全文获取类型
收费全文 | 1177篇 |
免费 | 8篇 |
国内免费 | 5篇 |
专业分类
安全科学 | 18篇 |
废物处理 | 45篇 |
环保管理 | 70篇 |
综合类 | 691篇 |
基础理论 | 141篇 |
污染及防治 | 172篇 |
评价与监测 | 33篇 |
社会与环境 | 18篇 |
灾害及防治 | 2篇 |
出版年
2017年 | 14篇 |
2015年 | 10篇 |
2014年 | 10篇 |
2013年 | 39篇 |
2012年 | 33篇 |
2011年 | 30篇 |
2010年 | 23篇 |
2009年 | 33篇 |
2008年 | 24篇 |
2007年 | 27篇 |
2006年 | 29篇 |
2005年 | 32篇 |
2004年 | 37篇 |
2003年 | 33篇 |
2002年 | 26篇 |
2001年 | 14篇 |
2000年 | 9篇 |
1998年 | 11篇 |
1995年 | 14篇 |
1994年 | 12篇 |
1993年 | 9篇 |
1989年 | 9篇 |
1978年 | 10篇 |
1966年 | 10篇 |
1965年 | 15篇 |
1964年 | 15篇 |
1963年 | 25篇 |
1962年 | 21篇 |
1961年 | 14篇 |
1960年 | 23篇 |
1959年 | 24篇 |
1958年 | 16篇 |
1957年 | 16篇 |
1956年 | 15篇 |
1955年 | 27篇 |
1954年 | 33篇 |
1953年 | 19篇 |
1952年 | 14篇 |
1951年 | 24篇 |
1948年 | 9篇 |
1947年 | 11篇 |
1943年 | 11篇 |
1941年 | 10篇 |
1939年 | 9篇 |
1938年 | 13篇 |
1935年 | 10篇 |
1933年 | 10篇 |
1931年 | 12篇 |
1930年 | 13篇 |
1929年 | 13篇 |
排序方式: 共有1190条查询结果,搜索用时 15 毫秒
951.
An exploratory field study conducted in Europe and the U.S. examines the challenges of managing environmental quality at the enterprise level. The results show that effective environmental quality management depend to a considerable degree on the ability to deal with the multidisciplinary organizational, technical, social, and cultural issues involved in the integration of environmental cost accounting at the enterprise level. The study suggests that the tools and techniques of modern project management can provide an important framework for developing and implementing environmental quality control systems. The recommendations put considerable emphasis on the human side, focusing on the criteria under which environmental quality is best achievable. Strong senior management leadership, people skills, organizational linkages, and alliances, all are critical for dealing with the complexities of managing responsibly toward sustained developments in today’s organizations. 相似文献
952.
953.
Dietrich von Holst Hans Hutzelmeyer Paul Kaetzke Martin Khaschei Ronald Schönheiter 《Die Naturwissenschaften》1999,86(8):388-393
Wild rabbits of the two sexes have separate linear rank orders, which are established and maintained by intensive fights.
The social rank of individuals strongly influence their fitness: males and females that gain a high social rank, at least
at the outset of their second breeding season, have a much higher lifetime fitness than subordinate individuals. This is because
of two separate factors: a much higher fecundity and annual reproductive success and a 50% longer reproductive life span.
These results are in contrast to the view in evolutionary biology that current reproduction can be increased only at the expense
of future survival and/or fecundity. These concepts entail higher physiological costs in high-ranking mammals, which is not
supported by our data: In wild rabbits the physiological costs of social positions are caused predominantly by differential
psychosocial stress responses that are much lower in high-ranking than in low-ranking individuals.
Received: 23 February 1999 / Accepted: 17 March 1999 相似文献
954.
