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81.
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83.
微机在应变测量中的应用,采用上位机和下位机组合方式.上位机为一台IBM-PC/XT微机,用于对数据进行后处理.下位机以Z80-CPU为控制器,由传感器、转换器、接口及外设等组成数据采集器,实施对应变、压力和位移等参数的采集、显示和打印(即数据的预处理).上位机和下位机之间的数据传输,采用串行的方式,通过RS-232接口完成.本文主要以应变的采集处理为例,介绍系统功能、硬件配置及软件设计. 相似文献
84.
本文主要介绍陶瓷传感器在微型化及集成化方面的进展;指出了集成化多功能传感器存在的技术问题及未来发展趋势。 相似文献
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86.
补偿元件对载体催化元件输出特性的影响 总被引:2,自引:1,他引:1
阐述了矿井瓦斯传感器-载体催化元件在应用中,补偿元件发挥的作用和工作原理,着重分析了补偿元件对载体催化元件输出特性的影响,探讨了提高线性补偿效果的方法。 相似文献
87.
An original procedure has been established for estimating the overall volumetric mass transfer coefficient using the oxygen concentration curves resulting from the usual gassing-in and gassing-out method. This procedure was applied to experimental data obtained in a small scale bubble column using both tap water and a coalescence-inhibiting liquid mixture that represents the coalescence behavior of biological media. It is based on the analysis of the characteristics times of the system, including those of the hydrodynamics of the two phases, the sensor dynamics and the system inertia when the gas composition is modified. A numerical procedure was developed to estimate the characteristic time of the system inertia ti, using the assumption that this inertia is nearly independent of superficial gas velocity UG. The calculations confirmed that the optimized ti value was nearly independent of UG and of the coalescence behavior of the liquid phase. Additionally, the resulting KLaL values for tap water were closer to the correlation of Shah et al. [1982. Design parameters estimations for bubble column reactors. A.I.Ch.E. Journal 28, 353-379] than those of other conventional models. Finally, the original procedure was also reported to reduce significantly the square sum deviation between the predicted and the measured oxygen response curves. 相似文献
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89.
A simple measuring procedure for low concentrations of H2 and H2S (at the level of ppm fractions) above the surface of water by using sensitive gas analyzers is suggested. The procedure is easily accomplished in conditions outside the laboratory (under field conditions). 相似文献
90.
A.K. PrasadP.I. Gouma D.J. Kubinski J.H. VisserR.E. Soltis P.J. Schmitz 《Thin solid films》2003,436(1):46-51
We report the gas-sensing properties of ion-beam sputter deposited MoO3 thin-films. The change in the DC conductivity was measured in dry N2 with 10% O2 in the presence of up to 490 ppm of NH3, NO, NO2, C3H6, CO and H2. At ∼440 °C the film was found to be very sensitive to NH3, with 490 ppm increasing the conductivity by approximately a factor of 70. This was approximately 17 times greater than the response to the other gases. The NH3 response was strongly affected by the accompanying levels of O2, NO2 and H2O. For example, changing the accompanying O2 levels from 1% to 20% decreased the NH3 response by approximately a factor of 20. Similarly, the presence of 100 ppm NO2 (in 10% O2) decreased the NH3 response by approximately a factor of three, and 1% water vapor decreased it by more than a factor of two. The NH3 response, however, was relatively unaffected by 100 ppm of accompanying NO, C3H6, CO or H2. XPS measurements show that the increased conductivity in the presence of NH3 was also accompanied by a partial reduction of the surface MoO3. We observed an increase in the resistance of the films after extended time at elevated temperatures. 相似文献