Online Monitoring of Methanol Electro-Oxidation Reactions by Ambient Mass Spectrometry

Article abstract of DOI:10.1007/s13361-016-1450-9

Online detection of methanol electro-oxidation reaction products [e.g., formaldehyde (HCHO)] by mass spectrometry (MS) is challenging, owing to the high salt content and extreme pH of the electrolyte solution as well as the difficulty in ionizing the reac

Full text of DOI:10.1007/s13361-016-1450-9

B American Society for Mass Spectrometry, 2016
J. Am. Soc. Mass Spectrom. (2016)
DOI: 10.1007/s13361-016-1450-9
FOCUS: HONORING R. G. COOKS' ELECTION TO THE
NATIONAL ACADEMY OF SCIENCES: RESEARCH ARTICLE
Online Monitoring of Methanol Electro-Oxidation Reactions
by Ambient Mass Spectrometry
Si Cheng,1 Qiuhua Wu,1,2 Howard D. Dewald,1 Hao Chen1
1Center for Intelligent Chemical Instrumentation, Department of Chemistry and Biochemistry, Edison Biotechnology Institute,
Ohio University, Athens, OH 45701, USA
2College of Sciences, Agricultural University of Hebei, Baoding, Hebei 071001, China
Abstract. Online detection of methanol electro-oxidation reaction products [e.g.,
formaldehyde (HCHO)] by mass spectrometry (MS) is challenging, owing to the high
salt content and extreme pH of the electrolyte solution as well as the difficulty in
ionizing the reaction products. Herein we present an online ambient mass spectro-
metric approach for analyzing HCHO generated from methanol electro-oxidation,
taking the advantage of high salt tolerance of desorption electrospray ionization mass
spectrometry (DESI-MS). It was found that HCHO can be detected as
PhNHNH+=CH2 (m/z 121) by DESI after online derivatization with PhNHNH2. With
this approach, the analysis of HCHO from methanol electro-oxidation by MS was
carried out not only in acidic condition but also in alkaline media for the first time.
Efficiencies of different electrodes for methanol oxidation at different pHs were also evaluated. Our results show
that Au electrode produces more HCHO than Pt-based electrodes at alkaline pH, while the latter have higher
yields at acidic solution. The presented methodology would be of great value for elucidating fuel cell reaction
mechanisms and for screening ideal fuel cell electrode materials.
Keywords: Methanol electro-oxidation, Fuel cell, Electrochemistry, Mass spectrometry, Desorption electrospray
ionization
Received: 19 March 2016/Revised: 25 May 2016/Accepted: 10 July 2016
of magnitude greater than even highly compressed hydrogen,
and 15 times higher than lithium-ion batteries.
Introduction
fuel cell is an electrochemical device in which the chem-
ical energy stored in fuel is converted directly to electrical
The DMFCs rely on the oxidation of methanol on a catalyst
layer to form carbon dioxide. However, the electro-oxidation of
methanol often results in a variety of incomplete oxidation
products, such as formaldehyde (HCHO), formic acid
(HCOOH), methylformate (HCOOCH3), carbon monoxide
(CO), etc. [3, 4]. These byproducts can deactivate expensive
cell catalysts and thus the fuel cell itself. Many analytical
techniques, such as infrared spectroscopy [5], fluorescence
spectroscopy [6], and electrochemistry [7], were employed to
monitor the products resulting from the methanol electrochem-
ical oxidation reaction but they lack detection specificity. Mass
spectrometry (MS) can serve as a powerful detector for elec-
trochemical reactions with high sensitivity and selectivity since
MS can provide molecular weight and structural information
for redox reaction products or intermediates. Online coupling
of electrochemistry (EC) with MS has a history of over 40 y [8–
16]. In the past, differential electrochemical mass spectrometry
(DEMS) was adopted to monitor fuel cell reactions; however, it
A
energy through an electro-catalytic process. With the ever-
increasing demand for environmentally friendly energy
sources, fuel cells are considered as a promising energy tech-
nology. Currently, numerous research efforts are underway to
improve the performance of fuel cells, including development
of inexpensive catalysts [1, 2]. The strengths of direct methanol
fuel cells (DMFCs) are efficient fuel utilization, high energy-
dense, yet reasonably stable liquid fuel under all environmental
conditions. Indeed, the energy density of methanol is an order
Electronic supplementary material The online version of this article (doi:10.
