of 16
1
Electrode Surface Heating with Organic Films Improves CO
2
Reduction Kinetics on Copper
Nicholas B. Watkins,
†a,b
Yungchieh Lai,
†a,c
Zachary J. Schiffer,
a,c,
Virginia M. Canestraight,
a,b
Harry A. Atwater,
a,c
Theodor Agapie,
a,b,
* Jonas C. Peters,
a,b,
* John M. Gregoire
a,c,
*
a
Liquid Sunlight Alliance, California Institute of Technology, Pasadena, CA, 91125, USA.
b
Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA, 91125, USA
c
Division of Engineering and Applied Science, California Institute of Technology, Pasadena, CA, 91125, USA
*Email:
agapie@caltech.edu
,
jpeters@caltech.edu
,
gregoire@caltech.edu
These authors contributed equally to this work.
Present address: Applied Physics, Harvard John A. Paulson School of
Engineering, Harvard University, Cambridge, MA 02138
Supplemental Information
Materials and methods..........................................................................................................................................
..
2
Synthesis of diphenyliodonium triflate...............................................................................................................
...
2
High
-
throughput electrochemical testing.............................................................................................................
.
2
COMSOL modeling information...........................................................................................................................
...
3
Parameter estimation for CO
2
reduction............................................................................................................
....
3
Figure S1:
Internal temperature comparison...................................................................................................
....
4
Table S1:
Internal temperature comparison......................................................................................................
...
4
Figure S2:
Temperature
-
dependent ferri/ferrocyanide OCV calibration.........................................................
...
5
Table S2:
Electrode microenvironment temperatures using OCV..................................................................
.....
5
Figure S3:
Cyclic voltammograms of ferricyanide at variable surface temperatures....................................
....
6
Figure S4:
Chronoamperometry of ferricyanide at variable surface temperatures.......................................
....
7
Figure S5:
Concentration boundary layer thickness at variable flow rates at 25
°C
.......................................
...
8
Figure S6:
Concentration boundary layer thickness at variable surface temperatures.................................
...
8
Figure S7:
Temperature vs resistance plot of surface and bulk heated systems.............................................
...
9
Figure S8:
Variable temperature and potential CO
2
R
FE
on bare polycrystalline Cu.......................................10
Figure S9:
CO
2
R partial current density on bare polycrystalline Cu.......................................................................10
Figure S10:
Variable temperature and potential CO
2
R
FE
on additive
-
modified polycrystalline Cu .............11
Figure S
11
:
CO
2
R partial current density on
additive
-
modified polycrystalline Cu ..................
.....................
1
1
Figure S1
2
:
Reproducibility of ethylene formation at select condition.......................................
.....................12
Figure S1
3
:
Fitting of experimental data to Butler
-
Volmer kinetics (Equation 2 in main text).....................1
3
Table S3:
All raw data....................................................................................................................................
..
1
4
-
1
5
References
.............................................................................................................................................................1
6
2
Materials and Methods
All solvents and reagents were obtained from commercial sources and used as received, unless stated
otherwise. Cu foils (99.999% Cu, 25 mm × 25 mm × 0.5 mm), potassium carbonate (99.995%), potassium ferricyanide
(≥99%), potassium ferrocyanide hydrate (99.9
5%) were purchased from Sigma Aldrich. Carbon rods (99.999% C)
were purchased from Strem Chemicals. Platinum foil (99.99% Pt, 25 mm × 25 mm × 0.05 mm), was purchased from
Alfa Aesar. Natural abundance CO
2
(Research grade) was purchased from Airgas. Water w
as purified by a Nanopure
Analytical Ultrapure Water System (Thermo Scientific) or a Milli
-
Q Advantage A10 Water Purification System
(Millipore) with specific resistance of 18.2 MΩ·cm at 25 °C.
Prior to each use, copper foil was mechanically polished to a mirror
-
like finish using nanodiamond
suspension (first 3 μm then 0.1 μm, Buehler) followed by rinsing in water and drying under a stream of nitrogen gas.
The copper foil was then electropolished
using a method similar to the one employed by Kuhl
et al
.: In a 85%
phosphoric acid bath, +2.1 V versus a carbon rod counter electrode was applied to the Cu foil for 5 minutes and the
foil was subsequently washed with copious amounts of ultra
-
pure water a
nd dried under a stream of nitrogen gas.
