|
Records |
Links |
|
Author |
Kozák, T.; Bogaerts, A. |
|
|
Title |
Splitting of CO2 by vibrational excitation in non-equilibrium plasmas : a reaction kinetics model |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
|
|
Volume |
23 |
Issue |
4 |
Pages |
045004 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
We present a zero-dimensional kinetic model of CO2 splitting in non-equilibrium plasmas. The model includes a description of the CO2 vibrational kinetics (25 vibrational levels up to the dissociation limit of the molecule), taking into account state-specific VT and VV relaxation reactions and the effect of vibrational excitation on other chemical reactions. The model is applied to study the reaction kinetics of CO2 splitting in an atmospheric-pressure dielectric barrier discharge (DBD) and in a moderate-pressure microwave discharge. The model results are in qualitative agreement with published experimental works. We show that the CO2 conversion and its energy efficiency are very different in these two types of discharges, which reflects the important dissociation mechanisms involved. In the microwave discharge, excitation of the vibrational levels promotes efficient dissociation when the specific energy input is higher than a critical value (2.0 eV/molecule under the conditions examined). The calculated energy efficiency of the process has a maximum of 23%. In the DBD, vibrationally excited levels do not contribute significantly to the dissociation of CO2 and the calculated energy efficiency of the process is much lower (5%). |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000345761500014 |
Publication Date |
2014-06-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
170 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.302; 2014 IF: 3.591 |
|
|
Call Number |
UA @ lucian @ c:irua:117398 |
Serial |
3108 |
|
Permanent link to this record |
|
|
|
|
Author |
Biondo, O.; Hughes, A.; van der Steeg, A.; Maerivoet, S.; Loenders, B.; van Rooij, G.; Bogaerts, A. |
|
|
Title |
Power concentration determined by thermodynamic properties in complex gas mixtures : the case of plasma-based dry reforming of methane |
Type |
A1 Journal article |
|
Year |
2023 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
|
|
|
Volume |
32 |
Issue |
4 |
Pages |
045001-45020 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
We investigate discharge contraction in a microwave plasma at sub-atmospheric pressure, operating in CO2 and CO2/CH4 mixtures. The rise of the electron number density with plasma contraction intensifies the gas heating in the core of the plasma. This, in turn, initiates fast core-periphery transport and defines the rate of thermal chemistry over plasma chemistry. In this context, power concentration describes the overall mechanism including plasma contraction and chemical kinetics. In a complex chemistry such as dry reforming of methane, transport of reactive species is essential to define the performance of the reactor and achieve the desired outputs. Thus, we couple experimental observations and thermodynamic calculations for model validation and understanding of reactor performance. Adding CH4 alters the thermodynamic properties of the mixture, especially the reactive component of the heat conductivity. The increase in reactive heat conductivity increases the pressure at which plasma contraction occurs, because higher rates of gas heating are required to reach the same temperature. In addition, we suggest that the predominance of heat conduction over convection is a key condition to observe the effect of heat conductivity on gas temperature. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000963579500001 |
Publication Date |
2023-03-23 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.8 |
Times cited |
|
Open Access |
Not_Open_Access |
|
|
Notes |
|
Approved |
Most recent IF: 3.8; 2023 IF: 3.302 |
|
|
Call Number |
UA @ admin @ c:irua:196044 |
Serial |
8397 |
|
Permanent link to this record |
|
|
|
|
Author |
Martens, T.; Bogaerts, A.; Brok, W.J.M.; van Dijk, J. |
|
|
Title |
The dominant role of impurities in the composition of high pressure noble gas plasmas |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
|
Volume |
92 |
Issue |
4 |
Pages |
041504,1-3 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000252860400026 |
Publication Date |
2008-02-04 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.411 |
Times cited |
115 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.411; 2008 IF: 3.726 |
|
|
Call Number |
UA @ lucian @ c:irua:66820 |
Serial |
748 |
|
Permanent link to this record |
|
|
|
|
Author |
Chen, Z.; Bogaerts, A.; Vertes, A. |
|
|
Title |
Phase explosion in atmospheric pressure infrared laser ablation from water-rich targets |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Applied physics letters |
Abbreviated Journal |
Appl Phys Lett |
|
|
Volume |
89 |
Issue |
4 |
Pages |
041503,1-3 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000239376500032 |
Publication Date |
2006-08-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0003-6951; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.411 |
Times cited |
32 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.411; 2006 IF: 3.977 |
|
|
Call Number |
UA @ lucian @ c:irua:58732 |
Serial |
2583 |
|
Permanent link to this record |
|
|
|
|
Author |
Vanraes, P.; Parayil Venugopalan, S.; Bogaerts, A. |
|
|
Title |
Multiscale modeling of plasma–surface interaction—General picture and a case study of Si and SiO2etching by fluorocarbon-based plasmas |
Type |
A1 Journal Article |
|
Year |
2021 |
Publication |
Applied Physics Reviews |
Abbreviated Journal |
Appl Phys Rev |
|
|
Volume |
8 |
Issue |
4 |
Pages |
041305 |
|
|
Keywords |
A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; |
|
|
Abstract |
The physics and chemistry of plasma–surface interaction is a broad domain relevant to various applications and several natural processes, including plasma etching for microelectronics fabrication, plasma deposition, surface functionalization, nanomaterial synthesis, fusion reactors, and some astrophysical and meteorological phenomena. Due to their complex nature, each of these processes is generally investigated in separate subdomains, which are considered to have their own theoretical, modeling, and experimental challenges. In this review, however, we want to emphasize the overarching nature of plasma–surface interaction physics and chemistry, by focusing on the general strategy for its computational simulation. In the first half of the review, we provide a menu card with standard and less standardized computational methods to be used for the multiscale modeling of the underlying processes. In the second half, we illustrate the benefits and potential of the multiscale modeling strategy with a case study of Si and SiO2 etching by fluorocarbon plasmas and identify the gaps in knowledge still present on this intensely investigated plasma–material combination, both on a qualitative and quantitative level. Remarkably, the dominant etching mechanisms remain the least understood. The resulting new insights are of general relevance, for all plasmas and materials, including their various applications. We therefore hope to motivate computational and experimental scientists and engineers to collaborate more intensely on filling the existing gaps in knowledge. In this way, we expect that research will overcome a bottleneck stage in the development and optimization of multiscale models, and thus the fundamental understanding of plasma–surface interaction. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000754799700001 |
