全文获取类型
收费全文 | 5494篇 |
免费 | 477篇 |
国内免费 | 492篇 |
专业分类
安全科学 | 693篇 |
废物处理 | 93篇 |
环保管理 | 807篇 |
综合类 | 2316篇 |
基础理论 | 430篇 |
污染及防治 | 259篇 |
评价与监测 | 1558篇 |
社会与环境 | 102篇 |
灾害及防治 | 205篇 |
出版年
2024年 | 22篇 |
2023年 | 95篇 |
2022年 | 158篇 |
2021年 | 155篇 |
2020年 | 223篇 |
2019年 | 142篇 |
2018年 | 129篇 |
2017年 | 155篇 |
2016年 | 203篇 |
2015年 | 261篇 |
2014年 | 313篇 |
2013年 | 371篇 |
2012年 | 404篇 |
2011年 | 414篇 |
2010年 | 308篇 |
2009年 | 311篇 |
2008年 | 213篇 |
2007年 | 323篇 |
2006年 | 305篇 |
2005年 | 287篇 |
2004年 | 215篇 |
2003年 | 277篇 |
2002年 | 172篇 |
2001年 | 167篇 |
2000年 | 153篇 |
1999年 | 114篇 |
1998年 | 90篇 |
1997年 | 105篇 |
1996年 | 87篇 |
1995年 | 67篇 |
1994年 | 54篇 |
1993年 | 50篇 |
1992年 | 23篇 |
1991年 | 20篇 |
1990年 | 13篇 |
1989年 | 11篇 |
1988年 | 10篇 |
1987年 | 8篇 |
1986年 | 4篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1983年 | 2篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 6篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1974年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有6463条查询结果,搜索用时 171 毫秒
601.
602.
气象灾害的研究和预防是野外职业安全卫生的一个重要领域 总被引:1,自引:0,他引:1
从事野外地质勘探的职工常常处于大自然环境中。自然环境灾害(气象灾害、地质灾害等)是造成地质勘探职业伤害的重要原因之一。在诸多的环境灾害中,又以气象灾害的危害最为突出。研究和预防气象灾害,是地质勘探安全卫生工作的重要内容。如果只研究人为职业伤害(一般工业安全卫生中的主要问题),而不研究环境灾害,特别是气象灾害所造成的事故和职业病,那是舍本求末。在地质勘探安全卫生领域中,研究气象灾害及其防护技术,既是保护野外作业职工安全和健康的需要,也是拓宽安全科学外延领域的有益探讨。 相似文献
603.
本文介绍了遥感技术在滑坡的现状调查和防治中的应用.提出了航天、航空遥感图像上滑坡现状、规模、易滑地点、稳定性评价等的直接和间接判读标志;并展望了遥感技术在滑坡动态监测中的应用前景. 相似文献
604.
605.
强化环境监测管理提高环境监测地位 总被引:3,自引:0,他引:3
段玉红 《中国环境管理干部学院学报》2004,14(4):33-35
总结和回顾了我国环境监测工作开展近三十年来所取得的非凡成绩,阐述了目前环境监测工作同整个环境保护事业相比较,同国外环境监测相比较存在的不足,并进一步提出了以"强化环境监测管理,提高环境监测地位"为核心的几点建议,旨在使我国的环境监测工作能更好地为环境保护和经济建设服务. 相似文献
606.
Vernal pools are vulnerable to loss through development and agricultural and forestry practices owing to their isolation from open water bodies and their small size. Some vernal pool-dependent species are already listed in New England as Endangered, Threatened, or Species of Special Concern. Vernal pool creation is becoming more common in compensatory mitigation as open water ponds, in general, may be easier to create than wooded wetlands. However, research on vernal pool creation is limited. A recent National Research Council study (2001) cites vernal pools as challenging to recreate. We reviewed documentation on 15 vernal pool creation projects in New England that were required by federal regulatory action. Our purpose was to determine whether vernal pool creation for compensatory mitigation in New England replaced key vernal pool functions by assessing project goals and documentation (including mitigation plans, pool design criteria, monitoring protocols, and performance standards). Our results indicate that creation attempts often fail to replicate lost pool functions. Pool design specifications are often based on conjecture rather than on reference wetlands or created pools that function successfully. Project monitoring lacks consistency and reliability, and record keeping by regulatory agencies is inadequate. Strengthening of protection of isolated wetlands in general, and standardization across all aspects of vernal pool creation, is needed to ensure success and to promote conservation of the long-term landscape functions of vernal pools. 相似文献
607.
Clow David W. Striegl Robert G. Nanus Leora Mast M. Alisa Campbell Donald H. Krabbenhoft David P. 《Water, Air, & Soil Pollution: Focus》2002,2(2):139-164
A chemical survey of 69 high-altitude lakes in seven national parks in the western United States was conducted during the fallof 1999; the lakes were previously sampled during the fall of 1985, as part of the Western Lake Survey. Lakes in parks in the Sierra/southern Cascades (Lassen Volcanic, Yosemite, Sequoia/Kings Canyon National Parks) and in the southern RockyMountains (Rocky Mountain National Park) were very dilute; medianspecific conductance ranged from 4.4 to 12.2 S cm-1 andmedian alkalinity concentrations ranged from 32.2 to 72.9 eqL-1. Specific conductances and alkalinity concentrations were substantially higher in lakes in the central and northernRocky Mountains parks (Grand Teton, Yellowstone, and GlacierNational Parks), probably due to the prevalence of more reactivebedrock types. Regional patterns in lake concentrations of NO3 and SO4 were similar to regional patterns in NO3 and SO4 concentrations in precipitation, suggestingthat the lakes are showing a response to atmospheric deposition.Concentrations of NO3 were particularly high in Rocky Mountain National Park, where some ecosystems appear to be undergoing nitrogen saturation. 相似文献
608.
The Information Cycle as a Framework for Defining Information Goals for Water-Quality Monitoring 总被引:2,自引:0,他引:2
/ The necessity to tailor information becomes increasingly urgent as the information revolution continues to generate ever-increasing flows of data and so-called information. From European experiences, a new approach for monitoring system design is suggested in this paper. In this approach, careful and detailed specification of information needs is a major contributing factor to the effectiveness of information products. To develop better specifications for information products, the process of collecting and transforming data into useful information requires careful thought and guidance. A dialogue between information users on one hand and information producers on the other is essential. This dialogue can be based on the information cycle, describing the continuous process from specifying information needs for water management and a strategy to collect information through data collection and data analysis up to utilization of information by water management. By following the respective steps in the information cycle, the process of information gathering can be completed. The cyclic character provides a quantitative means of connecting monitoring system design and operations with the information expectations and/or products required by management. 相似文献
609.
山东省水环境自动监测监控系统数据的应用设计和使用方法 总被引:1,自引:0,他引:1
山东省水环境自动监测监控子系统的主要功能是将全省水质自动站数据利用计算机网络、数据仓库等技术导入到环境监测数据仓库中,实现全省水环境自动监测的统一监控和监测信息的自动管理和发布。本文简单介绍了系统担制中心端监测数据统计应用部分的功能设计和实现方法。 相似文献
610.
国内外油田含油污泥处理技术 总被引:9,自引:1,他引:9
通过对国内外各种含油污泥处理工艺技术的调查分析和对比,提出了适合国内实际的含油污泥处理技术方案。以离心分离技术为核心,辅之以调质、倾析等多种预处理技术和高温裂解、生物处理等后续处理技术的污泥综合处理工艺,适于我国现阶段的含油污泥处理。 相似文献