全文获取类型
收费全文 | 4321篇 |
免费 | 30篇 |
国内免费 | 24篇 |
专业分类
安全科学 | 43篇 |
废物处理 | 168篇 |
环保管理 | 140篇 |
综合类 | 1963篇 |
基础理论 | 769篇 |
环境理论 | 7篇 |
污染及防治 | 878篇 |
评价与监测 | 242篇 |
社会与环境 | 150篇 |
灾害及防治 | 15篇 |
出版年
2022年 | 52篇 |
2021年 | 39篇 |
2019年 | 33篇 |
2018年 | 69篇 |
2017年 | 57篇 |
2016年 | 75篇 |
2015年 | 65篇 |
2014年 | 97篇 |
2013年 | 192篇 |
2012年 | 127篇 |
2011年 | 95篇 |
2010年 | 118篇 |
2009年 | 127篇 |
2008年 | 146篇 |
2007年 | 167篇 |
2006年 | 114篇 |
2005年 | 106篇 |
2004年 | 93篇 |
2003年 | 114篇 |
2002年 | 89篇 |
2001年 | 86篇 |
2000年 | 84篇 |
1999年 | 84篇 |
1998年 | 58篇 |
1997年 | 53篇 |
1996年 | 35篇 |
1995年 | 51篇 |
1994年 | 52篇 |
1991年 | 36篇 |
1990年 | 41篇 |
1985年 | 36篇 |
1979年 | 38篇 |
1978年 | 33篇 |
1977年 | 32篇 |
1969年 | 35篇 |
1968年 | 32篇 |
1967年 | 55篇 |
1966年 | 47篇 |
1965年 | 53篇 |
1964年 | 62篇 |
1963年 | 62篇 |
1962年 | 58篇 |
1961年 | 63篇 |
1960年 | 55篇 |
1959年 | 64篇 |
1958年 | 59篇 |
1957年 | 69篇 |
1956年 | 49篇 |
1955年 | 49篇 |
1954年 | 46篇 |
排序方式: 共有4375条查询结果,搜索用时 886 毫秒
981.
982.
983.
984.
Jürgen Franzaring 《Environmental Sciences Europe》1997,9(2):69-75
Results of an ozone-biomonitoring program performed from May to October 1994 at five different stations on exposed Bel W3 tobacco plants in the southwest of Germany (region of Trier) are presented. No linear dose-response relationship could be deduced between ambient ozone concentration and leaf necroses. Gas-exchange rates of tobacco plants during typical summer days would have to be determined to evaluate the stomatal uptake of photo-oxidant gases. Nevertheless, monitoring with the aid of Bel W3 tobacco plants permits an evaluation of qualitative differences in the ambient ozone concentrations. More severe leaf damage were clearly related to periods with higher radiation and was consequently found more frequently in sites located at higher altitudes. Microclimatic differences, however, may also be responsible in part for the ozone-related leaf damage seen at these sites. For this reason, only general conclusions concerning the relative levels of pollution can be deduced from biomonitoring studies using the reactivity of the indicator plant, which strongly restricts the reliability of such field studies. Pigment levels and leaf patterns in tobacco plants which still demonstrate no necrosis cannot be used as early ozone indicators. 相似文献
985.
986.
987.
988.
Jürgen Kranz 《Die Naturwissenschaften》1985,72(8):419-426
989.
990.
The main objective of this paper was to analyse the present status of medical waste management in the Trachea region of Turkey and subsequently to draw up a policy regarded with generation, collection, on-site handling, storage, processing, recycling, transportation and safe disposal of medical wastes. This paper also presents the results of study about awareness on how to handle expired drugs. Initially all health-care establishments in Tekirda?, Edirne and Kyrklareli provinces in Trachea region were identified and the amounts of hospital wastes generated by each of them were determined. Current medical waste-management practices, including storage, collection, transportation and disposal, in surveyed establishments were identified. Finally, according to results, remedial measurements for medical waste management in these establishments were suggested. Unfortunately, medical wastes are not given proper attention and these wastes are disposed of together with municipal and industrial solid wastes. The current disposal method is both a public health and environmental hazard. When landfill sites are visited, many scavengers can be seen sorting for recyclable materials, a practice which is dangerous for the scavengers. In addition, it was found that some staff in health-care establishments are unaware of the hazard of medical wastes. It is concluded that a new management system, which consists of segregation, material substitution, minimization, sanitary landfilling and alternative medical waste treatment methods should be carried out. For the best appropriate medical waste management system, health-care establishment employers, managers and especially the members of house- keeping divisions should be involved in medical waste management practice. 相似文献