Bibliografías temáticas / Catalyse profane

Literatura académica sobre el tema "Catalyse profane"

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Publicado: 20 de abril de 2024

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Artículos de revistas sobre el tema "Catalyse profane"

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Liubas, N. M., R. Ya Iskra, B. І. Kotyk, N. Ya Monka y V. I. Lubenets. "Prooxidant-antioxidant profile in tissues of rats under the action of thiosulfonate esters". Ukrainian Biochemical Journal 94, n.º 6 (23 de febrero de 2023): 18–29. http://dx.doi.org/10.15407/ubj94.06.018.

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Thiosulfonates are characterized by a wide spectrum of biological activity and have effective antimicrobial, antithrombotic, antitumor and antiparasitic effects. However, the use of synthetic sulfur-containing compounds for therapeutic and preventive purposes requires the study of their effect on the protective mechanisms of maintaining homeostasis, the antioxidant status of the body in particular. The aim of the study was to estimate lipid peroxidation process and the state of the antioxidant system in the kidneys, spleen, brain, and muscles of rats under the influence of newly synthesized sulfur-containing compounds of S-alkyl esters of thiosulfonic acids S-ethyl-4-aminobenzenethiosulfonate (ETS), S-allyl-4-aminobenzenethiosulfonate (ATS) and S-allyl-4-acetylaminobenzenethiosulfonate (AATS). Male Wistar rats kept on a standard diet were divided into four groups of 5 animals each: I (control), II, III, IV (experimental). The animals of the control group received additional 0.5 ml of oil and the animals of the experimental groups 0.5 ml of oil solution of thiosulfonate esters once a day. The animals of II, III and IV groups were given ETS, ATS, AATS at the rate of 100 mg per kg of body weight. The lipid hydroperoxides (LPH), TBA-active products, GSH content and activity of SOD, catalase, glutathione peroxidase, glutathione reductase in tissue homogenates were determined. The multidirectional changes of the studied indicators after consumption of S-alkyl esters of thiosulfonic acids for 21 days have been identified and characterized indicating on different degree of inhibition or activation of LPO processes depending on the type of tissue and the structure of thiosulfonate ester. Keywords: antioxidant system, rat tissues, S-allyl-4-acetylaminobenzenethiosulfonate, S-allyl-4-aminobenzenethiosulfonate, S-ethyl-4-aminobenzenethiosulfonate
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Tesis sobre el tema "Catalyse profane"

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Naudon, Frederic. "Analyses sociologique et expérimentale de la contribution de profanes-néophytes à la démocratie technique : le déploiement d’une filière hydrogène-énergie en Normandie". Electronic Thesis or Diss., Normandie, 2022. http://www.theses.fr/2022NORMC038.

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Une personne n’ayant pas de connaissances particulières dans un domaine — i.e. un profane-néophyte — est-elle capable d’aider un spécialiste de ce domaine à produire de nouvelles connaissances ? Cette question trouve son origine dans le croisement de deux champs disciplinaires : l’étude des effets de la vulgarisation scientifique sur les chercheurs qui vulgarisent leur propre sujet d’études et les recherches sur les dispositifs de démocratie technique de type conférence de citoyens. De nombreuses traces tangibles de pertinence de la part du « grand public » et des citoyens « ordinaires », principalement sous forme de témoignages, laissent penser que la rencontre avec des profanes-néophytes peut constituer une ressource cognitive originale. Pour explorer cette question, nous étudions la relation entre le(s) spécialiste(s) d’un domaine et des non-spécialistes de ce domaine.La première modalité de recherche est une enquête qualitative auprès des acteurs du déploiement d’une filière hydrogène-énergie en Normandie (observations directes, entretiens et analyse de documents-clés). La seconde repose sur des dispositifs expérimentaux visant à confirmer ou infirmer l’idée que les profanes-néophytes peuvent être des acteurs de la réflexion aux côtés des spécialistes, dans deux contextes réputés pour leur complexité : la recherche scientifique (réunions de laboratoire intégrant des profanes-néophytes) et l’implantation d’une nouvelle technologie dans un territoire (réunions interdisciplinaires pour le projet d’un bateau-école électrique à hydrogène dans un lycée maritime). Ce travail montre qu’un profane-néophyte possède une capacité à penser libre de certains freins liés à la connaissance du sujet et qu’il est ainsi en mesure de donner de la mobilité au spécialiste par rapport à son sujet. Le facteur limitant est du côté du spécialiste dont la posture, en particulier l’humilité et l’ouverture à l’autre, joue un rôle déterminant
Is a person with no particular knowledge in a field – i.e. a layperson-neophyte – able to help a specialist in that field to produce new knowledge? This question originates from the intersection of two disciplinary fields: the study of the effects of scientific popularization on researchers who popularize their own subject of study and research on technical democracy devices such as citizen conferences. Many obvious traces of relevance from the general public and "ordinary" citizens, mainly in the form of testimonials, suggest that encounters with laypersons-neophytes can be an original cognitive resource. To explore this question, we study the relationship between field specialist(s) and non-specialists of the same field.The first research method is a qualitative survey of the actors involved in the deployment of a hydrogen-energy sector in Normandy (direct observations, interviews and analysis of key documents). The second method is based on experimental devices aiming at confirming or disproving the idea that laypersons-neophytes can be actors of reflection alongside specialists, in two contexts renowned for their complexity: scientific research (laboratory meetings integrating laypersons-neophytes) and the implementation of a new technology in a territory (interdisciplinary meetings about the project of an electric hydrogen training-boat in a professional fishing school). This work shows that a layperson-neophyte possesses a capacity to think clear of specific brakes linked to the knowledge of the subject. It shows also that the layperson is able to give the specialist more mobility in relation to his subject. The limiting factor is on the side of the specialist’s responsibility: his approach, particularly with humility and openness to others, plays a determining role
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Harris, Gari Stuart. "Surface profile imaging of spinel catalysts". Thesis, University of Oxford, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.258433.

