would contain some 2.0 GtC or 162%
of the present terrestrial carbon stock, suggesting that the recent carbon sink results from a recovery of biota from intensive
use in the past. These findings are in line with the forest transition hypothesis which claims that forest areas are growing
in industrialized countries. Growth in forest area and rising carbon stocks per unit area of forests both contribute to the
carbon sink. We discuss the hypothesis that the carbon sink is mainly caused by the shift from area-dependent energy sources
(biomass) in agrarian societies to the largely area-independent energy system of industrial societies based above all on fossil
fuels. 相似文献
115.
116.
Kerstin?E.?ThonhauserEmail author Shirley?Raveh Attila?Hettyey Helmut?Beissmann Dustin?J.?Penn 《Behavioral ecology and sociobiology》2013,67(12):1961-1970
Females often show multi-male mating (MMM), but the adaptive functions are unclear. We tested whether female house mice (Mus musculus musculus) show MMM when they can choose their mates without male coercion. We released 32 females into separate enclosures where they could choose to mate with two neighboring males that were restricted to their own territories. We also tested whether females increase MMM when the available males appeared unable to exclude intruders from their territories. To manipulate territorial intrusion, we introduced scent-marked tiles from the neighboring males into males' territories, or we rearranged tiles within males' own territories as a control. Each female was tested in treatment and control conditions and we conducted paternity analyses on the 57 litters produced. We found that 46 % of litters were multiply sired, indicating that multiple paternity is common when females can choose their mates. Intrusion did not increase multiple paternity, though multiple paternity was significantly greater in the first trial when the males were virgins compared to the second trial. Since virgin male mice are highly infanticidal, this finding is consistent with the infanticide avoidance hypothesis. We also found that multiple paternity was higher when competing males showed small differences in their amount of scent marking, suggesting that females reduce MMM when they can detect differences in males' quality. Finally, multiple paternity was associated with increased litter size but only in the intrusion treatment, which suggests that the effect of multiple paternity on offspring number is dependent on male–male interactions. 相似文献
117.
Helmut Haenel 《Die Naturwissenschaften》1954,41(15):362-362
118.
119.
120.
Helmut Metzner 《Die Naturwissenschaften》1973,60(11):507-515