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   4161篇
  免费   349篇
  国内免费   7篇
电工技术   61篇
综合类   4篇
化学工业   1259篇
金属工艺   87篇
机械仪表   136篇
建筑科学   115篇
矿业工程   7篇
能源动力   157篇
轻工业   922篇
水利工程   40篇
石油天然气   28篇
无线电   215篇
一般工业技术   700篇
冶金工业   370篇
原子能技术   23篇
自动化技术   393篇
  2024年   13篇
  2023年   55篇
  2022年   168篇
  2021年   222篇
  2020年   144篇
  2019年   176篇
  2018年   178篇
  2017年   197篇
  2016年   181篇
  2015年   132篇
  2014年   228篇
  2013年   281篇
  2012年   280篇
  2011年   302篇
  2010年   237篇
  2009年   239篇
  2008年   189篇
  2007年   195篇
  2006年   146篇
  2005年   103篇
  2004年   84篇
  2003年   85篇
  2002年   62篇
  2001年   53篇
  2000年   35篇
  1999年   47篇
  1998年   103篇
  1997年   79篇
  1996年   52篇
  1995年   33篇
  1994年   30篇
  1993年   35篇
  1992年   13篇
  1991年   18篇
  1990年   21篇
  1989年   13篇
  1988年   26篇
  1987年   8篇
  1986年   12篇
  1985年   7篇
  1984年   3篇
  1983年   2篇
  1981年   2篇
  1980年   3篇
  1979年   2篇
  1977年   4篇
  1976年   11篇
  1974年   3篇
  1972年   2篇
  1964年   1篇
排序方式: 共有4517条查询结果,搜索用时 15 毫秒
1.
2.
3.
Debittered trub (brewing waste) is an important source of protein source (70.26%). Trub and whey protein were used for 5% protein enrichment of ice cream frozen by liquid nitrogen. Three formulations were elaborated: ice cream standard (ICS), ice cream with whey protein (ICW) and ice cream with trub (ICT). Chemical composition, rheological properties, texture, overrun, melting rate, scanning electron microscopy and a sensorial test were performed. Results showed that ICT presented a higher viscosity, obtained on the upward curve up to 6.76 Pa s−1, consistency index (22.96 (Pa s−1)n), hysteresis area (140.40 mPa s−1) and hardness (31113.33 g) but a lower melting rate (0.38 g min−1), overrun (13.92%) and sensorial acceptability than the other formulations. The addition of trub debittered for protein enrichment improved ice cream properties and demonstrated that it could be used as a food ingredient.  相似文献   
4.
5.
6.
7.
8.
9.
Radiation therapy is a technology-driven cancer treatment modality that has experienced significant advances over the last decades, due to multidisciplinary contributions that include engineering and computing. Recent technological developments allow the use of noncoplanar volumetric modulated arc therapy (VMAT), one of the most recent photon treatment techniques, in clinical practice. In this work, an automated noncoplanar arc trajectory optimization framework designed in two modular phases is presented. First, a noncoplanar beam angle optimization algorithm is used to obtain a set of noncoplanar irradiation directions. Then, anchored in these directions, an optimization strategy is proposed to compute an optimal arc trajectory. The computational experiments considered a pool of twelve difficult head-and-neck tumor cases. It was possible to observe that, for some of these cases, the optimized noncoplanar arc trajectories led to significant treatment planning quality improvements, when compared with coplanar VMAT treatment plans. Although these experiments were done in a research environment treatment planning software (matRad), the conclusions can be of interest for a clinical setting: automated procedures can simplify the current treatment workflow, produce high-quality treatment plans, making better use of human resources and allowing for unbiased comparisons between different treatment techniques.  相似文献   
10.
Chitosan microspheres containing bromocresol green, cresol red, and phenolphthalein for corrosion detection, through pH change, are synthesized in order to be used in protective coatings for aluminium alloys. Microspheres containing corrosion detection species are characterized morphologically (SEM) and physico‐chemically (FTIR, TGA). Release studies (UV–vis) are performed in corrosion‐promoting conditions (pH, NaCl), and detection studies by immersion in media associated with corrosion activity while microspheres' sensing activity is evaluated visually. Electrochemical characterization of AA2024 substrates in the presence of chitosan spheres is performed to understand material performance, and a color change is observed as a result of local pH increase in cathodic areas when corrosion takes place. These findings can be correlated with the results from release studies and seem a promising approach for corrosion sensing purposes, not only because pH increase is possible to detect due to corrosion, but also because chitosan is considered an environmentally friendly material.  相似文献   
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