Nascent Soot Particle Size Distributions Measured Down to 1 nm

ARTICLE IN PRESSJID: PROCI [m;November 9, 2016;1:59]
Available online at www.sciencedirect.com
Proceedings of the Combustion Institute 000 (2016) 1–8
www.elsevier.com/locate/proci
Nascent soot particle size distributions down to 1 nm
from a laminar premixed burner-stabilized stagnation
ethylene flame
Quanxi Tang a,b,1
, Runlong Cai c,d,1
, Xiaoqing You a,b,∗
, Jingkun Jiang c,d,∗∗
a Center for Combustion Energy, Tsinghua University, Beijing 100084, China
b Key Laboratory for Thermal Science and Power Engineering of the Ministry of Education, Tsinghua University, Beijing
100084, China
c State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua
University, Beijing 100084, China
d State Environmental Protection Key Laboratory of Sources and Control of Air Pollution Complex, Beijing 100084, China
Received 4 December 2015; accepted 31 August 2016
Available online xxx
Abstract
In this study, spatially resolved measurement of soot particle size distribution functions (PSDFs) down to
∼1 nm from a laminar premixed burner-stabilized stagnation ethylene flame was made by paralleling a com-
mercial 3936 Scanning Mobility Particle Spectrometer (3936 SMPS) and a Diethylene Glycol (DEG) SMPS.
While the 3936 SMPS may detect particles with a mobility diameter of 3–150 nm, DEG SMPS can be used
to measure incipient soot particles of 1–10 nm. We found that the minimum diameter of the incipient soot
particles appeared at ∼1.5 nm (though with some uncertainty caused by the classification device). A complete
bimodality of the PSDFs was observed quantitatively when the burner-to-stagnation surface separation dis-
tance (Hp) was greater than 0.6 cm. Characterized by a lognormal distribution, the first peak appears to be
relatively stable at different Hp, with the geometric standard deviation varying from 1.1 to 1.3 and the peak
diameter ranging from 1.9 to 2.9 nm. The absolute number density of particles no bigger than the first peak
diameter was found to be positively related to the first peak diameter and the geometric mean diameter of
these particles.
© 2016 by The Combustion Institute. Published by Elsevier Inc.
Keywords: Soot inception; Premixed flame; 1–3 nm particles; SMPS; Bimodality
∗ Corresponding author at: Center for Combustion En-
ergy, Tsinghua University, Beijing 100084, China.
∗∗ Corresponding author at: State Key Joint Labora-
tory of Environment Simulation and Pollution Control,
School of Environment, Tsinghua University, Beijing
100084, China.
E-mail addresses: xiaoqing.you@tsinghua.edu.cn
(X. You), jiangjk@tsinghua.edu.cn (J. Jiang).
1 Quanxi Tang and Runlong Cai contributed equally to
this work and should be considered as co-first authors.
http://dx.doi.org/10.1016/j.proci.2016.08.085
1540-7489 © 2016 by The Combustion Institute. Published by Elsevier Inc.
Please cite this article as: Q. Tang et al., Nascent soot particle size distributions down to 1 nm from a
laminar premixed burner-stabilized stagnation ethylene flame, Proceedings of the Combustion Institute
(2016), http://dx.doi.org/10.1016/j.proci.2016.08.085

2 Q. Tang et al. / Proceedings of the Combustion Institute 000 (2016) 1–8
1. Introduction
Soot generated from combustion is of consid-
erable interest not only for its negative influence on
environment and human health, but also for a num-
ber of applications, such as carbon black for au-
tomobile tires and pigment in laser-printer toners,
all of which require a deep understanding of the
mechanism of soot formation. One of the biggest
challenges in this field of research is to understand
the process of nucleation and mass growth, espe-
cially for nascent soot particles below 10 nm in
flames.
Recent developments in experimental tech-
niques have paved way for a few studies on nascent
soot. The on-line dilution probe in conjunction
with the scanning mobility particle sizer (SMPS), in
particular, can follow the evolution of particle size
distribution functions (PSDFs) from nucleation to
mass growth for particles as small as 3 nm (if not
specially mentioned, all diameters are referred to
electrical mobility diameters). Based on this tech-
nique, previous studies [1–6] have indicated that the
premixed, lightly sooting ethylene flames are of bi-
modal characteristics at the region dominated by
both soot nucleation and mass growth. However,
the first peak was only partly observed because of
the 3 nm cutoff [7] in commercial SMPS such as
TSI 3936 used in these studies.
