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Author |
Jia, W.-Z.; Zhang, Q.-Z.; Wang, X.-F.; Song, Y.-H.; Zhang, Y.-Y.; Wang, Y.-N. |
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Title |
Effect of dust particle size on the plasma characteristics in a radio frequency capacitively coupled silane plasma |
Type |
A1 Journal article |
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Year |
2019 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
52 |
Issue |
1 |
Pages |
015206 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Compared with dust-free plasmas, the existence of dust particles in plasmas may greatly influence the plasma properties. such as the plasma density, electron temperature, sheath properties, electron energy distribution function (EEDF) as well as the heating mechanism. In this work, a 1D hybrid fluid/MC model has been developed to investigate the interaction between dust and plasma in a low-pressure silane discharge sustained in a radio frequency capacitively coupled plasma, in which we assume spherical dust particles with a given radius are generated by taking the sum of the production rate of Si2H4- and Si2H5- as the nucleation rate. From our simulation, the plasma may experience definite perturbation by dust particles with a certain radius (more than 50nm) with an increase in electron temperature first, which further induces a rapid rise in the positive and negative ion densities. Then, the densities begin to decline due to the gradual lack of sufficient seed electrons. In addition, as the dust radius increases, the high energy tails of the EEDFs will be enhanced for discharge maintenance, accompanied by a decline in the population of low-energy electrons in comparison with those of pristine plasma. Furthermore, an obvious bulk heating is observed apart from the a-mode and local field reversal heating. This may contribute to the enhanced bulk electric field (also called the drift field) as a result of electron depletion via the dust. In addition, large-sized dust particles that accumulate near the sheaths tend to form two stable density peaks with their positions largely influenced by the time-averaged sheath thickness. A detailed study of the effects of the external parameters, including pressure, voltage and frequency, on the spatial distribution of dust particles is also conducted. |
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Wos |
000448423800002 |
Publication Date |
2018-10-02 |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.588 |
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Call Number |
UA @ admin @ c:irua:155361 |
Serial |
5271 |
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Permanent link to this record |
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Author |
Razzokov, J.; Yusupov, M.; Cordeiro, R.M.; Bogaerts, A. |
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Title |
Atomic scale understanding of the permeation of plasma species across native and oxidized membranes |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
51 |
Issue |
36 |
Pages |
365203 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Cold atmospheric plasmas (CAPs) have attracted significant interest for their potential benefits in medical applications, including cancer therapy. The therapeutic effects of CAPs are related to reactive oxygen and nitrogen species (ROS and RNS) present in the plasma. The impact of ROS has been extensively studied, but the role of RNS in CAP-treatment remains poorly understood at the molecular level. Here, we investigate the permeation of RNS and ROS across native and oxidized phospholipid bilayers (PLBs) by means of computer simulations. The results reveal significantly lower free energy barriers for RNS (i.e. NO, NO2, N2O4) and O3 compared to hydrophilic ROS, such as OH, HO2 and H2O2. This suggests that the investigated RNS and O3 can permeate more easily through both native and oxidized PLBs in comparison to hydrophilic ROS, indicating their potentially important role in plasma medicine. |
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Wos |
000441182400002 |
Publication Date |
2018-08-08 |
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Series Editor |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
10 |
Open Access |
OpenAccess |
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Notes |
M Y gratefully acknowledges financial support from the Research Foundation—Flanders (FWO), grant 1200216N. The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. RMC thanks FAPESP and CNPq for financial support (grants 2012/50680-5 and 459270/2014-1, respectively). |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @c:irua:152824 |
Serial |
5005 |
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Permanent link to this record |
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Author |
Kumar, N.; Attri, P.; Dewilde, S.; Bogaerts, A. |
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Title |
Inactivation of human pancreatic ductal adenocarcinoma with atmospheric plasma treated media and water: a comparative study |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
51 |
Issue |
25 |
Pages |
255401 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In recent years, the interest in treating cancer cells with plasma treated media (PTM) and plasma treated water (PTW) has increased tremendously. However, the actions of PTM and PTW are still not entirely understood. For instance, it is not clear whether the action of PTM is due to a modification in proteins/amino acids after plasma treatment of the media, or due to reactive oxygen and nitrogen species (RONS) generated from the plasma, or a combination of both effects. To differentiate between the actions of RONS and modified proteins/amino acids on the treatment of cancer cells, we compared the effects of PTM and PTW on two different pancreatic ductal adenocarcinomas (MiaPaca-2, BxPc3) and pancreatic stellate cells
(PSCs) (hPSC128-SV). PSCs closely interact with cancer cells to create a tumor-promoting environment that stimulates local tumor progression and metastasis. We treated culture media and deionized water with a cold atmospheric plasma (CAP) jet, and subsequently applied this PTM/PTW at various ratios to the pancreatic cancer and PSC cell lines. We evaluated cell death, intracellular ROS concentrations and the mRNA expression profiles of four oxidative stress-related genes, i.e. Mitogen-activated protein kinase 7 (MAPK7), B-cell lymphoma 2 (BCL2), Checkpoint kinase 1 (CHEK1) and DNA damage-inducible transcript 3, also known as C/EBP homologous protein (CHOP). Our findings demonstrate that PTM and PTW have a similar efficacy to kill pancreatic cancer cells, while PTW is slightly more effective in killing PSCs, as compared to PTM. Furthermore, we observed an enhancement of the intracellular ROS concentrations in both pancreatic cancer cells and PSCs. Thus, it is likely that under our experimental conditions, the anti-cancer activity of PTM can be attributed more to the RONS present in the treated liquid, than to the modification of proteins/amino acids in the media. Furthermore, the fact that the chemo-resistant PSCs were killed by PTM/PTW may offer possibilities for new anti-cancer therapies for pancreatic cancer cells, including PSCs. |
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Wos |
000434266900001 |
Publication Date |
2018-06-04 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
We gratefully acknowledge financial support from the Research Foundation—Flanders (FWO) (grant number 12J5617N) and from the European Marie Skłodowska–Curie Individual Fellowship ‘Anticancer-PAM’ within Horizon2020 (grant number 743546). We also thank Atsushi Masamune (Division of Gastroenterology, Tohoku University Graduate School of Medicine, Sendai, Miyagi Prefecture, Japan) for providing us with human PSCs (hPSC128-SV) for this study. |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @c:irua:151962 |
Serial |
4997 |
