Literatura académica sobre el tema "Lay catalysis"
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Artículos de revistas sobre el tema "Lay catalysis"
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Zhang, Lian Zi y Hao Yuan Sun. "Development of Catalysts for Synthesizing Methanol from Syngas". Materials Science Forum 1053 (17 de febrero de 2022): 165–69. http://dx.doi.org/10.4028/p-0eor9r.
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At present, methanol is one of the most basic organic chemical raw materials and energy storage media. With the development of chemical technology and energy storage technology, its application becomes more and more extensive, and the methanol market prospects are unlimited. Industrial-scale methanol is generally prepared by using synthesis gas containing hydrogen, carbon monoxide, and carbon dioxide as raw materials and reacting under a certain pressure, temperature, and catalyst. Therefore, the development of the methanol industry largely depends on the development of catalysts and the improvement of their performance. Metal catalysts are mainly used in the industry for reaction. This article reviews several metal catalysts used to synthesize methanol from syngas. Copper-based and iron-based catalysts are widely used, and the emerging rhodium and its ligand catalysts exhibit good catalytic performance in low-temperature catalysis. In the future, the scientific research team will focus on in-depth research on preparation methods, active centers, catalytic reaction kinetics, durability, metal ligands, raw material prices, etc., to lay a solid foundation for the industrial application of syngas to methanol in advance.
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Poier, Dario, Sharon Mitchell, Victor Tulus, Gonzalo Guillén-Gosálbez, Javier Pérez-Ramírez y Roger Marti. "Aiming for More Sustainable Cross-Coupling Chemistry by Employing Single-Atom Catalysis on Scale". CHIMIA 77, n.º 3 (29 de marzo de 2023): 127. http://dx.doi.org/10.2533/chimia.2023.127.
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Scaling up syntheses from mg to kg quantities is a complex endeavor. Besides adapting laboratory protocols to industrial processes and equipment and thorough safety assessments, much attention is paid to the reduction of the process’ environmental impact. For processes including transition metal catalyzed steps, e.g. cross-coupling chemistry, this impact strongly depends on the identity of the metal used. As such, a key approach is the replacement of single-use with reusable heterogeneous catalysts. Transition metal single-atom heterogeneous catalysts (SAC), a novel class of catalytic materials, might exhibit all the necessary properties to step up to this task. This article shall discuss current applications of SAC in cross-coupling chemistry from the point of a process chemist and shed light on the NCCR Catalysis contribution to the field. Investigations of the stability-activity-selectivity relationship of SACs in combination with early-stage life-cycle assessments (LCA) of potential processes lay the foundation for large-scale application tailored catalyst synthesis. Ultimately, prevailing challenges are highlighted, which need to be addressed in future research.
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García, Pablo, Enrique Lima, Julia Aguilar y Víctor Lara. "Fractal Extra-Framework Species in De-aluminated LaY Zeolites and Their Catalytic Activity". Catalysis Letters 128, n.º 3-4 (18 de noviembre de 2008): 385–91. http://dx.doi.org/10.1007/s10562-008-9761-5.
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Zhang, Qian, Qiyu Peng, Wenbin Li, Yanzhang Liu y Xiaoxiong Wang. "Waste Plastic Recycling Upgrade Design Nanogenerator for Catalytic Degradation of Pollutants". Catalysts 13, n.º 6 (19 de junio de 2023): 1019. http://dx.doi.org/10.3390/catal13061019.
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In recent years, electrocatalytic degradation of pollutants based on nanogenerators has gradually emerged. Compared with the huge energy consumption of traditional electrocatalysis, this method can effectively use displacement current to induce charge transfer and complete catalysis, so it can directly use the existing water flow energy and other energy sources in nature. This work will explain the basic principles, methods, and measurement methods of preparing nanogenerators from waste plastics, as well as the classification of electrocatalytic principles and methods relative to nanogenerators, which provides important support for the research in this emerging field. At the same time, the analysis based on this knowledge will also lay the foundation for future design.
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Xu, Jiayi, Jinkui Pi, Yanjing Zhang, Jinhan Zhou, Shuxia Zhang y Sisi Wu. "Effects of Ferroptosis on Cardiovascular Diseases". Mediators of Inflammation 2023 (4 de mayo de 2023): 1–11. http://dx.doi.org/10.1155/2023/6653202.
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Ferroptosis is a novel form of programmed cell death characterized by the accumulation of iron-dependent lipid peroxides, which causes membrane injury. Under the catalysis of iron ions, cells deficient in glutathione peroxidase (GPX4) cannot preserve the balance in lipid oxidative metabolism, and the buildup of reactive oxygen species on the membrane lipids leads to cell death. An increasing body of evidence suggests that ferroptosis plays a significant role in the development and occurrence of cardiovascular diseases. In this paper, we mainly elaborated on the molecular mechanisms regulating ferroptosis and its impact on cardiovascular disease to lay the groundwork for future studies on the prophylaxis and treatment of this patient population.
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Bowker, M. "The effect of coke lay-down on n-heptane reforming on Pt and Pt-Sn catalysts". Applied Catalysis A: General 257, n.º 1 (10 de enero de 2004): 57–65. http://dx.doi.org/10.1016/s0926-860x(03)00613-6.
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Hoyle, Jeffrey, J. Stuart Grossert, Donald L. Hooper y Subramanian Sotheeswaran. "Sulphur-33 nuclear magnetic resonance spectroscopy of sulphones". Canadian Journal of Chemistry 64, n.º 8 (1 de agosto de 1986): 1581–84. http://dx.doi.org/10.1139/v86-261.
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The sulphur-33 nmr spectra of 28 sulphones were measured in deuterochloroform solutions at 27.716172 MHz. The spectra were referenced with respect to an external aqueous ammonium sulphate solution and the chemical shifts lay in the range 0 ± 20 ppm, with many lines having a half-height width of less than 200 Hz. Instrumental parameters that affect the spectra were studied. Some of the sulphur-33 resonances can be correlated well with carbon-13 or oxygen-17 resonances in appropriate analogous compounds, and with the Taft σ* parameter.
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Aloni, Sapir Shekef, Molhm Nassir y Yitzhak Mastai. "Chiral Porous Carbon Surfaces for Enantiospecific Synthesis". Polymers 14, n.º 14 (6 de julio de 2022): 2765. http://dx.doi.org/10.3390/polym14142765.
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Chiral surfaces, developed in the last decade, serve as media for enantioselective chemical reactions. Until today, they have been based mostly on developments in silica templating, and are made mainly from imprints of silicate materials developed a long time ago. Here, a chiral porous activated carbon surface was developed based on a chiral ionic liquid, and the surface chemistry and pore structure were studied to lay a new course of action in the field. The enantioselectivities of surfaces are examined by using variety of methods such as circular dichroism, linear sweep voltammetry and catalysis. These techniques revealed a 28.1% preference for the D enantiomer of the amino acid proline, and linear sweep voltammetry confirmed chirality recognition by another probe. An aldol surface chiral catalytic reaction was devised and allowed to determine the root of the enantiomeric excess. These results affirm the path toward a new type of chiral surface.
