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   1904篇
  免费   55篇
  国内免费   2篇
工业技术   1961篇
  2023年   16篇
  2022年   20篇
  2021年   44篇
  2020年   26篇
  2019年   33篇
  2018年   42篇
  2017年   39篇
  2016年   39篇
  2015年   41篇
  2014年   70篇
  2013年   104篇
  2012年   86篇
  2011年   128篇
  2010年   98篇
  2009年   70篇
  2008年   98篇
  2007年   114篇
  2006年   93篇
  2005年   55篇
  2004年   76篇
  2003年   59篇
  2002年   50篇
  2001年   30篇
  2000年   43篇
  1999年   39篇
  1998年   69篇
  1997年   53篇
  1996年   30篇
  1995年   26篇
  1994年   31篇
  1993年   22篇
  1992年   21篇
  1991年   13篇
  1990年   12篇
  1989年   8篇
  1988年   7篇
  1987年   13篇
  1986年   15篇
  1985年   19篇
  1984年   13篇
  1983年   12篇
  1982年   6篇
  1981年   6篇
  1980年   7篇
  1977年   5篇
  1976年   18篇
  1975年   8篇
  1974年   5篇
  1973年   5篇
  1972年   4篇
排序方式: 共有1961条查询结果,搜索用时 0 毫秒
1.
A manufacturing technique for monolithic dye-sensitised solar cells is presented. Encapsulated modules designed for indoor low-power applications have been prepared using industrial methods and equipment. Under certain conditions (light intensity <5000 lx, temperature between –10°C and 50°C, and relative humidity of appr. 50%), the modules have performed well and shown excellent long-term stability. Moreover, modules withstand illumination in combination with storage at 100% relative humidity. However, a certain degradation of the module performance takes place at illuminations exceeding 5000 lx and temperatures exceeding 50°C.  相似文献   
2.
3.
The Jervell and Lange-Nielsen syndrome (JLNS) comprises profound congenital sensorineural deafness associated with syncopal episodes. These are caused by ventricular arrhythmias secondary to abnormal repolarisation, manifested by a prolonged QT interval on the electrocardiogram. Recently, in families with JLNS, Neyroud et al. reported homozygosity for a single mutation in KVLQT1 , a gene which has previously been shown to be mutated in families with dominantly inherited isolated long QT syndrome [Neyroud et al . (1997) Nature Genet ., 15, 186-189]. We have analysed a group of families with JLNS and shown that the majority are consistent with mutation at this locus: five families of differing ethnic backgrounds were homozygous by descent for markers close to the KVLQT1 gene and a further three families from the same geographical region were shown to be homozygous for a common haplotype and to have the same homozygous mutation of the KVLQT1 gene. However, analysis of a single small consanguineous family excluded linkage to the KVLQT1 gene, establishing genetic heterogeneity in JLNS. The affected children in this family were homozygous by descent for markers on chromosome 21, in a region containing the gene IsK . This codes for a transmembrane protein known to associate with KVLQT1 to form the slow component of the delayed rectifier potassium channel. Sequencing of the affected boys showed a homozygous mutation, demonstrating that mutation in the IsK gene may be a rare cause of JLNS and that an indistinguishable phenotype can arise from mutations in either of the two interacting molecules.  相似文献   
4.
This paper describes the implementation of a general and flexible method of formulating problems of mathematical programming in structural optimization systems. The method enables the formulation and solution of problems involving scalar, integral, min/max, max/min and possibly non-differentiable user defined functions in any conceivable mix. The mathematical formulation is based on the bound formulation, and the implementation specific details involve a parser capable of interpreting and performing symbolic differentiation of the user defined functions.  相似文献   
5.
Time-domain limitations due to right half-plane zeros and poles in linear multivariable control systems are studied. Lower bounds on the interaction are derived. They show not only how the location of zeros and poles are critical in multivariable systems, but also how the zero and pole directions influence the performance. The results are illustrated on the quadruple-tank process, which is a new multivariable laboratory process.  相似文献   
6.
7.
8.
9.
Electrochemical impedance spectroscopy was used to determine the effective charge transfer resistances of porous dye-sensitized solar cell counter electrodes prepared by low-temperature spray deposition and compression of conductive carbon and platinized Sb-doped SnO2 powders on indium tin oxide-coated plastic substrates. The charge transfer resistances were 0.5–2 and 8–13 Ω cm2, respectively, when using 3-methoxypropionitrile as the electrolyte solvent. The manufacturing method used lends itself to produce mechanically stable and even-quality electrodes in an easy and fast manner.  相似文献   
10.
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