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Permanent link to this record |
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Author |
Wang, W.; Berthelot, A.; Zhang, Q.; Bogaerts, A. |
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Title |
Modelling of plasma-based dry reforming: how do uncertainties in the input data affect the calculation results? |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
51 |
Issue |
20 |
Pages |
204003 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
One of the main issues in plasma chemistry modeling is that the cross sections and rate coefficients are subject to uncertainties, which yields uncertainties in the modeling results and hence hinders the predictive capabilities. In this paper, we reveal the impact of these uncertainties on the model predictions of plasma-based dry reforming in a dielectric barrier discharge. For this purpose, we performed a detailed uncertainty analysis and sensitivity study. 2000 different combinations of rate coefficients, based on the uncertainty from a log-normal distribution, are used to predict the uncertainties in the model output. The uncertainties in the electron density and electron temperature are around 11% and 8% at the maximum of the power deposition for a 70% confidence level. Still, this can have a major effect on the electron impact rates and hence on the calculated conversions of CO2 and CH4, as well as on the selectivities of CO and H2. For the CO2 and CH4 conversion, we obtain uncertainties of 24% and 33%, respectively. For the CO and H2 selectivity, the corresponding uncertainties are 28% and 14%, respectively. We also identify which reactions contribute most to the uncertainty in the model predictions. In order to improve the accuracy and reliability of plasma chemistry models, we recommend using only verified rate coefficients, and we point out the need for dedicated verification experiments. |
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Wos |
000430960600003 |
Publication Date |
2018-04-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
7 |
Open Access |
OpenAccess |
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Notes |
We acknowledge financial support from the Fund for Scientific Research Flanders (FWO) (Grant No. G.0383.16N) and the TOP-BOF project of the University of Antwerp. The calculations were carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @c:irua:151292 |
Serial |
4958 |
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Permanent link to this record |
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Author |
Yusupov, M.; Yan, D.; Cordeiro, R.M.; Bogaerts, A. |
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Title |
Atomic scale simulation of H2O2permeation through aquaporin: toward the understanding of plasma cancer treatment |
Type |
A1 Journal article |
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Year |
2018 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
51 |
Issue |
12 |
Pages |
125401 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Experiments have demonstrated the potential selective anticancer capacity of cold atmospheric plasmas (CAPs), but the underlying mechanisms remain unclear. Using computer simulations, we try to shed light on the mechanism of selectivity, based on aquaporins (AQPs), i.e. transmembrane protein channels transferring external H 2 O 2 and other reactive oxygen species, created e.g. by CAPs, to the cell interior. Specifically, we perform molecular dynamics simulations for the permeation of H 2 O 2 through AQP1 (one of the members of the AQP family) and the palmitoyl-oleoyl-phosphatidylcholine (POPC) phospholipid bilayer (PLB). The free energy barrier of H 2 O 2 across AQP1 is lower than for the POPC PLB, while the permeability coefficient, calculated using the free energy and diffusion rate profiles, is two orders of magnitude higher. This indicates that the delivery of H 2 O 2 into the cell interior should be through AQP. Our study gives a better insight into the role of AQPs in the selectivity of CAPs for treating cancer cells. |
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Wos |
000426378100001 |
Publication Date |
2018-02-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
7 |
Open Access |
OpenAccess |
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Notes |
MY gratefully acknowledges financial support from the Research Foundation—Flanders (FWO) via Grant No. 1200216N and a travel grant to George Washington University (GWU). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Super- computer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. Work at GWU was supported by the National Science Foundation, grant 1465061. RMC thanks FAPESP and CNPq for finan- cial support (Grant Nos. 2012/50680-5 and 459270/2014-1, respectively). |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @c:irua:149382 |
Serial |
4811 |
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Permanent link to this record |
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Author |
Adamovich, I.; Baalrud, S.D.; Bogaerts, A.; Bruggeman, P.J.; Cappelli, M.; Colombo, V.; Czarnetzki, U.; Ebert, U.; Eden, J.G.; Favia, P.; Graves, D.B.; Hamaguchi, S.; Hieftje, G.; Hori, M.; Kaganovich, I.D.; Kortshagen, U.; Kushner, M.J.; Mason, N.J.; Mazouffre, S.; Thagard, S.M.; Metelmann, H.-R.; Mizuno, A.; Moreau, E.; Murphy, A.B.; Niemira, B.A.; Oehrlein, G.S.; Petrovic, Z.L.; Pitchford, L.C.; Pu, Y.-K.; Rauf, S.; Sakai, O.; Samukawa, S.; Starikovskaia, S.; Tennyson, J.; Terashima, K.; Turner, M.M.; van de Sanden, M.C.M.; Vardelle, A. |
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Title |
The 2017 Plasma Roadmap: Low temperature plasma science and technology |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
50 |
Pages |
323001 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Journal of Physics D: Applied Physics published the first Plasma Roadmap in 2012
consisting of the individual perspectives of 16 leading experts in the various sub-fields of low temperature plasma science and technology. The 2017 Plasma Roadmap is the first update of a planned series of periodic updates of the Plasma Roadmap. The continuously growing interdisciplinary nature of the low temperature plasma field and its equally broad range of applications are making it increasingly difficult to identify major challenges that encompass all of the many sub-fields and applications. This intellectual diversity is ultimately a strength of the field. The current state of the art for the 19 sub-fields addressed in this roadmap demonstrates the enviable track record of the low temperature plasma field in the development of plasmas as an enabling technology for a vast range of technologies that underpin our modern society. At the same time, the many important scientific and technological challenges shared in this roadmap show that the path forward is not only scientifically rich but has the potential to make wide and far reaching contributions to many societal challenges. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Wos |
000405553800001 |
Publication Date |
2017-07-14 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
246 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @ c:irua:144626 |
Serial |
4629 |
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Permanent link to this record |
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Author |
Khalilov, U.; Bogaerts, A.; Hussain, S.; Kovacevic, E.; Brault, P.; Boulmer-Leborgne, C.; Neyts, E.C. |
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Title |
Nanoscale mechanisms of CNT growth and etching in plasma environment |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
50 |
Pages |
184001 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma-enhanced chemical deposition (PECVD) of carbon nanotubes has already been shown to allow chirality control to some extent. In PECVD, however, etching may occur simultaneously with the growth, and the occurrence of intermediate processes further significantly complicates the growth process.