1007/s13361-016-1450-9) contains supplementary material, which is available
to authorized users.
Correspondence to: Howard D. Dewald; e-mail: dewald@ohio.edu, Hao Chen;
e-mial: chenh2@ohio.edu

S. Cheng et al.: Methanol Electro-Oxidation
only can detect volatile and small molecules, such as CO2
and CO [17, 18], and is blind to byproducts, such as
HCHO, that cannot easily penetrate the membrane sepa-
rating the electrochemical cell and the mass spectrometer
vacuum chamber. Recent efforts were made to detect
HCHO using electrospray ionization mass spectrometry
(ESI) after extraction of methanol electro-oxidation prod-
ucts for removing the corrosive and nonvolatile sulfuric
acid that was used as electrolyte [4, 19]. Although the
method employed an elegant extraction strategy, it in-
volved complicated sample transfer processes, and the
extraction yield was not high (ca. 25%) [4, 19]. Further-
more, the previous mass spectrometric studies mainly
focused on monitoring methanol electrochemical oxida-
tion in acid media, not in alkaline solution. As alkaline
pH offers higher stability to fuel cell materials than
acidic pH [20], electrolysis of methanol in alkaline solu-
tion is receiving increased attention. Therefore, there is a
need for the development of a mass spectrometric ap-
proach that is fast, highly selective, and sensitive to
measure cell reaction products such as HCHO, at both
acidic and alkaline pHs [7].
In order to tackle this challenging problem, our strategy
is to use ambient mass spectrometry [21], such as desorp-
tion electrospray ionization mass spectrometry (DESI-MS)
[22], for the monitoring of HCHO from methanol electro-
oxidation. DESI is an important ionization method in the
MS field, and it has been introduced to provide direct
ionization of analytes with little or no sample preparation.
Besides analyzing solid samples from surfaces [21, 23–31],
DESI has been extended to directly ionize liquid samples,
ranging from small organics to high-mass proteins, in our
and other laboratories [9–11, 13, 14, 32–45]. In this study,
using DESI-MS to monitor HCHO generated from metha-
nol electro-oxidation has several advantages: (1) compared
with DEMS, the detection is convenient and performed at
ambient conditions rather than in vacuum; (2) there is no
requirement to separate the small potential applied to the
electrochemical cell from the high voltage used for DESI
spray, which is in contrast to the traditional EC/MS con-
figuration using an ESI interface. Therefore, the instrumen-
tation involved in this method for coupling the electro-
chemical cell with MS is simplified; (3) DESI is highly
tolerant to inorganic salt electrolytes, which is important to
the HCHO detection in the presence of the high salt-
content solution resulting from acid/base neutralization of
sulfuric acid or KOH used for methanol electro-oxidation.
The high concentration of salts is known to suppress signal
for ESI ionization [46]. We demonstrate that our DESI-MS
is a rapid method that can be used for online detection and
quantification of HCHO generated from methanol electro-
oxidation at both acidic and alkaline media, with no need
of sample extraction. In addition, the amount of HCHO
generated from different electrodes was evaluated and
compared, providing a novel platform for future electrolyt-
ic catalyst screening.
Experimental
Materials
HPLC-grade isopropanol, HPLC-grade acetonitrile,
phenylhydrazine, Nafion 117 solution (5% in a mixture of
low aliphatic alcohols and water), methanol, methanol-d1,
methanol-d4, methanol-13C, and formaldehyde-13C solution
were purchased from Sigma Aldrich. Sodium hydroxide and
potassium hydroxide were purchased from Fisher Chemicals,
Fair Lawn, NJ, USA and used without further purification. Pt/C
nanoparticle (50/50 wt%) was purchased from E-TEK Inc.,
Somerset, NJ, USA. The deionized water used for sample
preparation was obtained using a Nanopure Diamond
Barnstead purification system (Barnstead International, Du-
buque, IA, USA).
Preparation of Pt/C Electrode
Pt/C suspension was prepared by mixing and sonicating 8 mg
Pt/C powder, 4 mL of deionized water, 1 mL of isopropanol,
and 20 μL of Nafion 117 solution before use, following the
published procedure [7]. To prepare the thin-film working
electrode, 10 μL of Pt/C suspension was pipetted and then
dried on an Au disc electrode (i.d. 8 mm).
