摘要
介绍一种用于轻轨铸钢支座定位板零件的落料和整修加工工艺及模具设计。冲裁加工是一种广泛应用于板形零件的加工手段,它具有高效、少屑、互换性好等特点,尤其对于边界轮廓特异的板形类零件的加工更具明显优势。
Hydrocarbon gases such as methane, ethane, ethylene and acetylene are effective characteristic gases in transformer faults, while the metallic oxide semiconductor gas sensor can be applied in online monitoring of dissolved gases in the transformer oil. Based on the self-made metallic oxide semiconductor gas sensor, this essay introduces the tests on the characteristics of the gas detections of methane, ethane, ethylene and acetylene in the low concentra- tion range of 1 micro liter per liter to 20 micro liters per liter and explores its response mechanism. Besides, this es- say also introduces the calculations and analyses of the energy levels of the molecular orbits as well as the qualitative analysis of the selective mechanism of the sensor. The results indicate that under the same working voltage, the sen- sor shows a better selectivity to those four hydrocarbon gases when they are at a low level of concentration. Moreo- ver, the differences among the energy levels of the molecular orbits of the gases together with the differences in the optimum absorption temperatures of gas-sensitive materials are qualitative factors of the selectivity of the gas-sensi- tive sensor.
出处
《重庆电力高等专科学校学报》
2014年第2期58-62,共5页
Journal of Chongqing Electric Power College
关键词
冲裁
厚板
落料
整修
hydrocarbon gases
metallic oxide sensor
sensitivity
repeatability
linearity