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Cong, Fangdi, Hongzhen Jiang, Xiguang Du, Shulin Zhang y Wei Yang. "Facile, Mild-Temperature Synthesis of Metal-Free Phthalocyanines". Synthesis 53, n.º 15 (5 de mayo de 2021): 2656–64. http://dx.doi.org/10.1055/a-1499-8865.
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AbstractIt is important for the synthesis and research of phthalocyanine compounds for these compounds to be easily obtained at low temperature. We observed that metal-free phthalocyanine was sometimes found in a simple system used to synthesize phthalocyanine precursors at room temperature, and further studies showed that the key to the effective formation of phthalocyanines at low temperature lay in the presence of equal volumes of alcohol and amine, in addition to substrate phthalonitriles and solvents, in the reaction system. A synthetic mechanism was proposed and facile syntheses have been realized, such as the synthesis of tetra-α(β)-nitrophthalocyanines and tetra-α(β)-(4-tert-butylphenoxy)phthalocyanines from the corresponding substituted phthalonitriles at mild temperature (37 °C). The results are significant for the design and synthesis of new phthalocyanine derivatives, and the method is convenient and easy to adopt for general use in standard laboratories.
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Rizkin, Benjamin A. y Ryan L. Hartman. "Activation of homogenous polyolefin catalysis with a machine-assisted reactor laboratory-in-a-box (μAIR-LAB)". Reaction Chemistry & Engineering 5, n.º 8 (2020): 1450–60. http://dx.doi.org/10.1039/d0re00139b.
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Catalysis discovery is typically limited to specialized labs – this work demonstrates an Artificially Intelligent Microreactor Lab in a Box applied to investigate the chemistry of different co-catalysts for zirconocene-catalyzed olefin polymerization.
Tesis sobre el tema "Lay catalysis"
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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 déterminantIs 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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Law, Cameron Hunter. "Investigation of chemical anchoring of nickel catalyst networks by aluminum titanate additives". Thesis, Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/law/LawC0811.pdf.
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Electrocatalysts are incorporated into a plethora of technologies and material systems such as catalytic converters, reforming systems, multilayer ceramic capacitors, and solid oxide fuel cells (SOFCs). In SOFCs, nickel is commonly the catalyst of choice due to its chemical stability, high catalytic activity, and lower cost. While traditional SOFCs have a bulk mixture of nickel and yttria stabilized zirconia (YSZ) with at least 33 vol% nickel, solution infiltrated anode SOFCs have several benefits including lower nickel vol% to satisfy percolation, better mechanical strength and CTE matching that can improve redox cycling. Coarsening of the fine nickel metal catalyst with microstructures below 1 micrometer have shown a strong propensity to coarsen from thermal migration at temperatures above 700°C. This migration induced degradation by decreasing particle surface area and nickel network connectivity for electrical conduction. Utilizing metastable oxide additives as a minor dopant in the anode cermet system, novel methods of anchoring the metal phase to porous YSZ ceramic scaffolds have been identified as a means to engineer infiltrated anodes for improved performance. Less than 10 wt% aluminum titanate (ALT-Al ₂TiO ₅), added to YSZ by mechanical mixing, has shown a stepwise process in the formation of NiAl ₂O ₄ at 1100°C and ZrTiO ₄ at 1205°C for chemically binding the nickel phase to YSZ. XRD, SEM, TEM, and EDS characterization coupled with FIB sample preparation has been utilized to identify the size, morphology, composition and temperature at which the anchoring phases form. Area specific resistance tests of component anodes indicate a decrease in degradation of at least 521%/1000 hr compared to infiltrated specimens without the ALT additive. Electrochemical tests of electrolyte supported cells (ESC) show higher initial performance of cells doped with ALT and at least a 1400%/1000 hr reduction in performance degradation at the same nickel loading content.
'Co-authored by Stephen W. Sofie, Zane Townsend and Max Lifson.'
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Lantto, Cornelia. "Sulfur tolerance of SCR catalysts : Development of a lab testing method". Thesis, Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-64201.
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NOx emissions from diesel vehicles are a currently well-discussed matter due to the related health and environmental issues. At the same time, diesel vehicles are an important part of transportation in society as diesel engines are more fuel efficient than gasoline engines. NOx emissions are regulated by European standards, this put demands on a well-functioning exhaust gas aftertreatment system that lower the NOx emissions for the whole lifetime of the vehicle. One of the most effective solutions is by reduction of NOx with ammonia over a SCR catalyst. Cu/SSZ-13 zeolite has shown to be a promising SCR catalyst. SCR catalysts are however deactivated by several different mechanisms, where sulfur poisoning is a significant mechanism. There are many different factors that will influence how sulfur impacts the catalyst. Different catalyst materials are more or less sulfur tolerant. The form of sulfur is important as well as both temperature and availability of ammonia. It is thus important to investigate how sulfur affects the SCR catalyst. The aim of this master’s thesis project was to develop a method for measuring sulfur tolerance of different SCR catalysts and to gain understanding of sulfur poisoning of Cu/SSZ-13 catalysts. A literature study on sulfur poisoning of SCR catalysts with a focus on Cu/SSZ-13 was first carried out. Followed by an experimental part in a rig at Scania CV AB in Södertälje, where the method was developed. A method that can be used for testing SCR catalysts on sulfur tolerance after SO2 exposure was successfully achieved. The experimental procedure was designed to consist of eight steps, including de-greening, sulfur poisoning, regeneration at two temperatures and catalyst activity test after each step. Clear differences on NOx conversion between fresh, sulfated and regenerated catalysts are observed when using the method. Three different sulfation temperatures were evaluated where the lower sulfation temperatures, 220 ⁰C and 280 ⁰C, caused a larger impact on NOx conversion compared to sulfation at 350 ⁰C. Two different catalysts were compared on their NOx conversion over fresh, sulfated and regenerated catalysts. The method was correlated to engine aging with respect to sulfur exposure, sulfur capture, gas and temperature conditions and activity loss. The method corresponds to approximately 430 000 km driving based on sulfur exposure over the catalyst. The lab method is best comparable to a SCR catalyst located first in the exhaust gas aftertreatment system in a vehicle, based on two conclusions. (1) Poisoning is performed with only SO2. (2) Standard SCR conditions occur in the activity test. The method should be further developed by enabling testing of NOx conversion at fast and slow SCR conditions. More work should be carried out on the correlation to vehicle aging by comparision with engine aged catalysts.
