1,720,963 research outputs found
Nanoconfined 2LiBH4eMgH2eTiCl3 in carbon aerogel scaffold for reversible hydrogen storage
Get PDFNanoconfinement of 2LiBH4–MgH2–TiCl3 in resorcinol–formaldehyde carbon aerogel scaffold (RF–CAS) for reversible hydrogen storage applications is proposed. RF–CAS is encapsulated with approximately 1.6 wt. % TiCl3 by solution impregnation technique, and it is further nanoconfined with bulk 2LiBH4–MgH2 via melt infiltration. Faster dehydrogenation kinetics is obtained after TiCl3 impregnation, for example, nanoconfined 2LiBH4–MgH2–TiCl3 requires ∼1 and 4.5 h, respectively, to release 95% of the total hydrogen content during the 1st and 2nd cycles, while nanoconfined 2LiBH4–MgH2 (∼2.5 and 7 h, respectively) and bulk material (∼23 and 22 h, respectively) take considerably longer. Moreover, 95–98.6% of the theoretical H2 storage capacity (3.6–3.75 wt. % H2) is reproduced after four hydrogen release and uptake cycles of the nanoconfined 2LiBH4–MgH2–TiCl3. The reversibility of this hydrogen storage material is confirmed by the formation of LiBH4 and MgH2 after rehydrogenation using FTIR and SR-PXD techniques, respectively.Fil: Gosalawit Utke, Rapee. Helmholtz-Zentrum Geesthacht; Alemania. Suranaree University of Technology; TailandiaFil: Milanese, Chiara. Universita degli Studi di Pavia; ItaliaFil: Javadian, Payam. University Aarhus; DinamarcaFil: Jepsen, Julian. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Laipple, Daniel. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Karmi, Fahim. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Puszkiel, Julián Atilio. Helmholtz-Zentrum Geesthacht; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Jensen, Torben. University Aarhus; DinamarcaFil: Marini, Amedeo. Universita degli Studi di Pavia; ItaliaFil: Klassen, Thomas. Helmholtz-Zentrum Geesthacht; AlemaniaFil: Dornheim, Martin. Helmholtz-Zentrum Geesthacht; Alemani
2LiBH4–MgH2–0.13TiCl4 confined in nanoporous structure of carbon aerogel scaffold for reversible hydrogen storage
Get PDFThe investigations based on kinetic improvement and reaction mechanisms during melt infiltration, dehydrogenation, and rehydrogenation of nanoconfined 2LiBH4-MgH2-0.13TiCl4 in carbon aerogel scaffold (CAS) are proposed. It is found that TiCl4 and LiBH4 are successfully nanoconfined in CAS, while MgH2 proceeds partially. In the same temperature (25-500ºC) and time (0?5 h at constant temperature) ranges nanoconfined 2LiBH4-MgH2-0.13TiCl4 dehydrogenates completely 99% of theoretical H2 storage capacity, while that of nanoconfined 2LiBH4?MgH2 is only 94%. Nanoconfined 2LiBH4-MgH2-0.13TiCl4 performs three-step dehydrogenation at 140, 240, and 380ºC. Onset (the first-step) dehydrogenation temperature (140ºC), significantly lower than those of nanoconfined sample of 2LiBH4-MgH2 and 2LiBH4-MgH2-TiCl3 (DT = 140 and 110ºC, respectively) is in agreement with the decomposition of eutectic LiBH4-Mg(BH4)2 and lithium?titanium borohydride. For the second and third steps (240 and 380ºC),decompositions of LiBH4 destabilized by LiCl solvation and MgH2 are accomplished, respectively. In conclusion, dehydrogenation products are B, Mg, LiH, and TiH. Reversibility of nanoconfined 2LiBH4-MgH2-0.13TiCl4 sample is confirmed by the recovery of LiBH4 after rehydrogenation together with the formation of [B12H12] derivatives. The superior kinetics during the 2nd, 3rd, and 4th cycles of nanoconfined2LiBH4-MgH2-0.13TiCl4 to the nanoconfined 2LiBH4-MgH2 can be due to the formations of Ti-MgH2 alloys (Mg0.25Ti0.75H2 and Mg6TiH2) during the 1st rehydrogenation.Fil: Gosalawit Utke, Rapee. Institute of Materials Research; Alemania. Suranaree University of Technology; TailandiaFil: Milanese, Chiara. University of Pavia; ItaliaFil: Javadian, Payam. University of Aarhus; DinamarcaFil: Girella, Alessandro. University of Pavia; ItaliaFil: Laipple, Daniel. Institute of Materials Research; AlemaniaFil: Puszkiel, Julián Atilio. Institute of Materials Research; Alemania. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cattaneo, Alice S.. University of Aarhus; DinamarcaFil: Ferrara, Chiara. University of Aarhus; DinamarcaFil: Wittayakhun, Jatuporn. Suranaree University of Technology; TailandiaFil: Skibsted, Jørgen. University of Aarhus; DinamarcaFil: Jensen, Torben R.. University of Aarhus; DinamarcaFil: Marini, Amedeo. University of Pavia; ItaliaFil: Klassen, Thomas. Institute of Materials Research; AlemaniaFil: Dornheim, Martin. Institute of Materials Research; Alemani
Nanoconfined 2LiBH4MgH2TiCl3 in carbon aerogel scaffold for reversible hydrogen storage
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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
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