太原市2022年1月份PM2.5变化特征

利用 PM_2.5在线监测仪、在线气体 / 气溶胶监测仪(Marga)及单颗粒气溶胶质谱仪(SPAMS)分析了太原市2022 年 1 月份 PM_2.5浓度、组分变化特征及其来源,研究表明,太原市 1 月份 PM_2.5平均质量浓度为 86 μg/m³,质量浓度变化呈现北部低南部高的特征。在 PM_2.5各组分中,二次生成离子 SO₄^2-、NO₃^-、NH₄⁺是最主要组分,占比为PM_2.5的 39.0%。PM_2.5在线来源解析结果表明,工业工艺源、燃煤源及二次无机源为最主要的污染物来源,研究显示,重点污染源主要来自于太原市的西南部。     

太原市沙尘期间PM2.5变化特征

利用PM_2.5在线监测仪、在线气体/气溶胶监测仪(Marga)、半连续热光分析仪(OCEC)、在线重金属监测仪(CES)、单颗粒气溶胶质谱仪(SPAMS)分析了太原市沙尘期间PM_2.5浓度、组分变化特征及来源情况。研究表明,沙尘期间,环境空气质量迅速恶化,PM_2.5浓度升高明显。在PM_2.5组分分析中,沙尘期间,SO₄^2-、NO₃^-、NH₄⁺二次离子浓度有所下降,OC、EC变化不大,金属元素浓度增幅明显。PM_2.5在线来源解析表明,沙尘期间扬尘源占比大幅增加,矿物质颗粒物和含左旋葡聚糖颗粒物占比也有不同程度增加。     

太原市元宵节期间PM2.5变化特征

利用PM_2.5在线监测仪、在线气体 / 气溶胶监测仪(Marga)、半连续热光分析仪(OCEC)、单颗粒气溶胶质谱仪(SPAMS)分析了太原市 2020 年元宵节期间 PM_2.5质量浓度、组分变化特征及来源情况,研究表明,元宵节期间,PM_2.5浓度升高明显,由于太原市地形和风向原因,PM_2.5浓度变化呈现由南到北逐渐升高的特征,且南部点位峰值高于北部点位。在 PM_2.5组分分析中,SO₄^2-、NO₃^-、NH₄⁺二次离子的大量生成是 PM_2.5浓度升高的主要因素。PM_2.5在线来源解析结果表明,机动车尾气源、工业工艺源及二次无机源是最主要的污染物来源。烟花爆竹燃放分析结果表明,太原市南部点位及城乡结合部分点位受烟花爆竹燃放影响较为明显,烟花燃烧特征离子 Mg²⁺、Ba²⁺     

北京市某街道采暖期与非采暖期环境空气颗粒物(PM2.5)组分特征及来源分析初探

本文于采暖期(2021 年 12 月～2022 年 1 月)和非采暖期(2022 年 3 月～4 月)对北京市某街道共计两个点位进行环境空气颗粒物PM_2.5浓度及组分(水溶性离子、碳质组分、无机元素)监测。结果显示：两个点位在采暖期和非采暖期 PM_2.5浓度分别为 37 μg/m³、39 μg/m³,水溶性离子中以 NO₃^-、SO₄^2-、NH₄⁺为主要组分,碳质组分以 OC 为主,无机元素中 Fe、Zn、Al、S、Si 五种元素的浓度相对较高。通过质量重构结果表明,OM、NO₃^-、SO₄^2-、NH₄⁺、地壳物质的占比较高(超过 90 %),在采暖期期间 PM_2.5组分主要来源于化石燃料燃烧和机动车排放的 NO_...     

