灰霾期间大气颗粒物污染特征研究进展

近年来,随着经济的迅速发展和城市化进程的加快,灰霾天气呈现增加的趋势,引起了社会的高度关注。综述了灰霾发生时大气颗粒物污染水平、粒径分布和垂直分布特征,大气颗粒物重要化学成分(水溶性离子、有机碳和元素碳、金属元素)的浓度水平和粒径分布特征及大气颗粒物的来源解析方法,并提出灰霾主要防治措施。     

大气颗粒物中颗粒微观形貌特征及其矿物组成分析

为探索大气颗粒物的矿物组成及其单颗粒的微观形貌特征,以绵阳市为例,通过对绵阳市3个不同功能区(工业区、商业区、科技生活区)采集大气颗粒物以及对PM10进行24h监测,利用扫描电镜能谱分析方法(SEM/EDS)对绵阳市不同功能区中大气颗粒物的微观形貌及其矿物组成进行了研究,同时结合PM10监测结果分析各区域颗粒物污染现状。研究结果表明:不同功能区大气颗粒物主要由规则形态颗粒和不规则形态颗粒组成;规则颗粒主要为矿物颗粒,不规则颗粒主要由烟尘集合体、燃煤飞灰颗粒和不规则矿物等组成。工业区矿物颗粒主要为石膏、硫酸盐类、硅酸盐类矿物,商业区和科技生活区主要为硅酸盐类矿物。工业区不规则颗粒占比较大,商业区和科技生活区矿物颗粒相对较少;且同一功能区内细粒级主要为规则形状的矿物颗粒,而粗粒级主要为不规则形态的颗粒物。PM10监测结果显示,3个功能区颗粒物污染均较严重。     

颗粒物污染

颗粒物污染(pollution by particulates)是指悬浮在空气中的固体或液体颗粒物,会对生物和人体健康造成危害。颗粒物的种类很多,一般指0.1至75μm的尘粒、粉尘、雾尘、烟、化学烟雾和煤烟。其危害特点是粒径1μm以下的颗粒物沉降慢、波及面大而远。无论是来源于自然     

广州大气颗粒物与酸沉降的关系研究

本文研究了大气颗粒物的酸度和酸缓冲能力,实验证实广州大气颗粒物中存在着游离的硫酸,其水溶性离子中SO4^2-及NO3^-占很大的比例。颗粒物中的碱性成分含量大于酸性成分,对酸性降水有一定的缓冲能力。气溶胶中细颗粒物的酸性大于粗颗粒物,且酸缓冲能力远低于粗颗粒物。     

某市工业区和市区环境空气颗粒物中重金属污染特征

对某市工业区和市区2023年的大气环境进行监测,分析了其环境空气颗粒物的浓度分布以及环境空气颗粒物中重金属的污染特征,并采用富集因子法对重金属的来源进行了探讨。结果表明,某市环境空气颗粒物浓度呈现出季节性的变化规律,春冬季节颗粒物污染高于夏秋季,且工业区环境空气颗粒物浓度高于市区;环境空气颗粒物中重金属浓度呈现一定的时空分布,工业区的重金属浓度分布普遍高于市区,砷的污染较为突出,而重金属元素镉、铅和砷出现了严重的富集,表明人为造成的重金属污染极其严重。因此,需在实际生产生活过程中减少人为因素导致的重金属的排放。     

原水颗粒物对超滤膜通量的影响及其污染机理

随着原水水质的日益恶化和水厂出水指标逐渐严苛,自来水厂常规处理工艺面临着严峻的考验与挑战。超滤膜技术在现有水厂技术改造及深度处理扩建领域具有广泛的应用空间和价值。不同类型、浓度的原水颗粒物对超滤膜通量及污染机理的影响存在明显的差异。该文针对原水颗粒物的类型和浓度,开展系统的试验研究与分析,以便为超滤膜在自来水厂提标改造工程中的应用提供理论依据。     

北京市大气颗粒物中多环芳烃的分布特征

用撞击式分级采样器同步采集了北京市城乡结合部、郊区的2003年4个季节的不同粒径大气颗粒物样品,用气相色谱-质谱分析了其中的多环芳烃,并对两个地区大气颗粒物中的多环片烃含量、分布及季节性变化特征进行了探讨。     

