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西安PM_(2.5)碳组成及水溶性有机物分子特性和来源季节差异
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作者 杨毅 赵明佳 +1 位作者 张亚楠 刘伟 《安全与环境学报》 CAS CSCD 北大核心 2024年第7期2860-2868,共9页
利用平行因子分析和后向轨迹模型,采用紫外光谱法、三维荧光光谱法,分析西安市PM_(2.5)碳组成及水溶性有机物(Water-Soluble Organic Matters,WSOM)的荧光组分、分子特性和来源。结果显示,西安市各季节PM_(2.5)及其有机碳(Organic Carbo... 利用平行因子分析和后向轨迹模型,采用紫外光谱法、三维荧光光谱法,分析西安市PM_(2.5)碳组成及水溶性有机物(Water-Soluble Organic Matters,WSOM)的荧光组分、分子特性和来源。结果显示,西安市各季节PM_(2.5)及其有机碳(Organic Carbon,OC)和元素碳(Elemental Carbon,EC)的质量浓度由高到低依次为:冬、秋、春、夏,且南北郊差异不显著。PM_(2.5)中水溶性有机碳(Water-Soluble Organic Carbon,WSOC)质量浓度为3.50~17.29μg/m^(3),冬季WSOC质量浓度最高。四季的WSOM中均含有紫外光类腐殖质和可见光类腐殖质。秋、冬和夏季类富里酸的荧光强度占比最大。WSOM的E_(2)/E_(3)、E_(3)/E_(4)和AAE值由高到低依次是:冬、春、夏、秋。SUVA 254和MAE_(3)65值均在冬季最高,夏季最低。冬季WSOM的相对分子质量和腐殖化程度较小,分子苯环取代程度最大,光吸收能力对光吸收的波长依赖性较强;秋季WSOM的相对分子质量较大,腐殖化程度较强,光吸收的波长依赖性较弱;夏季WSOM的芳香化程度和光吸收能力及春季WSOM分子苯环取代程度最弱。碳组分质量浓度、UV 254、α350和荧光强度两两呈显著正相关(p<0.01)。WSOM的荧光指数(Fluorescence Index,FI)、生物源指数(Biogenic Index,BIX)和腐殖化指数(Humification Index,HIX)值分别为1.51~2.15、0.88~1.46、1.18~3.19。冬季WSOM的自生来源最高,夏季WSOM的陆源来源比例相对较大。西安市污染气团主要来自于陕西省区域气团传输。西安市四季PM_(2.5)碳组成及WSOM的荧光组分、分子特性和来源存在季节差异,但北郊和南郊的紫外荧光光谱特性和来源差异不显著。 展开更多
关键词 环境学 PM_(2.5) 水溶性有机物(wsom) 荧光特性 平行因子分析 来源
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Development of an on-line measurement system for water-soluble organic matter in PM_(2.5) and its application in China 被引量:5
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作者 Huiying Li Xiaofeng Huang +3 位作者 Liming Cao Yuhong Zhai Liwu Zeng Lingyan He 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2018年第7期33-40,共8页
Water-soluble organic matter(WSOM) represents a critical fraction of fine particles(PM2.5)in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast... Water-soluble organic matter(WSOM) represents a critical fraction of fine particles(PM2.5)in the air, but its changing behaviors and formation mechanisms are not well understood yet, partly due to the lack of fast techniques for the ambient measurements. In this study,a novel system for the on-line measurement of water-soluble components in PM2.5, the particle-into-liquid sampler(PILS)–Nebulizer–aerosol chemical speciation monitor(ACSM), was developed by combining a PILS, a nebulizer, and an ACSM. High time resolution concentrations of WSOM, sulfate, nitrate, ammonium, and chloride, as well as mass spectra, can be obtained with satisfied quality control results. The system was firstly applied in China for field measurement of WSOM. The mass spectrum of WSOM was found to resemble that of oxygenated organic aerosol, and WSOM agreed well with secondary inorganic ions. All evidence collected in the field campaign demonstrated that WSOM could be a good surrogate of secondary organic aerosol(SOA). The PILS–Nebulizer–ACSM system can thus be a useful tool for intensive study of WSOM and SOA in PM2.5. 展开更多
