Experiment: 2014 FIXCIT Study_20140124_4-hydroxy-3-nitrooxy ISOPN/Methyl nitrite/nitric oxide/_Hydroxyl radical_Ammonium sulfate_4,3-isoprene hydroxynitrate + OH, high NO, 50% RH, (NH4)2SO4 seed


Name: 2014 FIXCIT Study_20140124_4-hydroxy-3-nitrooxy ISOPN/Methyl nitrite/nitric oxide/_Hydroxyl radical_Ammonium sulfate_4,3-isoprene hydroxynitrate + OH, high NO, 50% RH, (NH4)2SO4 seed
Date: 2014-01-24

2014 FIXCIT Study

Seinfeld chambers

Experiment Set
FIXCIT experiments

To observe the products of 4-OH-3-ONO2-ISOPN + OH oxidation in the presence of wet ammonium sulfate seeds. In particular, we would like to achieve a constraint on the yield of the dihydroxydinitrate (DHDN) product. In addition to DHDN, expected products include C4-hydroxy-carbonyl nitrate (MVKN, mm=149), formaldehyde, hydroxyacetone, and glycolaldehyde. We also explored GTHOS OH interference at the end of the experiment. We conclusively saw increasing interference once NO was titrated out of the bag, and significant amounts of ozone were present. It scaled with ozone addition.

John Crounse successfully separated most of the hexanes/ethyl acetate from a synthesized sample of 4,3 ISOPN. RH was added to the bag to 55%. GHTOS managed to grab a humid background, which is key. Isoprene hydroxy nitrate was successfully added to the bag. No impurities were noticed on the GC from the 4,3 ISOPN std. Lights were turned on (we should do it off-hour so that NO-CL can measure right when lights turn on/off). Mostly the methylvinylketone nitrate (MVKN, MW = 149) was made. AMS noticed about 4ug/m3 of organic mass, and TD-LIF reported ~70ppt of aerosol particles. After about 2 hours, oxidation significantly slowed down. When 100% lights on, oxidation sped up a bit, but leveled off, as did NO concentration, indicating a lack of OH. Potentially significant photolysis of m234 was noticed. When lights were turned off, everything stabilized. There was enough NO to completely titrate the roughly 20ppb O3 that had formed during the experiment. After lights off, multiple levels of O3 were added to the bag to explore wthe OH interference question.

Additional Notes
Instrument Status: TD LIF - up PTRMS - up CRM OHR - up GTHOS - up LIF OHR - up NO CL - up GLY LIP - down FOR LIF - up I/A CIMS - down half way through due to pump accidentally getting unplugged NCIMS - up RHTO3 - up GC FID - up AMS - up TQC1 - up TQC2 - up TOFCIMS - up Bag Additions: ~55% RH @ 25C ~10ppb 4,3 ISOPN nitrate 40ppb CH3ONO (1.600 torr in 500mL bulb) 110 ppb NO 110ug/m3 (NH4)2SO4 seed aerosol Timeline (UTC, hrs): 16:15: started humidifying bag 16:50: power tripped on humidifier, GTHOS 16:55: started humidifying bag again 17:40: RH @ ~50% 17:55: 4,3 ISOPN injection started 18:30: ISOPN injection stopped 18:32: bag mixing 18:34: all instruments sampling 19:15: seed addition to bag (0.06M ammonium sulfate) 19:21: seed addition stopped 19:40: seed addition to bag (0.10M ammonium sulfate) 19:50: bag mixing 19:52: bag mixing 19:55: seed addition stopped 19:58: bag mixing 20:04: CH3ONO injection into bag 20:14: bag mixing 20:25: NO injection for 60s 20:38: bag mixing 20:46: NO concentrations at ~110ppb 21:00: Lights on @ 10% 22:46: 100% lights on 24:10: I- CIMS reports being unplugged accidentally 24:20: Lights OFF 24:48: Injected air to prepare for O3 injection (~30sec) 24:52: Injecting O3 for 2 min, 28sec, roughly 20ppb drop in NO 25:05: Injecting O3 for 2 min, 28 sec, roughly titrated out 95% of NO 25:22: Injecting O3 for 8min, roughly 100ppb 25:51: Started injecting O3 to ~250ppb 26:00: Chamber work lights turned off 26:03: Chamber work lights turned back on 26:08: Stopped injecting O3, reached 250ppb 28:34: Experiment over, bag started flushing

Experiment Details


  • Gas phase chemical reaction
  • Aerosol formation
Temperature: 26
Relative Humidity: 52
Seeded Experiment: Yes
Type of Seed: Ammonium sulfate
Initial Seed Concentration Value: 110
Seed Concentration Units: micrograms_per_cubic_meter
Fuchs Adjusted Surface Area:
Condensation sink rate coefficient: 52
Reaction type:
Oxidant Name: Hydroxyl radical
Initial Oxidant Concentration Value: 3e6 (molecules_per_cubic_centimeter)
RO2 Main Fate: NO
RO2 Lifetime: (Seconds)
Pressure: 750 Torr

