1,721,115 research outputs found
Fundamental links between shear transformation, fi relaxation, and string-like motion in metallic glasses
No full textPlastic deformation and relaxation dynamics are two major topics in glass physics. Secondary (fi) relaxation has been assumed to be a relevant plastic mechanism in amorphous solids, e.g., metallic glasses (MGs), at the macroscopic scale. However, due to the constraints of the time scale of traditional computer simulation, it is still an open question whether the correlation can be justified at the atomic level, or is it just a correlation in a mean-field sense? In this work, molecular dynamics simulations augmented with metadynamics are conducted to study the basic atomic rearrangement mechanism up to experimentally relevant timescales (up to milliseconds). We show that in a unique Al90Sm10 MG with pronounced fi relaxation, the atoms initiating the plastic deformation are exactly the ones apt to develop string-like cooperative motions, as expected from the perspective of fi relaxation. For a Y65Cu35MG without obvious fi relaxation, string-like motions are rarely observed in the deformation of participating atoms, although their atomic displacements are also aligned in a correlative manner. Therefore, our laboratory long-time-scale observation enables the in situ construction of a fundamental link among the versatile concepts of shear transformation, fi relaxation, and string-like motion in amorphous materials
Water isolation and protective performance of waterborne graphene-doped epoxy coating
No full textA graphene-epoxy resin was prepared by physical blending home-made aqueous dispersion of graphene and two-component waterborne epoxy resin. The dispersed graphene in aqueous solution was analyzed by scanning electron microscopy. The water isolation and corrosion resistance of the waterborne epoxy coating doped with 0.5% graphene (0.5%G-E44) in simulated seawater were studied by polarization curve measurement, electrochemical impedance spectroscopy (EIS), and neutral salt spray (NSS) test, and compared with that of untreated E44 epoxy coating. The results indicated that graphene is dispersed well in the solution and presents good water-isolating performance, which is overlapped layer by layer in the waterborne epoxy resin, forming a dense physical isolation layer and thus slowing down the diffusion rate of water molecules in the coating. Fick diffusion coefficients of E44 and 0.5%G-E44 immersed in simulated seawater at early stage are 5.56 * 10~(-9) cm~2/s and 1.61 * 10~(-11) cm~2/s, respectively. The protection performance of waterborne epoxy coating is obviously improved by adding grapheme, as shown by the decreasing of self-corrosion current density and the increasing of coating resistance and charge transfer resistance. The coating features a level and smooth surface after 200 h NSS test without distinct corrosion
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
sj-xlsx-1-hol-10.1177_09596836211066605 – Supplemental material for Spatiotemporal changes in early human land use during the Holocene throughout the Yangtze River Basin, China
No full textSupplemental material, sj-xlsx-1-hol-10.1177_09596836211066605 for Spatiotemporal changes in early human land use during the Holocene throughout the Yangtze River Basin, China by Jie Yu, Yanyan Yu, Haibin Wu, Wenchao Zhang and Hui Liu in The Holocene</p
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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