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Gotteland, Delphine. "Procédé d’hydroconversion par catalyse dispersée des résidus lourds pétroliers". Thesis, Lyon 1, 2011. http://www.theses.fr/2011LYO10198.
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Guilnaz, Mirmoshtaghi Seyedeh. "Simulation of a lab-scale methanation reactor". Thesis, KTH, Kemiteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-90395.
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By the everyday increasing enthusiasm for using renewable-sustainable sources in energy production area, focusing on one and optimizing it in the best possible way should be of much interest. Biogas production from anaerobic digestion of wastes is a well known energy source which could be applied more efficiently if the CO2portion of it would be upgraded to CH4as well. There is a methanation reaction which could convert carbon dioxide to methane with the use of hydrogenation. In this report, the effort is to simulate this methanation reactor which is a catalytic bed of ruthenium on alumina base. The temperature change and its’ effect on reaction kinetics and equilibrium, also deriving designing parameters for the catalyst bed are different tasks which was tried to be covered in this thesis work. Based on calculations, the reactor can operate isothermally or adiabatically. The point is that each method has its own cons and pros. For the isothermal case finally the optimum temperature to run the reaction is decided to be 600 K in 10 bar total pressure. In adiabatic case then it is understood to work on interstage cooling strategy which in given conditions came to the number of 6 for reactors and 5 for interstage cooling devices. Afterwards it is thought to apply some technical changes to conventional adiabatic method and recycle some part of the product to the entrance of the reactor and assist the conversion. In this method number of reactors would be reduced to 2 and one heat exchanger in the middle. Selecting the best process in large scale treatment, needs lots of economical analysis and detail design while in small scale condition the most preferred method to run the reaction is isothermal.
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Boulens, Pierre. "Sulphonamido-phosphorus nickel complexes for the selective oligomerisation of olefins - Exploring dissymmetric ligands and supramolecular strategies". Thesis, Lyon, École normale supérieure, 2014. http://www.theses.fr/2014ENSL0973/document.
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Les alpha oléfines linéaires courtes sont des molécules de base en pétrochimie donc le marché est en constante augmentation notamment pour les oléfines légères (butène-1, hexène-1, octène-1). Ces oléfines, utilisées massivement dans l’industrie des plastiques, sont produites par la réaction catalytique d’oligomerisation de l’éthylène. IFPEN a contribué à développer plusieurs procédés homogènes d’oligomérisation de l’éthylène (AlphaButol, AlphaHexol, AlphaSelect) à base des complexes de titane, chrome ou zirconium. A travers une collaboration avec l’Université d’Amsterdam de nouvelles stratégies de développement de ligands ont été entreprises afin de rendre les catalyseurs à base de nickel sélectifs pour cette transformation. Ainsi, une approche supramoléculaire basée sur des interactions par liaison hydrogène, jusqu’alors décrite pour les métaux nobles, a été développée et appliquée aux complexes de nickel. Des complexes organométalliques originaux ont pu être générés et les interactions supramoléculaires ont été caractérisées par diffraction aux rayons X notamment. Ces complexes se présentent sous forme zwitterionique et sont formés par la combinaison de deux ligands simples donneurs et/ou accepteurs d’hydrogène. Ces complexes se sont avérés très actifs vis-à-vis de l’éthylène et ne nécessite pas l’ajout d’activateur du fait de la présence d’une liaison nickel-carbone réactive. Ils ont permis d’accéder à des sélectivités très importantes en butène-1. Appuyé par des expériences in situ et l’évaluation en catalyse de plusieurs complexes aux propriétés électroniques et stériques variées, cette approche a permis d’identifier l’espèce active et de mesurer l’impact de plusieurs descripteurs permettant de moduler la sélectivité et l’activité de la réaction catalytique en profondeurThe demand for short linear alpha olefins is constantly increasing and motivates the development of robust and selective catalysts. In this thesis, several libraries of phosphorus ligands with the capacity to form dissymmetric or supramolecular assemblies were synthesized. The variability observed within the aminophosphine libraries, clearly reflected by the various tautomeric equilibrium of the ligand, was also observed in the nickel complexes as a single ligand could generate several complexes with different structures. Sulphonyliminobisphosphine were then introduced as a new class of ligands. These precursors rearrange in the presence of nickel to generate diphosphinamine nickel complexes. Activated by MAO, these complexes are active in the reaction of ethylene oligomerisation and produce short chain olefins. A new approach that forms stable supramolecular nickel complexes was developed by combining two phosphorus ligands with Ni(0). These complexes stabilised by hydrogen bonding are directly active in the reaction of ethylene oligomerisation with some catalysts leading to high selectivity to 1-butene (up to 84%). To understand the origin of that selectivity, the scope of complexes was extended to ligands with different steric and electronic properties. Their evaluation in the reaction of ethylene oligomerisation evidenced a relation between the catalyst structure and the selectivity of the reaction. Mechanistic studies, under an ethylene atmosphere, reveals that cationic complexes rearrange to neutral complexes, which are likely, the active species
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Marchand, Paul R. "The export development corporation : catalyst in Canada's promotion of international trade". Thesis, McGill University, 1985. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=64491.
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Payne, Bridget Áine. "State-Financed Merger and Acquisition Activity in Germany as a Catalyst for Robust Chinese Patent Law Enforcement". Scholarship @ Claremont, 2018. http://scholarship.claremont.edu/scripps_theses/1171.
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Germany’s economic dominance in Europe, generous investment incentives, and technical manufacturing prowess has encouraged an influx of Chinese-led inbound activity, concentrated in high-tech sector mergers and acquisitions. A close examination of these M&As yields evidence of systemic Chinese state-financing through both state-owned and private vehicles that likely stems from China’s “Made in China 2025” policy, which hopes to stem capital outflow and to indigenize technological innovation. As Germany braces for what it sees to be continuous attempts by China to take patented German technology through M&As, it worries that Chinese patent law will allow for rampant patent infringement by copycat Chinese entities.
This paper presents an overview of the root causes of China’s heavy economic activity in Germany, as well as an analysis of the legal concerns held by German firms based on a close reading of the Patent Law of the People’s Republic of China and strategic recommendations for German companies hoping to work with or in China.
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Vlachos, Chris Alex. "Law and sin an Edenic nexus? : a study with reference to 1 Corinthians 15:56 and the catalytic operation of the law /". Theological Research Exchange Network (TREN), 2006. http://www.tren.com/search.cfm?p088-0157.
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Martin, Derrick W. A. "From the Desire to Mark Essex: The Catalysts of Militarization for the New Orleans Police Department". ScholarWorks@UNO, 2016. http://scholarworks.uno.edu/td/2174.