Online EC/DESI-MS Apparatus
A home-built DESI apparatus (Scheme 1) for coupling an elec-
trochemical cell with a Thermo Finnigan LCQ DECA MAX
ion trap mass spectrometer (San Jose, CA, USA) was used. The
electrochemical Reactor Cell was equipped with a working
electrode (WE), a counter electrode (carbon-loaded PTFE),
and a reference electrode (HyREF, a pseudo reference elec-
trode). In our experiment, different working electrodes including
a Pt disc electrode (i.d. 8 mm), an Au disc electrode (i.d. 8 mm),
and a Pt/C (50% wt) disc electrode were used to evaluate the
performance of different electrodes in producing HCHO from
electro-oxidation of methanol. A Roxy potentiostat (Antec BV,
Zoeterwoude, Nertherlands) was used to apply potential to the
cell for triggering methanol oxidation when the methanol sample
flowed through the cell. Sample solutions were prepared in
methanol/water containing 0.1 M sulfuric acid or 0.1 M KOH
as electrolyte and infused into the cell by a syringe pump for
electrolysis at a flow rate of 5 μL/min. The products from the cell
underwent online derivatization with 20 mM phenylhydrazine
introduced via a Tee mixer. The derivatized reaction products
were subsequently monitored by online DESI-MS.
DESI ionization occurs via interaction of sample with
charged microdroplets from the DESI spray; the resulting ions
were detected by the mass spectrometer. The DESI spray probe
was aimed at the sample capillary tip and kept 1–2 cm away
from the mass spectrometer inlet. The positive ion mode was
used for HCHO detection, the DESI spray solvent used was
ACN/H2O/1% HOAc at an injection flow rate of 10 μL/min,
and the nitrogen gas pressure for DESI spray was set to 160 psi.
For detection of HCHO generated from methanol oxidation in

S. Cheng et al.: Methanol Electro-Oxidation
Solvent
kV
N2
DESI spray
probe
Heated
capillary
.
.
..
..
. .
.
.
. .
MS
CE
-
Potentiostat
RE
PhNHNH2 in KOH (for MeOH oxidation in acid) or in H2SO4
(for MeOH oxidation in base)
+
WE
Scheme 1. Apparatus for online DESI-MS monitoring of methanol electro-oxidation in a thin-layer electrochemical flow cell
MeOH in H2SO4 or in KOH
sulfuric acid, the derivatizing reagent used was 20 mM
phenylhydrazine in 0.18 M NaOH solution infused at an injec-
tion flow rate of 5 μL/min. The final pH of the solution after
derivatization was around 2, which was beneficial to the deriv-
atization reaction. For detection of HCHO generated from
methanol oxidation in 0.1 M KOH, the derivatizing reagent
used was 20 mM phenylhydrazine in 0.06 M sulfuric acid
solution, which was infused at an injection flow rate of 5 μL/
min.
and finally CO2 [47, 48]. As the oxidation products emerge
from the cell, HCHO can be derivatized with phenylhydrazine
PhNHNH2 (Equation 2, Scheme 2) [4]. The resulting
hydrazone product PhNHN = CH2 can be ionized as the
protonated phenylhydrazone of m/z 121 by DESI for MS
detection.
In our experiment, a Pt disc WE (i.d. 8 mm) was chosen
first for testing. A solution containing 0.5 M methanol in
0.1 M sulfuric acid was introduced to the cell as the sample
solution. For detecting HCHO, phenylhydrazine was intro-
duced for HCHO derivatization. In addition, NaOH was
also doped in the phenylhydrazine solution for neutralizing
most of the sulfuric acid matrix (to ca. pH 2) as sulfuric
acid is highly corrosive to instruments. As shown in
Fig. 1a, when sample and derivatizing reagent were intro-
duced with no potential applied to the cell, no
phenylhydrazone product from HCHO derivatization reac-
tion was detected. When a 2.0 V potential was applied to
the cell, the peak of PhNHNH+=CH2 at m/z 121 arose
(Fig. 1b). This indicates that the methanol oxidation in
the cell produces incomplete oxidation product HCHO,
which can be detected by DESI-MS. Upon collision-
induced dissociation (CID), the ion of m/z 121 gave rise
to fragment ions m/z 93 and 94 by loss of CH2N. and
HCN, respectively, confirming its structure. Furthermore,
For quantification of HCHO, a formaldehyde-13C solu-
tion serving as an internal standard was introduced from
another Tee mixer to mix with the electrolyzed methanol
sample solution (see apparatus shown in Figure 4S,
Supporting Information) prior to derivatization with
phenylhydrazine. The derivatized reaction products were
monitored online by DESI-MS.
