首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   906篇
  免费   17篇
电工技术   8篇
化学工业   76篇
金属工艺   1篇
机械仪表   2篇
建筑科学   8篇
矿业工程   1篇
能源动力   4篇
轻工业   17篇
水利工程   8篇
无线电   13篇
一般工业技术   28篇
冶金工业   700篇
原子能技术   2篇
自动化技术   55篇
  2022年   7篇
  2021年   2篇
  2020年   4篇
  2019年   6篇
  2018年   9篇
  2017年   8篇
  2016年   8篇
  2015年   2篇
  2014年   10篇
  2013年   18篇
  2012年   12篇
  2011年   26篇
  2010年   17篇
  2009年   10篇
  2008年   12篇
  2007年   9篇
  2006年   7篇
  2005年   4篇
  2004年   8篇
  2003年   4篇
  2002年   5篇
  2001年   2篇
  2000年   5篇
  1999年   27篇
  1998年   205篇
  1997年   117篇
  1996年   88篇
  1995年   49篇
  1994年   30篇
  1993年   59篇
  1992年   16篇
  1991年   13篇
  1990年   9篇
  1989年   12篇
  1988年   7篇
  1987年   6篇
  1986年   5篇
  1985年   8篇
  1983年   1篇
  1982年   2篇
  1981年   5篇
  1980年   4篇
  1979年   1篇
  1978年   2篇
  1977年   19篇
  1976年   37篇
  1975年   1篇
  1974年   1篇
  1971年   1篇
  1955年   1篇
排序方式: 共有923条查询结果,搜索用时 15 毫秒
1.
A simple but comprehensive model considering homogeneous and micellar nucleation, coagulation, entry of radicals to particles and to micelles and radicals' exit from particles, is presented. The model is validated, in a starved semicontinuous heterophase polymerization of ethyl methacrylate, at three monomer addition rates. The model accurately describes the overall and instantaneous conversion, the average particle density and diameter, and the number and weight average molar masses evolutions over time. It is found that even though the average number of radicals is much smaller than 0.5, the system is not 0-1. An empirical function was used to describe the gel effect. The homogeneous nucleation was the prevailing mechanism for particle formation and large exit rates of radicals were observed. POLYM. ENG. SCI., 60: 223–232, 2019. © 2019 Society of Plastics Engineers  相似文献   
2.
A multi-level attention framework for tracking and segmentation of humans and objects under complex occlusions is investigated, featuring an effective probabilistic appearance-based technique for pixel reclassification during object grouping and splitting. A novel ’spatial-depth affinity metric’ is introduced in the conventional likelihood function, utilising information of both spatial locations of pixels and dynamic depth ordering of the component objects in grouping. Depth ordering estimation is achieved through a combination of top-down and bottom-up approach. Experiments on some realworld difficult scenarios of low quality and highly compressed videos demonstrate the very promising results achieved.  相似文献   
3.
4.
5.
The identification of adequate wastewater treatment for small communities is a complex problem since it demands a combination of data from different sources, such as aspects of the community and landscape, the receiving environment and the available wastewater treatment technologies. The Catalan Water Agency (Agència Catalana de l'Aigua) considered using an EDSS (Environmental Decision Support System) as a tool to help water managers select the most adequate treatment for the urban wastewater of nearly 3,500 small communities in Catalonia (Spain). From that moment, EDSS was applied to all the river basins in Catalonia. In this paper the authors present the results obtained for the 76 small communities located in one of these river basins: the Fluvia River Basin. The characteristics of the community used in the reasoning process of the EDSS, the list of selected wastewater treatment alternatives, the technical environmental justification for the selected treatments and the reasons for discarding, favouring or disadvantaging them are presented. Finally, some results for the Fluvia River Basin are compared with those obtained in other Catalan river basins with different characteristics in order to evaluate which are the significant features in identifying adequate wastewater treatments.  相似文献   
6.
7.
8.
9.
10.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号