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Guérard, Patrick. "Hydroconversion thermocatalytique profonde des pétroles lourds en présence de catalyseur dispersé à base de molybdène : étude du procédé en unité micropilote". Aix-Marseille 3, 1993. http://www.theses.fr/1993AIX30069.

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La valorisation des petroles lourds est devenu un probleme important en raison de la modification structurelle du marche des produits petroliers. Les procedes d'hydroconversion avec catalyseurs en suspension ne sont pas confrontes au probleme de desactivation du catalyseur et sont bien adaptes au traitement de ce type de petrole. L'hydroconversion thermocatalytique en presence de catalyseur disperse a base de molybdene (precurseur catalytique: naphtenate de molybdene) en unite micropilote continue a permis d'obtenir la conversion profonde (superieure a 85%) du residu sous vide safaniya tout en assurant un controle efficace de la production de coke. Le procede decrit permet une desulfuration et une demetallisation importantes de la charge petroliere. Neanmoins, la desazotation n'a pratiquement pas lieu. La reaction necessite des conditions de severite (temperature, temps de passage) elevees. La technologie doit etre particulierement adaptee pour permettre la mise en uvre du catalyseur disperse solide sans difficultes (circulation, maintien en suspension). La caracterisation des effluents liquides et des differentes fractions issue des techniques de desalphaltage, distillation et chromatographie liquide a mis en evidence le mode d'action du catalyseur disperse. Celui-ci permet d'amplifier les reactions de dealkylation des structures aro et polyaromatiques, l'hydrogenation partielle ou totale des noyaux aromatiques et des heterocycles permettant ainsi l'hydrogenolyse des liaisons c-s et c-n. Il favorise egalement la desagregation des resines et asphaltenes generalement refractaires au traitement
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Elmouchnino, Jeanne. "Hydroconversion profonde d'huiles lourdes de petrole en presence de catalyseur disperse a base de molybdene". Paris 6, 1992. http://www.theses.fr/1992PA066135.

