Dielectric Barrier Discharge

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Pulsed Current-Mode Supply of Dielectric Barrier Discharge Excilamps for the Control of the Radiated Ultraviolet Power

Pulsed Current-Mode Supply of Dielectric Barrier Discharge Excilamps for the Control of the Radiated Ultraviolet Power

M. V. Erofeev is with the Institute of High Current Electronics, Siberian Branch of Russian Academy of Sciences, Tomsk 634055, Russia (e-mail: michael@loi.hcei.tsc.ru). cal, photochemical, and photophysical processes, such as the inactivation of microorganisms [1], [2], photolytic processing of metal, dielectric and semiconductor layers, surface cleaning and decomposition of harmful organics [3]–[5]. The absence of mercury in working mixture is another advantage of excilamps which is very important from the ecological point of view. The most promising excilamps are those excited by dielectric barrier discharge (DBD) [6]–[8]. DBD are electric discharges between two metallic electrodes, with at least one of them covered by a dielectric material. Excilamps with two barriers have longer lifetimes due to the absence of direct contact between the working gas mixture and the metallic electrodes.
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CO2 reforming of methane: valorizing CO2 by means of Dielectric Barrier Discharge

CO2 reforming of methane: valorizing CO2 by means of Dielectric Barrier Discharge

instead of a product that can be stocked. The case considered in this work is the CO 2 reformation of methane producing hydrogen and CO. It is an endothermic reaction, for which the activition barrier needs to be overcome. The method of Dielectric Barrier Discharge can do this efficiently. The process relies on the collision of electrons, which are accelerated under an electrical field that is created in the discharge area. This leads to the formation of reactive species, which facilitate the abovementioned reaction. The determination of the electron density is performed by PLASIMO. The study is subsequently continued using the Reaction Engineering module in COMSOL (with an incorporated kinetic mechanism) in order to model the discharge phase. Then COMSOL (continuity and Navier-Stokes equations) is used to model the flow in the post-discharge phase. The results showed that both a 2D and 3D model can be used to model the chemical-plasma process. These methods need strongly reduced kinetic mechanism, which in some cases can cause loss of precision. It is also observed that the present experimental set-up that is modeled needs to be improved. A suggestion is made.
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Development, Physics, Technology and Operation of a "Pilot-Scale" Dielectric Barrier Discharge Reactor

Development, Physics, Technology and Operation of a "Pilot-Scale" Dielectric Barrier Discharge Reactor

Energetics of Noble Gas Dielectric Barrier Discharges (DBD): Novel Results Related to Electrode Areas and Dielectric Materials Abstract— Two dielectric barrier discharge (DBD) reactors, one small, the other about 40 times larger, associated equipment and a dedicated Matlab ® code have been used to carry out precise determinations of electrical energy, , dissipated per discharge cycle of the applied a.c. voltage, . In the smaller reactor, this was done over the frequency range 5 ≤ ≤ 50 kHz and using twin pairs of several different insulating materials (2.54 cm diameter discs) with relative permittivities between 2.1 ≤ ≤ 9.5 as dielectric barriers in DBDs for 4 different gases: He, Ne, Ar and N 2 . In the large reactor, f was restricted to 20 kHz in Ar and He; this latter system primarily serves for plasma polymerization experiments in which organic “monomers” are admixed with the flow of Ar as carrier gas. We report the method for exactly evaluating , then present and compare values measured under different conditions. To the extent possible, these are compared between the small and large reactors, and with results published in the literature. The reliability of the method is confirmed, for example, by reproducing published breakdown fields of the gases examined, and by several other original results.
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Parametric study of dielectric barrier discharge excimer UV lamps supplied with controlled square current pulses

Parametric study of dielectric barrier discharge excimer UV lamps supplied with controlled square current pulses