关键词 PM2.5 water-soluble organic matter Secondary organic matter On-line measurement Mass spectrum
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红树林湿地沉积物中WSOM与Cu^(2+)的络合特性研究
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作者 罗艺璇 甘义群 《安全与环境工程》 CAS CSCD 北大核心 2022年第5期139-147,共9页
水溶性有机质(WSOM)与重金属络合可以控制重金属的固定和释放过程,从而影响重金属在环境中的毒性。通过提取海口市东寨港红树林湿地根际区、红树区和光滩区3个区域沉积物中的WSOM,与Cu^(2+)进行室内络合试验,以荧光光谱为表征手段,并结... 水溶性有机质(WSOM)与重金属络合可以控制重金属的固定和释放过程,从而影响重金属在环境中的毒性。通过提取海口市东寨港红树林湿地根际区、红树区和光滩区3个区域沉积物中的WSOM,与Cu^(2+)进行室内络合试验,以荧光光谱为表征手段,并结合多种分析方法,研究了东寨港红树林湿地3个区域沉积物中WSOM与Cu^(2+)的络合特性。结果表明:(1)东寨港红树林湿地沉积物中WSOM的组成在3个区域内具有显著的差异,根际区以类蛋白质为主要组分,红树区和光滩区则以类腐殖质为主要组分;(2)3个区域沉积物中,色氨酸类WSOM更易于与Cu^(2+)结合,类腐殖质组分比类蛋白质组分形成的络合物具有更好的稳定性;(3)根际活动并没有明显加强WSOM对Cu^(2+)的络合作用,根际区重金属含量较高是由于根际沉积物中整体WSOM的含量高。 展开更多
关键词 红树林湿地 沉积物 水溶性有机质(wsom) 铜离子(Cu^(2+)) 荧光光谱 荧光猝灭
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PM_(2.5)中水溶性有机物吸光特性的模拟研究 被引量:8
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作者 吴一凡 黄晓锋 +3 位作者 兰紫娟 宫照恒 云慧 何凌燕 《中国环境科学》 EI CAS CSCD 北大核心 2013年第10期1736-1740,共5页
研究建立了超声雾化器与光声光谱仪,扫描电迁移率颗粒物粒径谱仪联用的分析系统,将深圳市2011年夏季采集的PM2.5膜样品提取液雾化发生气溶胶,使之进入光声光谱仪检测其吸光强度以研究气溶胶中水溶性有机物(WSOM)的吸光特征.结果表明:观... 研究建立了超声雾化器与光声光谱仪,扫描电迁移率颗粒物粒径谱仪联用的分析系统,将深圳市2011年夏季采集的PM2.5膜样品提取液雾化发生气溶胶,使之进入光声光谱仪检测其吸光强度以研究气溶胶中水溶性有机物(WSOM)的吸光特征.结果表明:观测期间PM2.5中WSOM平均质量浓度为(4.3±2.3)μg/m3,分别占PM2.5和OM质量浓度的11.9%±4.8%和49.2%±18.5%.WSOM在405,532,781nm波长下的质量吸收效率值(MAE)分别为(0.55±0.31),(0.54±0.31),(0.21±0.13)m2/g.经计算所得:深圳市夏季大气PM2.5中WSOM在405,532,781nm波长下的平均吸收系数分别为(2.30±1.08),(2.25±1.26),(0.86±0.45)Mm-1,对应的WSOM对大气PM2.5整体吸光效应的贡献率分别为7.6%,10.6%和5.8%,说明WSOM对PM2.5整体吸光效应的贡献不容忽视,有机气溶胶在大气灰霾中的能见度损害作用值得进一步深入研究. 展开更多
关键词 光声光谱仪 水溶性有机物(wsom) 吸光系数 质量吸收效率(MAE)
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Sensitivity of Labile Soil Organic Carbon Pools to Long-Term Fertilizer, Straw and Manure Management in Rice-Wheat System 被引量:20
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作者 Dinesh K.BENBI Kiranvir BRAR +1 位作者 Amardeep S.TOOR Shivani SHARMA 《Pedosphere》 SCIE CAS CSCD 2015年第4期534-545,共12页
Labile soil organic carbon (SOC) pools, estimated through chemical fractionation techniques, are considered sensitive indicators of management-induced changes in quality and composition of soil organic matter. Altho... Labile soil organic carbon (SOC) pools, estimated through chemical fractionation techniques, are considered sensitive indicators of management-induced changes in quality and composition of soil organic matter. Although the impacts of