???????

???? ????????

????? ??????? ????? ??? ???? ?? ????? ????? ?? ??? ?????? ?? ????? ???????? TiO2 ?? ????? ???? ???? ????? ???? ??? ????

5610 ???? ???? ??? ?????? ????? ???? ???? ???? ??????? ????? ??????? ?? ?????? ???????? ????? ????? ??????? ?? ????? ????? ????? ?? ???? ???? ???? ?????? ?? ????? ????? ??? ? ???? ?? 250 ???? 1 ???? ?????? ????? ?? 250 ???? ????? ????? ?? ??? ??????? ??? ? ????? ????? ?? ???? ?? ????? ??? ??? ???? ??? ????? ?? ????? ?? ??? ?? ???? 3000 ?

?????? ????? ??????? ????? ??? ???? ?? ????? ?????  ?? ??? ?????? ?? ????? ???????? TiO2 ?? ????? ???? ???? ????? ???? ??? ????

?????? ????? ??????? ????? ??? ???? ?? ????? ?????  ?? ??? ?????? ?? ???????? TiO2 ?? ????? ???? ???? ????? ???? ??? ????
???? ???? ????? ??
???? ???? docx
??? ???? 300 ???? ????
????? ????? ???? 22

????? ?????

?????

?????? ?? ??????? ??? ???? ????? ????? ????? ????? ?? ?????? (USA DMSPE)? ?? ??????? ?? ???????? TiO2 (NPS) ?? ????? ????? ?? ??? ??? ??? ???? ???? ??? (CV AAS) ???? ???­????? ? ????? ???? ???? (Hgtotal ? +Hg2 ? +CH3Hg) ?? ????? ??? ?????????? ????­????? ? ?? ??????? ??. ?????????? ????? ???? ????? ???????? TiO2 ? pH ????? ?????? ????? ?????? ? ???? ?????????? ?????­???? ????? ????? TiO2 ??? ?? ????? ?? CV AAS ???? ????? ???? ????. ??? ????? ???? ???? ?? 10 ????­???  TiO2 ?? pH  7.5 ?? ??? ???. ?? ?? ???????? ???? ?? ?????? ?? 500 ????????? HNO3 1 ??? ???? ????? ???? ????? ????? ????? ??. ?? ???? ?????? 0.004 ??????? ?? ????­???? ???? +Hg2 ???. ???? ??? ????? ?? ??? ???? 35 ???. ?????? ????????? ???? (RSDs??) ???? ????­??? ???? ?? ?????­??? ????? 4-20% ???. ??? ??? ??? ???? ?????? ???? ???? ????? ??? ??????? ?? DOLT-2  (??? ?? ????)? IAEA-085  (??? ?????)? SRM 2709  (??? ?? ??????)? SRM 2711 (??? ???????) ? SRM 2704  (?? ???? ??????? ??????). ?????? ???? ???? ??????­???? ??? ?? ???? ???? ?? ????? ????? ??? ?? ????? ????? (?? ???? ?? ????? t ???? ?? ??? ??????? 95?) ???. ??? ????? ??? ??? ?? ?????? ???? ????? ????­??? ???? ?? ?????­??? ?? ????? (?????? ?? ? ?? ???????) ????? ??.

a b s t r a c t
The combinationofultrasound-assisteddispersivemicrosolid-phaseextraction(USADMSPE),withthe
use ofTiO2 nanoparticles (NPs)asadsorbent,withcoldvaporatomicabsorptionspectrometry(CVAAS)is
proposed forpreconcentrationanddeterminationofmercuryspecies(Hgtotal, Hg2 and CH3Hg) in
biological, geologicalandwatersamples.TheexperimentalparametersincludingtheamountofTiO2 NPs,
pH ofsamplesolution,ultrasonicationandcentrifugationtime,TiO2 slurry solutionpreparationbefore
injection toCVAASwereinvestigated.Effectivepreconcentrationoftracemercurywith10mgofTiO2
wasachievedinpH7.5.Afterextraction,adsorbentwithanalyteswasmixedwith500 ?L of1molL1
HNO3 to prepareslurrysolution.Theconcentrationlimitofdetectionwas0.004ngmL1 for Hg2. The
achieved preconcentrationfactorwas35.Therelativestandarddeviations(RSDs,%)formercuryspecies
in realsampleswere420%. Theaccuracyofthismethodwasevaluatedbyanalysesofcertified reference
materials: DOLT-2(Dogfish Liver),IAEA-085(Humanhair),SRM2709(SanJoaquinSoil),SRM2711
(Montana Soil)andSRM2704(BuffaloRiverSediment).Themeasuredmercuryspeciescontentsinre-
ference materialswereinsatisfactoryagreementwiththeaddedamounts(accordingtothe t-test fora
95% confidence level).Thepresentedmethodhasbeensuccessfullyappliedforthedeterminationof
mercury speciesinrealwatersamples(lakeandriverwater).

?????? ????? ??????? ????? ??? ???? ?? ????? ?????  ?? ??? ?????? ?? ????? ???????? TiO2 ?? ????? ???? ???? ????? ???? ??? ????

?????? ????? : 1 2 3 4 5 6 | ?????? : 4
????? : | ?????? : 42
????? ?? : ????? ??????? ????? ??? ???? ?? ????? ????? ?? ??? ?????? ?? ????? ???????? TiO2 ?? ????? ???? ???? ????? ???? ??? ???? ,
+ ????? ??? ?? سه شنبه 19 دی 1396???? 13:27 ???? ???? |

??????? ????
?? ???? ?????
????? ???? ??????
????? ???? ??????