peer review - instrumental analysis · · 2016-03-01monday (march 7)- exam 1 due: experiment 6...

2/29/16

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LOOKINGAHEADMonday(Feb29)-X-raytechniques

Due:Experiment1Report

Tuesday/Thursday(March1,3)-Experiment3-ColorsandCalories

DueTuesday:Experiment5Procedure

DueThursday:Exp1PeerReview;Exp3AnnotatedFigures

Monday(March7)-Exam1

Due:Experiment6Procedure

Tuesday/Thursday(March8,10)-Experiment4/5-SEMandCYOA

DueTuesday:Experiment3Report

DueThursday:Experiment1revisions,Experiment3peerreview

--SpringBreakMarch14-18--

Monday(March21)-Chromatography

PEERREVIEW

CHEM314

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PEERREVIEW

h:p://blogs.plos.org/biologue/files/2012/08/Peer-Review-Nick-Kim-cartoon3-resize.jpg

TYPICALJOURNAL-STYLEREVIEW

1. Decision

Accept,minorrevisions,majorrevisions,reject2. Summary

Researchstudy,overallpresenta]on,]melinessofresearchtopic

3. Majorpoints

Logicalprogression,conclusionsfollowdata,organiza]on

4. MinorpointsGrammar,spelling,wordchoice,etc

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LEARNINGCHECK

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Dunlap,1997

1. Vacuum2. Electrongenera]on3. Electronbeamcondi]oning4. Electron-sampleinterac]ons5. Detec]on

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h:p://www.telegraph.co.uk/news/science/picture-galleries/

POLLENS

30NMPOLIOVIRUS

h:p://en.wikipedia.org/wiki/Transmission_electron_microscopy

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h:p://d32ogoqmya1dw8.cloudfront.net/images/research_educa]on/geochemsheets/techniques/asbestos_3.jpgh:p://www.ecfia.eu/img/asbestos-fibres.jpg

NATURALASBESTOS

10 m

Quartz

Te-rich material

O

Fe FeFeC

Si

Cu CuMo

Te

TeTe

X-ray Energy (keV) 0 5 10

X-ra

y In

tens

ity 3000

2250

1500

750

0

TELLURIUMINMINETAILINGS

Te-bearing particles

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FLAVORSOFELECTRONMICROSCOPYScanningElectronMicroscopy(SEM)FEIQuanta200

Op]mizedforexamina]onofsampletopographyandmorphology

TEM

EMPA

SEM ElectronMicroprobeAnalysis(EMPA)JEOLJXA-8530FRequiredflatsample(thinsec]on)Quan]fica]onofelements(andminerals)

TransmissionElectronMicroscopy(TEM)JEOL1200

Shapes,density,size

Diffrac]onpa:ernsandelementalanalysis

POTENTIALELECTRON-SAMPLEINTERACTIONS1. BackscaZeredelectrons

2. Secondaryelectrons3. Fluorescentx-rays

4. Augerelectrons

5. Cathodeluminescence

6. Specimencurrent

7. TransmiZedelectrons8. ScaZering

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X-RAYTECHNIQUES:X-RAYABSORPTIONSPECTROSCOPY(XAS)X-RAYFLUORESCENCE(XRF)X-RAYDIFFRACTION(XRD)

CHEM314

OBJECTIVES

Describeanddiagramhowx-raysinteractwithsampleatomsandlabelK,L,Mshelltransi]ons.

DiagramX-rayabsorp]onandfluorescenceinstruments,describehowtheycanbeusedtomakemeasurements,andwhatinforma]onisobtainedfromeachanalysis.

DescribewhatX-raydiffrac]onisusedforandhowtheinforma]onisobtained.