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Cette etude a analyse le comportement d'une huile lourde de petrole (residu-sous-vide de safaniya) lors de sa pyrolyse dans le but de promouvoir sa conversion profonde en distillats legers (80%). Cette transformation est realisee sous pression d'hydrogene en presence de catalyseur disperse a base de molybdene genere in situ au cours du traitement a partir de l'acide phosphomolybdique. Les mecanismes thermochimiques ont ete abordes par l'etude de composes-modeles. La transformation du petrole est jugee se derouler selon trois phases de conversions croissantes, l'effet du catalyseur etant plus marque au cours des phases 2 et 3. L'amelioration qualitative de la transformation en particulier au niveau du controle de la formation de coke, de la conversion des fractions les plus lourdes et de la desulfuration est attribuable a une action de transfert d'hydrogene, des capacites hydrogenolysante et hydrogenante de la part du catalyseur disperse fortement dependante de sa quantite. Diverses techniques analytiques (pyroanalyse oxydante, gpc, rmn, microscopie optique, rpe), appliquees aux liquides, aux asphaltenes et aux cokes, ont ete employees. L'emploi d'une etape de pretraitement ameliore la qualite de la transformation de la recette de la pyrolyse ulterieure. L'association catalyseur disperse-compose polyaromatique (pyrene, slurry catalytique) est responsable d'un effet de synergie au niveau du controle de la formation de coke. Ces deux modifications permettent de reduire la quantite de precurseur catalytique a engager. L'etude du 9-dodecylphenanthrene permet de quantifier une activite hydrogenante moderee du catalyseur mais induisant un accroissement en produits tetrahydrogenes. Par ailleurs, la conversion du compose est peu affectee par la presence de catalyseur, cependant la distribution des produits est largement modifiee avec principalement l'annulation de la formation de composes a hauts poids moleculaires. Cette tendance montre que le catalyseur est a l'origine de l'inhibition de certaines voies reactionnelles conduisant, dans le cas du petrole, a du coke. L'etude de reactions regissant la formation de semi-coke a ete effectuee a partir des oligomeres de l'acenaphtylene. Le faible ecart entre les essais thermiques (sous hydrogene) et thermocatalytiques montre, au contraire, l'inefficacite du catalyseur sur certains types de reactions (electrocyclisations, condensations radicalaires a cinetiques rapides) rendant compte pour le petrole d'une fraction incompressible de coke
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Lin, Zong-Bin y 林棕斌. "Selective hydrogenation of isoprene by using palladium eggshell profile catalyst". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/65995922537538848564.

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Kauser, Sobia, Gillian E. Westgate, M. R. Green y Desmond J. Tobin. "Human Hair Follicle and Epidermal Melanocytes Exhibit Striking Differences in Their Aging Profile which Involves Catalase". 2011. http://hdl.handle.net/10454/7453.

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no
Canities or senile hair graying, a universally recognized sign of aging, remains unresolved in terms of physiological causes, although a strong genetic contribution is understood (Gunn et al., 2009). As the hair fiber continues to grow long after melanin production ceases, we suggest that melanocytes in the hair follicle may be more sensitive to the impact of chronological aging than are keratinocytes. Moreover, follicular melanocytes also age more markedly than those in the overlying epidermis. The hair follicle provides a unique opportunity to decouple the impact of age on two hair follicular tissue functions: hair formation and hair pigmentation. ... This study provides analysis of race, age, and anatomically matched cultures of adult human epidermal and hair follicle melanocytes (HFMs).
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Libros sobre el tema "Catalyse profane"

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Prinz, Emanuel. Movement Catalysts: Profile of an Apostolic Leader. Carey Publishing, William, 2021.

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Whitlinger, Claire. Between Remembrance and Repair. University of North Carolina Press, 2020. http://dx.doi.org/10.5149/northcarolina/9781469656335.001.0001.

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Few places are more notorious for civil rights–era violence than Philadelphia, Mississippi, the site of the 1964 “Mississippi Burning” murders. Yet in a striking turn of events, Philadelphia has become a beacon in Mississippi’s racial reckoning in the decades since. Claire Whitlinger investigates how this community came to acknowledge its past, offering significant insight into the social impacts of commemoration. Examining two commemorations around key anniversaries of the murders held in 1989 and 2004, Whitlinger shows the differences in how those events unfolded. She also charts how the 2004 commemoration offered a springboard for the trial of former Klan leader Edgar Ray Killen for his role in the 1964 murders, the 2006 passage of Mississippi’s Civil Rights/Human Rights education bill, and the initiation of the Mississippi Truth Project. In doing so, Whitlinger provides the first comprehensive account of these high profile events and expands our understanding of how commemorations both emerge out of and catalyze associated memory movements. Threading a compelling story with theoretical insights, Whitlinger delivers a study that will help scholars, students, and activists alike better understand the dynamics of commemorating difficult pasts, commemorative practices in general, and the links between memory, race, and social change.
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Capítulos de libros sobre el tema "Catalyse profane"

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Beyerlein, R. A., G. A. Tamborski, C. L. Marshall, B. L. Meyers, J. B. Hall y B. J. Huggins. "Monitoring Fluid Cracking Catalyst Deactivation Profile by Equilibrium Catalyst Separation". En ACS Symposium Series, 109–43. Washington, DC: American Chemical Society, 1991. http://dx.doi.org/10.1021/bk-1991-0452.ch008.