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Abstract
The ultimate goal in the South was to end segregation, but nationwide equal-rights were the common goal of all African-Americans. Nonviolent protests and over aggressive police departments became the norm within the African-American community. Understated in the history of the Civil Rights Era is the role of armed resistance and Black Nationalism. Marcus Garvey, Stokely Carmichael, Huey P. Newton, and Malcolm X were Black Nationalists that led the charge of Black Nationalism worldwide. The Deacons of Defense, the Lowndes County Freedom Organization (LCFO) and the Black Panther Party for Self Defense transformed the social makeup of the country and became major causes of the militarization of police departments across the United States. Many police departments across America began to create SWAT teams and use military-style weaponry following an outbreak of riots and the assassination of Dr. Martin Luther King Jr. In New Orleans, Louisiana, stand-offs and shoot-outs with Black Panther members warranted a call for military backup, but it was the acts of Mark James Robert Essex that totally militarized the New Orleans Police Department.
Libros sobre el tema "Lay catalysis"
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Gonzales, Benedicto M. Local legislation and governance: Catalysts of national development. Quezon City, Philippines: Central Book Supply, Inc., 2013.
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Gonzales, Benedicto M. Local legislation and governance: Catalysts of national development. Quezon City, Philippines: Central Print on Demand, 2006.
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Hayes, R. E. Introduction to catalytic combustion. Amsterdam, The Netherlands: Gordon and Breach, 1997.
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Affirmative action: Catalyst or albatross? Commack, N.Y: Nova Science Publishers, 1998.
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Conning & Company. Risk-based capital for life insurers: Catalyst for change. Hartford, CT (185 Asylum St., Hartford 06103-4105): Conning & Company, 1993.
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Lehman, John W. Catalyst: The Prentice Hall custom laboratory program for chemistry : Columbia University, Organic chemistry lab manual. Boston: Pearson Learning Solutions, 2010.
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The catalysts of life processes: An inaugural lecture delivered at the University of Lagos on Wednesday, 23rd October, 1991. Lagos: University of Lagos Press, 1992.
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Holzinger, Katharina. Politik des kleinsten gemeinsamen Nenners?: Umweltpoltitische Entscheidungsprozesse in der EG am Beispiel der Einführung des Katalysatorautos. Berlin: Edition Sigma, 1994.
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Jaffer, Sohail. Islamic wealth management: A catalyst for global change and innovation. London: Euromoney Books, 2009.
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Democratization and market reform in developing and transitional countries: Think tanks as catalysts. London: Routledge, 2010.
Buscar texto completoCapítulos de libros sobre el tema "Lay catalysis"
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Xu, Feng. "Organocatalysis for Asymmetric Synthesis: From Lab To Factory". En Sustainable Catalysis, 317–37. Hoboken, New Jersey: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118354520.ch14.
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Leffler, Phyllis. "Law and Social Change: Catalyst for Leadership". En Black Leaders on Leadership, 137–66. New York: Palgrave Macmillan US, 2014. http://dx.doi.org/10.1057/9781137342515_6.
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Ioriatti, Elena. "Comparative Law Method and Legal Formants as Catalysts of Normative Realities". En The Grand Strategy of Comparative Law, 39–54. London: Routledge, 2024. http://dx.doi.org/10.4324/9781003371946-20.
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Kawai, Masahiro y Henrik Schmiegelow. "Financial Crisis as a Catalyst of Legal Reforms: The Case of Asia". En Institutional Competition between Common Law and Civil Law, 381–420. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-54660-0_15.
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Eskelinen, Pia. "Rural Women’s Land Use Rights in China: Acceptance and Enforceability". En Towards Gender Equality in Law, 111–32. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-98072-6_6.
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AbstractLegal control of land as well as legal and social recognition of women’s uses of and rights to land can have catalytic effects of empowerment, increasing women’s influence and status in their communities. During past decades, changes in the Chinese land tenure rights and practices have brought important incentives for rural developments including farmer income and living standards. However, the law in books differs from the law in action and the lack of women’s land use rights recognition deprives them of their chances of surviving in rural China. They become legally invisible, ignored and forgotten. This qualitative research is mainly based on interviews conducted in China. The data will be analysed within the framework of theories and philosophies grounding Chinese ideology. As this research focus on women in rural areas, feminism form the theoretical and ideological background.
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Khong, Dennis W. K. y P. C. Lim. "The Power of Free as a Catalyst for Political Revolution". En Law and Economics in Europe and the U.S., 89–107. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-47471-7_6.
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Maskill, Howard. "Catalysis of organic reactions in solution by small molecules and ions". En Structure and Reactivity in Organic Chemistry. Oxford University Press, 1999. http://dx.doi.org/10.1093/hesc/9780198558200.003.0004.
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This chapter focuses on the catalysis of organic reactions in solution by small molecules and ions. Catalysis is the enhancement of the rate of a reaction by a compound (the catalyst) not generally present in the chemical equation which describes the reaction. Normally, a catalyst remains unchanged by the chemical reaction it catalyzes. It brings about the rate enhancement by providing a reaction pathway additional to the one which occurs in its absence. This additional pathway will have its own rate law, and the total rate of reaction in the presence of the catalyst is the sum of the catalysed and uncatalyzed pathways. The chapter then looks at electrophile catalysis, specific acid catalysis, general acid catalysis, nucleophile catalysis, specific base catalysis, and general base catalysis. It also considers the Brønsted equation.
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Weitkamp, J. y S. Ernst. "Comparison Of The Reactions Of Ethylcyclohexane And 2-Methylheptane On Pd/Lay Zeolite". En Catalysis by Acids and Bases, 419–26. Elsevier, 1985. http://dx.doi.org/10.1016/s0167-2991(09)60192-0.
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Maixner, S., C. Y. Chen, P. J. Grobet, P. A. Jacobs y J. Weitkamp. "Investigation of Carbonaceous Deposits on a LaY Zeolite Catalyst by CP/MAS-13C-NMR Spectroscopy". En Studies in Surface Science and Catalysis, 693–700. Elsevier, 1986. http://dx.doi.org/10.1016/s0167-2991(09)60936-8.
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Maugé, F., J. C. Courcelle, Ph Engelhard, P. Gallezot y J. Grosmangin. "Hydrothermal Aging of Cracking Catalysts-III. Effect of Vanadium on the Structure of LaY Zeolites". En Studies in Surface Science and Catalysis, 803–9. Elsevier, 1986. http://dx.doi.org/10.1016/s0167-2991(09)60950-2.
Texto completoActas de conferencias sobre el tema "Lay catalysis"
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Lou, Diming, Yajuan Chen, Yunhua Zhang, Peng Wan, Piqiang Tan, Zhiyuan Hu, Liang Fang y Tong Wang. "Study on Soot Oxidation Characteristics of Ce and La Modified Pt-Pd CDPF Catalysts". En WCX SAE World Congress Experience. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2023. http://dx.doi.org/10.4271/2023-01-0390.
