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   693篇
  免费   1篇
电工技术   14篇
综合类   2篇
化学工业   135篇
金属工艺   66篇
机械仪表   37篇
建筑科学   10篇
矿业工程   6篇
能源动力   4篇
轻工业   2篇
水利工程   13篇
石油天然气   23篇
无线电   27篇
一般工业技术   170篇
冶金工业   76篇
原子能技术   90篇
自动化技术   19篇
  2022年   7篇
  2021年   22篇
  2020年   10篇
  2019年   10篇
  2018年   18篇
  2017年   19篇
  2016年   17篇
  2015年   8篇
  2014年   20篇
  2013年   17篇
  2012年   25篇
  2011年   21篇
  2010年   15篇
  2009年   20篇
  2008年   17篇
  2007年   25篇
  2006年   21篇
  2005年   18篇
  2004年   16篇
  2003年   11篇
  2002年   15篇
  2001年   16篇
  2000年   13篇
  1999年   6篇
  1998年   8篇
  1997年   9篇
  1996年   20篇
  1995年   11篇
  1994年   15篇
  1992年   11篇
  1991年   14篇
  1990年   6篇
  1989年   7篇
  1988年   17篇
  1987年   11篇
  1985年   7篇
  1984年   12篇
  1983年   7篇
  1982年   10篇
  1981年   12篇
  1980年   11篇
  1978年   9篇
  1977年   10篇
  1976年   14篇
  1975年   10篇
  1974年   16篇
  1973年   9篇
  1972年   10篇
  1967年   4篇
  1965年   4篇
排序方式: 共有694条查询结果,搜索用时 183 毫秒
1.
Russian Microelectronics - The recently developed nanomaterials and their production technologies as intellectual property objects (IPOs) are considered. The role of the informational-analytical...  相似文献   
2.
Biodegradable implants are required in order to provide successful treatment of injuries. Temporary magnesium‐based implants with particular properties are needed in cases when it is desirable not only to maintain vital activity, but also to initiate the self‐healing process of damaged bones or tissues as well. Unfortunately, the use of magnesium alloys is limited due to the fast biodegradability of the applied material. The aim of this research is to improve the corrosion resistance of magnesium alloys by sonochemical treatment in silk solution followed by additional layer‐by‐layer deposition of natural silk on the magnesium surface. The sonication process is carried out at a frequency of 20 kHz during 5–10 min, while the duration of the silk layer deposition is 15 min. The corrosion behavior of magnesium substrates modified by natural silk layer‐by‐layer assembly is studied. Magnesium substrates sonochemically treated in silk solution demonstrate three times better corrosion resistance compared to control samples sonochemically treated in water. Additional deposition of a silk layer enhances obtained corrosion resistance by 18 times, resulting in a 54‐fold increase overall.  相似文献   
3.
This paper investigates how the recent crisis of 2008 changed relations between innovation and firm performance in Western Europe. We apply a structural framework of CDM modelling, which incorporates different stages of the knowledge creation process and takes into account the complex nature of innovations. The study is based on a balanced panel data of 420 listed manufacturing firms from the U.K., Germany and France. All the information is gathered from common sources, thereby reducing subjectivity, a typical problem in the field. We found, the crisis resulted in appreciable changes in the model. The most important evidence is enhancement of the role of firm resources in the post-recession period. We also reveal larger barriers for innovations, increased uncertainty and lower state dependence in R&D engagement, product creation and economic performance. These results could indicate the ‘cleaning effect’ of the crisis, which has worsened the business environment and enhanced competition.  相似文献   
4.
Protection of Metals and Physical Chemistry of Surfaces - The passivating properties of various polymer matrices have been studied for a metal-polymer composite prepared by intensive plastic...  相似文献   
5.
Protection of Metals and Physical Chemistry of Surfaces - Based on the concept of collective vibrations of ions in the bulk of metal systems, the frequency of vibrations of an oxygen molecule on...  相似文献   
6.
Protection of Metals and Physical Chemistry of Surfaces - Powdered mixtures of aluminum with 20 wt % of organic components were subjected to plastic deformation under a pressure of 0.5–4.0...  相似文献   
7.
8.
9.
MicroRNAs (miRNAs) are short, single-stranded, non-coding ribonucleic acid (RNA) molecules, which are involved in the regulation of main biological processes, such as apoptosis or cell proliferation and differentiation, through sequence-specific interaction with target mRNAs. In this study, we propose a workflow for predicting miRNAs function by analyzing the structure of the network of their target genes. This workflow was applied to study the functional role of miR-375 in the heart muscle (myocardium), since this miRNA was previously shown to be associated with heart diseases, and data on its function in the myocardium are mostly unclear. We identified PIK3CA, RHOA, MAPK3, PAFAH1B1, CTNNB1, MYC, PRKCA, ERBB2, and CDC42 as key genes in the miR-375 regulated network and predicted the possible function of miR-375 in the heart muscle, consisting mainly in the regulation of the Rho-GTPases-dependent signaling pathways. We implemented our algorithm for miRNA function prediction into a Python module, which is available at GitHub.  相似文献   
10.
Russian Engineering Research - Basic types of auxiliary drives in automated assembly systems are compared in terms of generalized characteristics. Regulation of the pneumatic drive by means of...  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