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   1301篇
  免费   67篇
  国内免费   4篇
电工技术   22篇
综合类   1篇
化学工业   216篇
金属工艺   46篇
机械仪表   26篇
建筑科学   73篇
矿业工程   11篇
能源动力   45篇
轻工业   137篇
水利工程   8篇
石油天然气   12篇
无线电   150篇
一般工业技术   192篇
冶金工业   167篇
原子能技术   20篇
自动化技术   246篇
  2023年   16篇
  2022年   15篇
  2021年   20篇
  2020年   17篇
  2019年   23篇
  2018年   26篇
  2017年   33篇
  2016年   37篇
  2015年   30篇
  2014年   35篇
  2013年   97篇
  2012年   55篇
  2011年   83篇
  2010年   48篇
  2009年   69篇
  2008年   77篇
  2007年   57篇
  2006年   65篇
  2005年   52篇
  2004年   37篇
  2003年   30篇
  2002年   30篇
  2001年   27篇
  2000年   22篇
  1999年   24篇
  1998年   34篇
  1997年   26篇
  1996年   11篇
  1995年   19篇
  1994年   14篇
  1993年   24篇
  1992年   13篇
  1991年   8篇
  1990年   12篇
  1989年   14篇
  1988年   10篇
  1987年   11篇
  1986年   6篇
  1985年   10篇
  1984年   13篇
  1983年   11篇
  1982年   14篇
  1981年   12篇
  1980年   8篇
  1979年   14篇
  1976年   9篇
  1975年   9篇
  1974年   8篇
  1973年   6篇
  1970年   3篇
排序方式: 共有1372条查询结果,搜索用时 94 毫秒
91.
92.
93.
94.
With the increased cost of energy, use of energy in cement plants must be reduced. Various means of reducing energy use in existing plants by changes in plant practices are suggested, with estimates of the magnitude of the major reductions.  相似文献   
95.
96.
Q£A Hellovon     
我们采访了伦敦插画家Von,去了解他结合了细节图与数码元素的独特风格。  相似文献   
97.
Task analysis methods provide an insight for quantitative and qualitative predictions of how people will use a proposed system, though the different versions have different emphases. Most of the methods can attest to the coverage of the functionality of a system and all provide estimates of task performance time. However, most of the tasks that operators deal with in a digital work environment in the main control room of an advanced nuclear power plant require high mental activity. Such mental tasks overlap and must be dealt with at the same time; most of them can be assumed to be highly parallel in nature. Therefore, the primary aim to be addressed in this paper was to develop a method that adopts CPM-GOMS (cognitive perceptual motor-goals operators methods selection rules) as the basic pattern of mental task analysis for the advanced main control room. A within-subjects experiment design was used to examine the validity of the modified CPM-GOMS. Thirty participants participated in two task types, which included high- and low-compatibility types. The results indicated that the performance was significantly higher on the high-compatibility task type than on the low-compatibility task type; that is, the modified CPM-GOMS could distinguish the difference between high- and low-compatibility mental tasks.  相似文献   
98.
This paper provides some initial considerations into the design and function of the Data Librarian. The first part (Liscouski, J., 1997, Journal of Automatic Chemistry, 19, 193-197) described the need for the Librarian.  相似文献   
99.
The importance of intensive study of the individual subject in counseling research and the importance of the development of appropriate designs and analytical procedures for single-subject research has been recognized. Single-subject experiments are not always possible or ethical, but when they can be performed, treatment times should be randomly assigned to treatments, as this randomization is essential to provide the basis for a statistical test. The assumption of random sampling is not met in single-subject experiments. However, the data from a randomized single-subject experiment can be analyzed by use of a randomization test because such tests do not require random sampling. Randomized single-subject experiments can be helpful in determining what is best for a particular client, and systematic replications of such experiments can help in generalizing to other subjects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
Here, we present the synthesis and characterization of low-density single-walled carbon nanotube-based aerogels (SWNT-CA). Aerogels with varying nanotube loading (0–55 wt.%) and density (20–350 mg cm?3) were fabricated and characterized by four-probe method, electron microscopy, Raman spectroscopy and nitrogen porosimetry. Several properties of the SWNT-CAs were highly dependent upon nanotube loading. At nanotube loadings of 55 wt.%, shrinkage of the aerogel monoliths during carbonization and drying was almost completely eliminated. Electrical conductivities are improved by an order of magnitude for the SWNT-CA (55 wt.% nanotubes) compared to those of foams without nanotubes. Surface areas as high as 184 m2 g?1 were achieved for SWNT-CAs with greater than 20 wt.% nanotube loading.  相似文献   
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