Publication Date |
2021-10-07 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1931-9401 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
13.667 |
Times cited |
|
Open Access |
OpenAccess |
|
|
Notes |
Asml; P. Vanraes acknowledges funding by ASML for the project “Computational simulation of plasma etching of trench structures.” P. Vanraes wishes to thank Violeta Georgieva and Stefan Tinck for the fruitful discussions on the HPEM code, Yu-Ru Zhang for an example of the CCP reactor code, and Karel Venken for his technical help with the server maintenance and use. P. Vanraes and A. Bogaerts want to express their gratitude to Mark J. Kushner (University of Michigan) for the sharing of the HPEM and MCFPM codes and for the interesting exchange of views. S. P. Venugopalan wishes to thank Sander Wuister, Coen Verschuren, Michael Kubis, Mohammad Kamali, |
Approved |
Most recent IF: 13.667 |
|
|
Call Number |
PLASMANT @ plasmant @c:irua:183287 |
Serial |
6814 |
|
Permanent link to this record |
|
|
|
|
Author |
Van der Paal, J.; Verheyen, C.; Neyts, E.C.; Bogaerts, A. |
|
|
Title |
Hampering Effect of Cholesterol on the Permeation of Reactive Oxygen Species through Phospholipids Bilayer: Possible Explanation for Plasma Cancer Selectivity |
Type |
A1 Journal article |
|
Year |
2017 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
|
|
Volume |
7 |
Issue |
7 |
Pages |
39526 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
In recent years, the ability of cold atmospheric pressure plasmas (CAPS) to selectively induce cell death in cancer cells has been widely established. This selectivity has been assigned to the reactive oxygen and nitrogen species (RONS) created in CAPs. To provide new insights in the search for an explanation
for the observed selectivity, we calculate the transfer free energy of multiple ROS across membranes containing a varying amount of cholesterol. The cholesterol fraction is investigated as a selectivity parameter because membranes of cancer cells are known to contain lower fractions of cholesterol compared to healthy cells. We find that cholesterol has a significant effect on the permeation of
reactive species across a membrane. Indeed, depending on the specific reactive species, an increasing cholesterol fraction can lead to (i) an increase of the transfer free energy barrier height and width, (ii) the formation of a local free energy minimum in the center of the membrane and (iii) the creation of extra free energy barriers due to the bulky sterol rings. In the context of plasma oncology, these observations suggest that the increased ingress of RONS in cancer cells can be explained by the decreased cholesterol fraction of their cell membrane. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000391306900001 |
Publication Date |
2017-01-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.259 |
Times cited |
27 |
Open Access |
OpenAccess |
|
|
Notes |
The authors acknowledge financial support from the Fund for Scientific Research (FWO) Flanders, grant number 11U5416N. The calculations were performed 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: 4.259 |
|
|
Call Number |
PLASMANT @ plasmant @ c:irua:139512 |
Serial |
4340 |
|
Permanent link to this record |
|
|
|
|
Author |
Okhrimovskyy, A.; Bogaerts, A.; Gijbels, R. |
|
|
Title |
Electron anisotropic scattering in gases: a formula for Monte Carlo simulations |
Type |
A1 Journal article |
|
Year |
2002 |
Publication |
Physical review : E : statistical, nonlinear, and soft matter physics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
65 |
Issue |
|
Pages |
037402 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The purpose of this Brief Report is to point out the mistake in a formula for anisotropic electron scattering, previously published in Phys. Rev. A 41, 1112 (1990), which is widely used in Monte Carlo models of gas discharges. Anisotropic electron scattering is investigated based on the screened Coulomb potential between electrons and neutral atoms. The approach is also applied for electron scattering by nonpolar neutral molecules. Differential cross sections for electron scattering by Ar, N2, and CH4 are constructed on the basis of momentum and integrated cross sections. The formula derived in this paper is useful for Monte Carlo simulations of gas discharges. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
Woodbury (NY) |
Editor |
|
|
|
Language |
|
Wos |
000174549000088 |
Publication Date |
2002-07-27 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1063-651X;1095-3787; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
57 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2002 IF: 2.397 |
|
|
Call Number |
UA @ lucian @ c:irua:40179 |
Serial |
909 |
|
Permanent link to this record |
|
|
|
|
Author |
Georgieva, V.; Bogaerts, A. |
|
|
Title |
Negative ion behavior in single- and dual-frequency plasma etching reactors: particle-in-cell/Monte Carlo collision study |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
73 |
Issue |
3 |
Pages |
036402,1-9 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
|
Language |
|
Wos |
000236467700081 |
Publication Date |
2006-06-10 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2006 IF: 2.438 |
|
|
Call Number |
UA @ lucian @ c:irua:57764 |
Serial |
2290 |
|
Permanent link to this record |
|
|
|
|
Author |
Van Gaens, W.; Bogaerts, A. |
|
|
Title |
Reaction pathways of biomedically active species in an Ar plasma jet |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
|
|
Volume |
23 |
Issue |
3 |
Pages |
035015-35027 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
In this paper we analyse the gas phase production and loss pathways for several biomedically active species, i.e. N2(A), O, O3, O2(a), N, H, HO2, OH, NO, NO2, N2O5, H2O2, HNO2 and HNO3, in an argon plasma jet flowing into an open humid air atmosphere. For this purpose, we employ a zero-dimensional reaction kinetics model to mimic the typical experimental conditions by fitting several parameters to experimentally measured values. These include ambient air diffusion, the gas temperature profile and power deposition along the jet effluent. We focus in detail on how the pathways of the biomedically active species change as a function of the position in the effluent, i.e. inside the discharge device, active plasma jet effluent and afterglow region far from the nozzle. Moreover, we demonstrate how the reaction kinetics and species production are affected by different ambient air humidities, total deposited power into the plasma and gas temperature along the jet. It is shown that the dominant pathways can drastically change as a function of the distance from the nozzle exit or experimental conditions. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000337891900017 |
Publication Date |
2014-05-22 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
34 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.302; 2014 IF: 3.591 |
|
|
Call Number |
UA @ lucian @ c:irua:117075 |
Serial |
2820 |
|
Permanent link to this record |
|
|
|
|
Author |
Trenchev, G.; Kolev, S.; Bogaerts, A. |
|
|
Title |