Prior to each use, platinum foil was washed with water and flame
-
annealed using a butane torch for 10 s. CO
2
-
saturated potassium bicarbonate electrolyte (KHCO
3
, 0.1 M) was prepared by sparging an aqueous solution of
potassium carbonate (K
2
CO
3
, 0.05 M) with CO
2
for at least 1 h prior to electrolysis.
Synthesis of Diphenyliodonium Triflate
The synthesis of diphenyliodonium triflate was performed as reported.
1
The as
-
synthesized compound was
characterized by 1H NMR in d6
-
DMSO (400 MHz) δ(ppm): 8.26 (d, J = 7.0 Hz, 1H), 7.68 (t, J = 7.5 Hz, 1H), 7.54 (t, J =
7.8 Hz, 2H).
High throughput electrochemical testing
Prior to the electrolysis, the electrolyte (0.1 M KHCO
3
, ≥99.95% trace metals basis, Sigma Aldrich) with or without
additives was purged with CO
2
(99.999%, Airgas) for at least 30 min. A bipolar membrane (BPM, Fumasep® FBM
single film, Fumatech) was used to separate the working and counter electrodes. Platinum wire (99.9%, Sigma
Aldrich) was used as the counter electrode. Electrolysis was carried o
ut with a Gamry Reference 600TM potentiostat.
All electrochemical data were collected using a Ag/AgCl reference
electrode (LF2, Innovative Instruments) and
converted to a reversible hydrogen electrode (RHE) scale using the measured solution pH of 6.8. All cells and all
solution handling lines were purged with fresh electrolyte and CO
2
between electrolysis to avoid cross
-
contamination. The surface area of the counter electrodes were about 0.25 cm
2
, while the working electrode surface
areas were 0.32 cm
2
. The “fast
flow rate of electrolyte was 150 μL/s throughout the tests, and
slow
was 20 μL/s.
The electrode was h
eated using a Peltier element (Laird thermal) with a heat sink (by Digi Key) below it, which is
controlled by TEC
-
1161
-
4A
-
VIN1
-
SCREW Meerstetter TEC controller. Prior to each refill/experiment, the surface of
electrodes was preheated to the desired tempera
ture.
The electrolyte was not refilled into the cell until the software
(TEC service software) indicated the temperature was stabilized.
Analytical and Electro
-
chemistry (HT
-
ANEC) is an analytical
electrochemistry system previously published by our
group to efficiently detect a wide range of CO
2
R products.
2
At the end of each (photo)electrolysis, gaseous and liquid
products were sampled by the robotic sample handling system (RSHS) and analyzed by GC (Thermo Scientific
TRACE
1300) and HPLC (Thermo Scientific UltiMate 3000). Detailed product detection (method) can be found in
previous publications.
3,4
For any CO
2
reduction experiments with additives involved, the additives were pre
-
deposited at room temperature at the potential
-
1.2 V vs RHE for 7.5
min
in 0.1 M KHCO
3
with 10 mM
diphenyliodonium triflate and 10 mM of additive was also present in the 0.1 M KHCO
3
during electrocatalysis.
3
COMSOL Modeling Information
The governing equations for laminar flow and heat transfer in fluids were solved in COMSOL Multiphysics 6.1,
coupled by the nonisothermal flow interface. Buoyant effects were taken into account. The default solver
configurations were used with a relative t
olerance of 0.001. The modeling domain was discretized using an auto
-
generated extremely fine tetrahedral mesh with 2,020,386 elements. Inlet velocity boundary conditions were set to
fully developed flow and matched to experimental flow rates. The outlet w
as set to 0 Pa to constrain fluid pressure.
Inlet flow was set to room temperature and the electrode surface was set to experimental temperatures.
Parameter estimation for CO
2
reduction
We will follow the procedure of Limaye et al. for parameter estimation.
