1,720,982 research outputs found
Mobility of magmas within the Earth: Insights from the elasticity and transport properties of hydrous albitic melts
No full text<p>Results from first-principles molecular dynamics simulations of anhydrous and hydrous albitic melts.</p>
Viscosity Measurements at High Pressures: A Critical Appraisal of Corrections to Stokes' Law
No full text<p>Included are central data and codes for the manuscript "Viscosity Measurements at High Pressures: A Critical Appraisal of Corrections to Stokes' Law", submitted for review.</p>
Viscosity Measurements at High Pressures: A Critical Appraisal of Corrections to Stokes' Law
No full text<p>Included are central data and codes for the manuscript "Viscosity Measurements at High Pressures: A Critical Appraisal of Corrections to Stokes' Law", published May 2, 2024.</p>
<p>Reference for full article:</p>
<p>Ashley, A.W., Mookherjee, M., Xu, M., Yu, T., Manthilake, G., & Wang, Y. (2024). Viscosity measurements at high pressures: A critical appraisal of corrections to Stokes' Law. Journal of Geophysical Research: Solid Earth, 129, e2023JB028489. https://doi.org/10.1029/2023JB028489</p>
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Variations on the Author
Get PDF“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
A high-temperature Fourier transform infrared study of the interlayer and Si�O-stretching region in phengite-2 M 1
No full textA natural phengite-2M1 of composition (Kn95Na05)(AlnFen14Mg 10)2 (Si?25Al0 (OH196Fo04) [a 5.2173(1) A.b 9.0493(2) A, c 19.989 (1) A and B 95.734(4) ] was studied using in situ high-temperature FTIR. Correlations to structural changes were made using previously-reported neutron diffraction data from the same sample. Correlations have been made between the microscopic atomic displacements (arising from thermal effects) and analogous macroscopic properties, such as bond strain and ditrigonal distortions. Spectra were collected in the far-infrared region to study the behaviour of the interlayer (K ) cation and also in the mid-infrared region to distinguish the Si O stretching modes. We found anisotropic thermal expansion of the interlayer site. The K-O bond length is divided into K Oouter and K-Oinner and the K O bond length is correlated with the far-infrared spectra. The thermal dependence of the correlation between K O bond length and corresponding far-infrared stretching frequency is different from the effect of the chemical composition. We also found that the K O bond strain could be successfully resolved into the sum of inner strain and lattice strain. The Si O stretching mode. obtained from the mid-infrared measurements, showed only weak changes. However, the neutron refinement data showed different thermal behaviour for distinct crystallographie T-sites
High-pressure phase of brucite stable at Earth's mantle transition zone and lower mantle conditions
Get PDFWe investigate the high-pressure phase diagram of the hydrous mineral brucite, Mg(OH)2, using structure search algorithms and ab initio simulations. We predict a high-pressure phase stable at pressure and temperature conditions found in cold subducting slabs in Earth’s mantle transition zone and lower mantle. This prediction implies that brucite can play a much more important role in water transport and storage in Earth’s interior than hitherto thought. The predicted high-pressure phase, stable in calculations between 20 and 35 GPa and up to 800 K, features MgO6 octahedral units arranged in the anatase–TiO2 structure. Our findings suggest that brucite will transform from a layered to a compact 3D network structure before eventual decomposition into periclase and ice. We show that the high-pressure phase has unique spectroscopic fingerprints that should allow for straightforward detection in experiments. The phase also has distinct elastic properties that might make its direct detection in the deep Earth possible with geophysical methods
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe 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
Get PDFWe 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
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