A 3D model of a reverse vortex flow gliding arc reactor |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
|
|
Volume |
25 |
Issue |
25 |
Pages |
035014 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
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. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000376557400022 |
Publication Date |
2016-04-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
20 |
Open Access |
|
|
|
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 |
|
|
Call Number |
c:irua:132888 c:irua:132888 |
Serial |
4063 |
|
Permanent link to this record |
|
|
|
|
Author |
Zhang, Q.-Z.; Bogaerts, A. |
|
|
Title |
Propagation of a plasma streamer in catalyst pores |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
|
|
Volume |
27 |
Issue |
3 |
Pages |
035009 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Although plasma catalysis is gaining increasing interest for various environmental applications, the underlying mechanisms are still far from understood. For instance, it is not yet clear whether and how plasma streamers can propagate in catalyst pores, and what is the minimum pore size to make this happen. As this is crucial information to ensure good plasma-catalyst interaction, we study here the mechanism of plasma streamer propagation in a catalyst pore, by means of a twodimensional particle-in-cell/Monte Carlo collision model, for various pore diameters in the nm range to μm-range. The so-called Debye length is an important criterion for plasma penetration into catalyst pores, i.e. a plasma streamer can penetrate into pores when their diameter is larger than the Debye length. The Debye length is typically in the order of a few 100 nm up to 1 μm at the conditions under study, depending on electron density and temperature in the plasma streamer. For pores in the range of ∼50 nm, plasma can thus only penetrate to some extent and at
very short times, i.e. at the beginning of a micro-discharge, before the actual plasma streamer reaches the catalyst surface and a sheath is formed in front of the surface. We can make plasma streamers penetrate into smaller pores (down to ca. 500 nm at the conditions under study) by increasing the applied voltage, which yields a higher plasma density, and thus reduces the Debye length. Our simulations also reveal that the plasma streamers induce surface charging of the catalyst pore sidewalls, causing discharge enhancement inside the pore, depending on pore diameter and depth. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000427976800001 |
Publication Date |
2018-03-20 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1361-6595 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
16 |
Open Access |
OpenAccess |
|
|
Notes |
We acknowledge financial support from the European Marie Skłodowska-Curie Individual Fellowship within H2020 (Grant Agreement 702604) and from the Fund for Scientific Research Flanders (FWO) (Excellence of Science Program; EOS ID 30505023). This work was carried out in part 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 University of Antwerp. |
Approved |
Most recent IF: 3.302 |
|
|
Call Number |
PLASMANT @ plasmant @c:irua:150877 |
Serial |
4954 |
|
Permanent link to this record |
|
|
|
|
Author |
Saraiva, M.; Georgieva, V.; Mahieu, S.; van Aeken, K.; Bogaerts, A.; Depla, D. |
|
|
Title |
Compositional effects on the growth of Mg(M)O films |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
107 |
Issue |
3 |
Pages |
034902,1-034902,10 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The influence of the composition on the crystallographic properties of deposited Mg(M)O (with M=Al, Cr, Ti, Y, and Zr) films is studied. For a flexible control of the composition, dual reactive magnetron sputtering was used as deposition technique. Two different approaches to predict the composition are discussed. The first is an experimental way based on the simple relationship between the deposition rate and the target-substrate distance. The second is a route using a Monte Carlo based particle trajectory code. Both methods require a minimal experimental input and enable the user to quickly predict the composition of complex thin films. Good control and flexibility allow us to study the compositional effects on the growth of Mg(M)O films. Pure MgO thin films were grown with a (111) preferential out-of-plane orientation. When adding M to MgO, two trends were noticed. The first trend is a change in the MgO lattice parameters compared to pure MgO. The second tendency is a decrease in the crystallinity of the MgO phase. The experimentally determined crystallographic properties are shown to be in correspondence with the predicted properties from molecular dynamics simulations. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000274517300116 |
Publication Date |
2010-02-03 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
|
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.068; 2010 IF: 2.079 |
|
|
Call Number |
UA @ lucian @ c:irua:80346 |
Serial |
447 |
|
Permanent link to this record |
|
|
|
|
Author |
Attri, P.; Yusupov, M.; Park, J.H.; Lingamdinne, L.P.; Koduru, J.R.; Shiratani, M.; Choi, E.H.; Bogaerts, A. |
|
|
Title |
Mechanism and comparison of needle-type non-thermal direct and indirect atmospheric pressure plasma jets on the degradation of dyes |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
Scientific reports |
Abbreviated Journal |
Sci Rep-Uk |
|
|
Volume |
6 |
Issue |
6 |
Pages |
34419 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Purified water supply for human use, agriculture and industry is the major global priority nowadays. The advanced oxidation process based on atmospheric pressure non-thermal plasma (NTP) has been used for purification of wastewater, although the underlying mechanisms of degradation of organic pollutants are still unknown. In this study we employ two needle-type atmospheric pressure non-thermal plasma jets, i.e., indirect (ID-APPJ) and direct (D-APPJ) jets operating at Ar feed gas, for the treatment of methylene blue, methyl orange and congo red dyes, for two different times (i.e., 20 min and 30 min). Specifically, we study the decolorization/degradation of all three dyes using the above mentioned plasma sources, by means of UV-Vis spectroscopy, HPLC and a density meter. We also employ mass spectroscopy to verify whether only decolorization or also degradation takes place after treatment of the dyes by the NTP jets. Additionally, we analyze the interaction of OH radicals with all three dyes using reactive molecular dynamics simulations, based on the density functional-tight binding method. This investigation represents the first report on the degradation of these three different dyes by two types of NTP setups, analyzed by various methods, and based on both experimental and computational studies. |
|
|
Address |
Research Group PLASMANT, Department of Chemistry, University of Antwerp, Universiteitsplein 1, B-2610 Antwerp, Belgium |
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
English |
Wos |
000385172300001 |
Publication Date |
2016-10-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2045-2322 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.259 |
Times cited |
23 |
Open Access |
|
|
|
Notes |
