841 research outputs found

    Interaction of the ionic liquid [BMP][TFSA] with rutile TiO2(110) and coadsorbed lithium

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    Aiming at a fundamental understanding of the processes at the electrode|ionic liquid interface in Li ion batteries, we investigated the interaction of the ionic liquid n-butyl-n-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide [BMP][TFSA] and of Li with a reduced rutile TiO2(110) (1 × 1) surface as well as the interaction between [BMP][TFSA] and Li on the TiO2(110) surface under ultrahigh vacuum (UHV) conditions by X-ray photoelectron spectroscopy and scanning tunnelling microscopy. Between 80 K and 340 K [BMP][TFSA] adsorbs molecularly on the surface and at higher temperatures decomposition is observed, resulting in products such as Sad, Fad and TiNx. The decomposition pattern is compared to proposals based on theory. Small amounts of Li intercalate even at 80 K into TiO2(110), forming Li+ and Ti3+ species. The stoichiometry in the near surface region corresponds to Li7Ti5O12. For higher coverages in the range of several monolayers part of the Li remains on the surface, forming a Li2O cover layer. At 300 K, Ti3+ species become sufficiently mobile to diffuse into the bulk. Li post-deposition on a [BMP][TFSA] covered TiO2(110) surface at 80 K results in two competing reactions, Li intercalation and reaction with the IL, resulting in the decomposition of the IL. Upon warming up, the Ti3+ formed at low T is consumed by reaction with the IL adlayer and intermediate decomposition products. Post-deposition of [BMP][TFSA] (300 K) on a surface pre-covered with a Li2O/Li7Ti5O12 layer results in the partial reaction of [BMP][TFSA] with the Li+ and Ti3+ species, which gets completed at higher temperatures

    Amadis of Gaul, Books I and II: A Novel of Chivalry of the 14th Century Presumably First Written in Spanish

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    Includes a new Introduction by John E. Keller In the long history of European prose fiction, few works have been more influential and more popular than the romance of chivalry Amadis of Gaul . Although its original author is unknown, it was probably written during the early fourteenth century. The first great bestseller of the age of printing, Amadis of Gaul was translated into dozens of languages and spawned sequels and imitators over the centuries. A handsome, valiant, and undefeatable knight, Amadis is perhaps best known today as Don Quixote’s favorite knight-errant and model. This exquisite English translation restores a masterpiece to print. A most welcome arrival. It\u27s availability opens up the possibility of a wider, general audience, and of teaching Amadis not only to the graduate comparatist, but also to the large undergraduate audience. -- Bulletin of Spanish Studies What made the original and its sequels international bestsellers in the early age of printing is bound to appeal to many modern readers. Amadis combines the sentimental with the chivalric, while adding bountiful measures of pure adventure and fantasy. -- La Coronica Set in and around England after the Roman era, but before the advent of Arthur, it tells the complex interwoven story of the adventures of Amadis, the greatest knight of all time. . . . This 16th century bestseller presents an exciting, past-paced and ultimately very entertaining story that modern readers should have little difficulty in appreciating. -- SF Sitehttps://uknowledge.uky.edu/upk_spanish_literature/1002/thumbnail.jp

    Interaction of ionic liquids with noble metal surfaces: Structure formation and stability of [OMIM][TFSA] and [EMIM][TFSA] on Au(111) and Ag(111)

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    Principles of structure formation and adsorbate–adsorbate interactions in ionic liquid adlayers on metal surfaces were investigated in a comparative STM study on Ag(111) and Au(111) surfaces.</p

    Effect of Exercise-Related Factors on the Perception of Time

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    The concept of time whether considered through the lenses of physics or physiology is a relative measure. Alterations in time perception can have serious implications in sport, fitness and work. Accurate perception of time is an important skill with many time constrained sports (i.e., basketball, North American football, tennis, gymnastics, figure skating, ice hockey, and others), and work environments (i.e., workers who need to synchronize their actions such as police and military). In addition, time distortions may play a role in exercise adherence. Individuals may be disinclined to continue with healthy, exercise activities that seem protracted (time dilation). Two predominant theories (scalar expectancy theory and striatal beat frequency model) emphasize the perception of the number of events in a period and the role of neurotransmitters in activating and coordinating cortical structures, respectively. A number of factors including age, sex, body temperature, state of health and fitness, mental concentration and exercise intensity level have been examined for their effect on time perception. However, with the importance of time perception for work, sport and exercise, there is limited research on this area. Since work, sports, and exercise can involve an integration of many of these aforementioned factors, they are interventions that need further investigations. The multiplicity of variables involved with work, sport, and exercise offer an underdeveloped but fruitful field for future research. Thus, the objective of this review was to examine physiological and psychological factors affecting human perception of time and the mechanisms underlying time perception and distortion with activity

    Rechargeable Calcium–Sulfur Batteries Enabled by an Efficient Borate-Based Electrolyte

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    Rechargeable metal–sulfur batteries show great promise for energy storage applications because of their potentially high energy and low cost. The multivalent‐metal based electrochemical system exhibits the particular advantage of the feasibility of dendrite‐free metal anode. Calcium (Ca) represents a promising anode material owing to the low reductive potential, high capacity, and abundant natural resources. However, calcium–sulfur (Ca–S) battery technology is in an early R&D stage, facing the fundamental challenge to develop a suitable electrolyte enabling reversible electrochemical Ca deposition, and at the same time, sulfur redox reactions in the system. Herein, a study of a room‐temperature Ca–S battery by employing a stable and efficient calcium tetrakis(hexafluoroisopropyloxy) borate Ca[B(hfip)4_{4}]2_{2} electrolyte is presented. The Ca–S batteries exhibit a cell voltage of ≈2.1 V (close to its thermodynamic value) and good reversibility. The mechanistic studies hint at a redox chemistry of sulfur with polysulfide/sulfide species involved in the Ca‐based system

    Potential Energy Surface for H_2 Dissociation over Pd(100)

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    The potential energy surface (PES) of dissociative adsorption of H_2 on Pd(100) is investigated using density functional theory and the full-potential linear augmented plane wave (FP-LAPW) method. Several dissociation pathways are identified which have a vanishing energy barrier. A pronounced dependence of the potential energy on ``cartwheel'' rotations of the molecular axis is found. The calculated PES shows no indication of the presence of a precursor state in front of the surface. Both results indicate that steering effects determine the observed decrease of the sticking coefficient at low energies of the H_2 molecules. We show that the topology of the PES is related to the dependence of the covalent H(s)-Pd(d) interactions on the orientation of the H_2 molecule.Comment: RevTeX, 8 pages, 5 figures in uufiles forma

    Study of St. Paul's Rehabilitation Program

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    Center for Urban and Regional Affairs, University of Minnesota for the City of St. Paul
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