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   330825篇
  免费   5893篇
  国内免费   874篇
电工技术   5361篇
综合类   200篇
化学工业   55126篇
金属工艺   12750篇
机械仪表   9489篇
建筑科学   8221篇
矿业工程   1931篇
能源动力   7942篇
轻工业   33208篇
水利工程   3570篇
石油天然气   7276篇
武器工业   23篇
无线电   33271篇
一般工业技术   63715篇
冶金工业   60078篇
原子能技术   7767篇
自动化技术   27664篇
  2021年   3298篇
  2019年   2996篇
  2018年   5128篇
  2017年   5063篇
  2016年   5499篇
  2015年   3716篇
  2014年   5828篇
  2013年   15109篇
  2012年   9293篇
  2011年   11888篇
  2010年   9635篇
  2009年   10684篇
  2008年   10788篇
  2007年   10446篇
  2006年   9093篇
  2005年   8409篇
  2004年   7841篇
  2003年   7457篇
  2002年   7480篇
  2001年   7103篇
  2000年   6753篇
  1999年   6863篇
  1998年   17397篇
  1997年   12845篇
  1996年   9772篇
  1995年   7265篇
  1994年   6519篇
  1993年   6457篇
  1992年   4729篇
  1991年   4706篇
  1990年   4461篇
  1989年   4496篇
  1988年   4438篇
  1987年   3783篇
  1986年   3761篇
  1985年   4350篇
  1984年   4116篇
  1983年   3738篇
  1982年   3565篇
  1981年   3720篇
  1980年   3599篇
  1979年   3449篇
  1978年   3537篇
  1977年   4240篇
  1976年   5704篇
  1975年   3222篇
  1974年   3060篇
  1973年   3096篇
  1972年   2675篇
  1971年   2509篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
In this study, amaranth flour was used as an ingredient to prepare gluten-free cookies. The production process and attributes of amaranth cookies were characterised, and the potential use of amaranth flour as a functional ingredient was analysed. Cookies exhibited a non-uniform reddish brown colour and a cookie factor ratio of 4.5 ± 0.6. Storage studies indicated that after 3 weeks at room temperature cookies presented slight variations in the texture. Simulated gastrointestinal digestion of this product was able to release peptides capable of exerting potential antithrombotic and antihypertensive activities, IC50 values of 0.22 ± 0.04 and 0.23 ± 0.03 mg mL−1 protein, respectively. This work demonstrates for the first time that food made with amaranth flour exerts potential antithrombotic and antihypertensive activity. In conclusion, these amaranth cookies could be an alternative way of incorporating potentially health beneficial products for people who choose a conscious diet, including coeliac or vegan consumers.  相似文献   
42.
43.
44.
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   
45.
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   
46.
Seed processing technologies are essential for seed safety and functionality through protection of physicochemical quality, pathogen inactivation, aflatoxin detoxification and alleviation of mutagenicity. Design of a pilot-scale unit of pulsed electric fields (PEF) to treat sesame seeds with respect to quality parameters, Aspergillus parasiticus inactivation and aflatoxin reduction as well as alleviation of aflatoxin mutagenicity were prompted in this study. PEF energy ranged from 0.97 to 17.28 J achieved maximum reductions of peroxide value and acidity number of 67.4 and 85.7%, respectively, and did not change color L*, a*, b* and hue values. A 60% reduction of A. parasiticus counts occurred at the maximum PEF energy. Aflatoxins G1, G2, B1, and B2 contents decreased by 94.7, 92.7, 86.9, and 98.7%, respectively. Except for the samples treated by 2.16 J with 100 μg/plate and by 6.80 J with 10 μg/plate, PEF treatment provided elimination of aflatoxin mutagenity. It is concluded that PEF treatment can be used to treat sesame seeds with preservation of physicochemical properties, inactivation of A. parasiticus and decomposition of aflatoxins with reduced mutagenicity.  相似文献   
47.
Theoretical Foundations of Chemical Engineering - The extraction of nitric and oxalic acids by neutral compounds TBP, DBBP, and TBPO have been studied. The optimal conditions of their separation...  相似文献   
48.
Neural Computing and Applications - This study presents the design of a tenth-order multiple feedback Chebyshev low-pass filter (MF-C-LPF). Component selection and gain calculation of filters are...  相似文献   
49.
50.
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