We gratefully acknowledge the grant received from the SRC program of the National Research Foundation of Korea (NRF), funded by the Korean Government (MEST) (No. 20100029418). PA is thankful to FY 2015 Japan Society for the Promotion of Science (JSPS) invitation fellowship. This work was partly supported by MEXT KAKENHI Grant Number 24108009 and JSPS KAKENHI Grant Number JP16H03895. M. Y. gratefully acknowledges financial support from the Research Foundation – Flanders (FWO), grant number 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. |
Approved |
Most recent IF: 4.259 |
|
|
Call Number |
PLASMANT @ plasmant @ c:irua:135847 |
Serial |
4283 |
|
Permanent link to this record |
|
|
|
|
Author |
Paulussen, S.; Verheyde, B.; Tu, X.; De Bie, C.; Martens, T.; Petrovic, D.; Bogaerts, A.; Sels, B. |
|
|
Title |
Conversion of carbon dioxide to value-added chemicals in atmospheric pressure dielectric barrier discharges |
Type |
A1 Journal article |
|
Year |
2010 |
Publication |
Plasma sources science and technology |
Abbreviated Journal |
Plasma Sources Sci T |
|
|
Volume |
19 |
Issue |
3 |
Pages |
034015,1-034015,6 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The aim of this work consists of the evaluation of atmospheric pressure dielectric barrier discharges for the conversion of greenhouse gases into useful compounds. Therefore, pure CO2 feed flows are administered to the discharge zone at varying discharge frequency, power input, gas temperature and feed flow rates, aiming at the formation of CO and O2. The discharge obtained in CO2 is characterized as a filamentary mode with a microdischarge zone in each half cycle of the applied voltage. It is shown that the most important parameter affecting the CO2-conversion levels is the gas flow rate. At low flow rates, both the conversion and the CO-yield are significantly higher. In addition, also an increase in the gas temperature and the power input give rise to higher conversion levels, although the effect on the CO-yield is limited. The optimum discharge frequency depends on the power input level and it cannot be unambiguously stated that higher frequencies give rise to increased conversion levels. A maximum CO2 conversion of 30% is achieved at a flow rate of 0.05 L min−1, a power density of 14.75 W cm−3 and a frequency of 60 kHz. The most energy efficient conversions are achieved at a flow rate of 0.2 L min−1, a power density of 11 W cm−3 and a discharge frequency of 30 kHz. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
Institute of Physics |
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000277982800016 |
Publication Date |
2010-05-22 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0963-0252;1361-6595; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.302 |
Times cited |
116 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.302; 2010 IF: 2.218 |
|
|
Call Number |
UA @ lucian @ c:irua:82408 |
Serial |
512 |
|
Permanent link to this record |
|
|
|
|
Author |
Si, X.-J.; Zhao, S.-X.; Xu, X.; Bogaerts, A.; Wang, Y.-N. |
|
|
Title |
Fluid simulations of frequency effects on nonlinear harmonics in inductively coupled plasma |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
Physics of plasmas |
Abbreviated Journal |
Phys Plasmas |
|
|
Volume |
18 |
Issue |
3 |
Pages |
033504-033504,9 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
A fluid model is self-consistently established to investigate the harmonic effects in an inductively coupled plasma, where the electromagnetic field is solved by the finite difference time domain technique. The spatiotemporal distribution of harmonic current density, harmonic potential, and other plasma quantities, such as radio frequency power deposition, plasma density, and electron temperature, have been investigated. Distinct differences in current density have been observed when calculated with and without Lorentz force, which indicates that the nonlinear Lorentz force plays an important role in the harmonic effects, especially at low frequencies. Moreover, the even harmonics are larger than the odd harmonics both in the current density and the potential. Finally, the dependence of various plasma quantities with and without the Lorentz force on various driving frequencies is also examined. It is shown that the deposited power density decreases and the depth of penetration increases slightly because of the Lorentz force. The electron density increases distinctly while the electron temperature remains almost the same when the Lorentz force is taken into account. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Woodbury, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000289151900073 |
Publication Date |
2011-03-18 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1070-664X; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.115 |
Times cited |
7 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.115; 2011 IF: 2.147 |
|
|
Call Number |
UA @ lucian @ c:irua:87876 |
Serial |
1233 |
|
Permanent link to this record |
|
|
|
|
Author |
Baguer, N.; Bogaerts, A. |
|
|
Title |
Study of the sputtered Cu atoms and Cu+ ions in a hollow cathode glow discharge using a hybrid model |
Type |
A1 Journal article |
|
Year |
2005 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
98 |
Issue |
3 |
Pages |
033303,1-033303,11 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The role of the Cu atoms sputtered from the cathode material in a cylindrical hollow cathode discharge (HCD) and the corresponding Cu+ ions are studied with a self-consistent model based on the principle of Monte Carlo (MC) and fluid simulations. In order to obtain a more realistic view of the discharge processes, this model is coupled with other submodels, which describe the behavior of electrons, fast Ar atoms, Ar+ ions, and Ar metastable atoms, also based on the principles of MC and fluid simulations. Typical results are, among others, the thermalization profile of the Cu atoms, the fast Cu atom, the thermal Cu atom and Cu+ ion fluxes and densities, and the energy distribution of the Cu+ ions. It was found that the contribution of the Ar+ ions to the sputtering was the most significant, followed by the fast Ar atoms. At the cathode bottom, there was no net sputtered flux but a net amount of redeposition. Throughout the discharge volume, at all the conditions investigated, the largest concentration of Cu atoms was found in the lower half of the HCD, close to the bottom. Penning ionization was found the main ionization mechanism for the Cu atoms. The ionization degree of copper atoms was found to be in the same order as for the argon atoms (10-4). (c) 2005 American Institute of Physics. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000231246100007 |
Publication Date |
2005-08-08 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
18 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.068; 2005 IF: 2.498 |
|
|
Call Number |
UA @ lucian @ c:irua:54597 |
Serial |
3340 |
|
Permanent link to this record |
|
|
|
|
Author |
Zhao, S.-X.; Gao, F.; Wang, Y.-P.; Wang, Y.-N.; Bogaerts, A. |
|
|
Title |
Effects of feedstock availability on the negative ion behavior in a C4F8 inductively coupled plasma |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Journal of applied physics |
Abbreviated Journal |
J Appl Phys |
|
|
Volume |
118 |
Issue |
118 |
Pages |
033301 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