We here employ a computational approach with experimental support to study the plasma-based formation of Ni nanoclusters, Ni-catalyzed CNT growth and subsequent etching processes, in order to understand the underpinning nanoscale mechanisms. We find that hydrogen is the dominant factor in both the re-structuring of a Ni film and the subsequent appearance of Ni nanoclusters, as well as in the CNT nucleation and etching processes. The obtained results are compared with available theoretical and experimental studies and provide a deeper understanding of the occurring nanoscale mechanisms in plasma-assisted CNT nucleation and growth. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Wos |
000398300900001 |
Publication Date |
2017-04-03 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
6 |
Open Access |
OpenAccess |
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Notes |
UK gratefully acknowledges financial support from the Research Foundation – Flanders (FWO), Belgium (Grant No. 12M1315N). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Centre VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. The authors also thank Prof A C T van Duin for sharing the ReaxFF code. |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @ c:irua:141918 |
Serial |
4533 |
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Permanent link to this record |
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Author |
Kong, L.; Wang, W.; Murphy, A.B.; Xia, G. |
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Title |
Numerical analysis of direct-current microdischarge for space propulsion applications using the particle-in-cell/Monte Carlo collision (PIC/MCC) method |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
16 |
Pages |
165203 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Microdischarges are an important type of plasma discharge that possess several unique characteristics, such as the presence of a stable glow discharge, high plasma density and intense excimer radiation, leading to several potential applications. The intense and controllable gas heating within the extremely small dimensions of microdischarges has been exploited in microthruster technologies by incorporating a micro-nozzle to generate the thrust. This kind of microthruster has a significantly improved specific impulse performance compared to conventional cold gas thrusters, and can meet the requirements arising from the emerging development and application of micro-spacecraft. In this paper, we performed a self-consistent 2D particle-in-cell simulation, with a Monte Carlo collision model, of a microdischarge operating in a prototype micro-plasma thruster with a hollow cylinder geometry and a divergent micro-nozzle. The model takes into account the thermionic electron emission including the Schottky effect, the secondary electron emission due to cathode bombardment by the plasma ions, several different collision processes, and a non-uniform argon background gas density in the cathode-anode gap. Results in the high-pressure (several hundreds of Torr), high-current (mA) operating regime showing the behavior of the plasma density, potential distribution, and energy flux towards the hollow cathode and anode are presented and discussed. In addition, the results of simulations showing the effect of different argon gas pressures, cathode material work function and discharge voltage on the operation of the microdischarge thruster are presented. Our calculated properties are compared with experimental data under similar conditions and qualitative and quantitative agreements are reached. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000398856300001 |
Publication Date |
2017-02-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
8 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.588 |
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Call Number |
UA @ lucian @ c:irua:143642 |
Serial |
4674 |
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Permanent link to this record |
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Author |
Verlackt, C.C.W.; Neyts, E.C.; Bogaerts, A. |
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Title |
Atomic scale behavior of oxygen-based radicals in water |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
50 |
Pages |
11LT01 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Cold atmospheric pressure plasmas in and in contact with liquids represent a growing field of research for various applications. Understanding the interactions between the plasma generated species and the liquid is crucial. In this work we perform molecular dynamics (MD) simulations based on a quantum mechanical method, i.e. density-functional based tight-binding (DFTB), to examine the interactions of OH radicals and O atoms in bulk water. Our calculations reveal that the transport of OH radicals through water is not only governed by diffusion, but also by an equilibrium reaction of H-abstraction with water molecules. Furthermore, when two OH radicals encounter each other, they either form a stable cluster, or react, resulting in the formation of a new water molecule and an O atom. In addition,
the O atoms form either oxywater (when in singlet configuration) or they remain stable in solution (when in triplet configuration), stressing the important role that O atoms can play in aqueous solution, and in contact with biomolecules. Our observations are in line with both experimental and ab initio results from the literature. |
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Corporate Author |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000415252400001 |
Publication Date |
2017-02-13 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
11 |
Open Access |
OpenAccess |
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Notes |
The authors thank Peter Bruggeman (University of Minnesota, USA) and Jan Benedikt (Ruhr-Universität Bochum, Germany) for the interesting discussions regarding the existence of O in aqueous solutions. Furthermore, they acknowledge financial support from the Fund for Scientific Research (FWO) Flanders (project number G012413N). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. |
Approved |
Most recent IF: 2.588 |
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|
Call Number |
PLASMANT @ plasmant @ c:irua:140845 |
Serial |
4420 |
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Permanent link to this record |
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Author |
Ozkan, A.; Bogaerts, A.; Reniers, F. |
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Title |
Routes to increase the conversion and the energy efficiency in the splitting of CO2by a dielectric barrier discharge |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
50 |
Pages |
084004 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Here, we present routes to increase CO2 conversion into CO using an atmospheric pressure dielectric-barrier discharge. The change in conversion as a function of simple plasma parameters, such as power, flow rate, but also frequency, on-and-off power pulse, thickness and the chemical nature of the dielectric, wall and gas temperature, are described. By means of an in-depth electrical characterization of the discharge (effective plasma voltage, dielectric voltage, plasma current, number and lifetime of the microdischarges), combined with infrared analysis of the walls of the reactor, optical emission spectroscopy for the gas temperature, and mass spectrometry for the CO2 conversion, we propose a global interpretation of the effect of all the experimental parameters on the conversion and efficiency of the reaction. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000395400700001 |
Publication Date |
2017-01-30 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
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|
ISSN |
0022-3727 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
28 |
Open Access |
OpenAccess |
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|
Notes |
The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Interuniversity Attraction Pole) program PSIPhysical Chemistry of Plasma–Surface Interaction financially supported by the Belgian Federal Office for Science Policy (BELSPO). A Ozkan would like to thank the financial support given by the Fonds David et Alice Van Buuren. |
Approved |
Most recent IF: 2.588 |
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Call Number |
PLASMANT @ plasmant @ c:irua:140093 |
Serial |
4415 |
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Permanent link to this record |
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Author |
Wang, W.; Kong, L.; Geng, J.; Wei, F.; Xia, G. |
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Title |
Wall ablation of heated compound-materials into non-equilibrium discharge plasmas |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
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Volume |
50 |
Issue |
7 |
Pages |