Keywords: dielectric barrier discharge, excimer lamps, UV emission, power supply, current source. 1. INTRODUCTION UV lamps of Dielectric Barrier Discharge (DBD) structure are environmentally friendly (mercury free) UV sources used for various applications: health, disinfection, surface treatments [1]. The applicability of these DBD excilamps has been demonstrated; today, studies are oriented toward the improvement of their performance. This can be achieved by means of the bulb design (geometry, filling mixture, pressure and materials) [2], [3] and also by selecting the most performing electrical operating conditions [4],[5].These both optimization paths are the purpose of this paper: the characteristics of the candidate bulbs, which performances will be experimentally compared, are presented in §2 and an estimation of the parameters of their equivalent circuit model is displayed. Associated to this set of lamps, the selected power supply, by means of a square shape current source generator is presented in §3: the operating principles of this topology, together with its performances are presented; elements for the design of the actual generator, specifically developed for this study are also proposed. Each bulb under test is connected to this power supply and the operation of the whole system is controlled and monitored by means of a test bench which is described in §0. The measurements achieved on the bench are used for several purposes: firstly, to measure the characteristics of each bulb (§5). Secondly, (§0), the performances obtained with each bulb, under similar supplying conditions, are compared in order to select the lamp and its operating conditions which offer the best results. Comparisons are focused on the efficiencies of: the conversion from electrical power to UV emission, the power supply (input and output powers ratio) and the whole system (energetic efficiency).
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Pulsed Current-Mode Supply of Dielectric Barrier Discharge Excilamps for the Control of the Radiated Ultraviolet Power

Pulsed Current-Mode Supply of Dielectric Barrier Discharge Excilamps for the Control of the Radiated Ultraviolet Power

M. V. Erofeev is with the Institute of High Current Electronics, Siberian Branch of Russian Academy of Sciences, Tomsk 634055, Russia (e-mail: michael@loi.hcei.tsc.ru). cal, photochemical, and photophysical processes, such as the inactivation of microorganisms [1], [2], photolytic processing of metal, dielectric and semiconductor layers, surface cleaning and decomposition of harmful organics [3]–[5]. The absence of mercury in working mixture is another advantage of excilamps which is very important from the ecological point of view. The most promising excilamps are those excited by dielectric barrier discharge (DBD) [6]–[8]. DBD are electric discharges between two metallic electrodes, with at least one of them covered by a dielectric material. Excilamps with two barriers have longer lifetimes due to the absence of direct contact between the working gas mixture and the metallic electrodes.
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Low-temperature and atmospheric pressure sample digestion using dielectric barrier discharge

Low-temperature and atmospheric pressure sample digestion using dielectric barrier discharge

and gas is generated by discharging under atmospheric pressure. 17 − 19 There is no isolation between metal electrodes and wastewater or gas, which could lead to high background intensity because of metal sputtering from electrodes and make it difficult to be utilized in sample digestion. Dielectric barrier discharge (DBD) has a high ionization efficiency, and it is a typical nonequilibrium gas discharge generated between two electrodes which could be isolated by a quartz tube to avoid contamination from metal electrodes to solutions. These features make DBD widely used in an atomic spectrometer as an atomization source. To the best of our knowledge, the research on utilizing low temperature atmospheric pressure DBD plasma in sample digestion has not been reported so far. On the basis of low temperature and low power consumption DBD plasma, the aim of this study was to develop an effective and eco-friendly sample pretreatment method for the sensitive determination of trace elements by one-step digestion without using any oxidizing chemicals or concentrated acids.
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Antifouling pseudo-zwitterionic poly(vinylidene fluoride) membranes with efficient mixed-charge surface grafting via glow dielectric barrier discharge plasma-induced copolymerization

Antifouling pseudo-zwitterionic poly(vinylidene fluoride) membranes with efficient mixed-charge surface grafting via glow dielectric barrier discharge plasma-induced copolymerization

