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   7791篇
  免费   393篇
  国内免费   24篇
工业技术   8208篇
  2023年   69篇
  2022年   41篇
  2021年   155篇
  2020年   153篇
  2019年   139篇
  2018年   192篇
  2017年   186篇
  2016年   217篇
  2015年   163篇
  2014年   270篇
  2013年   362篇
  2012年   444篇
  2011年   510篇
  2010年   360篇
  2009年   410篇
  2008年   370篇
  2007年   305篇
  2006年   230篇
  2005年   223篇
  2004年   187篇
  2003年   166篇
  2002年   166篇
  2001年   120篇
  2000年   108篇
  1999年   150篇
  1998年   785篇
  1997年   409篇
  1996年   302篇
  1995年   183篇
  1994年   143篇
  1993年   163篇
  1992年   38篇
  1991年   40篇
  1990年   48篇
  1989年   54篇
  1988年   51篇
  1987年   41篇
  1986年   26篇
  1985年   22篇
  1984年   4篇
  1983年   10篇
  1982年   11篇
  1981年   17篇
  1980年   14篇
  1979年   3篇
  1978年   2篇
  1977年   29篇
  1976年   109篇
  1975年   2篇
  1955年   1篇
排序方式: 共有8208条查询结果,搜索用时 203 毫秒
31.
Journal of Mechanical Science and Technology - Creep behavior of 316L stainless steel was experimentally investigated using small punch (SP) specimens produced by the selective laser melting (SLM)...  相似文献   
32.
Journal of Mechanical Science and Technology - In this study, the effects of process parameters on the high temperature strength of 17-4PH stainless steel manufactured by selective laser melting...  相似文献   
33.
Food Science and Biotechnology - In this study, we aimed to determine the potential functional properties and biological activities of the hydrolysates of perilla seed meal (PSM), which is a...  相似文献   
34.
In this study, we developed a multiphysics model for simulation of a gas-assisted melt-electrospinning (GAME) process, focusing on jet formation and propagation behavior. By numerically calculating the stresses acting on the jet during a single-nozzle GAME process, the shear viscous stress was identified as the main factor with respect to jet stretch; thus, the relationship between shear viscous stress and jet thickness was investigated. The jet stretch ratio increased sharply when shear viscous stress reached the level at which jet sharpening occurred, leading to stable jet formation. We defined this stress as the critical shear viscous stress to determine stable spinnability. By imposing an electric field distribution calculated for a multi-nozzle array (number of nozzles, tip-to-tip distance, and applied voltage) on the boundary condition of the single-nozzle GAME simulation model, multinozzle GAME was simulated; this enabled proposal of a spinnability diagram for stable spinning.  相似文献   
35.
36.
37.
The lithium metal battery has attracted considerable attention as the ultimate lithium secondary battery for high energy density. However, safety issues and battery performance deterioration due to the growth of lithium dendrites have hampered the practical use of lithium metal batteries. Recently, lithium fluoride has been considered as a lithium metal protective layer to solve this problem. In this review, firstly, the results of the studies on dendrites and SEI that have been carried out to date are reviewed. Secondly, the results of studies on lithium fluoride are divided into additive, artificial SEI, and other methods and the possibilities of their practical use are discussed. Finally, the significance and limitations of the lithium fluoride studies are summarized, and general conclusions and prospects for recommended research directions to accelerate the commercialization of lithium metal batteries are presented.  相似文献   
38.
A reduction process in the head-end for pyroprocessing has been adopted to avoid oxidation attack on the molybdenum crucible during sintering. The reduction process is employed to reduce U3O8 pellets to UO2 prior to sintering. This allows elimination of the oxygen source, which causes oxidation attack during sintering, thereby permitting the use of a metallic crucible. However, little densification occurs due to the low reduction temperature limited by the INCONEL crucible. Consequently, the amount of material scraps from the pellets increases, thus creating an additional processing burden due to its high radioactivity. To reduce the amount of scraps, densification should be enhanced. This study suggests a simple atmospheric control strategy and clarifies its effects. With the atmospheric control, a higher bulk density and better attrition resistance were obtained in comparison to without this strategy. This can be explained in terms of O/U ratio dependent diffusion kinetics during the reduction of U3O8 to UO2.  相似文献   
39.
Stem cell therapy is one of the most promising candidate treatments for spinal cord injury. Research has shown optimistic results for this therapy, but clinical limitations remain, including poor viability, engraftment, and differentiation. Here, we isolated novel peripheral nerve-derived stem cells (PNSCs) from adult peripheral nerves with similar characteristics to neural-crest stem cells. These PNSCs expressed neural-crest specific markers and showed multilineage differentiation potential into Schwann cells, neuroglia, neurons, and mesodermal cells. In addition, PNSCs showed therapeutic potential by releasing the neurotrophic factors, including glial cell-line-derived neurotrophic factor, insulin-like growth factor, nerve growth factor, and neurotrophin-3. PNSC abilities were also enhanced by their development into spheroids which secreted neurotrophic factors several times more than non-spheroid PNSCs and expressed several types of extra cellular matrix. These features suggest that the potential for these PNSC spheroids can overcome their limitations. In an animal spinal cord injury (SCI) model, these PNSC spheroids induced functional recovery and neuronal regeneration. These PNSC spheroids also reduced the neuropathic pain which accompanies SCI after remyelination. These PNSC spheroids may represent a new therapeutic approach for patients suffering from SCI.  相似文献   
40.
Yoon  Yongsang  Yu  Jongmin  Jeon  Moongu 《Applied Intelligence》2022,52(3):2317-2331
Applied Intelligence - In skeleton-based action recognition, graph convolutional networks (GCNs), which model human body skeletons using graphical components such as nodes and connections, have...  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