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Sensitization phenomena by gliding arc discharge: Experimental and Modeling study

Sensitization phenomena by gliding arc discharge: Experimental and Modeling study

Eqs. (5)–(7) demonstrated that vibrationally/rotationally excited water molecules relax into a lower energetic state through which some active radicals can be produced.(A) I.6.2 Plasma species : Considering the cold plasma and especially the gliding arc discharge with humid air composed of 50% of water (H2O) and 50% of air, (as a reminder, the composition of the air is, in a very simplified way, of 21% dioxygen and 79% dinitrogen). This gas passes between the electrodes of the GAD, forming a purple plume due to contact with the electric current. this plume results in the formation of the primary plasmagenic species (cations, anions and neutral species). Generally these species have a great energetic state which allows it to react with each other which expresses its short lifetimes. the reactions between the primary species induce the formation of the secondary plasmagenic species classify in two category RNS [58] due to the presence of nitrogen and ROS due to the presence of oxygen, these species penetrate into the liquid where they present oxidizing effects and acidifying which can degrade the pollutants present in the liquid. all the plasmagenic species in the different regions are presented in table
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Gliding arc plasma assisted photocatalytic degradation of anthraquinonic acid green 25 in solution with TiO2

Gliding arc plasma assisted photocatalytic degradation of anthraquinonic acid green 25 in solution with TiO2

8 Résumé : Anthraquinonic acid green 25 (AG 25) removal was investigated by plasma chemistry using non-thermal gliding arc at atmospheric pressure. The gaseous species formed in the discharge, and especially OH radicals, induce strong oxidizing effects in the target solution. The removal of the dye was carried out in the absence and presence of TiO 2 as

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New prototype for the treatment of falling film liquid effluents by gliding arc discharge part I: Application to the discoloration and degradation of anthraquinonic Acid Green 25

New prototype for the treatment of falling film liquid effluents by gliding arc discharge part I: Application to the discoloration and degradation of anthraquinonic Acid Green 25

[35] F. Moras, D. Seguin, B. Benstaali, A. Addou, B.G. Cheron, E. Hnatiuc, J.L. Brisset, Interaction between a non-thermal oxygenated plasma and aqueous solutions, in: Proceedings of International Conference HAKONE, 2000. [36] R. Burlicaa, M.J. Kirkpatrickb, B.R. Lockeb, Formation of reactive species in gliding arc discharges with liquid water, Journal of Electrostatics 62 (2004) 309–321.

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Enhancement of the bleaching and degradation of textile wastewaters by gliding arc discharge plasma in the presence of TiO2 catalyst

Enhancement of the bleaching and degradation of textile wastewaters by gliding arc discharge plasma in the presence of TiO2 catalyst

The degradation of two polluted textile wastewaters from SOITEX (silk and textile) industry using the plasma-catalytic process, has been studied by non-thermal Gliding arc technique co[r]

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Plasma treatment by gliding arc discharge of dyes/dye mixtures in the presence of inorganic salts

Plasma treatment by gliding arc discharge of dyes/dye mixtures in the presence of inorganic salts

OH and NO  radicals ( Benstaali et al., 2002 ). Therefore, the aim of this study is to use the same technique and investigate the discoloration and degradation by gliding arc discharge (GAD) produced reactive species on aqueous solutions of an anthraquinone dye, Alizarin red S (ARS), an azo dye Orange G (OG) and their mixture in different propor- tions. The study also focused on the influence of chlorides and sulfates often present in textile wastewaters. Both dyes are extensively used in the textile industry and are considered mutagenic poisons, suspected of being carcinogenic ( Zucca et al., 2008; Lachheb et al., 2002; Xu and Li, 2010 ).
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Acidity control of the gliding arc treatments of aqueous solutions: application to pollutant abatement and biodecontamination

Acidity control of the gliding arc treatments of aqueous solutions: application to pollutant abatement and biodecontamination

and the pH substantially lowered. This “acid effect” de- pends on the main working parameters and may be easily quantified. Among the chemical properties induced in the solution by a plasma treatment in air, acidity measurements are an easy-to-operate diagnostic. An increase in the acidity of the solvent target exposed to a humid air plasma is ob- served and confirms previous observations on the corona discharge [15–17]. We now focus on the treatment of aque- ous solutions by a gliding arc in humid air.