materials satisfy the criteria for ideal antifouling material earlier defined by Whitesides and coworkers [16] , and reminded here: (1) electroneutrality should be ensured; (2) the material should not possess H-bond donors; (3) the material should have H-bond acceptors and (4) it should contain polar functional groups. A new class of materials may satisfy these criteria: the so-called mixed- charge polymers [17 – 22] . These systems are composed of both electronegative and electropositive moieties, and mimic zwitter- ionic polymers. However, as reminded by Edwards and coworkers, mixed-charge polymers functionality are not impacted by the in- troduction of other functional groups [22] . In other words, they are even more stable than zwitterionic materials. These systems have mostly been tested to form antifouling hydrogels or to modify model dense surfaces. Besides their numerous advantages listed by Prof. Jiang's group such as the simplicity of synthesis, the ease of applicability, the numerous potential raw materials as well as the availability of functional groups [18] , these systems allow to investigate the effect of charge bias on protein, bacteria or cell adhesion [23] . This aspect can be of interest for fundamental comprehension of mechanisms at play responsible for biofouling. Yet to the best of our knowledge, only one previous study mentioned the surface modification of polypropylene membranes by mixed-charge polymer [24] . The use of mixed-charges has never been tested using PVDF as a matrix material, very common in membrane commercial applications. Results of such an in- vestigation could be of major interests for the application of membranes in water treatment or blood filtration, two major fields in which in-depth investigations are still required to efficiently mitigate biofouling. This lack of research work suggested the need for a dedicated study. Here, we modified poly(vinylidene fluoride) (PVDF) commercial microfiltration membranes using mixed-char- ges of [2-(methacryloyloxy)ethyl] trimethylammonium (TMA) and 3-sulfopropyl methacrylate (SA). After monomer coating, we ap- plied a new process of glow dielectric barrier discharge (GDBD) plasma treatment to the membranes. Our strategy, schemed in
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Electric and spectroscopic analysis of a pure nitrogen mono-filamentary dielectric barrier discharge (MF-DBD) at 760Torr

Electric and spectroscopic analysis of a pure nitrogen mono-filamentary dielectric barrier discharge (MF-DBD) at 760Torr

Mono-filamentary dielectric barrier discharge ( MF-DBD ), occurring within 1-mm gap of atmospheric pressure pure nitrogen and operating with a sinusoidal electric supply at about 8 kHz, is studied in this paper. A thorough electrical analysis allows experimental determination of the ignition and extinction voltages, respectively (15750 ± 50) V and (2097 ± 7) V, the injected energy (158 ± 2) J and charge (17.22 ± 0.22) nC in a single filament. The mean axial reduced electric field is equal to (644 ± 2) Td at ignition. An empirical technique is proposed to evaluate these discharge parameters by avoiding bulky calculations. Optical emission spectroscopic measurements of the vacuum ultraviolet (VUV), ultraviolet (UV), visible and near infrared (IR) emissions are presented and discussed. Two atomic nitrogen lines attributed to the decay of the N[2s 2 p 2 3s 2 P] triplet towards N[2s 2 2p 3 2 D°] level are observed at 150 and 175 nm, together with the Lyman-Birge-Hopfield system (N 2 [a 1 Π g ]→ N 2 [X 1 Σ + g ]) in the VUV range. The Second Positive system (N 2 [C 3 Π u ]→ N 2 [B 3 Π g ]) dominates the UV and visible-blue spectra. The (0-0) transition of the First Negative system (N 2 + [B 2 Σ + u ]→ N 2 + [X 2 Σ + g ]) peaking at 391.4 nm, the First Positive system (N 2 [B 3 Π g ]→ N 2 [A 3 Σ + u ]) and the Herman infrared transitions (N 2 [C" 5 Π u ]→ N 2 [A' 5 Σ + g ]) also present . Both our VUV and near IR spectra are consistent with recently reported results in hollow cathode and cylindrical DBDs. The electrical and spectroscopic experimental results reported here are useful for ongoing and forthcoming modelling of filamentary nitrogen dielectric barrier discharges.
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Parametric study of dielectric barrier discharge excimer UV lamps supplied with controlled square current pulses

Parametric study of dielectric barrier discharge excimer UV lamps supplied with controlled square current pulses

