全文获取类型
收费全文 | 608篇 |
免费 | 11篇 |
专业分类
电工技术 | 11篇 |
综合类 | 2篇 |
化学工业 | 125篇 |
金属工艺 | 10篇 |
机械仪表 | 29篇 |
建筑科学 | 18篇 |
能源动力 | 17篇 |
轻工业 | 39篇 |
水利工程 | 3篇 |
石油天然气 | 1篇 |
无线电 | 56篇 |
一般工业技术 | 94篇 |
冶金工业 | 153篇 |
原子能技术 | 6篇 |
自动化技术 | 55篇 |
出版年
2023年 | 3篇 |
2022年 | 4篇 |
2021年 | 10篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 2篇 |
2017年 | 6篇 |
2016年 | 3篇 |
2015年 | 10篇 |
2014年 | 11篇 |
2013年 | 24篇 |
2012年 | 26篇 |
2011年 | 21篇 |
2010年 | 23篇 |
2009年 | 31篇 |
2008年 | 27篇 |
2007年 | 30篇 |
2006年 | 26篇 |
2005年 | 14篇 |
2004年 | 18篇 |
2003年 | 19篇 |
2002年 | 17篇 |
2001年 | 15篇 |
2000年 | 15篇 |
1999年 | 18篇 |
1998年 | 41篇 |
1997年 | 27篇 |
1996年 | 28篇 |
1995年 | 9篇 |
1994年 | 19篇 |
1993年 | 13篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 12篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 8篇 |
1986年 | 6篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1983年 | 5篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 6篇 |
1978年 | 4篇 |
1977年 | 2篇 |
1976年 | 6篇 |
1975年 | 2篇 |
1973年 | 3篇 |
1964年 | 1篇 |
排序方式: 共有619条查询结果,搜索用时 15 毫秒
1.
2.
C Serveau L Juliano P Bernard T Moreau R Mayer F Gauthier 《Canadian Metallurgical Quarterly》1994,76(2):153-158
A discontinuous borate/formate buffer system is presented for horizontal polyacrylamide gel electrophoresis of DNA fragments. The resolution potential of the system could be altered by changing the total monomer concentration (5-9%T), the concentration of the crosslinker piperazine diacrylamide (2-5%CPDA), as well as the concentration of formate in the gel (40-120 mM), the leading ion of the buffer system. The separation of DNA fragments would be improved by increasing the migration distance from 22 to 28 cm. This discontinuous polyacrylamide gel electrophoresis system proved highly reproducible. 相似文献
3.
Bandura Albert; O'Leary Ann; Taylor C. Barr; Gauthier Janel; Gossard Denis 《Canadian Metallurgical Quarterly》1987,53(3):563
In this experiment, we tested for opioid and nonopioid mechanisms of pain control through cognitive means and the relation of opioid involvement to perceived coping efficacy. Subjects were taught cognitive methods of pain control, were administered a placebo, or received no intervention. Their pain tolerance was then measured at periodic intervals after they were administered either a saline solution or naloxone, an opiate antagonist that blocks the effects of endogenous opiates. Training in cognitive control strengthened perceived self-efficacy both to withstand and to reduce pain; placebo medication enhanced perceived efficacy to withstand pain but not reductive efficacy; and neither form of perceived self-efficacy changed without any intervention. Regardless of condition, the stronger the perceived self-efficacy to withstand pain, the longer subjects endured mounting pain stimulation. The findings provide evidence that attenuation of the impact of pain stimulation through cognitive control is mediated by both opioid and nonopioid mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
5.
6.
T. Caillot P. Glin J. Dailly G. Gauthier C. Cayron J. Laurencin 《Catalysis Today》2007,128(3-4):264-268
La0.8Sr0.2CrO3 based Ru catalysts were studied as potential new anodic materials for Solid Oxide Fuel Cells directly fed with methane and operating at intermediate temperature under water deficient conditions. Two kinds of materials very close in composition were obtained following two different preparation procedures. Catalyst samples were characterized by physicochemical methods (XRD, SEM, BET and Chemical Analysis) and studied in methane steam reforming under water deficient conditions. Carbon formation during catalytic testing was studied by temperature programmed oxidation (TPO). Both types of catalysts were found very active and resistant to carbon formation. The unusual oscillatory behavior of the catalytic activity observed for one type of catalyst was discussed. 相似文献
7.
Transmission line pulse (TLP) systems are mainly classified by their impedance, such as a 50- or 500-/spl Omega/ current source. A new TLP configuration allows switching between 50 and 500 /spl Omega/ by computer control to characterize a given part using both impedances. In addition, a four-needle Kelvin technique is introduced to TLP, which overcomes the measurement error from variations in contact resistance where the probe needles contact the wafer surface. 相似文献
8.
The mechanofusion process, a dry particle coating route, has been successfully applied to coat iron particles with alumina. The high-temperature oxidation resistance of Fe and coated Fe particles has been comparatively investigated in air in the temperature range 350°–900°C. The activation energy calculations demonstrate that, in the temperature range 350°–420°C, the oxidation mechanisms are the same for both particles. Scanning electron microscopy and energy-dispersive spectroscopy analyses show that oxidation products are mainly formed at the iron/alumina interface at low temperatures or at the alumina/gas interface at high temperatures. It is shown that, depending on the temperature range, two different oxidation mechanisms are predominant. 相似文献
9.
Bile acids as constituents for dental composites: in vitro cytotoxicity of (meth)acrylate and other ester derivatives of bile acids.
下载免费PDF全文
![点击此处可从《Journal of the Royal Society Interface》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Marc A Gauthier Pierre Simard Zhao Zhang X X Zhu 《Journal of the Royal Society Interface》2007,4(17):1145-1150
Methacrylic derivatives of bile acids have been synthesized for use as monomers in dental composites. Polymeric dental materials are known to leach cytotoxic unreacted monomers and degradation products. In this study, the in vitro cytotoxicity of bile acids and their derivatives towards 3T3 fibroblasts has been evaluated by colorimetric MTT assay and compared with that of the common dental monomers BisGMA, UDMA and TEGDMA. In general, the bile acids and their derivatives induced mitochondrial dysfunction at similar or higher concentrations than the commercial dental monomers. Certain monomers did not influence MTT response over their entire range of solubility. 相似文献
10.
Zakaria Chajar Michel Primet Hélène Praliaud Michèle Chevrier Catherine Gauthier Frédéric Mathis 《Catalysis Letters》1994,28(1):33-40
The role of nitrogen dioxide in the selective reduction of NO by propane over a Cu-MFI zeolite is investigated. NO2 and NO reductions were carried out under similar conditions of reaction. In the presence of oxygen, the reduction of NO by C3H8 does not differ significantly from that of NO2. In the absence of oxygen, the reduction of NO2 by propane occurs with a partial decomposition of the nitric dioxide molecule. Such a decomposition leads to the formation of oxygen, which is responsible for the increase in catalytic activity by comparison with the same reaction performed with NO. NO2 formed and released in the gas phase during the reduction of NO by propane in the presence of oxygen does not play a predominant role in the catalytic process. 相似文献