Marianne Henningsson Malgorzata Blicharska Hans Antonson Grzegorz Mikusiński Görgen Göransson Per Angelstam 《Journal of Environmental Planning and Management》2015,58(4):631-653
The European Landscape Convention indicates that assessment of different dimensions that exist in landscapes should be taken into account in planning. In this study, we first investigated ecological, cultural and social values as perceived by the local people in a highway-planning process in Sweden. Next, we explored which factors influenced the local people's participation in the road-planning process. We used questionnaires, planning documents and the Theory of Planned Behavior to investigate the relations between different factors and local people's participation in the planning process. The results showed that people presumed the ecological values in the landscape to be adversely affected by the new road, while the social values would remain the same. Landowners had heard of the participatory-process, but few participated. Those who lived within 300 m of the road were more active in the planning process than people living further away. The findings suggest that people living within a few hundred metres of the road should be treated as key stakeholders in the planning process. The involvement of other stakeholders, and when in the public participation process stakeholders should be involved, is also discussed. 相似文献
955.
Konstantinos Feidantsis Hans O. P?rtner Antigoni Lazou Basile Kostoglou Basile Michaelidis 《Marine Biology》2009,156(4):797-809
Tolerance to a changing climate regime and persistence in the natural environment depends on the limited capacity to acclimate
to changing temperatures. The present study aimed to identify and characterize thermal limits of the Mediterranean fish Sparus aurata as well as the processes providing heat protection during exposure to high temperatures. Processes studied included heat
shock protein expression, protein kinase activity and metabolic adjustments. Molecular responses were addressed through the
expression of Hsp70 and Hsp90 and the phosphorylation of stress-activated protein kinases, p38 mitogen-activated protein kinase
(p38 MAPK) and cJun-N-terminal kinases (JNKs). Thermal impacts on metabolic capacities were assessed by studying the maximum
activities of citrate synthase (CS), malate dehydrogenase (MDH) and 3-hydroxyacyl CoA dehydrogenase (HOAD) as well as pyruvate
kinase (PK) and lactate dehydrogenase (L-LDH). The expression of Hsp70 and hsp90 was activated when the fish were exposed
to temperatures beyond 20°C. Increased phosphorylation of p38 MAPK and JNKs indicated the parallel activation of MAPK signaling
cascades and the potential involvement of MAPKs in the induction of Hsp genes. Exposure to extreme temperatures beyond 24°C
caused an increase in the enzymatic activity of PK and LDH indicating an enhanced glycolytic potential. 相似文献
956.
957.
958.
Wierrani F Kubin A Loew HG Henry M Spängler B Bodner K Grünberger W Ebermann R Alth G 《Die Naturwissenschaften》2002,89(10):466-469
We report the development of a novel simple experimental method which allows the comparison of new photosensitizers based on their production of reactive oxygen species. A high-performance liquid chromatography (HPLC) assay permits the monitoring of several substances (sensitizer, reactant and oxidized end product) simultaneously on a single chromatogram. Photoreactions were monitored throughout their course by the HPLC assay surveying the sensitizers' efficiency of singlet oxygen production by the oxidative decomposition of luminol. Several photosensitizers were tested: Rose Bengal, Methylene Blue, Protoporphyrin IX, Photosan III, Photofrin, Hypericin and Pseudohypericin. Additionally, photoreactions were monitored by a standard pO2 detection system. The measurements of the two detection methods were strongly correlated. Rose Bengal proved to be the most efficient photosensitizer, clearly decreasing the luminol concentration and causing a corresponding increase in aminophthalic acid. Our experiments show that when factors necessary for photochemical reactions are absent or are blocked (antioxidants), no reaction can be detected. 相似文献
959.
960.
Risk management of chemicals requires information about their adverse effects such as toxicity and persistence, for example. Testing of chemicals allows for improving the information base for regulatory decision‐making on chemicals' production and use. Testing a large number of chemicals with limited time and resources forces a prioritization of chemicals. This paper proposes a decision model that provides a ranking of chemicals according to “urgency to test”. The model adopts a value‐of‐information approach describing the expected welfare gains from regulatory actions that respond to test information. We determine the value‐of‐information of tests revealing chemicals' levels of toxicity and persistence. We compare our findings to the prioritization of chemicals in the new European Chemicals Regulation “REACH”, where several tens of thousands of chemicals are to be tested in order to fill existing information gaps and to implement more effective risk management. We find that the main lines of chemicals' prioritization under REACH receive backing from our decision model. However, prioritization for testing can be further improved by accounting for testing costs and the sensitivity of regulatory action with respect to the test information. 相似文献