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<div class="section abstract"><div class="htmlview paragraph">The catalyzed diesel particulate filter with Pt and Pd noble metals as the main loaded active components are widely used in the field of automobile engines, but the high cost makes it face huge challenges. Rare earth element doping can improve the soot oxidation performance of the catalyzed diesel particulate filter and provide a new way to reduce its cost. In this paper, thermogravimetric tests and chemical reaction kinetic calculations were used to explore the effect of Pt-Pd catalysts doped Ce, and La rare earth elements on the oxidation properties of soot. The results shown that, among Pt-Pd-5%Ce, Pt-Pd-5%La, and Pt-Pd-5%Ce-5%La catalysts, Pt-Pd-5%La catalyst has the highest soot conversion, the highest low-temperature oxidation speed, and the activation energy is the smallest. Compared with soot, this catalyst reduced <i>T<sub>10</sub></i> and <i>T<sub>20</sub></i> by 82% and 26%, respectively, meaning the catalytic activity of Pt-Pd-5%La catalyst was the best. With the decrease of catalyst/soot ratios, the soot conversion and oxidation speed of Pt-Pd and Pt-Pd-5%La catalysts decreased, and characteristic temperature increased. In both catalyst formulations, samples with catalyst/soot ratio of 5 showed the best catalytic activity, and the other samples with smaller catalyst/soot ratios showed less difference. The study revealed the influence of doping elements and catalyst/soot ratios on the oxidation characteristics and reaction kinetics of soot, which has a guiding significance for optimizing the doping scheme of rare earth elements and realizing the reduction of noble metals.</div></div>
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Le Gal, Jean-Hervé, Gérard Martin y Daniel Durand. "Development of a Dual Fuel Catalytic Combustor for a 2.3 MWe Gas Turbine". En ASME 1998 International Gas Turbine and Aeroengine Congress and Exhibition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/98-gt-294.
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Biomass derived fuels are an essential alternative for heat and energy production, in order to minimise environmental impact, since they make no net contribution to the increase of CO2 emissions into the atmosphere. In certain countries, biofuels are also interesting since they are available as waste products from the agricultural or forestry industry. Unfortunately, combustion of biofuels often results in high emissions levels of pollutants such as NOx, CO and unburned hydrocarbons. In gas turbines, catalytic combustion of biofuels has the potential to reduce emissions of these undesired species. The ULECAT project (Ultra Low Emissions CATalytic combustor) described in this paper is the first step of a program aiming at the development of an ultra-low emission gas turbine in the range of 1 to 5 MWe, able to run with both biomass-derived gases and liquid fuels. The objective of the project is to assess the feasibility of a dual fuel catalytic combustor. Combustor design issues are investigated at full and part load conditions. For the comparison of combustor configuration, modelling provides a useful help for catalytic section design, in particular for the estimation of catalytic activity and wall temperature which strongly influence catalyst life time. Catalyst development is one of the main topics of this project. It is mainly focused on high temperature catalyst durability and the reduction of NOx formation. This last point is of primary importance in biofuels combustion and certain catalysts have shown an important potential in reducing ammonia conversion into NOx in some operating conditions. Catalyst performances are evaluated at lab scale and also pilot scale in representative gas turbine combustor conditions with both Diesel fuel and biomass derived fuels.
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Polaert, Isabelle, Bachar Alrafei, Jose Delgado-Liriano y Alain Ledoux. "Synergetic effect of microwave plasma and catalysts in CO2 methanation". En Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9806.
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The reduction of CO2 concentration in our atmosphere consists in a big challenge for researchers, who are trying to explore novel technologies in order to transform CO2 into high added-value products. CO2 conversion into methane using microwave plasma (MWP) manifests as a very promising solution due to the ease of transport of methane and its storage. Microwave plasma represents a source of high-energy electrons, active ions and radicals that enhance or enable chemical reaction. It can be supplied by electricity generated from renewable resources. Then, MWP does not require any electrode to be generated and thus, the cost of those electrodes and of maintenance is reduced compared to glow discharge or DBD plasmas. MWP also can be generated over wide range of pressure (between 10 mbar-1bar). In addition, in the case of MWP, more electrons and active species are produced in comparison with other type of plasma[1–4]. MWP is a very suitable medium for this chemical reaction and leads to an efficient dissociation of CO2. The catalytic reduction of CO2 with H2 using MWP has been investigated in this work and the synergetic effects between the plasma and several catalysts were studied. First, the reaction was carried out without any catalysts and the effect of CO2/H2 ratio, total flow rate and input energy were evaluated. Then, a microwave generated plasma process was coupled with several Nickel catalysts that we prepared and characterized [5] in order to lead the reaction into methane formation. Multiple configurations were studied by changing the position of the catalyst bed. Obtained results were compared with conventional catalytic tests made with the same catalysts. It was found that the conversion of CO2 and energy efficiency increased using plasma assisted catalytic methanation of CO2 in comparison with conventional process. Operating conditions were studied in order to optimize methane production and energy efficiency of Plasma-catalytic process. References Qin, Y., G. Niu, X. Wang, D. Luo, Y. Duan, J. CO2 Util., 2018, 28, 283–291. De la Fuente, J.F., S.H. Moreno, A.I. Stankiewicz, G.D. Stefanidis, Int J Hydrogen Energy, 2016, 41, 21067–21077. Ashford, B., X. Tu, Curr Opin Green Sustain Chem, 2017, 3, 45–49. Vesel, A., M. Mozetic, A. Drenik, M. Balat-Pichelin, Chem Phys., 2011, 382, 127–131. Alrafei, B., I. Polaert, A. Ledoux, F. Azzolina-Jury, Catal. Today, Available online 12 March 2019, In Press, Accepted Manuscript. https://doi.org/10.1016/j.cattod.2019.03.026
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Arias, Rebekah. "Image Analysis for SWNT Growth on Shutter Sputtered Catalyst". En MME Undergraduate Research Symposium. Florida International University, 2022. http://dx.doi.org/10.25148/mmeurs.010568.
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Carbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed onCarbon Nanotubes (CNTs) have been used in remarkable ways since their discovery in 1991 by Sumio Iijima. Properties such as high thermal conductivity, good mechanical strength, and electrical conductivity are what make CNTs attractive. Some of their applications include water filtration, vehicles, energy storage, and now there is great potential in the biomedical field for CNTs as composites in tissue engineering, therapeutics carrier across the blood-brain barrier, cancer treatment, and much more. The issue that comes with Single-Walled Nanotubes (SWNTs) however is Ostwald ripening of catalyst and low CNT production. It is difficult to control gas parameters for hydrogen and argon and can be dangerous in a smaller lab, so acetylene without dilution gas is used. The method proposed here utilizes shutter sputtering of Iron on a th-SiO2/AlO substrate, followed by thermal chemical vapor deposition (CVD) for annealing. Shutter sputtering allows greater particle adhesion to the substrate due to wavelength and energy changes, allowing smaller catalysts to grow and a greater possibility of long SWNTs. We compare the effects of Ostwald ripening on catalysts formed on a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis. a Fe shutter sputtered substrate annealed at 730°C and another at 760°C, in order to identify the correlation between the size and distance of catalyst particles for SWNT growths through Atomic Force Microscopy (AFM) image analysis.
