1,721,087 research outputs found
Reaction paths and efficiency of photocatalysis on TiO2 and of H2O2 photolysis in the degradation of 2-chlorophenol
No full textThe kinetics of 2-chlorophenol (2-CP) degradation and mineralization in the aqueous phase was investigated under irradiation at 254 nm, employing either photocatalysis in the presence of titanium dioxide, or hydrogen peroxide photolysis, to compare the efficiency of these photoinduced advanced oxidation techniques. Photocatalysis under 315-400 nm wavelength irradiation was also investigated. The concentration versus time profiles of the degradation intermediates catechol, chloro- and hydroxy-hydroquinone allowed the identification of the reaction paths prevailing under the different experimental conditions. Efficient C-Cl bond cleavage occurred as a consequence of direct light absorption by 2-CP, while hydroxyl radicals, photogenerated at the water-photocatalyst interface or during H2O2 photolysis, were the main oxidation agents, able to attack both 2-CP and its degradation intermediates. Highest degradation and mineralization efficiencies were achieved under H2O2 photolysis at 254 nm. (c) 2006 Elsevier B.V. All rights reserved
Kinetic analysis on the combined use of photocatalysis, H2O2 photolysis and sonolysis in the degradation of methyl tert-butyl ether
No full textPhotocatalysis on TiO2, with irradiation wavelength 254 nm or 315- 400 nm, and sonolysis at 20 kHz were employed, either separately or simultaneously, or in the presence of hydrogen peroxide, as advanced oxidation techniques in the degradation of methyl tert-butyl ether (MTBE) in water under atmospheric conditions. MTBE generally underwent degradation according to a first-order rate law. The prevailing reaction paths were identified by monitoring the time profile of the main reaction intermediates (acetone, tert-butyl formate and tert-butyl alcohol). Hydroxyl radicals, able to attack both MTBE and its degradation intermediates, played a central role in all degradation conditions. The highest degradation and mineralization efficiency, in terms of both treatment duration and energy consumption, was achieved under hydrogen peroxide photolysis at 254 nm
Assessing the Social Behavior of Unipolar Depressives: The Criteria for Typus Melancholicus
No full textAim: (a) To defi ne the nuclear characteristics of the melancholic type of personality (TM), that in European and
Japanese psychopathological tradition is considered the
model which most accurately describes the social behavior
of unipolar depressives, through clear, valid, and synthetic
criteria (criteria for TM = CTM); (b) to evaluate the diagnostic power, reliability, internal consistency, and other psychometric properties of these criteria.
Methods: Personality features of 115 unipolar depressives
consecutively admitted to 2 psychiatric facilities were assessed with the CTM and with the Kasahara Scale (KS).
Four further unipolar depressives were assessed with the CTM by 13 different raters (11 CTM-naive and 2 experienced).
Results: The CTM have shown high reliability and internal consistency. They were also highly concordant with the KS scores. Conclusions: The CTM can discriminate between TMs and non-TMs and suggests that the TM kind of personality is not a dimensional concept but a coherent structure in which one feature entails the presence of all the others
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
Typus Melancholicus: personality Structure and the Characteristics of Major Unipolar Depressive Episode.
No full textPhysical exercise to prevent multifactorial diseases: A warning written in our genes?
No full textThe human genome has about forty thousand genes and has been subject to strong selective pressure in various periods and different geographical areas. Various evidence sustains the hypothesis that the widespread nature of multifactor diseases is partly due to modified life-styles (reduced physical activity, over-eating) and partly to genetic inheritance selected over thousands of years for life-styles that persisted almost up to the start of the twentieth century. Physical activity could therefore be a natural remedy for recovering part of the imbalance caused by modern life-styles in bodies "born to run" and fed parsimoniously. In order to prescribe it as a cure, more research is necessary into the effects of physical activity on the body at molecular level and into individual predispositions to be used in targeted prevention programmes
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
- …
