L. Yu et al. Correspondence to: Q. Zhang

Transcription

1 Supplement of Atmos. Chem. Phys. Discuss., 5, , 5 doi:.594/acpd supplement Author(s) 5. CC Attribution. License. Supplement of Molecular transformations of phenolic SA during photochemical aging in the aqueous phase: competition among oligomerization, functionalization, and fragmentation L. Yu et al. Correspondence to: Q. Zhang ([email protected]) The copyright of individual parts of the supplement might differ from the CC-BY. licence.

2 Section S: Nano-DESI measurement and data analysis The nano-desi analyses were performed using a high-resolution LTQ-rbitrap mass spectrometer (Thermo Electron, Bremen, Germany) with a resolving power (m/ m) of, at m/z = 4. The instrument is equipped with a nano-desi source assembled from two fusedsilica capillaries (5 μm o.d./5 μm i.d.) [Roach et al., ]. The analysis was performed under the following conditions: spray voltage of -5 kv,.5- mm distance from the tip of the nanospray capillary to the 5 o C heated inlet of the LTQ-rbitrap, and.-.9 μl/min flow rate of acetonitrile : water (7: volume) solvent. Both positive and negative mode mass spectra were acquired using the Xcalibur software (Thermo Electron, Inc.). Signals with S/N > were picked out using the DeconLS software developed at the Pacific Northwest National Laboratory (PNNL) [Jaitly et al., 9]. Data was further processed with Microsoft Excel using a set of built-in macros developed by Roach et al. []. The background and sample peaks were first aligned, and the peaks corresponding to C isotopes were removed. Peaks in the sample spectra that are at least times bigger than the corresponding peaks in the background spectra were retained for further analysis. Peaks were segregated into different groups using the higher-order mass defect transformation developed by Roach et al. []. Molecular formula was assigned with Formula Calculator v.. ( using the following constraints: C, H, for the negative ion mode data and C, H,, Na for the positive ion mode data. Approximately 7% of the peaks can be assigned with molecular formula within these constraints. Section S: HR-AMS measurement and data analysis In this study, a High Resolution Time-of-Flight Aerosol Mass Spectrometer (Aerodyne Res. Inc., Billerica, MA; thereinafter referred to as AMS) was used to characterize the bulk chemical composition and elemental ratios of the low-volatility substances. The working principles of the AMS have been discussed previously [DeCarlo et al., 6; Canagaratna et al., 7]. Briefly, the AMS analyzes nonrefractory aerosols that can be evaporated at ~ 6 C via 7 ev EI mass spectrometry. In this study, the AMS was operated in V mode (mass resolutions of ~ ) to acquire mass spectra up to m/z 5. The AMS data were analyzed using the AMS data analysis software (SQUIRREL v. and PIKA v.5 downloaded from The V-mode data was analyzed to obtain high resolution mass spectra (HRMS), the atomic ratios of oxygen-to-carbon (/C), hydrogen-tocarbon (H/C) and the organic mass-to-carbon ratio (M/C) [Aiken et al., 8]. The relative humidity measured at the AMS inlet was very low (< %), and we assume that contribution from gaseous water molecules was negligible. The H + signal of organics was thus determined as the difference between the measured H + signal and that produced by sulfates [Allan et al., 4].

3 Table S Top most abundant compounds identified in SYR aqsa formed during different stages of the -mediated reactions using (-) nano-desi MS. C * (μg Relative abundance (ranking) c Molecular No. formula a Proposed structure m - ) at 5 C, P: - hrs P: -4 hrs P: 4-6 hrs atm b C 6 H 8 6 (6.) CH.E- () 4 (66). (N/A) H C CH CH H C CH 4 C 5 H 8 7 (.5) C 5 H 6 6 (9.946) C 5 H 6 9 (4.794) H C.7E-5 56 () () 7 (8).4E-4 46 () 8.6 (9).4 (59).9E- 8 (4) 9 () () CH CH CH CH CH CH H C CH 5 C H 4 7 (8.79) 5.8E-8 9 (5) 48 (5) 9 () 6 C 5 H 6 8 (4.845) H C CH.8E-9 9 (6) () 5 (79) CH C 6 H 8 7 (.5) C 4 H 7 (9.58) C 5 H 8 (58.9) H C.7E-5 8 (7).7 (6).7 (58) CH 4.E- 7 (8) 9 (9) (7) H C CH CH CH CH H.5E- (9) 5 (4) 49 (5) C 4 H 4 8 (.688) H C CH 9.9E- () 45 (6) 4 (7)

