液化石油气汽车颗粒物数量排放特征的研究

利用颗粒物数量测试仪器ELPI对瞬态循环下的汽油车和液化石油气汽车进行颗粒物排放测量.结果表明,两种车辆排放的颗粒物中,粒径小于70nm的颗粒物均占绝对优势,占总排放的80％～ 90％;大于490nm的颗粒物在总排放中的比例均非常小.且颗粒物数量排放浓度随着车速的升高而增加,尤其是车速超过70km/h后,颗粒物数量排放随车速的增幅升高.但两种车辆相对比较,汽油车排放的颗粒物数量比液化石油气汽车多.     

柴油机微粒生成及控制技术

在总结柴油机微粒排放的生成机理的基础上,分析了影响柴油机微粒生成的各种因素。通过对柴油机微粒各种净化方式的比较,总结指出了柴油机微粒处理的发展趋势。     

The contribution of road traffic to particulate matter and metals in air pollution in the vicinity of an urban road

A detailed investigation was conducted to study the sources of particulate matter in the vicinity of an urban road in Žilina. To determine the amount of particulate matter (PM₁₀, PM_2.5 and PM₁) present in the ambient air, a reference gravimetric method was used. The main objective of this contribution was to identify the sources of these particles by means of statistical methods, specifically principal component analysis (PCA), factor analysis (FA), and absolute principal component scores (APCS), as well as using the presence of 17 metals in the particulate matter (Na, Mg, Al, Ca, V, Cr, Fe, Mn, Ni, Cu, Zn, As, Mo, Sb, Cd, Ba, Pb). To identify the metals in the particulate matter samples and to determine their abundances, spectroscopic methods were used, specifically inductively coupled plasma mass spectrometry (ICP-MS). Each of these metals may come from a specific source, such as the burning of fossil fuels in fossil fuel power plants; local heating of households; the burning of liquefied fossil fuels in the combustion engines of vehicles; the burning of coal and wood; non-combustion related emissions resulting from vehicular traffic; resuspension of traffic-related dust; and industry. Diesel vehicles and non-combustion emissions from road traffic have been identified as two key sources of the particulate matter. The results reveal that non-combustion emissions, which are associated with the elements Na, Fe, Mn, Ni, Zn, Mo, Sb, Cd, and Pb, are the major contributors, followed by combustion emissions from diesel vehicles, which are associated with the elements Mg, Ca, and Ba.     

浅谈采用P.O42.5R水泥浇筑C50混凝土箱梁的工艺质量控制

阐述了采用P.O42.5R早强水泥浇筑C50混凝土的工艺质量控制。     

车载PM2.5检测标定方法的研究

设计和搭建环境温度标定台架和整车乘客舱模拟台架系统,制定PM2.5总成传感器的标定方法;通过标定台架的模拟试验,从温度性、净化速率影响等方面对其是否能满足性能要求进行验证分析。     

后张法50m预应力T型梁施工控制

结合工程实际．从施工准备、钢绞线的力学性能、混凝土施工、施加预应力、孔道压浆等几个方面探讨后张法50m预应力T梁的施工控制方法，对同类工程的施工有一定的指导意义。     

多相大功率永磁无刷直流电机控制器的研究

本文提出了一种采用晶闸管元件构成的多相大功率永磁无刷直流电动机控制器的新方案.着重分析了这种新型控制器的工作原理和可靠换流过程,介绍了多单元驱动器同步控制方法,提供了基于80C196KC单片机为核心的控制单元的结构图,论文最后给出了样机的试验结果.     

柴油质量对NOx和PM排放的影响及控制措施

控制柴油机排放的关键在于控制NOX和PM的排放,主要依赖于柴油品质的提高和后处理技术的发展。文中重点分析了柴油性质中硫、芳烃、十六烷值和馏程对NOX和PM排放的影响,探讨了当前用于控制NOX和PM的主要后处理技术。     

论汽车排放污染控制与治理之浅见

当今社会,汽车已经成为人们出行的重要交通工具,随着汽车保有量的增加汽车排气污染也变得日益严重,阴霾天、PM2.5就是最直接的影响,温室气体CO2的排放量也是一个很客观的量。因此,加强汽车排放污染的控制与治理是必须的。     

机桨一体化推进电机的设计与分析

设计了一种新型的适用于机桨一体化水下推进器的大气隙永磁电机,电机转子磁极采用Halbach结构。针对该新型永磁电机的特点,采用有限元法对电机进行了电磁场分析,在计及定转子相对运动及定子斜槽等因素的条件下,计算了电动机的空载及负载磁场分布、空载气隙磁密、空载反’电势以及负载运行特性,计算结果表明电机的各项指标均能满足工程需要。