acsm update - cirescires.colorado.edu/.../croteau_acsmdevelopments.pdf · 2018-05-07 · acsm...
TRANSCRIPT
Q-ACSM
ToF-ACSM
Q-ACSM and ToF-ACSM Systems
15-30 min data typical 10 min data typical
9/23/2015 AMS Users Meeting 2015 2
ToF-ACSM Sensitivity is ~5x Q-ACSM in same time
Particle Inlet (1 atm)
Thermal
Vaporization
&
Electron
Impact
Ionization
Aerodynamic Lens
40-1000 nm
Particle Beam
Generation
Particle
Composition
Quadrupole Aerosol Chemical Speciation Monitor
Laptop
Computer
RG
A
Pumps (x3)
No Sizing
Commercial grade
Mass SpectrometerPfeiffer Prisma
Slow scan rates, 0.2 sec/amu
9/23/2015 AMS Users Meeting 2015 3
ETOF
Mass Spec
Particle Inlet (1 atm)
Thermal
Vaporization
&
Electron
Impact
Ionization
Aerodynamic Lens
40-1000 nm
Particle Beam
Generation
Particle
Composition
ADQ114
4-Stage Split-Flow
No Sizing
Time-of-Flight Aerosol Chemical Speciation Monitor
9/23/2015 AMS Users Meeting 2015 4
RG
A
Sample
modeFilterFilter
mode
In ACSM, the difference airbeam signal is zero.
3-way Valve
Difference mass spectrum measured by automated valve switching
9/23/2015 AMS Users Meeting 2015 5
Requirements for PM2.5 ACSM
9/23/2015 AMS Users Meeting 2015 7
Issue Solution
Deliver particles to the lens Redesigned inlet system
Deliver particles to the vaporizer PM2.5 Lens
Detect particle mass Capture Vaporizer
ACSM Inlet for PM2.5
• Switch to straight path for filter valve• Eliminate bends in 1/8” tube• Minimize length of 1/8” Tube
Loss in 1/8” Tube
9/23/2015 AMS Users Meeting 2015 8
Coming soon…
• Q-ACSM to TOF-ACSM Upgrade• Q-ACSM Vacuum System with CTOF Mass spectrometer
• Currently putting together test/development system at ARI• Electronics and Software work in process
9/23/2015 AMS Users Meeting 2015 14