一、概述发动机排放物(NOx、CO、HmCn等)连同臭味、噪音被一致公认为是人类环境的巨大污染源之一。随着我国国民经济的发展,汽车保有量增加,大中城市以及工矿区,汽车发动机所引起的空气污染将越来越严重。国产汽车现尚未大规模地装有排气净化系统,在此情况下,如何改善现有汽车发动机有害物的排放就成为一个日益紧迫的研究课题。目前,虽然我 I. Overview Engine emissions (NOx, CO, HmCn, etc.), along with odor, are unanimously recognized as one of the major sources of pollution to the human environment. With the development of our country’s national economy, the number of car ownership increases. Air pollution caused by automobile engines in large and medium-sized cities as well as industrial and mining areas will become more and more serious. Domestic cars are not yet equipped with large-scale exhaust gas purification system, in which case, how to improve the existing car engine harmful emissions has become an increasingly urgent research topic. At the moment, though I am