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Plasma treatment of aqueous solutes: some chemical properties of a gliding arc in humid air

Plasma treatment of aqueous solutes: some chemical properties of a gliding arc in humid air

conditions. A typical illustration is the corona discharge, but other plasmas belong to this intermediate class of dis- charges, such as the gliding arc (or “glidarc”) discharge [1]. Due to its dual character of thermal and “cold” plasma, the glidarc presents an attractive feature for both scien- tific and industrial points of view. The scientist is inter- ested in modelizing [2] such an unusual plasma, and the industrial in new treatments performed at atmospheric pressure. Since most of the plasma treatments of materi- als are related to the chemical properties of the plasmas, these properties appear as a fundamental aspect which must be examined in chemical terms.
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Gliding arc plasma assisted photocatalytic degradation of anthraquinonic acid green 25 in solution with TiO2

Gliding arc plasma assisted photocatalytic degradation of anthraquinonic acid green 25 in solution with TiO2

that of the gas used. The activated species are atoms (O), radicals (OH  ) or excited molecules (singlet oxygen O 2 1 Dg). In the latter case, a modified electron distribution induces a modified and usually enhanced reactivity. Emission spectro- scopy measurements on gliding arc plasma in humid air revealed the simultaneous presence of OH  and NO  radicals in the discharge, with a much higher density for OH  radicals than for NO  [20] . The species formed in gliding arc discharge such as OH  radicals are responsible for strong oxidizing effects whereas NO  radicals for acidifying properties [21–23] .
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Influence of peroxynitrite in gliding arc discharge treatment of alizarin red s and postdischarge effects

Influence of peroxynitrite in gliding arc discharge treatment of alizarin red s and postdischarge effects

ABSTRACT: The gliding arc discharge is a cheap and e fficient nonthermal plasma technique able to degrade organic compounds dispersed in water at atmospheric pressure. Alizarin Red Sulfonate (ARS) is selected as a stable quinonic dye. Exposure of the dye solution to the discharge in a batch reactor induces two successive reaction steps according to the treatment conditions. Direct exposure of the solution to the discharge induces simultaneous bleaching and COD evolution. In postdischarge conditions, that is, after the discharge is switched o ff, the reactions keep on developing. This study thus underlines two key features: the ability of glidarc discharges to degrade recalcitrant molecules and the low cost of the process which requires short exposure times. A model mechanism involves peroxynitrite as a likely active species formed in the discharge and involved in postdischarge phenomena in aqueous solutions and suggests short exposure times and much longer postdischarge times for optimized pollutant abatement.
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Gliding arc discharge (GAD) assisted catalytic degradation of bisphenol A in solution with ferrous ions

Gliding arc discharge (GAD) assisted catalytic degradation of bisphenol A in solution with ferrous ions

The degradation of an endocrine disruptor (ED), the bisphenol A (BPA), was studied using Gliding Arc Discharge (GAD). This kind of discharge generates a non-thermal plasma at atmospheric pressure and quasi-ambient temperature. The resulting plasma is the source of several chemical reactions that lead to the hydroxyl radical formation. Hydroxyl radicals, • OH, are very powerful and non-selective oxidizing agents (E ◦

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Dynamic Arc-Flags in Road Networks