PM2.5的研究现状及防控对策

PM2.5空气中最重要的污染物之一。它粒径小、组分复杂、可为毒性物质提供载体,影响大气环境质量,并危及人体健康。本文主要围绕PM2.5的组成、化学特征、来源解析及其对环境和健康的危害等方面进行论述,有针对性的提出了几点控制途径和防控政策。     

以机动车污染防治推进PM2.5治理问题探讨

随着城市经济的快速发展,我国机动车保有量呈快速增长态势,机动车尾气污染已成为大中城市空气污染的主要来源之一,所引起大气PM2.5污染问题已引起社会和公众的高度关注,分析大气PM2.5成因及机动车排气污染状况,结合城市机动车污染防治工作,提出污染防治工作对策,对推进大气PM2.5治理进程意义重大。     

大气颗粒物PM2.5化学组分分析方法概述

大气细颗粒物PM2.5中化学组分的分析方法做了简要的介绍,PM2.5的化学组分主要包括水溶性离子、无机元素、有机碳和元素碳,并分析了各种方法的优缺点,以便于在研究中选取更简单有效的方法,并展望了PM2.5中组分的研究前景.     

炼油厂典型工艺PM2.5排放与防治

近年来频频爆发的灰霾天气,PM2.5是一个很大原因。石油化工行业排放的废气涵盖了PM2.5的直接排放与二次排放污染源。加之国家正在逐步提高对于炼油厂废气排放标准。因此本文介绍PM2.5的物理化学特性,以及对环境和人体产生的影响;统计炼油厂废气的特征排放源以及排放物,查阅相关文献,从生产工艺和改良设备方面,对典型工艺进行防治措施的探究。     

PM2.5的研究现状及健康效应

大气细颗粒物PM2.5是大气气溶胶的一部分,由于其粒径小以及可为毒性物质提供载体,对环境和人体健康产生很大的影响。文章总结了国内外有关细颗粒物PM2.5的研究现状,主要围绕PM2.5的物理化学特征、来源解析、健康效应、及其对能见度的影响等方面进行论述,并对其研究动向进行了展望。     

上海宝山区细颗粒气溶胶PM2.5特征

为了探讨上海宝山区细颗粒气溶胶PM2.5特征,于2008.9.1-2009.8.31连续采集了细颗粒气溶胶PM2.5样品。分别分析了空气中PM2.5的质量浓度水平以及空气中以PM2.5存在的金属元素质量浓度水平,结果显示：PM2.5的年均质量浓度达33.70μg/m3;冬季细颗粒气溶胶质量浓度水平最高达44.35μg/m3,超标情况最为严重,超标率达37.5%;同时,检测出的11种金属元素在四季空气中的总浓度分别为：0.320μg/m3、0.384μg/m3、0.326μg/m3、0.218μg/m3。     

PM1.0 and PM2.5 Characteristics in the Roadside Environment of Hong Kong

Daily mass concentrations of PM _1.0 (particles less than 1.0 μm in diameter), PM _2.5 (particles less than 2.5 μm in diameter), organic carbon (OC), and elemental carbon (EC) were measured from January through May 2004 at a heavily trafficked sampling site in Hong Kong (PU). The average concentrations for PM _1.0 and PM _2.5 were 35.9 ± 12.4 μ g cm ^{? 3} and 52.3 ± 18.3 μ g cm ^{? 3} . Carbonaceous aerosols were the dominant species in fine particles, accounting for ～ 45.7% of PM _1.0 and ～ 44.4% of PM _2.5 . During the study period, seven fine-particle episodes occurred, due to the influence of long-range transport of air masses from mainland China. PM _1.0 and PM _2.5 responded in similar ways; i.e., with elevated mass and OC concentrations in those episode days. During the sampling period, PM _1.0 OC and EC generally behaved similarly to the carbonaceous aerosols in PM _2.5 , regardless of seasonal variations and influence by regional pollutions. The low and relatively constant OC/EC ratios in PM _1.0 and PM _2.5 indicated that vehicular emissions were major sources of carbonaceous aerosols. PM _1.0 and PM _2.5 had the same dominant sources of vehicular emissions in winter, while in spring PM _2.5 was more influenced by PM _{1 ? 2.5} (particles 1–2.5 μ m in diameter) that did not form from vehicle exhausts. Therefore, PM _1.0 was a better indicator for vehicular emissions at the Roadside Station.     

