3,022 research outputs found
Mechanistic insights into CO2 activation via reverse water - Gas shift on metal surfaces
No full textBy
the means of density functional theory calculations, we find
that CO<sub>2</sub> activation via reverse water–gas shift
(r-WGS) follows different elementary steps on different metals (Pt,
Rh, Ni, Cu, Ag, and Pd). We relate these differences to the interactions
between the adsorbed oxygen and the metals, which strongly affect
the dissociation activation energy. In particular, CO<sub>2</sub> dissociation
is favored on metals that present high affinity toward oxygen. As
the O interaction with the metals weakens, CO<sub>2</sub> hydrogenation
becomes more favored at the expenses of the dissociation. We found
that the binding energy of oxygen scales almost linearly with the
difference between the activation energy of the two competing paths,
and therefore this quantity can be used as a simple descriptor to
discriminate which of the two mechanisms is dominant on different
metals. Such findings allow rationalization of the different catalytic
cycles reported in the literature for the r-WGS reaction on metal
surfaces
Rozpor ako východisko, láska ako smer u Simone Weilovej (Contradiction as base, Love as direction in writings of Simone Weil)
No full textArticle is explaining contradiction and love, Simone Weil‘s essential terms of hermeneutics of human Being. It introduces close relation of these terms with her understanding of God as well as with her overall concept of religion. Author also mentions Simone Weil‘s inspirations with philosophical and spiritual concepts of the East
A first principles study of water oxidation catalyzed by a tetraruthenium-oxo core embedded in polyoxometalate ligands
No full textWe present a computational study addressing the catalytic cycle of a recently-synthesized all-inorganic homogeneous catalyst capable to promote water oxidation with low overpotential and high turnover frequency [Sartorel et al., J. Am. Chem. Soc., 2008, 130, 5006; Geletii et al., Angew. Chem., Int. Ed., 2008, 47, 3896]. This catalyst consists of a tetraruthenium-oxo core [Ru(4)O(4)(OH)(2)center dot(H(2)O)(4)](6+) capped by two polyoxometalate [SiW(10)O(36)](8-) units. The reaction mechanism underpinning its efficiency is currently under debate. We study a reaction cycle involving four consecutive proton-coupled electron transfer (PCET) processes that successively oxidize the four Ru(IV)-H(2)O units of the initial state (S(0)) to the four Ru(V)-OH centers of the activated intermediate (S(4)). The energetics of these electrochemical processes as well as the structural and electronic properties of the reaction intermediates are studied with ab initio Density Functional Theory (DFT) calculations. After characterizing these reaction intermediates in the gas phase, we show that the solvated tetraruthenate core undergoes a solvent-induced structural distortion that brings the predicted molecular geometry to excellent agreement with the experimental X-ray diffraction data. The calculated electronic properties of the catalyst are instead weakly dependent on the presence of the solvent. The frontier orbitals of the initial state as well as the electronic states involved in the PCET steps are shown to be localized on the tetraruthenium-oxo core. The reaction thermodynamics predicted for the intermediate reaction steps is in good agreement with the available cyclic voltammetry measurements up to S(3), but the calculated free energy difference between the initial and the activated state (S(0)/S(4)) turns out to be significantly lower than the thermodynamic limit for water oxidation. Since the oxidizing power of the S(0)/S(4) couple is not sufficient to split water, we suggest that promoting this reaction would require cycling between higher oxidation states
“I beg you to tell me what has become of Djamila”: The Political Mobilization of Simone de Beauvoir’s Readers During the Boupacha Affair
No full textBy Sophia Millman This is a condensed version of a Masters thesis dedicated to the political mobilization of Simone de Beauvoir’s readers. The citations from the letters were translated from French by the author. *** On June 2, 1960, the French government ordered all copies of the daily Algiers edition of Le Monde seized and destroyed to suppress the publication of Simone de Beauvoir’s article “Pour Djamila Boupacha.” Beauvoir, a self-professed “woman of letters”, not “of action[1]”, and one ..