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Fassihi, M. R., R. G. Moore, P. Pereira Almao, S. A. Mehta, M. G. Ursenbach y D. G. Mallory. "New Insights on Catalysts-Supported in situ Upgrading of Heavy Oil During in situ Combustion Oil Recovery". En SPE Annual Technical Conference and Exhibition. SPE, 2023. http://dx.doi.org/10.2118/215092-ms.
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Abstract As part of GHG reduction initiatives, there have been many publications on CO2 capture, utilization, and storage (CCUS), reducing the carbon footprints in the oil and gas production, switching to renewable energies, and generating carbonless fuel (e.g., H2) via in situ processes. In situ upgrading of bitumen and heavy oils and converting them into low sulfur, low N2, and low asphaltene can help with both producing cleaner fuel as well as utilizing vast resources of energy that could otherwise be wasted due to extreme measures of no fossil fuel policies. Additionally, such processes could produce valuable products, enhanced shipping/pipelining, and less demanding downstream processing. Generating hydrogen could be another focus area for in situ upgrading. This paper provides new insights into the results of several combustion tube tests that were performed for Alberta Ingenuity Centre for In Situ Energy (AICISE) using different heavy oils with fresh supported catalyst. The catalysts were placed in the production end of the combustion tube so oil would pass over the catalyst bed before being produced. In practice, solid catalyst particles could be placed into the oil-bearing formation adjacent to the producing wellbore, ensuring that crude oil will flow over the catalysts during oil production. This paper utilizes many of the lab results that have never been published before. The objective is to understand whether using catalysts has merits in our future oil production activities under the current environmental restrictions. A commercial Ni/Mo catalyst was used in these tests. The results of these tests indicated at least temporary significant occurrence of reactions such as: hydroprocessing (HP), hydrotreating reactions, such as hydrocracking (HC), hydrodesulfurization (HDS), hydrodenitrogenation (HDN) and hydrodeoxygenation (HDO). We will discuss the impact of pressure, temperature, water injection and dispersed versus supported catalysts on the degree of oil upgrading. Also, the key parameters that could impact in situ hydrogen generation will be presented. Specifically, the role of reactions such as Aquathermolysis (AQ), thermal cracking (TC), water-gas shift reaction (WGS) and coke gasification (CG) will be discussed. Notice that the products of these reactions could undergo additional methanation reactions (ME) which could reduce the H2 concentration in the produced gas. Finally, methods of upscaling these results to the field conditions will be presented.
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E., Nyamdavaa, Uyanga E., Sevjidsuren G. y Altantsog P. "PEROVSKITE-TYPE La1-XCeXMnO3 AS CATALYSTS: SYNTHESIS AND CHARACTERIZATION". En НАНОМАТЕРИАЛЫ И ТЕХНОЛОГИИ. Buryat State University Publishing Department, 2016. http://dx.doi.org/10.18101/978-5-9793-0898-2-23-29.
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Ibrahim, Sonia. "3D Heritage as a catalyst for social participation in safeguarding cities in conflict. A Case study of Damascus in Syria". En HERITAGE2022 International Conference on Vernacular Heritage: Culture, People and Sustainability. Valencia: Universitat Politècnica de València, 2022. http://dx.doi.org/10.4995/heritage2022.2022.15700.
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El patrimonio cultural está en peligro en Siria, como en todas las ciudades del patrimonio mundial. Los edificios históricos han sido destruidos radicalmente por el conflicto y las comunidades han sido desplazadas. Muchos factores han contribuido a esta situación, como las estrategias de preservación inadecuadas antes de la guerra y la falta de conciencia de las comunidades locales sobre la importancia de su patrimonio. La incapacidad de las comunidades locales para contribuir a la protección de los sitios culturales se debe a la falta de recursos y conocimientos, además de su perspectiva del patrimonio como un obstáculo para el desarrollo y una carga económica en lugar de una fuente de orgullo e identidad. Por lo tanto, este artículo busca investigar la noción de patrimonio como un proceso acumulativo de producción cultural comunitaria en el tiempo y un elemento clave de la identidad. El patrimonio cultural refuerza la interrelación entre las comunidades y la tierra al restablecer conexiones que a menudo son parte de la construcción de paz. Este documento investiga a través de encuestas cualitativas y estadísticas la brecha problemática entre el patrimonio cultural y las comunidades locales en Siria. Además, se analiza la “visualización en 3D” como un catalizador potencial para llevar a cabo una participación exitosa de la comunidad local a través de sus jóvenes en la salvaguardia de su patrimonio cultural. La visualización 3D tiene un papel importante en la distribución del conocimiento (a nivel nacional e internacional) sobre el patrimonio a través del proceso de su creación, participación y el producto 3D. Además, las instituciones académicas tienen un papel importante en la difusión del conocimiento sobre el patrimonio a través de programas de educación patrimonial.
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Zhan, Guodong David, Nicholas Lyons, Msalli Al Otaibi, Duanwei He y Andrew Robertson. "A First Look at 100% Thermally Stable Polycrystalline Diamond (PCD) for Oil & Gas Drilling". En SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210352-ms.
