“Single-step alcohol-free synthesis of coreshell nanoparticles of \gamma-casein micelles and silica”. Kerkhofs S, Leroux F, Allouche L, Mellaerts R, Jammaer J, Aerts A, Kirschhock CEA, Magusin PCMM, Taulelle F, Bals S, Van Tendeloo G, Martens JA;, RSC advances 4, 25650 (2014). http://doi.org/10.1039/C4RA03252G
Abstract: A new, single-step protocol for wrapping individual nanosized β-casein micelles with silica is presented. This biomolecule-friendly synthesis proceeds at low protein concentration at almost neutral pH, and makes use of sodium silicate instead of the common silicon alkoxides. This way, formation of potentially protein-denaturizing alcohols can be avoided. The pH of the citrate-buffered synthesis medium is close to the isoelectric point of β-casein, which favours micelle formation. A limited amount of sodium silicate is added to the protein micelle suspension, to form a thin silica coating around the β-casein micelles. The size distribution of the resulting proteinsilica structures was characterized using DLS and SAXS, as well as 1H NMR DOSY with a dedicated pulsed-field gradient cryo-probehead to cope with the low protein concentration. The degree of silica-condensation was investigated by 29Si MAS NMR, and the nanostructure was revealed by advanced electron microscopy techniques such as ESEM and HAADF-STEM. As indicated by the combined characterization results, a silica shell of 2 nm is formed around individual β-casein micelles giving rise to separate protein coresilica shell nanoparticles of 17 nm diameter. This alcohol-free method at mild temperature and pH is potentially suited for packing protein molecules into bio-compatible silica nanocapsules for a variety of applications in biosensing, therapeutic protein delivery and biocatalysis.
Keywords: A1 Journal article; Electron microscopy for materials research (EMAT)
Impact Factor: 3.108
Times cited: 3
DOI: 10.1039/C4RA03252G
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“Plasma-based dry reforming : improving the conversion and energy efficiency in a dielectric barrier discharge”. Snoeckx R, Zeng YX, Tu X, Bogaerts A, RSC advances 5, 29799 (2015). http://doi.org/10.1039/C5RA01100K
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.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.108
Times cited: 67
DOI: 10.1039/C5RA01100K
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“Transport of cystine across xC-antiporter”. Ghasemitarei M, Yusupov M, Razzokov J, Shokri B, Bogaerts A, Archives of biochemistry and biophysics 664, 117 (2019). http://doi.org/10.1016/j.abb.2019.01.039
Abstract: Extracellular cystine (CYC) uptake by xC antiporter is important for the cell viability. Especially in cancer cells, the upregulation of xC activity is observed, which protects these cells from intracellular oxidative stress. Hence, inhibition of the CYC uptake may eventually lead to cancer cell death. Up to now, the molecular level mechanism of the CYC uptake by xC antiporter has not been studied in detail. In this study, we applied several different simulation techniques to investigate the transport of CYC through xCT, the light subunit of the xC antiporter, which is responsible for the CYC and glutamate translocation. Specifically, we studied the permeation of CYC across three model systems, i.e., outward facing (OF), occluded (OCC) and inward facing (IF) configurations of xCT. We also investigated the effect of mutation of Cys327 to Ala within xCT, which was also studied experimentally in literature. This allowed us to qualitatively compare our computation results with experimental observations, and thus, to validate our simulations. In summary, our simulations provide a molecular level mechanism of the transport of CYC across the xC antiporter, more specifically, which amino acid residues in the xC antiporter play a key role in the uptake, transport and release of CYC.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.165
Times cited: 3
DOI: 10.1016/j.abb.2019.01.039
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“Effect of oxidative stress on cystine transportation by xC&oline, antiporter”. Ghasemitarei M, Yusupov M, Razzokov J, Shokri B, Bogaerts A, Archives of biochemistry and biophysics 674, 108114 (2019). http://doi.org/10.1016/j.abb.2019.108114
Abstract: We performed computer simulations to investigate the effect of oxidation on the extracellular cystine (CYC) uptake by the xC− antiporter. The latter is important for killing of cancer cells. Specifically, applying molecular dynamics (MD) simulations we studied the transport of CYC across xCT, i.e., the light subunit of the xC− antiporter, in charge of bidirectional transport of CYC and glutamate. We considered the outward facing (OF) configuration of xCT, and to study the effect of oxidation, we modified the Cys327 residue, located in the vicinity of the extracellular milieu, to cysteic acid (CYO327). Our computational results showed that oxidation of Cys327 results in a free energy barrier for CYC translocation, thereby blocking the access of CYC to the substrate binding site of the OF system. The formation of the energy barrier was found to be due to the conformational changes in the channel. Analysis of the MD trajectories revealed that the reorganization of the side chains of the Tyr244 and CYO327 residues play a critical role in the OF channel blocking. Indeed, the calculated distance between Tyr244 and either Cys327 or CYO327 showed a narrowing of the channel after oxidation. The obtained free energy barrier for CYC translocation was found to be 33.9kJmol−1, indicating that oxidation of Cys327, by e.g., cold atmospheric plasma, is more effective in inhibiting the xC− antiporter than in the mutation of this amino acid to Ala (yielding a barrier of 32.4kJmol−1). The inhibition of the xC− antiporter may lead to Cys starvation in some cancer cells, eventually resulting in cancer cell death.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.165
