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41.
高雪峰 《铁路通信信号工程技术》2014,(1):15-19
重点对车载安全数字输入输出模块进行故障导向安全部分的分析,从理论分析到模拟仿真,到各种测试方法,研究了VDX模块的可靠性. 相似文献
42.
根据地铁变电站自动化的结构特点,介绍说明新型通信管理机在地铁变电站自动化中的应用研究现状,并结合现场总线技术及变电站自动化发展的趋势提出了一种新型的采用通信管理机的自动化系统解决方案。 相似文献
43.
Vehicles are considered to be an important source of ammonia (NH3) and isocyanic acid (HNCO). HNCO and NH3 have been shown to be toxic compounds. Moreover, NH3 is also a precursor in the formation of atmospheric secondary aerosols. For that reason, real-time vehicular emissions from a series of Euro 5 and Euro 6 light-duty vehicles, including spark ignition (gasoline and flex-fuel), compression ignition (diesel) and a plug-in electric hybrid, were investigated at 23 and −7 °C over the new World harmonized Light-duty vehicle Test Cycle (WLTC) in the Vehicle Emission Laboratory at the European Commission Joint Research Centre Ispra, Italy. The median HNCO emissions obtained for the studied fleet over the WLTC were 1.4 mg km−1 at 23 °C and 6 mg km−1 at −7 °C. The fleet median NH3 emission factors were 10 mg km−1 and 21 mg km−1 at 23 and −7 °C, respectively. The obtained results show that even though three-way catalyst (TWC), selective catalytic reduction (SCR), and NOx storage catalyst (NSC) are effective systems to reduce NOx vehicular emissions, they also lead to considerable emissions of the byproducts NH3 and/or HNCO. It is also shown that diesel light-duty vehicles equipped with SCR can present NH3 emission factors as high as gasoline light-duty vehicles at both, 23 and −7 °C over the WLTC. Therefore, with the introduction in the market of this DeNOx technology, vehicular NH3 emissions will increase further. 相似文献