首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   86篇
  免费   0篇
电工技术   1篇
化学工业   3篇
能源动力   3篇
轻工业   72篇
无线电   1篇
一般工业技术   4篇
冶金工业   2篇
  2009年   1篇
  2008年   2篇
  2007年   1篇
  2006年   3篇
  1991年   1篇
  1987年   1篇
  1984年   1篇
  1948年   2篇
  1944年   4篇
  1943年   16篇
  1942年   13篇
  1941年   11篇
  1940年   7篇
  1939年   6篇
  1938年   5篇
  1937年   3篇
  1934年   1篇
  1933年   2篇
  1932年   2篇
  1931年   2篇
  1929年   1篇
  1917年   1篇
排序方式: 共有86条查询结果,搜索用时 203 毫秒
31.
Miniaturized solid oxide fuel cells are fabricated on a photostructurable glass ceramic substrate (Foturan) by thin film and micromachining techniques. The anode is a sputtered platinum film and the cathode is made of a spray pyrolysis (SP)‐deposited lanthanum strontium cobalt iron oxide (LSCF), a sputtered platinum film and platinum paste. A single‐layer of yttria‐stabilized zirconia (YSZ) made by pulsed laser deposition (PLD) and a bilayer of PLD–YSZ and SP–YSZ are used as electrolytes. The total thickness of all layers is less than 1 µm and the cell is a free‐standing membrane with a diameter up to 200 µm. The electrolyte resistance and the sum of polarization resistances of the anode and cathode are measured between 400 and 600 °C by impedance spectroscopy and direct current (DC) techniques. The contribution of the electrolyte resistance to the total cell resistance is negligible for all cells. The area‐specific polarization resistance of the electrodes decreases for different cathode materials in the order of Pt paste > sputtered Pt > LSCF. The open circuit voltages (OCVs) of the single‐layer electrolyte cells ranges from 0.91 to 0.56 V at 550 °C. No electronic leakage in the PLD–YSZ electrolyte is found by in‐plane and cross‐plane electrical conductivity measurements and the low OCV is attributed to gas leakage through pinholes in the columnar microstructure of the electrolyte. By using a bilayer electrolyte of PLD–YSZ and SP–YSZ, an OCV of 1.06 V is obtained and the maximum power density reaches 152 mW cm−2 at 550 °C.  相似文献   
32.
33.
34.
35.
36.
37.
38.
39.
Summary Ethanol, isopropanol, isobutanol, ethylene dichloride, trichloroethylene, carbon tetrachloride, and hexane (b.p. range 30° to 60°C.) were used as solvents for the extraction of soybean oil and the comparative effect of the solvent on the color and other properties of the oil, meal, and isolated protein was measured. Ethanol extraction gave the best results with respect to the color of oil, meal, and protein, and it also served as a debittering agent for the soybean meal. One of the laboratories of the Bureau of Agricultural and Industrial Chemistry, Agricultural Research Administration, U. S. Department of Agriculture.  相似文献   
40.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号