首页 | 官方网站   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   426篇
  免费   6篇
工业技术   432篇
  2019年   3篇
  2018年   2篇
  2017年   3篇
  2016年   3篇
  2015年   7篇
  2014年   3篇
  2013年   27篇
  2012年   9篇
  2011年   13篇
  2010年   17篇
  2009年   25篇
  2008年   12篇
  2007年   13篇
  2006年   11篇
  2005年   14篇
  2004年   16篇
  2003年   11篇
  2002年   13篇
  2001年   9篇
  2000年   12篇
  1999年   11篇
  1998年   17篇
  1997年   15篇
  1996年   15篇
  1995年   13篇
  1994年   9篇
  1993年   8篇
  1992年   7篇
  1991年   7篇
  1990年   7篇
  1989年   3篇
  1988年   4篇
  1987年   3篇
  1986年   2篇
  1985年   6篇
  1984年   2篇
  1983年   5篇
  1982年   7篇
  1981年   5篇
  1980年   4篇
  1979年   13篇
  1978年   2篇
  1977年   6篇
  1976年   9篇
  1975年   3篇
  1974年   4篇
  1973年   2篇
  1972年   4篇
  1966年   2篇
  1964年   3篇
排序方式: 共有432条查询结果,搜索用时 15 毫秒
1.
The objective of this study was to determine the effect of complexation of oxidised starch with mineral elements on its physicochemical properties. Corn starch was oxidised with sodium hypochlorite and, afterwards, modified with ions of potassium, magnesium and iron. Thus, native and modified starches were analysed for: contents of mineral elements, colour parameters (L*a*b*), water binding capacity and solubility in water at temperature of 60 and 80 °C. Thermodynamic characteristics of gelatinisation by DSC, molecular weight distribution by GPC, intrinsic viscosity and pasting properties by RVA were studied. The efficiency of incorporation of metal ions into oxidised corn starch was about 30%, 20% and 20% for potassium, magnesium and iron ions, respectively. The complexation with potassium ions caused the greatest changes in the molecular weight distribution and the intrinsic viscosity of starches and viscosity of starch pastes. Only modification of starch with iron ions affected the colour parameters of the starch. Incorporation of metal ions into starch resulted also in changes in its water binding capacity and solubility in water.  相似文献   
2.
3.
The noise of aerodynamics nature from modern transonic fan is examined from its sources with the perspective of noise reduction through aero-acoustics design using advanced Computational Fluid Dynamics (CFD) tools. In particular the problems associated with the forward propagating noise in the front is addressed. It is identified that the shock wave spillage from the leading edge near the fan tip is the main source of the tone noise. Two different approaches have been studied to reduce the forward arc tone noise and two state-of-art transonic fans are designed using the strategies developed. The following rig tests show that while the fans exhibit other noise problems, the primary goals of noise reduction have been achieved through both fans and the novel noise reduction concept vindicated.  相似文献   
4.
BACKGROUND: In a series of 229 patients infected with mycobacterial organisms, we noted a specific female phenotype that involves isolated infections of the middle lobe and lingula. METHODS: Thirteen patients were found to have infections of the middle lobe, lingula, or both. All of them were infected with Mycobacterium other then Mycobacterium tuberculosis, all were women, 12 of the 13 were slender, and most had variable combinations of skeletal abnormalities. All underwent resection of the middle lobe, lingula, or both. RESULTS: There were no operative deaths. Only 2 patients have had reactivation requiring additional antibiotic therapy. All patients have had a decreased number of pulmonary infections in the postoperative period. Anatomic findings at operation included a complete major fissure and at least a partially complete minor fissure with middle lobe resections or an elongated lingula. CONCLUSIONS: Mycobacterial infection of the middle lobe and lingula is primarily a disease of asthenic women and is often associated with skeletal abnormalities and complete fissures or an elongated lingula. We recommend that surgical intervention be performed early once the condition is identified.  相似文献   
5.
6.
A very simple algorithm for computing all k nearest neighbors in 2-D is presented. The method does not rely on complicated forms of tessellation, it only requires simple data binning for fast range searching. Its applications range from scattered data interpolation to reverse engineering.  相似文献   
7.
Advances in distributed architectures and the Internet have had a strong influence on the use of component technologies. The authors discuss the organizational and technical requirements for an effective and economically viable component-based approach.  相似文献   
8.
The portability of software has become a major commercial issue in recent times. Such portability does not come easily, as few if any computer languages are really portable in practice. An additional complicating factor, especially in the commercial environment, is that the resulting software must be efficient. This paper describes the design and successful implementation of a 500,000+ line portable FORTRAN 77 package for the processing of seismic data. The package exhibits demonstrably high efficiency on a wide variety of machines from minicomputers to the largest supercomputers. Experiences gained during this exercise throw much light on the integration of the various thought processes which occur during the software engineering cycle, especially the notion of locality.  相似文献   
9.
10.
Les Hatton 《Computer》2007,40(2):64-69
Research shows considerable overlap among perfective, corrective, and adaptive maintenance tasks in software development projects. A case study involving two recent products provides further empirical evidence of this distribution and sheds light on how well programmers estimate both the type of maintenance necessary and the duration with some significant surprises  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-23

京公网安备 11010802026262号