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Showing 1 to 20 of 21 for “"Hydrogen absorption"”.
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Electrochemical Hydrogen Absorption by Zr-Cu-Al-Ni Metallic Glasses
Effect of electrochemical absorption of hydrogen has been studied on the Zr-based amorphous alloys. The influence of hydrogen absorption on the stability of the amorphous phase and its crystallisation was investigated. Additionally, the cathodic hydrogen reaction mechanism on the surface of the …
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Dynamics of hydrogen absorption into the N(111) bulk : spectroscopic identification and chemistry of subsurface hydrogen
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 1991.
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Investigation of Pd-Ti and Ni-Ti Multilayer Thin Films for Enhanced Hydrogen Storage Capacity
… of compact and secure storage solutions for hydrogen in solid-state materials presents significant challenges and demands. High-capacity storage technologies that operate effectively at low pressures and exhibit favourable kinetics in absorption and desorption are essential for hydrogen …
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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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Recovery Of Hydrogen And Helium From Their Mixtures Using Metal Hydrides
Waste streams of hydrogen and helium mixtures are produced at the Kennedy Space Center during purging of the hydrogen systems and supply lines. This process is done prior to and after hydrogen servicing. The purged waste gases are lost to the atmosphere, resulting in an annual loss of 2 million and …
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A Computational Framework for Long-Term Atomistic Analysis of Solute Diffusion in Nanomaterials
… groups of numerical experiments that simulate hydrogen mass transport in palladium. Specifically, the framework is validated against a classical lattice random walk model. Its capability to capture the atomic details in nanomaterials over a long diffusive time scale is also demonstrated. In …
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Untangling compact and diffuse ionized emission toward galactic hii regions
HII regions are clouds of ionized hydrogen gas surrounding B0- and O-type stars. The ionized hydrogen in these regions emits both radio recombination line (RRL) and also thermal radio continuum. Diffuse ionized hydrogen, known as the 'Warm Ionized Medium' (WIM) also exists in the Galaxy. The WIM …
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High Temperature And Pressure Resonant Ultrasound Spectroscopy Study Of Metal Hydride Systems
… includes study of the equilibrium dynamics of hydrogen absorption/desorption in metal hydrides. A color map of the equilibrium dynamics pattern was developed and correlation between the color map and the palladium hydride phases was established.
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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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The hydrogen-induced piezoelectric effect in InP HEMTs
Hydrogen exposure of III-V HEMTs has been shown to cause a threshold voltage shift, [delta] V[sub]T. This is a serious reliability concern. This effect has been attributed to a H-induced piezoelectric effect. Formation of TiH[sub]x expands the Ti layer in the gate, causing mechanical stress in the …
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HYDROGEN STORAGE CHARACTERISTICS OF ZIRCONIUM((IRON-X)(CHROMIUM-1-X))(,2).
… intermetallic compounds exhibit desirable hydrogen storage characteristics, such as high hydrogen capacities and rapid hydriding/dehydriding kinetics. In particular, research in recent years has focussed on so-called pseudobinary alloys (A(B(,x)B(,1-w)')(,2)). The additional transition …
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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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Synthesis and characterisation of hybrid Zn0-carbon nanostructures for potential applications in hydrogen storage
… and to investigate if they can be used as the hydrogen storage materials. The synthesis of ZnO nanoparticles (ZnO NPs) was carried out using direct current (DC) reactive magnetron sputtering at different deposition times, pressure and temperature, and were used as a seeding in the synthesis of …
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Effects of hydrogen in an aluminium-magnesium-silicon alloy during the production of extrusion ingots
Hydrogen causes defects, for which aluminiurn alloy products are rejected. The behaviour of hydrogen in aluminium-magnesium-silicon alloy extrusion ingots, has been studied throughout the course of manufacture from freshly reduced aluminium. It is shown that hydrogen in the liquid metal is produced …
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Solid State Studies of [ReH9]-2 Complexes from Ambient to Extreme Conditions: High Volumetric Capacity Hydrogen Storage
… As the simplest and most abundant element, hydrogen has the potential to energy system. Solid state transition metal hydrides based on Re and transition metals are very attractive materials for hydrogen and energy storage due to their large volumetric capacity, providing a safe and efficient …
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Kinetics of hydrogen evolution and absorption during electrochemical reactions as determined by monitoring the volume of hydrogen bubbles
… H on an electrode which does not absorb hydrogen, and by using a hydrogen saturated solution, it is possible to calibrate the output e.m.f. These results are compared with those obtained using an electrode which does absorb hydrogen and this makes it possible to calculate the quantitative …
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Oxidation of Aluminium-Magnesium alloys at elevated temperature in the solid, semi-liquid and liquid states
… with consequent disruptive effects caused by hydrogen absorption by the alloy. The addition of 0.003% Be to Al-8% Mg alloy decreased the oxidation rate markedly by toughening the MgO films preventing cracking and hence the nucleation of tertiary MgO. Small additions of Mn or Zr offset the …
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Synthesis Imaging with Vector Sensor Arrays
… cosmic dark age signal in the redshifted 21-cm hydrogen absorption line, detecting exoplanetary auroral emissions which lead to inferences about magnetic fields and atmospheres, and characterizing the effects of solar wind and coronal mass ejections on the magnetospheres of solar system planets. …
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Upscaling effect in the preparation of metal hydride materials
… A=Ti, Zr ; B= Mn,Cr, Ni, Fe, V, Cu for use in hydrogen storage was investigated. In Ti-Zr based AB2 metal hydrides, the effects of composition, microstructure, and hydrogen sorption properties were examined using Scanning electron microscope (SEM), Energy dispersive x-ray spectroscopy (EDS), …
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Decoration of graphene sheets with metal and metal oxide nanostructures by low-pressure plasma deposition
… onto graphene sheets were studied for the hydrogen absorption and desorption at two different temperatures 330 oC and 360 oC at 2 and 8 bars pressure. The hydrogen up taking capacity for the decorated graphene sheets with Mg nanoparticles was 3 wt. % in whole composite. However, the up …
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