970 resultados para Armed Services Vocational Aptitude Battery.
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A novel solvothermal method has been used for the synthesis of porous ellipsoidal GeO2 particles with oleic acid and oleylamine as solvent and co-surfactant, respectively and its performance has been studied as an anode material for Li ion battery applications. The presence of highly hydrophobic oleic acid and oleylamine on the surface of the as synthesized sample imparts a detrimental effect on its performance. Although removal of the capping agents with glacial acetic acid improves the performance to some extent, a drastic enhancement in both the specific capacity and cycling stability is observed when the nanoparticles are wrapped with rGO/PANI composites at low temperature. (C) 2015 Elsevier B.V. All rights reserved.
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Rechargeable batteries have been the torchbearer electrochemical energy storage devices empowering small-scale electronic gadgets to large-scale grid storage. Complementing the lithium-ion technology, sodium-ion batteries have emerged as viable economic alternatives in applications unrestricted by volume/weight. What is the best performance limit for new-age Na-ion batteries? This mission has unravelled suites of oxides and polyanionic positive insertion (cathode) compounds in the quest to realize high energy density. Economically and ecologically, iron-based cathodes are ideal for mass-scale dissemination of sodium batteries. This Perspective captures the progress of Fe-containing earth-abundant sodium battery cathodes with two best examples: (i) an oxide system delivering the highest capacity (similar to 200 mA h/g) and (ii) a polyanionic system showing the highest redox potential (3.8 V). Both develop very high energy density with commercial promise for large-scale applications. Here, the structural and electrochemical properties of these two cathodes are compared and contrasted to describe two alternate strategies to achieve the same goal, i.e., improved energy density in Fe-based sodium battery cathodes.
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Sodium-ion-based batteries have evolved as excellent alternatives to their lithium-ion-based counterparts due to the abundance, uniform geographical distribution and low price of Na resources. In the pursuit of sodium chemistry, recently the alluaudite framework Na2M2(SO4)(3) has been unveiled as a high-voltage sodium insertion system. In this context, the framework of density functional theory has been applied to systematically investigate the crystal structure evolution, density of states and charge transfer with sodium ions insertion, and the corresponding average redox potential, for Na2M2(SO4)(3) (M = Fe, Mn, Co and Ni). It is shown that full removal of sodium atoms from the Fe-based device is not a favorable process due to the 8% volume shrinkage. The imaginary frequencies obtained in the phonon dispersion also reflect this instability and the possible phase transition. This high volume change has not been observed in the cases of the Co- and Ni-based compounds. This is because the redox reaction assumes a different mechanism for each of the compounds investigated. For the polyanion with Fe, the removal of sodium ions induces a charge reorganization at the Fe centers. For the Mn case, the redox process induces a charge reorganization of the Mn centers with a small participation of the oxygen atoms. The Co and Ni compounds present a distinct trend with the redox reaction occurring with a strong participation of the oxygen sublattice, resulting in a very small volume change upon desodiation. Moreover, the average deintercalation potential for each of the compounds has been computed. The implications of our findings have been discussed both from the scientific perspective and in terms of technological aspects.
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A number of European countries, among which the UK and Spain, have opened up their Directory Enquiry Services (DQs, or 118AB) market to competition. We analyse the Spanish case, where both local and foreign firms challenged the incumbent as of April 2003. We argue that the incumbent had the ability to abuse its dominant position, and that it was a perfectly rational strategy. In short,the incumbent raised its rivals' costs directly by providing an inferior quality version of the (essential) input, namely the incumbent's subscribers' database. We illustrate how it is possible to quantify the effect of abuse in situation were the entrant has no previous history in the market. To do this, we use the UK experience to construct the relevant counterfactual, that is the "but for abuse" scenario. After controlling for relative prices and advertising intensity, we find that one of the foreign entrants achieved a Spanish market share of only half of what it would have been in the absence of abuse.
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The European Commission Report on Competition in Professional Services found that recommended prices by professional bodies have a significant negative effect on competition since they may facilitate the coordination of prices between service providers and/or mislead consumers about reasonable price levels. Professional associations argue, first, that a fee schedule may help their members to properly calculate the cost of services avoiding excessive charges and reducing consumers’ searching costs and, second, that recommended prices are very useful for cost appraisal if a litigant is condemned to pay the legal expenses of the opposing party. Thus, recommended fee schedules could be justified to some extent if they represented the cost of providing the services. We test this hypothesis using cross‐section data on a subset of recommended prices by 52 Spanish bar associations and cost data on their territorial jurisdictions. Our empirical results indicate that prices recommended by bar associations are unrelated to the cost of legal services and therefore we conclude that recommended prices have merely an anticompetitive effect.
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Work-based learning provider, KEITS has improved efficiencies and institutional effectiveness with the introduction of Blackberry mobile devices to all their assessors. They have saved time and money on paper and travel, diversified evidence capture and improved their overall engagement with learners.
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Broadland Council Training Services have reined in their reliance on traditional learning methods by introducing Xerte/Maxos to their equine-based students. Learners who were once deluged by stacks of paper and unable to utilise an internet connection in a horse yard are now able to access interactive learning exercises using Maxos: Xerte on a memory stick. Students are now more engaged and focused on their studies, teaching methods are much more diverse, and success rates have improved.
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Providing you with peace of mind and due diligence on around 40 pages of contractual terms and conditions on an ongoing basis for Google Apps for Education. JL
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Giving you peace of mind with amendments and due diligence on around 100 pages of contractual documents for Microsoft Office 365.JL