The 3 nm detection limit of commercial SMPS
has caused several problems. First, without quan-
titative information of the sub-3 nm particles, the
numerical simulations [1,2,6,8–10] with a detailed
gas-phase chemistry, nucleation and mass growth
model could not be completely validated. Secondly,
a previous study [10] indicated that the trough of
PSDFs was very sensitive to the size of the nuclei,
however a consensus about the size of the incipient
soot particles has not been reached in various
soot models. Mckinnon and Howard [11] made
an operational definition for the size of a soot
nucleus as 2000 amu and a projected area diameter
of ∼1.5 nm based on off-line transmission electron
microscopy observations. The smallest particle
with a volume diameter of 0.87 nm was used in
Ref. [2], while some nucleation models regarded the
pyrene–pyrene dimer as the minimum-sized parti-
cle with a volume diameter of ∼0.8 nm [1]. Singh
et al. [10], however, employed 224 carbon atoms,
corresponding to spherical particles of 1.68 nm
in volume diameter, to model the PSDFs, which
matched well with experimental data. Thirdly,
some experimental phenomena cannot be ob-
served because of the limitation from experimental
instruments. For example, the experimental results
in Refs. [12,13] indicate that the PSDFs will evolve
into an apparent unimodal distribution in particle
size larger than 3 nm in a high temperature flame,
but it is unclear whether the observed unimodal
distribution was affected by the instrument’s
detection limit.
While searching for solutions to the above-
mentioned problems, the interests on studying
particles smaller than 3 nm have continued over
the years. Sgro et al. [14] have attempted to fol-
low the gas to particle conversion process using
a differential mobility analyzer (DMA) and a
faraday cup electrometer (FCE). Based on their
observations, there were three peaks in the PSDFs
of the ethylene/air premixed flames at a sampling
height of 10 mm. Particle diameters at the first
and the second peaks of the PSDF were approx-
imately 0.8 and 2 nm, respectively. According to
their analysis, the first peak was attributable to
carbon compounds or molecular clusters in the
flame. Abid et al. [15] adopted a similar method to
investigate the premixed flat ethylene flames and
succeeded in extending the range of measurement
down to ∼1.9 nm. Different from the results re-
ported by Sgro et al. [14], minor drop-offs were
observed around 2.1 nm, but they were attributed
to inefficient non-steady state bipolar charging of
the instrument. For super 3 nm soot particles, the
measurement results obtained by FCE are com-
parable with those obtained by UCPC [15]. The
common problem of these FCE measurements is
that the results are interfered by charged molecular
clusters (ions) when measuring particles smaller
than 2.1 nm. In addition, FCE often suffers from
high background noises. Although nascent soot
particles smaller than 3 nm have been detected
with FCE, it is difficult to obtain quantitative
information due to these problems, and it remains
unclear how small the particles could be in the
fuel-rich premixed ethylene flames due to an am-
biguous boundary between the nascent soot and
the molecular clusters.
The lower detection limit of commercial SMPS
(∼3 nm) mentioned above is due to one of its com-
ponents, ultrafine condensation particle counter
(UCPC, TSI 3025 or 3776), which uses butanol as
the working fluid [7]. It can hardly activate particles
smaller than 3 nm because of the significant Kelvin
effect of these particles. Recent studies [16,17] sug-
gested that the working fluids with high surface
tension and low vapor pressure may overcome this
problem without causing homogenous nucleation.
Diethylene glycol (DEG) meets with these criteria.
UCPC using DEG as the working fluid has been
proved to be able to activate particles down to
∼1 nm [16,18–20]. Compared with FCE, DEG
UCPC has low background noise and can be tuned
to become insensitive to selected charged molecu-
lar clusters (ions) by adjusting the vapor saturation
ratio inside the activation/growth unit [18]. Based
on the new UCPC, DEG SMPS has been devel-
oped as a size spectrometer for sub-3 nm particles,
which has been successfully deployed in measuring
newly formed particles during atmospheric nu-
cleation events [18,19,21]. This new spectrometer
has not been used in any previous soot formation
studies.

Q. Tang et al. / Proceedings of the Combustion Institute 000 (2016) 1–8 3
Fig. 1. Schematic of experiment setup.
