深圳市机动车限行对臭氧浓度影响分析

利用美国EPA开发的区域多尺度空气质量模式CMAQ对2008年8月发生在深圳地区的臭氧污染过程进行模拟,运用brute-force方法分析深圳机动车限行对臭氧浓度变化的影响.研究表明,CMAQ模式能较好的重现模拟期间臭氧的浓度水平和变化趋势;深圳机动车限行造成机动车的排放源削减会提高深圳城区臭氧浓度峰值,数值一般在10μg/m3以下。     

我国机动车污染防治行业技术发展综述

综述了我国机动车污染防治行业的技术发展进展及市场特点,介绍了机动车污染防治行业的新技术开发应用情况,并对行业的骨干企业和市场特点进行了分析。     

宜昌市机动车行驶工况研究

利用GPS车载测试系统对宜昌市轻型客车、轻型卡车、重型卡车和公交车等车型机动车行驶工况分别进行测试。基于测试结果,采用特征参数法合成了宜昌市机动车分车型行驶工况,分析了其特征并与欧美标准工况和5个不同规模城市的机动车行驶工况进行了对比。结果表明：宜昌市机动车行驶平均速度高于ECE15工况,低于FTP-75工况;怠速比例...     

Prenatal diagnosis of charcot-marie-tooth disease type 1a (CMT1A) using molecular genetic techniques

Charcot-Marie-Tooth disease type 1A (CMT1A) is a frequent hereditary motor and sensory neuropathy of the peripheral nerves. In most cases, the disease is associated with a 1.5 Mb tandem duplication at 17p11.2. A 42-year-old pregnant woman requested prenatal diagnosis because of her age and since both her husband and two children were severely affected with CMT1. The CMT1A duplication was demonstrated in the father's, the two children's, and the fetus's DNA using different molecular genetic methods. Although cytogenetical analysis showed a normal female karyotype in the fetus, the parents decided to terminate the pregnancy because of the genetic risk associated with the CMT1A duplication.     

Carbonaceous aerosols in PM10 and pollution gases in winter in Beijing

An intensive observation of organic carbon (OC) and element carbon (EC) in PM10 and gaseous materials (SO2, CO, and O3,) was conducted continuously to assess the characteristics of wintertime carbonaceous aerosols in an urban area of Beijing, China. Results showed that the averaged total carbon (TC) and PM10 concentrations in observation period are 30.2±120.4 and 172.6±198.3 μ/m3, respectively. Average OC concentration in nighttime (24.9±19.6 μ/m3) was 40% higher than that in daytime (17.7±10.9 μ/m3). Average EC concentrations in daytime (8.8±15.2 μ/m3) was close to that in nighttime (8.9±15.1 μ/m3). The OC/EC ratios in nighttime ranging from 2.4 to 2.7 are higher than that in daytime ranging from 1.9 to 2.0. The concentrations of OC, EC, PM10 were low with strong winds and high with weak winds. The OC and EC were well correlated with PM10, CO and SO2, which implies they have similar sources. OC and EC were not well correlated with O3. By considering variation of OC/EC ratios in daytime and night time, correlations between OC and O3, and meteorological condition, we speculated that OC and EC in Beijing PM10 were emitted as the primary particulate form. Emission of motor vehicle with low OC/EC ratio and coal combustion sources with high OC/EC ratio are probably the dominant sources for carbonaceous aerosols in Beijing in winter. A simple method was used to estimate the relative contribution of sources to carbonaceous aerosols in Beijing PM10. Motor vehicle source accounts for 80% and 68%, while coal combustion accounts for 20% and 32% in daytime and nighttime, respectively in Beijing. Averagely, the motor vehicle and coal combustion accounted for 74% and 26%, respectively, for carbonaceous aerosols during the observation period. It points to the motor vehicle is dominant emission for carbonaceous aerosols in Beijing PM10 in winter period, which should be paid attention to control high level of PM10 in Beijing effectively.     

