【摘 要】
：
近年来,随着人们对环境的保护日趋重视。特别是近些年来,随着城市里的汽车越来越多,我国大部分地区被雾霾天气笼罩。研究表明,雾霾天气形成主要原因之一——汽车尾气是主要的
论文部分内容阅读
近年来,随着人们对环境的保护日趋重视。特别是近些年来,随着城市里的汽车越来越多,我国大部分地区被雾霾天气笼罩。研究表明,雾霾天气形成主要原因之一——汽车尾气是主要的污染物。因此现在世界各国对内燃机废气排放的要求及标准也越来越高了。
In recent years, people attach more importance to the protection of the environment. Especially in recent years, with more and more cars in the cities, most parts of our country are shrouded in haze and fog. Research shows that one of the main causes of fog and haze weather - automobile exhaust is the main pollutant. Therefore, the requirements and standards of the internal combustion engine exhaust emission in various countries in the world are also getting higher and higher now.
其他文献
研究流化冰预冷与冰温贮藏(-1.5℃)技术对新鲜鳕鱼片质量的影响.感官检验QDA(定量描述分析方法)数据的多元变量分析(ANOVA)用统计软件NCSS 2000(NCSS,Utah,USA)实现.对QDA数
稻纵卷叶螟,二化螟是淮北地区单季稻上的主要害虫,特别是自2003年稻纵卷叶螟在该地区大暴发以来,连年大发生,严重威胁水稻的高产稳产.
Forty-five species of wild edible fruits were identified and traditional local knowledge of their usage was recorded in 40 villages of Kodagu district in Centra
2000年Krause A等[1]首先从人血液中分离纯化的一种由肝脏分泌的小分子抗菌肽,称之为肝脏表达的抗菌多肽(1iver-expressed antimicrobial peptide,LEAP-1).2001年Park CH等[2
This paper reports on the effect of various micropropagation factors of Gmelina arborea Roxb. through multiple shoot induction. Factors like the source and age
本文简单介绍了AFLP技术的原理、发展和在茶树中的应用,同时也对AFLP的几种改进技术在茶树中的应用前景做了简要分析。
This article briefly introduces the principle, de
Loss of mangroves and consequent habitat fragmentation is a major concern throughout the world’s tropical countries. Conversion of mangrove habitat due to aqua
We investigated the influence of different levels of osmotic stress on growth and development in selected wild almond species (eight Prunus spp.) grown in vitro
目的 探讨苯并[a]芘对大鼠学习记忆功能、NO和iNOS的影响.方法 健康雄性SD大鼠40只,经麻醉后定位插管,一周后称重,按体重将动物随机分为4组:橄榄油组(溶剂对照组)、B[a]P 2.5
教育部颁布以后,信息技术教学形势一片大好.信息技术教学普遍受到不同程度的重视.笔者在分析了信息技术教学的现状、信息技术教学的特点以后,从教学实践出发,根据信息技术教