A comparative study of form and theology in the works of Flannery O'Connor and Simone Weil
No full textIn this comparative study of the form and theology of Flannery O'Connor and Simone Weil I interrogate how Weil's philosophical writings and her theology illuminate O'Connor's use of both narrative and non-fictional forms, and her Catholicism. The Introduction analyses how Weil's concept of superposed reading provides a new method of approaching both O'Connor, her writings, and O'Connor
studies, and focuses on how such apparently different women interconnect. Chapter One explores how both Weil and O'Connor attempt to write their theologies on the
souls of their readers yet are each subject to constraints imposed by form. Weil's concept of locating equilibrium between incommensurates is discussed, and her
distinctively philosophical approach to fictions and fictionality is used to investigate O'Connor's notion of prophetic fictions and the writer's role. Chapter Two assesses how both writers revivify Christian paradoxes. Weil's monstrous concept of affiiction, and O'Connor's use of the grotesque genre to jolt secular man into an
awareness of the sacred are scrutinised. Chapter Three studies how both writers consider an encounter between God and man is possible through the action of grace. My Conclusion interrogates how Weil's work can deepen our understanding of O'Connor's writings, and examines how successful O'Connor is at realising a truly
Christian literature. I conclude that despite being a writer of powerful fictions, O'Connor can not be totally successful in her mission as writer-prophet because
ultimately fiction escapes orthodoxy
Microlinices benthovus Simone 2014
No full textbenthovus, Microlinices Simone, 2014 Microlinices benthovus Simone, 2014: 575–578 (figs 6A–J, 7A–H, 11A–C). Gastropoda, Naticidae Paratypes (22 spc): MZSP 105269. Paratypes 1 (15 spc): MZSP 105270. Paratypes 2 (16 spc): MZSP 105271. Paratypes 3 (7 spc): MZSP 105272. Localities: Brazil, Espírito Santo, off Itaúnas, Abrolhos Slope, 18°59' S, 37°50' W, MD55 sta. DC 73, 637 m depth, 27 May 1987; 1) 19°00' S, 37°48' W, MD55 sta. DC72, 950– 1050 m, 27 May 1987; 2) off Regência, 19°40' S, 37°48' W, MD55 sta. CB77, 790– 940 m depth, 27 May 1987; 3) off Itaúnas, Abrolhos Slope, 19°01' S, 37°47' W, MD55 sta. CB79, 1500–1575 m depth, 28 May 1987. Collectors: P. Bouchet, J.H. Leal and B. Métivier. Preservation: Dry. Remarks: Former MNHN, Paris. The catalogue number MZSP 105250 is mentioned twice in Simone’s (2014) paper, among the paratypes of M. ibitingus Simone, 2014 and M. benthovus. This duplicity was a mistake by the author: the latter is an erroneous designation and should be disregarded. The only valid paratype lots for M. benthovus are the ones shown above.Published as part of Cavallari, Daniel C., Dornellas, Ana Paula S. & Simone, Luiz Ricardo L., 2016, Second annotated list of type specimens of molluscs deposited in the Museu de Zoologia da Universidade de São Paulo, Brazil, pp. 1-59 in European Journal of Taxonomy 213 on page 10, DOI: 10.5852/ejt.2016.213, http://zenodo.org/record/384012
Was bringt die Föderalismusreform? Wahrscheinliche Effekte der geänderten Zustimmungspflicht
No full textThe recently enacted reform of German federalism is supposed to make legislation faster, more efficient and better. To what extent are these expectations justified? In order to assess the likely effects of the reform, this study uses a research design that was recently applied by the Research and Reference Services of the German Bundestag (parliament): we estimate the future effects of the reform by analyzing the impact it would have had on the legislation in the 14th and 15th term of the Bundestag if it had already been been in force at that time. In particular we ask: To what extent would the number of laws requiring the consent of the states' chamber, the Bundesrat, have been reduced? Which type of laws would have been affected by this reduction - the more controversial ones, or the less controversial ones? Which policy sectors would have seen the greatest reduction? How much would the reduction have increased the government's capacity to act effectively? Would the legislative process have been accelerated? -- Die verabschiedete Föderalismusreform soll die Gesetzgebung in Deutschland schneller, effizienter und besser machen. Inwiefern sind diese Erwartungen berechtigt? Zur Abschätzung der Reformfolgen auf die Bundesgesetzgebung folgen wir in dem vorliegenden Working Paper einer Vorgehensweise, die der Wissenschaftliche Dienst des Bundestages kürzlich in einer Studie angewandt hat: Die Auswirkungen der Föderalismusreform insbesondere auf die Zustimmungspflicht werden anhand der Gesetzgebung der 14. und 15. Legislaturperiode untersucht. Wir fragen insbesondere: Wie stark hätte sich der Anteil der Zustimmungsgesetze verringert, wenn die neuen Zustimmungsregeln schon in diesen beiden Legislaturperioden gegolten hätten? Wären eher zwischen Regierung strittige oder unstrittige Gesetze von der Zustimmungspflicht befreit worden? Welche Politikbereiche wären betroffen? Wie sehr hätte sich die politische Handlungsfreiheit der Bundesregierung erhöht? Wäre die Gesetzgebung durch die veränderten Zustimmungsregeln beschleunigt worden?