5
Specifically, using Bayesian inference, we
will generate distributions for parameters within a model given the raw data. The model we use is the following
model:
1
/
=
1
/
푙푖푚
+
1
/
푘푖푛푒푡푖푐
This model was used by Limaye et al. to represent mass transport limitations at high overpotentials, where
i
is the
total current,
푙푖푚
is the transport
-
limited current, and
푘푖푛푒푡푖푐
is the true kinetic current. For the kinetic model, we
will use:
푘푖푛푒푡푖푐
=
/
푅푇
+
훼퐹퐸
/
푅푇
푙푛
(
푘푖푛푒푡푖푐
)
=
푙푛
(
)
/
푅푇
+
훼퐹퐸
/
푅푇
This is the Butler
-
Volmer model with temperature dependence included. Here,
is the activation energy
for the reaction,
is the ideal gas constant,
is the temperature,
is the transfer coefficient (the inverse of the Tafel
slope,
),
is the prefactor of the Arrhenius rate constant expression,
is Faraday’s constant, and
is the applied
potential versus RHE. Note that by construction, the potential is positive and higher potentials lead to higher currents.
A few important notes about this expression. (1) the prefactor,
A
, represents the product of multiple prefactors, rate
constants, and equilibrium constants in the case of a multi
-
step reaction where the rate
-
determining step is not the
first electron transfer. (2) Similarly, the activation energy,
, is not the activation energy of rate
-
determining step,
necessary, but instead represents a sum of all the Arrhenius expressions that go into the rate constant pre
-
factor,
including the Gibbs free energies for equilibrium reactions before the rate
-
determi
ning step. (3) the potential is
shown as relative to RHE, but in practice could be shown as relative to any reference; the only thing that changes will
be the exact value of the activation energy, modified by
푟푒푓푒푟푒푛푐푒
. Thus, the activation energy reported is actually a
function of reference chosen for the system. In the case where the rate
-
determining step is the first elementary
reaction in a multi
-
step reaction, then the activation energy and the prefactor correspond
to the expected values for
an elementary step.
We can now modify the above expression with some math to get:
푙푛
(
)
=
푙푛
(
푙푖푚
)
+
푙푛
(
푘푖푛푒푡푖푐
)
푙푛
(
푙푖푚
+
푘푖푛푒푡푖푐
)
푙푛
(
)
=
푙푛
(
푙푖푚
)
+
푙푛
(
)
/
푅푇
+
훼퐹퐸
/
푅푇
푙푛
(
푙푖푚
+
/
푅푇
+
훼퐹퐸
/
푅푇
)
Numerically, fitting this can cause problems, so instead we will fit a variation:
푙푛
(
푘푖푛푒푡푖푐
)
푙푛
(
0
)
=
푙푛
(
)
/
푅푇
+
훼퐹퐸
/
푅푇
[
푙푛
(
)
/
0
+
훼퐹
0
/
0
]
Essentially, we are now fitting a model where we have normalized the current by the “true” kinetic model. Of course,
we do not have the “true” kinetic model, so we instead will use reference potential, temperature, and current from
the experimental dataset
. Our kinetic model becomes:
푙푛
(
푘푖푛푒푡푖푐
)
푙푛
(
)
=
/
푅푇
+
훼퐹퐸
/
푅푇
[
/
0
,
푒푥푝
+
훼퐹
0
,
푒푥푝
/
0
,
푒푥푝
]
Here,
b
represents the
actual
kinetic current at the experimentally given reference potential and temperature
indicated. Doing this removes some of the arbitrariness from the potential reference and gives physical meaning to
the free parameter
b
instead of a pre
-
exponential factor
A
. Empirically, we found that this led to faster and more
reproducible fitting with Monte Carlo sampling of the distributions (full parameter fits and distributions Figure S
10
).
4
Figure S1
:
Electrolyte temperature profiles A) 3 cm past the outlet of the cell given variable surface heating
temperatures and B) inside the cell. C) Cross
-
sectional COMSOL image of HT
-
ANEC with a flow rate of 150 μL/s and
SH=60 °C shows decent agreement with experi
mentally derived values, as shown in table S1. In the inset is the
location of the thermocouple for the internal temperature measurements. D) A histogram describing the volume of
electrolyte exhibiting a temperature gradient within the cell.
Surface T
Expt
outlet
T
Expt
internal
T
<COMSOL> internal
COMSOL st
d
dev
25
25
25.0
25.0
0.0
0.0
34
25.4
28.6
29.5
0.9
0.9
43
26.2
33.7
34.1
1.9
0.4
50
26.4
36.2
37.8
2.6
1.6
60
27.2
38.8
43.2
3.6
4.4
80
29.1
46.3
53.9
5.6
7.
