Experiment: Nguyen Group_20210419_2-methylbut-3-ene-1,2-diol/OZONE_Ozone_Ammonium sulfate


Name: Nguyen Group_20210419_2-methylbut-3-ene-1,2-diol/OZONE_Ozone_Ammonium sulfate
Date: 2021-04-19

Nguyen Group

Tran's big bag of air

Experiment Set
1,2-dihydroxy isoprene (DHI)

Oxidation product & SOA formation study on 2-methylbut-3-ene-1,2-diol (1,2-DHI) ozonolysis under humid (50% RH) conditions.

1,2-DHI and ammonium sulfate seed aerosol were injected into a humidified chamber and the bag was mixed and allowed to equilibrate. Ozone was injected over the course of 2 minutes with pulses of mixing air. Ozonolysis and SOA formation were allowed to continue for ~5.5 hours before shutdown. At ~4:15pm an MSMS scan of m/z 169 was performed to help identify this product.

Experiment Details


  • Gas phase chemical reaction
  • Aerosol formation
Temperature: 22
Relative Humidity: 56
Seeded Experiment: Yes
Type of Seed: Ammonium sulfate
Initial Seed Concentration Value: 350
Seed Concentration Units: micrograms_per_cubic_meter
Fuchs Adjusted Surface Area:
Condensation sink rate coefficient: 56
Reaction type:
Oxidant Name: Ozone
Initial Oxidant Concentration Value: 650 (parts_per_billion)
RO2 Main Fate: Not Sure
RO2 Lifetime: (Seconds)
Pressure: 755

Data Set plots
Choose a file: Choose the X-Axis:

Experiment Set Details

Name: 1,2-dihydroxy isoprene (DHI)
Time format and units: HH:MM, local time
A series of experiments to investigate the gas-phase oxidation rate of 1,2-dihydroxy isoprene, its oxidation products via various RO2 pathways, and the effects of including seed (AS = ammonium sulfate) particles both on observed gas-phase products and on SOA formation.


  • Kelvin H Bates Harvard / UC Davis


Principal investigator:

Tran B. Nguyen
Phone: 5307525987
E-mail: tbn@ucdavis.edu
OrcID: 0000-0001-9206-4359

Data Manager:

Kelvin H. Bates
E-mail: kelvinhbates@gmail.com


Reactant Compound type Concentration Concentration units
2-methylbut-3-ene-1,2-diol (185554)
  • Alcohol
  • Alkene
  • Diol
100 Parts Per Billion
OZONE (24823) 650 Parts Per Billion

timeline_210419.csv Timeline

Time_local_HHMM Action
8:55 Start humidifying
9:10 SMPS & CIMS on
9:40 Stop humidifying
9:45 Start DHI injection
9:53 Start atomizing AS
10:23 All injections stop; pulse mixing air
11:32 Inject O3 for 120 seconds with mixing air pulsing
16:15 Switch CIMS to MSMS mode to identify m/z 169 product
17:05 Shutdown

Light Flux Characterizations:
Particle Loss Characterizations:
Vapor Loss Characterizations:

Chamber Details

Name: Tran's big bag of air
Volume in cubic meters: 10
Shape: Rectangular Prism
Surface area in cubic meters: 28
Flow Mode: Batch
Flow through rate in liters per minute:
Body Material: Teflon
Body thickness: 2
Replacement date:
Replacement frequency: As needed
Cleaning method: Flushing with air Flushing with air with UV lights on Oxidation
o3 background: < 0.5 ppb
nox background:
Particle background in micrograms per cubic meter:
Air filtration method: Custom filtration canisters to remove NOx, hydrocarbons, water, particles, ozone, SOx from pressurized ambient air.
Mixing method: 1
Mixing method material: Pulsed air jets, manually actuated
Temparature Control: Yes
Temparature measurements recorded: Yes
Temparature range (min degrees celcius):
Temparature range (max degrees celcius):
Humidity Control: Yes
Humidity Measurements Recorded: Yes
Relative humidity range (min percent):
Relative humidity range (max percent):
Particle experiment capability: 1
Lights: Yes
Light source type(s): UV broadband black lights (centered at 350 nm)
Supplemental information:
Additional Notes: 40-Watt, Osram/Sylvania 350nm black lights, 48” long, T12 fluorescent; 72 bulbs, 36 each on two facing walls, with UV-reflective siding on all walls. Lights are controlled via 6 panels (3 on the right wall - top, mid, bottom - and 3 equivalent on the left wall).