全文获取类型
收费全文 | 2258篇 |
免费 | 96篇 |
国内免费 | 20篇 |
专业分类
电工技术 | 29篇 |
综合类 | 4篇 |
化学工业 | 459篇 |
金属工艺 | 59篇 |
机械仪表 | 74篇 |
建筑科学 | 47篇 |
矿业工程 | 2篇 |
能源动力 | 135篇 |
轻工业 | 129篇 |
水利工程 | 14篇 |
石油天然气 | 8篇 |
无线电 | 306篇 |
一般工业技术 | 544篇 |
冶金工业 | 193篇 |
原子能技术 | 21篇 |
自动化技术 | 350篇 |
出版年
2023年 | 50篇 |
2022年 | 93篇 |
2021年 | 126篇 |
2020年 | 109篇 |
2019年 | 99篇 |
2018年 | 140篇 |
2017年 | 99篇 |
2016年 | 101篇 |
2015年 | 68篇 |
2014年 | 86篇 |
2013年 | 168篇 |
2012年 | 100篇 |
2011年 | 132篇 |
2010年 | 108篇 |
2009年 | 61篇 |
2008年 | 75篇 |
2007年 | 85篇 |
2006年 | 52篇 |
2005年 | 45篇 |
2004年 | 32篇 |
2003年 | 24篇 |
2002年 | 33篇 |
2001年 | 35篇 |
2000年 | 13篇 |
1999年 | 23篇 |
1998年 | 41篇 |
1997年 | 46篇 |
1996年 | 32篇 |
1995年 | 17篇 |
1994年 | 20篇 |
1993年 | 21篇 |
1992年 | 15篇 |
1991年 | 20篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1988年 | 12篇 |
1987年 | 13篇 |
1986年 | 13篇 |
1985年 | 9篇 |
1984年 | 16篇 |
1983年 | 18篇 |
1982年 | 7篇 |
1981年 | 12篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1978年 | 9篇 |
1977年 | 12篇 |
1976年 | 17篇 |
1973年 | 5篇 |
1966年 | 3篇 |
排序方式: 共有2374条查询结果,搜索用时 31 毫秒
1.
Wireless Personal Communications - A Delay Tolerant Network (DTN) is a network capable of handling long delays and data loss efficiently in various challenged scenarios and environments. Owing to... 相似文献
2.
Wireless Personal Communications - The recent pandemic has demanded a strong and smart healthcare system which can monitor the patients efficiently and handle the situation that arises from the... 相似文献
3.
Wireless Personal Communications - Authentication is a term very important for data communication security. We see many frauds due to authentication failure. The problem manifolds when... 相似文献
4.
Ondrej Hanzel Meinam Annebushan Singh Deepak Marla Richard Sedlák Pavol Šajgalík 《Journal of the European Ceramic Society》2019,39(8):2626-2633
SiC based composites filled with graphene nano-platelets (GNPs) or graphene oxide (GO) prepared by rapid hot-pressing exhibit sufficient electrical conductivity for their machinability by wire electro-discharge machining (WEDM). Composites microstructure anisotropy caused by graphene alignment as a consequence of rapid hot pressing was confirmed by measuring of electrical conductivity and thermal diffusivity. Electrical conductivity increased significantly with increased weight fraction of graphene in both measured directions. Highest value of 2031 S/m was obtained for composites with 15 wt. % of GNPs in parallel direction and only 1246 S/m in perpendicular direction to aligned GNPs. Thermal diffusivity is 63.3 mm2/s in parallel and only 23.3 mm2/s in perpendicular direction. The increase of the electrical conductivity has resulted in successful WEDM. The MRR was almost doubled when the filler concentration increased from 5 wt. % GNPs/GO to 15 wt. % GNPs. At the same time, the surface roughness decreased. 相似文献
5.
Avnish Verma Ayse Orme Merve Vytautas Remekevi
ius Pola Sobiecka Luke Taylor Scott Lawton Ben P Jones Elena Polycarpou Jason Bennett Brian Rooney 《International journal of molecular sciences》2021,22(5)
Cocaine is one of the most widely abused illicit drugs worldwide and has long been recognised as an agent of cardiac dysfunction in numerous cases of drug overdose. Cocaine has previously been shown to up-regulate cytoskeletal rearrangements and morphological changes in numerous tissues; however, previous literature observes such changes primarily in clinical case reports and addiction studies. An investigation into the fundamental cytoskeletal parameters of migration, adhesion and proliferation were studied to determine the cytoskeletal and cytotoxic basis of cocaine in cardiac cells. Treatment of cardiac myocytes with cocaine increased cell migration and adhesion (p < 0.05), with no effect on cell proliferation, except with higher doses eliciting (1–10 μg/mL) its diminution and increase in cell death. Cocaine downregulated phosphorylation of cofilin, decreased expression of adhesion modulators (integrin-β3) and increased expression of ezirin within three hours of 1 μg/mL treatments. These functional responses were associated with changes in cellular morphology, including alterations in membrane stability and a stellate-like phenotype with less compaction between cells. Higher dose treatments of cocaine (5–10 μg/mL) were associated with significant cardiomyocyte cell death (p < 0.05) and loss of cellular architecture. These results highlight the importance of cocaine in mediating cardiomyocyte function and cytotoxicity associated with the possible loss of intercellular contacts required to maintain normal cell viability, with implications for cardiotoxicity relating to hypertrophy and fibrogenesis. 相似文献
6.
Yang Chao-Tung Chen Shuo-Tsung Liu Jung-Chun Chan Yu-Wei Chen Chien-Chih Verma Vinod Kumar 《The Journal of supercomputing》2019,75(8):4408-4429
The Journal of Supercomputing - In the last decade, cloud computing has brought enormous changes to people’s lives. Cloud computing gives a client-driven computational model. In this case,... 相似文献
7.
Silicon - The original version of this paper was unfortunately published with an error in the order of authors and their corresponding affiliations. The correct data is shown above. 相似文献
8.
Silicon - Silicon carbide piezoresistive pressure sensor is more suitable for harsh environment due to its wide bandgap, corrosion tolerance, excellent chemical inertness, high Young’s... 相似文献
9.
10.
Multimedia Tools and Applications - In this paper, we propose a novel interpolation and a new reversible data hiding scheme for upscaling the original image and hiding secret data into the... 相似文献