6
Table S1
: Comparison of experimental
outlet and
internal temperatures
with COMSOL values
. ∆ corresponds to the
difference between experimental and simulation temperatures. We expect the higher average temperature observed
at elevated temperatures
in our simulation is due to
insufficient equilibration time, as indicated by the positive slopes
for 60 and 80 °C
. Furthermore, the thermocouple is placed at the top of the cathodic chamber and will therefore read
cooler temperatures than the average, which considers the electrolyte closest to the heated electrode.
5
Figure S2:
Calibration of OCV versus bulk temperature. Measurements in 0.5 M KCl with 5 mM K
3
Fe(CN)
6
and 5 mM
K
4
Fe(CN)
6
using a platinum rotating disk electrode, with a platinum wire counter electrode, and a SCE reference
electrode.
Set T
25
34
43
50
60
OCV
BH
0.478
0.461
0.444
0.431
0.413
<OCV
fast
>
0.482 ± 0.000
0.465 ± 0.006
0.452 ± 0.005
0.444 ± 0.007
0.420 ± 0.000
<T
fast
>
22.5 ± 0.2
31.9 ± 3.2
39.0 ± 2.6
43.2 ± 3.6
55.9 ± 0.0
<OCV
slow
>
0.483 ± 0.001
0.464 ± 0.006
0.450 ± 0.005
0.440 ± 0.005
0.413 ± 0.003
<T
slow
>
22.1 ± 0.5
32.3 ± 3.0
39.8 ± 2.6
45.5 ± 2.5
59.6 ± 1.4
Table S2:
Open Circuit Voltage (OCV) measurements in 0.5 M KCl with 5 mM K
3
Fe(CN)
6
and 5 mM K
4
Fe(CN)
6
shown in Figure 2. BH corresponds to projected values based on a linear regression of data points shown in
F
igure
S2. All slow/fast values are the average of two data points.
6
Figure S3
: Zoomed out cyclic voltammograms (CVs) of A) surface
heating with fast electrolyte recirculation, B) bulk
heating with fast electrolyte recirculation, C) surface heating with slow electrolyte recirculation, and D) surface
heating with fast electrolyte recirculation in the presence of a molecular film (deposi
ted in the same way as otherwise
referred to in the text). Cyclic voltammograms were performed with 10 mM K
3
Fe(CN)
6
in CO
2
-
sparged 0.1 M KHCO
3
scanning at 100 mV/s from 0.5 V to
-
1 V vs Ag/AgCl with a gold working electrode, Pt counter electrode, and leakless
Ag/AgCl reference electrode. CVs were performed to establish a mass transport limited regime for subsequent
chronoamperometry experiments.
The small fluctuations in current observed are associated with the periodicity of
the barrels in the peristaltic pump pushing the electrolyte through the system.
7
Figure S4
: Chronoamperometry (CA) at
-
0.8 V vs Ag/AgCl for 2 minutes of A) surface heating with fast electrolyte
recirculation, B) bulk heating with fast electrolyte recirculation, C) surface heating with slow electrolyte
recirculation, and D) surface heating with
fast electrolyte recirculation in the presence of a molecular film (deposited
in the same way as otherwise referred to in the text). CAs were performed with 10 mM K
3
Fe(CN)
6
in CO
2
-
sparged 0.1
M KHCO
3
with a gold working electrode, Pt counter electrode, and leakless Ag/AgCl reference electrode. The average
current across the second minute was used in subsequent boundary layer calculations. The significant decrease in
activity with organic films may be
due to the inhibition of the transfer of ferricyanide through the film.
The small
fluctuations in current observed are associated with the periodicity of the barrels in the peristaltic pump pushing the
electrolyte through the system.
8
Figure S5:
Concentration boundary layer versus electrolyte recirculation flow rate. These experiments were
obtained according to section SI
-
4 from Clark et al.
6
Briefly, a CV is initially performed to determine the mass
transport limited regime, and then a potential is chosen for subsequent constant potential experiments to determine
the boundary layer at different recirculation rates. The boundary layer was calcu
lated using the inset equation,
wherein D
K3Fe(CN)6
is the diffusivity of the ferricyanide ion at 25 °C (0.72×10
-
5
cm
2
s
-
1
),
*[Fe(
퐶푁
)
6
3−
] is the
concentration of ferricyanide ion in the bulk of the electrolyte (10 mM), and j
SS
is the steady
-
state current density.
