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1、X-RayFluorescenceanalysisAimoftheprojectToestablishthecontentandconcentrationofheavymetalsinsoilsamples.ThespecimensusedweretakenfromBulgaria.ThefirstsamplewasobtainedinPlovdiv,rightinthecenteroftown.Thesecond-fromafieldnearametalworks,locatedoutsideofPlovdiv.Thesamemethodcanbeusedtodeterminethequa
2、ntityofmicro-admixturesinobjectsofthesurroundingenvironment(e.g.minerals,ashesofplants,dryresiduaofwatersamples)EquipmentdescriptionThemulticomponentX-RayFluorescenceanalysisinvolvesdetectionandmeasurmentofthesecondaryemissionofx-raysbytheatomsoftheelementsinthespecimen.Theyarebeingexcitedbygammara
3、ysorx-raysofastandardradioactiveisotopesourcesuchasCd109(emanationenergyE=22,16keV,T1/2=453days)orAm241(E=59,57keV,T1/2=458y).Asemi-conductivesilicon/lithiumspectrometerisused,withanareaofabout30mm2andthicknessof3mm.Inthispictureyoucanseethepulse-heightanalyzerandtheanalysissoftwarebeingused:Canber
4、ra’sWinAxilandWinFund.AndthesearethetwosoilsamplestakenfromBulgaria.Thesoilneedstobedriedout.Bothsampleswereputinanovenfortwohoursatatemperatureof1050C.Afterwards,bothsoilspecimenswereground,putintocassettes,signedandweighedout,whichconcludedthepreparationofthesamples.Theothertypeofspecimenisactual
5、lyathinlayerofthesamesoil,bakedandground,andstuckonapieceoftape.Twokindsofsampleswereexamined.Inthefirstpictureyoucanseeapreparedsample,putonthesource.Itcontains2-3gofsoilputinacassette(saturatedlayerspecimen).Thespectraofthesoilsdisplaytheneedofhavingtwodifferenttypesofsamplepreparation:WinFund:Sp
6、ectrumofthesaturatedlayer,sample#1.Spectrumofthethinlayer,sample#1.Spectrumofthesaturatedlayer,sample#2.Spectrumofthethinlayer,sample#2.UsingCanberra’sWinaxil,thespectraareanalyzedfurther.Afittingmodelandthechemicalelementsofinterestareset,afterwards,theareaofeachpeakiscalculated.Spectrumofsample#1
7、,saturatedlayer:Spectrumofsample#2,saturatedlayer:CalibrationcurveswereusedtocalculatetheexactvaluesofSe,CrandNiconcentration.elementsconcentration[%]sample#1concentration[%]sample#2Pb<0,0040,045±0,004Ca2,3