BeabletouseBraggslawtorelateangleofincidence,energyofincidentradia]on,andwithplanesinacrystal

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X-RAYRADIATION

Ionizingradia]on-removeaninnerelectronfromanatom

=10-6nmto10nm

Generallyused0.012.5nm

SELECTEDHISTORY

1895-Firstx-rayimagetakenbyWilhelmRntgenofhiswifeshand.Whenshesawit,shesaidIhaveseenmydeath

1913-HenryMoseleyiden]fiedatomicnumber(notmass)asthekeytoorganizingtheperiodictable

1915-NobelPrizetotheBraggsfordeterminingthecrystalstructureofNaCl,ZnS,anddiamond.UsingBraggsLaw:n=2dsin

2006-NobelprizeinChemistrytoRogerKornbergfordeterminingthestructureofRNApolymeraseusingXRD.

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X-RAYGENERATION

1. X-raytube-Bombardingmetalwithhighenergyelectrons

2. Exposuretoprimaryx-raybeamtogeneratex-rayfluorescence

X-RAYGENERATION


2. Exposuretoprimaryx-raybeamtogeneratex-rayfluorescence3. Radioac]vedecay

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X-RAYGENERATION


2. Exposuretoprimaryx-raybeamtogeneratex-rayfluorescence3. Radioac]vedecay

4. Synchrotronradia]on

SynchrotronRadia]onPrimerHelmutWiedemann

DETECTINGX-RAYS1. GasFlowDetector

2. Energydispersivedetector3. AreaDetector

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X-RAYINTERACTIONSWITHMATTER1. Absorp]on X-rayAbsorp]onSpectroscopy(XAS)

Fluorescence X-rayfluorescence(XRF) Auger AugerElectronSpectroscopy(AES)

2. ScaZering X-raydiffrac]on(XRD)

INTERACTIONOFX-RAYSWITHMATTER1. Primaryx-rayknocksoutatomiccoreelectron.

2. Anothercoreelectronfillsthevacantcorehole.3. Addi]onalenergyreleasedfromatombyreleaseof

Augerelectronorfluorescentx-ray.

31,814eV

IncomingX-ray

KLMnucleus

Ejectedelectron

K-edge

4,341eV

L-edgee-

e-

Core-holefilled

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h:p://www.amptek.com/xrf.html

INTERACTIONOFX-RAYSWITHMATTER

h:p://www.amptek.com/xrf.html

INTERACTIONOFX-RAYSWITHMATTER

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TRANSITIONS

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Fluorescence X-rayfluorescence(XRF)

FluorescenceDetector

AsAsFe

Fe

SampleSource

Monochroma]cx-rays

TransmissionDetector



SampleSource

Monochroma]cx-rays


ElectronyieldDetector

e-e- e-

e-

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2. ScaZering X-raydiffrac]on(XRD)

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XAS

X-RAYABSORPTIONSPECTROSCOPYSource Synchrotron-monochroma]candtunableDetector GasFlowanalyzer/ionchamber

Measure Changeinabsorp]oncoefficientasafunc]onofincidentx-ray energy

Informa]on Averageatomic-scale bondingenvironment ofspecificelement

SampleSource

Monochroma]cx-rays


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Slidefrom:Bri:Hedman,SSRL

Slidefrom:Bri:Hedman,SSRL

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31.6 31.8 32.0 32.2 32.4 32.6

mu

Energy (keV)

XANES XANESElectronicInforma]onoxida]onstatefingerprintofphasemineralphases

Temetal

X-RAYABSORPTIONNEAR-EDGESPECTROSCOPY(XANES)

EDGEFEATURESCANINDICATEOXIDATIONSTATE

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31.6 31.8 32.0 32.2 32.4 32.6

mu

Energy (keV)

EXAFSXANES

2 4 6 8 10 12 14 16

k3

(k)

k (A-1)

EXAFSGeometricInforma]onBondingenvironmentCoordina]onnumberIden]ty&distancetonearestneighbors

2 4 6 8A

mpl

itude

(arb

. uni

ts)

Distance (A)

2.86

3.46

4.45

FFT

Temetal

EXTENDEDX-RAYABSORPTIONFINESTRUCTURE(EXAFS)

0 2 4 6 8Distance (A)

0 2 4 6 8Distance (A)

2Teatomsat2.86

4Teatomsat3.46

6Teatomsat4.45

Te

2.83,CN=3.2

3.47,CN=4.1

4.42,CN=4.9

S020.49E01520.0009

2.86

3.74

Wyckoff,1963

31800 32100 32400 32700

Nor

m. i

nten

sity

Energy (eV)

2 4 6 8 10 12 14 16

k3

(k)

k (A-1)

5

Temetal

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X-RAYABSORPTIONSPECTROSCOPYXASisalsoooenmeasuredinfluorescencegeometrybecausefluorescencemeasurementsareinherentlymoresensi]vethanabsorp]on.