Figure S6
:
Calculated concentration boundary layer thickness at a 150 μL/s flow rate using surface temperatures
from Table S2 and temperature
-
adjusted diffusion coefficients
.
7
9
Figure S7:
Temperature versus resistance plots of surface heated (SH) versus bulk heated (BH) electrolyte using 0.1
M KHCO
3
.
10
Figure S8:
Plots of
Faradaic efficiencies for polycrystalline Cu CO
2
R at variable temperatures in 0.1 M KHCO
3
. Each
data point corresponds to an individual experiment.
Figure S9
: Partial current density towards electrochemical CO
2
reduction at variable temperatures in the absence of
molecular coating in 0.1 M KHCO
3
on polycrystalline Cu.
Each data point corresponds to an individual experiment.
11
Figure S10:
Partial current density towards electrochemical CO
2
reduction at variable temperatures in the absence
of molecular coating in 0.1 M KHCO
3
on polycrystalline Cu with an organic coating derived from diphenyliodonium
triflate.
Each data point corresponds to an individual experiment.
Figure S
1
1
:
Plots of Faradaic efficiencies for organic
-
modified polycrystalline Cu CO
2
R at variable temperatures in
0.1 M KHCO
3
. Each data point corresponds to an individual experiment.
12
Figure S12:
The reproducibility of C
2
H
4
partial current density
with 60 °C surface heating
and an uncompensated
applied potential of
-
1.27 V vs RHE
. Due to the cell resistance and variation of the total current density (3.
7
±
0.
3
mA cm
-
2
), the
resistance
-
compensated potential is slightly different for the
4 experiments
. Still,
the C
2
H
4
partial
current density
appears quite r
eproducible
mean and standard deviation of
0.86
± 0.
1
0
mA cm
-
2
.
To place these 4
repeat measurements in the context of the primary dataset,
the 3 nearby potentials with 60 °C surface heating are
also shown in the figure.
The C
2
H
4
partial current density
for this potential range is consistent across the data. The
4 repeat experiments were performed with a copy of the original electrochemical cell and a different lot of copper
foil.
We confirmed that the
reference
-
working resistance used for resistance compensation remains unchanged
from the cell used for the primary dataset.
We anticipate that the systematically lower electrochemical current
results from
subtle differences in the copper foil, which apparently are not very impactful for C
2
H
4
partial current
density.
The 4 repeat measurements show adequate reproducibility of the C
2
H
4
partial current density for a given
catalyst and condition, validating our
use of
Bayesian
modelling of the ensemble of electrochemical conditions
to
quantify uncertainty in
the temperature
-
dependent Tafel equatio
n
.
13
Figure S1
3
:
Fitting of
experimental CO
2
R data using
Tafel
kinetics (Equation 2 in the main text and full model
on SI
page 3
).
(A)
The
data points from experiments are shown along with the
fitted Tafel model, where the solid lines
correspond to the maximum likelihood Tafel parameters
.
The
shaded regions
illustrate
the
one
-
sigma confidence
interval of the fit given the posterior probability distribution functions of all parameters from the Bayesian model
.
(B
-
E)
The posterior probability distribution functions are shown for the activation energy (B), the transfer coefficient
(C), the limiting current (D), and the pre
-
factor (E). All variables and fit equations are defined above in full model
discussion.
14
Table S3:
Potentials, currents, temperatures, and Faradaic efficiencies of electrolyses reported herein.
T (°C)
[Additive]
(mM)
V vs RHE
J total
(mA/cm
2
)
H
2
CH
4
CO
C
2
H
4
EtOH
CHOOH
C
2+
Liq.
