全文获取类型
收费全文 | 1790篇 |
免费 | 87篇 |
国内免费 | 9篇 |
专业分类
电工技术 | 23篇 |
综合类 | 7篇 |
化学工业 | 565篇 |
金属工艺 | 39篇 |
机械仪表 | 36篇 |
建筑科学 | 127篇 |
矿业工程 | 6篇 |
能源动力 | 41篇 |
轻工业 | 106篇 |
水利工程 | 12篇 |
石油天然气 | 1篇 |
无线电 | 125篇 |
一般工业技术 | 318篇 |
冶金工业 | 238篇 |
原子能技术 | 4篇 |
自动化技术 | 238篇 |
出版年
2023年 | 32篇 |
2022年 | 34篇 |
2021年 | 60篇 |
2020年 | 39篇 |
2019年 | 34篇 |
2018年 | 43篇 |
2017年 | 32篇 |
2016年 | 67篇 |
2015年 | 48篇 |
2014年 | 67篇 |
2013年 | 103篇 |
2012年 | 94篇 |
2011年 | 116篇 |
2010年 | 71篇 |
2009年 | 75篇 |
2008年 | 88篇 |
2007年 | 82篇 |
2006年 | 68篇 |
2005年 | 59篇 |
2004年 | 46篇 |
2003年 | 42篇 |
2002年 | 47篇 |
2001年 | 24篇 |
2000年 | 37篇 |
1999年 | 33篇 |
1998年 | 47篇 |
1997年 | 44篇 |
1996年 | 26篇 |
1995年 | 24篇 |
1994年 | 26篇 |
1993年 | 22篇 |
1992年 | 14篇 |
1991年 | 20篇 |
1990年 | 15篇 |
1989年 | 11篇 |
1988年 | 8篇 |
1987年 | 9篇 |
1986年 | 9篇 |
1985年 | 17篇 |
1984年 | 19篇 |
1983年 | 17篇 |
1982年 | 11篇 |
1981年 | 11篇 |
1980年 | 8篇 |
1979年 | 15篇 |
1976年 | 13篇 |
1975年 | 6篇 |
1974年 | 12篇 |
1973年 | 6篇 |
1969年 | 6篇 |
排序方式: 共有1886条查询结果,搜索用时 0 毫秒
21.
The results of an experimental study of electro-optic modulators and waveguides based on polymeric materials are presented. Included are the design, fabrication, and testing of integrated Mach-Zehnder modulators, which are based on polymer films that contain a novel, nonlinear electro-optic chromophore. Studies also show the efficacy of photolithography or photobleaching by the use of this chromophore to form passive, branching waveguides, which are operated at the 1300-nm wavelength. 相似文献
22.
Yannick Schellander Marius Winter Maurice Schamber Fabian Munkes Patrick Schalberger Harald Kuebler Tilman Pfau Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(5):363-372
In this work, real-time ultraviolet photodetectors are realized through metal–semiconductor–metal (MSM) structures. Amorphous indium gallium zinc oxide (a-IGZO) is used as semiconductor material and gold as metal electrodes. The readout of an individual sensor is implemented by a transimpedance amplifier (TIA) consisting of an all-enhancement a-IGZO thin-film transistor (TFT) operational amplifier and a switched capacitor (SC) as feedback resistance. The photosensor and the transimpedance amplifier are both manufactured on glass substrates. The measured photosensor possesses a high responsivity R , a low response time t R E S , and a good noise equivalent power value NEP . 相似文献
23.
Sheikh Abdullah Al Nusayer Patrick Schalberger Holger Baur Florian Kleber Norbert Fruehauf 《Journal of the Society for Information Display》2023,31(9):535-547
Active matrix prestressed microelectromechanical shutter displays enable outstanding optical properties as well as robust operating performance. The microelectromechanical systems (MEMS) shutter elements have been optimized for higher light outcoupling efficiency with lower operation voltage and higher pixel density. The MEMS elements have been co-fabricated with self-aligned metal-oxide thin-film transistors (TFTs). Several optimizations were required to integrate MEMS process without hampering the performance of both elements. The optimized display process requires only seven photolithographic masks with ensuring proper compatibility between MEMS shutter and metal-oxide TFT process. 相似文献
24.