Sensitization of WO3 and SnO2 photoanodes with molecular dyes for water splitting
No full textDyes endowed with strongly oxidizing ground state oxidation potentials are exploited in dye sensitized photoelectrochemical cells for water splitting with the aim of characterizing their interfacial separation dynamics. In the first example [(N,N-Bis(2-(trimethylammonium)-ethylene) perylene 3,4,9,10-tetracarboxylic acid bisimide)-(PF6)2] [1] was observed to spontaneously adsorb onnanocrystalline WO3 surfaces via aggregation/hydrophobic forces. Under visible irradiation (λ > 435 nm), the excited state of the peylene underwent oxidative quenching by electron injection (kinj > 108 s-1) to WO3, leaving a strongly positive hole (Eox ≈ 1.7 V vs SCE), which allows to drive demanding photo-oxidation reactions in photoelectrochemical cells (PECs). The casting of IrO2 nanoparticles (NPs), acting as water oxidation catalysts (WOCs) on the sensitized electrodes, led to a 4-fold enhancement in photoanodic current, consistent with hole transfer from oxidized dye to IrO2 occurring on the microsecond time scale. In a second case study the charge transfer dynamics involving a new Ru(II) polypyridine complex developed to generate strongly oxidizing photoholes for water oxidation, was studied by electrochemical, photo electrochemical and spectroscopic means. Interestingly this species, loaded on TiO2, underwent a change in the injection mechanism in the presence of ascorbic acid, consistent with the reductive quenching of the MLCT excited state and injection from the photo generated reduced state. On the other hand the usual oxidative quenching was observed on SnO2 photo anodes, where the activation of IrO2 by the oxidized state of the sensitizer was observed. Once the interaction with suitable WOCs is optimized, these molecular designs may hold potentialities for the straightforward building of molecular level devices for solar fuel production
Idea ofiary u Simone Weil
No full textAutorka omawia ofiarę, jaką z samej siebie złożyła Simone Weil. Głównym celem autorki artykułu jest wykazanie, iż idea ofiary była najważniejszą myślą w życiu francuskiej filozof. W artykule ukazano myśl o ofierze w życiu i pismach intelektualistki, jak również analogie, które rzucają nowe światło na ofiarę Weil. Jako klucz do interpretacji i zrozumienia ofiary Weil, autorka analizuje myśl Emmanuela Levinasa oraz Józefa Tischnera.The author interprets the sacrifice that Simone Weil filed with itself. The main point of the present article is the assumption that the sacrifice Simone Weil was the most important idea of her life. A thought about the victim is portraying the article in the life and letters of the intellectual, as well as is portraying analogies which are shedding new light on the Weil victim. As the key to interpretation and understanding the her victim, the author is analysing the thought of Emmanuel Levinas and Jozef Tischner.Udostępnienie publikacji Wydawnictwa Uniwersytetu Łódzkiego finansowane w ramach projektu „Doskonałość naukowa kluczem do doskonałości kształcenia”. Projekt realizowany jest ze środków Europejskiego Funduszu Społecznego w ramach Programu Operacyjnego Wiedza Edukacja Rozwój; nr umowy: POWER.03.05.00-00-Z092/17-00
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