4 C H 7 (68.58) H C CH.E-7 () 4 (7) 7 () H C CH C H 6 8 (.845) H C.4E-7 8. () 9 (8) 8 () C 6 H 8 6 (76.).E+4 7. (7) 56 () 8 () H C CH 4 C 4 H 6 9 (8.794) H C 7.6E- 6.7 () () 4 (8) C 5 H 6 5 (46.5) C 4 H 6 5 (4.5) C 5 H 6 6 (6.64) C 6 H 6 6 (74.64).7E+ 4.6 (48) () 4 (6).E+ 4.4 (5) 4 () 6 () 5.E- 4. (54) (4) 5 (4) 5.E-5.4 (66) 4 (6) 4 (9) a Molecular formulas and proposed structures of the top most abundant compounds identified according to (-) nano-desi spectra data. The exact molecular weight of each compound is shown in parentheses. b Estimated saturation concentrations (C *, μg m - ) of the compounds at 5 C, atm, determined using the Nannoolal vapor pressure and extrapolation method. c Relative abundances (%) of the compounds and, in parentheses, the abundance rank numbers of the compounds according to the nano-desi mass spectra of in each time period. The rank number is counted in the sorted relative abundance list of all the compounds identified in each time period. 4

5 Table S Top most abundant compounds identified in GUA aqsa formed during different stages of the C*-mediated reactions using (-) nano-desi MS. C * (μg m - ) Relative abundance (ranking) c Molecular No. formula a Proposed structure at 5 C, P: 4-6 atm b P: - hrs P: -4 hrs hrs C 4 H 4 4 (46.89) C 4 H 4 6 (78.79) C H 6 (68.59) CH CH CH CH CH CH CH 8.8E- () 6 () ().5E-5 79 () () () 4.E- 65 () 4 () 6 (6) 4 C H 8 6 (54.) CH CH 8.E-9 8 (4) (4) () 5 C H 4 (.75) CH CH 8.7E- 9 (5) 5 (9) () 6 C H 8 8 (98.) CH 5.7E-4 6 (6) (5) () 7 C H 8 (4.58) CH CH CH 5.E- 4 (7) 9 (6) 8 (4) 8 C 4 H 6 (76.64) CH.E-6 (8) 7 (7) 7 (5) CH CH 9 C 8 H 6 8 (49.67) CH CH.8E-5 (9) 4. (). (4) CH C 4 H 4 5 (6.84) CH 6.E- 9. () 7. () 4.7 () 5

6 CH C H 6 7 (68.896).6E- 9. () 6 (8) 4 (8) C H 5 (46.58) 4.7E () () 5 (7) C H 6 (64.64) CH.E-6 6. (4) () 4 (9) a Molecular formulas and proposed structures of the top most abundant compounds identified according to (-) nano-desi spectra data. The exact molecular weight of each compound is shown in parentheses. b Estimated saturation concentrations (C *, μg m - ) of the compounds at 5 C, atm, determined using the Nannoolal vapor pressure and extrapolation method. c Relative abundances (%) of the compounds and, in parentheses, the abundance rank numbers of the compounds according to the nano-desi mass spectra of in each time period. The rank number is counted in the sorted relative abundance list of all the compounds identified in each time period. 6

7 Table S Top most abundant compounds identified in GUA aqsa formed during different stages of the -mediated reactions using (-) nano-desi MS. C * (μg m - ) Relative abundance (ranking) c Molecular Proposed No. at 5 C, formula a structure atm b C 4 H 4 6 (78.79) C 4 H 4 4 (46.89) C H 6 (68.59) CH CH CH CH CH CH CH P: - hrs P: -4 hrs P: 4-6 hrs.5e-5 () () () 8.8E- 5 () 7 () 8 () 4.E- 8 () (7) 5. () 4 C H 4 (.75) CH 8.7E- (4) 5 (5) (8) 5 C H 8 6 (54.) CH CH 8.E-9 9 (5) 8. () 4.9 () 6 C 8 H 6 (5.7) 5.E+ 5 (6). (N/A).7 (8) 7 C 4 H 6 (76.64) CH.E-6 (7) 7 () 7 (4) 8 C H 5 (46.58) CH 4.7E-5 (8) 5 (4) 8 () 9 C H 8 8 (98.) CH 5.7E (9) 8.7 () 8. () C H 6 (64.64) CH.E () (6) 6 (5) 7

8 C H 4 (.579).E- 6. (6) 9.4 (9) 4 (6) 4 C H (4.6) C 7 H 6 (9.477) C 4 H 6 5 (4.5).E+ 5.5 (9) 6.7 (4) 8.7 () 4.4E-.7 () (8) (7) 5.6E+. (N/A). (N/A) 9.6 (9) a Molecular formulas and proposed structures of the top most abundant compounds identified according to (-) nano-desi spectra data. The exact molecular weight of each compound is shown in parentheses. b Estimated saturation concentrations (C *, μg m - ) of the compounds at 5 C, atm, determined using the Nannoolal vapor pressure and extrapolation method. c Relative abundances (%) of the compounds and, in parentheses, the abundance rank numbers of the compounds according to the nano-desi mass spectra of in each time period. The rank number is counted in the sorted relative abundance list of all the compounds identified in each time period. 8

