36 resultados para force field
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This work is divided into two distinct parts. The first part consists of the study of the metal organic framework UiO-66Zr, where the aim was to determine the force field that best describes the adsorption equilibrium properties of two different gases, methane and carbon dioxide. The other part of the work focuses on the study of the single wall carbon nanotube topology for ethane adsorption; the aim was to simplify as much as possible the solid-fluid force field model to increase the computational efficiency of the Monte Carlo simulations. The choice of both adsorbents relies on their potential use in adsorption processes, such as the capture and storage of carbon dioxide, natural gas storage, separation of components of biogas, and olefin/paraffin separations. The adsorption studies on the two porous materials were performed by molecular simulation using the grand canonical Monte Carlo (μ,V,T) method, over the temperature range of 298-343 K and pressure range 0.06-70 bar. The calibration curves of pressure and density as a function of chemical potential and temperature for the three adsorbates under study, were obtained Monte Carlo simulation in the canonical ensemble (N,V,T); polynomial fit and interpolation of the obtained data allowed to determine the pressure and gas density at any chemical potential. The adsorption equilibria of methane and carbon dioxide in UiO-66Zr were simulated and compared with the experimental data obtained by Jasmina H. Cavka et al. The results show that the best force field for both gases is a chargeless united-atom force field based on the TraPPE model. Using this validated force field it was possible to estimate the isosteric heats of adsorption and the Henry constants. In the Grand-Canonical Monte Carlo simulations of carbon nanotubes, we conclude that the fastest type of run is obtained with a force field that approximates the nanotube as a smooth cylinder; this approximation gives execution times that are 1.6 times faster than the typical atomistic runs.
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Dissertation to obtain a Master degree in Biotechnology
Cultural innovation and transmission of tool use in wild chimpanzees:evidence from field experiments
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Animal Cognition, V.6, pp. 213-223
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IEEE Electron Device Letters, VOL. 29, NO. 9,
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Paper presented at the 9th European Conference on Knowledge Management, Southampton Solent University, Southampton, UK, 4-5 Sep. 2008. URL: http://academic-conferences.org/eckm/eckm2008/eckm08-home.htm
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1st European IAHR Congress,6-4 May, Edinburg, Scotland
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The objective of the article is to evaluate the impact of the friction force mouse-pad in the contraction level of the forearm muscles M. extensor carpi ulnaris, M. extensor digitorum and M. extensor carpi radialis longus. A standard protocol of mouse movements was performed involving horizontal, vertical and diagonal mouse displacements drag-and-drop type. The operators were instructed to execute the protocol with their normal working speed. The movements protocol were performed by each subject (n=17) with three selected pairs mouse-pad, classified as low, medium and high friction force pairs. The mean time to execute the protocol with each mouse was ~138s. Mean values of ~13%MVE and ~17%MVE were found in the M. extensor carpi ulnaris and in the M. extensor digitorum respectively when performing the movements’ protocol. A 8.1% increase in %MVE was observed in the M. extensor digitorum and a 9.4% increase in %MVE was observed in the M. extensor carpi ulnaris when the high friction force pair was operated, relatively to the low friction force pair (p<0.05). The main preliminary conclusions of this study is that operating a high friction force mouse-pad may increase the risk to symptoms or disorders in the wrist due to an increase in the forearm muscles contraction levels, particularly during work with drawing application
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Paper presented at the 5th European Conference Economics and Management of Energy in Industry, Vilamoura, Algarve. Apr. 14-17, 2009, 11p. URL: http:// www.cenertec.pt/ecemei/
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Dissertação apresentada como requisito parcial para obtenção do grau de Mestre em Gestão de Informação
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Relatório de Estágio apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Ciência Política e Relações Internacionais, na variante de Estudos Europeus
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Dissertação para obtenção do Grau de Doutor em Nanotecnologias e Nanociências
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Finance from the NOVA – School of Business and Economics
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A Work Project, presented as part of the requirements for the Award of a Masters Degree in Management from the NOVA – School of Business and Economics
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The limitations of access to finance in Africa, together with the recent boom in cell phone use in that continent, created high expectations regarding the introduction of mobile money in many African countries. The success story of M-PESA in Kenya raised the bar further. We designed and conducted a field experiment to assess the impact of randomized mobile money dissemination in rural Mozambique. For this purpose we benefit from the fact that mobile money was only recently launched in the country, allowing for the identification of a pure control group. This paper reports on the first results of this ongoing project after the first wave of dissemination efforts in rural locations, which included the recruitment and training of mobile money agents, community meetings and theaters, as well as individual rural campaigning. Administrative and behavioral data both show clear adherence to the services in the treatment group. Financial literacy and trust outcomes are also positively affected by the treatment. We present behavioral evidence that the marginal willingness to remit was increased by the availability of mobile money. Finally, we observe a tendency for mobile money to substitute traditional alternatives for both savings and remittances.