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   281篇
  免费   11篇
  国内免费   4篇
电工技术   5篇
化学工业   71篇
金属工艺   3篇
机械仪表   13篇
建筑科学   4篇
能源动力   9篇
轻工业   23篇
石油天然气   3篇
无线电   51篇
一般工业技术   71篇
冶金工业   20篇
原子能技术   4篇
自动化技术   19篇
  2023年   3篇
  2022年   12篇
  2021年   10篇
  2020年   5篇
  2019年   13篇
  2018年   9篇
  2017年   14篇
  2016年   10篇
  2015年   12篇
  2014年   9篇
  2013年   23篇
  2012年   25篇
  2011年   13篇
  2010年   11篇
  2009年   15篇
  2008年   13篇
  2007年   12篇
  2006年   11篇
  2005年   9篇
  2004年   6篇
  2003年   6篇
  2002年   6篇
  2001年   3篇
  2000年   3篇
  1999年   3篇
  1998年   8篇
  1997年   7篇
  1996年   6篇
  1995年   2篇
  1993年   2篇
  1992年   2篇
  1991年   2篇
  1990年   1篇
  1988年   1篇
  1986年   1篇
  1985年   1篇
  1979年   2篇
  1977年   1篇
  1975年   3篇
  1973年   1篇
排序方式: 共有296条查询结果,搜索用时 0 毫秒
1.
Sequencing of rice genome has facilitated the understanding of rice evolution and has been utilized extensively for mining of DNA markers to facilitate marker-assisted breeding. Simple sequence repeat (SSR) markers that are tandemly repeated nucleotide sequence motifs flanked by unique sequences are presently the maker of choice in rice improvement due to their abundance, co-dominant inheritance, high levels of allelic diversity, and simple reproducible assay. The current level of genome coverage by SSR markers in rice is sufficient to employ them for genotype identification and marker-assisted selection in breeding for mapping of genes and quantitative trait loci analysis. This review provides comprehensive information on the mapping and applications of SSR markers in investigation of rice cultivars to study their genetic divergence and marker-assisted selection of important agronomic traits.  相似文献   
2.
3.
4.
Growth of ultrathin (<100 Å) oxynitride on strained-Si using microwave N2O and NH3 plasma is reported. X-ray photoelectron spectroscopy (XPS) results indicate a nitrogen-rich layer at the strained-Si/SiO2 interface. The electrical properties of oxynitrides have been characterized using a metal-insulator-semiconductor (MIS) structure. A moderately low value of insulator charge density (6.1×1010 cm-2) has been obtained for NH3 plasma treated N2O oxide sample. Nitrided oxide shows a larger breakdown voltage and an improved charge trapping properties under Fowler-Nordheim (F-N) constant current stress  相似文献   
5.
6.
7.
8.
Journal of Computational Electronics - The strain- and electric field-dependent electronic and&nbsp;optical properties of monolayer GaInS2&nbsp;have been calculated using density functional...  相似文献   
9.
A modification to a Perkin-Elmer model 521 infrared spectrophotometer is described which allows a difference spectrum to be obtained from the same sample of a nerve between resting and excited states. Signal processing using time averaging and digital smoothing are employed to improve the signal-to-noise ratio (S/N).  相似文献   
10.
Present study highlights the development of carbon-loaded SBA 15 membrane on clay-alumina tubular support and its performance on the CO2 separation efficiencies from different mixture gases. To modify the large pores of SBA 15 by graphitic carbon, low molecular weight phenol–formaldehyde (PF) resin was incorporated into the mesoporous channel followed by calcination under inert atmosphere. The modified ordered pore structure of the membrane has been characterized by low-angle XRD, TEM, and pore size distribution analysis. The chemical state of the deposited carbon phase into the SBA 15 pores was analyzed by X-ray photoelectron and Raman spectroscopy. Carbon having graphitic nature mainly in graphene oxide has been deposited into the mesopore of SBA 15 resulting decrease in pore size from 8.9 to 1.0 nm. Finally, the developed SBA 15 carbon membranes were characterized by CO2 permeation and separation selectivity of CO2/CH4, CO2/CO. Highest CO2/CH4 separation factor was achieved as 16.9 with CO2 permeance 13.6 × 10–8 mol/m2/s/Pa at 200 kPa feed pressure by the 20% resin with 2 times coated membrane. In flue gas analysis, highest CO2/CO separation factor of 32.8 was achieved. This study offers an observation on CO2 separation from simulated BF gas for the first time and the results show the potential of the developed SBA 15/C composite membranes in commercial application.  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