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   2131篇
  免费   89篇
  国内免费   2篇
电工技术   66篇
综合类   15篇
化学工业   364篇
金属工艺   76篇
机械仪表   17篇
建筑科学   64篇
矿业工程   22篇
能源动力   22篇
轻工业   762篇
水利工程   8篇
石油天然气   3篇
无线电   74篇
一般工业技术   329篇
冶金工业   46篇
原子能技术   12篇
自动化技术   342篇
  2023年   28篇
  2022年   34篇
  2021年   70篇
  2020年   37篇
  2019年   44篇
  2018年   78篇
  2017年   56篇
  2016年   82篇
  2015年   57篇
  2014年   87篇
  2013年   107篇
  2012年   73篇
  2011年   63篇
  2010年   98篇
  2009年   94篇
  2008年   71篇
  2007年   80篇
  2006年   43篇
  2005年   24篇
  2004年   26篇
  2003年   30篇
  2002年   23篇
  2001年   22篇
  2000年   17篇
  1999年   20篇
  1998年   31篇
  1997年   22篇
  1994年   14篇
  1943年   18篇
  1942年   14篇
  1940年   13篇
  1939年   13篇
  1936年   18篇
  1935年   13篇
  1934年   16篇
  1932年   13篇
  1931年   13篇
  1930年   15篇
  1929年   13篇
  1928年   16篇
  1927年   12篇
  1925年   19篇
  1924年   27篇
  1923年   20篇
  1918年   28篇
  1917年   31篇
  1916年   26篇
  1915年   34篇
  1911年   14篇
  1910年   15篇
排序方式: 共有2222条查询结果,搜索用时 15 毫秒
101.
102.
103.
104.
105.
Gaining a better understanding of human–computer interaction in multiple-goal environments, such as driving, is critical as people increasingly use information technology to accomplish multiple tasks simultaneously. Extensive research shows that decision biases can be utilized as effective cues to guide user interaction in single-goal environments. This article is a first step toward understanding the effect of decision biases in multiple-goal environments. This study analyzed data from a field experiment during which a comparison was made between drivers’ decisions on parking lots in a single-goal environment and drivers’ decisions in a multiple-goal environment when being exposed to the default option bias. The article shows that the default option bias is effective in multiple-goal environments. The results have important implications for the design of human–computer interaction in multiple-goal environments.  相似文献   
106.
107.
108.
109.
There is currently no suitable replacement for damaged temporomandibular joint (TMJ) discs after discectomy. In the present study, we fabricated bilayer biodegradable polylactide (PLA) discs comprising a non-woven mat of poly(L/D)lactide (P(L/D)LA) 96/4 and a P(L/DL)LA 70/30 membrane plate. The PLA disc was examined in combination with adipose stem cells (ASCs) for tissue engineering of the fibrocartilaginous TMJ disc in vitro. ASCs were cultured in parallel in control and chondrogenic medium for a maximum of six weeks. Relative expression of the genes, aggrecan, type I collagen and type II collagen present in the TMJ disc extracellular matrix increased in the ASC-seeded PLA discs in the chondrogenic medium. The hypertrophic marker, type X collagen, was moderately induced. Alcian blue staining showed accumulation of sulphated glycosaminoglycans. ASC differentiation in the PLA discs was close to that observed in pellet cultures. Comparison of the mRNA levels revealed that the degree of ASC differentiation was lower than that in TMJ disc-derived cells and tissue. The pellet format supported the phenotype of the TMJ disc-derived cells under chondrogenic conditions and also enhanced their hyalinization potential, which is considered part of the TMJ disc degeneration process. Accordingly, the combination of ASCs and PLA discs has potential for the development of a tissue-engineered TMJ disc replacement.  相似文献   
110.
The spray-drying behaviour of 16 water-miscible organic solvents on a bench-scale machine (Büchi B290 with inert loop) was determined under mild-to-moderate process conditions, namely inlet gas temperature of 130?°C and liquid feed flow rate of ≤3?mL/min. The solvents with boiling points below the inlet gas temperature could be fully dried (Group 1 solvents). The two exceptions were DMSO and DMF which despite their higher boiling points could be fully dried. The remaining solvents with boiling points above the inlet gas temperature were not fully dried during passage through the spray-dryer (Group 2 solvents). Trypsin and lysozyme when spray-dried from Group 1 solvent binary mixtures with water showed similar inactivation and residual water content, independent of solvent. The level of residual solvent was, however, strongly dependent on solvent. Trehalose (20%) and mannitol (10%) could be spray-dried from DMSO/water binary mixtures, but the amorphous disaccharide required higher inlet gas temperature. Trehalose/trypsin and mannitol/trypsin formulations showed differing degrees of protection against enzyme inactivation when spray-dried from Group 1 solvent binary mixtures with water. In all solvents the mannitol protected as well, if not better, than the trehalose. This study identifies some suitable organic solvents for spray-drying protein formulations, but also shows the difficulties of remaining organic solvent under the moderate inlet gas temperature used.  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