1,720,956 research outputs found
p-Pheneylendiamine functionalized rGO/Si heterostructure Schottky junction for UV photodetectors
No full textIn this work, we report on p-Phenylenediamine (PPD) functionalized reduced graphene oxide (rG0)/Si hybrid-structure designed for UV photodetector applications (PD). The hybrid-structure was characterized by using Fourier Transform-infrared spectroscopy, X-ray photoelectron spectroscopy to confirm the formation of nano-hybrid structure and the experimental results confirmed the covalent bond between rGO and PPD. The diode parameters such as barrier height, series resistance, and ideality factor were estimated for both PPD functionalized rGO (PrGO)/Si and rGO/Si heterostructure by using I-V characteristics. The time-resolved photocurrent spectroscopy used to examine the photoresponse properties of both PrGO/Si and rGO/Si samples with UV light (lambda = 382 nm). The experimental results showed that PrGO/Si exhibited significant UV photoresponse than that of rGO/Si PD. The PrGO/Si heterostructure device exhibited photoresponsivity of 1.4 x 10(-3) A/W, which is 15 times higher than rGO/Si. The high photoresponse was attributed to the synergistic effects originated from the charge transfer between PPD and rGO. The results proved that PrGO is a promising material for high response photodetector applications.
Boron doped g-C3N4 quantum dots based highly sensitive surface acoustic wave NO2 sensor with faster gas kinetics under UV light illumination
No full textThe elegant two-dimensional (2D) graphitic carbon nitride (GCN) holds great promise in the detection of haz-ardous toxic gases especially NO2, for environmental protection and public health safety. However, the poor sensitivity and low surface area of bulk 2D GCN restrains its practical applicability of room temperature (RT) NO2 sensing. Herein, we present the fabrication of boron-doped GCN quantum dots (B@GCN QD) coated lan-gasite (LGS) based surface acoustic wave (SAW) sensor for the RT NO2 gas detection, and applied UV activation energy (365 nm) as an effective strategy to further enhance the NO2 sensing. Fascinatingly, under UV light, the B@GCN QD/LGS SAW sensor showed an enhanced gas sensing performance to the NO2 gas (500 ppb -50 ppm) with high sensitivity (Delta f=35.97 kHz/50 ppm), good selectivity, ultra-low detection limit (DL similar to 7.9 ppb), fast response/recovery times (35 s/43 s), excellent long-term stability as compared to dark condition. This could be attributed to the generation of abundant photoinduced charge carriers under UV activation, which leads to the significant enhancement in conductivity and enlarged mass loading effect, also, the device showed robust sensitivity responses to NO2 gas at various temperatures (RT-200 degrees C) and relative humidity (20-80%) conditions. Moreover, the effective doping of B to the GCN QD exhibited a typical p-type behavior which is good in agreement with density functional theory predictions that can induce structural defects, vacancies, and amine functional groups leading to a high specific surface area, which can remarkably enhance the sensitivity and selectivity of NO2 gas. This work may provide insights into the design and development of 2D GCN nanostructure-based SAW RT gas sensors for environmental monitoring.
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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