1,721,414 research outputs found
Joseph R. Burch Korean War collection [DIGITAL CONTENT]
No full textThis collection contains an oral history interview with Joseph R. Burch from August 28, 2009, as well as documents pertinent to his military service
sj-pdf-1-hpp-10.1177_15248399221128609 – Supplemental material for WiFi in the Woods
No full textSupplemental material, sj-pdf-1-hpp-10.1177_15248399221128609 for WiFi in the Woods by Shanaé R. Burch in Health Promotion Practice</p
Kinetic and mechanism of the reduction of NO by n-octane over Pt/Al2O3 under lean burn conditions
No full textThe effect of temperature, contact time, and reactant concentration on the reduction of NO by n-C8H18 over Pt/Al2O3 under oxidising conditions was investigated. The oxidation of n-C8H18 appears to be delicately balanced between two kinetic regimes. At low [C8H18]/[O2] the coverage of oxygen on the Pt surface is high, while that of carbonaceous species is negligible, resulting in hydrocarbon oxidation being inhibited by oxygen and in the oxidation of NO to NO2. At higher [C8H18]/[O2] the surface is saturated with carbonaceous species, while the coverage of oxygen is negligible, resulting in hydrocarbon oxidation being zero order in hydrocarbon concentration and in no NO2 formation being observed. The state of the Pt surface affects the mechanism of NOx reduction. Thus, NOx reduction via dissociation of NO on the Pt surface is favoured by a high coverage of carbonaceous species, while a high coverage of oxygen favours NOx reduction by reaction between n-C8H18-derived species and spilt-over NO2 on the Al2O3 support and/or metal-support interface. Separate kinetic models capable of fitting the data in these two regions have been developed
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
Particle size and support effects on the activity and deactivation of Pt-based catalysts for the reduction of NO by n-octane under lean-burn conditions
No full textVery high and stable activity for the reduction of NO by n-octane under lean-burn conditions may be achieved at temperatures as low as 180 degrees C by the use of supported Pt catalysts, providing the catalyst is clean and is comprised of large Pt particles
A method for obtaining stable, high activity for NOx reduction at low temperatures
No full textVery high and stable low temperature activity for the reduction of NO by n-octane on a 0.3 mass% Pt/Al2O3 catalyst operating under lean burn conditions may be achieved by secondary injection of micropulses of clean-burning thermal promoters into the gas stream
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
An investigation into the reactivity, deactivation, and in situ regeneration of Pt-based catalysts for the selective reduction of NOx under lean burn conditions
No full textThe activity and deactivation characteristics of Pt-based lean burn De-NOx catalysts have been investigated and the relationships between temperature, nature of reductant (n-octane) and NO2 concentrations, and the mechanism(s) of deactivation have been examined. The effects of Pt loading and particle size on the activity and deactivation have also been studied. The results show that deactivation of the catalyst is due to site blocking via an unidentified carbonaceous deposit and that the initial surface state of the Pt is crucial. In all cases clean Pt surfaces were found to display an initial period of surprisingly high activity prior to deactivation, the rate of which was inversely related to reaction temperature. Deactivation is proposed to arise from a combination of factors which inhibit adsorption and reaction of n-octane, due to encroachment onto the Pt surface of hydrocarbonaceous species accumulating initially on the support in the vicinity of the Pt/support interface. It is possible that these carbon-containing deposits comprise some form of organonitrogen species. The loss of activity due to this gradual encroachment results in a reduction in the temperature of the Pt particles, leading to a further decrease in reaction and/or desorption rates, and rapid deactivation then ensues. The use of higher Pt loadings leads to enhanced activity at lower temperatures and increased tolerance to the deactivating effects of surface deposition. Catalyst activity and tolerance to deactivation were further enhanced by controlled sintering, which, within certain limits, resulted in excellent, stable low-temperature De-NOx activity. The divergent activity of SiO2-, Al2O3-, and ZrO2-based catalysts reflects support effect contributions, with the former displaying poor low temperature activity and rapid deactivation while the latter supports, particularly ZrO2, exhibited high De-NOx activity at lower temperatures without deactivation. The use of temperature "spiking" and micropulse injection techniques facilitated regeneration of the full De-NOx activity. In particular, the use of micropulse injections of CH3OH into the n-C8H18-O2-NO reaction completely circumvented deactivation and demonstrated the potential for obtaining very high NOx conversions at low temperatures
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
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