Results and Discussion
Monitoring Methanol Electro-Oxidation in Acidic
Conditions
Equation 1 of Scheme 2 shows the possible oxidation process
for methanol in which incomplete oxidation first produces
HCHO, which can be further oxidized into HCOOH, CO,
(a)
(eq. 1)
(b)
(eq. 2)
Scheme 2. Reactions showing (a) the proposed methanol electro-oxidation process, (b) the derivatization reaction of HCHO with
PhNHNH2

S. Cheng et al.: Methanol Electro-Oxidation
109
100
50
(a) MeOH in H2SO4, Cell off
a) Cell off
0
108
110
112
114
116
118
120
122
124
121
100
b) Cell on
NHNH CH2
(b) MeOH in H2SO4, Cell on
50
109
0
108
110
93
112
114
116
118
120
122
124
94
100
(c) CID of m/z 121
-CH2N.
- HCN
50
0
121
120
95
m/z
Fig. 1. DESI-MS spectra acquired when a solution of 0.5 M methanol in water containing 0.1 M sulfuric acid flowed through the fuel
cell using the Pt electrode with an applied potential of (a) 0.0 V and (b) 2.0 V; (c) CID MS/MS spectrum of the product ion
PhNHNH+=CH2 (m/z 121)
when methanol-13C was used to replace CH3OH, the prod-
uct ion PhNHNH+=13CH2 of m/z 122 was observed with
1 Da mass shift (Figure 1S, Supporting Information), con-
sistent with the product peak assignment. CID of m/z 122
shows the fragment ions m/z 93 and 94 by losses of
13CH2N. and H13CN, respectively, consistent with the as-
signment above. When CH3OH was replaced by CD3OD,
the corresponding product ion PhNHNH+=CD2 of m/z
123 was also detected (Figure 2S, Supporting Informa-
tion). Again, CID of m/z of 123 yields the fragment ions
m/z 93 and 95 by loss of CD2N. and DCN, respectively,
further confirming the ion structure. In comparison to the
previous reports of HCHO detection from methanol elec-
trochemical oxidation in 0.1 M sulfuric acid using ESI-
MS [4, 19], our method does not involve extra extraction
steps. Therefore, the instrumentation is simplified and the
analysis is faster.
In our experiment, the resulting sample solution contains
high salt (ca. 50 mM Na2SO4), which could suppress ion signal
for detection by traditional spray ionization methods. Indeed,
when traditional ESI-MS was used for ionizing the sample
solution, the protonated phenylhydrazone was hardly detected
(Figure 3S-a, Supporting Information). In contrast, the peak
was clearly observed by DESI (Fig. 1b) under similar experi-
mental conditions, suggesting the high salt tolerance of DESI
[37]. The absolute intensity of the peak of m/z 121 in ESI-MS
spectrum (4500, manufacturer arbitrary unit) was much lower
than that in the DESI-MS spectrum acquired on the same day
using the same experimental conditions (4,400,000, manufac-
turer arbitrary unit, Figure 3S-b in Supporting Information). In
this case, the time interval is about 1 min between the MS
detection of the HCHO signal and the start of the cell electrol-
ysis, which is much shorter than 7 min time delay reported in
the previous ESI-MS study [4, 19], owing to the need for extra
extraction process.
Monitoring Methanol Electro-Oxidation in Alkaline
Solution
Our DESI-MS also allows the monitoring of methanol
electro-oxidation in an alkaline condition. To date, a ma-
jority of the work related to direct methanol fuel cells was
conducted in acidic media while a few studies of methanol
oxidation in alkaline solutions were reported [49–51].
There are several advantages of oxidizing methanol elec-
trochemically at alkaline pH. First, it was shown that the
methanol oxidation yield is higher in alkaline solution
compared with that in acid media [49–51]. Second, better
oxygen reduction kinetics in alkaline solution than in acid-
ic environment was also found [20]. Third, an alkaline fuel
cell provides a wide selection of possible electrocatalysts
[20]. Owing to these existing advantages, it is necessary to
develop an analytical method for monitoring methanol
electro-oxidation in alkaline solution as well.
