全文获取类型
收费全文 | 1609223篇 |
免费 | 36110篇 |
国内免费 | 11605篇 |
专业分类
电工技术 | 40398篇 |
技术理论 | 16篇 |
综合类 | 13720篇 |
化学工业 | 273718篇 |
金属工艺 | 69856篇 |
机械仪表 | 49171篇 |
建筑科学 | 52601篇 |
矿业工程 | 14817篇 |
能源动力 | 52710篇 |
轻工业 | 120448篇 |
水利工程 | 17093篇 |
石油天然气 | 43069篇 |
武器工业 | 1058篇 |
无线电 | 208799篇 |
一般工业技术 | 295701篇 |
冶金工业 | 185466篇 |
原子能技术 | 35186篇 |
自动化技术 | 183111篇 |
出版年
2021年 | 18560篇 |
2020年 | 14847篇 |
2019年 | 17106篇 |
2018年 | 18603篇 |
2017年 | 18438篇 |
2016年 | 24185篇 |
2015年 | 21477篇 |
2014年 | 33773篇 |
2013年 | 94283篇 |
2012年 | 43185篇 |
2011年 | 56526篇 |
2010年 | 49676篇 |
2009年 | 57707篇 |
2008年 | 52197篇 |
2007年 | 49223篇 |
2006年 | 51809篇 |
2005年 | 45662篇 |
2004年 | 45479篇 |
2003年 | 44342篇 |
2002年 | 41327篇 |
2001年 | 38179篇 |
2000年 | 36028篇 |
1999年 | 36371篇 |
1998年 | 50772篇 |
1997年 | 42645篇 |
1996年 | 36977篇 |
1995年 | 33073篇 |
1994年 | 30583篇 |
1993年 | 30152篇 |
1992年 | 26720篇 |
1991年 | 23727篇 |
1990年 | 23974篇 |
1989年 | 22823篇 |
1988年 | 21278篇 |
1987年 | 19466篇 |
1986年 | 18871篇 |
1985年 | 22160篇 |
1984年 | 22266篇 |
1983年 | 20123篇 |
1982年 | 19138篇 |
1981年 | 19248篇 |
1980年 | 17815篇 |
1979年 | 18383篇 |
1978年 | 17652篇 |
1977年 | 17472篇 |
1976年 | 18825篇 |
1975年 | 15859篇 |
1974年 | 15410篇 |
1973年 | 15454篇 |
1972年 | 13027篇 |
排序方式: 共有10000条查询结果,搜索用时 176 毫秒
71.
Jakeria Mohd Rafiuddin Toh Rou Jun Chen Xiao-Bo Cole Ivan S. 《Journal of Applied Electrochemistry》2022,52(6):1021-1044
Journal of Applied Electrochemistry - Organic corrosion inhibitors have become competent alternatives to hazardous chrome conversion coatings due to their rapid adsorption over metal surfaces in... 相似文献
72.
Rukomoynikov A. A. Yuminov I. P. Khamitov A. I. Garifullin I. Sh. Agliullin Ya. F. 《Russian Engineering Research》2022,42(9):916-919
Russian Engineering Research - Systems are considered for the dehydration of petroleum so as to separate water–petroleum emulsions. In particular, the low-temperature microwave (UHF)... 相似文献
74.
Wireless Personal Communications - Nowadays, Wireless Sensor Networks (WSNs) is enhancing for different applications. Simultaneously, energy consumption for processing the tasks in most of the... 相似文献
75.
76.
Zhang Qi Wang Yujing Zhang Xueling Song Jun Li Yinlei Wu Xuehong Yuan Kunjie 《Journal of Materials Science》2022,57(14):7208-7224
Journal of Materials Science - Form-stable composite phase change materials (C-PCMs) prepared by microencapsulation method and porous matrix adsorption method need for compression molding after... 相似文献
77.
Volkov K. N. Emelyanov V. N. Karpenko A. G. 《Journal of Engineering Physics and Thermophysics》2022,95(1):80-89
Journal of Engineering Physics and Thermophysics - A simulation of the vibroacoustic processes proceeding in a long pipe with an obstacle in the form of a circular cylinder, in which a fluid flows,... 相似文献
78.
Radiochemistry - The sorption extraction of Pu and Am from nitric acid simulation solutions were studied on a solid extractant (TVEX) AXIONIT MND 40T in a static mode. It is shown that the... 相似文献
79.
Li Cao Ying Wu Wenwen Li Zengmiao Zhang Yaping Niu Chenchen Li Shaobin Gu 《Journal of food science》2022,87(7):3248-3259
This study aimed to determine the main bioactive components of Cornus officinalis vinegar (COV) and assess the effects of COV on the body weight (BW) and hepatic steatosis in a nonalcoholic fatty liver disease (NAFLD) mouse model. Seven-week-old KM female mice were divided into five treatment groups: (1) Normal control (NC) group, (2) high fat diet (HFD) group, (3) low concentration treatment group (3.5% COV), (4) medium concentration treatment group (5.0% COV), and (5) high concentration treatment group (6.5% COV). Mice in the NC group were fed with a normal chow diet, and those in the other four groups were fed with a HFD known for causing obesity for 10 weeks. Then, mice in the three COV treatment groups were orally administered with COV once a day for 6 weeks. Results showed that the contents of loganin and morroniside in COV reached 16.82 and 51.17 µg/ml, respectively, and COV also contained multiple organic acids. COV significantly reduced BW, abdominal fat weight, liver weight, and the levels of glucose, triglyceride, and low-density lipoprotein cholesterol of serum and increased the levels of high-density lipoprotein cholesterol of serum (p < 0.05). COV also improved the liver function and anti-oxidant activity of liver (p < 0.05). COV treatments increased the interleukin-10 expression and reduced the tumor necrosis factor-α expression in the liver tissue of NAFLD mice (p < 0.05). Histopathological observation revealed that COV suppressed hepatic lipid accumulation and steatosis. The results suggest that COV may contribute to the alleviation of NAFLD and obesity. 相似文献
80.