简介：PM_(1.0)(好粒子，与直径<1μm)，PM_(2.5)(好粒子，与直径<2.5μm)并且PM_(10)(粗糙的粒子，与直径<10μm)是在香港的一条高交通的道路附近的测量at24小时间隔，从2004年10月到2005年9月。Massconcentrations为三粒子部分被决定，平均为PM_(1.0)，PM_(2.5)和PM_(10)，分别地44.5±18.4，55.4±25.5和81.3±37.7μg·m~(-3)。PM_(2.5)是3.7times美国EPA“s15μg·m~的年度NAAQS(-3)。总的来说，PM_(1.0)占了44～69%(一般水准57%)PM_(10)，当PM_(2.5)占了58～82%时，(一般水准71%)在这学习。Theparticulate群众在冷季节与高集中显示出明显的季节的模式并且在温暖的季节低，PM_(2.5-10)的特别高的集中在冷季节期间。PM_(2.5)的集体集中的Diurnalvariations在7月期间是坚定的，证明二个学生在早上和下午上下班时间达到顶点。

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简介：Measurementsofparticulatematter(PM),i.e.,PM10,PM2.5,andPMl,havebeenperformedontheCantonTower,alandmarkbuildinginGuangzhou,atheightsof121and454msinceNovember2010,usingaGRIMM180aerosolparticlespectrometer(Germany).AnalysesofdatafromNovember2010toMay2013showedthattheannualaveragevaluesofPM10,PM2.5,andPMlattheobservationheightof121mabovethegroundwere44.1,38.2,and34.9μg/m3,respectively,andthoseat454mabovethegroundwere35.7,30.4,and27.5μg/m3,respectively.ByconsideringthevaluesofthesecondaryconcentrationlimitsgivenintheAmbientAirQualityStandardsissuedin2012,itwasobservedthattheannualaveragevaluesofPM10attheobservationheightsof121and454m,aswellasthoseofPM2.5at454m,reachedthosestandards.Furthermore,theover-standardamplitudeoftheannualaveragevalueofPM2.5attheobservationheightof121mwas9.1%.Duringtheobservationperiod,themaximumdailyaveragevaluesofPM10,PM2.5,andPM1attheobservationheightof121mwere183.3,144.8,and123.8μg/m~3,respectively,andthoseat454mwere102.8,92.7,and86.4μg/m3.ThedailyaveragevaluesofPM10attheobservationheightof454mwerenotabovethestandards.Theover-standardfrequenciesofthedailyaveragevaluesofPM10andPM2.5attheobservationheightof121mwere0.6%and10.7%,respectively,andtheover-standardamplitudeswere9.0%and24.4%,respectively.Theover-standardfrequencyofthedailyaveragevalueofPM2.5attheobservationheightof454mwas2.0%,andtheover-standardamplitudewas10.4%.Accordingly,itcanbestatedthattheairattheobservationheight454mabovethegrounddidnotreachthesecondarylimitofthenewstandards.Thepollutionwasmostseriousduringwinter,andtheairwasrelativelycleanerduringsummer.Overall,theverticaldistributionsofPM10,PM2.5,andPMldecreasedwithheight.Thelapseratesshowedthefollowingsequence:PM10>PM2.5>PM1,whichindicatesthattheverticaldistributionoffineparticles

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简介：ThisstudyinvestigatesthecorrelationbetweenPM10andmeteorologicalfactorssuchaswindspeed,atmosphericvisibility,dewpoint,relativehumidity,andambienttemperatureduringabrownhazeepisode.InordertoidentifythepotentialsourcesofPM10duringbrownhazeepisode,respirableparticulatematter(PM10)wascollectedduringbothnon-hazedaysandhazedaysandfurtheranalyzedformetallicelements,ionicspecies,andcarbonaceouscontents.Amongthem,ionicspeciescontributed45-64%toPM10,whilemetallicelementscontributed7-21%toPM10whichwassmallerthantheotherchemicalconstituents.TheaverageOC/ECratio(42)inhazedayswasaboutthreetimesoftheaverageOC/ECratio(14)innon-hazedays.Byusingchemicalmassbalance(CMB)receptormodel,themajorsourceswereapportioned,includingtraffics,incinerators,coalcombustion,steelindustry,petrochemicalindustry,andsecondaryaerosols,etc.ThecontributiontoPM10concentrationofeachsourcewascalculatedforallthesamplescollected.TheresultsshowedthatcoalcombustionwasthemajorsourceofPM10innon-hazedaysandsecondaryaerosolswerethemajorsourceinhazedays,followedbypetrochemicalindustry,incinerators,andtraffics,whileothersourceshadnegligibleeffect.

简介：在西安，长期的变化和关系从2001-2004基于从1980-2002获得的每日的可见性数据和空气污染索引数据因为每天水平的扑灭系数和PM_(10)的集体集中被评估了。一个减少的趋势在过去的23年期间在水平扑灭系数被发现，与更高的价值相对1990年代的观察in1980s，和在冬季和夏天的最高、最低的价值分别地。重要关联和类似的季节的变化在水平扑灭系数和PM_(10)集中之间存在，建议到在在在过去的二十年期间的华中的Guanzhong平原的一个地点的可见性落下的PM_(10)的高影响。

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