Keywords: dielectric barrier discharge, excimer lamps, UV emission, power supply, current source. 1. INTRODUCTION UV lamps of Dielectric Barrier Discharge (DBD) structure are environmentally friendly (mercury free) UV sources used for various applications: health, disinfection, surface treatments [1]. The applicability of these DBD excilamps has been demonstrated; today, studies are oriented toward the improvement of their performance. This can be achieved by means of the bulb design (geometry, filling mixture, pressure and materials) [2], [3] and also by selecting the most performing electrical operating conditions [4],[5].These both optimization paths are the purpose of this paper: the characteristics of the candidate bulbs, which performances will be experimentally compared, are presented in §2 and an estimation of the parameters of their equivalent circuit model is displayed. Associated to this set of lamps, the selected power supply, by means of a square shape current source generator is presented in §3: the operating principles of this topology, together with its performances are presented; elements for the design of the actual generator, specifically developed for this study are also proposed. Each bulb under test is connected to this power supply and the operation of the whole system is controlled and monitored by means of a test bench which is described in §0. The measurements achieved on the bench are used for several purposes: firstly, to measure the characteristics of each bulb (§5). Secondly, (§0), the performances obtained with each bulb, under similar supplying conditions, are compared in order to select the lamp and its operating conditions which offer the best results. Comparisons are focused on the efficiencies of: the conversion from electrical power to UV emission, the power supply (input and output powers ratio) and the whole system (energetic efficiency).
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Determination of bismuth by dielectric barrier discharge atomic absorption spectrometry coupled with hydride generation: method optimization and evaluation of analytical performance

Determination of bismuth by dielectric barrier discharge atomic absorption spectrometry coupled with hydride generation: method optimization and evaluation of analytical performance

Dielectric Barrier Discharge Atomizer. A planar configuration of atomizer using a quartz DBD chamber was employed. Its design was based on that recently published by Zhu et al. 2,3 The atomizer was fabricated from two quartz microscope slides (15 mm × 75 mm, 1 mm thickness) and two quartz spacers (3 mm × 3 mm, 75 mm long). All quartz components were purchased from UQG Optics Ltd., England, and fused together. The plasma channel was thus rectangular- shaped with inner dimensions of 7 mm × 3 mm and a length of 75 mm. Two copper electrodes (50 mm long, 12 mm wide, 0.15 mm thick) were attached to the central part of the outer surface of the microscope slides. In order to avoid surface discharge at the outer side of the chamber, the electrode surface was covered with a dielectric layer of epoxy resin. The DBD atomizer was housed in a supporting frame of high-density polyvinyl chloride (PVC). This frame protected the DBD chamber and electrodes from mechanical damage and also facilitated placement of the DBD chamber into the optical axis of the atomic absorption spectrometer. A small computer fan was attached to the bottom of the DBD chamber to provide air cooling. A quartz tube (20 mm long, 2 mm inner diameter, 4 mm outer diameter) was sealed to the center of one of the quartz spacers and served as an inlet arm. A photograph of the DBD atomizer can be seen in Section 1 of the Supporting Information. The DBD and the frame are henceforth termed the DBD chamber. The DBD chamber was coupled to a high- frequency high-voltage generator fabricated by Lifetech (Brno, Czech Republic). The excitation frequency was 25 kHz. To prevent electromagnetic interference, the DBD excitation voltage was fed to the discharge chamber symmetrically, neither electrode was grounded and both were fed with voltage of opposite polarity. The inherent advantage of the generator (necessary for optimization of the experimental conditions) is that the power supplied to the DBD chamber can be controlled
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Antifouling pseudo-zwitterionic poly(vinylidene fluoride) membranes with efficient mixed-charge surface grafting via glow dielectric barrier discharge plasma-induced copolymerization

