1,720,987 research outputs found
Perpendicularly magnetized synthetic antiferromagnets for flexible spintronic and biomedical applications
Full text linkAntiferromagnetici sintetici (SAF) costituiti da due strati ferromagnetici separati da un sottile strato metallico non magnetico hanno recentemente suscitato un rinnovato interesse come potenziali candidati per una serie di applicazioni innovative e avanzate nell’ambito della spintronica e della biotecnologia. I SAF sono componenti chiave nei dispositivi spintronici e una significativa attenzione è stata recentemente prestata alla preparazione di tali sistemi su substrati flessibili in virtù dei significativi vantaggi che offrono rispetto a dispositivi fabbricati su substrati rigidi convenzionali, come la capacità di piegare e regolare la forma del substrato, un minor peso e costi contenuti. Sebbene il progresso e lo sviluppo di sistemi spintronici con anisotropia magnetica longitudinale su substrati non planari sia stato notevole nel corso degli ultimi anni, eterostrutture magneto-resistive flessibili con anisotropia magnetica perpendicolare (PMA) sono piuttosto inesplorate nonostante consentano funzionalità aggiuntive e prestazioni migliorate. D'altra parte, per applicazioni diagnostiche e terapeutiche, microdischi SAF con magnetizzazione perpendicolare preparati con approcci litografici top-down sono stati recentemente proposti come valida alternativa alle più studiate particelle superparamagnetiche sintetizzate per via chimica in quanto soddisfano tutti i criteri chiave richiesti per applicazioni biomedicali, consentendo al contempo un significativo grado di controllo e modulazione delle proprietà magnetiche.
In questo contesto, la tesi si propone di sviluppare e studiare dispositivi magneto-resistivi su substrati flessibili e microdischi per applicazioni biomedicali basati su SAF a film sottile con PMA. L'attenzione si è concentrata su sistemi basati su Co/Pd e Co/Ni in virtù dell’elevata anisotropia magnetica (~106 J/m3) e della possibilità di regolare in maniera fine le proprietà magnetiche variando lo spessore dei singoli strati e il numero di ripetizioni N del doppio strato di Co/Pd(Ni). In particolare, multistrato flessibili con struttura spin-valve e magnetoresistenza gigante, costituiti da un free layer di [Co/Pd(Ni)]N e da un reference layer SAF con struttura [Co/Pd(Ni)]N/Ru/[Co/Pd(Ni)]N separati da uno strato di Cu, sono stati preparati sia mediante deposizione diretta su substrati flessibili che attraverso l’utilizzo di strategie transfer-and-bonding di tipo wet e dry. Sono state inoltre eseguite misurazioni in condizioni di flessione per indagare la robustezza delle spin-valve flessibili e la possibilità della loro integrazione su superfici curve. Film SAF ottimizzati sono stati infine impiegati per la preparazione di multistrato a film sottile costituiti da ripetizioni multiple di singole unità SAF con struttura [Co/Pd]N/Ru/[Co/Pd]N e anisotropia magnetica perpendicolare allo scopo di fabbricare microdischi SAF free-standing mediante processi litografici.Although discovered about three decades ago, the peculiar properties of synthetic antiferromagnetic (SAF) thin films consisting of two ferromagnetic layers separated by a non-magnetic metal spacer have recently revived a renewed interest as potential candidates for a number of innovative and advanced applications including spintronics and biotechnology. SAFs are key component in spintronic devices and a significant attention has been recently paid on the preparation of such devises on flexible substrates, which provide wide advantages over their conventional rigid-substrate counterparts, such as the ability to bend and adjust the shape of a device, a light-weight and low costs. While the progress and development of systems with longitudinal magnetic anisotropy on non-planar substrates has been remarkable over the last few years, flexible magneto-resistive heterostructures with perpendicular magnetic anisotropy (PMA) are rather unexplored despite they allow for additional functionality and improved performance. On the other hand, for diagnostic and therapeutic applications, perpendicular magnetized SAF microdisks prepared by top-down lithographic approaches have been recently proposed as a valid alternative to the most investigated superparamagnetic particles synthetized by chemical routes as they fulfill all the key criteria required for biomedical applications while allowing a significant degree of control and tunability of the magnetic properties.
Within this context, this thesis aims at developing and studying magneto-resistive spintronic devices on flexible substrates and microdiscs for biomedical applications based on SAF thin film stacks with PMA. The focus was on Co/Pd- and Co/Ni-based systems due to their strong PMA (~106 J/m3) and the possibility to finely tune their magnetic properties by varying the thickness of the individual layers and the number of repetitions N of the Co/Pd(Ni) bilayer. In particular, flexible Co/Pd(Ni)-based giant magnetoresistance spin-valve thin film stacks consisting of a [Co/Pd(Ni)]N free layer and a fully compensated [Co/Pd(Ni)]N/Ru/[Co/Pd(Ni)]N synthetic antiferromagnet reference electrode separated by a Cu spacer, were prepared by direct deposition on flexible substrates and by exploiting both wet and dry-etching transfer-and-bonding approaches. Measurements under bending conditions were also performed to investigate the robustness of the flexible spin-valves and the possibility for their integration on curved surfaces. The optimized SAF stacks were also used for the preparation of thin fil stacks consisting of multiple repeats of single [Co/Pd]N/Ru/[Co/Pd]N SAF units with perpendicular magnetic anisotropy with the aim to fabricate free-standing SAF microdisks by using lithographic processes
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
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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