1,720,972 research outputs found
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Stable Purely Organic Radical Thin Films and Interfaces for Applications
No full textDer Schwerpunkt dieser Arbeit liegt auf rein organischen Radikalen, die aufgrund ihrer
strukturellen Vielfalt, ihrer Funktionalität und ihres intrinsischen magnetischen Moments
eine spannende Spielwiese für Anwendungen in der Spintronik darstellen. Die ausgewählten Radikale wurden aufgedampft und durch organische Molekularstrahlabscheidung auf
unterschiedliche Substraten abgeschieden, anschießend wurden die Proben mit Hilfe von
kombinierten Methoden wie die Röntgenphotoelektronenspektroskopie, Röntgen-NahkantenAbsorptions-Spektroskopie und Rasterelektronenmikroskopie charakterisiert.
Der erste Teil der Arbeit ist dem Dicyano-Tetrazolinyl-Radikal gewidmet, das eine starke
Tendenz zur Inselbildung aufweist, wenn es aufgedampft und auf verschiedenen Substraten
abgeschieden wird. Das Radikal bildet Cluster mit einer Nanonadel-Morphologie auf der
SiO2/Si(111)-Oberfläche und Nanostäbchen auf Gold. Die Untersuchung der Radikale auf
einem hybriden Substrat, bestehend aus SiO2/Si(111) und polykristallinem Gold, ermöglichte die Untersuchung des Einflusses der Wechselwirkung zwischen Radikal und Substrat
und der Art des Substrats auf die Morphologie der Radikale. Ein besseres Verständnis des
Wachstumsprozesses an der hybriden Grenzfläche kann, bei der Entwicklung einer Strategie
zur Herstellung eindimensionaler Nanostrukturen mit spezifischer Morphologie als integraler
Bestandteil von Nanobauteilen, helfen.
Der zweite Teil der Arbeit ist dem Radikalderivat Blatter gewidmet. Die Stabilität von Blatterpyr- und diBlatter-Filmen wird unter Luftexposition untersucht. Die überlegene Luftstabilität
von Blatter-pyr mit einem Radikalzentrum im Vergleich zu diBlatter, das zwei Radikalzentren
aufweist, lässt sich durch die Wasserbeständigkeit der Blatter-pyr-Moleküle in den Filmen
erklären. Im folgenden Teil werden die elektronischen und magnetischen Eigenschaften der
Blatter-pyr/Co-Hybrid-Grenzfläche beschrieben. Hybridisierung und Ladungstransfer an der
Grenzfläche führen zum Verlust der radikalen Funktionalität der Filmmoleküle und zur
Unterdrückung des magnetischen Moments der an die organischen Moleküle gebundenen
Co-Atome. Die Ergebnisse zeigen, dass die Interaktion an der Grenzfläche die lokalen chemischen und magnetischen Eigenschaften der hybriden Grenzfläche bestimmt und als ein
leistungsfähiger Ansatz zur Manipulation und Kontrolle des Spintransports in zukünftigen
molekularen spintronischen Bauelementen angesehen werden kann.The spotlight of this work is on purely organic radicals, which built an exciting playground
for spintronic applications due to their structural diversity, functionality, and intrinsic magnetic moment. The selected radicals were evaporated and deposited on various substrates
by organic molecular beam deposition and characterized by joined methods such as X-ray
photoelectron spectroscopy, near-edge X-ray fine structure and scanning electron microscopy.
The first part of the thesis is dedicated to the dicyano tetrazolinyl radical that shows a strong
tendency toward island formation when evaporated and deposited on different substrates
under the presented preparation conditions. The radical forms assemblies with a nanoneedle
morphology on SiO2/Si(111) surface and “monoliths” on gold. The study of radical assemblies on the hybrid substrate, consisting of SiO2/Si(111) and polycrystalline gold, allowed to
investigate the influence of radical-substrate interaction and substrate nature on the assembly
morphology. Improved understanding of the growth process on the hybrid interface can aid
in the development of a strategy to achieving nanostructures with specific morphology as an
integral component of nanodevices.
The second part of the work is dedicated to the Blatter radical derivatives. The stability of
Blatter-pyr and diBlatter films is probed under air exposure. The superior air stability of
Blatter-pyr with one radical site in comparison to diBlatter that poses two radical centers can
be explained by water-resistance of Blatter-pyr molecules in films. The following part captures
the electronic and magnetic properties of the Blatter-pyr/Co hybrid interface. Hybridization
and charge transfer at the interface result in loss of the radical functionality of film molecules
and the suppression of the magnetic moment of Co atoms bonded to the organic molecules.
The results demonstrate that interface interaction defines the hybrid interface’s local chemical
and magnetic properties and can be viewed as a powerful approach for manipulating and
controlling spin transport in future molecular-based spintronic devices
Substrate-induced effects in thin films of a potential magnet composed of metal-free organic radicals deposited on Si(111)
No full text
Variations on the Author
No full text“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
No full textWe 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
No full textWe 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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