1,720,966 research outputs found
Mechanism Study of Photocatalytic Degradation of Gaseous Toluene on TiO2 with Weak-Bond Adsorption Analysis Using In Situ Far Infrared Spectroscopy
Full text linkThe development of far infrared spectroscopy offers a powerful method for comprehensive study in adsorption structure and photocatalytic degradation mechanism of photocatalysis. This study presented an improved in situ diffuse reflectance infrared Fourier transform spectroscopy technique in far infrared region for investigation of weak-bond adsorption and photocatalytic degradation of gaseous toluene on the surface of TiO2. It was found that toluene tends to be adsorbed on the hydroxyl group via three possible sites, the ortho-, meta-, and para-adsorption site, instead of ipso-structure. The methyl group of toluene is consumed first during the process of toluene photocatalytic degradation. Based on these, a reaction route for the photocatalytic degradation of gaseous toluene on TiO2 surface was proposed
Analysis of structural changes at interfaces of dental tissues by EDIXS and FTIR
Full text linkFil: Sánchez, Héctor Jorge. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Sánchez, Héctor Jorge. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Leani, Juan Jose. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Leani, Juan Jose. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Robledo, José Ignacio. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Grenón, Miriam Silvina. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Periodoncia A; Argentina.Fil: Marcelli, Augusto Claudio. Laboratori Nazionali di Frascati; Italia.Fil: Migliori, Alessandro. International Atomic Energy Agency; Austria.Fil: Yuying Liu, Huijuan Wang. National Synchrotron Radiation Laboratory; China.Fil: Qi, Zeming, Huijuan Wang. National Synchrotron Radiation Laboratory; China.Participación en calidad de co-autora del trabajo: ?Analysis of structural changes at interfaces of dental tissues by EDIXS and FTIR?, H.J. Sánchez, J.J. Leani, J.I. Robledo, M. Grenón, A. Marcelli, A. Migliori, W. Yuying and Zeming Qi, EUROPEAN CONFERENCE ON X-RAY SPECTROMETRY (EXRS 2022), 2022, Brudge, BelgiumFil: Sánchez, Héctor Jorge. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Sánchez, Héctor Jorge. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Leani, Juan Jose. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina.Fil: Leani, Juan Jose. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Robledo, José Ignacio. Consejo Nacional de Investigaciones y Técnicas. Instituto de Física Enrique Gaviola; Argentina.Fil: Grenón, Miriam Silvina. Universidad Nacional de Córdoba. Facultad de Odontología. Cátedra de Periodoncia A; Argentina.Fil: Marcelli, Augusto Claudio. Laboratori Nazionali di Frascati; Italia.Fil: Migliori, Alessandro. International Atomic Energy Agency; Austria.Fil: Yuying Liu, Huijuan Wang. National Synchrotron Radiation Laboratory; China.Fil: Qi, Zeming, Huijuan Wang. National Synchrotron Radiation Laboratory; China.Odontología, Medicina y Cirugía Ora
DRIFTS Evidence for Facet-Dependent Adsorption of Gaseous Toluene on TiO2 with Relative Photocatalytic Properties
Full text linkEffective adsorption is of great importance to the photocatalytic degradation of volatile organic compounds. Herein, we succeeded in the preparation of anatase TiO2 with clean dominant {001} and {101} facets. By using in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) equipped with a homemade reaction system and a coupling gas-dosing system, we found that TiO2 with dominant {001} facets exhibits higher toluene adsorption capacity than TiO2 with dominant {101} facets, which may be attributed to the different number of unsaturated 5c-Ti capable of forming the main active adsorption sites (terminal Ti-OH species). TiO2 with dominant {001} facets shows a significantly high photocatalytic degradation performance, with its degradation rate being 6 times higher than that of dominant {101} facets. Combined with simulation results, it is suggested that the synergetic effects of the formation of specific active adsorption sites, the low adsorption energy for toluene, and preservation of the free molecularly adsorbed water on the surface promote the degradation of gaseous toluene on the dominant {001} facets. This study exemplifies that the facet-dependent adsorption of volatile organic compounds is one of the most important factors to effectively engineer photocatalysts for air purification
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
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
Effect of surface modification with H2S and NH3 on TiO2 for adsorption and photocatalytic degradation of gaseous toluene
No full textThis study investigates the effects of surface modification with H2S and NH3 respectively on the photocatalytic activity of TiO2 for toluene degradation. Surface modification with H2S was observed to enhance the adsorption of toluene and promote the degradation rate at the start of photocatalytic degradation, while that with NH3 inhibited the adsorption of toluene but enhanced the photocatalytic activity for the toluene degradation. By a combination of in situ DRIFTS and other characterization methods, the adsorption mechanism and relationship between surface structure and photocatalytic activity were proposed. For TiO2-H2S, the sulfhydryl group, which is formed from the dissociation of H2S molecules, could easily interact with toluene. The low photocatalytic activity may be caused by the inhibition of the regeneration of surface hydroxyl groups, poor generation of O2(-center dot) radicals and accumulation of highly stable intermediates. For TiO2-NH3, steric hindrance serves as interference to the adsorption of toluene, while the abundant surface hydroxyl groups are possibly conducive to the degradation of toluene. (C) 2015 Elsevier B.V. All rights reserved
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
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