全文获取类型
收费全文 | 1301篇 |
免费 | 67篇 |
国内免费 | 4篇 |
专业分类
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 |
出版年
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.
97.
Chiuhsiang Joe Lin 《Journal of Nuclear Science and Technology》2016,53(1):102-111
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.
Joe Liscouski 《Journal of Automated Methods and Management in Chemistry》1997,19(6):199-204
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.
Marcus A. Worsley Peter J. Pauzauskie Sergei O. Kucheyev Joseph M. Zaug Alex V. Hamza Joe H. Satcher Theodore F. Baumann 《Acta Materialia》2009,57(17):5131-5136
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