In this paper, the negative ion behavior in a C4F8 inductively coupled plasma (ICP) is investigated using a hybrid model. The model predicts a non-monotonic variation of the total negative ion density with power at low pressure (1030 mTorr), and this trend agrees well with experiments that were carried out in many fluorocarbon (fc) ICP sources, like C2F6, CHF3, and C4F8. This behavior is explained by the availability of feedstock C4F8 gas as a source of the negative ions, as well as by the presence of low energy electrons due to vibrational excitation at low power. The maximum of the negative ion density shifts to low power values upon decreasing pressure, because of the more pronounced depletion of C4F8 molecules, and at high pressure (∼50 mTorr), the anion density continuously increases with power, which is similar to fc CCP sources. Furthermore, the negative ion composition is identified in this paper. Our work demonstrates that for a clear understanding of the negative ion behavior in radio frequency C4F8 plasma sources, one needs to take into account many factors, like the attachment characteristics, the anion composition, the spatial profiles, and the reactor configuration. Finally, a detailed comparison of our simulation results with experiments is conducted. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
American Institute of Physics |
Place of Publication |
New York, N.Y. |
Editor |
|
|
|
Language |
|
Wos |
000358429200004 |
Publication Date |
2015-07-20 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0021-8979;1089-7550; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.068 |
Times cited |
1 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.068; 2015 IF: 2.183 |
|
|
Call Number |
c:irua:126735 |
Serial |
861 |
|
Permanent link to this record |
|
|
|
|
Author |
Yusupov, M.; Bultinck, E.; Depla, D.; Bogaerts, A. |
|
|
Title |
Behavior of electrons in a dual-magnetron sputter deposition system : a Monte Carlo model |
Type |
A1 Journal article |
|
Year |
2011 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
|
|
Volume |
13 |
Issue |
|
Pages |
033018-033018,17 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
A Monte Carlo model has been developed for investigating the electron behavior in a dual-magnetron sputter deposition system. To describe the three-dimensional (3D) geometry, different reference frames, i.e. a local and a global coordinate system, were used. In this study, the influence of both closed and mirror magnetic field configurations on the plasma properties is investigated. In the case of a closed magnetic field configuration, the calculated electron trajectories show that if an electron is emitted in (or near) the center of the cathode, where the influence of the magnetic field is low, it is able to travel from one magnetron to the other. On the other hand, when an electron is created at the race track area, it is more or less trapped in the strong magnetic field and cannot easily escape to the second magnetron region. In the case of a mirror magnetic field configuration, irrespective of where the electron is emitted from the cathode, it cannot travel from one magnetron to the other because the magnetic field lines guide the electron to the substrate. Moreover, the electron density and electron impact ionization rate have been calculated and studied in detail for both configurations. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000289064600001 |
Publication Date |
2011-03-15 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.786 |
Times cited |
12 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.786; 2011 IF: 4.177 |
|
|
Call Number |
UA @ lucian @ c:irua:87544 |
Serial |
224 |
|
Permanent link to this record |
|
|
|
|
Author |
Van Gaens, W.; Iseni, S.; Schmidt-Bleker, A.; Weltmann, K.-D.; Reuter, S.; Bogaerts, A. |
|
|
Title |
Numerical analysis of the effect of nitrogen and oxygen admixtures on the chemistry of an argon plasma jet operating at atmospheric pressure |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
New journal of physics |
Abbreviated Journal |
New J Phys |
|
|
Volume |
17 |
Issue |
17 |
Pages |
033003 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
In this paper we study the cold atmospheric pressure plasma jet, called kinpen, operating in Ar with different admixture fractions up to 1% pure , and + . Moreover, the device is operating with a gas curtain of dry air. The absolute net production rates of the biologically active ozone () and nitrogen dioxide () species are measured in the far effluent by quantum cascade laser absorption spectroscopy in the mid-infrared. Additionally, a zero-dimensional semi-empirical reaction kinetics model is used to calculate the net production rates of these reactive molecules, which are compared to the experimental data. The latter model is applied throughout the entire plasma jet, starting already within the device itself. Very good qualitative and even quantitative agreement between the calculated and measured data is demonstrated. The numerical model thus yields very useful information about the chemical pathways of both the and the generation. It is shown that the production of these species can be manipulated by up to one order of magnitude by varying the amount of admixture or the admixture type, since this affects the electron kinetics significantly at these low concentration levels. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Bristol |
Editor |
|
|
|
Language |
|
Wos |
000352898500003 |
Publication Date |
2015-03-03 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1367-2630; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.786 |
Times cited |
29 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.786; 2015 IF: 3.558 |
|
|
Call Number |
c:irua:124228 |
Serial |
2391 |
|
Permanent link to this record |
|
|
|
|
Author |
Andersen, J.A.; Christensen, J.M.; Østberg, M.; Bogaerts, A.; Jensen, A.D. |
|
|
Title |
Plasma-catalytic ammonia decomposition using a packed-bed dielectric barrier discharge reactor |
Type |
A1 Journal article |
|
Year |
2022 |
Publication |
International Journal Of Hydrogen Energy |
Abbreviated Journal |
Int J Hydrogen Energ |
|
|
Volume |
47 |
Issue |
75 |
Pages |
32081-32091 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Plasma-catalytic ammonia decomposition as a method for producing hydrogen was studied in a packed-bed dielectric barrier discharge (DBD) reactor at ambient pressure and a fixed plasma power. The influence of packing the plasma zone with various dielectric materials, typically used as catalyst supports, was examined. At conditions (21 W, 75 Nml/min NH3) where an NH3 conversion of 5% was achieved with plasma alone, an improved decomposition was found when introducing dielectric materials with dielectric constants between 4 and 30. Of the tested materials, MgAl2O4 yielded the highest conversion (15.1%). The particle size (0.3-1.4 mm) of the MgAl2O4 packing was found to have a modest influence on the conversion, which dropped from 15.1% to 12.6% with increasing particle size. Impregnation of MgAl2O4 with different metals was found to decrease the NH3 conversion, with the Ni impregnation still showing an improved conversion (7%) compared to plasma-only. The plasma-assisted ammonia decomposition occurs in the gas phase due to micro-discharges, as evident from a linear correlation between the conversion and the frequency of micro-discharges for both plasma alone and with the various solid packing materials. The primary function of the solid is thus to facilitate the gas phase reaction by assisting the creation of micro-discharges. Lastly, insulation of the reactor to raise the temperature to 230 degrees C in the plasma zone was found to have a negative effect on the conversion, as a change from volume discharges to surface discharges occurred. The study shows that NH3 can be decomposed to provide hydrogen by exposure to a non-thermal plasma, but further developments are needed for it to become an energy efficient technology. (C)2022 The Author(s). Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000865421200012 |