Antifouling pseudo-zwitterionic poly(vinylidene fluoride) membranes with efficient mixed-charge surface grafting via glow dielectric barrier discharge plasma-induced copolymerization

materials satisfy the criteria for ideal antifouling material earlier defined by Whitesides and coworkers [16] , and reminded here: (1) electroneutrality should be ensured; (2) the material should not possess H-bond donors; (3) the material should have H-bond acceptors and (4) it should contain polar functional groups. A new class of materials may satisfy these criteria: the so-called mixed- charge polymers [17 – 22] . These systems are composed of both electronegative and electropositive moieties, and mimic zwitter- ionic polymers. However, as reminded by Edwards and coworkers, mixed-charge polymers functionality are not impacted by the in- troduction of other functional groups [22] . In other words, they are even more stable than zwitterionic materials. These systems have mostly been tested to form antifouling hydrogels or to modify model dense surfaces. Besides their numerous advantages listed by Prof. Jiang's group such as the simplicity of synthesis, the ease of applicability, the numerous potential raw materials as well as the availability of functional groups [18] , these systems allow to investigate the effect of charge bias on protein, bacteria or cell adhesion [23] . This aspect can be of interest for fundamental comprehension of mechanisms at play responsible for biofouling. Yet to the best of our knowledge, only one previous study mentioned the surface modification of polypropylene membranes by mixed-charge polymer [24] . The use of mixed-charges has never been tested using PVDF as a matrix material, very common in membrane commercial applications. Results of such an in- vestigation could be of major interests for the application of membranes in water treatment or blood filtration, two major fields in which in-depth investigations are still required to efficiently mitigate biofouling. This lack of research work suggested the need for a dedicated study. Here, we modified poly(vinylidene fluoride) (PVDF) commercial microfiltration membranes using mixed-char- ges of [2-(methacryloyloxy)ethyl] trimethylammonium (TMA) and 3-sulfopropyl methacrylate (SA). After monomer coating, we ap- plied a new process of glow dielectric barrier discharge (GDBD) plasma treatment to the membranes. Our strategy, schemed in
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Time resolved imaging of a dielectric barrier discharge by using pulsed power supply

Time resolved imaging of a dielectric barrier discharge by using pulsed power supply

Keywords: Dielectric barrier discharge, Ultraviolet (UV), exciplexes, light sources. 1. Introduction Ultraviolet (UV) sources have been investigated for many years by numerous researchers [1, 2, 3]. However, in these few years, UV sources have become an essential technology in several industrial sectors involving elec- tronics (plasma display), chemical reactions, multilayer techniques and medical treatments (water and skin treat- ment). More recently, excilamps have become an attractive technology for the skin treatment through the application of highly intense UV at the wavelength of 308nm. DBD is an efficient method for stimulating ultraviolet emission from excimer or exciplexes and such UVsources are thus commonly called ‘Excilamps’. There are many different excimers including rare gas excimers (Ar * 2 , Kr
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Atomization of bismuthane in a novel dielectric barrier discharge: a mechanistic study

Atomization of bismuthane in a novel dielectric barrier discharge: a mechanistic study

Atomization of bismuthane in a planar dielectric barrier discharge (DBD) atomizer was investigated using a variety of probes, including atomic absorption spectrometry (AAS) to monitor distribution of free atoms along the optical path and direct analysis in real time (DART) coupled to an Orbitrap mass spectrometer to identify the structure of the species arising from the hydride generator as well as the atomizer. Results obtained with the DBD were compared to those from a conventional externally heated quartz tube atomizer (QTA). Free Bi atoms were essentially absent outside the central part of the DBD atomizer, suggesting their high reactivity. The gas phase analyte fraction transported beyond the confines of the DBD or QTA atomizers, quantified by inductively coupled plasma mass spectrometry (ICP:MS), was less than 10 %. The amount of Bi found in acidic leachates of the interiors of both atomizers, representing the fraction retained on their surfaces, was ca 90 %. These complementary experiments comprising the determination of recovered Bi in the nitric acid leachates from deposition in the atomizer on the one hand and quantification of the Bi fraction transportable outside the atomizer on the other, were in excellent agreement, providing 100 % mass balance of detected analyte. The high fraction of Bi deposited in the atomizers indicates significant reactivity of free Bi atoms, which is in accord with the fact that almost no free Bi atoms exist beyond the physical boundaries of the DBD. The extent of interference from other hydride forming elements (As, Sb, Se) on Bi response by AAS using DBD and QTA atomizers was investigated, with the former atomizer providing superior performance. Compared to QTA, DBD provided two orders of magnitude and one order of magnitude, respectively, better resistance to interference from Se and Sb.
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Investigation on the effect of impurities in xenon based dielectric barrier discharge lamps