organic manure and crop residue applications on C sequestration in rice-wheat system are fairly well documented, their influence on labile SOC pools is relatively less known. Impacts of organic manure, rice straw, and inorganic fertilizer nitrogen (N) applications on soil total organic carbon (TOC) and SOC pools including water-extractable organic C (WEOC), hot water-soluble organic C (HWOC), potassium permanganate- oxidizable organic C (KMnO4-C), microbial biomass C (MBC), mineralizable organic C (Cmin), and the oxidizable fractions of decreasing oxidizability (easily-oxidizable, oxidizable, and weakly-oxidizable) were investigated in an ll-year field experiment under rice-wheat system. The field experiment included treatments of different combinations of farmyard manure, rice straw, and fertilizer N application rates, with C inputs estimated to be in the range from 23 to 127 Mg ha-1. After 11 years of experiment, WEOC, HWOC, and KMnO4-C were 0.32%-0.50%, 2.2%-3.3%, and 15.0%-20.6% of TOC, respectively. The easily-oxidizable, oxidizable, and weakly-oxidizable fractions were 43%-57%0, 22%-27%, and 10%-19% of TOC, respectively. The applications of farmyard manure and rice straw improved WEOC, HWOC, KMnO4-C, easily-oxidizable fraction, Cmin, and MBC, though the rates of change varied considerably from -14% to 145% and -1170 to 83% of TOC, respectively. At the C input levels between 29 and 78 Mg C ha-1 during the ll-year period, the greatest increase was observed in WEOC and the minimum in KMnO4-C. Water-extractable organic C exhibited a relatively greater sensitivity to management than TOC, suggesting that it may be used as a sensitive indicator of management-induced changes in soil organic matter under rice-wheat system. All the other labile SOC pools exhibited almost the same sensitivity to management as TOC. Most of the SOC pools investigated were positively correlated to each other though their amounts differed considerably. Long-term applications of farmyard manure and rice straw resulted in build-up of not only the labile but also the recalcitrant pool of SOC, emphasizing the need for continued application of organic amendments for permanence of the accrued C under the experimental conditions. 展开更多
关键词 metabolic quotient mineralizable C organic amendments oxidizable C soil microbial biomass soil organic matter water-soluble C
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深圳大气PM2.5中水溶性有机物的来源特征 被引量:1
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作者 孙逸飞 李孟林 +4 位作者 江家豪 戴静 高茂尚 黄晓锋 何凌燕 《中国环境科学》 EI CAS CSCD 北大核心 2020年第5期1869-1876,共8页
