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   61篇
  免费   1篇
电工技术   2篇
化学工业   30篇
机械仪表   1篇
建筑科学   2篇
能源动力   2篇
轻工业   3篇
无线电   5篇
一般工业技术   3篇
冶金工业   1篇
自动化技术   13篇
  2023年   1篇
  2022年   2篇
  2021年   1篇
  2020年   1篇
  2017年   1篇
  2016年   1篇
  2015年   1篇
  2014年   2篇
  2013年   8篇
  2011年   3篇
  2010年   4篇
  2009年   3篇
  2008年   6篇
  2007年   5篇
  2004年   1篇
  2003年   3篇
  2002年   3篇
  1997年   1篇
  1996年   4篇
  1993年   1篇
  1992年   1篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   2篇
  1982年   1篇
  1977年   1篇
排序方式: 共有62条查询结果,搜索用时 0 毫秒
1.
2.
Two-Photon Lithography, thanks to its very high sub-diffraction resolution, has become the lithographic technique par excellence in applications requiring small feature sizes and complex 3D pattering. Despite this, the fabrication times required for extended structures remain much longer than those of other competing techniques (UV mask lithography, nanoimprinting, etc.). Its low throughput prevents its wide adoption in industrial applications. To increase it, over the years different solutions have been proposed, although their usage is difficult to generalize and may be limited depending on the specific application. A promising strategy to further increase the throughput of Two-Photon Lithography, opening a concrete window for its adoption in industry, lies in its combination with holography approaches: in this way it is possible to generate dozens of foci from a single laser beam, thus parallelizing the fabrication of periodic structures, or to engineer the intensity distribution on the writing plane in a complex way, obtaining 3D microstructures with a single exposure. Here, the fundamental concepts behind high-speed Two-Photon Lithography and its combination with holography are discussed, and the literary production of recent years that exploits such techniques is reviewed, and contextualized according to the topic covered.  相似文献   
3.
Patients with advanced thyroid cancer harboring NTRK rearrangements can be treated with highly effective selective inhibitors. Immunohistochemistry (IHC) analysis, to detect Trk protein expression, represents an appealing screening strategy for NTRK rearrangements, but its efficacy has been poorly explored in thyroid cancer. The aim of this study is to investigate the diagnostic utility of Trk IHC in the identification of NTRK rearrangements. A series of 26 follicular-derived thyroid tumors, positive for NTRK rearrangements, and 28 NTRK fusion-negative controls were retrospectively analyzed by IHC using the pan-Trk monoclonal antibody (clone EPR17341) on the Ventana system. Area under the curve (AUC), sensitivity and specificity were calculated by ROC analysis. Trk expression was detected in 25 samples, including 22 out of the 26 NTRK-rearranged (84.6%) and three out of 28 NTRK-negative samples (10.7%). Four out of twenty-six NTRK-rearranged thyroid tumors were negative for Trk expression (15.4%), all carrying the ETV6/NTRK3 fusion. The AUC, sensitivity and specificity were 0.87, 0.85 and 0.89, respectively. A screening based on IHC analysis showed limited sensitivity and specificity in the identification of NTRK-rearranged tumors. Since falsely negative results could preclude the administration of effective targeted drugs, alternative detection strategies should be considered for thyroid cancer.  相似文献   
4.
5.
A multicentre evaluation of the Monarch centrifugal analyser is reported. Precision, linearity and accuracy were assessed by comparison with routine methods. Calibration stability, photometric and dispensing accuracy, and carry-over related to samples and reagents were also evaluated. The overall performance of the instrument was good, showing an excellent photometric and dispensing accuracy, absence of sample-dependent carry-over, and almost negligible reagent carry-over. Good precision, linearity and correlation with routine methods were found for the parameters tested. The instrument is reliable and is now used as the routine clinical chemistry analyser in two of the three laboratories taking part in the evaluation.  相似文献   
6.
7.
作为1 100 kV的UHV(特高压)输电,面临技术--生态环境的巨大挑战.变电站的UHV开关装置模块,需要的是可靠、成本/效益比好、环境友好、可维护的方案.对于这些所需的参数以及技术规范的验证,采用AIS(空气隔离变电所)技术能完全满足这些需要.介绍由瓷柱式断路器、隔离开关和NCIT(非传统互感器)所组成的UHV模块.这些装置是根据模块原理预先设计好的,其中的设备间的连接肯定允许快速安装.在变电站设备控制和检测方面,模块是预制标准化.加拿大和德国的试验站对断路器、隔离开关等独立的开关元件,在1 100 kV上做BIL、SIL和工频等绝缘试验,性能表现非常优越.因为对于特高压电压等级,IEC标准至今尚未规定,所以将根据外推法和现场数据作合理解释.瓷柱式断路器采用了最新复合绝缘体技术,在安全方面有所改进.AIS方案其他的关键技术,例如环境保护和成本,在可比的功能间,根据市场估计价值,与GIS解决方法作了比较.  相似文献   
8.
The thermal and structural stability of the Wells-Dawson-type heteropoly compound K6P2W18O62·10H2O was examined by FT-IR spectroscopy, X-ray powder diffraction, thermogravimetric analysis and HRTEM. It was found that calcination at temperatures higher than 850 K led to the formation of a Keggin-type compound K3PW12O40, containing small amounts of an additional phase originated from the high-temperature interaction between potassium phosphate (K3PO4 formed during the decomposition of the K6P2W18O62·10H2O) and the Keggin-type compound itself. The Keggin-type product showed a higher activity in the selective oxidative dehydrogenation of isobutane to isobutene compared to both the Wells-Dawson precursor and to pure, authentic K3PW12O40. This higher activity can be tentatively attributed to the presence of an amorphous layer of unknown stoichiometry at the surface of the thermally rearranged Wells-Dawson compound.  相似文献   
9.
The International Stripa Project was a cooperative research and development project among several member countries of the Nuclear Energy Agency of the Organization for Economic Cooperation and Development. The scientific and technical objectives of the project were to investigate several aspects of technology concerned with the feasibility and safety of disposal of long-lived, heat-generating radioactive waste at depth in granitic rocks. In particular, the Stripa Project addressed: 1) the development of instruments and procedures to characterize candidate repository sites; 2) the understanding and modelling of groundwater flow and solute transport in fractured crystalline rock; and 3) the design of engineered barriers capable of contributing to waste isolation by restricting groundwater flow in proximity to the waste containers and in the surrounding host rock. This overview summarizes the work focussed on natural barriers and engineered barriers.  相似文献   
10.
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