Dynamic Arc-Flags in Road Networks

We experimentally analyze the proposed algorithms in real-world road net- works showing that, in comparison to the recomputation from-scratch of Arc- Flags, they yield a significant speed-up in the updating phase of Arc-Flags, at the cost of a little space and time overhead in the preprocessing phase. In detail, we experimentally show that our algorithm updates the Arc-Flags at least 62 times faster than the recomputation from scratch in average, considering the graph where the new algorithm performs worse. Moreover it performs better when the network is big, hence it can be effectively used in real-world scenarios. In order to compute and store the Road-Signs, we need an overhead in the pre- processing phase and in the space occupancy. However, we experimentally show that such an overhead is very small compared to the speed-up gained in the up- dating phase. In fact, considering the graph where the new algorithm performs worse, the preprocessing requires about 2.45 and 2.88 times the time and the space required by Arc-Flags, respectively.
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Theoretical Analysis of Singleton Arc Consistency

Theoretical Analysis of Singleton Arc Consistency

7 Summary and Conclusion We have made a theoretical study of singleton arc consistency. We have proposed a SAC algorithm having optimal worst case time complexity. We have observed some bad behaviors of SAC. These observations have led us to conclude that SAC is definitely not as ’local’ as the other local consistencies, with some bad consequences on the way to efficiently enforce it. Another consequence is that we can enhance the pruning efficiency of SAC by changing its definition to avoid one of its observed drawbacks. The filtering capability of the new local consistency obtained is also studied.
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Hopf algebras on decorated noncrossing arc diagrams

Hopf algebras on decorated noncrossing arc diagrams

U caV bW where a < b < c are letters while U, V, W are words on N. The objective of the present work is to discuss similar Hopf algebra structures on congruence classes of all lattice quotients of the weak order on Sn. Several examples of relevant combina- torial structures arise from lattice quotients of the weak order. The fundamental example is the Tamari lattice introduced by D. Tamari in [ Tam51 ] and largely studied since then (see the survey book [ MHPS12 ]). It can be defined as the transitive closure of right rotations on binary trees. It is also (isomorphic to) the quotient of the weak order on Sn by the above-mentioned sylvester congruence. See Figure 1 . Many other relevant lattice quotients of the weak order have been studied, see in particular [ Rea06 , CP17 , PP18 , LR12 , Gir12 , Law14 , Pil18 ]. N. Reading provided in [ Rea15 ] a powerful combinatorial description of the lattice congruences of the weak order and of their congruence classes in terms of collections of certain arcs and noncrossing arc diagrams.
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Lightning arc interaction with complex structure

Lightning arc interaction with complex structure

• Constrained arc: • Phase 1: Arc root expansion constrained by paint with Ø Constrained arc ≤ Ø free arc • Phase 2: Arc root expansion dependent on LSP conductivity (anisotropic) with Ø Constrained arc > Ø free arc • It is aimed here to evaluate this assertion through the comparison of experimental measurements of the vaporization radii for different painting configurations with numerical predictions.

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Recherche culturelle et sciences participatives PARTICIP-ARC

Recherche culturelle et sciences participatives PARTICIP-ARC

Sciences participatives, Sciences/recherches collaboratives, Sciences/recherches contributives, Recherche-action participative, Recherche interventionnelle, Community based research, Recherche communautaire ; arts communautaires, interactifs, interventionnistes, socialement engagés (cf. Point de vue Peter Sinclair ci-dessous) ; épidémiologie populaire en médecine… Beaucoup de termes sont utilisés. Muki Haklay (2015) a tenté une catégorisation des niveaux de participation, mais il faut surtout souligner que les sciences participatives sont en évolution constante, et pas uniquement d’un point de vue du numérique. Si les relations entre amateurs et disciplines scientifiques sont anciennes, elles ont des ancrages historiques forts : « amateurat » en écologie (en taxonomie aujourd’hui, les personnes en capacité d’identifier certaines espèces sont très souvent des amateurs), mouvement de la recherche-action (ancien en sciences humaines et sociales), mobilisation collective de malades (partie intégrante de l’histoire des sciences médicales), community based research (conflits entre Etats et populations autochtones qui souhaitent se faire entendre et faire reconnaître leurs savoirs), aménagement urbain participatif (corrélés à des mouvements sociaux depuis les années 1960)… Cette pluralité d’épistémologies et de cadres théoriques produisent parfois des tensions et des concurrences. Elle relève de visions du monde assez différentes, sur la place des savoirs notamment. Elle relève aussi de contextes politiques mettant en avant rationalité scientifique ou savoirs locaux. Derrière chaque terme employé, il y a une ou plusieurs communauté(s) de référence, des prises de positions méthodologiques, théoriques et axiologiques. La « recherche culturelle et sciences participatives » est un domaine hétérogène où chaque projet est ancré dans une épistémologie. Le Muséum est davantage familier de la recherche-action participative et du modèle Citizen Science, incarné par Vigie-Nature, mais Particip-Arc est une ouverture aux autres domaines.
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Recherche Culturelle et Sciences Participatives PARTICIP-ARC