Publication Date |
2022-08-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0360-3199 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
7.2 |
Times cited |
|
Open Access |
OpenAccess |
|
|
Notes |
|
Approved |
Most recent IF: 7.2 |
|
|
Call Number |
UA @ admin @ c:irua:191512 |
Serial |
7191 |
|
Permanent link to this record |
|
|
|
|
Author |
Eckert, M.; Neyts, E.; Bogaerts, A. |
|
|
Title |
On the reaction behaviour of hydrocarbon species at diamond (1 0 0) and (1 1 1) surfaces: a molecular dynamics investigation |
Type |
A1 Journal article |
|
Year |
2008 |
Publication |
Journal of physics: D: applied physics |
Abbreviated Journal |
J Phys D Appl Phys |
|
|
Volume |
41 |
Issue |
|
Pages |
032006,1-3 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
London |
Editor |
|
|
|
Language |
|
Wos |
000253177800006 |
Publication Date |
2008-01-09 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
0022-3727;1361-6463; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.588 |
Times cited |
17 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.588; 2008 IF: 2.104 |
|
|
Call Number |
UA @ lucian @ c:irua:66107 |
Serial |
2449 |
|
Permanent link to this record |
|
|
|
|
Author |
Vanraes, P.; Bogaerts, A. |
|
|
Title |
Plasma physics of liquids—A focused review |
Type |
A1 Journal article |
|
Year |
2018 |
Publication |
Applied physics reviews |
Abbreviated Journal |
Appl Phys Rev |
|
|
Volume |
5 |
Issue |
3 |
Pages |
031103 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The interaction of plasma with liquids has led to various established industrial implementations as well as promising applications, including high-voltage switching, chemical analysis, nanomaterial synthesis, and plasma medicine. Along with these numerous accomplishments, the physics of plasma in liquid or in contact with a liquid surface has emerged as a bipartite research field, for which we introduce here the term “plasma physics of liquids.” Despite the intensive research
investments during the recent decennia, this field is plagued by some controversies and gaps in knowledge, which might restrict further progress. The main difficulties in understanding revolve around the basic mechanisms of plasma initiation in the liquid phase and the electrical interactions at a plasma-liquid interface, which require an interdisciplinary approach. This review aims to provide the wide applied physics community with a general overview of the field, as well as the opportunities for interdisciplinary research on topics, such as nanobubbles and the floating water bridge, and involving the research domains of amorphous semiconductors, solid state physics, thermodynamics, material science, analytical chemistry, electrochemistry, and molecular dynamics simulations. In addition, we provoke awareness of experts in the field on yet underappreciated question marks. Accordingly, a strategy for future experimental and simulation work is proposed. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000446117000003 |
Publication Date |
2018-07-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1931-9401 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
13.667 |
Times cited |
33 |
Open Access |
OpenAccess |
|
|
Notes |
P. Vanraes acknowledges funding by a University of Antwerp BOF grant. The authors express their gratitude to Professor Dr. Peter Bruggeman (University of Minnesota, USA) for very useful comments on a draft of Sec. III C. P. Vanraes is very grateful to Professor Dr. Lars Pettersson (Stockholm University, Sweden) for the interesting discussions on the microscopic structure of water, to Dr. Xiaolong Deng (National University of Defense Technology, China) for his help with the figures, to Dr. Anton Nikiforov (Ghent University, Belgium) for the help with retrieving the relevant chapter of Ref. 319, and to Dr. Tatiana Nikitenko (Vitebst State Masherov University, Belarus), Katja Nygard (Netherlands), Iryna Kuchakova (Ghent University, Belgium), and Mindaugas Kersys (Lithuania) for their tremendous help with the translation of the corresponding chapter. |
Approved |
Most recent IF: 13.667 |
|
|
Call Number |
PLASMANT @ plasmant @c:irua:152823 |
Serial |
5001 |
|
Permanent link to this record |
|
|
|
|
Author |
Tinck, S.; Neyts, E.C.; Bogaerts, A. |
|
|
Title |
Fluorinesilicon surface reactions during cryogenic and near room temperature etching |
Type |
A1 Journal article |
|
Year |
2014 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
|
|
Volume |
118 |
Issue |
51 |
Pages |
30315-30324 |
|
|
Keywords |
A1 Journal article; Engineering sciences. Technology; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Cyrogenic etching of silicon is envisaged to enable better control over plasma processing in the microelectronics industry, albeit little is known about the fundamental differences compared to the room temperature process. We here present molecular dynamics simulations carried out to obtain sticking probabilities, thermal desorption rates, surface diffusion speeds, and sputter yields of F, F2, Si, SiF, SiF2, SiF3, SiF4, and the corresponding ions on Si(100) and on SiF13 surfaces, both at cryogenic and near room temperature. The different surface behavior during conventional etching and cryoetching is discussed. F2 is found to be relatively reactive compared to other species like SiF03. Thermal desorption occurs at a significantly lower rate under cryogenic conditions, which results in an accumulation of physisorbed species. Moreover, ion incorporation is often observed for ions with energies of 30400 eV, which results in a relatively low net sputter yield. The obtained results suggest that the actual etching of Si, under both cryogenic and near room temperature conditions, is based on the complete conversion of the Si surface to physisorbed SiF4, followed by subsequent sputtering of these molecules, instead of direct sputtering of the SiF03 surface. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Washington, D.C. |
Editor |
|
|
|
Language |
|
Wos |
000347360200101 |
Publication Date |
2014-11-25 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1932-7447;1932-7455; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.536 |
Times cited |
11 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 4.536; 2014 IF: 4.772 |
|
|
Call Number |
UA @ lucian @ c:irua:122957 |
Serial |
1239 |
|
Permanent link to this record |
|
|
|
|
Author |
Snoeckx, R.; Zeng, Y.X.; Tu, X.; Bogaerts, A. |
|
|
Title |
Plasma-based dry reforming : improving the conversion and energy efficiency in a dielectric barrier discharge |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
RSC advances |
Abbreviated Journal |
Rsc Adv |
|
|
Volume |
5 |
Issue |
5 |
Pages |