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Chen, P. y G. Liu. "1.4 Copper-Catalyzed C—H Functionalization via Radicals". En Base-Metal Catalysis 1. Stuttgart: Georg Thieme Verlag KG, 2023. http://dx.doi.org/10.1055/sos-sd-238-00075.

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AbstractThe direct functionalization of C—H bonds is highly attractive due to its efficiency for converting simple molecules into a wide range of valuable organic compounds. Among available strategies, radical C—H functionalization via hydrogen-atom transfer (HAT) represents one of the most powerful approaches and allows a unique profile of reactivity and selectivity. In this review, copper-catalyzed C—H functionalizations via radicals are summarized, including C—H cyanation, arylation, alkynylation, fluoroalkylation, amination, and oxygenation. It is worth noting that the combination of chiral ligands and chiral phosphoric acids with copper catalysis enables the enantioselective functionalization of radicals.
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Doraiswamy, L. K. "Reactor Design for Solid-Catalyzed Fluid-Phase Reactions". En Organic Synthesis Engineering. Oxford University Press, 2001. http://dx.doi.org/10.1093/oso/9780195096897.003.0019.

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Catalytic reactions are carried out in reactors with a fixed, fluidized, or moving bed of catalyst. Although the chemical kinetics of the reaction obviously remains the same for all these reactors, the hydrodynamic features vary considerably. Because no complete description of these features is possible, it is convenient to postulate different situations and develop mathematical models to represent these situations for each type of reactor. It is also important to note that wherever solid catalysts are used, the question of catalyst deactivation cannot be ignored. Several books and reviews covering a variety of situations have been written, including those marked with an asterisk in the list of references. They are recommended for general reading. Our intention in this chapter is limited, however: formulate approaches to the design of two main classes of catalytic reactors, fixed and fluidized bed; briefly describe selected procedures along with a few numerical (or methodological) examples to illustrate their use; and outline a procedure for incorporating the effects of catalyst deactivation in reactor design and operation. There are basically two types of fixed-bed reactors: (1) multitubular, in which tubes of approximately 1.5 to 4.0 cm in diameter are placed as a bundle within a shell through which a heat exchange fluid is circulated to control the temperature profile within the reactor; and (2) adiabatic, in which the catalyst is placed directly inside a reactor (with no a priori limitation to the diameter), and heat removal is accomplished by multistaging the bed and removing the heat of reaction by heat exchange between stages. Four major models have been proposed for describing the behavior of a packed tubular reactor (see Doraiswamy and Sharma, 1984). Of these, the most extensively used is the quasi-continuum model in which the fluid-solid system is assumed to act as a single pseudohomogeneous phase with effective properties of its own (as for any true single phase). Thus the procedures developed in Chapters 4 and 10 for the homogeneous model can be used to determine the axial profiles of concentration and temperature. One can also allow for radial transport gradients within each tube [two-dimensional (2-D) models], as opposed to the simpler models in which these gradients are neglected—the one-dimensional (1-D) models.
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Ammer, Ch y Ch Teichert. "Spot Profile Analysis for Studying Epitaxial Growth". En Studies in Surface Science and Catalysis, 237–39. Elsevier, 1988. http://dx.doi.org/10.1016/s0167-2991(08)65052-1.

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Follestad, Arild, Stein Helleborg y Vidar Almquist. "6. Kinetic Profile of Polymerization with Cr-Oxide/SiO2 Catalyst". En Catalytic Olefin Polymerization, Proceedings of the International Symposium on Recent Developments in Olefin Polymerization Catalysts, 63–85. Elsevier, 1990. http://dx.doi.org/10.1016/s0167-2991(08)61617-1.

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"Black Lives Still Matter (2020)". En Advances in Public Policy and Administration, 96–130. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-7343-3.ch005.

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This chapter explains the fomentation of the Black Lives Matter movement, which began as a hashtag in 2013. The chapter explores the ideology and goals of the movement, as well as past and current tactics that the movement participants are utilizing to bring awareness to their cause. The chapter highlights numerous high-profile incidents that propelled Black Lives Matter onto the national stage and that have kept it in the public eye, including the most recent catalyst, George Floyd (2020).
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Dallara, Antonio y Denis Grasso. "Analysis of New Sustainable Mobility Solutions for Maritime Passengers Transport". En Priorities for the Sustainability of Maritime and Coastal Passenger Transport in Europe. Venice: Fondazione Università Ca’ Foscari, 2022. http://dx.doi.org/10.30687/978-88-6969-617-6/002.

