acsm advances - cires

ACSM Advances

CACC Folks

Phil Croteau

January 20, 2021 Virtual AMS Users Meeting 2021 1

Outline

• TOF-ACSM Software

• Q-ACSM Mass Spec News

• Calibration kit work

• TOF-ACSM X

• “Answers” to submitted questions


excluded from average

Acquility v2.3.9+

Moved from “Fast Switching” to “Time Resolved Evaporation”

Cube averaging for TRE mode enables manageable file size.


Tofware 3

Leah will hold tutorial on Friday AM

Workflow 1

Workflow 2Divide analysis tasks into two “workflows”

1. Generate ‘diff stick’ mass spectra

2. Do AMS/ACSM analysis (species, etc.)January 20, 2021 Virtual AMS Users Meeting 2021 4

Q-ACSM – Pfeiffer will stop producing PrismaPlus and move to new PrismaPro

• Prototype PrimsaPro ACSM built up

• New electronics design in testing

• DAQ software in process

• Initial data look similar to PrismaPlus

• More analog and digital I/O


Calibration kit development

Atomizer

Water trap

Dryer

DMA

CPC

ACSM

exhaust

Sample Pump

exhaust

ambient

ACSM filter-switching

• Switch between calibration and ambient (ACSM + SMPS) mode

• Ben Nault working on evaluation and prototype


Compact kit via Aerosol Dynamics3D printed design via Dan Cziczo

Particle Counting – Aerosol Dynamics MAGIC CPC


Moderated Aerosol Growth with Internal water Cycling

• Compact

• Water-based

• Ambient humidity is often enough water (no reservoir needed)

MAGIC compares well with a calibrated TSI 3776


Ben Nault’s data

Particle size selection – Spider DMAStavros Amanatidis (CalTech) and Susanne Hering (ADI)


Spider DMA Transfer Function


Resolution ~3Dp max ~500nm


300 nm NH4NO3

measured with AMS

from Spider and TSI DMAs

MAGIC Spider Measured Cooking Aerosol



Q-ACSM Calibration comparing

TSI and Spider DMA

TOF-ACSM X

• Same footprint as TOF-ACSM• FTOF mass spectrometer

• Simplified/more robust HTOF• Resolution ~2000 m/dm• Same data system as TOF-ACSM• Can provide

• Explicit H:C, O:C• Improved NH4 with HR fitting

• ARI got this as Christmas present• Characterizing in lab now



TOF-ACSM XResolution

(first measurements) No Vaporizer~2100 m/dm

With Vaporizer~1820 m/dm

Very quick tune done after vaporizer install – definitely room for

improvement

High resolution enables improved NH4

quantification



High resolution enables improved NH4

quantification

Don’t believe absolute scale (analysis needs work) – just compare S/N

Sample HR Fits at m/z 43, 57


Average Org Mass Spec


Average*H:C = 1.52O:C = 0.45

*Not sure I’ve got calculation quite right yet

Q&A• To miniAMS-users: Which pressure do you have in the aerodynamic lens?

• For mAMS and TOF-ACSM, PM1 lens pressure should be ~1.75 mbar

• What is a suitable AB for ToF-ACSM ambient measurements and the typical response factor for that?• 1-4e5 ions/s, with an IE 100-500 ions/pg

• I would like to know the influence of m/z 44 artefacts in individual instruments, how it impact the results and the PMF analysis. • For our best on how to deal with m/z 44 artefacts see Freney et al., Aerosol Science and

Technology, 53:7, 830-842, DOI: 10.1080/02786826.2019.1608901

• ACSM Igor Updated Manual available?• No – we’re doing more Knowledge Articles to deal with specific questions, though

• Will acsm software be moved to Igor 7 or 8 (if not already)?• Tofware 3 is Igor 7/8 compatible• Acquility 2.3 is Igor 7 compatible• Q-ACSM works on Igor 6-8


• Can the ACSM x resolve both CH2O+ and NO+ at m/z 30?


Q&A

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