DOI: 10.1016/j.abb.2019.108114
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“Risk Evaluation of EMT and Inflammation in Metastatic Pancreatic Cancer Cells Following Plasma Treatment”. Freund E, Spadola C, Schmidt A, Privat-Maldonado A, Bogaerts A, von Woedtke T, Weltmann K-D, Heidecke C-D, Partecke L-I, Käding A, Bekeschus S, Frontiers in physics 8 (2020). http://doi.org/10.3389/fphy.2020.569618
Abstract: The requirements for new technologies to serve as anticancer agents go far beyond their toxicity potential. Novel applications also need to be safe on a molecular and patient level. In a broader sense, this also relates to cancer metastasis and inflammation. In a previous study, the toxicity of an atmospheric pressure argon plasma jet in four human pancreatic cancer cell lines was confirmed and plasma treatment did not promote metastasis in vitro and in ovo. Here, these results are extended by additional types of analysis and new models to validate and define on a molecular level the changes related to metastatic processes in pancreatic cancer cells following plasma treatment in vitro and in ovo. In solid tumors that were grown on the chorion-allantois membrane of fertilized chicken eggs (TUM-CAM), plasma treatment induced modest to profound apoptosis in the tissues. This, however, was not associated with a change in the expression levels of adhesion molecules, as shown using immunofluorescence of ultrathin tissue sections. Culturing of the cells detached from these solid tumors for 6d revealed a similar or smaller total growth area and expression of ZEB1, a transcription factor associated with cancer metastasis, in the plasma-treated pancreatic cancer tissues. Analysis of in vitro and in ovo supernatants of 13 different cytokines and chemokines revealed cell line-specific effects of the plasma treatment but a noticeable increase of, e.g., growth-promoting interleukin 10 was not observed. Moreover, markers of epithelial-to-mesenchymal transition (EMT), a metastasis-promoting cellular program, were investigated. Plasma-treated pancreatic cancer cells did not present an EMT-profile. Finally, a realistic 3D tumor spheroid co-culture model with pancreatic stellate cells was employed, and the invasive properties in a gel-like cellular matrix were investigated. Tumor outgrowth and spread was similar or decreased in the plasma conditions. Altogether, these results provide valuable insights into the effect of plasma treatment on metastasis-related properties of cancer cells and did not suggest EMT-promoting effects of this novel cancer therapy.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.1
DOI: 10.3389/fphy.2020.569618
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“The Quest to Quantify Selective and Synergistic Effects of Plasma for Cancer Treatment: Insights from Mathematical Modeling”. Bengtson C, Bogaerts A, International Journal Of Molecular Sciences 22, 5033 (2021). http://doi.org/10.3390/ijms22095033
Abstract: Cold atmospheric plasma (CAP) and plasma-treated liquids (PTLs) have recently become a promising option for cancer treatment, but the underlying mechanisms of the anti-cancer effect are still to a large extent unknown. Although hydrogen peroxide () has been recognized as the major anti-cancer agent of PTL and may enable selectivity in a certain concentration regime, the co-existence of nitrite can create a synergistic effect. We develop a mathematical model to describe the key species and features of the cellular response toward PTL. From the numerical solutions, we define a number of dependent variables, which represent feasible measures to quantify cell susceptibility in terms of the membrane diffusion rate constant and the intracellular catalase concentration. For each of these dependent variables, we investigate the regimes of selective versus non-selective, and of synergistic versus non-synergistic effect to evaluate their potential role as a measure of cell susceptibility. Our results suggest that the maximal intracellular concentration, which in the selective regime is almost four times greater for the most susceptible cells compared to the most resistant cells, could be used to quantify the cell susceptibility toward exogenous . We believe our theoretical approach brings novelty to the field of plasma oncology, and more broadly, to the field of redox biology, by proposing new ways to quantify the selective and synergistic anti-cancer effect of PTL in terms of inherent cell features.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.226
DOI: 10.3390/ijms22095033
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“Laser-induced excitation mechanisms and phase transitions in spectrochemical analysis &ndash, Review of the fundamentals”. Vanraes P, Bogaerts A, Spectrochimica Acta Part B-Atomic Spectroscopy 179, 106091 (2021). http://doi.org/10.1016/j.sab.2021.106091