Figure 2 shows the result of the methanol oxidation in the
alkaline condition; 0.5 M MeOH in 0.1 M KOH was intro-
duced into the flow cell at a flow rate of 5 μL/min.
Phenylhydrazine in 0.06 M sulfuric acid was introduced to
derivatize the electrochemically generated HCHO (sulfuric
acid was added to neutralize the medium to approximately
pH 2). Without a potential applied on the cell, no protonated
phenylhydrazone was observed (Fig. 2a). When a 2.0 V

S. Cheng et al.: Methanol Electro-Oxidation
(a) MeOH in KOH, Cell off
(b) MeOH in KOH, Cell on
109
100
50
0
109
100
50
0
121
108
112
116
120
124
108
112
116
120
124
m/z
m/z
Fig. 2. DESI-MS spectra acquired when a solution of 0.5 M methanol in water containing 0.1 M KOH flowed through the fuel cell
using the Pt electrode with an applied potential of (a) 0 V and (b) 2V
potential was applied to the cell, a peak at m/z 121 correspond-
ing to the protonated phenylhydrazone was clearly seen, indi-
cating the formation of HCHO (Fig. 2b).
When the cell was applied with a 2.5 V potential, a peak at
m/z 135 corresponding to the protonated derivatization
product was observed, indicating the formation of
CH3CHO (Fig. 3b). Upon CID, the ion of m/z 135 gave
rise to fragment ions m/z 93, 94, 108, and 118 by loss of
CH3CH = N. and CH3CN, CH2 = CH. and NH3 respec-
tively, confirming its structure. To the best of our knowl-
edge, this result represents the detection of alcohol oxida-
tion products at alkaline pH by MS for the first time.
After successfully detecting HCHO from methanol
electro-oxidation in alkaline pH, we also tested the detec-
tion of acetaldehyde from ethanol electro-oxidation in al-
kaline pH. It was proposed that C2H5O- is the reactive
form of ethanol in alkaline solution and it is adsorbed to
form ethoxy on the Pt surface. The adsorbed ethoxy then is
oxidized to acetaldehyde [52]. Indeed, in our experiment,
the acetaldehyde could be detected. Figure 3 shows the
result of the ethanol oxidation in the alkaline condition;
0.5 M EtOH in 0.1 M KOH was introduced into the flow
cell at a flow rate of 5 μL/min. Phenylhydrazine in 0.06 M
sulfuric acid was introduced to derivatize the electrochem-
ically generated CH3CHO. Without a potential applied on
the cell, no derivatized product was observed (Fig. 3a).
Performance of Different Electrodes in Acidic
and Alkaline Conditions
After identifying HCHO from electrochemical oxidation of
methanol using Pt electrode in both acidic and alkaline condi-
tions, other electrodes such as Au electrode and Pt/C (50/50)
were also employed for comparison. The purpose of such an
Ethanol oxidation in KOH, cell off
(a)
109
100
50
0
100
105
110
109
115
120
125
130
135
(b) Ethanol oxidation in KOH, cell on
100
50
0
135
135
100
105
110
115
120
125
130
m/z
Fig. 3. DESI-MS spectra acquired when a solution of 0.5 M ethanol in water containing 0.1 M KOH flowed through the fuel cell using
the Pt electrode with an applied potential of (a) 0 V and (b) 2.5 V

S. Cheng et al.: Methanol Electro-Oxidation
experiment is to evaluate the electrocatalytic performance of
different electrodes for converting methanol into
formaldehyde.
the dead volume of the thin layer flow cell of 0.5 μL). Also,
another possible factor for low oxidation yield is a result of the
small electrode surface (the i.d. of the electrode disc used is
only 8 mm). Indeed, when the concentration of the injected
methanol was lowered to 0.1 M, a higher yield (4.4%) was
obtained. Although the yield is low, the success of HCHO
detection by DESI-MS reveals the high sensitivity of our
method. For industrial fuel cells, the yield would be signifi-
cantly higher because of the use of a larger electrode and longer
electrolysis time [4, 53]. We would expect a good utility of our
DESI-MS for real world analysis.