Masoud Mohazzab Norbert Mulders Melora Larson Al Nash 《Journal of Low Temperature Physics》1998,113(5-6):1031-1036
In this paper we discuss a pulsed second sound experiment, aimed at determining accurately the critical exponent , and the predicted logarithmic correction to scaling, for the superfluid density along a tricritical path in the
3
He-
4
He phase diagram. We present an accurate estimate for the limits for closest approach to the tricritical point, as set by gravitationally induced sample inhomogeneities and finite size effects, and discuss some of the complications associated with measurements close to the tricritical point. 相似文献
25.
Norbert Wilke 《Magma (New York, N.Y.)》1998,6(2-3):147-147
26.
On-column solvent exchange, using many of the principles of solid-phase extraction, has been implemented to significantly reduce evaporation cycle time following reverse-phase preparative HPLC. Additional benefits, such as a reduced potential for salt formation, thermal decomposition, and residual solvent, are also described. Fractions obtained from preparative separations, typically in a large volume of acetonitrile:water, are injected into the preparative HPLC and then eluted in acetonitrile, creating a new fraction in a volatile organic solvent. Minimal modification to the instrument was required, and unattended operation is possible. Acetonitrile evaporation is achieved within 3 h, compared with 17 h for aqueous-based fractions; lower temperatures can be used during the evaporation step; mobile-phase additives, likely to form salts with the target compound if concentrated in the fraction, are removed before evaporation; sample recovery and purity are unaffected. 相似文献
27.
Patrick Schalberger Marcus Herrmann Steffen Hoehla Norbert Fruehauf 《Journal of the Society for Information Display》2011,19(7):496-502
Abstract— In the past, a five‐mask LTPS CMOS process requiring only one single ion‐doping step was used. Based on that process, all necessary components for the realization of a fully integrated AMOLED display using a 3T1C current‐feedback pixel circuit has recently been developed. The integrated data driver is based on a newly developed LTPS operational amplifier, which does not require any compensation for Vth or mobility variations. Only one operational amplifier per column is used to perform digital‐to‐analog conversion as well as current control. In order to achieve high‐precision analog behavior, the operational amplifier is embedded in a switched capacitor network. In addition to circuit verification by simulation and analytic analysis, a 1‐in. fully integrated AMOLED demonstrator was successfully built. To the best of the authors' knowledge, this is the first implementation of a fully integrated AMOLED display with current feedback. 相似文献
28.
Christiane Jasmin Reinert‐Weiss Holger Baur Sheikh Abdullah Al Nusayer David Duhme Norbert Frühauf 《Journal of the Society for Information Display》2017,25(2):90-97
Conventional adaptive driving beam headlamps are limited in achieving still higher quantities of switchable pixels by the number of LEDs and movable elements needed. In this paper, it is shown that by integrating an active matrix liquid crystal display module, it is possible to realize fully adaptive high‐resolution headlights without mechanical elements and a finite number of LED with 30 k switchable pixels. 相似文献
29.
30.
The paper describes the new development programme of the Polish information infrastructure. The programme, called in Polish PIONIER: (English—PIONEER) Polish Optical Internet, Advanced Applications, Services and Technologies for the Information Society, has been proposed to the Polish State Committee for Scientific Research and has been accepted. The aim of the programme is to create an advanced infrastructure together with tools, services and applications available to the entire scientific community and eventually to government and local administrations as well as society in general. Services and applications are expected to appear as selected pilot realizations in order to verify deployed technologies. Some of the pilot realizations and testbeds are also presented in the paper. 相似文献