1,720,956 research outputs found
Effect of 600°C reversion treatment to reabsorb α’ forged components made of F51 DSS
No full textDuplex stainless steels encounter the precipitation of several secondary phases that are detrimental to both mechanical and corrosion properties when exposed to temperatures above 300°C. When embrittlement is caused by the α’ phase, heat treatment just above the miscibility gap responsible for α’ separation is sufficient to restore the lost properties, avoiding the most common solubilization at 1050°C. The aim of this study was to determine the optimal holding time for 600°C reversion treatment of 2205 DSS affected by α’. Optimization was performed by characterizing the material treated for different periods of time. To verify the soundness of this treatment, an analogous experimental campaign was conducted on the same material that was reverted at 550°C for different periods. From the research, the most effective holding time for 600°C reversion was found to be 2 h, as it gave the best results for elongation, corrosion rate, ductility, UTS, and Rp02. Lower times do not allow for complete recovery from embrittlement, whereas longer times cause the precipitation of detrimental secondary phases. In this study, conventional characterization techniques were coupled with double-loop electrochemical potentiodynamic reactivation to verify the reliability of this technique for the detection of detrimental secondary phases
Strategic approaches to enhance quenching and partitioning applicability: optimizing mechanical properties and microstructure of commercial low-silicon 20MnB5 steel
No full textQuenching and partitioning (QP) is a heat treatment designed to induce a multiphase microstructure composed of martensite and retained austenite. This treatment introduces high tensile properties in the material, coupled with enhanced ductility compared to traditional treatments. This enhancement arises from the strain-induced transformation of retained austenite into martensite when subjected to loads. Austenite stabilization at room temperature is achieved through carbon diffusion from martensite to austenite during partitioning. Therefore, the chemical composition of the alloy is typically tailored to promote this phenomenon. Silicon is added to suppress carbide precipitation, while manganese is added to enhance austenite stability. However, in this study, we focus on commercial low-silicon 20MnB5 steel. This grade is a low-alloyed steel commonly used in the heat-treated condition and is potentially influenced by the properties introduced through QP treatment. Multiple quenching and partitioning treatments are designed and executed to investigate the applicability of QP on 20MnB5 steel. Intercritical treatment strategies are employed to enhance the hardenability of the selected alloy, aiming to prevent bainite transformation and increase the effectiveness of quenching and partitioning, increasing the free carbon at disposal for partitioning. XRD analyses are conducted to identify retained austenite in the final specimen, quantify its amount, and observe its morphology and location. Optical microscopy (OM) and scanning electron microscopy (SEM) are used to characterize the introduced multiphase microstructure. Tensile tests are performed to assess the mechanical properties introduced by the treatment. In conclusion, the study demonstrates the applicability of intercritical quenching and partitioning (QP) treatments on 20MnB5 steel. However, in the observed conditions, the stabilization of a fraction of retained austenite is not correlated to the greatest increase in UE, leading to the conclusion that the control of the surrounding microstructure is the primary factor that influences the final properties of the material
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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