广州冬季PM10和PM2.5中有机碳与元素碳浓度水平及分布特征

于2002年1月至2月在广州市3个点采集不同粒径(PM2.5和PM10)大气气溶胶样品,测定了PM2.5,PM10及其中的有机碳(OC)和元素碳(EC)浓度,探讨了广州市冬季碳气溶胶的污染特征.结果表明,PM2 5和PM10平均浓度分别为105.9 μg/m3及161.7 μg/m3,其中PM25中的OC,EC浓度分别为22.6μg/m3和8.3μg/m3,PM10中的OC,EC浓度分别为29.4和10.4 μg/m3.PM2.5和PM10的总碳气溶胶含量分别为40.5%和35.7%.PM2.5和PM10中OC/EC的比值平均为2.7,这与大多数城市大气的OC/EC比值接近.OC与EC的相关性很好(R＞0.9),表明OC与EC的排放源相同.估算的PM2.5中次生有机碳(SOC)平均浓度为12.1μg/m3,占PM2.5中总OC浓度的49.6%;PM10的SOC平均浓度为14.3 μg/m3,占PM10中总OC的44.8%.     

East versus West in the US: Chemical Characteristics of PM2.5 during the Winter of 1999

The chemical composition of PM_2.5 was investigated at four sites (Rubidoux, CA, Phoenix, AZ, Philadelphia, PA, and Research Triangle Park, NC) in January and February of 1999. Three samplers were used to determine both the overall mass and the chemical composition of the aerosol. Teflon filters were weighed for total mass. Ions were analyzed using ion chromatography. Elements were determined using X-ray fluorescence. Organic and elemental carbon were measured using a thermo-optical method. At all of the sites, reconstructed mass was observed to be greater than or equal to the measured mass. Good ionic balance was found for ammonium, nitrate, and sulfate at each of the sites. Overall, the chemical composition of the aerosol for each site was in good agreement with the expected composition based upon previous studies, with the exception of relatively high nitrate contribution to the total mass at Philadelphia. Good agreement was found between the predicted amount of sulfate by XRF analysis of sulfur and the sulfate measured by ion chromatography. As expected, sulfate was a more important contributor to the total mass at the East Coast sites. Nitrate contributed more to the total mass at the West Coast sites and was an important factor in the highest observed mass concentration at Rubidoux. Teflon filters appear to lose nitrate to a greater extent than heat-treated quartz fiber filters. Organic carbon was also found to be the largest part of the aerosol mass on minimum days for all sites and a significant portion of the mass on other days with 25-50% of the total mass at all of the sites. At three of the sites, organic carbon (OC) collected on denuded filters was less than that found on nondenuded samples, indicating an absorptive artifact on the quartz fiber filters. It was also found that the crustal component to PM_2.5 was highest at Phoenix. PM_2.5 was also found to contribute significantly to the PM₁₀ particle mass at all the sites.     

Characteristics of PM2.5 Episodes Revealed by Semi-Continuous Measurements at the Baltimore Supersite at Ponca St

Highly time-resolved measurements of PM_2.5, its major constituents, particle size distributions (9 nm to 20 μ m), CO, NO/NO₂, and O₃, and meteorological parameters were made from February through November 2002, at the Baltimore Supersite at Ponca St. using commercial and prototype semi-continuous instruments. The average PM_2.5 mass concentration during the study period was 16.9 μ g/m³ and a total of 29 PM_2.5 pollution episodes, each in which 24-h averaged PM_2.5 mass concentrations exceeded 30.0 μ g/m³ for one or more days, were observed. Herein, 6 of the worst episodes are discussed. During these events, PM_2.5 excursions were often largely due to elevations in the concentration of one or two of the major species. In addition, numerous short-term excursions were observed and were generally attributable to local sources. Those in OC, EC, nitrate, CO, and NO_x levels were often observed in the morning traffic hours, particularly before breakdown of nocturnal inversions. Moreover, fresh accumulation aerosols from local stationary combustion sources were observed on several occasions, as evidenced by elevations in elemental markers when winds were aligned with sources resulting in PM_2.5 increments of ～ 17 μ g/m³. Overall, the results described herein show that concentrations of PM_2.5 and its major constituents vary enormously on time scales ranging from < 1 hr to several days, thus imposing a more highly complex pattern of pollutant exposure than can be captured by 24-hr integrated methods, alone. The data suggest that control of a limited number of local sources might achieve compliance with daily and annual PM_2.5 standards.     

