atomic absorption spectrometer n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
ATOMIC ABSORPTION SPECTROMETER PowerPoint Presentation
Download Presentation
ATOMIC ABSORPTION SPECTROMETER

Loading in 2 Seconds...

play fullscreen
1 / 28

ATOMIC ABSORPTION SPECTROMETER - PowerPoint PPT Presentation


  • 172 Views
  • Uploaded on

ATOMIC ABSORPTION SPECTROMETER. SELİN CANSU ÖZTÜRK ŞEYMA ATAKUL SEZİN GÜNER. ATOMIC ABSORPTION SPECTROMETER. Introduction Invention Working Principle of AAS Instrumentation Interferences & Correlation Methods Applications. INVENTION.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

ATOMIC ABSORPTION SPECTROMETER


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
    Presentation Transcript
    1. ATOMIC ABSORPTION SPECTROMETER SELİN CANSU ÖZTÜRK ŞEYMA ATAKUL SEZİN GÜNER

    2. ATOMIC ABSORPTION SPECTROMETER • Introduction • Invention • WorkingPrincipleof AAS • Instrumentation • Interferences & CorrelationMethods • Applications

    3. INVENTION • Introduced in 1955 by Alan Walsh in Australia • Firstlyusedformining, medicaltreatment&agriculture • Alan Walsh(1916-1998) http://www.science.org.au/academy/memoirs/walsh2.html

    4. PROPERTIES OF AAS • Themostwidelyusedmethod in analysis of elements • Based on theabsorption of radiation • Sosensitive (ppb) • Quantitativeanalysis

    5. WORKING PRINCIPLE OF AAS • Electronspromotetohigherorbitalsfor a shortamount of time byabsorbing a energy • M + hv →M* • Relises on Beer-Lambert Law A= a.b.c

    6. INSTRUMENTATION www.scientificlib.com

    7. LIGHT SOURCES HollowCathodeLamps • Anot-Tungsten wire • Cathodemadefromthe element of interest (Na,K,Ca..) • Argon or neon gas http://www.safir.be/AAS.ht

    8. LIGHT SOURCES ElectrodelessDischargeLamp • Typically argon gas at lowpressure • Narrowerlinewidth • Not prefered www.freepatentsonline.com

    9. ATOMIZATION • Compoundsmakingupthesamplearebrokenintofreeatoms. • High temperature is necessary • Basic twotypes -Flameatomizer -Electrothermalatomizer

    10. TYPES OF ATOMIZERS FLAME ATOMIZER • Simplestatomization • Convertsanalyteintofreeatoms of vaporphase • Flammable &causticgases • Not has an inertmedium(−) • Shortanalysis time (−)

    11. TYPES OF ATOMIZERS ELECTROTHERMAL ATOMIZER • A cylindiricalgraphitetube • Inertgasmedium (Argon gas) • Longeranlaysis time thanflame • Superiorsensitivity, highaccuracy

    12. MONOCHROMATOR • Alsoit is calledwavelenghselector • Select thespecificwavelenght • Polychromaticlight →monochromaticlight • Simple one is enoughfor AAS

    13. DETECTOR • Electromagneticwaves→ electriccurrent • ThemostusedonePhotomultipliertube • Havefastresponsetimes www.answers.com

    14. CALIBRATION TECHNIQUES • Two main techniques • Calibrationcurvemethod • Standart additionmethod

    15. CALIBRATION TECHNIQUES CALIBRATION CURVE METHOD • Draw a graph • Havetwoormorevariables -One is set at knownvalues -One is measuredresponse • Most convenient fora large number of similar samplesanalysis.

    16. CALIBRATION TECHNIQUES An example of calibrationcurvemethod

    17. CALIBRATIONTECHNIQUES STANDART ADDITION METHOD • To measure the analyte concentration in a complexmatrix. • Most convenient for small number of samplesanalysis • Preventeffect of chemical & spectralinterferences

    18. INTERFERENCES • Causes higherorlowerabsorbancevalue • Twomajorgroups • ChemicalInterferences • SpectralInterferences

    19. CHEMICAL INTERFERENCES • Themostcommonone in flameatomizer. • Consequence of chemicalreactions. • Reduceamount of oxygen in flametoovercome

    20. SPECTRAL INTERFERENCES • Absorptionoremission of theradiation at thesamewavelength • Radiationwhich is absorbed→pozitiveerrors • Radiationwhich is emmitted→negativeerrors

    21. SPECTRAL CORRELATION METHODS TWO-LINE CORRELATION METHOD • Select twoline • characteristicwavelength of analyte • veryclosetoanalyteline but not absorbedbyanalyte • Measurethedifferencebetweentwolines

    22. SPECTRAL CORRELATION METHODS CONTINUUM SOURCE CORRELATION METHOD • Select twolamps • Deuteriumlamp & hollowcathodelamp • Whenhollowcathodelamp is used total absorbace is measured • Whendeuteriumlamp is usedonly background absorption is measured • Measurethedifferencebetweentwolines.

    23. SPECTRAL CORRELATION METHODS ZEEMAN EFFECT CORRELATION METHOD • Presence of magneticfield. • Splitting of spectrallines.

    24. CONCLUSION • One of themostimportanttechnique in quantitativeanalysis • It is based on theabsorption of radiation • Measurementscould be done at ppblevels • It’swidelyusedmethod • Thepreparation of thesample is usuallysimpleandrapid

    25. CONCLUSION • Therearemanyadventages • High sensitivity [10-10 g (flame), 10-14 g (non-flame)] • Goodaccuracy (Relativeerror 0.1 ~ 0.5 % ) • Highselectivity

    26. APPLICATIONS OF AAS • Water analysis (e.g. Ca, Mg, Fe, Si, Al, Ba content) • Foodanalysis • Analysis of animal feedstuffs (e.g. Mn, Fe, Cu, Cr, Se,Zn) • Analysis of soils • Clinicalanalysis (bloodsamples: wholeblood, plasma,serum; Ca, Mg, Li, Na, K, Fe)

    27. REFERENCES • http://www.scribd.com/doc/10513921/Atomic-Absorption-Determination-of-Zinc-and-Copper-in-a-Multivitamin • http://www.hemlin.pp.se/USstarten.html • http://www.learn-english-today.com/business-english/presentations-phrases.htm

    28. THANKS FOR YOUR ATTENTION..