074005 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The discharge properties of the plasma bulk flow near the surface of heated compound-materials strongly affects the kinetic layer parameters modeled and manifested in the Knudsen layer. This paper extends the widely used two-layer kinetic ablation model to the ablation controlled non-equilibrium discharge due to the fact that the local thermodynamic equilibrium (LTE) approximation is often violated as a result of the interaction between the plasma and solid walls. Modifications to the governing set of equations, to account for this effect, are derived and presented by assuming that the temperature of the electrons deviates from that of the heavy particles. The ablation characteristics of one typical material, polytetrafluoroethylene (PTFE) are calculated with this improved model. The internal degrees of freedom as well as the average particle mass and specific heat ratio of the polyatomic vapor, which strongly depends on the temperature, pressure and plasma non-equilibrium degree and plays a crucial role in the accurate determination of the ablation behavior by this model, are also taken into account. Our assessment showed the significance of including such modifications related to the non-equilibrium effect in the study of vaporization of heated compound materials in ablation controlled arcs. Additionally, a two-temperature magneto-hydrodynamic (MHD) model accounting for the thermal non-equilibrium occurring near the wall surface is developed and applied into an ablation-dominated discharge for an electro-thermal chemical launch device. Special attention is paid to the interaction between the non-equilibrium plasma and the solid propellant surface. Both the mass exchange process caused by the wall ablation and plasma species deposition as well as the associated momentum and energy exchange processes are taken into account. A detailed comparison of the results of the non-equilibrium model with those of an equilibrium model is presented. The non-equilibrium results show a non-equilibrium region near the plasma-wall interaction region and this indicates the need for the consideration of the influence of the possible departure from LTE in the plasma bulk on the determination of ablation rate. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000394097200001 |
Publication Date |
2017-01-24 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0022-3727 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.588 |
Times cited |
19 |
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 2.588 |
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Call Number |
UA @ lucian @ c:irua:141965 |
Serial |
4702 |
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Permanent link to this record |
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Author |
Kadu, A.; van Leeuwen, T.; Batenburg, K.J. |
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Title |
CoShaRP : a convex program for single-shot tomographic shape sensing |
Type |
A1 Journal article |
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Year |
2021 |
Publication |
Inverse Problems |
Abbreviated Journal |
Inverse Probl |
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Volume |
37 |
Issue |
10 |
Pages |
105005 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We introduce single-shot x-ray tomography that aims to estimate the target image from a single cone-beam projection measurement. This linear inverse problem is extremely under-determined since the measurements are far fewer than the number of unknowns. Moreover, it is more challenging than conventional tomography, where a sufficiently large number of projection angles forms the measurements, allowing for a simple inversion process. However, single-shot tomography becomes less severe if the target image is only composed of known shapes. This paper restricts analysis to target image function that can be decomposed into known compactly supported non-negative-valued functions termed shapes. Hence, the shape prior transforms a linear ill-posed image estimation problem to a non-linear problem of estimating the roto-translations of the shapes. We circumvent the non-linearity by using a dictionary of possible roto-translations of the shapes. We propose a convex program CoShaRP, to recover the dictionary coefficients successfully. CoShaRP relies on simplex-type constraints and can be solved quickly using a primal-dual algorithm. The numerical experiments show that CoShaRP recovers shape stably from moderately noisy measurements. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000691743700001 |
Publication Date |
2021-07-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0266-5611 |
ISBN |
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Additional Links |
UA library record; WoS full record |
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Impact Factor |
1.62 |
Times cited |
|
Open Access |
OpenAccess |
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Notes |
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Approved |
Most recent IF: 1.62 |
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Call Number |
UA @ admin @ c:irua:181617 |
Serial |
6859 |
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Permanent link to this record |
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Author |
Sun, S.R.; Kolev, S.; Wang, H.X.; Bogaerts, A. |
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Title |
Coupled gas flow-plasma model for a gliding arc: investigations of the back-breakdown phenomenon and its effect on the gliding arc characteristics |
Type |
A1 Journal article |
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Year |
2017 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
26 |
Issue |
26 |
Pages |
015003 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We present a 3D and 2D Cartesian quasi-neutral plasma model for a low current argon gliding arc discharge, including strong interactions between the gas flow and arc plasma column.
The 3D model is applied only for a short time of 0.2 ms due to its huge computational cost. It mainly serves to verify the reliability of the 2D model. As the results in 2D compare well with those in 3D, they can be used for a better understanding of the gliding arc basic characteristics. More specifically, we investigate the back-breakdown phenomenon induced by an artificially controlled plasma channel, and we discuss its effect on the gliding arc characteristics. The
back-breakdown phenomenon, or backward-jump motion of the arc, as observed in the experiments, results in a drop of the gas temperature, as well as in a delay of the arc velocity with respect to the gas flow velocity, allowing more gas to pass through the arc, and thus increasing the efficiency of the gliding arc for gas treatment applications. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000419253000001 |
Publication Date |
2016-11-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
9 |
Open Access |
OpenAccess |
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Notes |
This work is financially supported by the Methusalem financing, by the Fund for Scientific Research Flanders (FWO) and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen. This work was also supported by the National Natural Science Foundation of China (Grant Nos. 11275021, 11575019). S R Sun thanks the financial support from the China Scholarship Council. |
Approved |
Most recent IF: 3.302 |
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Call Number |
PLASMANT @ plasmant @ c:irua:138993 |
Serial |
4337 |
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Permanent link to this record |
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Author |
Wang, W.; Berthelot, A.; Kolev, S.; Tu, X.; Bogaerts, A. |
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Title |
CO2 conversion in a gliding arc plasma: 1D cylindrical discharge model |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
065012 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
CO 2 conversion by a gliding arc plasma is gaining increasing interest, but the underlying mechanisms for an energy-efficient process are still far from understood. Indeed, the chemical complexity of the non-equilibrium plasma poses a challenge for plasma modeling due to the huge computational load. In this paper, a one-dimensional (1D) gliding arc model is developed in a cylindrical frame, with a detailed non-equilibrium CO 2 plasma chemistry set, including the CO 2 vibrational kinetics up to the dissociation limit. The model solves a set of time- dependent continuity equations based on the chemical reactions, as well as the electron energy balance equation, and it assumes quasi-neutrality in the plasma. The loss of plasma species and heat due to convection by the transverse gas flow is accounted for by using a characteristic frequency of convective cooling, which depends on the gliding arc radius, the relative velocity of the gas flow with respect to the arc and on the arc elongation rate. The calculated values for plasma density and plasma temperature within this work are comparable with experimental data on gliding arc plasma reactors in the literature. Our calculation results indicate that excitation to the vibrational levels promotes efficient dissociation in the gliding arc, and this is consistent with experimental investigations of the gliding arc based CO 2 conversion in the literature. Additionally, the dissociation of CO 2 through collisions with O atoms has the largest contribution to CO 2 splitting under the conditions studied. In addition to the above results, we also demonstrate that lumping the CO 2 vibrational states can bring a significant reduction of the computational load. The latter opens up the way for 2D or 3D models with an accurate description of the CO 2 vibrational kinetics. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000386605100002 |
Publication Date |
2016-10-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
3 |
Open Access |
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Notes |
This research was supported by the European Marie Skłodowska-Curie Individual Fellowship ‘GlidArc’ within Horizon2020 (Grant No. 657304) and by the FWO project (grant G.0383.16N). The calculations were performed using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UAntwerpen), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UAntwerpen. |
Approved |
Most recent IF: 3.302 |
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Call Number |
PLASMANT @ plasmant @ c:irua:135990 |
Serial |
4286 |
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Permanent link to this record |
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Author |
Wang, W.; Bogaerts, A. |
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Title |