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Abstract Since the late 1970's, research on the efficiency and cutting life of polycrystalline diamond compact (PDC) cutters identified elevated temperature due to frictional heating as one of the primary accelerants of wear to the diamond cutting edge. Temperatures as low as 700 °C activate the back-conversion process, whereby diamond transforms into graphite, due to the presence of catalytic metal in the diamond structure. The Oil and Gas industry responded by investing years developing technologies to reduce the temperatures that PDC's experience in application via improved hydraulics for cooling, higher quality surface finishes to reduce friction, and improved thermal stability via material structure and chemical treatments. PDC cutter technology has progressed substantially in the last 30+ years, but the challenge of synthesizing a perfectly thermally stable PDC still remains unmet until now. Recently, Zhan (2018, 2020, 2021a and 2021b) first developed a new strategy to synthesize ultrastrong and catalyst-free polycrystalline diamond (CFPCD) or binderless PDC cutters with a new world record as the hardest and tough diamond material and the highest thermal stability up to 1,400°C via his invented ultra-high pressure and ultra-high temperature (UHPHT) technology, which is three to seven times higher than conventional PDC cutters used in the industry. An initial laboratory study of a new catalyst-free extreme high pressure, high temperature CFPCD material provides the first instance of a catalyst metal free polycrystalline diamond structure that actually boosts rock cutting performance above and beyond that of the current state-of-the-art PDCs. Proof of concept CFPCD specimens were evaluated against commercial, state-of-the-art non-leached (NL) and deep leached (DL) PDC cutters in the lab. Two CFPCD grades, A & B, were run through a series of tests to evaluate their potential for rock cutting and, ultimately, for use in oil & gas drilling applications. Laboratory testing was conducted on vertical borer wear tests, KIC fracture toughness tests, and thermal degradation monitoring tests. Lab results reveal a threshold that must be exceeded in the synthesis of catalyst-free CFPCDs to achieve sufficient diamond intergrowth and structural integrity to surpass the current state-of-the-art DL PDCs. CFPCD grade A wore equivalently to a commercially available NL cutter and exhibited a toughness comparable to that of commercially available DL PDC material. Grade B, synthesized at a significantly higher pressure than grade A, cut 5.7 times the distance of a commercial NL PDC for an equivalent wearscar volume, and exhibited a 160 % reduction in wear volume comparing volume of diamond worn to volume of rock cut (or G ratios) to DL PDC after cutting the equivalent of roughly 50 miles of rock. The wearscar surface of Grade B also exhibited excellent integrity with no cracking or chipping damage compared to Grade A and commercial PDC grades. This is the first documented instance of a catalyst-free PDC achieving the best wear performance and integrity (fracture toughness) than the current PDC cutters offering on the market. Thermal stability limits of PDC cutters has greatly improved in the past 20 years, but the best commercial PDC's still rely on extending leach depths with certain performance limits. For the first time in the industry, there is a PDC material than shifts this boundary without the use of catalysts and leaching technology, producing a truly differentiable PDC cutter.
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Bolotov, Vasiliy Alexandrovich, Serguei Fedorovich Tikhov, Konstantin Radikovich Valeev, Vladimir Timurovich Shamirzaev y Valentin Nikolaevich Parmon. "SELECTIVE FORMATION OF LINEAR ALPHA-OLEFINS VIA MICROWAVE CATALYTIC CRACKING OF LIQUID STRAIGHT-CHAIN ALKANES". En Ampere 2019. Valencia: Universitat Politècnica de València, 2019. http://dx.doi.org/10.4995/ampere2019.2019.9894.
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Linear even-carbon-number alpha-olefins (LAO) with four or more carbon atoms are important compounds of high demand in chemical industry as precursors of a wide range of value-added chemicals [1]. LAO are used as co-monomers for polyethylene production, for the production of alcohols (mainly in detergents and plasticizers) and for synthesis of polyalphaolefins (used in synthetic lubricants). Alpha-olefins (C4, C6, C8 and C10) are mainly used to produce poly(vinyl chloride) plasticizers, high-density and linear low-density polyethylene to impart the stress-crack resistance. C10–C14 alpha-olefins can be used to synthesize linear alkylbenzene sulfonates (synthetic detergents). A conventional route to produce alpha-olefins is oligomerization of ethylene. The process provides production of high quality alpha-olefins but is very costly. If not oligomerization, LAO can be produced by thermal cracking of waxy paraffins but the product is not pure and contains numerous internal olefins, dienes and paraffin impurities. The process is conducted in the vapor phase at relatively low cracking temperatures and needs rapid quenching to prevent side reactions such as isomerization or cyclization. In our previous work [2], we showed that the selectivity to alpha-olefins can be increased considerably via catalytic cracking of n-alkanes under selective MW heating of catalysts. In the present work, the general regularities of MW cracking of n-alkanes are presented. Porous ceramic matrix Al2O3/Al composites (ceramometals) and various carbon materials (CM) having high dielectric losses were studied as supports of the catalysts. MW cracking was conducted with n-C16H34 and n-C28H58. The influence particle size and surface morphology of ceramometals and CM on the structural and group composition of the products was studied. It was established that LAO (C2-C23) and n-alkanes (C2-C26) were the main cracking products under selective MW heating of the used supports. The quantitative analysis of the products demonstrated that the liquid-phase process is more selective to alpha-olefins at the MW catalytic cracking than at the convectional thermal cracking. Silica modification of the surface of CM was shown to suppress spark discharge (usually observed at MW heating of CM); hence, the thermal cleavage of C-C bonds on the CM surface but not in the plasma discharge contributes the most to the formation of radicals. It was shown that the selectivity to liquid alpha-olefin could be more than 85 % under MW heating of cermets in region of the E - field node and decrease considerably in the region of H - field node.
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Jamaleddine, Tarek J. y Ramsey M. Bunama. "CFD Modelling of the Dehydrogenation Reaction of Isobutane to Isobutylene in a Fixed Bed Reactor". En ASME 2016 Heat Transfer Summer Conference collocated with the ASME 2016 Fluids Engineering Division Summer Meeting and the ASME 2016 14th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/ht2016-1071.
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The catalytic dehydrogenation reaction of isobutane to isobutylene is simulated in a commercial-scale heterogenous fixed bed reactor (FBR). The porous medium method in ANSYS Fluent combined with the reaction model capability was utilized to predict the flow behavior and species transport in a bed of spherical particles. Physical and material properties of a dehydrogenating catalyst of Chromium Oxide (Cr2O3) on Aluminum Oxide Support (Al2O3) were employed in the model. Several reaction models were implemented using a customized User-defined Function (UDF) subroutine. Simulation results were validated against literature data for a similar process. Good agreement was observed for the conversion of alkanes to alkenes within acceptable accuracy. It is concluded that the power-law model showed the least fit for the feed conversion and product selectivity compared to the other studied reaction models.
Informes sobre el tema "Lay catalysis"
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Fontecave, Marc y Candel Sébastien. Quelles perspectives énergétiques pour la biomasse ? Académie des sciences, enero de 2024. http://dx.doi.org/10.62686/1.
