1,720,968 research outputs found
Flexible Electronics
No full textThe interest in flexible electronics is on the rise as it brings an added functionality and esthetic value in the unconventional interfaces, such as biomonitoring systems, wearables, flexible textiles, paper-based technologies, and many other curves of soft schemes, for which traditional electronics are not suitable. The demand in new flexible platforms turns to a pursuit for functional materials and technologies commonly compatible with a low temperature, high-throughput processing, and novel methods for device integration. A wide range of functional materials involving nanoparticles, composites, semiconductor and metallic nanowires, carbon nanomaterials, polymers, conductive inks, and different hybrid structures are particularly interesting. This book brings a comprehensive overview on the most important technology development in the field of flexible electronics
Non-catalytic growth of metal oxide nanowires : properties and growth mechanism investigations
Get PDFThis thesis is devoted to the non-catalytic syntheses of metal oxide nanowires (NWs), and investigations of their properties and growth mechanisms. Two different approaches were applied for the syntheses - metal resistive heating and vapor growth methods. The products were thoroughly characterized by electron microscopy, optical and X-ray characterization techniques. The synthesized NWs were examined for field emission (FE) and ultraviolet (UV) sensing applications.
The resistive heating of various metals was demonstrated to be an efficient, simple and rapid method for the synthesis of CuO, Fe2O3, V2O5 and ZnO NWs under ambient air conditions. Fe2O3 NW formation was detected after just 2 s of heating; other metal oxide NWs were grown after 10 s. The NW growth mechanism during metal oxidation was explained based on observations of ZnO and Fe2O3 NW growth. The mechanism is based on the diffusion of metal ions to the surface through grain boundaries and to the tip of the growing NW through defect diffusion and by surface diffusion. FE from NWs grown by the resistive heating method exibited promising results for applications in vacuum electronic devices. Cold electron FE measurements showed that CuO NWs have a very low threshold electric field of 4 V/µm at a current density of 0.01 mA/cm².
For the vapor growth of ZnO tetrapods (ZnO-Ts) a vertical flow reactor was designed and constructed. It was shown that the morphology of ZnO-Ts could be adjusted via the Zn vapor pressure in the reactor. The highest aspect ratio of ZnO-T legs was obtained at 700 °C, at a Zn partial pressure of 0.08 atm. ZnO-Ts demonstrated application possibilities for transparent and flexible UV sensors. Sensors based on ZnO-Ts showed a 45-fold current increase under UV irradiation with an intensity of 30 µW/cm² at a wavelength of 365 nm, and a response time of 0.9 s. The high performance of the device was explained by the multiple contact barriers
Multifunctional Nanomaterials for Energy Applications
No full textThe rapid growth of the world's population has significantly increased energy consumption and environmental impact. The transition from fossil fuels to sustainable energy sources that is needed for a sustainable future demands more efficient materials and improved technologies, but allows us to tackle this great and necessary challenge. This Special Issue highlights some of the latest energy advances in the field of materials, in particular low-dimensional materials, and nanostructured materials. Various topics related to synthesis and characterization methods, properties, and energy application uses are highlighted
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
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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