Effective ionisation coefficients and critical breakdown electric field of CO2at elevated temperature: effect of excited states and ion kinetics |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
055025 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Electrical breakdown by the application of an electric field occurs more easily in hot gases than in cold gases because of the extra electron-species interactions that occur as a result of dissociation, ionization and excitation at higher temperature. This paper discusses some overlooked physics and clarifies inaccuracies in the evaluation of the effective ionization coefficients and the critical reduced breakdown electric field of CO2 at elevated temperature, considering the influence of excited states and ion kinetics. The critical reduced breakdown electric field is obtained by balancing electron generation and loss mechanisms using the electron energy distribution function (EEDF) derived from the Boltzmann transport equation under the two-term approximation. The equilibrium compositions of the hot gas mixtures are determined based on Gibbs free energy minimization considering the ground states as well as vibrationally and electronically excited states as independent species, which follow a Boltzmann distribution with a fixed excitation temperature. The interaction cross sections between electrons and the excited species, not reported previously, are properly taken into account. Furthermore, the ion kinetics, including electron–ion recombination, associative electron detachment, charge transfer and ion conversion into stable negative ion clusters, are also considered. Our results indicate that the excited species lead to a greater population of high-energy electrons at higher gas temperature and this affects the Townsend rate coefficients (i.e. of electron impact ionization and attachment), but the critical reduced breakdown electric field strength of CO2 is only affected when also properly accounting for the ion kinetics. Indeed, the latter greatly influences the effective ionization coefficients and hence the critical reduced breakdown electric field at temperatures above 1500 K. The rapid increase of the dissociative electron attachment cross-section of molecular oxygen with rising vibrational quantum number leads to a larger electron loss rate and this enhances the critical reduced breakdown electric field strength in the temperature range where the concentration of molecular oxygen is relatively high. The results obtained in this work show reasonable agreement with experimental results from literature, and are important for the evaluation of the dielectric strength of CO2 in a highly reactive environment at elevated temperature. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000385494000006 |
Publication Date |
2016-09-22 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
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Impact Factor |
3.302 |
Times cited |
3 |
Open Access |
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|
Notes |
Skłodowska-Curie Individual Fellowship ‘GlidArc’ within Horizon2020 (Grant No.657304) and the FWO project (grant G.0383.16N). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. |
Approved |
Most recent IF: 3.302 |
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Call Number |
PLASMANT @ plasmant @ c:irua:135515 |
Serial |
4281 |
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Permanent link to this record |
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Author |
Bogaerts, A.; Wang, W.; Berthelot, A.; Guerra, V. |
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Title |
Modeling plasma-based CO2conversion: crucial role of the dissociation cross section |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
055016 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma-based CO2 conversion is gaining increasing interest worldwide. A large research effort is devoted to improving the energy efficiency. For this purpose, it is very important to understand the underlying mechanisms of the CO2 conversion. The latter can be obtained by computer modeling, describing in detail the behavior of the various plasma species and all relevant chemical processes. However, the accuracy of the modeling results critically depends on the accuracy of the assumed input data, like cross sections. This is especially true for the cross section of electron impact dissociation, as the latter process is believed
to proceed through electron impact excitation, but it is not clear from the literature which excitation channels effectively lead to dissociation. Therefore, the present paper discusses the effect of different electron impact dissociation cross sections reported in the literature on the calculated CO2 conversion, for a dielectric barrier discharge (DBD) and a microwave (MW) plasma. Comparison is made to experimental data for the DBD case, to elucidate which cross section might be the most realistic. This comparison reveals that the cross sections proposed
by Itikawa and by Polak and Slovetsky both seem to underestimate the CO2 conversion. The cross sections recommended by Phelps with thresholds of 7 eV and 10.5 eV yield a CO2 conversion only slightly lower than the experimental data, but the sum of both cross sections overestimates the values, indicating that these cross sections represent dissociation, but most probably also include other (pure excitation) channels. Our calculations indicate that the choice of the electron impact dissociation cross section is crucial for the DBD, where this process is the dominant mechanism for CO2 conversion. In the MW plasma, it is only significant at pressures up to 100 mbar, while it is of minor importance for higher pressures, when dissociation proceeds mainly through collisions of CO2 with heavy particles. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000384030600001 |
Publication Date |
2016-08-31 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
57 |
Open Access |
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Notes |
The authors would like to thank R Snoeckx and S Heijkers for the interesting discussions. This research was supported by the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no. 606889, the European Marie Skłodowska-Curie Individual Fellowship project ‘GlidArc’ within Horizon2020, the FWO project (grant G.0383.16N), and the Network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7), supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. VG was partially supported by the Portuguese FCT— Fundação para a Ci |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:135070 |
Serial |
4111 |
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Permanent link to this record |
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Author |
Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Reniers, F.; Bogaerts, A. |
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Title |
DBD in burst mode: solution for more efficient CO2conversion? |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
055005 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
CO2 conversion into value-added products has gained significant interest over the few last years, as the greenhouse gas concentrations constantly increase due to anthropogenic activities. Here we report on experiments for CO2 conversion by means of a cold atmospheric plasma using a cylindrical flowing dielectric barrier discharge (DBD) reactor. A detailed comparison of this DBD ignited in a so-called burst mode (i.e. where an AC voltage is applied during a limited amount of time) and pure AC mode is carried out to evaluate their effect on the conversion of CO2 as well as on the energy efficiency. Decreasing the duty cycle in the burst mode from 100% (i.e. corresponding to pure AC mode) to 40% leads to a rise in the
conversion from 16–26% and to a rise in the energy efficiency from 15 to 23%. Based on a detailed electrical analysis, we show that the conversion correlates with the features of the microfilaments. Moreover, the root-mean-square voltage in the burst mode remains constant as a function of the process time for the duty cycles <70%, while a higher duty cycle or the usual pure AC mode leads to a clear voltage decay by more than 500 V, over approximately 90 s, before reaching a steady state regime. The higher plasma voltage in the burst mode yields a higher electric field. This causes the increasing the electron energy, and therefore their
involvement in the CO2 dissociation process, which is an additional explanation for the higher CO2 conversion and energy efficiency in the burst mode. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000403945500005 |
Publication Date |
2016-08-02 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
17 |
Open Access |
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|
Notes |
The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would also like to thank financial support given by ‘Fonds David et Alice Van Buuren’. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:134841 |
Serial |
4107 |
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Permanent link to this record |
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Author |
Bruggeman, P.J.; Kushner, M.J.; Locke, B.R.; Gardeniers, J.G.E.; Graham, W.G.; Graves, D.B.; Hofman-Caris, R.C.H.M.; Maric, D.; Reid, J.P.; Ceriani, E.; Fernandez Rivas, D.; Foster, J.E.; Garrick, S.C.; Gorbanev, Y.; Hamaguchi, S.; Iza, F.; Jablonowski, H.; Klimova, E.; Kolb, J.; Krcma, F.; Lukes, P.; Machala, Z.; Marinov, I.; Mariotti, D.; Mededovic Thagard, S.; Minakata, D.; Neyts, E.C.; Pawlat, J.; Petrovic, Z.L.; Pflieger, R.; Reuter, S.; Schram, D.C.; Schröter, S.; Shiraiwa, M.; Tarabová, B.; Tsai, P.A.; Verlet, J.R.R.; von Woedtke, T.; Wilson, K.R.; Yasui, K.; Zvereva, G. |
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Title |
Plasma–liquid interactions: a review and roadmap |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