29799-29808 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Dry reforming of methane has gained significant interest over the years. A novel reforming technique with great potential is plasma technology. One of its drawbacks, however, is energy consumption. Therefore, we performed an extensive computational study, supported by experiments, aiming to identify the influence of the operating parameters (gas mixture, power, residence time and frequency) of a dielectric barrier discharge plasma on the conversion and energy efficiency, and to investigate which of these parameters lead to the most promising results and whether these are eventually sufficient for industrial implementation. The best results, in terms of both energy efficiency and conversion, are obtained at a specific energy input (SEI) of 100 J cm−3, a 1090 CH4CO2 ratio, 10 Hz, a residence time of 1 ms, resulting in a total conversion of 84% and an energy efficiency of 8.5%. In general, increasing the CO2 content in the gas mixture leads to a higher conversion and energy efficiency. The SEI couples the effect of the power and residence time, and increasing the SEI always results in a higher conversion, but somewhat lower energy efficiencies. The effect of the frequency is more complicated: we observed that the product of frequency (f) and residence time (τ), being a measure for the total number of micro-discharge filaments which the gas molecules experience when passing through the reactor, was critical. For most cases, a higher number of filaments yields higher values for conversion and energy efficiency. To benchmark our model predictions, we also give an overview of measured conversions and energy efficiencies reported in the literature, to indicate the potential for improvement compared to the state-of-the art. Finally, we identify the limitations as well as the benefits and future possibilities of plasma technology. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000352789500026 |
Publication Date |
2015-03-19 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
2046-2069; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
3.108 |
Times cited |
67 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 3.108; 2015 IF: 3.840 |
|
|
Call Number |
c:irua:132577 |
Serial |
2629 |
|
Permanent link to this record |
|
|
|
|
Author |
Wende, K.; Williams, P.; Dalluge, J.; Van Gaens, W.; Aboubakr, H.; Bischof, J.; von Woedtke, T.; Goyal, S.M.; Weltmann, K.D.; Bogaerts, A.; Masur, K.; Bruggeman, P.J.; |
|
|
Title |
Identification of the biologically active liquid chemistry induced by a nonthermal atmospheric pressure plasma jet |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Biointerphases |
Abbreviated Journal |
Biointerphases |
|
|
Volume |
10 |
Issue |
10 |
Pages |
029518 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The mechanism of interaction of cold nonequilibrium plasma jets with mammalian cells in physiologic liquid is reported. The major biological active species produced by an argon RF plasma jet responsible for cell viability reduction are analyzed by experimental results obtained through physical, biological, and chemical diagnostics. This is complemented with chemical kinetics modeling of the plasma source to assess the dominant reactive gas phase species. Different plasma chemistries are obtained by changing the feed gas composition of the cold argon based RF plasma jet from argon, humidified argon (0.27%), to argon/oxygen (1%) and argon/air (1%) at constant power. A minimal consensus physiologic liquid was used, providing isotonic and isohydric conditions and nutrients but is devoid of scavengers or serum constituents. While argon and humidified argon plasma led to the creation of hydrogen peroxide dominated action on the mammalian cells, argonoxygen and argonair plasma created a very different biological action and was characterized by trace amounts of hydrogen peroxide only. In particular, for the argonoxygen (1%), the authors observed a strong negative effect on mammalian cell proliferation and metabolism. This effect was distance dependent and showed a half life time of 30 min in a scavenger free physiologic buffer. Neither catalase and mannitol nor superoxide dismutase could rescue the cell proliferation rate. The strong distance dependency of the effect as well as the low water solubility rules out a major role for ozone and singlet oxygen but suggests a dominant role of atomic oxygen. Experimental results suggest that O reacts with chloride, yielding Cl2 − or ClO−. These chlorine species have a limited lifetime under physiologic conditions and therefore show a strong time dependent biological activity. The outcomes are compared with an argon MHz plasma jet (kinpen) to assess the differences between these (at least seemingly) similar plasma sources. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000357195600036 |
Publication Date |
2015-05-06 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1934-8630;1559-4106; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.603 |
Times cited |
137 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.603; 2015 IF: 3.374 |
|
|
Call Number |
c:irua:126774 |
Serial |
1549 |
|
Permanent link to this record |
|
|
|
|
Author |
Khosravian, N.; Bogaerts, A.; Huygh, S.; Yusupov, M.; Neyts, E.C. |
|
|
Title |
How do plasma-generated OH radicals react with biofilm components? Insights from atomic scale simulations |
Type |
A1 Journal article |
|
Year |
2015 |
Publication |
Biointerphases |
Abbreviated Journal |
Biointerphases |
|
|
Volume |
10 |
Issue |
10 |
Pages |
029501 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The application of nonthermal atmospheric pressure plasma is emerging as an alternative and efficient technique for the inactivation of bacterial biofilms. In this study, reactive molecular dynamics simulations were used to examine the reaction mechanisms of hydroxyl radicals, as key reactive oxygen plasma species in biological systems, with several organic molecules (i.e., alkane, alcohol, carboxylic acid, and amine), as prototypical components of biomolecules in the biofilm. Our results demonstrate that organic molecules containing hydroxyl and carboxyl groups may act as trapping agents for the OH radicals. Moreover, the impact of OH radicals on N-acetyl-glucosamine, as constituent component of staphylococcus epidermidis biofilms, was investigated. The results show how impacts of OH radicals lead to hydrogen abstraction and subsequent molecular damage. This study thus provides new data on the reaction mechanisms of plasma species, and particularly the OH radicals, with fundamental components of bacterial biofilms. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000357195600019 |
Publication Date |
2014-12-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1934-8630;1559-4106; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.603 |
Times cited |
10 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.603; 2015 IF: 3.374 |
|
|
Call Number |
c:irua:121371 |
Serial |
1492 |
|
Permanent link to this record |
|
|
|
|
Author |
Georgieva, V.; Bogaerts, A.; Gijbels, R. |
|
|
Title |
Numerical investigation of ion energy distribution functions in single and dual frequency capacitively coupled plasma reactors |
Type |
A1 Journal article |
|
Year |
2004 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
69 |
Issue |
|
Pages |
026406 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
|
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
|
Language |
|
Wos |
000220255500058 |
Publication Date |