Total FE
25
-
-
0.86
-
2.23
37.0
1.2
1.7
0.9
0.0
0.0
0.0
40.8
25
-
-
0.90
-
2.36
52.2
0.7
3.1
0.6
0.0
0.0
0.0
56.6
25
-
-
0.95
-
2.77
48.0
1.5
5.1
1.2
0.0
0.0
0.0
55.9
25
-
-
1.00
-
5.06
42.6
8.7
2.9
3.4
0.0
0.0
1.7
59.2
25
-
-
1.01
-
7.00
38.2
14.9
3.5
5.4
1.5
0.0
4.5
67.9
25
-
-
1.01
-
13.25
31.1
31.4
2.0
7.0
1.5
0.7
3.8
77.4
25
-
-
1.03
-
8.39
17.4
26.6
1.1
10.7
4.7
0.8
7.7
68.9
25
-
-
1.05
-
10.10
30.7
29.4
2.8
6.5
1.6
0.5
4.8
76.3
25
-
-
1.07
-
11.56
18.3
22.9
0.7
6.0
3.7
0.5
5.3
57.4
25
10
-
0.96
-
1.99
13.4
0.4
7.9
16.8
20.7
0.0
0.0
59.2
25
10
-
1.02
-
4.21
12.4
0.3
4.0
21.4
18.2
0.0
1.6
57.9
25
10
-
1.06
-
7.22
17.6
0.7
2.8
31.6
10.9
0.0
0.5
64.2
25
10
-
1.07
-
7.08
11.3
1.0
2.2
32.4
15.8
9.2
3.7
75.5
25
10
-
1.08
-
11.39
18.1
4.1
1.4
25.8
19.2
0.0
1.4
70.1
25
10
-
1.12
-
9.63
18.1
1.4
1.8
31.7
24.8
0.0
3.7
81.6
25
10
-
1.12
-
14.76
19.3
5.0
1.5
28.5
17.8
0.0
1.3
73.5
34
10
-
0.95
-
2.52
13.0
0.1
7.2
16.0
2.8
7.9
0.0
47.1
34
10
-
1.01
-
4.84
16.2
0.5
5.0
21.5
7.2
14.8
4.4
69.6
34
10
-
1.04
-
8.46
15.8
0.8
3.0
25.4
13.4
6.6
3.7
68.7
34
10
-
1.09
-
11.22
23.1
2.0
1.9
27.5
15.3
3.0
1.3
74.1
34
10
-
1.16
-
12.66
29.8
2.7
1.5
23.2
13.0
2.1
1.3
73.5
43
-
-
0.88
-
4.18
48.5
0.9
2.1
0.8
0.0
28.2
0.0
80.5
43
-
-
0.89
-
3.31
42.2
1.1
3.3
1.4
0.0
42.3
0.8
91.1
43
-
-
0.92
-
4.74
52.0
0.6
3.5
0.7
0.0
24.5
0.0
81.4
43
-
-
0.94
-
3.55
54.5
0.8
4.5
1.5
0.0
42.4
1.1
104.7
43
-
-
0.98
-
5.34
39.5
3.8
5.8
4.2
0.7
29.4
5.9
89.3
43
-
-
1.00
-
5.96
52.1
5.1
6.0
4.0
0.0
33.4
0.0
100.7
43
-
-
1.00
-
5.81
44.4
3.7
5.0
4.2
0.0
29.5
1.2
88.2
43
-
-
1.01
-
11.50
33.6
15.7
4.2
10.4
2.2
9.0
10.0
85.0
43
-
-
1.02
-
16.81
30.3
25.3
2.6
10.9
2.0
9.8
7.1
88.0
43
-
-
1.02
-
10.44
27.0
18.7
3.2
16.0
4.7
14.3
12.2
96.0
43
-
-
1.04
-
15.46
29.9
23.5
2.5
12.9
3.4
21.1
8.6
101.9
43
-
-
1.04
-
12.40
30.1
18.9
3.3
9.5
2.9
19.4
8.2
92.3
43
10
-
0.90
-
2.78
11.2
0.1
8.2
9.3
3.2
20.8
2.2
55.1
43
10
-
0.93
-
3.59
14.2
0.1
8.5
13.8
4.1
13.1
1.4
55.3
43
10
-
0.98
-
6.14
15.0
0.3
6.0
24.0
7.3
13.2
6.5
72.2
43
10
-
1.02
-
9.57
17.4
0.8
2.8
26.8
13.8
6.1
3.3
71.0
43
10
-
1.07
-
12.29
19.9