It can be seen from Fig. 4 that different electrodes have
different yields. The Au electrode has the lowest yield for
the formation of HCHO among three electrodes, whereas
the oxidation efficiency of Pt and Pt/C (50/50) electrodes
are comparable. This result is in line with a previous report
that Au electrode is usually considered as a poor catalyst
toward methanol oxidation in acidic condition [54]. It is
probably because Au has relatively weaker chemisorption
of methanol in acid than Pt or Pt-based catalysts [55]. Fig-
ure 4b shows the quantitative analysis result for methanol
oxidation at alkaline pH. Interestingly, the yield of HCHO
for MeOH oxidation for Au electrode is higher in alkaline
solution than that in acidic condition, whereas Pt and Pt/C
electrodes have relatively poorer yields of HCHO com-
pared with those in acidic conditions, which is in line with
the previous report [56]. It is likely that the Au electrode in
the alkaline environment is strongly covered with
For quantification of HCHO generated from methanol
electro-oxidation on different electrodes, a formaldehyde-
13C solution was used as internal standard. For example,
under acidic oxidation condition, 0.5 M MeOH in 0.1 M
sulfuric acid was infused to the flow cell for electrolysis at
3 μL/min. 1.0 mM formaldehyde-13C in 0.1 M sulfuric
acid was introduced via a Tee mixer at 3 μL/min to mix
with the oxidized methanol as it exited from the cell. The
mixed solution was derivatized using phenylhydrazine in
0.18 M NaOH that was introduced via another Tee mixer
at 6 μL/min. In this case, the electrochemically generated
HCHO and the internal standard H13CHO were detected at
m/z 121 and 122, respectively. The amount of HCHO
generated can be calculated based on the peak height ratio
of m/z 121 to m/z 122 and the known quantity of the
internal standard, in consideration that two formaldehyde
products would have a similar ionization efficiency be-
cause of structural similarity. The method was also used
for quantifying methanol electro-oxidation in alkaline so-
lution (detailed procedure is described in SI).
Figure 4a shows the HCHO yields from three different
electrodes under acidic condition. In general, the yields are
very low (<1%). It is likely that an excess amount of methanol
was used and the residence time for methanol in this electro-
chemical flow cell was short (ca. 5 s based on the flow rate and
(a) MeOH electro-oxidation in H2SO4
Pt
0.80%
0.70%
Pt/C
Au
0.60%
0.50%
0.40%
0.30%
0.20%
0.10%
0.00%
(b) MeOH electro-oxidation in KOH
Au
1.20%
1.00%
0.80%
0.60%
0.40%
0.20%
0.00%
Pt/C
Pt
Fig. 4. Yields of HCHO generated from methanol electro-oxidation using different electrodes: (a) Au, Pt, and Pt/C (50/50) in acidic
condition; (b) Au, Pt, and Pt/C (50/50) in alkaline condition

S. Cheng et al.: Methanol Electro-Oxidation
chemisorbed and partially hydrated OH− ions. The
adsorbed OH− can be oxidized to form MOH (where the
M means Au here), and MOH is oxidized further to pro-
duce MO [57]. The generation of the gold oxide [58] is an
important property of Au electrodes, which plays a key
role in enhancing the catalytic activity in alkaline solution
[59]. These results shown above suggest that our findings
for electrode oxidation efficiency are in good agreement
with previous literature reports.
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Conclusions
Analysis of HCHO generated from the methanol electro-
oxidation reaction is traditionally difficult, and this study pre-
sents an ambient DESI-MS approach to tackle this challenge,
for the first time. Our DESI-MS method is fast, has high salt
tolerance, and involves simple instrumentation, which can be
applicable for HCHO analysis from methanol electro-oxidation
in both acidic and basic conditions. Conversion yields by
different electrodes were evaluated and the results showed that
platinum-based catalysts produced more HCHO in acidic con-
dition than the Au catalyst, while the latter offered a higher
yield over the platinum group catalysts in alkaline condition.
The presented methodology would be valuable for elucidating
fuel cell reaction mechanisms and for screening ideal fuel cell
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Acknowledgments
Q.W. thanks the Program of Study Abroad for Young Teachers
by Agricultural University of Hebei. This work is supported by
NSF Career (CHE-1149367), NSF IDBR (CHE-1455554), and
Ohio University Technology Seed Fund (GR0017495.01.05).
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