1,242 research outputs found

    Microstructure, magneto-transport and magnetic properties of Gd-doped magnetron-sputtered amorphous carbon

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    The magnetic rare earth element gadolinium (Gd) was doped into thin films of amorphous carbon (hydrogenated \textit{a}-C:H, or hydrogen-free \textit{a}-C) using magnetron co-sputtering. The Gd acted as a magnetic as well as an electrical dopant, resulting in an enormous negative magnetoresistance below a temperature (T′T'). Hydrogen was introduced to control the amorphous carbon bonding structure. High-resolution electron microscopy, ion-beam analysis and Raman spectroscopy were used to characterize the influence of Gd doping on the \textit{a-}Gdx_xC1−x_{1-x}(:Hy_y) film morphology, composition, density and bonding. The films were largely amorphous and homogeneous up to xx=22.0 at.%. As the Gd doping increased, the sp2sp^{2}-bonded carbon atoms evolved from carbon chains to 6-member graphitic rings. Incorporation of H opened up the graphitic rings and stabilized a sp2sp^{2}-rich carbon-chain random network. The transport properties not only depended on Gd doping, but were also very sensitive to the sp2sp^{2} ordering. Magnetic properties, such as the spin-glass freezing temperature and susceptibility, scaled with the Gd concentration.Comment: 9 figure

    The efficacy of low vision devices for students in specialized schools for students who are blind in Kathmandu Valley, Nepal

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    In Nepal, children with low vision attend specialized schools for students who are totally blind and are treated as if they were totally blind. This study identified children with low vision and provided low vision devices to them. Of the 22% of the students in the school who had low vision, 78.5% benefited from the devices. Proper devices and counseling improved the quality of life of a significant number of these students. ©2008 AFB, All Rights Reserved

    Nagging and Other Drinking Control Efforts of Spouses of Uncooperative Alcohol Abusers: Assessment and Modification

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    This article presents a conception of spouse drinking control and an approach to assessment and modification to reduce the customary drinking control efforts of spouses of alcohol abusers unmotivated to enter treatment. Modification of the nonalcoholic spouse’s customary drinking control is offered as an important early step in helping to prepare him or her to become a positive rehabilitative influence. Based on its use in unilateral family therapy with 68 spouses of uncooperative alcohol abusers, procedural guidelines, criteria for use, and two case examples from a crossover experimental dyad are described. Also presented are clinical results illustrating the success of the program, benefits and conditions relating to its use, and areas of possible application

    Wetting-regulated gas-involving (photo)electrocatalysis: biomimetics in energy conversion

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    (Photo)electrolysis of water or gases with water to species serving as industrial feedstocks and energy carriers, such as hydrogen, ammonia, ethylene, propanol, etc., has drawn tremendous attention. Moreover, these processes can often be driven by renewable energy under ambient conditions as a sustainable alternative to traditional high-temperature and high-pressure synthesis methods. In addition to the extensive studies on catalyst development, increasing attention has been paid to the regulation of gas transport/diffusion behaviors during gas-involving (photo)electrocatalytic reactions towards the goal of creating industrially viable catalytic systems with high reaction rates, excellent long-term stabilities and near-unity selectivities. Biomimetic surfaces and systems with special wetting capabilities and structural advantages can shed light on the future design of (photo)electrodes and address long-standing challenges. This article is dedicated to bridging the fields of wetting and catalysis by reviewing the cutting-edge design methodologies of both gas-evolving and gas-consuming (photo)electrocatalytic systems. We first introduce the fundamentals of various in-air/underwater wetting states and their corresponding bioinspired structural properties. The relationship amongst the bubble transport behavior, wettability, and porosity/tortuosity is also discussed. Next, the latest implementations of wetting-related design principles for gas-evolving reactions (i.e. the hydrogen evolution reaction and oxygen evolution reaction) and gas-consuming reactions (i.e. the oxygen reduction reaction and CO2 reduction reaction) are summarized. For photoelectrode designs, additional factors are taken into account, such as light absorption and the separation, transport and recombination of photoinduced electrons and holes. The influences of wettability and 3D structuring of (photo)electrodes on the catalytic activity, stability and selectivity are analyzed to reveal the underlying mechanisms. Finally, remaining questions and related future perspectives are outlined.National Research Foundation (NRF)This work is supported by the eCO2EP programme funded by the Singapore National Research Foundation under its Campus for Research Excellence and Technological Enterprise (CREATE) programme through the Cambridge Centre for Advanced Research and Education in Singapore (CARES) and the Berkeley Educational Alliance for Research in Singapore (BEARS). W. S. Y. W and D. V. acknowledge the European Union’s Horizon 2020 research and innovation program LubISS No. 722497 and the ERC Advanced Grant (883631 DynaMo)

    Ariel - Volume 2 Number 6

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    Editors Richard J. Bonanno Robin A. Edwards Associate Editors Steven Ager Stephen Flynn Shep Dickman Tom Williams Lay-out Editor Eugenia Miller Contributing Editors Michael J. Blecker W. Cherry Light James J. Nocon Lynne Porter Editors Emeritus Delvyn C. Case, Jr. Paul M. Fernhof

    Experimental demonstrations of spontaneous, solar-driven photoelectrochemical water splitting

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    Laboratory demonstrations of spontaneous photoelectrochemical (PEC) solar water splitting cells are reviewed. Reported solar-to-hydrogen (STH) conversion efficiencies range from 10% STH efficiency using potentially less costly materials have been reported. Device stability is a major challenge for the field, as evidenced by lifetimes of less than 24 hours in all but a few reports. No globally accepted protocol for evaluating and certifying STH efficiencies and lifetimes exists. It is our recommendation that a protocol similar to that used by the photovoltaic community be adopted so that future demonstrations of solar PEC water splitting can be compared on equal grounds

    Cutting out continuations

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    In the field of program transformation, one often transforms programs into continuation-passing style to make their flow of control explicit, and then immediately removes the resulting continuations using defunctionalisation to make the programs first-order. In this article, we show how these two transformations can be fused together into a single transformation step that cuts out the need to first introduce and then eliminate continuations. Our approach is calculational, uses standard equational reasoning techniques, and is widely applicable

    A systematic review of community participation measures for people with intellectual disabilities

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    Background: Community participation is considered a fundamental aspect of quality of life and one of the essential goals of services for people with intellectual disabilities (ID), yet there is no agreed way of measuring community participation. Method: Two systematic searches were performed across eight electronic databases to identify measures of community participation and identify validation studies for each measure. Measures were included if they were developed for adults with ID, measured extent of participation and had published information regarding content and psychometric properties. Each measure was evaluated on the basis of psychometric properties and in relation to coverage of nine domains of community participation from the International Classification of Functioning, Disability and Health (ICF). Results: Eleven measures were selected with the quality rating scores varying substantially ranging from 2-11 of a possible 16. Conclusions: The majority of measures were not sufficiently psychometrically tested. Findings suggest a need for the development of a psychometrically robust instrument
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