Recherche Culturelle et Sciences Participatives PARTICIP-ARC

La question du sens et de la pertinence Si un certain engouement scientifique voire politique est observé pour les sciences participatives, dans le cadre plus large du développement de la participation du public dans tous les domaines, la qualité et le succès du projet tiennent dans son sens et sa pertinence : avancées scientifiques (élargissement des questionnements, des possibilités de recueil de données d’un point de vue quantitatif et qualitatif…), retombées des résultats scientifiques sur la société, sensibilisation des participants à la démarche scientifique ou mobilisation sur le partage, l’étude et la préservation de l’objet de la recherche (une langue, un patrimoine, une mémoire…). Il apparaît que la dimension culturelle induit presque toujours un « concernement » par au moins une partie des publics participants. Les partenaires du réseau Particip-Arc formulent le souhait que les projets se développent dans le sens d’un engagement croissant de nouveaux acteurs et de nouvelles communautés, au-delà des publics déjà actifs.
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Making Bound Consistency as Effective as Arc Consistency

Making Bound Consistency as Effective as Arc Consistency

1 Introduction Constraint solvers work by interleaving branching with con- straint propagation. Arc consistency (AC) and bound consis- tency (BC) are the most common kinds of constraint propaga- tion that solvers enforce. BC is used on a constraint when AC is too expensive. This happens when domains are too large, or when AC is too hard to enforce on the constraint. For in- stance, given n variables and d values per domain, the alldiff constraint can be made BC in O(n · log(n)) time ([Puget, 1998]) whereas O(n 1.5 d) time is required for AC ([R´egin,

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Arc Routing Problems for Road Network Maintenance

Arc Routing Problems for Road Network Maintenance

match the temperature conditions in different zones with the probability of the presence of black- ice and plan a circuit for the patrol. Rescheduling of salt spreading - snow plowing operations: Snow removal and salt spreading, the most common activities in winter maintenance, are often performed for each storm event on a repetitive basis over the same routes until safe mobility conditions are achieved (Campbell, Langevin, and Perrier, 2014). In practice master schedules are usually constructed by solving deterministic capacitated arc routing instances based on average demands predicted by the weather conditions. The master schedules should be executed as they were established if no unexpected events occur. However, disruptions may occur, especially in winter, which may interrupt the master plans. When a disruption occurs, routes should be quickly revised to minimise the negative impact it may cause and to ensure the quality of service. The case of adjusting an initial itinerary after one or more vehicle breakdowns during the execution stage is considered in this research.
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Adaptive network flow with $k$-Arc Destruction

Adaptive network flow with $k$-Arc Destruction

Let k be a positive integer. We consider that the number of destroyed arcs is fixed to k, and that A ′ can be any subset of k arcs. Then the problem k-AMRFP is defined as follows: Adaptive Maximum Residual Flow with k-Arc Destruction Problem (k-AMRFP) INSTANCE: A directed network G = (V, A, c) with a source s ∈ V and a sink t ∈ V .

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Système intelligent d'aide au contrôle de procédé dans un four à arc

Système intelligent d'aide au contrôle de procédé dans un four à arc

Ainsi, nous avons été en mesure de mettre en place une base de règles qui permettent, en utilisant des données en temps réel et des modèles mathématiques utilisant les paramètres électri[r]

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