安徽省大气细颗粒物污染特征及来源解析

基于2015-2020年安徽省空气质量监测和PM_2.5化学组分等逐小时数据,分析了安徽省颗粒物污染特征和污染来源。结果表明,2015-2020年期间全省呈现PM_2.5日均浓度低值日增多、高值日减少的趋势,其中浓度高值主要分布在秋冬季和春末夏初,局部短期污染和区域重污染过程显著,逐步向PM_2.5与O₃复合污染类型转变。2020年全省PM_2.5化学组分中占比较高的三个组分为有机物(28.2%)、硝酸盐(21.6%)和硫酸盐(12.1%)。PMF结果表明,安徽省PM_2.5最主要的来源是二次硝酸盐,其占比范围在26.3%～38.3%之间,其次为二次硫酸盐、燃煤、工业排放和机动车排放。     

浅谈细颗粒物(PM2.5)污染与化石燃料燃烧

简要论述了细颗粒物(PM2.5)污染的危害,煤燃烧以及使用汽柴油等石油产品对细颗粒物污染的贡献,并提出了合理利用化石燃料减少细颗粒物污染的建议     

北京大气颗粒物特性的变化

对1985年以来用八级采样器采集、用PIXE分析法测得的部分元素浓度数据进行了分析,发现铅的粒径分布在这些年中发生了明显变化,这一变化反映了其来源的变化;硫的粒径分布一直呈现燃煤来源的特征;硅的粒径分布在尘暴前,远处尘暴到达时和本地尘暴起来时有明显的变化.     

气象条件对北京北郊冬季气溶胶污染的影响

对2004年1月1～12日北京大气物理所气象观测塔院内气溶胶浓度的观测资料和同期的气象资料进行了分析,结果表明北京冬季出现气溶胶污染的频率较高,采样期间超标率达58%,超标发生时地面风速较小,以偏东风为主,并伴有强的低空逆温;稳定性降雪过程对PM10有滞后的清除作用.气溶胶浓度与相对湿度和风速二元线性回归分析结果表明,平均风速对PM10日均浓度的影响较大,北京冬季PM10体现了细粒子的特征.天气形势对气溶胶浓度的影响显著,冬季当北京位于高压或两高压的均压场内,会出现地面高污染.     

呼和浩特市空气污染指数与气象要素的关系分析

根据呼和浩特市2000年6月至2011年3月的空气污染指数和同期的气象数据,分别对空气污染指数的年均值和月均值及其变化规律、空气质量级别及首要污染物等进行了统计分析,并分析探讨空气污染指数和气象要素之间的相关关系。结果表明:呼和浩特市空气质量正逐步变优,优良率已达95.6%;空气污染指数与气压和最大风速呈正相关关系,并与气温和降水量呈负相关关系。     

Relationship Between Biologically Fluorescent Aerosol and Local Meteorological Conditions

Time-resolved characterization of biological aerosol is important both for understanding environmental processes that affect biological aerosols and for determining realistic test conditions for the evaluation of bioaerosol detection systems. Very little work has been done to develop an understanding of the temporal fluctuations in bioaerosol concentration. During an experiment from 1–10 November 2008 ambient biological aerosol and meteorological data were collected. A FLIR/ICx/S3I Instantaneous Bioaerosol Analysis and Collection sensor was used to count both the biological and nonbiological aerosol in two size bins. The data indicate that the ambient relative humidity affects the optically observable concentration of biological aerosol with higher relative humidity generally associated with higher biological aerosol concentrations. The short timescale over which these correlations exist implies an aerosol process, rather than a change in aerosol source.