5 |
Pages |
053002 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Plasma–liquid interactions represent a growing interdisciplinary area of research involving plasma science, fluid dynamics, heat and mass transfer, photolysis, multiphase chemistry and aerosol science. This review provides an assessment of the state-of-the-art of this multidisciplinary area and identifies the key research challenges. The developments in diagnostics, modeling and further extensions of cross section and reaction rate databases that are necessary to address these challenges are discussed. The review focusses on nonequilibrium plasmas. |
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Wos |
000384715400001 |
Publication Date |
2016-09-30 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1361-6595 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
460 |
Open Access |
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Notes |
This manuscript originated from discussions at the Lorentz Center Workshop ‘Gas/Plasma–Liquid Interface: Transport, Chemistry and Fundamental Data’ that took place at the Lorentz Center, Leiden University in the Netherlands from August 4, through August 8, 2014, and follow-up discussions since the workshop. All authors acknowledge the support of the Lorentz Center, the COST action TD1208 (Electrical Discharges with Liquids for Future Applications) and the Royal Dutch Academy of Sciences for their financial support. PJB, MJK, DBG and JEF acknowledge the support of the ‘Center on Control of Plasma Kinetics’ of the United States Department of Energy Office of Fusion Energy Science (DE-SC0001319). In addition, PJB and BRL acknowledge the support of the National Science Foundation (PHY 1500135 and CBET 1236225, respectively). In addition the enormous help of Mrs. Victoria Piorek (University of Minnesota) in the formatting of the final document including the references is gratefully acknowledged. |
Approved |
Most recent IF: 3.302 |
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Call Number |
PLASMANT @ plasmant @ c:irua:144654 |
Serial |
4628 |
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Permanent link to this record |
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Author |
Berthelot, A.; Bogaerts, A. |
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Title |
Modeling of plasma-based CO2conversion: lumping of the vibrational levels |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
045022 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Although CO2 conversion by plasma technology is gaining increasing interest, the
underlying mechanisms for an energy-efficient process are still far from understood. In this work, a reduced non-equilibrium CO2 plasma chemistry set, based on level lumping of the vibrational levels, is proposed and the reliability of this level-lumping method is tested by a self-consistent zero-dimensional code. A severe reduction of the number of equations to be solved is achieved, which is crucial to be able to model non-equilibrium CO2 plasmas by 2-dimensional models. Typical conditions of pressure and power used in a microwave plasma for CO2 conversion are investigated. Several different sets, using different numbers of lumped groups, are considered. The lumped models with 1, 2 or 3 groups are able to reproduce the gas temperature, electron density and electron temperature profiles, as calculated by the full model treating all individual excited levels, in the entire pressure range investigated. Furthermore, a 3-groups model is also able to reproduce the shape of the vibrational distribution function (VDF) and gives the most reliable prediction of the CO2 conversion. A strong influence of the vibrational excitation on the plasma characteristics is observed. Finally, the limitations of the lumped-levels method are discussed. |
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Wos |
000380380200036 |
Publication Date |
2016-07-08 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
33 |
Open Access |
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Notes |
This project has received funding from the European Union’s Seventh Framework Programme for research, technological development and demonstration under grant agreement no 606889 and it was also carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions—Interuniversity Attraction Poles, phase VII (PSI-IAP7) supported by the Belgian Science Policy Office (BELSPO). The computational work was carried out using the Turing HPC infrastructure at the CalcUA core facility of the Universiteit Antwerpen (UA), a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the UA. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:134397 |
Serial |
4101 |
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Permanent link to this record |
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Author |
Ozkan, A.; Dufour, T.; Bogaerts, A.; Reniers, F. |
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Title |
How do the barrier thickness and dielectric material influence the filamentary mode and CO2conversion in a flowing DBD? |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
045016 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
Dielectric barrier discharges (DBDs) are commonly used to generate cold plasmas at
atmospheric pressure. Whatever their configuration (tubular or planar), the presence of a dielectric barrier is mandatory to prevent too much charge build up in the plasma and the formation of a thermal arc. In this article, the role of the barrier thickness (2.0, 2.4 and 2.8 mm) and of the kind of dielectric material (alumina, mullite, pyrex, quartz) is investigated on the filamentary behavior in the plasma and on the CO2 conversion in a tubular flowing DBD, by means of mass spectrometry measurements correlated with electrical characterization and IR imaging. Increasing the barrier thickness decreases the capacitance, while preserving the electrical charge. As a result, the voltage over the dielectric increases and a larger number of microdischarges is generated, which enhances the CO2 conversion. Furthermore, changing the dielectric material of the barrier, while keeping the same geometry and dimensions, also affects the CO2 conversion. The highest CO2 conversion and energy efficiency are obtained for quartz and alumina, thus not following the trend of the relative permittivity. From the
electrical characterization, we clearly demonstrate that the most important parameters are the somewhat higher effective plasma voltage (yielding a somewhat higher electric field and electron energy in the plasma) for quartz, as well as the higher plasma current (and thus larger electron density) and the larger number of microdischarge filaments (mainly for alumina, but also for quartz). The latter could be correlated to the higher surface roughness for alumina and to the higher voltage over the dielectric for quartz. |
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Wos |
000380380200030 |
Publication Date |
2016-06-30 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
24 |
Open Access |
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Notes |
The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A. Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:134396 |
Serial |
4100 |
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Permanent link to this record |
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Author |
Trenchev, G.; Kolev, S.; Bogaerts, A. |
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Title |
A 3D model of a reverse vortex flow gliding arc reactor |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
035014 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this computational study, a gliding arc plasma reactor with a reverse-vortex flow stabilization is modelled for the first time by a fluid plasma description. The plasma reactor operates with argon gas at atmospheric pressure. The gas flow is simulated using the k-ε Reynolds-averaged Navier–Stokes turbulent model. A quasi-neutral fluid plasma model is used for computing the plasma properties. The plasma arc movement in the reactor is observed, and the results for the gas flow, electrical characteristics, plasma density, electron temperature, and gas temperature are analyzed. |
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Wos |
000376557400022 |
Publication Date |
2016-04-09 |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
20 |
Open Access |
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Notes |
This research was carried out in the framework of the network on Physical Chemistry of Plasma–Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO), and it was also funded by the Fund for Scientific Research Flanders (FWO). Grant number: 11U5316N. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:132888 c:irua:132888 |
Serial |
4063 |
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Permanent link to this record |
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Author |
Ozkan, A.; Dufour, T.; Silva, T.; Britun, N.; Snyders, R.; Bogaerts, A.; Reniers, F. |
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Title |
The influence of power and frequency on the filamentary behavior of a flowing DBD—application to the splitting of CO2 |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
025013 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this experimental study, a flowing dielectric barrier discharge operating at atmospheric pressure is used for the splitting of CO2 into O2 and CO. The influence of the applied frequency and plasma power on the microdischarge properties is investigated to understand their role on the CO2 conversion. Electrical measurements are carried out to explain the conversion trends and to characterize the microdischarges through their number, their lifetime,