1.4
2.5
27.4
15.9
4.1
3.5
74.7
43
10
-
1.13
-
14.12
28.9
2.7
1.9
27.1
14.9
1.6
1.4
78.5
50
10
-
0.91
-
2.21
10.7
0.2
10.8
13.1
5.3
19.4
2.5
61.8
50
10
-
0.93
-
3.77
10.9
0.1
7.5
13.1
5.8
12.2
4.9
54.4
50
10
-
0.98
-
7.57
19.1
0.1
7.5
17.6
7.8
11.9
4.5
68.7
50
10
-
1.02
-
11.79
24.0
0.2
4.4
21.5
12.9
6.7
7.3
77.1
50
10
-
1.02
-
9.25
14.4
0.7
3.2
26.6
16.9
6.7
7.0
68.8
50
10
-
1.03
-
10.89
21.3
0.2
4.9
21.0
12.6
7.3
7.3
74.4
50
10
-
1.03
-
10.86
22.3
0.1
4.9
21.8
13.3
7.7
6.2
76.4
50
10
-
1.05
-
12.54
21.1
0.2
4.0
25.4
13.5
3.6
5.4
73.1
15
50
10
-
1.07
-
12.12
13.8
0.6
2.0
20.5
16.9
5.9
4.8
64.5
50
10
-
1.09
-
11.16
15.5
0.9
3.0
20.4
14.3
7.4
6.7
60.7
50
10
-
1.10
-
15.86
35.8
1.9
1.3
20.0
14.2
1.9
3.1
78.2
60
-
-
0.89
-
3.95
40.9
0.4
2.4
0.9
0.0
0.0
0.0
44.6
60
-
-
0.89
-
3.73
47.8
1.0
1.9
1.2
0.0
0.0
0.0
51.9
60
-
-
0.92
-
4.85
58.0
0.5
4.4
0.9
0.0
0.0
0.0
63.8
60
-
-
0.93
-
4.24
52.2
0.4
3.9
0.8
0.0
0.0
0.0
57.3
60
-
-
0.96
-
5.46
54.1
0.4
4.5
0.9
0.0
0.0
0.0
59.9
60
-
-
0.98
-
6.23
44.6
2.7
5.3
3.9
1.2
0.3
3.6
61.6
60
-
-
0.99
-
7.28
50.8
3.6
6.1
4.1
0.7
0.6
4.5
70.4
60
-
-
0.99
-
6.78
50.7
1.4
5.3
2.4
0.0
0.0
0.0
59.8
60
-
-
1.00
-
6.67
51.4
2.2
4.0
2.9
0.0
0.0
3.1
63.6
60
-
-
1.02
-
11.14
29.3
8.6
4.1
13.4
3.9
1.6
12.6
73.4
60
-
-
1.05
-
15.73
32.7
13.6
2.8
11.0
3.0
1.3
10.0
74.5
60
-
-
1.06
-
12.18
42.2
16.7
5.0
12.3
1.7
0.7
7.6
86.2
60
-
-
1.09
-
13.38
34.3
18.8
4.0
9.4
1.6
0.2
4.5
72.8
60
10
-
0.89
-
3.24
10.0
0.1
10.0
9.3
4.2
18.1
4.2
55.8
60
10
-
0.91
-
4.53
8.2
0.0
7.6
9.9
5.8
5.0
8.2
44.7
60
10
-
0.96
-
7.31
12.4
0.1
7.1
20.2
6.4
8.6
5.3
60.1
60
10
-
1.00
-
10.56
15.4
0.2
3.8
23.6
15.1
8.0
6.8
73.0
60
10
-
1.02
-
14.96
19.8
0.6
2.6
22.2
16.0
4.3
6.0
71.6
60
10
-
1.06
-
15.32
20.7
0.4
4.0
21.7
12.5
3.9
5.1
68.3
80
10
-
0.98
-
8.57
16.3
0.1
8.1
13.9
5.9
9.0
7.6
60.8
80
10
-
1.01
-
13.88
24.6
0.1
4.7
19.6
10.4
5.8
5.6
70.8
80
10
-
1.09
-
15.24
25.7
0.1
4.2
13.3
8.5
12.7
5.4
69.8
80
10
-
1.11
-
14.36
24.3
0.1
5.0
16.5
9.0
5.1
6.2
66.2
80
10
-
1.11
-
17.98
38.3
0.3
3.9
15.3
8.6
4.7
3.3
74.3
16
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