鞍山市建成区PM2.5的污染物特征分析

本次对鞍山市PM_(2.5)的监测及分析,借助于CMB等一系列的相关技术手段,对鞍山市的空气质量状况进行监测,并给出相应的建议与改进措施。本次研究表明,鞍山市的空气污染在冬季相对较为严重,而其他季节也存在一定的污染超标状况。针对这些问题,环保部门应加强管理,强化监管机制,防止空气污染。     

广州市黄埔区降水的化学特征及来源解析

以2006年广州市黄浦区降水样品监测资料为基础对广州市工业区降水的化学特征进行了分析,结果表明黄浦区降水样品pH值分布范围在3．56—6．41,雨量加权平均值为4．44。降水的酸雨频率为94．6％,降水中的主要阴离子为SO4^2-和NO3-,分别占阴离子总量的50．6％和29．8％;主要阳离子是Ca2＋和NH4＋分别占阳离子总量的52．6％和30．5％。相对酸度（FA）计算结果表明约有67．6％的降水酸度被碱性成分的Ca2＋和NH4＋中和。此外,利用富集系数方法,计算了降水中重要离子的来源,结果表明SO4^2-和NO3-主要来源于人类活动,而Ca2＋和K＋主要来源于岩石／土壤风化。     

我国PM2.5中可溶性无机离子组分的来源及特点

由于人类活动的影响,阴霾天的范围在不断扩大,并且两年频率越来越高,严重影响人们的生活及身体健康。PM2.5是造成阴霾天的主要原因,其中的可溶性无机离子组分的强吸水能力又加重了PM2.5对环境的污染程度。本文从现有的研究中总结我国PM2.5中可溶性无机离子组分的来源及特点,对于正确认识PM2.5的特征及今后开展相应研究有一定引导作用。     

PM10/PM2.5/PM1 Data from a Trichotomous Sampler

ABSTRACT

As part of an effort to determine whether 1 μm or 2.5 μam is the better choice for a new fine particulate matter standard, Professor Virgil A. Marple of the University of Minnesota developed a high volume trichotomous (PM₁₀/PM_2.5 /PM₁) sampler. Two of these samplers were used to obtain particulate matter (PM) samples at a site located in Phoenix, Arizona, from May 1995 through October 1995. All filter samples were analyzed for mass concentrations and a few for elemental and chemical compositions. Relative fractions were determined for PM₁₀, PM_2.5, PM₁, PM_2.5–10, and PM_1–2.5. Calculations were made to evaluate how coarse and fine mode aerosol contributed to the intermediate size range. Results indicated that most of the PM₁₀ in Phoenix was coarse mode PM (windblown dust), which was also a primary contributor to PM₂₅.     

PM 2.5 Semivolatile Organic Material at Riverside,California: Implications for the PM 2.5 Federal Reference Method Sampler

Particulate semivolatile organic compounds can be lost from particles on a filter during sample collection and storage, resulting in a negative artifact. Gas-phase organic compounds can adsorb on a quartz filter to cause a positive artifact. A sampler (Particle Concentrator-Brigham Young University Organic Sampling System: PC-BOSS) has been developed that uses a cyclone and virtual impactor (particle concentrator) inlet to provide a concentrated stream of 0.1-2.5 w m particles. The concentrator is followed by a BOSS diffusion denuder to remove interfering gas-phase compounds and filter packs to collect particles, including any semivolatile species lost from the particles during sampling. The sampler can be used for the determination of both fine particulate nitrate and semivolatile organic material without significant "positive" or "negative" sampling artifacts. The sampler has been evaluated at Riverside, CA. The collection efficiency of the particle concentrator was stable, being 65% - 2% and 61% - 1% for particulate sulfate and soot, respectively. Results obtained with the PC-BOSS for the determination of PM 2.5 organic material including semivolatile components agreed with results from a BOSS, but not with filter pack results. The precision of the PC-BOSS results for particulate organic material was - 8%. An average of 50% of the particulate organic material was lost from the particles during sampling for all samplers used. As a result of the loss of semivolatile organic material and nitrate, the PM 2.5 Federal Reference Method sampler underdetermined PM 2.5 by an average of 34% with the under measurement varying from negligible to 27 w g/m 3 , averaging 8.9 w g/m 3 .