机动车排气污染控制技术与措施

机动车发动机的有害排放物也成为了造成大气污染的一个主要来源,会给人体健康造成了严重的危害,机动车排气污染控制技术和措施包括发动机净化处理技术控制技术,提高燃油的燃烧率,安装防污染处理设备;还包括行政管理手段,实行综合整治,多措并举,减少或消除机动车尾气中有毒有害气体的排放,减轻对大气环境的污染。     

Analysis of precipitation-related motor vehicle collision and injury risk using insurance and police record information for Winnipeg, Canada

Introduction

Police records are the most common source of data used to estimate motor-vehicle collision risks, understand causal or contributing factors, and evaluate the efficacy of interventions. The literature notes concerns about this information citing discrepancies between police reports and other sources of injury occurrence and severity data. The primary objective of the analysis was to assess the adequacy of police reports for an examination of weather-related injury collision risk.

Method

Analyses of relative risk were carried out using both police records and comprehensive insurance claim data for Winnipeg, Canada over the period 1999-2001.

Results and conclusions

Both data sets yielded very similar results—precipitation substantially increases the risk of injury collision (police records: RR 1.76, CI 1.55-2.00; insurance: RR 1.80, CI 1.62-1.99) and risk of injury (police records, RR 1.74, CI 1.55-1.96; insurance, RR 1.69, CI 1.55-1.85) relative to corresponding dry weather control periods. Both rainfall and snowfall were associated with large increases in collisions and injuries.

Impact on Industry

While relative risks are almost identical, over 64% more injury collisions and 74% more injuries were identified using the insurance data, which is an important difference for evaluating absolute risk and exposure.     

基于情景分析的北京市机动车污染排放控制研究

为了研究未来北京市机动车排放控制措施的减排效果,本文基于情景分析法,以2010年为基准年,通过设置3类控制措施情景,估算2011~2020年不同情景下北京市机动车常规污染物排放量,并在基准情景基础上,估算污染物减排量,分析控制措施对不同类型机动车的减排贡献.结果表明,尽管未来北京市机动车保有量会有较大增长,实施机动车排放控制措施仍可取得显著的减排效果.单一措施中,淘汰高排放车减排量最大.其中,淘汰轻型客车可有效减少CO的排放,减排贡献率为89.4%;淘汰重型客车可对NOx、HC和PM10达到有效削减,其贡献率分别为65.5%、55.8%、93.4%.实施新的排放标准对重型柴油车的排放也有明显控制效果,且4种污染物都能得到有效削减.综合实施各种措施的效果最为显著,2020年对CO、NOx、HC、PM10的削减效果分别达到46.4%、42.1%、8.6%和50.6%.     

基于AHP-GCE的固体火箭发动机水射流清理系统安全评价

针对固体火箭发动机水射流清理系统中诸多危险因素所呈现出的复杂性和不确定性,根据水射流清理固体推进剂装药的作业流程,利用层次分析法建立了其安全评价的指标体系,进而采用灰色综合评价法对固体火箭发动机水射流清理系统进行了安全评价。评价结果表明,固体火箭发动机水射流清理系统的综合评价值为31126,处于较高危险状况,需要对其中的危险因素加强防控;水射流清理平台的综合评价值为32417,高于整体综合评价值,因而需要在风险防控中予以着重关注;评价结果与实际情况吻合良好。     

薄壁圆柱壳初始爆破强度的可靠度分析

充分考虑固体火箭发动机壳体的结构特点,建立用中径公式预测其初始爆破强度的方法,对固体火箭发动机壳体爆破强度的可靠度进行了探索。研究表明:①固体火箭发动机壳体实际初始爆破强度与中径公式的名义值之比是符合正态分布的随机变量;②借助于钢制薄壁内压容器的爆破试验数据,在置信度为99%时,得到了该随机变量的分布参数;③应用强度-载荷干涉模型,推导得到了固体火箭发动机壳体爆破强度的可靠度指标计算公式;④固体火箭发动机壳体的可靠度在一定范围内变动。