对2017年9月~2018年8月深圳市北部大气PM2.5中水溶性有机物(WSOM)的质量浓度、质谱及来源结构进行测量和分析.结果表明:PM2.5的质量浓度为(32.3±18.4)μg/m^3,WSOM的质量浓度为(9.4±5.7)μg/m^3,占颗粒物总有机物的(77.6%... 对2017年9月~2018年8月深圳市北部大气PM2.5中水溶性有机物(WSOM)的质量浓度、质谱及来源结构进行测量和分析.结果表明:PM2.5的质量浓度为(32.3±18.4)μg/m^3,WSOM的质量浓度为(9.4±5.7)μg/m^3,占颗粒物总有机物的(77.6%±14.0%).质谱分析显示,WSOM的氧碳比(O/C)平均值达到(0.57±0.09),属于二次有机物的O/C值范围,且生物质燃烧排放的离子碎片C2H4O^2+的丰度显著,说明WSOM的来源中有显著的生物质燃烧排放的有机气溶胶.为了明确WSOM的来源结构,利用正矩阵因子分解法(PMF)模型进行来源解析,发现3个合理因子:高氧化态有机气溶胶(MO-OOA),低氧化态有机气溶胶(LO-OOA)和生物质燃烧(BBOA),贡献比例分别为51.7%,31.8%和16.5%.MO-OOA和BBOA贡献浓度均呈现秋冬高、春夏低的季节变化特征,反向轨迹分析显示其与内陆污染传输关系密切.LO-OOA的变化相对稳定,本地源的贡献较大.结合14C同位素示踪法对秋冬季WSOM样品分析,发现机动车等化石源二次有机物是WSOM的主要来源,贡献比例达到53.9%,需继续加强对化石燃料控制来降低WSOM污染. 展开更多
关键词 水溶性有机物(wsom) 正矩阵因子分解法(PMF) 14C同位素 来源分析
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太湖草、藻湖区沉积物WSOM组成和分子结构分析 被引量:3
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作者 杜瑛珣 戴家如 +4 位作者 张巧颖 刘静静 黄秀琳 安世林 文帅龙 《环境科学》 EI CAS CSCD 北大核心 2022年第8期4108-4117,共10页
草型湖泊(区)和藻型湖泊(区)是浅水湖泊的两种典型状态,两种湖泊中有机质(OM)的来源和转化存在明显差异.有机质在沉积物上的埋藏是湖泊碳汇功能的重要体现.沉积物中的有机质可能发生后续的转化,影响湖泊碳汇功能;其转化过程与其固有的... 草型湖泊(区)和藻型湖泊(区)是浅水湖泊的两种典型状态,两种湖泊中有机质(OM)的来源和转化存在明显差异.有机质在沉积物上的埋藏是湖泊碳汇功能的重要体现.沉积物中的有机质可能发生后续的转化,影响湖泊碳汇功能;其转化过程与其固有的性质密切相关.目前为止,有关草型和藻型湖泊沉积物中有机质的组成,特别是分子结构差异的信息较少.为此,采集太湖草型湖区(东太湖)和藻型湖区(梅梁湾)沉积物,提取和纯化沉积物中的水溶性有机质(分别记为M-WSOM和A-WSOM),并采用紫外-可见吸收光谱、三维荧光光谱、傅立叶红外光谱和傅里叶变换-离子回旋共振-质谱(FT-ICR MS)对WSOM性质组成和分子结构进行详尽的表征与分析.结果表明:(1)M-WSOM的相对分子质量比A-WSOM的(E_(2)∶E_(3)指标)稍大;FT-ICR MS的数据显示,M-WSOM和A-WSOM的相对分子质量分别为388.9和379.9.(2)M-WSOM的芳香性略高于A-WSOM的(SUVA_(254)和HIX指标);同样地,FT-ICR MS的结果显示,M-WSOM中稠环芳烃(6.3%,强度加权平均占比,下同)、芳香类物质(7.7%)的含量高于A-WSOM(分别为1.1%和4.4%);(3)荧光组分结果表明A-WSOM中类蛋白质组分的含量大于M-WSOM;FT-ICR MS的结果与之对应,A-WSOM的多肽含量(35.5%)高于M-WSOM的(15.6%);(4)质谱数据显示了高分辨的分子信息:M-WSOM和A-WSOM中,沉积物中含杂原子的分子分别占82.9%和91.7%;其中含氮元素的分子占比高达53.5%和78.5%;含磷元素分子占30.4%和41.4%,M-WSOM磷元素主要分布在脂肪烃和高度不饱和低氧物质中,而A-WSOM则主要分布在多肽中.揭示了浅水湖泊两种典型状态沉积物OM的组成和分子结构;有助于研究湖泊沉积物的温室气体排放,及碳、氮、磷元素的生物地球化学过程. 展开更多
关键词 吸收光谱 三维荧光光谱 红外光谱 傅里叶变换-离子回旋质谱 水溶性有机质(wsom)
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西安冬季PM_(2.5)中不同极性水溶性有机物的污染特征及氧化潜势 被引量:2
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作者 罗玉 黄沙沙 +2 位作者 张甜 孙健 沈振兴 《环境科学》 EI CAS CSCD 北大核心 2023年第4期1882-1889,共8页
大气细颗粒物(PM_(2.5))通过产生活性氧(ROS)对健康造成不利影响.酸性、中性和高极性水溶性有机物(WSOM)是有机气溶胶中产生ROS的重要成分.采集西安市区2019年冬季PM_(2.5)样品,深入探究不同极性水平WSOM组分的污染特征和健康风险.结果... 大气细颗粒物(PM_(2.5))通过产生活性氧(ROS)对健康造成不利影响.酸性、中性和高极性水溶性有机物(WSOM)是有机气溶胶中产生ROS的重要成分.采集西安市区2019年冬季PM_(2.5)样品,深入探究不同极性水平WSOM组分的污染特征和健康风险.结果表明,西安市PM_(2.5)中ρ(WSOM)为(4.62±1.89)μg·m^(-3),类腐殖质物质(HULIS)是WSOM的重要组成部分(78.81%±10.50%),霾天HULIS的占比更高.三类不同极性WSOM的碳浓度水平在霾天和非霾天大小分别为:中性HULIS(HULIS-n)>酸性HULIS(HULIS-a)>高极性有机物(HP-WSOM)和HULIS-n>HP-WSOM>HULIS-a.采用DCFH(2′,7′-二氯二氢荧光素)法测量其氧化潜势(OP),发现霾天和非霾天单位质量OP(OPm)的规律均为HP-WSOM>HULIS-a>HULIS-n,单位空气体积OP(OPv)特征为:HP-WSOM>HULIS-n>HULIS-a.整个采样期间OPm与WSOM的三类组分碳浓度呈负相关.霾天HULIS-n(R2=0.866 9)和HP-WSOM(R2=0.858 2)的OPm与其碳浓度高度相关,非霾天HULIS-n、 HULIS-a和HP-WSOM的OPm对各碳浓度都有很强的依赖性. 展开更多