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This chapter aims to describe new sustainable people’s mobility solutions, in the field of maritime cross-border transport. The review proposed here extends beyond the typical review of technological solutions. Starting from the need to profile the cross-border traveller and the overall context, four possible strategies for reducing the environmental impact of a transport system are identified. Technology is an important catalyst of sustainable transport strategy but the changes in behaviours, the adoption of data-based planning process and the definition of targeted policy measures (e.g., soft measures adoption) are important as well.
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Kovalchuk, V. y V. Soroka. "TRAINING OF MOTOR VEHICLE PROFILE SPECIALISTS IN THE CONDITIONS OF DIGITALIZATION". En Pedagogical concept and its features, social work and linguology (2nd ed.). 2a ed. Primedia eLaunch LLC, 2021. http://dx.doi.org/10.36074/pcaifswal.ed-2.01.

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The urgency of the digitalization process is directly related to the need for the transition of society around the world to a new level of development, and the catalyst for this process is the formation of general digital literacy as a component of digital competence and readiness to use digital technologies in professional activities. The article analyzes the main trends in the digitalization of vocational (technical) education and highlights the main aspects of modern development of the automotive industry. The system of training of specialists of motor transport profile and innovative pedagogical technologies, which are used for their training in institutions of professional (vocational) education, are investigated. The main competencies that should be possessed by a competitive specialist in the field of motor transport in the digital age are highlighted. Modern learning technologies are considered, with an emphasis on digitalization and features of the modern young generation Z, which are used to form the competencies of specialists in the field of motor transport.
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Basile, F., G. Fornasari, F. Trifirò y A. Vaccari. "Reactivity and thermal profile of methane partial oxidation at very short residence time". En Studies in Surface Science and Catalysis, 449–54. Elsevier, 2000. http://dx.doi.org/10.1016/s0167-2991(00)80998-2.

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Däweritz, L., R. Hey y H. Berger. "Defect Structure Characterization of MBE-Groivn GaAs(OO1) Surfaces by Rheed Intensity Profile Analysis". En Studies in Surface Science and Catalysis, 194–96. Elsevier, 1988. http://dx.doi.org/10.1016/s0167-2991(08)65039-9.

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Actas de conferencias sobre el tema "Catalyse profane"

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Rożeń, Antoni. "A Simple One-Dimensional Model of a Passive Hydrogen Recombiner". En 2014 22nd International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/icone22-31124.

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A simple one-dimensional model allowing fast predictions of: a gas composition and temperature profiles, a catalyst temperature profile and an overall hydrogen recombination degree has been developed for a passive catalytic recombiner. The model assumes that heat and mass transport processes, taking place in vertical channels between catalyst plates, occur in a highly non-isothermal, developing laminar gas flow and in conditions of mixed convection. A kinetic model of heterogeneous catalysis was implemented into the model and the heat radiation from the catalyst surface was accounted for. The model with no adjustable parameters was verified against experimental results available in literature and results of numerical simulations obtained by CFD methods.
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Sousa, Gustavo Gomes de y José Roberto dos Santos Politi. "ASPECTOS ENERGÉTICOS E ELETRÔNICOS DA ZEÓLITA H-ZSM-5 NA AÇÃO CATALÍTICA DA REAÇÃO DE DESIDRATAÇÃO DE ÁLCOOIS". En VIII Simpósio de Estrutura Eletrônica e Dinâmica Molecular. Universidade de Brasília, 2020. http://dx.doi.org/10.21826/viiiseedmol202087.