The purpose of this study is to expand the
soot particle detection limit down to 1 nm, obtain
detailed PSDFs in a burner-stabilized stagnation
ethylene flame using the burner-stabilized stagna-
tion probe together with the prototype DEG SMPS
and a commercial TSI 3936 SMPS, and analyze the
evolution of PSDFs, especially for sub-3 nm soot
particles.
2. Experimental
The experimental setup is presented in
Fig. 1. Similar to what was described in our
previous work [22,23], a laminar premixed flat
ethylene flame with an unburned composition of
14.4% (mol) ethylene, 21.6% (mol) oxygen and
64% (mol) argon (equivalence ratio, ϕ = 2) was
generated by a commercial McKenna burner with
a stainless outer layer and a 6 cm-diameter-bronze
water-cooled porous sintered plug. The cold gas
velocity was 7 cm/s (STP), which was controlled by
a sonic nozzle and calibrated by a BUCK soap-film
flow meter (Model M-30). The flame was shrouded
from the ambient air by a nitrogen flowing at
40 cm/s through a concentric porous plug.
The burner-stabilized stagnation flame configu-
ration was used to probe soot PSDFs. A sampling
tube made of stainless steel with an outer diameter
of 6.35 mm and wall thickness of 0.125 mm was
embedded in a 1.3 cm thick aluminum disc. The
flame gas containing soot particles was drawn
into the sampling probe through a 160 μm orifice,
which was cleaned by a fine stainless needle after
each scan because it can be easily clogged by soot
particles after sampling for a long time. Water
cooling copper coils were attached to the top of
the disc to avoid an excessively high temperature
of the disc. The temperature of the orifice was
measured by a type-K thermocouple imbedded in-
side of the aluminum disc. The orifice temperature
was about 436 ± 30 K when sampling. The burner-
to-stagnation surface separation distance Hp was
determined by a Vernier height gauge with an
accuracy of ± 0.02 cm. The flame temperature was
measured by a type-S thermocouple coated with
a Y/Be/O mixture to prevent surface catalytic re-
actions. The diameter of the thermocouple before
and after coating is 125 and 137 μm, respectively.
Radiation corrections were made using the proce-
dure of Shaddix [24], with gas mixture properties
calculated iteratively by a modified OPPDIF code
[25] using a detailed reaction model of USC-Mech
II [26]. The upper and lower temperature limits
were determined on the basis of the uncertainties
of emissivity of the coated thermocouple that
varies from 0.3 to 0.6 [27]. The radiation-corrected
temperature was assumed to be the average of the
two limiting values. The standard test of total num-
ber density as a function of dilution ratio was per-
formed with 3936 SMPS and DEG SMPS similarly
as in our previous work [23] and the results were
presented in Fig. S1 of the Supplemental material.
Two sets of SMPS were used to measure size
distributions of the diluted soot particles in paral-
lel. The first set is a TSI 3936 SMPS without any
modification, which has been used in our previ-
ous research [22,23]. Another set of DEG SMPS
was applied to measure 1–10 nm soot particles.
It consists of a neutralizer (TSI Model 3087), a
nanoDMA (TSI Model 3085), a DEG UCPC
(modified from TSI Model 3776), and a “booster”
CPC (TSI Model 3772). The sample flow rate of
the nanoDMA was 2 L/min, and the sheath flow
rate was 20 L/min. The sheath-to-aerosol ratio
is the same with that of the 3936 SMPS. The
temperatures of the saturator and the condenser
were set at 63 and 20 °C, respectively. 2 L/min of
classified monodisperse flow went into the DEG
UCPC, of which 0.25 L/min flowed through the
saturator after the particles were filtered and water
vapor was removed, and 0.05 L/min went directly

into the condenser as the capillary flow. Having
been activated by DEG, particles with a flow rate
of 0.3 L/min went into the CPC 3772 to further
grow into micrometer size range and got detected.
A filtered makeup flow of 0.7 L/min was applied
to match with the required inlet flow rate of CPC
3772. Compared with the 50% cut-off size, D50, of
2.5 nm of the UCPC 3776 or 3025, DEG UCPC
had a lower D50 of 1.4 nm. The detection efficiency
of 1.1 nm particles is ∼10%, which has been cali-
brated by negatively charged NaCl particles. The
maximum measurement range of DEG SMPS is
from 1 to 10 nm, which is divided into 30 bins.
Each scan cycle took 130 s, an up scan and a down
scan of 60 s each; and a zeroing time of 10 s. The
calibrated transport time between the nanoDMA
and the DEG-UCPC was 2.4 s. Up and down
scans agreed well at low soot concentrations. How-
ever, DEG UCPC needs several seconds to zero
after it measures extremely high concentrations
of particles. Therefore, only up scan data were
adopted to avoid the problem of zeroing instantly
after measuring extremely high concentrations
of soot particles in the down scan and to keep
the scan time consistent with that of 3936 SMPS.
Electrical mobility diameter was used in this study,
though the mobility-volume relationship has been
reported and can be readily applied [15,28].
Independent procedures were used to calculate
the soot particle number density, n(n=dN/dlog Dm,
where N is the number of particles and Dm is the
electrical mobility diameter) in the flames, which
was related to the number density measured by
3936 SMPS, n3936, and raw count data, nDEG, by
DEG SMPS. In regard to 3936 SMPS, the TSI
AIM software was used to obtain the inversed
data of n3936, while n is related to n3936 through the
following equation,
n = DR
n3936
ηdiff 3936
(1)
where DR is the dilution ratio; ηdiff3936 is the particle
diffusion loss factor in the sampling line between
the inlet of orifice and the impactor, which can
be calculated by the empirical equations provided
by Cheng et al. [29]. nDEG was recorded by a Lab-
VIEW program and inverted by a C++ program
to calculate number density, which is related to n
through a series of corrections including dilution,
charging, classification, activation, and diffusion
loss by Eq. (2).
n = DR
nDEG
ηch arg ing · ηDMA · ηDEG UCPC · ηdiff, DEG
(2)
where ηchrging is the charging fraction of particles.
Bipolar charging fraction was estimated using the
modified Fuchs theory [30]. Its uncertainty for sub-
3 nm particles needs to be addressed experimentally
in future study. ηDMA refers to the penetration of
the nanoDMA calculated by diffusional loss of
equivalent length method [31]. ηDEG UCPCis the
detection efficiency of DEG UCPC. ηdiff, DEG is the
diffusion loss in the sampling line from the inlet of
the sampling orifice to DEG UCPC.
3. Results and discussion
We measured the temperature profiles at several
burner-to-stagnation surface separations and made
radiation corrections using the method described
above. As shown in Fig. 2, the vertical error bars
represent the uncertainty of emissivity of the
coated thermocouple, which generates an approx-
imate ± 90 K uncertainty in peak temperatures.
The horizontal error bars are due to the position
uncertainty. The model predicted temperature
profiles agree well with the radiation-corrected
measured temperature profiles within experimental
uncertainties.
Figure 3 presents the PSDFs at several selected
representative burner-to-stagnation surface separa-
tion distances, Hp = 0.45–1.2 cm. The parameters’
effect of BSS flame technique on soot mobility have
been introduced in previous studies [23] and the
probe effect on measuring nascent soot particles
was discussed in [32]. The PSDFs measurements
were repeated at least three times for each position
with an average relative error of 14% and all
data from each measurement were included in
Fig. 3. As illustrated here, PSDFs are reproducible.
The DEG SMPS data agree well with the 3936
SMPS data at lower Hp (≤0.5 cm) for particles
bigger than 3 nm in diameter, but fewer particles
with a diameter of 6–10 nm at Hp ≥ 0.6 cm were
measured by the DEG SMPS than those by the
3936 SMPS. One possible deviation is due to the
uncertainty of charging fractions, since the 3936
SMPS classifies positively charged particles, while
the DEG SMPS classifies negatively charged ones
for higher detection efficiency [18].
As shown in Fig. 3, a distinctive peak at
∼2.4 nm mobility diameter can be observed for the
whole range of separation distances from 0.45 to
1.2 cm, which might be caused by the competition
of continuous nucleation and growth. A similar
peak has also been reported in Refs. [33,34] using
DMA (TapCon 3/150) equipped with a FCE if hy-
pothetically excluding the interference of ions. The
observation of this peak indicates that nucleation
does exist in the post-flame region, and the uni-
modality of PSDFs [12,13] of the high temperature
flames only represents part of the complete PSDF
due to the 3 nm cutoff limitation of the commercial
SMPS. While the smallest soot particles detected
by DEG SMPS appear at ∼1.5 nm and remains
nearly the same at different Hp, it does not mean
the smallest soot particles generated by nucleation
in the flame is 1.5 nm, as will be discussed later. It is
worthy to mention that the detection limit of DEG
UCPC was calibrated by particles with different
chemical compositions [16,18], and none of the

Fig. 2. Radiation-corrected temperature profiles. Symbols and lines are measured and simulated data, respectively.
Fig. 3. Evolution of PSDFs at different burner-to-stagnation separation distances. The open symbols are measured by the
DEG SMPS while the filled ones by the 3936 SMPS. Lines are fitting results. A lognormal distribution and a bi-lognormal
distribution are used as fitting functions at Hp = 0.45–0.55 cm, 0.6–1.2 cm, respectively. The dashed lines are drawn to
guide the eye.
detection efficiency was zero for 1.5 nm particles.
It is thus reasonable to believe that 1.5 nm is not
the detection limit of DEG UCPC. In addition,
the PSDFs of a fuel-lean flame and a slightly
fuel-rich flame (equivalence ratio ≤1.5) have been
measured. No signal was observed for these flames.
Considering that ions are ubiquitous in flames and
the detection efficiency of 1.47 nm tetra-heptyl
ammonium ion was less than 1% at the operated
conditions of DEG UCPC, we conclude that these
signals corresponding to ∼1.5 nm particles are not
caused by ions from the flame. Future work will
be performed to further explore the mechanism of
soot nucleation.

Fig. 4. A typical unimodal distribution of nascent soot
at Hp = 0.5 cm. Symbols are experimental data, and the
solid line is fitted to the data using a lognormal function.
The dash-dotted and dashed lines are theoretical transfer
functions of nanoDMA multiplied by a factor (see text) to
match with measured number density at 1.54 and 1.67 nm,
respectively.
Figure 3 indicates that the evolution of PSDFs
as a function of Hp experiences two different pro-
cesses: lognormal and bi-lognormal distributions.
At Hp = 0.45–0.5 cm, newly nucleated particles are
characterized by the lognormal distribution. As far
as the actual size of the smallest particles in flames
is concerned, despite the fact that the smallest par-
ticles detected by the DEG SMPS were ∼1.5 nm in
diameter, the real size might have been a little big-
ger than 1.5 nm due to the resolution limitation of
the nanoDMA used in this study. Figure 4 shows
the measured PSDF at Hp = 0.5 cm, and the theo-
retical transfer functions of nanoDMA [31] multi-
plied by a factor to match with the measured num-
ber density at 1.54 and 1.67 nm. Transfer function
is defined as the probability that an aerosol particle
which enters the mobility analyzer via the aerosol
inlet will leave via the sampling flow. A multiplica-
tive factor (n/ ∗
, where ∗
is the peak value of the
transfer function) was used in these transfer func-
tions. Whether particles smaller than 1.54 nm ex-
isted or not cannot be proved due to the diffusion
broadening effect in the nanoDMA, while the mea-
sured data points between 1.4 and 1.5 nm are signif-
icantly higher than the inverted number density us-
ing the transfer function of 1.67 nm, which suggests
that particles bigger than 1.67 nm surely existed in
the flame. Future work will be performed to reduce
the diffusion broadening effect by using a DMA of
higher resolution.
A sum of a power-law function and a lognor-
mal distribution function is usually used to fit the
PSDFs with mobility diameters larger than 3 nm
[35]. With these new sub-3 nm PSDFs data from
the DEG SMPS, the combined PSDFs have shown
a distinctively bi-lognormal form (the fitting equa-
tions can be found in supplemental material) at the
heights from 0.6 to 1.2 cm as shown in Fig. 3, which
Fig. 5. NT (absolute number density of particles no big-
ger than the first peak diameter), Dp (peak diameter at the
first peak), and Dgm (geometric mean diameter of parti-
cles no bigger than the first peak diameter) as a function
of burner-to-stagnation separation distance. Symbols are
the experimental data. Lines are drawn to guide the eye.
are the results of continuous nucleation, coagula-
tion, coalescence, and surface growth. However, at
Hp = 1.2 cm, particle nucleation became less dom-
inant and the number density at the first peak de-
creased by an order of magnitude compared with
that at Hp = 0.7 cm. At the same time, the second
peak of PSDF is wider, indicating that soot dynam-
ics has gradually changed due to a longer residence
time.
Figure 5 presents the absolute number density
of particles no bigger than the first peak diame-
ter, NT (obtained from integration of their number
density), the diameter at the first peak, Dp, and the
geometric mean diameter of these particles, Dgm.