© 2013 American Association for Aerosol Research     

西安市可吸入颗粒物污染水平及其与气象条件的关系

分析了2001～2004年西安大气可吸入颗粒物(PM10)浓度的变化特征.结果显示,PM10浓度变化有明显的季节特征,冬季最高,春季次之,夏季最低,年平均浓度约为142 μg/m3,明显高于同时期广州的浓度(107 μg/m3).近5年的数据分析显示,PM10质量浓度总体呈下降趋势.西安地区PM10浓度与气象因素的分析显示,PM10浓度与湿度正相关,即浓度较高时,湿度相对较高,浓度较低时湿度相对也较低.PM10浓度还与风速和气压负相关.高浓度日的5 d后项气团轨迹分析显示,影响西安地区的气团有A,B,C,D 4条路径,其中路径B和C分别占到高浓度日的40%和45%,为主要传输路径.     

Reactions of Carbonaceous Smoke Particles with Atmospheric Ozone

Large quantities of carbonaceous smoke particles are expected to be lofted into the upper troposphere and lower stratosphere as a result of massive fires accompanying an exchange of nuclear explosions. These smoke particles can be expected to chemically react with various reactive species in the ambient atmosphere, thereby scavenging the smoke and affecting the balance of atmospheric chemistry. Of particular interest is the reaction of the smoke particles with ozone, because of the abundance of the latter relative to the amount of smoke assumed to be generated in various nuclear war scenarios. A laboratory apparatus has been constructed to examine the reaction of smoke particles with ozone. Smoke has been generated in a burner and collected from forest fires by airborne sampling. Buoyant smoke particles are passed into two parallel reactor tubes. These reactors differ by the presence or absence of ozone in the flow. The time course of the transmission of light through these two smoke columns provides a measure of the stability and reactivity of the smoke with and without ozone. Smoke particles are also deposited on sized filters for examination with the scanning electron microscope. Some results are reported on smoke particles collected from laboratory burner flames and from a prescribed forest fire in the Lodi Canyon, Los Angeles, CA.     

二氧化硫与大气颗粒物的复相反应研究

利用原位FTIR,XPS等手段研究了SO2与大气颗粒物及部分氧化物的复相反应,确认了表面反应产物,讨论了复相反应历程和表面反应机理.结果表明,SO2在大气颗粒物和氧化物表面发生吸收和氧化反应,表面产物为SO32-和SO42-.表面酸碱性是不同氧化物对SO2吸收和氧化能力有较大差异的主要原因,本实验条件下氧化物和大气颗粒物样品复相反应能力顺序为Al2O3＞CaO>>SiO2,Fe2O3,大气颗粒物样品.     

抚顺市大气颗粒物的研究进展

对近十年抚顺市PM10、PM2.5污染特征的研究结果进行总结,为了进一步全面研究PM2.5确定主要的污染源、各污染源的特征元素、PM2.5的样品成分。总结表明土壤尘、煤烟尘、尾气尘、工业尘、道路尘、有机碳是主要污染源,工业区、交通区、居民区和商业区是理想的采样点区域,理想的采样时间是按季节采样。     

Fluorochrome in Monitoring Atmospheric Bioaerosols and Correlations with Meteorological Factors and Air Pollutants

The characteristics of bioaerosols in the ambient atmosphere were monitored by using epifluorescence microscopy with fluorochrome (EFM/FL) with five fluorescent dyes (AO, DAPI, SYTO-13, PI, and YOPRO-1). The correlations of bioaerosols with meteorological factors and air pollutants were simultaneously assessed. Results from EFM/FL were then compared with those using a commonly used culture-based method. The total microbial cell concentrations measured by the non-culture-based methods averaged about 8 × 10⁵ cells/m³. However, culture-based method underestimated bioaerosol concentrations by the factor of 100 to 1000. The average viabilities were 0.66 by EFM/FL with PI staining, 0.35 with YOPRO-1 staining, and 0.0012 by the culture-based method. The viability by EFM/FL was much higher than the culturability. In summary, the total microbial cell concentration and viability were highly underestimated by the culture-based method. Moreover, based on culture-based and non-culture-based methods results, the total bioaerosol concentrations could be strongly correlated with a result of the temperature, rainfall, and UV light influence. However, there were weak correlations between bioaerosol concentrations and air pollutants. In conclusion, the intercomparisons of the total microbial cell concentration and viability of atmospheric bioaerosols were successfully assessed by EFM/FL and culture-based method. In addition, our study demonstrated that strong correlations between bioaerosols and meteorological factors by non-culture-based methods in atmospheric samples.