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

Experiment Set Details

Name: FIXCIT experiments
Time format and units: Seconds past midnight
The Focused Isoprene eXperiment at the California Institute of Technology (FIXCIT) was a collaborative study at the atmospheric chambers of Caltech during January 2014. FIXCIT is the laboratory component of SOAS, and is aimed toward (1) better understanding the chemical details behind ambient observations relevant to the southeastern United States, (2) advancing the knowledge of atmospheric oxidation mechanisms of important biogenic hydrocarbons, and (3) characterizing the behavior of field instrumentation using authentic standards. A series of chamber experiments was conducted to investigate the oxidation of isoprene, α-pinene, methacrolein, pinonaldehyde, acylperoxy nitrates, isoprene hydroxy nitrates (ISOPN), isoprene hydroxy hydroperoxides (ISOPOOH), and isoprene epoxydiols (IEPOX). Pinonaldehyde and isomer-specific standards of ISOPN, ISOPOOH, and IEPOX were synthesized, enabling study of the oxidation mechanisms and instrument responses for these compounds.


  • Allen H. Goldstein UC Berkeley
  • William H. Brune Penn State University
  • Ronald C. Cohen UC Berkeley
  • Delphine K. Farmer Colorado State University
  • Manjula R. Canagaratna Aerodyne
  • Douglas R. Worsnop Aerodyne
  • Jose L. Jimenez University of Colorado Boulder
  • Frank N. Keutsch Harvard
  • Saewung Kim UC Irvine
  • Alex B. Guenther UC Irvine
  • John E. Mak SUNY Stonybrook
  • Geoffrey S. Tyndall NCAR
  • Denise D. Montzka NCAR
  • Andrew J. Weinheimer NCAR
  • Alam Hasson Fresno State


Principal investigators:

Paul O. Wennberg
Phone: 626 395 2447
E-mail: wennberg@caltech.edu
OrcID: 0000-0002-6126-3854

John H. Seinfeld
Phone: 626-395-4635
E-mail: seinfeld@caltech.edu
OrcID: 0000-0003-1344-4068

John D. Crounse
Phone: 626-395-8655
E-mail: crounjd@caltech.edu
OrcID: 0000-0001-5443-729X

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

Data Manager:

Tran B. Nguyen
Phone: 5307525987
E-mail: tbn@ucdavis.edu


Reactant Compound type Concentration Concentration units
4-hydroxy-3-nitrooxy ISOPN
  • Alcohol
  • Alkene
  • Nitrate
12 Parts Per Billion
Methyl nitrite
  • NOx
40 Parts Per Billion
nitric oxide
  • NOx
110 Parts Per Billion
Aerosol 110 Microgram Per Cubic Meter

20140124_expTimeline.csv Timeline

UTC_hr Action
16:15 started humidifying bag
16:50 power tripped on humidifier/GTHOS
16:55 started humidifying bag again
17:40 RH @ ~50%
17:55 4-3-ISOPN injection started
18:30 ISOPN injection stopped
18:32 bag mixing
18:34 all instruments sampling
19:15 seed addition to bag (0.06M ammonium sulfate)
19:21 seed addition stopped
19:40 seed addition to bag (0.10M ammonium sulfate)
19:50 bag mixing
19:52 bag mixing
19:55 seed addition stopped
19:58 bag mixing
20:04 CH3ONO injection into bag
20:14 bag mixing
20:25 NO injection for 60s
20:38 bag mixing
20:46 NO concentrations at ~110ppb
21:00 Lights on @ 10%
22:46 100% lights on
24:10 I- CIMS reports being unplugged accidentally
24:20 Lights OFF
24:48 Injected air to prepare for O3 injection (~30sec)
24:52 Injecting O3 for 2 min 28sec; roughly 20ppb drop in NO
25:05 Injecting O3 for 2 min 28 sec; roughly titrated out 95% of NO
25:22 Injecting O3 for 8min; roughly 100ppb
25:51 Started injecting O3 to ~250ppb
26:00 Chamber work lights turned off
26:03 Chamber work lights turned back on
26:08 Stopped injecting O3; reached 250ppb
28:34 Experiment over; bag started flushing

Light Flux Characterizations:
2013-12-16 (#19)
Particle Loss Characterizations:
Vapor Loss Characterizations:

Chamber Details

Name: Seinfeld chambers
Volume in cubic meters: 22
Shape: Rectangular Prism
Surface area in cubic meters: 48
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: 40 ppt
Particle background in micrograms per cubic meter: < 0.01 ug/m3
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): 10
Temparature range (max degrees celcius): 45
Humidity Control: Yes
Humidity Measurements Recorded: Yes
Relative humidity range (min percent): 4
Relative humidity range (max percent): 90
Particle experiment capability: 1
Lights: Yes
Light source type(s): UV black lamps (350 nm centered)
Supplemental information: https://www.worldscientific.com/doi/abs/10.1142/9789813147355_0001
Additional Notes: