954 research outputs found

    Diamond growth in premixed propylene-oxygen flames

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    Diamond film growth in low-pressure premixed propylene/oxygen flames is demonstrated. Well-faceted films are grown at a pressure of 180 Torr and a fuel/oxygen ratio of 0.47. Using propylene as the fuel may greatly improve the economics of flame synthesis of diamond, since propylene is an order of magnitude cheaper than acetylene

    Diamond films from combustion of methyl acetylene and propadiene

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    To date diamond films grown with the combustion technique have used either acetylene or, rarely, ethylene as the fuel. However, there are barriers to large scale commercialization of the combustion technique using either fuel. For example, acetylene is relatively expensive and difficult to handle, while the use of ethylene gives relatively low growth rates. In this letter we propose replacing acetylene with MAPPTM gas, a commercial mixture of methyl acetylene and propadiene in liquefied petroleum gas (primarily propylene). MAPP gas is considerably cheaper, safer, and easier to handle than acetylene. Furthermore, the experiments described here suggest that MAPP gas flames are only slightly less efficient than acetylene flames at converting fuel carbon atoms into diamond

    Order Learning – An Overview

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    Toward a Human-Centered AI-assisted Colonoscopy System

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    AI-assisted colonoscopy has received lots of attention in the last decade. Several randomised clinical trials in the previous two years showed exciting results of the improving detection rate of polyps. However, current commercial AI-assisted colonoscopy systems focus on providing visual assistance for detecting polyps during colonoscopy. There is a lack of understanding of the needs of gastroenterologists and the usability issues of these systems. This paper aims to introduce the recent development and deployment of commercial AI-assisted colonoscopy systems to the HCI community, identify gaps between the expectation of the clinicians and the capabilities of the commercial systems, and highlight some unique challenges in Australia.Comment: 9 page

    Thermoelectric properties of graphene incorporated thermoelectric materials

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    Thermoelectric materials, which can change the waste heat into the usable electricity, are interested in various field of applications such as vehicle, ship, power plane, and so on. To enhance the thermoelectric properties, high electrical conductivity, high Seebeck coefficient, and low thermal conductivity should be conducted, however, the trade-off relation between electronic property and thermal property in terms of carrier concentration could be the bottle-neck on the enhancement of thermoelectric properties of the materials. In this presentation, we discuss with the graphene incorporation in the conventional thermoelectric materials, which could lead to independently control electric and thermal properties

    Quality of life in intermittent exotropia for Korean children and their parents

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    Background Patients with strabismus are more likely to have mental health problems, including high rates of depressive symptoms and social phobia. Intermittent exotropia (IXT) typically occurs in early childhood and is more common in Asian populations. We aim to assess the health-related quality of life (HRQOL) concerns in children with intermittent exotropia (IXT) using the Intermittent Exotropia Questionaire (IXTQ), and their associations with the clinical severity of IXT and the parents HRQOL concerns. Methods IXT, defined as both distance and near exodeviation ≥ 10 prism diopters were eligible for inclusion. The final IXTQ score is calculated using the mean score for all items, and ranges from 0 (worst HRQOL) to 100 (best HRQOL). The correlations of child IXTQ scores with their deviation angle and stereoacuity were measured, as were those with their parents IXTQ scores. Results One hundred twenty-two children with IXT (aged 5–17 years) and one parent for each child completed the child and parent IXTQ, respectively. The greatest HRQOL concern for each child with IXT and their parent was Worry about eyes (frequency 88%, score 35.0 ± 27.8). Lower child IXTQ scores were associated with a larger distance (r = 0.24, p = 0.007) and near deviation angle (r = 0.2, p = 0.026). It bothers me because I have to wait for my eyes to clear up and Waiting for their eyes to clear up were more common in children with a larger deviation angle (both p < 0.05). The parent IXTQ scores (52.1 ± 25.3) were lower than the child ones (79.7 ± 15.8) and showed a positive correlation with child IXTQ scores (r = 0.26, p = 0.004). Lower parent IXTQ scores were associated with poor distance stereoacuity (r = 0.23, p = 0.01). Conclusion The HRQOL of IXT children was positively related to that of their parents. A larger deviation angle and worse distance stereoacuity function may predict more-negative impacts on children and their parents, respectively.This research was supported by Basic Science Research Program through the National Research Foundation of Korea(NRF) grant funded by the Korea government(MSIT) (No. 2020R1C1C1010834)

    A carbon nanotubes-silicon nanoparticles network for high performance lithium rechargeable battery anodes

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    As an effort to address the chronic capacity fading of Si anodes and thus achieve their robust cycling performance, herein, we develop a unique electrode in which silicon nanoparticles are embedded in the carbon nanotubes network. Utilizing robust contacts between silicon nanoparticles and carbon nanotubes, the composite electrodes exhibit excellent electrochemical performance : 95.5% capacity retention after 140 cycles as well as rate capability such that at the C-rate increase from 0.1C to 1C to 10C, the specific capacities of 850, 698, and 312 mAh/g are obtained, respectively. The present investigation suggests a useful design principle for silicon as well as other high capacity alloying electrodes that undergo large volume expansions during battery operations.
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