1,720,962 research outputs found
The impact of ZnO nanotube on the performance of hybrid inorganic/organic light-emitting diode as a single-mode ring-core UV waveguide
No full textAfter a systematic survey in hybrid inorganic/organic light-emitting heterostructure devices based on ZnO in the last decay, in this novel work, the impact of the single-mode ring-core waveguide based on ZnO nanotube (NT)/MEH-PPV for ultraviolet organic light-emitting diode (UV-OLED) application has been carefully scrutinized for the first time. The proposed structure has been fabricated, simulated and compared with conventional ZnO nanorod (NR)/MEH-PPV structure. To synthesize ZnO NTs, the as-grown chemical bath deposited ZnO NRs have been etched in KCL solution in various molar (M) concentration, etching time and etching temperature. The optimized etching condition is obtained in 1 M concentration of KCL solution, 4 h etching time and 90 °C temperature. The structural properties (such as strain, stress and texture coefficient), electrical properties (such as band gap energy) and optical properties (such as Urbach energy, absorbance and photoluminescence spectra) of ZnO NTs have been investigated, systematically. In continue, hybrid UV-OLEDs have been fabricated based on ZnO NRs and ZnO NTs. According to the results, ZnO NT-based OLED depicts superior electrical and optical results including lower turn-on voltage (11.2 V < 15 V) and higher UV peak in electroluminescence spectra with respect to ZnO NR-based device. To acquire more enlightenment about UV emission mechanism, the proposed devices have been simulated through Silvaco TCAD and Lumerical FDTD software. The results from simulations illustrate great agreement with experimental results. Higher radiative recombination rate, higher Purcell factor and single-mode waveguiding effect of ring-core ZnO NT lead to major superiority of the ZnO NT-based UV-OLED fabricated and simulated in this work
Strategies for Advancing Near-Infrared Organic Light-Emitting Diodes: Innovations in Luminescent Materials, Device Architectures, Fabrication Methods, and Applications
No full textThis review focuses on recent advances in the efficient generation of near-infrared (NIR) light by organic light-emitting diodes (OLEDs). Novel NIR-emissive materials-encompassing various modern upconversion mechanisms-are integrated with device design with an overview of various OLED fabrication techniques, emphasizing the importance of thermal stability and the role of inks and solvents in achieving uniform luminescent films. The impact of these factors on device fabrication, achievable wavelength range, and overall OLED output characteristics is discussed, as well as emerging applications of NIR emission in medicine and security. Further, ideas and (likely) overlooked factors for enhancing NIR-OLED performance are presented. By combining materials and engineering-based strategies, a broader perspective and valuable insights into the design of high-performance NIR-OLEDs are offered
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
Plasmon enhanced fluorescence from meticulously positioned gold nanoparticles, deposited by ultra sonic spray coating on organic light emitting diodes
No full textEnhancement of the spontaneous emission of fluorophores aided by plasmonic nanoparticles (PNPs) prompts the growth of plasmonic organic light emitting diodes (OLEDs). Together with the spatial dependence of the fluorophore and PNPs on enhanced fluorescence, the surface coverage of the PNPs controls the charge transport in OLEDs. Hence, here, the spatial and surface coverage reliance of plasmonic gold nanoparticles is controlled by a roll-to-roll compatible ultrasonic spray coating technique. A 2-fold enhancement in the multi photon fluorescence is seen by two-photon fluorescence microscopy for a polystyrene sulfonate (PSS) stabilized gold nanoparticle located 10 nm away from the super yellow fluorophore. Fluorescence enhancement combined with ∼2% surface coverage of PNPs, provides a 33%, 20% and ∼40% increase in the electroluminescence, luminous efficacy and external quantum efficiency, respectively.sponsorship: Universiteit Hasselt|BOF18NI05status: Publishe
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
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