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Due to the growth of ecological concerns and the need to reduce dependence on fossil fuels, the dehydration of alcohols by acid catalysis has been used for the production of various hydrocarbons. Inside this theme, the H-ZSM-5 zeolite has been widely used as a catalyst for this reaction because its high efficiency. Thus, in order to understand the catalyzed reaction mechanism of the alcohol dehydration reaction, this work used the computational methodology ONIOM to study the catalytic behavior of the H-ZSM-5. It was modeled the dehydration reaction process for several alcohols (ethanol, propanol, isopropanol, butanol and 2-butanol) by modeling these alcohols within the zeolite cavity. The study was divided into 3 stages: the adsorption and protonation of alcohols by zeolite, the description of the hydroxyl outlet, and the formation of the double bond. The analysis of the results indicates that the first stage of the reaction occurs with the contact of alcohol with the zeolite cavity, where acid hydrogen promotes the protonation of alcohols, occurring differently for each alcohol. The dehydration process occurs, preferably, via E2 type elimination mechanisms. However, the profile of the energy curves indicates that for larger alcohols, the mechanism is intermediate between the elimination mechanisms E2 with some features of E1 (E2[E1]). Therefore, the zeolite converts alcohols to hydrocarbons in a specific way. Primary, lower-chain alcohols follow E2 mechanism, while secondary and longer-chain alcohols react by a slightly different mechanism, namely E2[E1].
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Abdul, Quiyoom, Pranab Kumar Rakshit, Ravi Kumar Voolapalli, Prince George, Dileep Kumar VN y Raviteja Thota. "Erosion Prediction in FCC Unit of Refinery Through Computational Fluid Dynamics Simulation". En ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211280-ms.

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Abstract In the Fluid Catalytic Cracking unit of refinery, erosion due to catalyst impact on wall refractories is a serious issue that affects the plant performance. In the present study, Computational Fluid Dynamics (CFD) coupled with Discrete Element Model (DEM) method is used to characterize gas-solid flow dynamics and erosion in regenerated catalyst slide pipe (RCSP). Catalyst particles size in the range of 1-180 µm were considered for the simulations. The predicted erosion profile was verified by comparing with thermography experiments and were found in a good agreement. The predicted results revealed that due to partial opening and orientation of regenerated catalyst slide valve, the rapid alterations of flow direction of catalyst particles take place. Particles recirculate in the rear end of the pipe and continuously impinges at the 12 o'clock position upstream of the valve. This led to erosion in the pipe. The experimentally validated CFD model was used to characterize the erosion profile under different relative openings of regenerated catalyst slide valve (RSCV). It was observed that with increasing the valve opening the erosion profile was reduced due to decreases catalyst recirculation velocity and vice-versa. Further, effect of valve opening orientation was also studied and it was found that by changing the valve opening orientation from parallel to ground surface to down towards, erosion was not observed due to small recirculatory flow of catalyst with low velocity. The results presented in this work will help refiners to understand the catalyst flow dynamics inside the regenerated catalyst slide pipe, root cause of erosion in pipes, and to achieve further improvements in the performance of plant.
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Varfolomeev, Mikhail Alekseevich, Chengdong Yuan, Alexander Vladimirovich Bolotov, Emil Rinatovich Saifullin, Ilgiz Failevich Minkhanov, Seyedsaeed Mehrabi-Kalajahi, Vadim Konstantinovich Derevyanko et al. "Case Study on the Application of In-Situ Combustion for Ultra-Low Permeability Oil Shale from Natih B Formation (Oman): Synthetic Oil Generation and Micro-Scale Pore Structure Changes". En ADIPEC. SPE, 2022. http://dx.doi.org/10.2118/211011-ms.

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Abstract Oil shale is considered as the world's second largest solid fossil fuel resource. Oil shale is an extremely ash-rich sedimentary rock loaded with organic matter. Most of the organic matter is rich in kerogen and a small amount of bitumen, which can be converted into synthetic oil using different thermal treatment methods. In-situ combustion (ISC) is a promising thermal enhanced oil recovery (EOR) method for the conversion of kerogen contained in oil shale to synthetic oil by oxidation. However, its field application is still limited due to difficulty in ignition, low combustion efficiency, and low rock permeability, etc. The main goal of this work was to determine the optimal conditions for synthetic oil generation and changes in the properties of oil shale. In this work, a self-designed combustion tube was developed to evaluate the effect of catalyst and water, including improving combustion front propagation and shale oil recovery. Copper (II) stearate (0.1 wt% by metal) was used as an oil-soluble catalyst to improve the process of ISC. The performance of ISC was evaluated in terms of material balance, recovery factor, composition of evolved gases, and produced synthetic oil quality. In addition, the changes in the properties of oil shale rock were also investigated using 3D computed tomography. According to the results of the combustion tube experiments, the presence of both water and catalysts is favorable for reactions that produce synthetic oil, sufficient heat generation (according to CO2 release) and hydrocarbon gases. The temperature profile and pressure profile indicate a successful ignition and successful establishment of combustion front for Natih B oil shale. The catalysts and water together improved the stability of combustion front and increase the efficiency of ISC process. The permeability was increased about 4 times higher after combustion. Generally, these promising results technically prove the potential for the development of shale oil from Natih B Formation (Oman) by ISC process. The use of ISC can allow the conversion of oil shale into light synthetic oil with hydrocarbon gas production. Moreover, based on the obtained results the in-situ combustion can occur in ultra-low permeability reservoirs.
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Cheong, H. T., Z. Siri y S. Sivasankaran. "Natural convection in an inclined square enclosure subject to sinusoidal temperature profile". En PROCEEDINGS OF THE 20TH NATIONAL SYMPOSIUM ON MATHEMATICAL SCIENCES: Research in Mathematical Sciences: A Catalyst for Creativity and Innovation. AIP, 2013. http://dx.doi.org/10.1063/1.4801106.

