全文获取类型
收费全文 | 4147篇 |
免费 | 305篇 |
国内免费 | 2篇 |
学科分类
工业技术 | 4454篇 |
出版年
2024年 | 7篇 |
2023年 | 44篇 |
2022年 | 53篇 |
2021年 | 175篇 |
2020年 | 124篇 |
2019年 | 147篇 |
2018年 | 186篇 |
2017年 | 176篇 |
2016年 | 179篇 |
2015年 | 154篇 |
2014年 | 193篇 |
2013年 | 339篇 |
2012年 | 329篇 |
2011年 | 361篇 |
2010年 | 283篇 |
2009年 | 240篇 |
2008年 | 253篇 |
2007年 | 211篇 |
2006年 | 163篇 |
2005年 | 147篇 |
2004年 | 105篇 |
2003年 | 93篇 |
2002年 | 92篇 |
2001年 | 41篇 |
2000年 | 29篇 |
1999年 | 28篇 |
1998年 | 35篇 |
1997年 | 24篇 |
1996年 | 17篇 |
1995年 | 42篇 |
1994年 | 18篇 |
1993年 | 17篇 |
1992年 | 12篇 |
1991年 | 17篇 |
1990年 | 13篇 |
1989年 | 13篇 |
1988年 | 9篇 |
1987年 | 6篇 |
1986年 | 5篇 |
1985年 | 7篇 |
1984年 | 11篇 |
1983年 | 8篇 |
1981年 | 3篇 |
1980年 | 3篇 |
1979年 | 7篇 |
1978年 | 4篇 |
1977年 | 5篇 |
1976年 | 4篇 |
1975年 | 8篇 |
1974年 | 3篇 |
排序方式: 共有4454条查询结果,搜索用时 15 毫秒
1.
A low pressure impactor is used to measure triboelectric charging behavior of metallic nanoparticles. Ag nanoparticles, produced by spark discharge, were impacted onto Pt sputtered targets. The influence of the impaction angle and impaction velocity on the triboelectric charging was investigated. While for perpendicular impaction the charge transfer behavior of previous work was confirmed, the oblique impaction revealed new phenomena. Additional charge transfer was observable, which increases with obliqueness. The possibility of mass transfer between particle and target due to the high-energy collisions was also investigated. SEM characterization and Auger spectroscopy indicate mass transfer from the particle to the target surface. 相似文献
2.
The combined effect of resistance spot welding and precipitation hardening on the localised corrosion of A286 superalloy is studied. The specimens tested by double loop electrochemical potentiokinetic reactivation were welded in the solution treated condition, and then subjected to different precipitation hardening treatments. For both base metal and weld nugget, the maximum localised corrosion is reached when η phase is clearly observable. The fact that the localised corrosion resistance of weld nugget is different from that shown by base metal may be explained by the segregation of Ni and Ti towards the interdendritic region of weld nugget (studied by using scanning electron microscope/energy dispersive X-ray analysis). 相似文献
3.
Lipase production by solid‐state fermentation of olive pomace in tray‐type and pressurized bioreactors 下载免费PDF全文
4.
Carmen J. Pastor-Maldonado Juan M. Surez-Rivero Suleva Povea-Cabello Mnica lvarez-Crdoba Irene Villaln-García Manuel Munuera-Cabeza Alejandra Surez-Carrillo Marta Talavern-Rey Jos A. Snchez-Alczar 《International journal of molecular sciences》2020,21(22)
The aim of this review is to shed light over the most recent advances in Coenzyme Q10 (CoQ10) applications as well as to provide detailed information about the functions of this versatile molecule, which have proven to be of great interest in the medical field. Traditionally, CoQ10 clinical use was based on its antioxidant properties; however, a wide range of highly interesting alternative functions have recently been discovered. In this line, CoQ10 has shown pain-alleviating properties in fibromyalgia patients, a membrane-stabilizing function, immune system enhancing ability, or a fundamental role for insulin sensitivity, apart from potentially beneficial properties for familial hypercholesterolemia patients. In brief, it shows a remarkable amount of functions in addition to those yet to be discovered. Despite its multiple therapeutic applications, CoQ10 is not commonly prescribed as a drug because of its low oral bioavailability, which compromises its efficacy. Hence, several formulations have been developed to face such inconvenience. These were initially designed as lipid nanoparticles for CoQ10 encapsulation and distribution through biological membranes and eventually evolved towards chemical modifications of the molecule to decrease its hydrophobicity. Some of the most promising formulations will also be discussed in this review. 相似文献
5.
6.
7.
Marcel Loewert Julian Hoffmann Paolo Piermartini Manuel Selinsek Roland Dittmeyer Peter Pfeifer 《化学工程与技术》2019,42(10):2202-2214
Current projects focusing on the energy transition in traffic will rely on a high‐level technology mix for their commissioning. One of those technologies is the Fischer‐Tropsch synthesis (FTS) that converts synthesis gas into hydrocarbons of different chain lengths. A microstructured packed‐bed reactor for low‐temperature FTS is tested towards its versatility for biomass‐based syngas with a high inert gas dilution. Investigations include overall productivity, conversion, and product selectivity. A 60‐times larger pilot‐scale reactor is further tested. Evaporation cooling is introduced which allows to increase the available energy extraction from the system. From that scale on, an autothermal operation at elevated conversion levels is applicable. 相似文献
8.
Improvement of 19F MR image uniformity in a mouse model of cellular therapy using inductive coupling
Park Bu S. Ma Ge Koch William T. Rajan Sunder S. Mastromanolis Manuel Lam Johnny Sung Kyung McCright Brent 《Magma (New York, N.Y.)》2019,32(1):15-23
Magnetic Resonance Materials in Physics, Biology and Medicine - Improve 19F magnetic resonance imaging uniformity of perfluorocarbon (PFC)-labeled cells by using a secondary inductive resonator... 相似文献
9.
Dolz Manuel F. Alventosa Fran J. Alonso-Jordá Pedro Vidal Antonio M. 《The Journal of supercomputing》2019,75(3):1470-1482
The Journal of Supercomputing - There exist problems in the field of digital signal processing, such as filtering of acoustic signals that require processing a large amount of data in real time.... 相似文献