9 Table S4 Top most abundant compounds identified in Ph aqsa formed during different stages of the C*-mediated reactions using (-) nano-desi MS. C * (μg m - Relative abundance (ranking) c Molecular No. formula a Proposed structure ) at 5 C, atm b P: -5 hrs P: 5-9 hrs P:9- hrs C H (.6) 9.E- () () 5.7 (8) C 8 H 4 (78.94) 6.5E-4 88 () 4 (7).5 (94) C 8 H 4 4 (94.89).4E-6 45 () 4 (8).9 (69) 4 C H (86.68) 9.E+ 7 (4) 5 ().6 (75) 5 C H (4.6).E+ (5) 4 (5) (5) 6 C 8 H 5 (8.684) 4.E-7 (6) 44 (4).8 (8) 7 C H 4 6 (5.79).E- (7) 7 () 6 (4) 8 C 4 H 8 4 (7.4) 9.E- 6 (8) 5.9 (45). (N/A) 9 C H 4 (.579).E- 6 (9) 4 (6) 4 () C 8 H 4 (9.75) 6.E-4 () 8.9 (). (77) C 4 H 5 (58.58).E-4 () (9) 7 (9) 9

10 C 8 H 6 5 (8.5) 8.8E- 5. (8) 9.4 () 8.8 () C 7 H 6 (8.7) 9.E+ 4. () 7 () (6) C 7 H 6 4 (54.66) C 4 H 4 4 (6.) C 4 H 6 5 (4.5) C 4 H 6 4 (8.66).6E+.4 (7) 9.6 () 9 (7).E+.6 (95) 6.5 (7) 8 (8) 5.6E+. (N/A) 5 () ().E+. (N/A). (N/A) 4 () a Molecular formulas and proposed structures of the top most abundant compounds identified according to (-) nano-desi spectra data. The exact molecular weight of each compound is shown in parentheses. b Estimated saturation concentrations (C *, μg m - ) of the compounds at 5 C, atm, determined using the Nannoolal vapor pressure and extrapolation method. c Relative abundances (%) of the compounds and, in parentheses, the abundance rank numbers of the compounds according to the nano-desi mass spectra of in each time period. The rank number is counted in the sorted relative abundance list of all the compounds identified in each time period.

11 Table S5 Top most abundant compounds identified in Ph aqsa formed at different stages of the -mediated reactions using (-) nano-desi MS. C * (μg m - ) Relative abundance (ranking) c Molecular Proposed No. at 5 C, formula a structure atm b P: -6 hrs P: 6- hrs P: - 4 hrs C H 4 (.579).E- () () 48 () C H (4.6).E+ 9 () 6 (4) 9 (9) C H (.6) 9.E- 48 () 4 (8). (86) 4 C H 4 6 (5.79).E- 47 (4) 68 () 9 (4) 5 C 4 H 5 (58.58).E-4 9 (5) 4 (5) 5 () 6 C 8 H 6 (5.7) 8.5E-8 7 (6) 7. (). (88) 7 C 6 H 6 5 (58.5).E- 9 (7) 7 (7) 9 (8) 8 C 7 H 6 4 (54.66).6E+ 5 (8) 7 (6) 6 (5) 9 C 8 H 6 5 (8.5) C H 4 (8.579) C 4 H 6 5 (4.5) 8.8E- 5 (9) () 7.4 () 4.7E- 4 () 9 () 4.5 (4) 5.E+. (N/A) 6 () () C H 8 (7.76) 4.7E-. (N/A) (9) (4)

12 4 5 6 C 4 H 6 4 (8.66) C 6 H 8 6 (76.) C 4 H 4 4 (6.) C 5 H 6 6 (6.64).E+. (N/A). (N/A) ().E+4 9. (9) 6 () (6).E+.6 (48) (6) (7) 5.E-.8 (44) 7. (5) 6 () a Molecular formulas and proposed structures of the top most abundant compounds identified according to (-) nano-desi spectra data. The exact molecular weight of each compound is shown in parentheses. b Estimated saturation concentrations (C *, μg m - ) of the compounds at 5 C, atm, determined using the Nannoolal vapor pressure and extrapolation method. c Relative abundances (%) of the compounds and, in parentheses, the abundance rank numbers of the compounds according to the nano-desi mass spectra of in each time period. The rank number is counted in the sorted relative abundance list of all the compounds identified in each time period.

