部分城市空气中颗粒物的元素组成比较

通过对数浓度图和分歧系数对中国广义、武汉、兰州和重庆4座城市空气中粗细颗粒物的42种元素组成进行了比较。结果表明，与人类活动有关的污染元素主要富集在细颗粒物中，而粗颗粒物中元素相对于细颗粒物来说更多的来自于土壤；同一座城市内城区同郊区相比，元素污染更严重，城郊之间细颗粒物中元素在短距离和有利地形下传输作用十分明显。同时还比较了城市之间的元素污染程度。结果表明，兰州城区相对于其它采校点位颗粒物中元素污染较为     

可吸入颗粒物研究现状及发展综述

可吸入颗粒物严重影响空气质量和人体健康。人类对可吸入颗粒物的研究已经取得了相当多的成果,对其来源、组分及形成等都有了一定的认识。本文详细的综述了这部分内容,并对可吸入颗粒物的采样、分离和分析方法都做了介绍。更深层的认识可吸入颗粒物的生成机理和脱除手段是以后努力研究的方向。     

Air quality at a snowmobile staging area and snow chemistry on and off trail in a Rocky Mountain subalpine forest, Snowy Range, Wyoming

A study was begun in the winter of 2000–2001 and continued through the winter of 2001–2002 to examine air quality at the Green Rock snowmobile staging area at 2,985 m elevation in the Snowy Range of Wyoming. The study was designed to evaluate the effects of winter recreation snowmobile activity on air quality at this high elevation site by measuring levels of nitrogen oxides (NO _x , NO), carbon monoxide (CO), ozone (O₃) and particulate matter (PM₁₀ mass). Snowmobile numbers were higher weekends than weekdays, but numbers were difficult to quantify with an infrared sensor. Nitrogen oxides and carbon monoxide were significantly higher weekends than weekdays. Ozone and particulate matter were not significantly different during the weekend compared to weekdays. Air quality data during the summer was also compared to the winter data. Carbon monoxide levels at the site were significantly higher during the winter than during the summer. Nitrogen oxides and particulates were significantly higher during the summer compared to winter. Nevertheless, air pollutants were well dispersed and diluted by strong winds common at the site, and it appears that snowmobile emissions did not have a significant impact on air quality at this high elevation ecosystem. Pollutant concentrations were generally low both winter and summer. In a separate study, water chemistry and snow density were measured from snow samples collected on and adjacent to a snowmobile trail. Snow on the trail was significantly denser and significantly more acidic with significantly higher concentrations of sodium, ammonium, calcium, magnesium, fluoride, and sulfate than in snow off the trail. Snowmobile activity had no effect on nitrate levels in snow.     

传感技术在环境空气监测中的方法适用性研究

采用某品牌3台传感器,对环境空气中气态污染物(NO_2、SO_2、O_3、CO)和颗粒物(PM_(10)、PM_(2.5))进行为期1个月的连续监测,探讨传感技术在环境空气监测中的方法适用性。研究表明,3台传感器监测的各污染物质量浓度均显著相关,Pearson相关系数0.9(p0.01);监测的颗粒物与国控点数据显著相关且质量浓度水平接近,Pearson相关系数0.9(p0.01);PM_(2.5)传感器测定值相对于国控点数据的平均相对误差仅为-7.3%,均值绝对误差2μg/m~3;传感器在高湿度下的PM_(2.5)测定值与国控点数据相吻合,当相对湿度为80%～90%时,平均相对误差仅为-0.9%;传感器气态污染物测定值与国控点数据之间存在差异,电化学原理气态污染物传感器性能仍有待提升。     

Palm oil biodiesel: An assessment of PAH emissions, oxidative potential and ecotoxicity of particulate matter

