全文获取类型
收费全文 | 347039篇 |
免费 | 3541篇 |
国内免费 | 797篇 |
专业分类
电工技术 | 6322篇 |
综合类 | 238篇 |
化学工业 | 50094篇 |
金属工艺 | 15835篇 |
机械仪表 | 10692篇 |
建筑科学 | 6794篇 |
矿业工程 | 2491篇 |
能源动力 | 7065篇 |
轻工业 | 22104篇 |
水利工程 | 4227篇 |
石油天然气 | 10503篇 |
武器工业 | 19篇 |
无线电 | 39778篇 |
一般工业技术 | 71900篇 |
冶金工业 | 69415篇 |
原子能技术 | 9834篇 |
自动化技术 | 24066篇 |
出版年
2021年 | 2658篇 |
2019年 | 2687篇 |
2018年 | 4797篇 |
2017年 | 4869篇 |
2016年 | 5191篇 |
2015年 | 3013篇 |
2014年 | 5273篇 |
2013年 | 13652篇 |
2012年 | 8273篇 |
2011年 | 10903篇 |
2010年 | 8868篇 |
2009年 | 10117篇 |
2008年 | 10547篇 |
2007年 | 10490篇 |
2006年 | 9309篇 |
2005年 | 8672篇 |
2004年 | 8462篇 |
2003年 | 8186篇 |
2002年 | 7941篇 |
2001年 | 8346篇 |
2000年 | 7852篇 |
1999年 | 8241篇 |
1998年 | 21441篇 |
1997年 | 14723篇 |
1996年 | 11189篇 |
1995年 | 8308篇 |
1994年 | 7237篇 |
1993年 | 7351篇 |
1992年 | 5354篇 |
1991年 | 5253篇 |
1990年 | 5305篇 |
1989年 | 5075篇 |
1988年 | 4819篇 |
1987年 | 4178篇 |
1986年 | 4288篇 |
1985年 | 4619篇 |
1984年 | 4250篇 |
1983年 | 3958篇 |
1982年 | 3680篇 |
1981年 | 3979篇 |
1980年 | 3646篇 |
1979年 | 3734篇 |
1978年 | 3845篇 |
1977年 | 4199篇 |
1976年 | 5514篇 |
1975年 | 3474篇 |
1974年 | 3458篇 |
1973年 | 3462篇 |
1972年 | 3081篇 |
1971年 | 2699篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Kozhitov L. V. Kiselev B. G. Raykova T. B. Popkova A. V. Kostishin V. G. Muratov D. G. Yakushko E. V. Kosushkin V. G. Bebenin V. G. 《Russian Microelectronics》2019,48(8):599-612
Russian Microelectronics - The recently developed nanomaterials and their production technologies as intellectual property objects (IPOs) are considered. The role of the informational-analytical... 相似文献
112.
Zinov’eva I. V. Fedorov A. Ya. Milevskii N. A. Zakhodyaeva Yu. A. Voshkin A. A. 《Theoretical Foundations of Chemical Engineering》2021,55(4):663-670
Theoretical Foundations of Chemical Engineering - A choline chloride–sulfosalicylic acid deep eutectic solvent (DES) is proposed for dissolving the oxides Co(II), Cu(II), Zn(II), Fe(III),... 相似文献
113.
Chertkov Yu. B. Anikin M. N. Lebedev I. I. Naimushin A. G. Smol’nikov N. V. 《Atomic Energy》2021,131(1):42-45
Atomic Energy - The results of calculations and experimental determination of the neutronics characteristics of the IRT-T research reactor are presented. The IRT-T reactor is a pool reactor with... 相似文献
114.
Geetha R. Madhusudhan V. Padmavathy T. Lallithasree A. 《Wireless Personal Communications》2019,108(3):1957-1976
Wireless Personal Communications - The majority of security systems for wireless sensor networks are based on symmetric encryption. The main open issue for these approaches concerns the... 相似文献
115.
High Temperature - Experimental findings suggest that a strongly ionized, arc He plasma of atmospheric pressure does not exist in the state of the local thermodynamic equilibrium (LTE) expected for... 相似文献
116.
Russian Engineering Research - Improvement in the wear resistance of plunger-pump rods is considered. Hardening by high-frequency current is proposed. 相似文献
117.
E. G. Kulapina N. M. Makarova O. I. Kulapina I. A. Utc V. V. Baraguzina 《Petroleum Chemistry》2015,55(10):892-900
Potentiometric sensors with plasticized poly(vinyl chloride) membranes based on β-lactam–tetraalkylammonium ion associates sensitive to penicillin antibiotics are proposed. The physicochemical characteristics (solubility product constants and dissociation constants) of active membrane components and the electrode, transport, and selective properties of the membranes of liquidand solid-contact sensors have been studied. The quantitative characteristics of membrane transport (penetrability, ion flux, and transport rate) have been evaluated. The main charge carriers in the membranes and at the membrane/solution interface have been determined from the membrane transport characteristics. The potentiometric sensors are shown to be applicable to the determination of penicillin antibiotics in biological fluids (blood serum and oral fluid) from patients with urinary tract infection. 相似文献
118.
V. N. Oparin V. I. Vostrikov O. M. Usol’tseva P. A. Tsoi V. N. Semenov 《Journal of Mining Science》2015,51(3):624-633
The authors have developed a procedure and a test bench for studying evolution of various nature physical fields in modeling geomedium fracture by fluids. The test bench performs synchronous recording of macro- and micro-deformation, heat and acoustic emission induced in physical models of geomedium under loading to discontinuity. The experimental procedure has been trialed. The analysis of the synchronized test data allows a conclusion on the existence of time–space relationship between different nature physical fields induced during failure of solids. 相似文献
119.
120.