their intensity and the induced electrical charge. Their influence on the gas and electrode temperatures is also evidenced through optical emission spectroscopy and infrared imaging. It is shown that, in our configuration, the conversion depends mostly on the charge delivered in the plasma and not on the effective plasma voltage when the applied power is modified. Similarly, at constant total current, a better conversion is observed at low frequencies, where a less filamentary discharge regime with a higher effective plasma voltage than that at a higher
frequency is obtained. |
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Wos |
000372337900015 |
Publication Date |
2016-02-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
40 |
Open Access |
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Notes |
The authors acknowledge financial support from the IAPVII/ 12, P7/34 (Inter-university Attraction Pole) program ‘PSI-Physical Chemistry of Plasma-Surface Interactions’, financially supported by the Belgian Federal Office for Science Policy (BELSPO). A Ozkan would like to thank the financial support given by ‘Fonds David et Alice Van Buuren’. N Britun is a postdoctoral researcher of the F.R.S.-FNRS, Belgium. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:131904 |
Serial |
4021 |
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Permanent link to this record |
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Author |
Belov, I.; Paulussen, S.; Bogaerts, A. |
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Title |
Appearance of a conductive carbonaceous coating in a CO2dielectric barrier discharge and its influence on the electrical properties and the conversion efficiency |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
015023 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
This work examines the properties of a dielectric barrier discharge (DBD) reactor, built for CO2 decomposition, by means of electrical characterization, optical emission spectroscopy and gas chromatography. The discharge, formed in an electronegative gas (such as CO2, but also O2), exhibits clearly different electrical characteristics, depending on the surface conductivity of the reactor walls. An asymmetric current waveform is observed in the metaldielectric (MD) configuration, with sparse high-current pulses in the positive half-cycle (HC) and a more uniform regime in the negative HC. This indicates that the discharge is operating in two alternating regimes with rather different properties. At high CO2 conversion regimes, a conductive coating is deposited on the dielectric. This so-called coated MD configuration yields a symmetric current waveform, with current peaks in both the positive and negative HCs. In a double-dielectric (DD) configuration, the current waveform is also symmetric, but without current peaks in both the positive and negative HC. Finally, the DD configuration with conductive coating on the inner surface of the outer dielectric, i.e. so-called coated DD, yields again an asymmetric current waveform, with current peaks in the negative HC. These different electrical characteristics are related to the presence of the conductive coating on the dielectric wall of the reactor and can be explained by an increase of the local barrier capacitance available for charge transfer. The different discharge regimes affect the CO2 conversion, more specifically, the CO2 conversion is lowest in the clean DD configuration. It is somewhat higher in the coated DD configuration, and still higher in the MD configuration. The clean and coated MD configuration, however, gave similar CO2 conversion. These results indicate that the conductivity of the dielectric reactor walls can highly promote the development of the high-amplitude discharge current pulses and subsequently the CO2 conversion. |
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Place of Publication |
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Wos |
000370974800030 |
Publication Date |
2016-01-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
25 |
Open Access |
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Notes |
The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7-PEOPLE-2013-ITN) under Grant Agreement № 606889 (RAPID—Reactive Atmospheric Plasma processIng—eDucation network). |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:130790 |
Serial |
4006 |
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Permanent link to this record |
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Author |
Van Laer, K.; Bogaerts, A. |
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Title |
Fluid modelling of a packed bed dielectric barrier discharge plasma reactor |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
25 |
Issue |
25 |
Pages |
015002 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
A packed bed dielectric barrier discharge plasma reactor is computationally studied with a fluid model. Two different complementary axisymmetric 2D geometries are used to mimic the intrinsic 3D problem. It is found that a packing enhances the electric field strength and electron temperature at the contact points of the dielectric material due to polarization of the beads by the applied potential. As a result, these contact points prove to be of direct importance to initiate the plasma. At low applied potential, the discharge stays at the contact points, and shows the properties of a Townsend discharge. When a high enough potential is applied, the plasma will be able to travel through the gaps in between the beads from wall to wall, forming a kind of glow discharge. Therefore, the inclusion of a so-called ‘channel of voids’ is indispensable in any type of packed bed modelling. |
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Wos |
000370974800009 |
Publication Date |
2015-12-01 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
50 |
Open Access |
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Notes |
The authors gratefully thank St Kolev for the many interesting discussions and the useful advise in setting up the models. This research was carried out in the framework of the network on Physical Chemistry of Plasma-Surface Interactions— Interuniversity Attraction Poles, phase VII (http://psi-iap7.ulb. ac.be/), and supported by the Belgian Science Policy Office (BELSPO). K Van Laer is indebted to the Institute for the Promotion of Innovation by Science and Technology in Flanders (IWT Flanders) for financial support. |
Approved |
Most recent IF: 3.302 |
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Call Number |
c:irua:129802 |
Serial |
3982 |
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Permanent link to this record |
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Author |
Kolev, S.; Bogaerts, A. |
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Title |
Similarities and differences between gliding glow and gliding arc discharges |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
24 |
Issue |
24 |
Pages |
065023 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this work we have analyzed the properties of a gliding dc discharge in argon at atmospheric pressure. Despite the usual designation of these discharges as ‘gliding arc discharges’, it was found previously that they operate in two different regimes—glow and arc. Here we analyze the differences in both regimes by means of two dimensional fluid modeling. In order to address different aspects of the discharge operation, we use two models—Cartesian and axisymmetric in a cylindrical coordinate system. The obtained results show that the two types of discharges produce a similar plasma column for a similar discharge current. However, the different mechanisms of plasma channel attachment to the cathode could produce certain differences in the plasma parameters (i.e. arc elongation), and this can affect gas treatments applications. |
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Place of Publication |
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Wos |
000368117100028 |
Publication Date |
2015-11-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
12 |
Open Access |
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Notes |
This work is financially supported by the Methusalem financing and by the IAP/7 (Inter-university Attraction Pole) program ‘Physical Chemistry of Plasma-Surface Interactions’ from the Belgian Federal Office for Science Policy (BELSPO). The work was carried out in part using the Turing HPC infrastructure of the CalcUA core facility of the Universiteit Antwerpen, a division of the Flemish Supercomputer Center VSC, funded by the Hercules Foundation, the Flemish Government (department EWI) and the Universiteit Antwerpen |
Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
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Call Number |
c:irua:129214 |
Serial |
3952 |
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Permanent link to this record |
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Author |
Peerenboom, K.; Parente, A.; Kozák, T.; Bogaerts, A.; Degrez, G. |
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Title |
Dimension reduction of non-equilibrium plasma kinetic models using principal component analysis |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
24 |
Issue |
24 |
Pages |
025004 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
The chemical complexity of non-equilibrium plasmas poses a challenge for plasma modeling because of the computational load. This paper presents a dimension reduction method for such chemically complex plasmas based on principal component analysis (PCA). PCA is used to identify a low-dimensional manifold in chemical state space that is described by a small number of parameters: the principal components. Reduction is obtained since continuity equations only need to be solved for these principal components and not for all the species. Application of the presented method to a CO2 plasma model including state-to-state vibrational kinetics of CO2 and CO demonstrates the potential of the PCA method for dimension reduction. A manifold described by only two principal components is able to predict the CO2 to CO conversion at varying ionization degrees very accurately. |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000356816200008 |
