全文获取类型
收费全文 | 3781篇 |
免费 | 202篇 |
国内免费 | 87篇 |
专业分类
电工技术 | 257篇 |
技术理论 | 1篇 |
综合类 | 677篇 |
化学工业 | 115篇 |
金属工艺 | 11篇 |
机械仪表 | 35篇 |
建筑科学 | 1764篇 |
矿业工程 | 74篇 |
能源动力 | 146篇 |
轻工业 | 72篇 |
水利工程 | 412篇 |
石油天然气 | 10篇 |
武器工业 | 1篇 |
无线电 | 133篇 |
一般工业技术 | 148篇 |
冶金工业 | 84篇 |
原子能技术 | 1篇 |
自动化技术 | 129篇 |
出版年
2024年 | 24篇 |
2023年 | 56篇 |
2022年 | 134篇 |
2021年 | 129篇 |
2020年 | 121篇 |
2019年 | 84篇 |
2018年 | 60篇 |
2017年 | 88篇 |
2016年 | 108篇 |
2015年 | 176篇 |
2014年 | 441篇 |
2013年 | 224篇 |
2012年 | 324篇 |
2011年 | 376篇 |
2010年 | 319篇 |
2009年 | 239篇 |
2008年 | 231篇 |
2007年 | 249篇 |
2006年 | 215篇 |
2005年 | 121篇 |
2004年 | 83篇 |
2003年 | 63篇 |
2002年 | 46篇 |
2001年 | 30篇 |
2000年 | 36篇 |
1999年 | 19篇 |
1998年 | 13篇 |
1997年 | 8篇 |
1996年 | 3篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 2篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 5篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1984年 | 5篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1974年 | 1篇 |
1969年 | 1篇 |
1966年 | 1篇 |
1961年 | 1篇 |
1955年 | 2篇 |
排序方式: 共有4070条查询结果,搜索用时 15 毫秒
81.
82.
骆红旭 《中国水能及电气化》2011,(4)
农村水电点多面广,老化严重,金华市积极构建、完善监管体系,创新水电站规范化建设、信息化网格化管理、安全年检等监管平台,提升了监管水平.金华市水电管理工作紧紧围绕公共安全管理、以"平安金华水电"建设为出发点和落脚点,全面贯彻落实科学发展观,保障水电安全. 相似文献
83.
为了揭示城市热岛形成机制,基于MODIS资料,结合自动气象站实测的气象资料,利用地表能量参数化方法估算了地表热通量,分析了城乡地表热通量的空间分布及变化特征.结果表明城乡地气热交换差异明显,与相关文献对比证明该方法是可行、有效的. 相似文献
84.
Philip Gyau-Boakye 《国际水》2013,38(3):189-195
Abstract Water is vital for the survival and development of every community or society. The health of a given community is reflected to a large extent in the water quality of the community's available water resources. In Ghana, efforts have been made since colonial days to supply both the urban and the rural communities with potable water to enhance the rapid socio-economic development of the country. It is economically viable due to the remoteness of most of the rural communities to supply them with potable water from local sources such as groundwater. The urban water supply systems are mainly based on surface water sources. With the ever-expanding population, there is a need to improve freshwater resources conservation and management in order to avoid impending shortages. To ensure the total coverage of all rural and urban communities by the year 2020, a huge capital outlay of $1 billion and 51.5 billion, respectively, is needed. Most of these funds are expected to come from the private sector, both local and foreign, with the Government making some substantial contribution. 相似文献
85.
Shue Tuck Wong 《国际水》2013,38(4):586-594
Abstract This study seeks to examine source choice perception and sustainable rural water supply development in Ban Thadindam, a Thai village situated about 220 km north of Bangkok. It makes use of an elementary schematic matrix that was initially developed for the valuation of water sources as perceived by water users in East Africa. In applying the elementary choice scheme, the author interviewed the village Kamnan (district officer) and a few villagers. The results of this study show that a wide range of water supply sources was perceived by the Kamnan. Out of a practical range of six sources, four were perceived and accepted, roof (rain water), river, spring, and pond; and two were perceived but not accepted: well and canal. The reason why well and canal water sources were rejected was because of their hardness and turbidity. Of the four sources accepted, roof (rain water) was rated very favorably as the preferred choice while river, spring, and pond sources were judged equally favorable. Awareness of source choice and the conditions under which choice is made is crucial for the understanding and development of sustainable rural water supply. By adopting a wide combination of sources and integrating them to provide a rich water supply for treatment, and by taking advantage of filtration technology given by the Asian Institute of Technology, Environmental Engineering Division, the villagers, with the help of the Project Managing Committee, transformed the demonstration filtration facility into a sustainable rural water supply system. The latter succeeded not only in providing adequate filtered water for the majority of the households in Ban Thadindam but also in satisfying the water requirements for the whole village for two decades. The success of the rural water supply system has been attributable to many factors, but most important was the awareness the villagers have in the understanding of the interrelations between landscape, range of choice and the interaction between community participation, technology, and environment. 相似文献
86.
Much effort has gone into the recognition of the human right to water. Without doubt, this milestone influences governance and decision making processes at many scales so it is essential now to shift the discussion from the legal and conceptual framework to practice. Along this line, the article proposes a methodology for monitoring access to water in rural areas using the framework of this human right. The practicality of the approach is demonstrated by a case study carried out in Nicaragua. Different criteria of the right to water were included in surveys and structured interviews that were conducted in rural households and water committees, respectively. A discussion analyzes the advantages and challenges of using this framework. Finally, the approach provides elements for policy making that can be used by different stakeholders in the development and human rights sectors. 相似文献
87.
文章针对目前中等高等师范教育研究缺乏对地方应用型本科院校师范教育服务农村基础教育的探索与实践的问题,调查分析了辽东地区农村小学教师的现状,以辽东学院小学教育专业改革实践为依托,依据基础教育新课程改革以及地方社会经济发展对小学教师素质的要求,构建了地方高师院校小学教育专业服务农村基础教育的人才综合培养模式,指出地方高师院校小学教育专业人才培养要以教师职业信念教育为先导,奠定人才培养的思想性;以课程体系构建为核心,突出人才培养的综合性;以实践教学环节为途径,实现人才培养的应用性;以教学方法和手段的改革为措施,促进教育科研能力的提升。实践证明,这种人才培养模式有效地提高了人才质量,毕业生均以良好的教师素养和职业能力受到用人单位欢迎。 相似文献
88.
依据2011年中央1号文件关于建立水利工程投入稳定增长机制的政策措施,结合静宁县农村供水工程投资实际,探究建立公共财政投资和金融投资建设供水主体工程,群众投资投劳建设供水入户工程,社会资金投入提高供水入户标准的农村供水工程投入稳定增长机制,为工程实施提供资金保障. 相似文献
89.
农村饮水安全工程供水效益差,运行管理难以维持,而工程能够长效运行的前提是收入大于正常运行成本。在对影响农村饮水安全工程收入和运行成本相关因素的变化进行分析的基础上,模拟9个情景,运用盈亏平衡分析法对调查数据进行经济评价,得出影响农村饮水安全工程运行经济效果的主要问题,提出提高农村饮水安全工程运行效率的对策和建议。 相似文献
90.
通过对数据采集、数据利用、数据分析、数据跟踪等4个步骤的理论阐述、内容规划和关键技术研究,提出了以数据为核心进行农村水电综合管理信息系统建设的理论并结合广西地方水电信息管理系统的实际建设情况对其进行了实践验证,为农村水电站信息化建设探索了一条技术含量高、可持续发展、经济实用的新模式。 相似文献