Electronyielddetectorscanalsobeused.

SampleSource

Monochroma]cx-rays



AsAsFe

Fe

h:p://en.wikipedia.org/wiki/Auger_electron_spectroscopy

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XRF

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X-RAYFLUORESCENCE

Source monochroma]c(laborsynchrotron)

Detector energyorwavelengthdispersivedetector

Measure Measureintensityoffluorescentx-raysgeneratedatdifferent energiesatafixedincidentenergy

Informa]on Elementalcomposi]on


AsAsFe

Fe

SampleSource

Monochroma]cx-rays

Energy(keV)

Fluo

rescen

cecou

nts

As

Fe

105 15

X-RAYSFLUORESCENCEFluorescentX-rayenergyischaracteris]cofapar]culartransi]onwithinanatomofaspecificelement

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Energy(keV)Fluo

rescen

cecou

nts

As

Fe

105 15

Sample

Detector

AsAsFe

Fe

Source13keVX-rays

ENERGY DISPERSIVE XRF

h:p://www.panaly]cal.com/Axios.htmh:p://www.xos.com/techniques/xrf/wavelength-dispersive-x-ray-fluorescence-xrf/

WAVELENGTHDISPERSIVEXRF

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0

5

10

15

20

T2.6T3.9T4.2

TailingsMn

T5.4

Met

al (g

kg-

1 )

ZnT2.6T3.9T4.2T5.4 T2.6T3.9T4.2T5.4

Zn Mn

T5.4

T4.2

T3.9

T2.6

2mm2mm

2mm

2mm

2mm

2mm

2mm 2mm

Zn association with Mn

Mn

Zn

Mn

Zn

Mn

Zn

Mn

Zn

Hi Low

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XRD

WHATCANX-RAYDIFFRACTIONBEUSEDFOR?

Mineralogicalanalysis

Stressandstraininmaterials Determina]onofproteinstructure

Par]clesize

Add11-3data

h:p://en.wikipedia.org/wiki/Transmission_electron_microscopy

Addmardetectorfileshowingrings

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X-RAYDIFFRACTIONSource Monochroma]c(laborsynchrotronsource)

Detector GasFlowanalyzer

Measure Changeinx-rayscaZeringasafunc]onofanglebetweenthe source,sample,anddetector

Informa]on AngleofscaZeringisrelatedtodistancesbetweenplanesina crystal. PhaseIDandstructuraldetermina]on

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SCATTERING

BraggsLawn=2dsin

n=diffrac]onorder =wavelengthofincidentx-rayd=distancebetweencrystalplanes=incidentangleofx-raysrela]ve

toplanenormal

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CheckwebsiteforBraggslawderiva]onlink.

Ihaveagreatoneinmynotes

GOINIOMETER

Scintag,Inc.Chapter7:BasicsofX-raydiffrac]on

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LOOKINGAHEADMonday(Feb29)-X-raytechniques

Due:Experiment1Report

Tuesday/Thursday(March1,3)-Experiment3-ColorsandCalories

DueTuesday:Experiment5Procedure

DueThursday:Exp1PeerReview;Exp3AnnotatedFigures

Monday(March7)-Exam1

Due:Experiment6Procedure

Tuesday/Thursday(March8,10)-Experiment4/5-SEMandCYOA

DueTuesday:Experiment3Report

DueThursday:Experiment1revisions,Experiment3peerreview

--SpringBreakMarch14-18--

Monday(March21)-Chromatography

peer review - instrumental analysis · · 2016-03-01monday (march 7)- exam 1 due: experiment 6...

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