1,720,965 research outputs found
Surface characterisation of contact materials for thin film CdTe solar cells
No full textThe deposition of tellurium onto the low index faces of copper single crystals induces a range of structures such as the (2√3×2√3)R30° surface substitutional alloy on the Cu(111) surface. These structures have been studied using a combination of scanning tunnelling microscopy (STM), low energy electron diffraction (LEED), X-ray photoemission (XPS) and ultraviolet photoemission (UPS).
The deposition of tellurium on to the Cu(111) surface produced several structures including (2√3×2√3)R30° phase for a coverage of 0.17ML, For a coverage of 0.33ML a (√3×√3)R30° surface alloy was found. For coverages greater than 0.66ML a bulk alloy was formed which is consistent with the Cu3Te2 phase. The deposition of tellurium onto the Cu(110) surface produced a c(2×2) structure for a coverage of 0.5ML. Further deposition causes uniaxial compression of the over-layer as indicated by the LEED patterns. STM of this surface revealed two hexagonal domains rotated 30° with respect to each other.
The deposition of tellurium on to the Cu(100) surface produced a p(2×2) over−layer for a coverage of 0.25ML. Further deposition lead to a series of coincidence lattices showing co-existing structures including split c(2×2) spots in the LEED pattern. A heavily streaked split c(2×2) LEED pattern was observed for tellurium coverages over 1ML dosage where STM images revealed a heavily striped surface with two domains perpendicular to each other. The larger structures observed suggest 3D growth of these stripes. On all 3 surfaces the work function was found to increase upon tellurium deposition.
The electronic structure of indium oxide thin films was investigated after different treatments in ultra high vacuum using XPS and UPS. The (111) surface was investigated using a combination of hard and soft X-rays showing the lower portion of the valence band to be dominated by oxygen orbitals while the higher portion of the valence band indium orbitals. The valence band was then probed and the work function measured after different annealing treatments. For all 3 samples, (111) (110) and (100) the work function was found to increase when annealing in oxygen when compared to annealing in vacuum. This is attributed to the movement of the Fermi level as the carrier concentration at the surface is altered. The lowering of observed gap states when annealing in oxygen also suggests they may originate from oxygen vacancies within the surface
Surface characterisation of contact materials for thin film CdTe solar cells
No full textThe deposition of tellurium onto the low index faces of copper single crystals induces a range of structures such as the (2√3×2√3)R30° surface substitutional alloy on the Cu(111) surface. These structures have been studied using a combination of scanning tunnelling microscopy (STM), low energy electron diffraction (LEED), X-ray photoemission (XPS) and ultraviolet photoemission (UPS).
The deposition of tellurium on to the Cu(111) surface produced several structures including (2√3×2√3)R30° phase for a coverage of 0.17ML, For a coverage of 0.33ML a (√3×√3)R30° surface alloy was found. For coverages greater than 0.66ML a bulk alloy was formed which is consistent with the Cu3Te2 phase. The deposition of tellurium onto the Cu(110) surface produced a c(2×2) structure for a coverage of 0.5ML. Further deposition causes uniaxial compression of the over-layer as indicated by the LEED patterns. STM of this surface revealed two hexagonal domains rotated 30° with respect to each other.
The deposition of tellurium on to the Cu(100) surface produced a p(2×2) over−layer for a coverage of 0.25ML. Further deposition lead to a series of coincidence lattices showing co-existing structures including split c(2×2) spots in the LEED pattern. A heavily streaked split c(2×2) LEED pattern was observed for tellurium coverages over 1ML dosage where STM images revealed a heavily striped surface with two domains perpendicular to each other. The larger structures observed suggest 3D growth of these stripes. On all 3 surfaces the work function was found to increase upon tellurium deposition.
The electronic structure of indium oxide thin films was investigated after different treatments in ultra high vacuum using XPS and UPS. The (111) surface was investigated using a combination of hard and soft X-rays showing the lower portion of the valence band to be dominated by oxygen orbitals while the higher portion of the valence band indium orbitals. The valence band was then probed and the work function measured after different annealing treatments. For all 3 samples, (111) (110) and (100) the work function was found to increase when annealing in oxygen when compared to annealing in vacuum. This is attributed to the movement of the Fermi level as the carrier concentration at the surface is altered. The lowering of observed gap states when annealing in oxygen also suggests they may originate from oxygen vacancies within the surface
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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