1,720,957 research outputs found
The Wet Corrosion of Molybdenum Thin Film - Part IV: The Effect of Nitriding
No full textA considerable number of detailed investigations have been carried out on the deposition and characterisation of molybdenum and molybdenum-titanium-nitride films by employing a variety of techniques. However, very little is currently known about the effect of composition (N-2/Ar flow rate) on the corrosion properties of MoN and MoTiN thin films for aggressive ambient conditions. In this work, the electrochemical and corrosion behaviour of MoN and MoTiN thin films, produced by Physical Vapour Deposition (PVD) with different N2/Ar flow rates, has been investigated by Electrochemical Impedance Spectroscopy (EIS) in aerated alkaline chloride solution and compared with the behaviour of pure molybdenum in the same environment. Results obtained indicate that increasing nitrogen content in the film leads to a beneficial effect on the corrosion resistance, but results in decreased electrical conductivity of the film that may limit their application as back contact in photovoltaic modules
Selected Cr(VI) replacement options for aluminum alloys: A literature survey
No full textThere is a significant move away from the use of hexavalent chromium, Cr(VI), which is a mature, trusted, and relatively inexpensive treatment that has been used for many years by industry to reduce corrosion. Although Cr(VI) is effective at reducing corrosion, it poses a substantial health hazard. While there is a need to define a process that will be able to replace Cr(VI), the process must be able to provide the same level of corrosion protection currently provided by hexavalent treatments. In addition, it needs to do this without the associated environmental problems. This paper focuses mainly, but not exclusively, on the trivalent chromium pretreatment (TCP) and its commercially available variants. The TCP was developed by the Naval Air Systems Command (NAVAIR) and is used by the US military. The rationale for the focus of this paper is that in the near term, the aeronautics industry needs to move away from Cr(VI) towards a more benign commercially available chemical treatment that can help protect the aluminum alloys used by that industry. TCPs are currently available commercially and have undergone numerous tests by multiple organizations to establish their effectiveness in reducing corrosion of both bare and painted aluminum alloys
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
An overview of the critical technological issues relevant to the joining of light alloys for aerospace applications
No full textFriction Stir Welding (FSW) is a relatively new technology that was developed at The Welding Institute (TWI) in 1991. It is a solid phase process that operates at temperatures below the melting point of the materials being joined. All aluminium alloys can be welded, including some that cannot be joined by conventional fusion techniques such as Tungsten Inert Gas (TIG). Compared to fusion welding, the relatively low temperatures involved in FSW reduce thermal stresses and distortion. There is substantial potential for employing FSW during the fabrication of various components within the aerospace, shipbuilding, and automotive industries. As these welds may experience diverse aggressive environments, it is crucial to understand the degradation characteristics. This paper looks at some of the key technological issues relevant to the joining of light alloys
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
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
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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