ISSAOS 2008
This presentation is the property of its rightful owner.
Sponsored Links
1 / 30

ISSAOS 2008 l‘Aquila, September 2008 Aerosol Mass Spectrometry: The Aerosol mass Spectrometer PowerPoint PPT Presentation


  • 74 Views
  • Uploaded on
  • Presentation posted in: General

ISSAOS 2008 l‘Aquila, September 2008 Aerosol Mass Spectrometry: The Aerosol mass Spectrometer Hugh Coe School of Earth, Atmospheric and Environmental Sciences University of Manchester. Reading:

Download Presentation

ISSAOS 2008 l‘Aquila, September 2008 Aerosol Mass Spectrometry: The Aerosol mass 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


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

ISSAOS 2008

l‘Aquila, September 2008

Aerosol Mass Spectrometry:

The Aerosol mass Spectrometer

Hugh Coe

School of Earth, Atmospheric and Environmental Sciences

University of Manchester

Reading:

  • D Murphy, The design of single particle laser mass spectrometers, in: Mass Spectrometry Reviews, 2007, 26, 150-165.

  • M. R. Canagaratna et al., Chemical and microphysical characterisation of ambient aerosols with the Aerodyne Aerosol Mass Spectrometer in: Mass Spectrometry Reviews, 2007, 26, 185-222.

  • H. Coe and J. D. Allan, “Aerosol Mass Spectrometry” in “Atmospheric techniques” ed D. E. Heard, Blackwell Scientific Publishing, 2006

  • http://cires.colorado.edu/jimenez/ams-papers.html


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Aerodyne Aerosol Mass Spectrometer (AMS)

http://cires.colorado.edu/jimenez/ams-papers.html

Particle

Particle Beam

Aerodynamic Sizing

Composition

Generation

Quadrupole

Mass Spectrometer

Chopper

Thermal Vaporization &

Electron Impact Ionization

TOF Region

Aerodynamic Lens

(2 Torr)

Turbo Pump

Turbo Pump

Turbo Pump

Particle Inlet (1 atm)

100% transmission (30-600 nm), aerodynamic sizing, linear mass signal.

Development of an Aerosol Mass Spectrometer for Size and Composition Analysis of Sub-micron Particles. Jayne et al., Aerosol Science and Technology 33:1-2(49-70), 2000.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Flash

Vaporization

of Volatiles

and Semi-Volatiles

Electron Emitting

Filament

Focused

Particle Beam

e-

Oven

500 C

R+

Electron Impact Ionization

AMS Detection Process

Separation of Vaporization/Ionization allows for Quantitative Measurements

Universal and quantitative chemical analysis: 0.1mg/m3 sensitivity.

Vaporization and analysis of most aerosol chemical constituents

- with primary exception of crustal oxides and elemental carbon.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Calibration & Experimental Set up…


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Quantification of Aerosol Mass…(Jimenez et al., 2003)

General Formula..

Nitrate Mass loading..

IE Ionisation EfficiencyNA Avogadro’s number

Q flow rateI ion rate

MW molecular weightC mass concentration


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Electron Impact a well defined ionisation


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Quantification of Aerosol Mass…

So the Mass loading of component s is..

IE Ionisation EfficiencyNA Avogadro’s number

Q flow rateI ion rate

MW molecular weightC mass concentration

RIE relative ionisation efficiency


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Quantification of Aerosol Mass…

Allan JD, Delia AE, Coe H, Bower KN, Alfarra MR, Jimenez JL, Middlebrook AM, Drewnick F, Onasch TB, Canagaratna MR, Jayne JT, Worsnop DR. 2004b. A generalised method for the extraction of chemically resolved mass spectra from Aerodyne aerosol mass spectrometer data. J Aerosol Sci 35:909–922, doi:910.1016/j.jaerosci.

2004.1002.1007.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

This is what we measure………

Alfarra MR, Coe H, Allan JD, Bower KN, Boudries H, Canagaratna MR, Jimenez JL, Jayne JT, Garforth A, Li S-M, Worsnop DR. 2004.

