全文获取类型
收费全文 | 2337篇 |
免费 | 129篇 |
国内免费 | 3篇 |
专业分类
电工技术 | 34篇 |
综合类 | 5篇 |
化学工业 | 658篇 |
金属工艺 | 63篇 |
机械仪表 | 39篇 |
建筑科学 | 198篇 |
矿业工程 | 4篇 |
能源动力 | 89篇 |
轻工业 | 196篇 |
水利工程 | 16篇 |
石油天然气 | 7篇 |
无线电 | 165篇 |
一般工业技术 | 453篇 |
冶金工业 | 110篇 |
原子能技术 | 12篇 |
自动化技术 | 420篇 |
出版年
2023年 | 28篇 |
2022年 | 54篇 |
2021年 | 79篇 |
2020年 | 50篇 |
2019年 | 71篇 |
2018年 | 54篇 |
2017年 | 58篇 |
2016年 | 86篇 |
2015年 | 88篇 |
2014年 | 107篇 |
2013年 | 164篇 |
2012年 | 140篇 |
2011年 | 200篇 |
2010年 | 104篇 |
2009年 | 133篇 |
2008年 | 147篇 |
2007年 | 135篇 |
2006年 | 107篇 |
2005年 | 87篇 |
2004年 | 84篇 |
2003年 | 54篇 |
2002年 | 63篇 |
2001年 | 33篇 |
2000年 | 36篇 |
1999年 | 30篇 |
1998年 | 26篇 |
1997年 | 28篇 |
1996年 | 28篇 |
1995年 | 22篇 |
1994年 | 17篇 |
1993年 | 16篇 |
1992年 | 16篇 |
1991年 | 10篇 |
1990年 | 9篇 |
1989年 | 17篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 9篇 |
1985年 | 8篇 |
1984年 | 8篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 3篇 |
1979年 | 3篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 4篇 |
1970年 | 4篇 |
1968年 | 2篇 |
1956年 | 2篇 |
排序方式: 共有2469条查询结果,搜索用时 0 毫秒
1.
Astrid Heidemann Lassen Frank Gertsen Jens Ove Riis 《Creativity & Innovation Management》2006,15(4):359-372
This paper explores the linkage between the entrepreneurial orientation of established firms and the development of radical innovation. Through five case studies in firms involved in radical innovation, three propositions are developed, suggesting that proactiveness, risk‐taking and autonomy stimulate the development of radical innovation, whereas competitive aggressiveness does not necessarily do so, as radical innovations are directed towards the creation of entirely new arenas of business, where existing competitors are not present. 相似文献
2.
3.
15年前柏林城市规划的定义与现在完全不同.至今,柏林的两个组成部分还有不同的规划理念:一方面,在西柏林.规划严格控制在划定的50平方公里两百万居民的边线范围内;另一方面,在前东德首都的东柏林.所有活动集中在有限的中心地区以展示其首都功能.而柏林周边地区没有包含在任何区域规划系统内.这样的结果导致东、西柏林以及柏林同周边乡镇有完全不同的生活方式. 相似文献
4.
Jens‐Peter Heinß Dr. 《真空研究与实践》2007,19(5):20-23
Hydrogen free amorphous carbon coatings ‐ deposited with plasma‐activated high‐rate evaporation By using the technology of the plasmaactivated electron beam evaporation we deposited hydrogen free amorphous carbon coatings with deposition rates of up to 100 μm/h. The results of the mechanical and tribological investigations show the potential of these layers for the use in case of wear resistance. Hardnesses of up to 16GPa were proved. The actual state of the characterisation of the coatings is described and the outlook onto possibilities of further optimisation is given. 相似文献
5.
Tresadern P.A. Thies S.B. Kenney L.P.J. Howard D. Goulermas J.Y. 《Pervasive Computing, IEEE》2008,7(2):62-69
The clinical set-up tool integrates fast parameter selection and a user-friendly interface to help electrical muscle stimulators more efficiently treat patients with neurological injuries. A key challenge in increasing functional electrical stimulation systems' clinical acceptance is facilitating or automating parameter selection, optimization, and programming to make the underlying engineering transparent to the user. To this end, we present the clinical set-up tool (CST), a finite-state-machine-based controller that integrates accurate, automatic parameter optimization in an intuitive user interface. Unlike other approaches, we employ a numerical algorithm that uses real-life data and well-defined criteria to rapidly optimize parameter values. 相似文献
6.
W. Thies 《European Journal of Lipid Science and Technology》1995,97(11):411-413
Oleic acid (18:1 n9), vaccenic acid (18:1 n7). and petroselinic acid (18:1 n12) can not be separated by gas chromatography (GLC) as their methylesters. But separations of their n-butyl esters are feasible. With 0.1 mol Na-tert-butanol as catalyst, dissolved in n-butanol, an extraction from the seed grist and simultaneous transbutylation of the lipids can be achieved within 20 min at room temperature. Using a capillary column (60 m DB-23, 0.25 μ, J&W, No. 122-2362), hydrogen as carrier gas and an oven temperature of 220° C, one analysis can be performed within 13 min. 相似文献
7.
Although the banking industry plays a central role in the world economy and has traditionally been an innovative user of information technology, banks are struggling to develop mature Internet strategies. A model used to analyze the type of Internet activities among a sample of banks as well as their level of sophistication and customization is useful not only for revealing unexploited opportunities in the banking sector but also for guiding the strategy-building process of organizations in other industries. 相似文献
8.
Asendorpf Jens B.; Warkentin Veronique; Baudonnière Pierre-Marie 《Canadian Metallurgical Quarterly》1996,32(2):313
Eighteen-month-old children were tested for mirror self-recognition using the classic rouge test or an alternative procedure, for social contingency awareness by being closely imitated for a long time, and for the capacity for communication by synchronic imitation. The classic mirror rouge test was shown to produce false negatives. Most recognizers and nonrecognizers became aware of being imitated and imitated the activity of a model, but only recognizers engaged in sustained synchronic imitation of the model. The results support our hypothesis that self-recognition and spontaneous perspective-taking develop in close synchrony because both require a capacity for secondary representation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
W. Thies 《European Journal of Lipid Science and Technology》1993,95(1):20-23
With dimethyldisulfide the methylthio-derivatives of unsaturated fatty acid methylesters are readily formed within 30 min at 70°C. Whereas the analysis of oleic and petroselinic acid methyl esters by gas liquid chromatography is very time consuming (separation time: 1 hour), their corresponding methylthio-derivatives can be quantitatively determinated within 14 min. 相似文献
10.