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Maeda, Tsuyoshi, Toshio Shinoki, Jiro Funaki y Katsuya Hirata. "Hydrogen Production by Bio-Fuel Steam Reforming at Low Reaction Temperature". En ASME 2011 Power Conference collocated with JSME ICOPE 2011. ASMEDC, 2011. http://dx.doi.org/10.1115/power2011-55383.

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The authors reveal the dominant chemical reactions and the optimum conditions, supposing the design of ethanol steam-reforming reactors. Specifically speaking, experiments are conducted for Cu/ZnO/Al2O3 catalyst, together with those for Ru/Al2O3 catalyst for reference. Using a household-use-scale reactor with well-controlled temperature distributions, the authors compare experimental results with chemical-equilibrium theories. It has revealed by Shinoki et al. (2011) that the Cu/ZnO/Al2O3 catalyst shows rather high performance with high hydrogen concentration CH2 at low values of reaction temperature TR. Because, the Cu/ZnO/Al2O3 catalyst promotes the ethanol-steam-reforming and water-gas-shift reactions, but does not promote the methanation reaction. So, in the present study, the authors reveal that the Ru/Al2O3 catalyst needs high TR > 770 K for better performance than the Cu/ZnO/Al2O3 catalyst, and that the Ru/Al2O3 catalyst shows lower performance at TR < 770 K. Then, the Ru/Al2O3 catalyst is considered to activate all the three reactions even at low TR. Furthermore, concerning the Cu/ZnO/Al2O3 catalyst, the authors reveal the influences of liquid-hourly space velocity LHSV upon concentrations such as CH2, CCO2, CCO and CCH4 and the influence of LHSV upon the ethanol conversion XC2H5OH, in a range of LHSV from 0.05 h−1 to 0.8 h−1, at S/C = 3.0 and TR = 520 K. And, the authors reveal the influences of the thermal profile upon CH2, CCO2, CCO, CCH4 and XC2H5OH, for several LHSV’s. To conclude, with well-controlled temperatures, the reformed gas can be close to the theory. In addition, the authors investigate the influences of S/C.
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7

Ramadan, Bassem H. y Russel L. Richmond. "A Three-Dimensional Transient Numerical Study of a Close-Coupled Catalytic Converter Internal Flow". En ASME/JSME 2007 5th Joint Fluids Engineering Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/fedsm2007-37635.

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This study involves a numerical and experimental investigation of fluid flow in automotive catalytic converters. The numerical work involves using computational fluid dynamics (CFD) to perform three-dimensional calculations of turbulent flow in an inlet pipe, inlet cone, catalyst substrate (porous medium), outlet cone, and outlet pipe. The experimental work includes using hot-wire anemometry to measure the velocity profile at the outlet of the catalyst substrate, and pressure drop measurements across the system. Very often, the designer may have to resort to offset inlet and outlet cones, or angled inlet pipes due to space limitations. Hence, it is very difficult to achieve a good flow distribution at the inlet cross section of the catalyst substrate. Therefore, it is important to study the effect of the geometry of the catalytic converter on flow uniformity in the substrate. The analysis involved determining back pressure (BP) across the converter system for different monolith cell densities, mass flow rates, converter aspect ratio, inlet cone angle, and inlet pipe offset. The numerical results were used to study the velocity profile at the inlet to the substrate, and were verified with experimental measurements of velocity and BP.
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8

Dobson, Peter y Marc Secanell. "The Effect of Ionomer Thin Films in Ionomer- and Water-Filled Agglomerate Models". En ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology collocated with ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/fuelcell2011-54259.