As Hp gets higher, all three quantities NT, Dp, and
Dgm increase first and then decrease. The overall
trends of NT, Dp, and Dgm look similar, suggesting
Dp and Dgm are positively related with NT, which
makes sense because in theory a larger NT means
a higher collision frequency that usually leads to
larger particles at the first peak as well as larger ge-
ometric mean diameter, and vice versa. In fact, Dp
obtained at different HP in this study is similar to
that reported in Ref. [14] and the minor drop-off in
the number density in Ref. [15] using FCE is also
similar.
To understand the variation trend of peak
height and peak width of the measured PSDFs,
we present in Fig. 6 the geometric standard devia-
tions, σ, of the lognormal part of PSDFs as a func-
tion of separation distance, Hp. The values of σ at
the second peak increasing from 1.36 to 1.65 are
consistent with those in the study of Zhao et al.
[35]. The continuous upswing of σ at the second
peak at Hp = 1.2 cm corresponds to a visualized
change of size distributions, indicating a change in
particle dynamics, such as the formation of soot ag-
gregates. As a result of the competition of small

Fig. 6. Geometric standard deviations of the lognormal
part of PSDFs as a function of burner-to-stagnation sep-
aration distance.
particles generated by nucleation and those con-
sumed by surface growth and coagulation, the first
lognormal peak has smaller values of σ varying
from 1.14 to 1.32. As can be seen from Figs. 5 and
6, the trend of the diameter at the first peak of
the lognormal distribution and that of σ is simi-
lar, which is marginally different from those in Ref.
[34], keeping nearly constant at different separation
distances.
4. Conclusion
By expanding the lower detection limit down to
∼1 nm using a DEG SMPS, we observed a com-
plete bimodality in the size distribution of nascent
soot in a laminar burner-stabilized stagnation
premixed ethylene flame. The smallest particles
detected by the DEG SMPS in flame at different
separation distances appeared at ∼1.5 nm in di-
ameter, although only particles with a diameter
larger than 1.67 nm were sure to exist in the flame
with the nanoDMA. The diameter at the first peak
was ∼2.4 nm, which was affected by the absolute
number density of small particles. The increased
absolute number density led to a bigger Dp. The
geometric mean diameter of particles no bigger
than the first peak diameter has similar varia-
tions to those of the peak diameter. At a lower
burner-to-stagnation surface separation distance
(Hp = 0.45–0.55 cm), the flame was dominated by
nucleation, resulting in a lognormal distribution.
As Hp was increased, the bi-lognormal distribution
was observed because of the enhanced particle
coagulation.
Acknowledgment
Financially support from the National Key Ba-
sic Research and Development Program of China
(2013CB228502 and 2013CB228505), the National
Key Foundation for Exploring Scientific Instru-
ment of China (20121318549), the National Nat-
ural Science Foundation of China (91541122,
21221004, 41227805, and 21422703), and “Strate-
gic Priority Research Program” of the Chinese
Academy of Sciences (XDB05000000) are ac-
knowledged.
Supplementary materials
Supplementary material associated with this ar-
ticle can be found, in the online version, at doi:
10.1016/j.proci.2016.08.085.
References
[1] J. Appel, H. Bockhorn, M. Wulkow, Chemosphere 42
(5) (2001) 635–645.
[2] M. Balthasar, M. Kraft, Combust. Flame 133 (3)
(2003) 289–298.
[3] M.M. Maricq, S.J. Harris, J.J. Szente, Combust.
Flame 132 (3) (2003) 328–342.
[4] B. Zhao, Z. Yang, J. Wang, M.V. Johnston, H. Wang,
Aerosol Sci. Technol. 37 (8) (2003) 611–620.
[5] B. Öktem, M.P. Tolocka, B. Zhao, H. Wang,
M.V. Johnston, Combust. Flame 142 (4) (2005)
364–373.
[6] R. Lindstedt, B. Waldheim, Proc. Combust. Inst. 34
(1) (2013) 1861–1868.
[7] M.R. Stolzenburg, P.H. McMurry, Aerosol Sci. Tech-
nol. 14 (1) (1991) 48–65.
[8] H. Wang, M. Frenklach, Combust. Flame 110 (1)
(1997) 173–221.
[9] M. Balthasar, M. Frenklach, Proc. Combust. Inst. 30
(1) (2005) 1467–1475.
[10] J. Singh, R.I. Patterson, M. Kraft, H. Wang, Com-
bust. Flame 145 (1) (2006) 117–127.
