全文获取类型
收费全文 | 497篇 |
免费 | 14篇 |
国内免费 | 2篇 |
专业分类
电工技术 | 6篇 |
化学工业 | 126篇 |
金属工艺 | 5篇 |
机械仪表 | 10篇 |
建筑科学 | 18篇 |
能源动力 | 8篇 |
轻工业 | 46篇 |
水利工程 | 1篇 |
石油天然气 | 1篇 |
无线电 | 46篇 |
一般工业技术 | 71篇 |
冶金工业 | 121篇 |
原子能技术 | 7篇 |
自动化技术 | 47篇 |
出版年
2024年 | 2篇 |
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 9篇 |
2020年 | 7篇 |
2019年 | 6篇 |
2018年 | 13篇 |
2017年 | 9篇 |
2016年 | 14篇 |
2015年 | 11篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 19篇 |
2011年 | 22篇 |
2010年 | 17篇 |
2009年 | 12篇 |
2008年 | 16篇 |
2007年 | 13篇 |
2006年 | 10篇 |
2005年 | 15篇 |
2004年 | 8篇 |
2003年 | 8篇 |
2002年 | 11篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 39篇 |
1997年 | 23篇 |
1996年 | 24篇 |
1995年 | 16篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 6篇 |
1991年 | 8篇 |
1990年 | 9篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 6篇 |
1985年 | 11篇 |
1982年 | 3篇 |
1981年 | 5篇 |
1980年 | 6篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 6篇 |
1972年 | 2篇 |
1903年 | 2篇 |
1899年 | 1篇 |
排序方式: 共有513条查询结果,搜索用时 0 毫秒
41.
42.
43.
44.
This paper discusses the use of computer data structures in finite-element structural analysis programs. A number of data structure types that have been shown to be useful in such programs are introduced and described. A simple finite-element model is used to demonstrate how the given set of data structure types naturally lend themselves to developing software for the model. Different methods of implementing data structures in the context of a program are discussed. 相似文献
45.
Dipl.‐Ing. J. Knochen Prof. Dr.‐Ing. U. Kunz Prof. Dr.‐Ing. T. Turek Dipl.‐Chem. S. Ceylan Prof. Dr. A. Kirschning Dr.‐Ing. I. Kampen Dipl.‐Biotechnol. M. Vielkind Prof. Dr.‐Ing. A. Kwade Dipl.‐Ing. S. Arndt Prof. Dr.‐Ing. S. Scholl 《化学,工程师,技术》2010,82(10):1799-1806
A mobile plant for practical training was developed as part of the project μ‐Consortium to integrate micro process engineering into teaching. Lab experiments in the fields of mixing and homogenous reactions, heterogeneous reactions, heat transfer and particle synthesis were worked out to impart knowledge of different process‐engineering operations. 相似文献
46.
47.
The influence of process parameters on the H2O2 yield of gas diffusion electrodes (GDE) are investigated. The investigated GDEs consist of Vulcan XC72 carbon black and PTFE on gold-plated nickel wire cloth. An electrolysis cell is used to evaluate the influence of various process parameters, such as temperature, pH value, oxygen pressure and stoichiometric factor, electrolyte flow regime, current density and separator material at steady-state conditions. It is found that the investigated GDE enables current efficiencies greater than 90 % at up to 2 kA m−2, whereby lower electrolyte temperatures and higher pH values contribute to higher H2O2 yields above 90 % current efficiency. 相似文献
48.
Experimental charge and current measurements have recently been performed on an aircraft when it was exposed to the transient electromagnetic fi'eld of an electromagnetic pulse (EMP) simulator. These new data allow a test of the predictive capabilities of the three-dimensional finite-difference method for realistic aircraft simulator test problems. In the paper, the workings of the threedimensional finite-difference method and its required inputs and sensitivity to variations in the inputs are discussed in sufficient detail to enable others to employ the method. A companion paper compares the experimental measurements to predictions for a large variety of measurement locations. Agreement is shown to be good for all major response measurements and satisfactory for a number of other measurements. 相似文献
49.
Beifang Yang Airton Martin M. J. G. Lee J. M. Perz 《Journal of Superconductivity and Novel Magnetism》1996,9(2):161-165
Sintered ceramic samples of Bi2Sr2?x Ba x CaCu2Oy with nominal barium fraction 0≤x≤0.3 have been prepared by the solid-state reaction method. WDS studies verified that barium enters the superconducting phase. For slowly cooled samples, the midpointT c of the superconducting transition is significantly increased by barium doping, whereas for quenched samplesT c is little affected. The increase ofT c with increasing barium fraction is consistent with a decrease in the hole concentration in the superconducting layers. 相似文献
50.