13 (-) nano-desi MS pen-ring species (n C <6) Monomer deriv. Dimer & deriv. Trimer & deriv. Tetramer & deriv. Pentamer & deriv. % of total signal % of total signal (a) SYR + C* P P P (c) GUA + C* P P P % of total signal % of total signal (b) SYR + P P P P P (d) GUA + P % of total signal (e) Ph + C* P P P % of total signal (f) Ph + P P P Figure S. The signal-weighted distributions of (a-b) SYR, (c-d) GUA, and (e-f) Ph aqsa formed during three different stages of the C*- and -mediated reactions, respectively, based on the degree of oligomerization. The data are from the ( ) nano-desi MS spectra.

14 - - (-) DESI SYR + P: - hrs A LV-A SV-A BBA 4 5 Rel. abund. (%) S C - - P: -4 hrs A LV-A SV-A BBA - P: 4-6 hrs A Figure S. S C and n C of SYR aqsa formed during different stages of -mediated reactions determined based on (-) nano-desi MS spectra. Signals are colored by the relative abundance of the molecules. The black star at n C = 8 represents SYR. The shaded ovals indicate locations of different ambient organic aerosol classes reported in Kroll et al. (). n c BBA LV-A SV-A 4

15 - - (-) DESI GUA + C* P: - hrs A 4 5 Rel. abund. (%) LV-A SV-A BBA S C - - P: -4 hrs A SV-A BBA LV-A P: 4-6 hrs LV-A - SV-A BBA - A Figure S. S C and n C of GUA aqsa formed during different stages of C*-mediated reactions determined based on (-) nano-desi MS spectra. Signals are colored by the relative abundance of the molecules. The black star at n C = 7 represents GUA. The shaded ovals indicate locations of different ambient organic aerosol classes reported in Kroll et al. (). n c 5

16 - - (-) DESI GUA + P: - hrs A LV-A SV-A BBA 4 5 Rel. abund. (%) S C - - P: -4 hrs A LV-A SV-A BBA P: 4-6 hrs - LV-A SV-A BBA - A Figure S4. S C and n C of GUA aqsa formed during different stages of -mediated reactions determined based on (-) nano-desi MS spectra. Signals are colored by the relative abundance of the molecules. The black star at n C = 7 represents GUA. The shaded ovals indicate locations of different ambient organic aerosol classes reported in Kroll et al. (). n c 6

17 - - (-) DESI Ph + C* P: -5 hrs A 4 5 Rel. abund. (%) LV-A SV-A BBA S C - - P: 5-9 hrs A BBA SV-A LV-A P: 9- hrs LV-A - SV-A BBA - A Figure S5. S C and n C of Ph aqsa formed during different stages of C*-mediated reactions determined based on (-) nano-desi MS spectra. Signals are colored by the relative abundance of the molecules. The black star at n C = 6 represents Ph. The shaded ovals indicate locations of different ambient organic aerosol classes reported in Kroll et al. (). n c 7

18 - - (-) DESI Ph + P: -6 hrs A LV-A SV-A BBA 4 5 Rel. abund. (%) S C - - P: 6- hrs A LV-A SV-A BBA P: -4 hrs - LV-A SV-A BBA - A Figure S6. S C and n C of Ph aqsa formed during different stages of -mediated reactions determined based on (-) nano-desi MS spectra. Signals are colored by the relative abundance of the molecules. The black star at n C = 6 represents Ph. The shaded ovals indicate locations of different ambient organic aerosol classes reported in Kroll et al. (). n c 8

19 References Aiken, A. C., et al. (8), /C and M/C ratios of primary, secondary, and ambient organic aerosols with high-resolution time-of-flight aerosol mass spectrometry, Environ. Sci. Technol., 4(), , doi:./es79q. Allan, J. D., et al. (4), A generalised method for the extraction of chemically resolved mass spectra from Aerodyne aerosol mass spectrometer data, J. Aerosol Sci., 5(7), 99-9, doi:.6/j.jaerosci Canagaratna, M. R., et al. (7), Chemical and microphysical characterization of ambient aerosols with the aerodyne aerosol mass spectrometer, Mass Spectrom. Rev., 6(), 85-, doi:./mas.5. DeCarlo, P. F., et al. (6), Field-deployable, high-resolution, time-of-flight aerosol mass spectrometer, Anal. Chem., 78(4), , doi:./ac649n. Jaitly, N., A. Mayampurath, K. Littlefield, J. N. Adkins, G. A. Anderson, and R. D. Smith (9), DeconLS: An open-source software package for automated processing and visualization of high resolution mass spectrometry data, BMC Bioinformatics,, 87, doi:.86/ Roach, P. J., J. Laskin, and A. Laskin (), Nanospray desorption electrospray ionization: an ambient method for liquid-extraction surface sampling in mass spectrometry, Analyst, 5(9), -6, doi:.9/canc. Roach, P. J., J. Laskin, and A. Laskin (), Higher-order mass defect analysis for mass spectra of complex organic mixtures, Anal. Chem., 8(), , doi:./ac654j. 9