全文获取类型
收费全文 | 297篇 |
免费 | 12篇 |
国内免费 | 30篇 |
专业分类
安全科学 | 65篇 |
废物处理 | 2篇 |
环保管理 | 59篇 |
综合类 | 103篇 |
基础理论 | 36篇 |
污染及防治 | 15篇 |
评价与监测 | 51篇 |
社会与环境 | 5篇 |
灾害及防治 | 3篇 |
出版年
2023年 | 10篇 |
2022年 | 3篇 |
2021年 | 18篇 |
2020年 | 17篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 12篇 |
2016年 | 12篇 |
2015年 | 16篇 |
2014年 | 26篇 |
2013年 | 18篇 |
2012年 | 8篇 |
2011年 | 28篇 |
2010年 | 8篇 |
2009年 | 20篇 |
2008年 | 19篇 |
2007年 | 10篇 |
2006年 | 14篇 |
2005年 | 12篇 |
2004年 | 5篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 3篇 |
1998年 | 4篇 |
1997年 | 9篇 |
1996年 | 5篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1983年 | 1篇 |
1979年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有339条查询结果,搜索用时 15 毫秒
281.
Neal R. Haddaway 《Ambio》2014,43(5):703-706
Much of the scientific literature in existence today is based on model systems and case studies, which help to split research into manageable blocks. The impact of this research can be greatly increased in meta-analyses that combine individual studies published over time to identify patterns across studies; patterns that may go undetected by smaller studies and that may not be the main subject of investigation. However, many potentially useful studies fail to provide sufficient data (typically means, true sample sizes, and measures of variability) to permit meta-analysis. Authors of primary research studies should provide these summary statistics as a minimum, and editors should require them to do so. By putting policies in place that require these summary statistics to be included, or even those that require raw data, editors and authors can maximize the legacy and impact of the research they publish beyond that of their initial target audience. 相似文献
282.
Hugo José Oliveira Zoffoli Carlos Alberto Alves Varella Nelson Moura Brasil do Amaral-Sobrinho Everaldo Zonta Alfredo Tolón-Becerra 《Chemosphere》2013
In environmental monitoring, variables with analytically non-detected values are commonly encountered. For the statistical evaluation of these data, most of the methods that produce a less biased performance require specific computer programs. In this paper, a statistical method based on the median semi-variance (SemiV) is proposed to estimate the position and spread statistics in a dataset with single left-censoring. The performances of the SemiV method and 12 other statistical methods are evaluated using real and complete datasets. The performances of all the methods are influenced by the percentage of censored data. In general, the simple substitution and deletion methods showed biased performance, with exceptions for L/2, Inter and L/√2 methods that can be used with caution under specific conditions. In general, the SemiV method and other parametric methods showed similar performances and were less biased than other methods. The SemiV method is a simple and accurate procedure that can be used in the analysis of datasets with less than 50% of left-censored data. 相似文献
283.
284.
Lihua Pang Qianhui Lin Shasha Zhao Hao Zheng Chenguang Li Jing Zhang Cuizhu Sun Lingyun Chen Fengmin Li 《Frontiers of Environmental Science & Engineering》2023,17(8):94
285.
Eco-Efficiency of Electric and Electronic Appliances: A Data Envelopment Analysis (DEA) 总被引:2,自引:0,他引:2
Y. Barba-Gutiérrez B. Adenso-Díaz S. Lozano 《Environmental Modeling and Assessment》2009,14(4):439-447
Several papers have studied the eco-efficiency of manufacturing systems to address strategic socioeconomic issues in the context
of sustainability analysis. Their goal has been to take into account not only environmental impact aspects throughout the
whole life cycle but also to incorporate the associated economic value as well, thus, giving a comprehensive vision of both
factors. This paper focuses on different commonplace household electric appliances, comparing their eco-efficiency computed
using a data envelopment analysis model. We consider the retail price as a measure of the product’s economic value and the
ecopoint LCA score as the assessment of its environmental impact. We conclude that cell phones and the bulky analyzed appliances
have the highest eco-efficiency scores, whereas the rest would require a more environmentally friendly redesign and/or an
increase in their perceived value to improve their eco-efficiency. 相似文献
286.
Governance of water supply systems in the Palestinian Territories: A data envelopment analysis approach to the management of water resources 总被引:2,自引:0,他引:2
This study demonstrates that data envelopment analysis (DEA) can be a useful tool to assess the relative efficiencies of water supply systems and to establish benchmarks with which to measure progress in the management of water resources. Frontier efficiency models measure the efficiency of water use in the Palestinian Territories (West Bank and the Gaza Strip). At the municipality level, sufficient data for the years 1999-2002 were available to estimate efficiency and stability scores. The Gaza Strip efficiency scores were considerably lower than those of the West Bank. Water losses were the major source of the inefficiency as indicated by the large slacks of this input. The relative sizes of the municipalities affect efficiency scores little. Palestinian policy makers should focus on rebuilding the infrastructure of the water networks, beginning with the most DEA inefficient municipalities in order to minimize water losses. 相似文献
287.
夏晓玲 《环境监测管理与技术》2014,26(6):63-66
阐述了上海市环境空气自动监控数据采集系统的发展历程,介绍了系统的应用功能,分析了其在管理方式、运行维护、应用扩展等环节存在的问题。建议制定数据采集系统的维护管理与考核制度,统一数据来源与数据使用规则;推广电子化管理,加强突发异常情况的维护;增加仪器状态参数的报警功能及站房环境与门禁系统的监控,丰富现场点检内容,建立可视化运维平台,保障系统平稳运行。 相似文献
288.
多源环境监测信息交换模型的设计与实现 总被引:2,自引:0,他引:2
针对环境监测系统现有的污染源管理、饮用水管理、噪声管理、自动监测管理等信息系统存在异构化、多源化等现象,造成数据重复录入、数据不一致、资源浪费等问题,展示了一种数据交换模型的设计思路和实现方法,介绍模型的数据抽取、数据封装、数据传递、数据解析、数据映射、校验和转换、数据接收等多个环节。该数据交换模型已成功实现与多个外部业务系统数据对接,现每天采集的数据超过5 000条,系统运行稳定、性能良好。 相似文献
289.
无锡市MODIS气溶胶光学厚度与PM_(2.5)质量浓度的相关性分析 总被引:1,自引:0,他引:1
将MODIS数据反演得出的气溶胶光学厚度与无锡市区实测得到的PM2.5质量浓度进行相关性分析,结果两者的直接相关性较低,相关系数为0.283 4。气溶胶光学厚度经垂直分布和湿度修正后,两者相关性显著提高,相关系数为0.565 9。虽然修正过程存在误差,相关性未达预期程度,但该方法得到的气溶胶光学厚度可作为PM2.5监测的有效补充。 相似文献
290.
对新型区域γ辐射监测系统的组成和功能进行介绍,详细分析剂量仪、数据收发器和上位机软件的设计。将该系统用于涉核场所核辐射的监测,运行测试结果正常,表明该系统具有功耗低和自组网的特点,能适用于区域γ辐射监测。 相似文献