Abstract: Nowadays, lasers are commonly applied in spectrochemical analysis methods, for sampling, plasma formation or a combination of both. Despite the numerous investigations that have been performed on these applications, the underlying processes are still insufficiently understood. In order to fasten progress in the field and in honor of the lifework of professor Rick Russo, we here provide a brief overview of the fundamental mechanisms in lasermatter interaction as proposed in literature, and throw the spotlight on some aspects that have not received much attention yet. For an organized discussion, we choose laser ablation, laser desorption and the associated gaseous plasma formation as the central processes in this perspective article, based on a classification of the laserbased spectrochemical analysis techniques and the corresponding laser-matter interaction regimes. First, we put the looking glass over the excitation and thermalization mechanisms in the laser-irradiated condensed phase, for which we propose the so-called multi-plasma model. This novel model can be understood as an extension of the well-known two-temperature model, featuring multiple thermodynamic dimensions, each of which corresponds to a quasi-particle type. Next, the focus is placed on the mass transfer and ionization mechanisms, after which we shortly highlight the possible role of anisotropic and magnetic effects in the laser-excited material. We hope this perspective article motivates more fundamental research on laser-matter interaction, as a continuation of the lifework of Rick Russo.
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
DOI: 10.1016/j.sab.2021.106091
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“Calculation of crater profiles on a flat cathode in a direct current glow discharge, and comparison with experiment”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 52, 765 (1997)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 42
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“Comparison of argon and neon as discharge gases in a direct current glow discharge: a mathematical simulation”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 52, 553 (1997)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 13
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“Three-dimensional density profiles of sputtered atoms and ions in a direct current glow discharge: experimental study and comparison with calculations”. Bogaerts A, Wagner E, Smith BW, Winefordner JD, Pollmann D, Harrison WW, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 52, 205 (1997)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 46
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“Three-dimensional density profiles of the argon metastable atoms in a direct current glow discharge: experimental study and comparison with calculations”. Bogaerts A, Guenard RD, Smith BW, Winefordner JD, Harrison WW, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 52, 219 (1997)
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 36
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“Collisional-radiative model for the sputtered copper atoms and ions in a direct current argon glow discharge”. Bogaerts A, Gijbels R, Carman RJ, Spectrochimica acta: part B : atomic spectroscopy 53, 1679 (1998). http://doi.org/10.1016/S0584-8547(98)00201-8
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 71
DOI: 10.1016/S0584-8547(98)00201-8
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“Comprehensive description of a Grimm-type glow discharge source used for optical emission spectrometry: a mathematical simulation”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 53, 437 (1998). http://doi.org/10.1016/S0584-8547(97)00148-1
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 46
DOI: 10.1016/S0584-8547(97)00148-1
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“Fundamental aspects and applications of glow discharge spectrometric techniques”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 53, 1 (1998). http://doi.org/10.1016/S0584-8547(97)00122-5
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 49
DOI: 10.1016/S0584-8547(97)00122-5
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“Modeling of glow discharge optical emission spectrometry: calculation of the argon atomic optical emission spectrum”. Bogaerts A, Gijbels R, Vlcek J, Spectrochimica acta: part B : atomic spectroscopy 53, 1517 (1998). http://doi.org/10.1016/S0584-8547(98)00139-6
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 44
DOI: 10.1016/S0584-8547(98)00139-6
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“Comparison between a radio-frequency and direct current glow discharge in argon by a hybrid Monte Carlo-fluid model for electrons, argon ions and fast argon atoms”. Bogaerts A, Gijbels R, Goedheer W, Spectrochimica acta: part B : atomic spectroscopy 54, 1335 (1999). http://doi.org/10.1016/S0584-8547(99)00080-4
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 11
DOI: 10.1016/S0584-8547(99)00080-4
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“Behavior of the sputtered copper atoms, ions and excited species in a radio-frequency and direct current glow discharge”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 55, 279 (2000). http://doi.org/10.1016/S0584-8547(00)00142-7