Investigation on the effect of impurities in xenon based dielectric barrier discharge lamps

Xenon based discharge has been identified as an alternative candidate to mercury, and as such the authors have used xenon based discharge in an effort to develop mercury- free lamps. Xenon is non-toxic gas and is chemically stable compared to mercury. In low pressure discharge xenon emits strong resonance and excimer emissions in vacuum ultra violet (VUV) regions that can be converted with good efficiency in UV to visible light through phosphor. Xenon low pressure lamps such as exciplex lamp (xenon with halogens) was developed to be used for sterilization and medical treatment[5]. In high pressure discharge it is able to emit strong continuum emissions in visible regions[6], where xenon high pressure arc discharge lamp has been used such as in spectrophotometer. Xenon arc lamp also has a good color rendering with extremely high luminance, for example Osram XBO lamp which has been used for cinema film projection, light guide system, etc. Xenon based discharge also has an advantage in temperature-independence, capable of instant starting and restarting compared to mercury lamps as there is no evaporation process required. Many efforts have been undertaken by a number of researchers using DC, AC or pulse, with conventional type discharge (with electrode), with electrodeless type discharge such as dielectric barrier discharge (DBD), inductively coupled plasma (ICP) and microwave discharge, and their performance has been improving[7-13].
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Elaboration of green bioactive surfaces by combining functionalized plasma layer deposited at atmospheric pressure using a Dielectric Barrier Discharge and covalent immobilization of biomolecules

Elaboration of green bioactive surfaces by combining functionalized plasma layer deposited at atmospheric pressure using a Dielectric Barrier Discharge and covalent immobilization of biomolecules

Among the entrapment methods, some groups developed multi steps methods. Charged polyelectrolyte gels obtained by multilayer wet chemical deposition are a good environment for the immobilization of enzymes. [137] They allow conserving enzymes activities and thermal stabilization through interactions with the gel. Even though enzyme controlled release by pH induced layer decomposition, hydrolysis or charge changes are really interesting properties; the use of such gel for applications as sensing, where time stability is needed, is challenging. To avoid desorption of an alkaline phosphatase (AP) from a polyelectrolyte gel layer of Hyaluronic Acid (HA) and poly-L-lysine (PLL), Amorosi et al. produce a plasma polymerized barrier layer from an atmospheric dielectric barrier discharge, made of plasma polymerized ethylene glycol dimethacrylate (ppEGDMA). The tuning of the plasma parameters allows controlling both the enzyme leaching and the diffusion of paranitrophenyl phosphate (PNP), the targeted chemical compound to react with the enzyme. A thin deposited layer (30 nm), do not avoid the leaching of the enzymes (Figure 13) while increasing of layer thickness tend to allow the retention of the enzyme and a too thick layer (300 nm) reduces the diffusion rate of PNP into the gel for enzymatic reaction. Layers of intermediate thickness allow then the successful entrapment and diffusion of PNP for enzymatic catalysis.
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Ultrasensitive speciation analysis of mercury in rice by headspace solid phase microextraction using porous carbons and gas chromatography-dielectric barrier discharge optical emission spectrometry

Ultrasensitive speciation analysis of mercury in rice by headspace solid phase microextraction using porous carbons and gas chromatography-dielectric barrier discharge optical emission spectrometry

* S Supporting Information ABSTRACT: Rice consumption is a primary pathway for human methyl- mercury (MeHg) exposure in inland mercury mining areas of Asia. In addition, the use of iodomethane, a common fumigant that significantly accelerates the methylation of mercury in soil under sunlight, could increase the MeHg exposure from rice. Conventional hyphenated techniques used for mercury speciation analysis are usually too costly for most developing countries. Consequently, there is an increased interest in the development of sensitive and inexpensive methods for the speciation of mercury in rice. In this work, gas chromatography (GC) coupled to dielectric barrier discharge optical emission spectrometry (DBD-OES) was developed for the speciation analysis of mercury in rice. Prior to GC-DBD-OES analysis, mercury species were derivatized to their volatile species with NaBPh 4 and preconcentrated by
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Estimation of the light output power and efficiency of a XeCl dielectric barrier discharge exciplex lamp using one dimensional drift-diffusion model for various voltage waveforms