关键词 水溶性有机物(wsom) 类腐殖质(HULIS) 氧化潜势(OP) 活性氧(ROS) 碳浓度
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不同离子条件对提取沉积物中水溶性有机质光谱特性的影响 被引量:1
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作者 晏彩霞 文鑫梅 +5 位作者 杨雪 陈洁 李倩 罗紫薇 丁聪 聂明华 《环境科学学报》 CAS CSCD 北大核心 2019年第11期3866-3876,共11页
水溶性有机质(WSOM)是环境中溶解性有机质(DOM)的重要组成部分,对WSOM化学特性的研究有助于了解环境中DOM对污染物环境归趋的作用.本文利用紫外-可见吸收光谱法(UV-vis)及三维荧光光谱法(3D-EEM)分析了3种不同来源沉积物的WSOM在不同种... 水溶性有机质(WSOM)是环境中溶解性有机质(DOM)的重要组成部分,对WSOM化学特性的研究有助于了解环境中DOM对污染物环境归趋的作用.本文利用紫外-可见吸收光谱法(UV-vis)及三维荧光光谱法(3D-EEM)分析了3种不同来源沉积物的WSOM在不同种类及浓度离子浸提液中的光谱特性差异,以揭示天然水化学离子种类及浓度对提取沉积物中WSOM光谱特性的影响.UV-vis光谱分析结果表明:①WSOM在SO4^2-及K^+浸提液中的溶解性有机碳(DOC)含量及其芳香度较高,在Cl^-及K^+浸提液中的有色溶解性有机质(CDOM)丰度高,在NO3^-、Na^+浸提液中的富里酸含量较高、分子量较小;②浸提液中WSOM的DOC含量及其芳香度、CDOM丰度随离子浓度增加呈先增后减的趋势,同时大颗粒WSOM比例逐渐增加.通过3D-EEM光谱数据结合平行因子分析法发现,沉积物(城市内湖)中WSOM主要由4种荧光组分组成,即可见腐殖酸(C1)、土壤富里酸(C2和C3)、微生物源类腐殖质(C4).4种荧光组分在SO4^2-、K^+浸提液中的荧光强度较高,且随离子浓度增加WSOM的荧光强度、类蛋白物质及类腐殖物质浓度均表现为高浓度受抑制的现象,这一点与吸收光谱数据一致. 展开更多
关键词 水溶性有机质(wsom) 沉积物 紫外 可见吸收光谱 三维荧光光谱(3D EEM) 化学离子
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Atmospheric fine particles in a typical coastal port of Yangtze River Delta 被引量:4
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作者 Qi Yuan Xiaomi Teng +10 位作者 Shaoxuan Tu Binxin Feng Zhiyu Wu Hang Xiao Qiuliang Cai Yinxiao Zhang Qiuhan Lin Zhaoce Liu Mengmeng He Xiaokun Ding Weijun Li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第12期62-70,共9页
In recent decades, coastal ports have experienced rapid development and become an important economic and ecological hub in China. Atmospheric particle is a research hotspot in atmospheric environmental sciences in inl... In recent decades, coastal ports have experienced rapid development and become an important economic and ecological hub in China. Atmospheric particle is a research hotspot in atmospheric environmental sciences in inland regions. However, few studies on the atmospheric particle were conducted in coastal port areas in China, which indeed suffers atmospheric particle pollution. Lack of the physicochemical characteristics of fine particles serves as an obstacle toward the accurate control for air pollution in the coastal port area in China. Here, a field observation was conducted in an important coastal port city in Yangtze River Delta from March 6 to March 19, 2019. The average PM2.5 concentration was 63.7 ±27.8 μg/m^3 and NO3^-, SO4^2-, NH4^+, and organic matter accounted for ?60% of PM 2.5. Fe was the most abundant trace metal element and V as the ship emission indicator was detected. Transmission electron microscopy images