2004-02-24 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
97 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2004 IF: NA |
|
|
Call Number |
UA @ lucian @ c:irua:44025 |
Serial |
2395 |
|
Permanent link to this record |
|
|
|
|
Author |
de Bleecker, K.; Bogaerts, A.; Goedheer, W. |
|
|
Title |
Detailed modeling of hydrocarbon nanoparticle nucleation in acetylene discharges |
Type |
A1 Journal article |
|
Year |
2006 |
Publication |
Physical review : E : statistical physics, plasmas, fluids, and related interdisciplinary topics |
Abbreviated Journal |
Phys Rev E |
|
|
Volume |
73 |
Issue |
2 |
Pages |
026405,1-16 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
The initial stage of nanoparticle formation and growth in radiofrequency acetylene (C2H2) plasmas is investigated by means of a self-consistent one-dimensional fluid model. A detailed chemical kinetic scheme, containing electron impact, ion-neutral, and neutral-neutral reactions, has been developed in order to predict the underlying dust growth mechanisms and the most important dust precursors. The model considers 41 different species (neutrals, radicals, ions, and electrons) describing hydrocarbons (CnHm) containing up to 12 carbon atoms. Possible routes for particle growth are discussed. Both positive and negative ion reaction pathways are considered, as consecutive anion- and cation-molecule reactions seem to lead to a fast build up of the carbon skeleton. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
Lancaster, Pa |
Editor |
|
|
|
Language |
|
Wos |
000235667700086 |
Publication Date |
2006-03-10 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1539-3755;1550-2376; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
2.366 |
Times cited |
89 |
Open Access |
|
|
|
Notes |
|
Approved |
Most recent IF: 2.366; 2006 IF: 2.438 |
|
|
Call Number |
UA @ lucian @ c:irua:56337 |
Serial |
666 |
|
Permanent link to this record |
|
|
|
|
Author |
Zhang, Y.-R.; Neyts, E.C.; Bogaerts, A. |
|
|
Title |
Influence of the Material Dielectric Constant on Plasma Generation inside Catalyst Pores |
Type |
A1 Journal article |
|
Year |
2016 |
Publication |
The journal of physical chemistry: C : nanomaterials and interfaces |
Abbreviated Journal |
J Phys Chem C |
|
|
Volume |
120 |
Issue |
120 |
Pages |
25923-25934 |
|
|
Keywords |
A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
|
|
Abstract |
Plasma catalysis is gaining increasing interest for various environmental applications, but the crucial question is whether plasma can be created inside catalyst pores and under which conditions. In practice, various catalytic support materials are used, with various dielectric constants. We investigate here the influence of the dielectric constant on the plasma properties inside catalyst pores and in the sheath in front of the pores, for various pore sizes. The calculations are performed by a two-dimensional fluid model for an atmospheric pressure dielectric barrier discharge in helium. The electron impact ionization rate, electron temperature, electron and ion density, as well as the potential distribution and surface charge density, are analyzed for a better understanding of the discharge behavior inside catalyst pores. The results indicate that, in a 100 μm pore, the electron impact ionization in the pore, which is characteristic for the plasma generation inside the pore, is greatly enhanced for dielectric constants below 300. Smaller pore sizes only yield enhanced ionization for smaller dielectric constants, i.e., up to εr = 200, 150, and 50 for pore sizes of 50, 30, and 10 μm. Thus, the most common catalyst supports, i.e., Al2O3 and SiO2, which have dielectric constants around εr = 8−11 and 4.2, respectively, should allow more easily that microdischarges can be formed inside catalyst pores, even for smaller pore sizes. On the other hand, ferroelectric materials with dielectric constants above 300 never seem to yield plasma enhancement inside catalyst pores, not even for 100 μm pore sizes. Furthermore, it is clear that the dielectric constant of the material has a large effect on the extent of plasma enhancement inside the catalyst pores, especially in the range between εr = 4 and εr = 200. The obtained results are explained in detail based on the surface charge density at the pore walls,
and the potential distribution and electron temperature inside and above the pores. The results obtained with this model are
important for plasma catalysis, as the production plasma species in catalyst pores might affect the catalyst properties, and thus
improve the applications of plasma catalysis. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000388429100029 |
Publication Date |
2016-11-17 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1932-7447 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.536 |
Times cited |
34 |
Open Access |
|
|
|
Notes |
This work was supported by the Fund for Scientific Research Flanders (FWO) (Grant G.0217.14N), the National Natural Science Foundation of China (Grant 11405019), and the China Postdoctoral Science Foundation (Grant 2015T80244). This work was carried out in part 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 University of Antwerp. |
Approved |
Most recent IF: 4.536 |
|
|
Call Number |
PLASMANT @ plasmant @ c:irua:138602 |
Serial |
4319 |
|
Permanent link to this record |
|
|
|
|
Author |
Vermeiren, V.; Bogaerts, A. |
|
|
Title |
Supersonic Microwave Plasma: Potential and Limitations for Energy-Efficient CO2Conversion |
Type |
A1 Journal Article |
|
Year |
2018 |
Publication |
Journal Of Physical Chemistry C |
Abbreviated Journal |
J Phys Chem C |
|
|
Volume |
122 |
Issue |
45 |
Pages |
25869-25881 |
|
|
Keywords |
A1 Journal Article; Plasma, laser ablation and surface modeling Antwerp (PLASMANT) ; |
|
|
Abstract |
Supersonic flows provide a high thermodynamic
nonequilibrium, which is crucial for energy-efficient conversion of
CO 2 in microwave plasmas and are therefore of great interest.
However, the effect of the flow on the chemical reactions is poorly
understood. In this work, we present a combined flow and plasma
chemical kinetics model of a microwave CO 2 plasma in a Laval
nozzle setup. The effects of the flow field on the different dissociation
and recombination mechanisms, the vibrational distribution, and the
vibrational transfer mechanism are discussed. In addition, the effect
of experimental parameters, like position of power deposition, outlet
pressure, and specific energy input, on the CO 2 conversion and
energy efficiency is examined. The short residence time of the gas in
the plasma region, the shockwave, and the maximum critical heat,
and thus power, that can be added to the flow to avoid thermal
choking are the main obstacles to reaching high energy efficiencies. |
|
|
Address |
|
|
|
Corporate Author |
|
Thesis |
|
|
|
Publisher |
|
Place of Publication |
|
Editor |
|
|
|
Language |
|
Wos |
000451101400016 |
Publication Date |
2018-11-15 |
|
|
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
|
Series Volume |
|
Series Issue |
|
Edition |
|
|
|
ISSN |
1932-7447 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
|
|
Impact Factor |
4.536 |
Times cited |
5 |
Open Access |
Not_Open_Access |
|
|
Notes |
Fonds Wetenschappelijk Onderzoek, G.0383.16N ; |
Approved |
Most recent IF: 4.536 |
|
|
Call Number |
PLASMANT @ plasmant @c:irua:155412 |
Serial |
5070 |
|
Permanent link to this record |