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Le débat public concernant l’avenir du mix énergétique français à l’horizon 2050 a longtemps été réduit à la seule considération de son volet électrique, dans une opposition entre énergie nucléaire et énergies renouvelables (EnR). Pourtant, la part non-électrique de notre consommation énergétique constitue clairement aujourd’hui un des principaux défis de la transition climatique et énergétique. Actuellement issue du pétrole, du gaz et du charbon, elle constitue l’angle mort des divers scénarios énergétiques disponibles, alors qu’elle restera encore indispensable, notamment dans le secteur de la mobilité et de la production de chaleur. Le Comité de prospective en énergie (CPE) de l’Académie des sciences examine ici les ressources énergétiques et carbonées pouvant être tirées de la biomasse, qui présente des atouts certains en permettant le stockage de l’énergie sous forme de biogaz ou de biocarburants, et les perspectives raisonnables offertes par celles-ci dans le mix énergétique national à l’horizon 2050. Le présent rapport se focalise sur les aspects scientifiques et technologiques, sans occulter certaines considérations environnementales, économiques, sociales, et de souveraineté nationale, abordés à la lumière de la littérature disponible et de l’audition d’experts des divers domaines considérés. Après avoir défini la notion de biomasse dans sa diversité, le rapport décrit les différentes bioénergies possibles et leurs limites. Les utilisations actuelles de la biomasse en France sont évaluées et comparées aux perspectives envisagées à l’horizon 2050 au regard du potentiel réellement mobilisable, pour lequel il existe une grande variation dans les estimations proposées, et des technologies nécessaires à sa transformation, qui restent, pour la plupart, coûteuses et de faible maturité. Ainsi, cette analyse montre notamment que le besoin d’énergie non-électrique, tel qu’il est défini dans le scénario de référence fourni par Réseau de transport d’électricité (RTE), sera difficile – pour ne pas dire impossible - à atteindre avec la seule biomasse produite en France : le bouclage énergétique 2050 passera nécessairement par un maintien d’importations de gaz naturel et par de nouvelles importations de biomasse et/ou de bioénergie introduisant des dépendances nouvelles et exportant les risques associés à leur utilisation massive. Le rapport rappelle que la bioénergie reste l’énergie la moins favorable en termes d’empreinte spatiale et que la biomasse a, sur toute la chaîne des valeurs, un faible retour énergétique. Sa plus grande mobilisation, qui ne devra pas se faire au détriment de la sécurité alimentaire humaine et animale, ni au détriment des éco-services rendus par la biosphère, aura des impacts environnementaux certains qu’il faudrait estimer avec rigueur. Enfin, le remplacement de la pétrochimie industrielle par une nouvelle « carbochimie biosourcée » va nécessiter des efforts considérables d’adaptation des procédés et de recherche et développement dans le domaine de la catalyse, de la chimie de synthèse et des biotechnologies. Ces conclusions conduisent le CPE à formuler des recommandations concernant : 1.La nécessaire amélioration de la concertation entre les divers organismes et agences pour aboutir à une estimation rigoureuse et convergente des ressources potentielles, 2.La réalisation de bilans carbone des diverses filières et d’analyses en termes de retour énergétique des investissements envisagés, pour s’assurer de la soutenabilité et du gain en carbone qui ne sont pas acquis pour le moment, 3.Le soutien au déploiement de la recherche et développement des filières de biocarburants de seconde génération pour accroitre leur maturité industrielle, 4.La poursuite du développement d’une chimie organique de synthèse biosourcée, 5.La priorité à établir dans l’utilisation de la biomasse pour les usages qui ne pourront être décarbonés par l’électricité, passant par une politique publique permettant de résoudre les conflits d’usages, 6.La nécessité de concertation des politiques énergétique et agroalimentaire de notre pays.
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García Zaballos, Antonio y Ginya Truitt Nakata. Bridging Gaps, Building Opportunity: Broadband as a Catalyst of Economic Growth and Social Progress in Latin America and the Caribbean: A View from the Industry. Inter-American Development Bank, mayo de 2012. http://dx.doi.org/10.18235/0009027.
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This report is intended to encourage and reinforce the efforts of policymakers and industry stakeholders throughout the region to accelerate broadband deployment. The report has two primary aims. The first is to help identify public policy and regulatory issues that need to be addressed in order to eliminate the digital divide within and between LAC countries, and between the region and the world's leading broadband nations. The second is to highlight the range of options that policymakers have in achieving that goal by offering examples of specific solutions implemented in the region and elsewhere that have proved successful in accelerating broadband deployment and adoption.
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Seneviratne, Kalinga. Exploring the role of Buddhist monks’ and nuns’ engagement in community development as catalysts for social change and sustainable development in Lao People’s Democratic Republic: A case study of the Buddhism for Development Project at Ban Bungsanthueng, Nongbok District, Khammouane Province, by Toung Eh Synuanchanh. Unitec ePress, noviembre de 2018. http://dx.doi.org/10.34074/thes.revw4499.
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The topic of this research report is an important one in the context of Asia’s rapid economic development in recent years, and the need to rethink development policy and especially methodologies of development communications, so the mistakes of the past will not be replicated. Thus, the study is an important initiative at this period of time. The research takes as a case study the Buddhism for Development Project (BDP) implemented at Ban Bungsanthueng village in the Khammouane Province by its Buddhist Volunteer Spirit for Community network (BVSC network). The fieldwork took place at the BDP’s training centre in Vientiane and the Buddhist initiatives at Ban Bungsanthueng. The research demonstrates how the BDP and its network apply participatory approaches through interpersonal communication, such as sermon delivery, Dhamma (Buddhist teachings) talk, and daily interaction with villagers and project members.
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S’attaquer aux tabous de la communication pour le changement social et de comportement à Niamey et Abidjan: Évaluation de la campagne médiatique Merci Mon Héros. Population Council, 2022. http://dx.doi.org/10.31899/sbsr2022.1028.
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Merci Mon Héros (MMH) est une campagne médiatique qui catalyse les jeunes en tant que co-leaders pour améliorer la communication intergénérationnelle et les résultats des jeunes en matière de planification familiale et de santé reproductive. Le projet Breakthrough RESEARCH a été chargé d'évaluer la campagne MMH. Cette note met en évidence d'importantes conclusions d'évaluation et des recommandations pour le renforcement de la communication intergénérationnelle dans deux lieux prioritaires : Niamey, au Niger et Abidjan, en Côte d'Ivoire. --- Merci Mon Héros (MMH) is a mixed media campaign that catalyzes young people as co-leaders to improve intergenerational communication and young people’s family planning and reproductive health outcomes. The Breakthrough RESEARCH project―USAID’s flagship investment in social and behavior change research and evaluation―was tasked with evaluating the MMH campaign. This brief highlights important evaluation findings and recommendations for strengthening intergenerational communication in two priority locations—Niamey, Niger and Abidjan, Côte d’Ivoire.
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Rapport Annuel 2023: Découvrez le pouvoir de l'action collective. Rights and Resources Initiative, abril de 2024. http://dx.doi.org/10.53892/xltl2276.
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Cette année 2023 a été une période de renforcement des mouvements et de construction de relations avec les détenteurs de droits, les alliés et les donateurs qui sont à la base de la mission de RRI. Des sommets des Andes péruviennes aux plaines désertiques d’Afrique de l’Est en passant par les mangroves côtières d’Indonésie, notre coalition travaille d’arrache-pied pour créer les conditions propices à la reconnaissance des droits. En continuant à tirer parti de nos diverses forces, nous continuerons à catalyser de véritables changements pour l’amélioration de la planète et de ses habitants. Notre rapport annuel n’est qu’un aperçu de quelques-uns des succès essentiels qui continuent à nous stimuler dans notre quête de communautés plus inclusives, plus équitables et plus durables, au service des personnes et de la planète.