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   794400篇
  免费   9943篇
  国内免费   1736篇
电工技术   13809篇
综合类   2994篇
化学工业   124181篇
金属工艺   32901篇
机械仪表   25484篇
建筑科学   18460篇
矿业工程   5578篇
能源动力   18812篇
轻工业   65482篇
水利工程   9571篇
石油天然气   17361篇
武器工业   65篇
无线电   84232篇
一般工业技术   156913篇
冶金工业   129913篇
原子能技术   17744篇
自动化技术   82579篇
  2021年   6508篇
  2019年   6260篇
  2018年   24126篇
  2017年   23274篇
  2016年   20685篇
  2015年   7725篇
  2014年   12334篇
  2013年   32543篇
  2012年   21931篇
  2011年   34407篇
  2010年   28182篇
  2009年   28168篇
  2008年   29695篇
  2007年   30376篇
  2006年   20589篇
  2005年   19454篇
  2004年   18617篇
  2003年   18266篇
  2002年   17230篇
  2001年   16380篇
  2000年   15863篇
  1999年   15546篇
  1998年   36443篇
  1997年   26209篇
  1996年   20423篇
  1995年   15732篇
  1994年   14147篇
  1993年   13844篇
  1992年   10829篇
  1991年   10335篇
  1990年   10350篇
  1989年   10109篇
  1988年   9742篇
  1987年   8688篇
  1986年   8525篇
  1985年   9714篇
  1984年   8941篇
  1983年   8440篇
  1982年   7689篇
  1981年   7813篇
  1980年   7545篇
  1979年   7523篇
  1978年   7444篇
  1977年   8279篇
  1976年   10482篇
  1975年   6720篇
  1974年   6410篇
  1973年   6531篇
  1972年   5585篇
  1971年   5198篇
排序方式: 共有10000条查询结果,搜索用时 17 毫秒
81.
82.
83.
84.
This study aimed to evaluate the physicochemical characteristics and sensory attributes of beef burgers with the addition of pea fibre as a partial substitute of meat or fat. Three formulations were prepared: control (CON) – similar to the commercial formulation; fibre/less meat (FLM)—5% meat reduction and addition of 1% pea fibre; fibre/less fat (FLF)—7% fat reduction and addition of 1% pea fibre. Non-significant differences were obtained for pH, colour parameters (L* and b*), texture profile, cooking loss and size reduction among formulations. Moreover, sensory analysis with consumers of beef burgers did not indicate differences among the formulations for all the analysed attributes. Therefore, pea fibre is a promising partial replacer for meat and fat in beef burgers due to the preservation of technological parameters and sensory acceptance.  相似文献   
85.
86.
Theoretical Foundations of Chemical Engineering - New research results, as well as those published earlier by the authors, on the synthesis of azo compounds based on nitroanilines obtained by the...  相似文献   
87.
In the future, hydrogen will be an important energy carrier and industrial raw material. Catalytic steam reforming of bio-oils is a promising and economically viable technology for hydrogen production. However, during the reforming process, the catalysts are rapidly deactivated due to coke formation and sintering. Thus, maintaining the activity and stability of catalysts is the key issue in this process. Optimized operation conditions could extend the catalyst lifetime by affecting the coke morphology or promoting coke gasification. This article summarizes the recent developments in the field of catalytic steam reforming of bio-oils, focusing on the operation conditions, the properties of the catalysts, and the effects of the catalyst supports. The expected insights into the catalytic steam reforming of bio-oils will provide further guidance for hydrogen production from bio-oils.  相似文献   
88.
Polymer Bulletin - In this study, we synthesized a new ion-imprinted polymer (IIP) based on introduction of amidoxime groups in acrylonitrile, complexation with Cd2+ ions and polymerization with...  相似文献   
89.
At the hydroelectric unit No. 11 of the Nizhnekamsk hydroelectric power plant, the filling wedges of a rotor were investigated by ultrasound in the free st  相似文献   
90.
The bromodomain and extra terminal (BET) family of bromodomain-containing proteins (BCPs) have been the subject of extensive research over the past decade, resulting in a plethora of high-quality chemical probes for their tandem bromodomains. In turn, these chemical probes have helped reveal the profound biological role of the BET bromodomains and their role in disease, ultimately leading to a number of molecules in active clinical development. However, the BET subfamily represents just 8/61 of the known human bromodomains, and attention has now expanded to the biological role of the remaining 53 non-BET bromodomains. Rapid growth of this research area has been accompanied by a greater understanding of the requirements for an effective bromodomain chemical probe and has led to a number of new non-BET bromodomain chemical probes being developed. Advances since December 2015 are discussed, highlighting the strengths/caveats of each molecule, and the value they add toward validating the non-BET bromodomains as tractable therapeutic targets.  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