showed that SK-rich, soot, Fe, SK-soot and SK-Fe were the major individual particles in the coastal port. V and soluble Fe were detected in sulfate coating of SK-Fe particles. We found that anthropogenic emissions, marine sea salt, and secondary atmosphere process were the major sources of fine particles. Backward trajectory analysis indicated that the dominant air masses were marine air mass, inland air mass from northern Zhejiang and inland-marine mixed air mass from Shandong and Shanghai during the sampling period. The findings can help us better understand the physicochemical properties of atmospheric fine particles in the coastal port of Eastern China. 展开更多
关键词 Coastal port water-soluble ion organic matter Trace metal Individual particle
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Chemical composition of PM_(2.5) during winter in Tianjin,China 被引量:61
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作者 Jinxia Gu Zhipeng Bai +4 位作者 Weifang Li Liping Wu Aixia Liu Haiyan Dong Yiyang Xie 《Particuology》 SCIE EI CAS CSCD 2011年第3期215-221,共7页
PM2.5 samples for 24h were collected during winter in Tianjin, China. The ambient mass concentration and chemical composition of the PM2.5 were determined. Ionic species were analyzed by ion chromatography, while carb... PM2.5 samples for 24h were collected during winter in Tianjin, China. The ambient mass concentration and chemical composition of the PM2.5 were determined. Ionic species were analyzed by ion chromatography, while carbonaceous species were determined with the IMPROVE thermal optical reflectance (TOR) method, and inorganic elements were measured by inductively coupled plasma-atomic emission spectrometer. The daily PM2.5 mass concentrations ranged from 48.2 to 319.2 μg/m^3 with an arithmetic average of 144.6 μg/m^3. The elevated PM2.5 in winter was mostly attributed to combustion sources such as vehicle exhaust, heating, cooking and industrial emissions, low wind speeds and high relative humidity (RH), which were favorable for pollutant accumulation and formation of secondary pollutants. By chemical mass balance, it was estimated that about 89.1% of the PM2.5 mass concentrations were explained by carbonaceous species, secondary particles, crustal matters, sea salt and trace elements. Organic material was the largest contributor, accounting for about 32.7% of the total PM2.5 mass concentrations. SO4^2-, NO3^-, Cl^- and NH4^+ were four major ions, accounting for 16.6%, 11.5%, 4.7% and 6,0%, respectively, of the total mass of PM2.5. 展开更多
关键词 PM2.5 water-soluble ions organic carbon (OC) Elemental carbon (EC) Crustal matter
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