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Showing 1 to 20 of 20 for “"Hydrogen permeation"”.
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Hydrogen permeation in uncoated and coated X60steel
The sustainable storage and transport of hydrogen represent major challenges for the deployment of renewable energy systems, requiring a comprehensive understanding of hydrogen–material interactions in pipeline steels and effective strategies to limit hydrogen uptake. This PhD research investigates …
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Microstructure influence on hydrogen permeation and embrittlement of 4140 steel
En esta tesis se han realizado tratamientos térmicos de temple y revenido y diferentes tratamientos de normalizado y recocido sobre un acero estructural de media aleación (grado 4140) y se ha analizado primero su influencia en la microestructura y propiedades mecánicas fundamentales. A …
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Hydrogen Permeation Through Nickel And Nickel Alloys: Surface Reactions And Trapping
… metal foils have characteristic features whether permeation is diffusion controlled, is influenced by surface reactions or affected by internal trapping.<br></br><br></br>Analysis of data obtained for hydrogen permeation through nickel show that hydrogen is dissociatively chemisorbed in …
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HYPERION: A HYdrogen PERmeatION Experiment to Quantify Hydrogen Transport in Fusion-Relevant Molten Salts
The measurement of hydrogen transport properties of molten salts like FLiBe is crucial for the development of advanced nuclear technologies like lithium-bearing liquid immersion breeding blankets for fusion reactors. Tritium production and the quantification of its mobility in these materials is …
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Development and testing of inorganic membranes for hydrogen separation and purification in a catalytic membrane reactor.
… been identified as the membranes of choice in hydrogen separation and purification processes due to their infinite selectivity to hydrogen when defect-free. Despite their potentials in hydrogen processes, palladium membranes pose challenges in terms of cost and embritllement, which occurs when …
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STUDY OF STRUCTURAL, THERMAL, HYDROGENATION AND COMPOSITIONAL PROPERTIES OF NI-BASED AMORPHOUS MEMBRANES USING EXPERIMENTAL AND COMPUTATIONAL METHODS
Hydrogen is considered as a promising source of energy because of its properties such as abundant availability, high energy conversion efficiency, low-density, solid-state storage potential, and most importantly zero emission from energy conversion devices, such as fuel cell. End product from …
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Estudo da permeação de hidrogênio e fragilização pelo hidrogênio de um aço API 5L X80
… comes the concern about the risks involving hydrogen diffusion and hence, embrittlement due to severe operational conditions and corrosive environment containing hydrogen sulphide (H2S). Although many efforts have been made to predict and understand those phenomena, the mechanisms involving …
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Hydrogen Transport and Hydrogen Embrittlement in Stainless Steels (Diffusion, Permeation, Solubility, Slow Crack Growth)
In order to understand the kinetics of gaseous hydrogen-induced slow crack growth (SCG) in metastable austenitic stainless steels, hydrogen permeation and/or cracking velocity were measured and compared for three types of stainless steels. These included austenitic, ferritic, and duplex …
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Estudo do processamento termomecânico de liga experimental de zircônio e seu efeito nas propriedades mecânicas e formação de hidretos
… and low neutron absorption. The interaction with hydrogen during the operation of the reactor leads to the formation of hydrides, dependent on the presence of crystalline discontinuities and on the texture of the material. This work aimed to validate the thermomechanical processing of an …
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Avaliação de permeação de hidrogênio em célula multiteste e susceptibilidade ao trincamento sob tensão em presença de sulfeto de um aço de especificação API 5L X70
… of CO2 (carbon dioxide), and especially of H2S (hydrogen sulphide), which accelerate the materials corrosion in contact with petroleum. In this environment that the API 5L X70 steel studied in this research operates. In this context, the work present the effect of different concentrations of H2S …
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Hydrogen embrittlement testing of austenitic stainless steels SUS 316 and 316L
The imminent emergence of the hydrogen fuel industry has resulted in an urgent mandate for very specific material testing. Although storage of pressurized hydrogen gas is both practical and attainable, demands for increasing storage pressures (currently around 70 MPa) continue to present unexpected …
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Hydrogen transport in and through niobium
… roles of bulk diffusion and surface processes in hydrogen transport in and through niobium. Bulk hydrogen and deuterium diffusivities and permeabilities were measured at high temperatures (700 -1400 K) using diffusion controlled permeation methods. At lower temperatures, surface controlled …
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Studies of the Ethanol Steam Reforming Reaction in a Membrane Reactor
… of the ESR reaction. Studies of the effect of hydrogen permeance on the ESR reaction at 623 K were performed in MRs equipped with silica-based and palladium-based membranes of different hydrogen permeances, and the highest ethanol conversion enhancement of 44 % and hydrogen molar flow …
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Water selective MFI zeolite membranes for application in the Fischer Tropsch Synthesis
… gas applied to remove the permeate. Single gas permeation measurements on a blank support shows that viscous and knudsen flow are the dominant transport mechanisms in the support. A single gas permeation model for the zeolite membranes show that viscous and knudsen flow still dominate in pure …
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Experimental and Modeling Studies of the Methane Steam Reforming Reaction at High Pressure in a Ceramic Membrane Reactor
… preparation of a novel inorganic membrane for hydrogen permeation and its application in a membrane reactor for the study of the methane steam reforming reaction. The investigations include both experimental studies of the membrane permeation mechanism and theoretical modeling of mass transfer …
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Microstructure Optimization to Prevent Hydrogen-Induced Cracking of API X70 Pipeline Steels in Sour Environments
… categories: stress corrosion cracking (SCC) and hydrogen assistant cracking (HAC). Hydrogen-induced cracking (HIC) is the main cause of pipeline steels failure in sour environments, which is categorized as a type of HAC. In this type of failure, hydrogen atoms accumulate in the steel and cause …
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Composite inorganic membranes for hydrogen reaction, separation and purification.
Silica-alumina composite membranes for hydrogen separation and high temperature chemical reactions were prepared using both conventional and modified dip-coating techniques. These were deposited on commercially available a.-alumina macroporous support of 10 millimetre (mm) outer diameter, 7 mm …
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THE ROLES OF MATERIAL, SURFACE, & MICROSTRUCTURAL EFFECTS IN DEVELOPING CERAMICS FOR ENERGY APPLICATIONS
… which reduces their ability to permeate hydrogen. Through changing the dopants used in existing perovskite compositions, the electronic conductivity was improved dramatically allowing its use as an n-type conductor. This was achieved by using Pr as a dopant, which introduces electronic …
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Effect of microstructural constituents on hydrogen diffusion in multiphase alloys
… is a strong link between microstructure and hydrogen diffusion and embrittlement in all metallic systems, the correlation between the two is poorly documented. It is, however, sorely needed as the current research shows that by quantifying the type and density of defects along with their …
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Caratterizzazione di membrane metalliche e ionomeriche per applicazioni energetiche
… characterization of metallic membranes for the hydrogen purification from steam reforming process and also of perfluorosulphonic acid ionomeric (PFSI) membranes suitable as electrolytes in fuel cell applications. The experimental study of metallic membranes was divided in three sections: …