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   1472篇
  免费   124篇
  国内免费   1篇
电工技术   7篇
综合类   8篇
化学工业   382篇
金属工艺   37篇
机械仪表   48篇
建筑科学   49篇
矿业工程   6篇
能源动力   62篇
轻工业   255篇
水利工程   17篇
石油天然气   8篇
武器工业   6篇
无线电   97篇
一般工业技术   239篇
冶金工业   71篇
原子能技术   5篇
自动化技术   300篇
  2024年   4篇
  2023年   13篇
  2022年   53篇
  2021年   68篇
  2020年   45篇
  2019年   41篇
  2018年   75篇
  2017年   66篇
  2016年   59篇
  2015年   49篇
  2014年   52篇
  2013年   113篇
  2012年   107篇
  2011年   125篇
  2010年   99篇
  2009年   87篇
  2008年   91篇
  2007年   80篇
  2006年   49篇
  2005年   51篇
  2004年   32篇
  2003年   23篇
  2002年   33篇
  2001年   15篇
  2000年   13篇
  1999年   19篇
  1998年   33篇
  1997年   20篇
  1996年   10篇
  1995年   9篇
  1994年   10篇
  1993年   6篇
  1992年   9篇
  1991年   5篇
  1990年   4篇
  1989年   3篇
  1988年   5篇
  1987年   2篇
  1986年   2篇
  1985年   2篇
  1982年   3篇
  1981年   1篇
  1980年   1篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1976年   2篇
  1974年   1篇
  1973年   1篇
  1972年   1篇
排序方式: 共有1597条查询结果,搜索用时 15 毫秒
1.
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   
2.
3.
International Journal of Information Security - Data integrity is a critical security issue in cloud storage. The data integrity checking schemes by a third-party auditor (TPA) have attracted a lot...  相似文献   
4.
Complexation of chitosan in aqueous solutions by low molecular weight electrolytes is one of the simplest methods for the preparation of aqueous chitosan dispersions. In this work, the influence of storage time, sulfate concentration, method of preparation and surfactant content on some properties of the resultant chitosan dispersions (turbidity, viscosity and zeta potential) was analyzed. Turbidimetry was adequate to monitor the formation of particles, while viscometry was suitable to monitor changes in the dispersing phase. An analysis of the properties of these systems, mainly in terms of particle–particle and macromolecule–macromolecule interactions was carried out. Copyright © 2004 Society of Chemical Industry  相似文献   
5.
This paper investigates the effects of processing and equipment parameters of a ribbon blender (i.e. loading method of lubricant, fill level, blade speed and blade design) on magnesium stearate homogeneity. A core sampling technique is used to obtain at least one hundred samples per sampling event, which are extracted throughout the blender and yield a thorough characterization of the entire bed. The results presented here can be used as a guideline to develop appropriate blending processes and characterization protocols for ribbon blenders.  相似文献   
6.
Summary This article deals with the handy synthesis of sulfonyl resins, which were produced by the treatment of a commercial sulfonic resin (Lewatit VPOC1812® based at divinylbenzene (DVB) and styrene (STY). The preliminary chemical modification was based on the reaction of the Lewatit VPOC1812® with thionyl chloride aiming to produce the sulfonyl chloride groups. The best conditions to obtain the sulfonyl chloride groups were: SOCl2/SO3H (molar ratio) =13 at 79 °C during 72 h. The resin chlorinated was afterward treated with urea, thiourea or guanidine. The functionalized resins with urea, thiourea or guanidine were produced with 56, 68 and 93% yield, respectively. The commercial and modified resins were characterized by apparent density, swelling degree, elemental analysis (CHNS), FTIR, optical microscopy (OM) and scanning electron microscopy (SEM).  相似文献   
7.
8.
Image and geometry processing applications estimate the local geometry of objects using information localized at points. They usually consider information about the tangents as a side product of the points coordinates. This work proposes parabolic polygons as a model for discrete curves, which intrinsically combines points and tangents. This model is naturally affine invariant, which makes it particularly adapted to computer vision applications. As a direct application of this affine invariance, this paper introduces an affine curvature estimator that has a great potential to improve computer vision tasks such as matching and registering. As a proof-of-concept, this work also proposes an affine invariant curve reconstruction from point and tangent data.  相似文献   
9.
管内覆丝网强化对流换热及阻力特性的实验研究   总被引:1,自引:1,他引:0  
通过实验对管内覆丝网管进行了强迫对流换热和阻力特性研究。结果表明:管内覆丝网使换热明显增强,阻力也相应增长。菱形丝网对角线距离与平行边距离之比对换热效果有决定作用,丝网厚度对换热的影响比较小,而丝网网格的大小对换热几乎没有影响,在相同的泵功率和几何条件下,换热系数最大增加21%。  相似文献   
10.
Peculiarities of the material composition and physicomechanical characteristics of specific swelling soils are discussed. The authors studied processes of swelling and shrinking and quantitative changes in the soils' properties as a result of these processes in laboratory and field conditions. Dnepropetrovsk Construction Engineering Institute. Translated from Osnovaniya. Fundamenty i Mekhanika Gruntov, No. 2, pp. 24–26, March–April, 1994.  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