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The catalyst layer of a polymer electrolyte fuel cell is commonly represented in mathematical models as an agglomerate structure of carbon catalyst-support particles. There are two prevailing assumptions for the structure of the agglomerates. The first is that the pores are filled with perfluorosulfonated-ionomer (PFSI). The second is that the pores are hydrophilic and are flooded only with liquid water during operation. The objective of this work is to develop numerical models for single water-filled and ionomer-filled agglomerates in a cathode catalyst layer of a polymer electrolyte membrane fuel cell (PEMFC), and investigate the properties of oxygen transport, proton transport, and reaction kinetics. The two models provide different solutions for the distribution of oxygen and protons, and produce a different reaction profile within the agglomerate. Previous numerical water-filled ionomer models in the literature have neglected the effect of the ionomer thin film. Therefore, the results obtained for both ionomer and water-filled models could not be easily compared. In this article, the equations developed relate the assumed structure of the agglomerates to the structure of the catalyst layer (CL). Results compare the effect of the thin film thickness in the two different types of agglomerates and relate the phenomena occurring within the agglomerates to overall catalyst layer performance.
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9

Xu, Yousheng, Pengtao Sun, Hui He y Yang Liu. "Lattice Boltzmann Simulation of Solid Oxide Fuel Cell Performance". En ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology collocated with ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/fuelcell2011-54927.

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Based on models of a porous electrode, a more accurate lattice Boltzmann model for simulating the performance of a solid oxide fuel cell (SOFC) is proposed. The fuel is pure Carbon monoxide and the flow in the SOFC is steady. Results show good agreement between simulated and measured data. The accuracy of concentration overpotential prediction is crucial for low reactant concentrations. The addition of a small amount of air to the fuel yields fully stable performance without measurable carbon deposits detected on the catalyst layer or the fuel cell. Cell performance increases with the temperature. As a first test of the model, a benchmark problem regarding the performance of an internal reforming solid oxide fuel cell (IR-SOFC) is investigated. When the catalyst activity decreases, the rate of methane conversion decreases near the reactor entrance and thus the temperature profile is smoother. This phenomenon is termed methane slippage.
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10

Storey, J. M., S. A. Lewis, T. Dam, K. W. Kahl y T. J. Theiss. "Regulated and Unregulated Emissions From a Stoichiometric 250kW Natural Gas Engine". En ASME 2004 Internal Combustion Engine Division Fall Technical Conference. ASMEDC, 2004. http://dx.doi.org/10.1115/icef2004-0978.

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The emissions profile from a natural gas (NG) stationary power, stoichiometric, engine have been measured. Of particular interest are the unregulated emissions (especially formaldehyde) from this engine class. A relatively small 250 kW Caterpillar G3406 engine without a catalyst was used as the test platform with the emissions being characterized as a function of applied load and external conditions. In addition, multiple formaldehyde measurement techniques have been used and are compared. This paper presents the formaldehyde results, comparison of formaldehyde with various other parameters, a comparison of the different measurement techniques, and measurement of other toxic emissions from this engine.
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Informes sobre el tema "Catalyse profane"

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Morkun, Volodymyr S., Сергій Олексійович Семеріков y Svitlana M. Hryshchenko. Use of the system Moodle in the formation of ecological competence of future engineers with the use of geoinformation technologies. Видавництво “CSITA”, 2016. http://dx.doi.org/10.31812/0564/718.

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At present the information and communication technologies in education can be a catalyst in solving important social problems connected with increasing the educational resources and services availability and quality, real and equal opportunities in getting education for citizens despite their residence, social status and income. One of the most important education tasks is to develop students’ active cognitive attitude to knowledge. Cognitive activity in universities is a necessary stage in preparing for further professional life. The solution of task of formation of ecological competence of mining profile engineer requires the reasonable selection of the means of information and communication technologies conducing formation of ecological competence. Pressing task is constructive and research approach to preparation of future engineers to performance of professional duties in order to make them capable to develop engineering projects independently and exercise control competently. The relevance of the material covered in the article, due to the need to ensure the effectiveness of the educational process in the preparation of the future Mining Engineers. We analyze the source with problems of formation of ecological competence. The article focuses mainly general-purpose computer system support learning Moodle, which allows you to organize individual and collective work of students to master the specialized course teaching material used in teaching special course "Environmental Geoinformatics" in the implementation of educational research.
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