Estimation of the light output power and efficiency of a XeCl dielectric barrier discharge exciplex lamp using one dimensional drift-diffusion model for various voltage waveforms

To cite this version: Le, T. Doanh and Bhosle, Sounil and Zissis, Georges and Piquet, Hubert Estimation of the light output power and efficiency of a XeCl dielectric barrier discharge exciplex lamp using one dimensional drift- diffusion model for various voltage waveforms. In: 2011 IEEE Industry Applications Society Annual Meeting, 9-13 October 2011 (Orlando, United States)

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CO2 valorization by means of dielectric barrier discharge

CO2 valorization by means of dielectric barrier discharge

producing hydrogen and CO. It is an endothermic reaction, for which the activition barrier needs to be surpassed. This can be done efficiently by the method of Dielectric Barrier Discharge. The process relies on the collision of electrons, which are accelerated under an electrical field that is created in the discharge area. This leads to the formation of reactive species, which facilitate the abovementioned reaction. This study is performed using a Matlab program with the Reaction Engineering module in COMSOL (with an incorporated kinetic mechanism) in order to model the discharge phase. Then COMSOL (continuity and Navier-Stokes equations) is used to model the flow in the post-discharge phase. The results showed that both a 2D and 3D model can be used to model the chemical-plasma process. These methods need strongly reduced kinetic mechanism, which in some cases can cause loss of precision.
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MDF treatment with a Dielectric Barrier Discharge (DBD) torch

MDF treatment with a Dielectric Barrier Discharge (DBD) torch

Keywords: Dielectric Barrier Discharge, wood, wettability, O/C ratio 1. Introduction Medium density fiberboard (MDF), which is a particular composite forest product (consisting of cellulosic fibers and synthetic resin bonded together), was invented in the United States in the 1960’s as a solid wood substitute. Nowadays, MDF is globally produced on a large scale and widely used in various industries. For example, it is one of the most important and popular materials used in furniture manufacturing, mainly because it can be easily and precisely machined to form complex shapes. This is a result of the fact that MDF is free of structural defects (e.g. knots, shakes or checks) and does not contain any rings, which makes it more uniform, stabile and isotropic than natural wood or plywood. Moreover, it is far more homogeneous than most of other wood-based materials (e.g. ordinary chipboards). In present day, there are a lot of well-known industrial and non-industrial ways of MDF surface finishing (wet painting, powder coating, veneer, melamine, paper or plastic foils, HPL/CPL laminate...), which determine the quality of final products. Regardless of the finishing technology, the wettability of MDF surface plays a crucial role. The positive correlation between wettability and adhesive properties of wood and wood-based materials is evident [1-7].
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Synthesized High-Frequency Thyristor for Dielectric Barrier Discharge Excimer Lamps

Synthesized High-Frequency Thyristor for Dielectric Barrier Discharge Excimer Lamps

Synthesized High-Frequency Thyristor for Dielectric Barrier Discharge Excimer Lamps Marc Cousineau, Member, IEEE, Rafael Díez, Member, IEEE, Hubert Piquet, and Olivier Durrieu Abstract—Dielectric barrier discharge (DBD) lamps, being ca- pacitive loads, must be associated with bidirectional current sources for an appropriate control of the transferred power. Pulsed current source supplies, which are known to offer very interesting performances, require specific power switches that are able to manage bidirectional voltage and unidirectional current at much higher frequencies (several hundreds of kilohertz) than commer- cial thyristors. This paper proposes the detailed design of such a high-speed synthesized thyristor, using discrete components: a MOSFET in series with a high-voltage (HV) diode and a logic circuit that controls its gate. This switch is associated with an optimized self-powered driver, which is a very efficient solution to handle the perturbations associated with the HV and high- frequency operation. Experimental application of this device for DBD excimer lamp supply is proposed.
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