[11] J.T. Mckinnon, J.B. Howard, Proc. Combust. Inst. 24
(1) (1992) 965–971.
[12] B. Zhao, Z. Yang, Z. Li, M.V. Johnston, H. Wang,
Proc. Combust. Inst. 30 (1) (2005) 1441–1448.
[13] A.D. Abid, N. Heinz, E.D. Tolmachoff, D.J. Phares,
C.S. Campbell, H. Wang, Combust. Flame 154 (4)
(2008) 775–788.
[14] L.A. Sgro, A. De Filippo, G. Lanzuolo, A.D Alessio,
Proc. Combust. Inst. 31 (1) (2007) 631–638.
[15] A. Abid, E. Tolmachoff, D. Phares, H. Wang,
Y. Liu, A. Laskin, Proc. Combust. Inst. 32 (1) (2009)
681–688.
[16] K. Iida, M.R. Stolzenburg, P.H. McMurry, Aerosol
Sci. Technol. 43 (1) (2009) 81–96.
[17] L.-E. Magnusson;, J.A. Koropchak;, M.P. Anisi-
mov;, V.M. Poznjakovskiy;, J.F. de la Mora, J. Phys.
Chem. Ref. Data 32 (4) (2003) 1387–1410.
[18] J. Jiang, M. Chen, C. Kuang, M. Attoui, P.H. Mc-
Murry, Aerosol Sci. Technol. 45 (4) (2011) 510–521.
[19] M. Chen, M. Titcombe, J. Jiang, et al., PNAS 109
(2012) 18713–18718.
[20] D. Wimmer, K. Lehtipalo, A. Franchin, et al., At-
mos. Meas. Technol. 6 (7) (2013) 1793–1804.
[21] J. Jiang, J. Zhao, M. Chen, et al., Aerosol Sci. Tech-
nol. 45 (4) (2011) ii–v.
[22] Q. Tang, J. Mei, X. You, Combust. Flame 165 (3)
(2016) 424–432.

[23] J. Camacho, C. Liu, C. Gu, et al., Combust. Flame
162 (10) (2015) 3810–3822.
[24] C.R. Shaddix, Correcting Thermocouple Measure-
ments for Radiation Loss: A Critical Review,,
Sandia National Labs, Livermore, CA, 1999 No.
CONF-990805.
[25] A.E. Lutz, R.J. Kee, J.F. Grcar, F.M. Rupley, OP-
PDIF: A Fortran Program for Computing Op-
posed-flow Diffusion Flames, Sandia National Lab-
oratories, Livermore, CA, 1997, pp. 96–8243. Sandia
Report.
[26] H. Wang, X. You, A.V. Joshi, S.G. Davis, A. Laskin,
F.N. Egolfopoulos, C.K. Law USC Mech Version
II. High-Temperature Combustion Reaction Model
of H2/CO/C1–C4 Compounds. Available at: http:
//ignis.usc.edu/USC_Mech_II.htm/, 2007.
[27] R. Peterson, N. Laurendeau, Combust. Flame 60 (3)
(1985) 279–284.
[28] C. Larriba;, C.J. Hogan;, M. Attoui;, R. Borrajo;,
J.F. Garcia;, J.F. de la Mora, Aerosol Sci. Technol. 45
(4) (2011) 453–467.
[29] Y.S. Cheng, P Kulkarni, P.A Baron, K Willeke,
Aerosol Measurement: Principles, Techniques, and
Applications Eds, WILEY, New York, 2011, p. 367.
[30] W.A. Hoppel, G.M. Frick, Aerosol Sci. 5 (1) (1986)
1–21.
[31] J. Jiang, M. Attoui, M. Heim, et al., Aerosol Sci.
Technol. 45 (4) (2011) 480–492.
[32] C. Saggese, A. Cuoci, A. Frassoldati, et al., Combust.
Flame 167 (2016) 184–197.
[33] M. Commodo, G. Tessitore, G. De Falco, A. Bruno,
P. Minutolo, A D’Anna, Proc. Combust. Inst. 35 (2)
(2015) 1795–1802.
[34] M. Commodo, G. De Falco, A. Bruno, C. Borriello,
P. Minutolo, A. D’Anna, Combust. Flame 162 (10)
(2015) 3854–3863.
[35] B. Zhao, Z. Yang, M.V. Johnston, et al., Combust.
Flame 133 (1) (2003) 173–188.

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