Publication Date |
2015-01-27 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
11 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
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Call Number |
c:irua:123534 |
Serial |
704 |
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Permanent link to this record |
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Author |
Kolev, S.; Bogaerts, A. |
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Title |
A 2D model for a gliding arc discharge |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
24 |
Issue |
24 |
Pages |
015025 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
In this study we report on a 2D fluid model of a gliding arc discharge in argon. Despite the 3D nature of the discharge, 2D models are found to be capable of providing very useful information about the operation of the discharge. We employ two modelsan axisymmetric and a Cartesian one. We show that for the considered experiment and the conditions of a low current arc (around 30 mA) in argon, there is no significant heating of the cathode surface and the discharge is sustained by field electron emission from the cathode accompanied by the formation of a cathode spot. The obtained discharge power and voltage are relatively sensitive to the surface properties and particularly to the surface roughness, causing effectively an amplification of the normal electric field. The arc body and anode region are not influenced by this and depend mainly on the current value. The gliding of the arc is modelled by means of a 2D Cartesian model. The arcelectrode contact points are analysed and the gliding mechanism along the electrode surface is discussed. Following experimental observations, the cathode spot is simulated as jumping from one point to another. A complete arc cycle is modelled from initial ignition to arc decay. The results show that there is no interaction between the successive gliding arcs. |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000348298200026 |
Publication Date |
2014-12-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
34 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
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Call Number |
c:irua:122538 c:irua:122538 c:irua:122538 c:irua:122538 |
Serial |
3 |
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Permanent link to this record |
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Author |
Kozák, T.; Bogaerts, A. |
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Title |
Evaluation of the energy efficiency of CO2 conversion in microwave discharges using a reaction kinetics model |
Type |
A1 Journal article |
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Year |
2015 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
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Volume |
24 |
Issue |
24 |
Pages |
015024 |
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Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
We use a zero-dimensional reaction kinetics model to simulate CO2 conversion in microwave discharges where the excitation of the vibrational levels plays a significant role in the dissociation kinetics. The model includes a description of the CO2 vibrational kinetics, taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is used to simulate a general tubular microwave reactor, where a stream of CO2 flows through a plasma column generated by microwave radiation. We study the effects of the internal plasma parameters, namely the reduced electric field, electron density and the total specific energy input, on the CO2 conversion and its energy efficiency. We report the highest energy efficiency (up to 30%) for a specific energy input in the range 0.41.0 eV/molecule and a reduced electric field in the range 50100 Td and for high values of the electron density (an ionization degree greater than 10−5). The energy efficiency is mainly limited by the VT relaxation which contributes dominantly to the vibrational energy losses and also contributes significantly to the heating of the reacting gas. The model analysis provides useful insight into the potential and limitations of CO2 conversion in microwave discharges. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
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Language |
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Wos |
000348298200025 |
Publication Date |
2014-12-23 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0963-0252;1361-6595; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.302 |
Times cited |
100 |
Open Access |
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Notes |
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Approved |
Most recent IF: 3.302; 2015 IF: 3.591 |
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Call Number |
c:irua:122243 |
Serial |
1087 |
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Permanent link to this record |
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Author |
Spadaro, M.C.; Luches, P.; Bertoni, G.; Grillo, V.; Turner, S.; Van Tendeloo, G.; Valeri, S.; D'Addato, S. |
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Title |
Influence of defect distribution on the reducibility of CeO2-x nanoparticles |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Nanotechnology |
Abbreviated Journal |
Nanotechnology |
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Volume |
27 |
Issue |
27 |
Pages |
425705 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
Ceria nanoparticles (NPs) are fundamental in heterogeneous catalysis because of their ability to store or release oxygen depending on the ambient conditions. Their oxygen storage capacity is strictly related to the exposed planes, crystallinity, density and distribution of defects. In this work a study of ceria NPs produced with a ligand-free, physical synthesis method is presented. The NP films were grown by a magnetron sputtering based gas aggregation source and studied by high resolution- and scanning-transmission electron microscopy and x-ray photoelectron spectroscopy. In particular, the influence of the oxidation procedure on the NP reducibility has been investigated. The different reducibility has been correlated to the exposed planes, crystallinity and density and distribution of structural defects. The results obtained in this work represent a basis to obtain cerium oxide NP with desired oxygen transport properties. |
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Address |
Dipartimento FIM, Universita di Modena e Reggio Emilia, via G. Campi 213/a, I-41125 Modena, Italy. CNR-NANO, via G. Campi 213/a, I-41125 Modena, Italy |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
English |
Wos |
000385483900004 |
Publication Date |
2016-09-15 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0957-4484 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.44 |
Times cited |
11 |
Open Access |
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Notes |
The authors gratefully acknowledge financial support by the Italian MIUR under grant FIRB RBAP115AYN (Oxides at the nanoscale: multifunctionality and applications). The activity is performed within the COST Action CM1104 'Reducible oxide chemistry, structure and functions'. The research leading to these results has received funding also from the European Union Seventh Framework Programme under Grant Agreement 312483—ESTEEM2 (Integrated Infrastructure Initiative–I3).; esteem2_ta |
Approved |
Most recent IF: 3.44 |
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Call Number |
EMAT @ emat @ c:irua:135424 |
Serial |
4130 |
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Permanent link to this record |
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Author |
Xu, W.; Peeters, F.M.; Devreese, J.T. |
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Title |
Normal and hot electro-phonon resonance effect in a quasi-two-dimensional semiconductor system |
Type |
A1 Journal article |
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Year |
1993 |
Publication |
Journal of physics : condensed matter |
Abbreviated Journal |
J Phys-Condens Mat |
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Volume |
5 |
Issue |
15 |
Pages |
2307-2320 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Theory of quantum systems and complex systems |
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Abstract |
The electro-phonon resonance effect is a consequence of a resonant interaction between two electric subbands mediated by an optical phonon. It occurs in a quasi-two-dimensional electron system each time the energy difference between two electric subbands equals the energy of a Lo phonon. We study the influence of this effect on the electron mobility by using the momentum balance equation. The temperature and electron density dependences of the resonances are studied in the linear and non-linear response regimes. |
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Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
A1993KX70100004 |
Publication Date |
2002-08-25 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0953-8984;1361-648X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.346 |
Times cited |
18 |
Open Access |
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Notes |
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Approved |
no |
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Call Number |
UA @ lucian @ c:irua:102984 |
Serial |
2367 |
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Permanent link to this record |