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 17
DOI: 10.1016/S0584-8547(00)00142-7
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“Comparison of calculated and measured optical emission intensities in a direct current argon-copper glow discharge”. Bogaerts A, Donko Z, Kutasi K, Bano G, Pinhao N, Pinheiro M, Spectrochimica acta: part B : atomic spectroscopy 55, 1465 (2000). http://doi.org/10.1016/S0584-8547(00)00253-6
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 33
DOI: 10.1016/S0584-8547(00)00253-6
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“Description of the argon-excited levels in a radio-frequency and direct current glow discharge”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 55, 263 (2000). http://doi.org/10.1016/S0584-8547(00)00143-9
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 24
DOI: 10.1016/S0584-8547(00)00143-9
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“Comparison of modeling calculations with experimental results for direct current glow discharge optical emission spectrometry”. Bogaerts A, Wilken L, Hoffmann V, Gijbels R, Wetzig K, Spectrochimica acta: part B : atomic spectroscopy 56, 551 (2001). http://doi.org/10.1016/S0584-8547(01)00220-8
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 16
DOI: 10.1016/S0584-8547(01)00220-8
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“Comparison of modeling calculations with experimental results for rf glow discharge optical emission spectrometry”. Bogaerts A, Wilken L, Hoffmann V, Gijbels R, Wetzig K, Spectrochimica acta: part B : atomic spectroscopy 57, 109 (2002). http://doi.org/10.1016/S0584-8547(01)00357-3
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 14
DOI: 10.1016/S0584-8547(01)00357-3
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“Gas discharge plasmas and their applications”. Bogaerts A, Neyts E, Gijbels R, van der Mullen J, Spectrochimica acta: part B : atomic spectroscopy 57, 609 (2002). http://doi.org/10.1016/S0584-8547(01)00406-2
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 462
DOI: 10.1016/S0584-8547(01)00406-2
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“Hybrid model for a cylindrical hollow cathode glow discharge and comparison with experiments”. Baguer N, Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 57, 311 (2002). http://doi.org/10.1016/S0584-8547(01)00385-8
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 31
DOI: 10.1016/S0584-8547(01)00385-8
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“Hybrid Monte-Carlo-fluid modeling network for an argon/hydrogen direct current glow discharge”. Bogaerts A, Gijbels R, Spectrochimica acta: part B : atomic spectroscopy 57, 1071 (2002). http://doi.org/10.1016/S0584-8547(02)00047-2
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 68
DOI: 10.1016/S0584-8547(02)00047-2
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“Laser ablation for analytical sampling: what can we learn from modeling?”.Bogaerts A, Chen Z, Gijbels R, Vertes A, Spectrochimica acta: part B : atomic spectroscopy 58, 1867 (2003). http://doi.org/10.1016/j.sab.2003.08.004
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 321
DOI: 10.1016/j.sab.2003.08.004
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“Change in silica sources in Roman and post Roman glass”. Aerts A, Janssens K, Velde B, Dijkman W, Spectrochimica acta: part B : atomic spectroscopy 58, 659 (2003). http://doi.org/10.1016/S0584-8547(02)00287-2
Keywords: A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Impact Factor: 3.241
DOI: 10.1016/S0584-8547(02)00287-2
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“Computer simulations of crater profiles in glow discharge optical emission spectrometry: comparison with experiments and investigation of the underlying mechanisms”. Bogaerts A, Verscharen W, Steers E, Spectrochimica acta: part B : atomic spectroscopy 59, 1403 (2004). http://doi.org/10.1016/j.sab.2004.06.005
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 14
DOI: 10.1016/j.sab.2004.06.005
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“Fundamental studies on a planar-cathode direct current glow discharge: part 1: characterization via laser scattering techniques”. Gamez G, Bogaerts A, Andrade F, Hieftje GM, Spectrochimica acta: part B : atomic spectroscopy 59, 435 (2004). http://doi.org/10.1016/j.sab.2003.12.002
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 24
DOI: 10.1016/j.sab.2003.12.002
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“Fundamental studies on a planar-cathode direct current glow discharge: part 2: numerical modeling and comparison with laser scattering experiments”. Bogaerts A, Gijbels R, Gamez G, Hieftje GM, Spectrochimica acta: part B : atomic spectroscopy 59, 449 (2004). http://doi.org/10.1016/j.sab.2003.12.001
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 26
DOI: 10.1016/j.sab.2003.12.001
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“Effect of laser parameters on laser ablation and laser-induced plasma formation: a numerical modeling investigation”. Bogaerts A, Chen Z, Spectrochimica acta: part B : atomic spectroscopy 60, 1280 (2005). http://doi.org/10.1016/j.sab.2005.06.009
Keywords: A1 Journal article; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Impact Factor: 3.241
Times cited: 165
DOI: 10.1016/j.sab.2005.06.009
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