CHARACTERIZATION OF AMBIENT AEROSOLS WITH AN AEROSOL MASS SPECTROMETER &

Mass Spectrometry Reviews DOI 10.1002/mas 217

Characterization of urban and regional organic aerosols in the lower Fraser Valley using two Aerodyne Aerosol Mass Spectrometers. Atmos Environ 38:5745–5758.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Aerodyne Aerosol Mass Spectrometer (AMS)

http://cires.colorado.edu/jimenez/ams-papers.html

Particle

Particle Beam

Aerodynamic Sizing

Composition

Generation

Quadrupole

Mass Spectrometer

Chopper

Thermal Vaporization &

Electron Impact Ionization

TOF Region

Aerodynamic Lens

(2 Torr)

Turbo Pump

Turbo Pump

Turbo Pump

Particle Inlet (1 atm)

100% transmission (30-600 nm), aerodynamic sizing, linear mass signal.

Development of an Aerosol Mass Spectrometer for Size and Composition Analysis of Sub-micron Particles. Jayne et al., Aerosol Science and Technology 33:1-2(49-70), 2000.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Aerodynamic Particle Focusing

Predicted and Measured Particle Collection Efficiency

Particle Velocity Calibration


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Example of AMS Output

Organics

Sulphate

Nitrate

Ammonium


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Example of AMS Output

Organics

Sulphate

Nitrate

Ammonium


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Example of AMS Output

Organics

Sulphate

Nitrate

Ammonium


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Collection Efficiency (CE)

Matthew, B.M., T.B. Onasch, and A.M. Middlebrook. Collection Efficiencies in an Aerodyne Aerosol Mass Spectrometer as a Function of Particle Phase for Laboratory Generated Aerosols. Aerosol Science and Technology, In press, July 2008.

Takegawa, N., Y. Miyazaki, Y. Kondo, Y. Komazaki, T. Miyakawa, J.L. Jimenez, J.T. Jayne, D.R. Worsnop, J. Allan, and R. J. Weber (2005), Characterization of an Aerodyne Aerosol Mass Spectrometer (AMS): Intercomparison with other Aerosol Instruments, Aerosol Science and Technology, 39, 760-770, 2005


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Quantification of Aerosol Mass…

Including the CE, the Mass loading of component s is..

IE Ionisation EfficiencyNA Avogadro’s number

Q flow rateI ion rate

MW molecular weightC mass concentration

RIE relative IECE collection efficiency


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Understanding Organic Aerosols – Zhang et al., 2005


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Understanding Organic Aerosols – Zhang et al., 2005


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Understanding Organic Aerosols – Zhang et al., 2005

A factor analysis of the time series of organic mass spectra……


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Extended to Positive Matrix Factorisation (PMF)


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Evidence for OOA being a Secondary Photochemical Product

Data from Gaffney, Marley, Brune, Volkamer, Cardenas et al.

Mexico City

April 9, 2003

Volkamer, Jimenez, et al., GRL, 2006.


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Increase in SOA with residence time in atmosphere – observations much greater than models

DeGouw et al.

Johnson

et al.

Heald et al.

Volkamer, Jimenez, et al., GRL, 2006.

  • Much higher SOA than predicted with current models

    • Discrepancy appears to increase with time


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

A Compact Time of Flight AMS

Data from Shane Murphy Caltech


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

A High resolution time of Flight AMS


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

The Ability to resolve atomic composition


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

The Ability to resolve atomic composition


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Ambient aerosol is much more oxygenated than chamber aerosol


Issaos 2008 l aquila september 2008 aerosol mass spectrometry the aerosol mass spectrometer

Something for the future……

SP2-AMS schematic


Oil lamp soot particles

Oil Lamp Soot Particles

Obtain chemical information on elemental carbon clusters and organic compounds coating the soot cores


  • Login