:
1
5
10
(a)
NO : HO2
3
10
1
10
-1
[H2O] = 1%
[O3]= 5 ppm
10
-3
-15
10
4
10
(b)
3
10
OH : NO3
-2 -1
I254 =10
ph cm s
0.032
0.64
6.4
x
2
10
1
10
0
10
-1
10
0
2
4
6
N2O (%)
Figure S1. Modeled steady-state (a) NO:HO2 , and (b) OH:NO3 as a function of input [N2 O] in the PAM oxidation flow reactor with mean
residence time = 80 sec for: low, medium, and high I254 = 0.032×1015 , 0.64×1015 and 6.4×1015 ph cm2 sec, respectively, at fixed [H2 O] =
1% and [O3 ] = 5 ppm.
:
NO [ppb]
2
30
25
20
15
10
5
0
(a)
5
NO : HO2
10
(b)
[H2O] = 1%
3
15
10
I254 = 6.4*10
-2 -1
ph cm s
[O3]:
1
10
0.5 ppm
5 ppm
50 ppm
-1
10
-3
10
(c)
OH : NO3
3
10
1
10
-1
10
0
2
4
N2O (%)
6
Figure S2. Modeled steady-state (a) NO, (b) NO:HO2 , and (c) OH:NO3 as a function of input [N2 O] in the PAM oxidation flow reactor with
mean residence time = 80 sec for: low, medium, and high [O3 ] = 0.5, 5, and 50 ppm respectively, at fixed [H2 O] = 1% and I254 = 6.4×1015
ph cm−2 sec.
3
NO [ppb]
:
30
25
20
15
10
5
0
(a)
5
(b)
NO : HO2
10
[O3] = 5 ppm
3
15
10
I254 = 6.4*10
[H2O]:
0.07 %
1%
2.3 %
1
10
-1
10
-3
-2 -1
ph cm s
O3 = 5 ppm
15
I254 = 6.4*10
10
(c)
OH : NO3
3
10
1
10
-1
10
0
2
4
N2O (%)
-2 -1
cm s
6
Figure S3. Modeled steady-state (a) NO, (b) NO:HO2 , and (c) OH:NO3 as a function of input [N2 O] in the PAM oxidation flow reactor with
mean residence time = 80 sec for: low, medium, and high [H2 O] = 0.07, 1, and 2.3% respectively, at fixed [O3 ] = 5 ppm and I254 = 6.4×1015
ph cm−2 sec.
4
:
NO:HO2
[NO] (ppb)
-3
OHexp (cm s)
10
2.5 x10
2.0
1.5
1.0
0.5
0
0.25
0.20
0.15
0.10
0.05
0
2.0
(a)
36 ppb isoprene
[H2O] = 1%, [O3] = 5 ppm
I254 = 6.4*10
13
-2
ph cm
-1
(b)
s
(c)
1.5
1.0
0.5
OH:NO3
0
10
(d)
1
0.1
0.01
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
[N2O] (%)
Figure S4. Modeled steady-state (a) OH exposure, (b) [NO], (c) NO:HO2 , and (d) OH:NO3 as a function of input [N2 O] corresponding to
isoprene + OH oxidation conditions at low OH exposure in the PAM reactor. Error bars represent uncertainty in model outputs (Peng et al.,
2015) and in accuracy of N2 O flow controller.
:
5
8
-3
OHexp (cm s)
[NO] (ppb)
12
2.5 x10
2.0
1.5
1.0
0.5
0
12
(a)
36 ppb isoprene
[H2O] = 1%, [O3] = 5 ppm
I254 = 3.2*10
15
-2
ph cm
(b)
-1
s
4
0
(c)
NO:HO2
10
1
0.1
OH:NO3
0.01
100
(d)
10
1
0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
[N2O] (%)
Figure S5. Modeled steady-state (a) OH exposure, (b) [NO], (c) NO:HO2 , and (d) OH:NO3 as a function of input [N2 O] corresponding to
isoprene + OH oxidation conditions at high OH exposure in the PAM reactor. Error bars represent uncertainty in model outputs (Peng et al.,
2015) and in accuracy of N2 O flow controller.
6
:
-3
s)
(a)
4
(cm
OHexp
2
11
10
2
10
10
(b)
16
s)
[NO] (ppb)
(cm
-3
O3,exp
1.0 x10
0.5
0
20
15
10
5
0
(c)
(d)
NO:HO2
3
10
0
10
-3
OH:NO3
10
10
(e)
1
0.1
0.01
0
1
2
3
4
5
6
[N2O] (%)
Figure S6. Modeled steady-state (a) OH exposure, (b) O3 exposure, (c) [NO], (d) NO:HO2 , and (e) OH:NO3 as a function of input [N2 O]
corresponding to isoprene + OH oxidation conditions at low OH exposure in the PAM reactor. Error bars represent uncertainty in model
outputs (Peng et al., 2015) and in accuracy of N2 O flow controller.