全文获取类型
收费全文 | 1250篇 |
免费 | 7篇 |
国内免费 | 1篇 |
专业分类
综合类 | 3篇 |
化学工业 | 15篇 |
金属工艺 | 3篇 |
机械仪表 | 7篇 |
能源动力 | 2篇 |
轻工业 | 12篇 |
石油天然气 | 1篇 |
无线电 | 10篇 |
一般工业技术 | 24篇 |
冶金工业 | 1158篇 |
原子能技术 | 1篇 |
自动化技术 | 22篇 |
出版年
2023年 | 3篇 |
2022年 | 1篇 |
2021年 | 7篇 |
2020年 | 6篇 |
2019年 | 5篇 |
2018年 | 12篇 |
2017年 | 3篇 |
2016年 | 6篇 |
2015年 | 3篇 |
2014年 | 4篇 |
2013年 | 17篇 |
2012年 | 5篇 |
2011年 | 3篇 |
2010年 | 1篇 |
2009年 | 4篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 5篇 |
2005年 | 1篇 |
2003年 | 3篇 |
2001年 | 2篇 |
2000年 | 1篇 |
1999年 | 29篇 |
1998年 | 374篇 |
1997年 | 186篇 |
1996年 | 125篇 |
1995年 | 77篇 |
1994年 | 65篇 |
1993年 | 68篇 |
1992年 | 6篇 |
1991年 | 13篇 |
1990年 | 15篇 |
1989年 | 18篇 |
1988年 | 18篇 |
1987年 | 4篇 |
1986年 | 17篇 |
1985年 | 9篇 |
1983年 | 2篇 |
1982年 | 6篇 |
1981年 | 8篇 |
1980年 | 13篇 |
1978年 | 4篇 |
1977年 | 21篇 |
1976年 | 78篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1966年 | 1篇 |
1965年 | 1篇 |
1960年 | 1篇 |
1955年 | 1篇 |
排序方式: 共有1258条查询结果,搜索用时 15 毫秒
61.
Of 30 bile acids tested, none was mutagenic in the Salmonella-mammalian-microsome test with indicator strains G46, TA1530, TA1535, TA1536, TA1537, TA1538, TA98, or TA100. However, when lithocholic acid or one of its conjugates was tested with suboptimal amounts of 2-aminoanthracene and phenobarbital-stimulated rat liver homogenate, enhancement and co-mutagenesis were observed if TA1538 was the indicator strain. 相似文献
62.
63.
64.
AC Egberts AW Lenderink FH de Koning HG Leufkens 《Canadian Metallurgical Quarterly》1997,17(3):149-155
OBJECTIVE: Trifluoromethane and CO are produced simultaneously during the breakdown of isoflurane and desflurane by dry CO2 absorbents. Trifluoromethane interferes with anesthetic agent monitoring, and the interference can be used as a marker to indicate anesthetic breakdown with CO production. This study tests representative types of gas monitors to determine their ability to provide a clinically useful warning of CO production in circle breathing systems. METHODS: Isoflurane and desflurane were reacted with dry Baralyme at 45 degrees C. Standardized samples of breakdown products were created from mixtures of reacted and unreacted gases to simulate the partial degrees of reaction which might result during clinical episodes of anesthetic breakdown using 1% or 2% isoflurane and 6% or 12% desflurane. These mixtures were measured by the monitors tested, and the indication of the wrong agent or a mixture of agents due to the presence of trifluoromethane was recorded and related to the CO concentration in the gas mixtures. RESULTS: When presented with trifluoromethane from anesthetic breakdown, monochromatic infrared monitors displayed inappropriately large amounts of isoflurane or desflurane. Agent identifying infrared and Raman scattering monitors varied in their sensitivity to trifluoromethane. Mass spectrometers measuring enflurane at mass to charge = 69 were most sensitive to trifluoromethane. CONCLUSION: Monochromatic infrared monitors were unable to indicate anesthetic breakdown via interference by trifluoromethane, but did indicate falsely elevated anesthetic concentrations. Agent identifying infrared and Raman monitors provided warning of desflurane breakdown via the interference of trifluoromethane by displaying the wrong agent or mixed agents, but may not be sensitive enough to warn of isoflurane breakdown Some mass spectrometers provided the most sensitive warnings to anesthetic breakdown via trifluoromethane, but additional data processing by some patients monitor units reduced their overall effectiveness. 相似文献
65.
66.
67.
68.
STANISŁAW OSOWSKI 《International Journal of Electronics》2013,100(3):591-598
The analysis and synthesis are presented of a non-linear ladder network with diodes incorporated in the series branches. An explicit form of solution is proposed and then applied to the synthesis of piecewise-linear characteristics. An illustrative example is given. 相似文献
69.
AW AD R. MANSOUR 《Chemical Engineering Communications》2013,200(1):133-135
Mixing in co-rotating sinusoidal cavity flows is studied with period, T, and phase shift, a, as parameters. Notice that the main obstacle to uniform mixing is the existence of stable :ower periodic orbits, mixing windows, where uniform mixing takes place, are found in the T— a space u:iing bifurcation analysis. The main advantage of this method is a great saving of the computation time. 相似文献
70.