全文获取类型
收费全文 | 1273篇 |
免费 | 37篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 12篇 |
综合类 | 1篇 |
化学工业 | 303篇 |
金属工艺 | 32篇 |
机械仪表 | 44篇 |
建筑科学 | 24篇 |
能源动力 | 62篇 |
轻工业 | 52篇 |
水利工程 | 6篇 |
石油天然气 | 4篇 |
无线电 | 170篇 |
一般工业技术 | 297篇 |
冶金工业 | 114篇 |
原子能技术 | 11篇 |
自动化技术 | 179篇 |
出版年
2023年 | 13篇 |
2022年 | 21篇 |
2021年 | 47篇 |
2020年 | 40篇 |
2019年 | 31篇 |
2018年 | 51篇 |
2017年 | 39篇 |
2016年 | 44篇 |
2015年 | 25篇 |
2014年 | 37篇 |
2013年 | 89篇 |
2012年 | 52篇 |
2011年 | 59篇 |
2010年 | 55篇 |
2009年 | 56篇 |
2008年 | 54篇 |
2007年 | 55篇 |
2006年 | 41篇 |
2005年 | 40篇 |
2004年 | 29篇 |
2003年 | 29篇 |
2002年 | 22篇 |
2001年 | 19篇 |
2000年 | 15篇 |
1999年 | 17篇 |
1998年 | 32篇 |
1997年 | 26篇 |
1996年 | 30篇 |
1995年 | 18篇 |
1994年 | 29篇 |
1993年 | 42篇 |
1992年 | 12篇 |
1991年 | 21篇 |
1990年 | 11篇 |
1989年 | 17篇 |
1988年 | 4篇 |
1987年 | 13篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1982年 | 9篇 |
1981年 | 5篇 |
1980年 | 7篇 |
1979年 | 4篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1973年 | 5篇 |
排序方式: 共有1311条查询结果,搜索用时 15 毫秒
1.
Kumar S. Ganesh Sridhar S. S. Hussain Azham Manikanthan S. V. Padmapriya T. 《Multimedia Tools and Applications》2022,81(7):9091-9109
Multimedia Tools and Applications - Discovering the relevant web services for specific applications in the dynamically changing business world becomes very critical. Researchers have used many... 相似文献
2.
Wireless Personal Communications - In this paper, cooperative communication (CC) assisted cognitive wireless sensor network (CWSN) is presented for monitoring health and activity of an end-user in... 相似文献
3.
4.
Energy transfer from photo-excited electrons in a metal thin film to the dielectric substrate is important for understanding the ultrafast heat transfer process across the two materials. Substantial research has been conducted to investigate heat transfer in a metal-dielectric structure. In this work, a two-temperature model in metal was used to analyze the interface electron and dielectric substrate coupling. An improved temperature and wavelength-dependent Drude–Lorentz model was implemented to interpret the signals obtained in optical measurements. Ultrafast pump-and-probe measurements on Au-Si samples were carried out, where the probe photon energy was chosen to be close to the interband transition threshold of gold to minimize the influence of non-equilibrium electrons on the optical response and maximize the thermal modulation to the optical reflectance. Electron-substrate interface thermal conductance at different pump laser fluences was obtained, and was found to increase with the interface temperature. 相似文献
5.
A Synthetic Transcriptional Activator of Genes Associated with the Retina in Human Dermal Fibroblasts
下载免费PDF全文
![点击此处可从《Chembiochem : a European journal of chemical biology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
6.
Agrawal Prachi Ganesh Talari Mohamed Ali Wagdy 《Neural computing & applications》2021,33(11):5989-6008
Neural Computing and Applications - To obtain the optimal set of features in feature selection problems is the most challenging and prominent problem in machine learning. Very few human-related... 相似文献
7.
8.
9.
R. V. Iyer K. Sooryanarayana T. N. Guru Row K. Vijayan 《Journal of Materials Science》2003,38(1):133-139
Using X-ray diffraction data, the behaviour of Kevlar 49 fibres at low temperatures, up to –100°C, has been analysed. During cooling, the basal plane of the monoclinic unit cell shrinks whereas the c- (unique, chain axis) length is not significantly affected. In contrast, in the return heating cycle to ambient temperature, the basal plane expands and contraction occurs along the chain direction. The unit cell registers a reduction in volume in both the cooling and heating cycles. Conspicuously, after a cycle of cooling and heating, the unit cell does not return to its initial volume. 相似文献
10.
A key performance parameter of a manufacturing network or supply chain is its cycle time; the time that a typical item spends in the network. A previous simulation study on a semiconductor assembly and test facility showed that cycle times could be reduced by having smooth input and service rates. This suggested that there is a “cycle time principle” that, for a system with a specified throughput or input rate, the shortest cycle times are obtained when the input and service rates do not vary over time. We prove that this principle is true for the M/G/1 and M/M/s queueing systems and Jackson networks. The analysis involves establishing several results on the concavity of waiting time probabilities and the convexity of expected waiting times and queue lengths, as functions of input and service rates. These results also have natural uses in other optimization problems. 相似文献