164 research outputs found

    A room temperature polyaniline nanofiber hydrogen gas sensor

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    Abstract—Electro-conductive polyaniline (PANI) nanofiber based Surface Acoustic Wave (SAW) gas sensors have been investigated with hydrogen (H2) gas. A template-free, rapidly mixed method was employed to synthesize polyaniline nanofibers using chemical oxidative polymerization of aniline. The nanofibers were deposited onto a layered ZnO/64º YX LiNbO3 SAW transducer for gas sensing applications. The novel sensor was exposed to various concentrations of H2 gas at room temperature. The sensor response, defined as the relative variation in operating frequency of oscillation due to the introduction of the gas, was 3.04 kHz towards a 1 % H2 concentration. A relatively fast response time of 8 sec and a recovery time of 60 sec with good repeatability were observed at room temperature. Due to room temperature operation, the novel gas sensor is promising for environmental and industrial applications. I

    Polyaniline nanofiber based surface acoustic wave gas sensors – effect of nanofiber diameter on H2 response

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    Kourosh and Kaner, Richard B. 2007, Polyaniline nanofiber based surface acoustic wave gas sensors – effect of nanofiber diameter on H2 response, IEEE sensors journal, vol. 7, no. 2, pp. 213-218. Available from Deakin Research Online

    DIgital Alcohol Management ON Demand (DIAMOND) feasibility randomised controlled trial of a web-based intervention to reduce alcohol consumption in people with hazardous and harmful use versus a face-to-face intervention: protocol.

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    BACKGROUND: "Hazardous and harmful" drinkers make up approximately 23 % of the adult population in England. However, only around 10 % of these people access specialist care, such as face-to-face extended brief treatment in community alcohol services. This may be due to stigma, difficulty accessing services during working hours, a shortage of trained counsellors and limited provision of services in many places. Web-based alcohol treatment programmes may overcome these barriers and may better suit people who are reluctant or unable to attend face-to-face services, but there is a gap in the evidence base for the acceptability, effectiveness and cost-effectiveness of these programmes compared with treatment as usual (TAU) in community alcohol services. This study aims investigate the feasibility of all parts of a randomised controlled trial (RCT) of a psychologically informed web-based alcohol treatment programme called Healthy Living for People who use Alcohol (HeLP-Alcohol) versus TAU in community alcohol services, e.g. recruitment and retention, online data collection methods, and the use and acceptability of the intervention to participants. METHODS: A feasibility RCT delivered in north London community alcohol services, comparing HeLP-Alcohol with TAU. Potential participants are aged ≥18 years referred or self-referred for hazardous and harmful use of alcohol, without co-morbidities or other complex problems. The main purpose of this study is to demonstrate the feasibility of recruiting participants to the study and will test online methods for collecting baseline demographic and outcome questionnaire data, randomising participants and collecting 3-month follow-up data. The acceptability of this intervention will be measured by recruitment and retention rates, automated log-in data collection and an online service satisfaction questionnaire. The feasibility of using tailored text message, email or phone prompt to maintain engagement with the intervention will also be explored. Results of the study will inform a definitive Phase 3 RCT. RESULTS: Recruitment started on 26 September 2014 and will run for 1 year. CONCLUSION: The proposed trial will provide data to inform a fully powered non-inferiority effectiveness and cost-effectiveness RCT comparing HeLP-Alcohol with TAU. TRIAL REGISTRATION: ISRCTN31789096

    New Developments in Brief Interventions to Treat Problem Drinking in Nonspecialty Health Care Settings

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    The delivery of brief interventions (BIs) in health care settings to reduce problematic alcohol consumption is a key preventive strategy for public health. However, evidence of effectiveness beyond primary care is inconsistent. Patient populations and intervention components are heterogeneous. Also, evidence for successful implementation strategies is limited. In this article, recent literature is reviewed covering BI effectiveness for patient populations and subgroups, and design and implementation of BIs. Support is evident for short-term effectiveness in hospital settings, but long-term effects may be confounded by changes in control groups. Limited evidence suggests effectiveness with young patients not admitted as a consequence of alcohol, dependent patients, and binge drinkers. Influential BI components include high-quality change plans and provider characteristics. Health professionals endorse BI and feel confident in delivering it, but training and support initiatives continue to show no significant effects on uptake, prompting calls for systematic approaches to implementing BI in health care

    Wafer-scale two-dimensional semiconductors from printed oxide skin of liquid metals

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    A variety of deposition methods for two-dimensional crystals have been demonstrated; however, their wafer-scale deposition remains a challenge. Here we introduce a technique for depositing and patterning of wafer-scale two-dimensional metal chalcogenide compounds by transforming the native interfacial metal oxide layer of low melting point metal precursors (group III and IV) in liquid form. In an oxygen-containing atmosphere, these metals establish an atomically thin oxide layer in a self-limiting reaction. The layer increases the wettability of the liquid metal placed on oxygen-terminated substrates, leaving the thin oxide layer behind. In the case of liquid gallium, the oxide skin attaches exclusively to a substrate and is then sulfurized via a relatively low temperature process. By controlling the surface chemistry of the substrate, we produce large area two-dimensional semiconducting GaS of unit cell thickness (∼1.5 nm). The presented deposition and patterning method offers great commercial potential for wafer-scale processes
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