This work assessed the impact of fuelling an automotive engine with palm biodiesel (pure, and two blends of 10% and 20% with diesel, B100, B10 and B20, respectively) operating under representative urban driving conditions on 17 priority polycyclic aromatic hydrocarbon (PAH) compounds, oxidative potential of ascorbic acid (OP^AA), and ecotoxicity through Daphnia pulex mortality test. PM diluted with filtered fresh air (WD) gathered in a minitunel, and particulate matter (PM) collected directly from the exhaust gas stream (W/oD) were used for comparison. Results showed that PM collecting method significantly impact PAH concentration. Although all PAH appeared in both, WD and W/oD, higher concentrations were obtained in the last case. Increasing biodiesel concentration in the fuel blend decreased all PAH compounds, and those with 3 and 5 aromatic rings were the most abundant. Palm biodiesel affected both OP^AA and ecotoxicity. While B10 and B20 exhibited the same rate of ascorbic acid (AA) depletion, B100 showed significant faster oxidation rate during the first four minutes and oxidized 10% more AA at the end of the test. B100 and B20 were significantly more ecotoxic than B10. The lethal concentration LC50 for B10 was 6.13 mg/L. It was concluded that palm biodiesel decreased PAH compounds, but increased the oxidative potential and ecotoxicity.     

汽车尾气颗粒物对动物肺泡巨噬细胞的免疫毒性及比较

研究汽车尾气颗粒物气管染毒后对大鼠肺泡巨噬细胞免疫功能的影响，结果是动物肺泡巨噬细胞Ｆｃ受体表达、ＡＭ抗肿瘤细胞毒作用、抗体介导细胞毒作用受到抑制，具有明显的剂量效应关系；总体比较，汽油车尾气颗粒物对ＡＭ免疫功能影响较柴油车严重。     

乌鲁木齐市大气PM2.5中重金属元素含量和富集特征

利用PM2.5／PM10便携式采样器采集了乌鲁木齐市5个功能区PM2.5,样品,用TAS-990石墨炉原子吸收光谱仪检测了PM2.5样品中Cd、Cu、Ni、Pb、Mn的含量。结果表明,乌鲁木齐大气PM2.5质量浓度变化趋势是冬季采暖盛期〉秋季采暖初期〉春季停暖初期〉夏季停暖期。参照《环境空气质量标准》（GB3095—2012）中的二级标准,采样期间卡子湾水泥厂区样品全部超标,其余4个采样点样品在冬季采暖盛期也全部超标,部分样品在非采暖期超标。富集因子法分析表明,乌鲁木齐市5个采样区PM2.5样品中Ni、Cu、Cd、Pb污染主要来自于人类活动,Mn则来源于地壳物质。     

Filter badge SO_2捕集-离子色谱法测定空气中二氧化硫

用Filter badge SO2捕集空气中SO2。用双氧水将捕集到的SO2氧化成SO42-,再用离子色谱法测定SO42-的浓度,按公式f SO2=2082×103×(T/τ)X计算,即可得到捕集时间内的平均SO2浓度f SO2(ppb)。     

柴油车加载减速烟度测试工况的关联规则研究

进行在用柴油车加载减速烟度检测工况点的关联规则研究。应用数据挖掘方法对4730台次柴油车的加载减速烟度排放检测数据进行分析,挖掘该检测方法中的三种检测工况点测试烟度值HSU100、HSU90、HSU80合格与否相互之间的关联规则。发现该三种检测工况烟度排放检测合格的相互支持度在85.8%~90.68%范围内,而其中任一种检测工况下烟度测试合格相对车辆烟度检测合格的支持度为77.8%。     

宁波市颗粒物中多环芳烃浓度水平、分布及来源分析

讨论了2003年宁波市颗粒物中多环芳烃浓度水平、分布及来源,结果表明,PM10中PAHS占TSP中总量的83%,PM2.5中的PAHS占TSP总量的54%,颗粒物中多环芳烃主要存在于小于10μm的颗粒中。颗粒物中多环芳烃季节变化特征明显,夏季最低,冬季最高。汽车尾气对PM10中多环芳烃的贡献率达56%,汽车尾气是颗粒物中多环芳烃的主要来源。