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   256248篇
  免费   5417篇
  国内免费   617篇
电工技术   3888篇
综合类   208篇
化学工业   40867篇
金属工艺   11181篇
机械仪表   7991篇
建筑科学   5823篇
矿业工程   2271篇
能源动力   5821篇
轻工业   18744篇
水利工程   3344篇
石油天然气   7896篇
武器工业   26篇
无线电   24641篇
一般工业技术   54449篇
冶金工业   45970篇
原子能技术   6898篇
自动化技术   22264篇
  2021年   3360篇
  2020年   2586篇
  2019年   2978篇
  2018年   5540篇
  2017年   5514篇
  2016年   5940篇
  2015年   3675篇
  2014年   5618篇
  2013年   12276篇
  2012年   8762篇
  2011年   10353篇
  2010年   8203篇
  2009年   8616篇
  2008年   9023篇
  2007年   8670篇
  2006年   7201篇
  2005年   6502篇
  2004年   5821篇
  2003年   5649篇
  2002年   5353篇
  2001年   5091篇
  2000年   4775篇
  1999年   4931篇
  1998年   13404篇
  1997年   9160篇
  1996年   6675篇
  1995年   4953篇
  1994年   4324篇
  1993年   4519篇
  1992年   3252篇
  1991年   3239篇
  1990年   3199篇
  1989年   3137篇
  1988年   3090篇
  1987年   2718篇
  1986年   2818篇
  1985年   3124篇
  1984年   2928篇
  1983年   2731篇
  1982年   2514篇
  1981年   2505篇
  1980年   2542篇
  1979年   2528篇
  1978年   2528篇
  1977年   2734篇
  1976年   3318篇
  1975年   2303篇
  1974年   2159篇
  1973年   2261篇
  1972年   2002篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
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   
52.
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   
53.
Theoretical Foundations of Chemical Engineering - The development of a thermostable hydrophobic platinum catalyst is an important scientific and practical problem. The purpose of this work is to...  相似文献   
54.
The basic stages in the life cycle of a batch of complex engineering products are considered: design, production, operation, and disposal. A priori cost assessment for each stage is discussed. The cost aggregation in the consideration of multiple stages is analyzed. Requirements on the assessment are formulated. Methodological and implementation aspects of the assessment tools are outlined. The conclusion is that it is expedient to predict the costs on the basis of mathematical models of the product batch in an operational environment. The integration of multiple cost estimates is addressed.  相似文献   
55.
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   
56.
Russian Journal of Non-Ferrous Metals - Rolling bearing rings comprise a large reserve for expanding powder metallurgy production. This reserve is being incompletely implemented. The hot forging of...  相似文献   
57.
Photonic Network Communications - Optical packet switching is a prominent technology proposing not only a reduction in the energy consumption by the elimination of numerous...  相似文献   
58.
59.
60.
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