全文获取类型
收费全文 | 245篇 |
免费 | 14篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 52篇 |
废物处理 | 4篇 |
环保管理 | 33篇 |
综合类 | 122篇 |
基础理论 | 25篇 |
污染及防治 | 6篇 |
评价与监测 | 17篇 |
社会与环境 | 6篇 |
灾害及防治 | 21篇 |
出版年
2024年 | 2篇 |
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 6篇 |
2020年 | 2篇 |
2019年 | 8篇 |
2018年 | 3篇 |
2017年 | 2篇 |
2016年 | 8篇 |
2015年 | 4篇 |
2014年 | 9篇 |
2013年 | 11篇 |
2012年 | 11篇 |
2011年 | 21篇 |
2010年 | 16篇 |
2009年 | 10篇 |
2008年 | 16篇 |
2007年 | 21篇 |
2006年 | 17篇 |
2005年 | 13篇 |
2004年 | 13篇 |
2003年 | 17篇 |
2002年 | 14篇 |
2001年 | 9篇 |
2000年 | 15篇 |
1999年 | 6篇 |
1998年 | 4篇 |
1997年 | 3篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1989年 | 3篇 |
1988年 | 3篇 |
排序方式: 共有286条查询结果,搜索用时 781 毫秒
61.
自2016年以来,防灾科技学院对1920年海原特大地震形成的黄土地震滑坡开展了全面系统的野外调查工作,获取了数百个黄土地震滑坡的详细调查资料,为便于资料的管理和应用,建立了首个海原特大地震黄土地震滑坡数据库系统.主要从资料来源、access 2019软件系统的可行性、数据库的设计及建设4个方面详细介绍了海原特大地震黄土... 相似文献
62.
昆明市环境监测信息系统的开发与完善 总被引:1,自引:0,他引:1
通过环境监测信息控制系统管理环境监测数据,可提高数据管理水平和数据处理质量、速度,可将环境监测信息尽快地转化为决策依据,有利于提高环境管理和环境污染治理决策水平.本文总结了昆明市环境监测信息系统的设计、开发要点并提出了进一步完善的展望. 相似文献
63.
上海市在用车监测与维修制度探讨 总被引:1,自引:0,他引:1
根据上海市机动车辆的管理现状,提出上海市在用车I/M制度体系网络、监测方法、数据收集网络与“通过/不通过”排放限值方面的基本设想,为建立一个真正有效的在用车监测与维修制度提供依据。 相似文献
64.
65.
论述了塑料模具标准件、通用件制造工艺数据库的开发过程。利用C++编程实现对数据库的检索、管理及用户界面设计,利用SQLServer建立工艺数据库,运用API编程技术完成工序图生成和编辑,采用ADO技术对数据库进行访问,以及系统的功能。 相似文献
66.
67.
68.
69.
70.
V. Krivtsov R. Watling S. J. J. Walker D. Knott J. W. Palfreyman H. J. Staines 《Ecological modelling》2003,170(2-3):393
Since 1994 data on fungal fruiting have been gathered in the Dawyck Botanic Garden outside Edinburgh, including that for eight plots within a 7.5 ha wood, which has been left unmanaged in order to investigate relationships amongst fungal succession, habitat characteristics and local weather patterns. The climatic data are provided by a small meteorological station situated on site. To handle nearly 4000 entries of data so far collected a computer database was constructed. This assists querying of the information so that changes in fungal communities and patterns of succession can be observed, and the relevant data extracted for further analysis. To aid in this analysis, and to give the user full control over editing, updating and querying the database, a special computer program was compiled.Analysis of the database records revealed that the currently known Dawyck fungal community comprises over 620 different taxa, and the species list increases every year. Although some species of mycorrhizal fungi showed high specificity towards their preferred host either at species (e.g. Lactarius blennius with beech, Lactarius quietus with oak, Russula fellea and Russula mairei with beech), or at genus level (e.g. Suillus spp. with Pinaceae), some other common fungi (e.g. of the genus Amanita) were found to have very wide host ranges. In addition, unusual mycorrhizal associations have also been recorded. A lime tree (Tilia), which is supposedly primarily endomycorrhizal, has been found regularly associated with Russula cyanoxantha, Russula parazurea, Russula pectinata and Inocybe fastigiata. Many common Scottish fungi were found to be associated with introduced exotic trees, which is illustrated on the example of Pseudotsuga menziesii (Douglas Fir).The software created utilises the Microsoft Office suite of programs. Microsoft Access was used to construct the database, and Microsoft Excel was used for statistical investigations. The software was programmed using Microsoft Visual Basic, and provided a means of extracting the necessary data stored in Access and controlling the formulae used in Excel for their analysis. The recorded seasonal patterns of fungal fruiting was successfully described by a simulation mathematical model comprising differential and algebraic equations. This model may now be used as a submodel within more complex models describing terrestrial ecosystem processes. Examples of model simulations and sensitivity analysis are given and implications for future research discussed. 相似文献