973 resultados para mobilidade de Zn


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DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

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DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

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This paper compares the crack growth resistance of an experimental spray-formed extrusion with that of a commercial aluminium alloy, the two alloys having similar compositions but markedly different grain structures. Tensile and fracture behaviour is similar in both materials and is influenced by inclusion content. The two materials differ in their crack growth resistance, which is shown to be dependent upon grain size and shape. Environmentally-induced crack growth is favoured by aligned grain boundaries and small grain size.

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Intercalation of an in situ prepared [Rh(OH)6]3- complex into an anion exchangeable Ni-Zn layered hydroxy double salt (Rh/NiZn) was demonstrated. The resulting Rh/NiZn effectively catalyzed the 1,4-addition of diverse enones and phenylboronic acids to their corresponding β-substituted carbonyl compounds. In the case of 2-cyclohexen-1-one and phenylboronic acid, a turnover frequency (TOF) of 920 h-1 based on Rh was achieved. The [Rh(OH)6]3- complex maintained its original monomeric trivalent state within the NiZn interlayer following catalysis, attributable to a strong electrostatic interaction between the NiZn host and anionic Rh(III) complex.

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The use of calcium hydroxide for scavenging zincate species is demonstrated to be a highly effective approach for increasing the electrolyte capacity and improving the performance of the zinc-air fuel cell system. A fundamental approach is established in this study to quantify the formation of calcium zincate as the product of scavenging and the amount of water compensation necessary for optimal performance. The good agreement between predicted and experimental results proves the validity of the proposed theoretical approach. By applying the results of theoretical predictions, both the electrolyte capacity and the cell longevity have been increased by more than 40%. It is also found that, using Ca(OH)2 to scavenge zincate species in concentrated KOH solutions, affects mostly the removal of zincate, rather than ZnO, from the electrolyte, whereas the presence of excess, free, mobile H2O plays a key role in dissolving ZnO and forming zincate. The results obtained in this study demonstrate that the proposed approach can widely and effectively be applied to all zinc-air cell systems during their discharge cycle.

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Chemical analyses of manganese nodules from the Central Pacific Basin show that their chemical composition varies regionally, although that of the associated sediments is markedly uniform throughout the basin. Mn content varies from 16 to 32% in average. Its higher value is generally found in nodules from siliceous clay and a few from deep-sea clay. Fe content tends to enrich in nodules from deep-sea clay area. Most manganese nodules, except those from deep-sea clay, are remarkably depleted in Fe compared with ones from the other Pacific regions. Mostly, Cu and Ni contents exceed 1% in nodules from siliceous clay, and decrease towards the northwest of the basin where deep-sea clay is distributed. The inter-element relationship between manganese nodules and associated sediments suggests that the mechanism of incorporation of major and minor elements in nodules is apparently different from that of the associated sediments. This finding seems to provide a new interpretation on the problem why manganese nodules having low accumulation rate are not buried by the associated sediments with greater sedimentation rate and then occur on sediment-seawater interface.

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The public political investments of urban mobility financed by PAC of Cup 2014 have developed discussions and questions by the civil society in Brazil expecting positive results to the urban infrastructure referring to the possible human rights violation and, specially, rights of habitation related to the removing/expropriation noticed. Natal, capital of Rio Grande do Norte, is into this context, due to the urban mobility project linking North Zone of the city to the Arena das Dunas stadium, financed by the PAC of Cup 2014, named West Structural Corridor, that crosses a field of social interest and proposes almost 400 expropriations. This research analyzes how strategies and mechanisms of integration were presented between the mobility project of West Structural Corridor and the Social Interest Habitation affected by this project. We have as hypothesis those projects financed by PAC of Cup 2014/Urban Mobility to Natal/RN present many problems related to the integration of social interest to the housing project, however the National Politics of Urban Development has planned this integration. As a result we detach 3 strategies in the elaboration process about the integration of those politics: (i) integration between municipal secretaries involved in this project; (ii) urban integration of the city; and (iii) integration of public rules or public politics integrated. For each strategy were presented the main mechanisms used to establish the integration of the project. Those mechanisms, however, in this process of establishment/implementation of the empirical research, presented many contradictions and conflicts that compose problems to the integration between the mobility project and the housing area affected.

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The different characteristics and needs of mobile device users, the situations in which these devices are operated and the limitations and characteristics of these devices are all factors which influence usability and ergonomics; two elements highly required for achieving successful interaction between users and devices. This research aims to identify characteristics of interface design for apps in mobile device applications, focussing on design, visual publishing and content editing, and the actual process of creation of these interfaces, with a view to guarantee quality interaction through touch technology, in observance of service limitations, the opportunities offered by the devices and the application requirements. The study will examine the interface of the mobile device application titled “Brasil 247” which provides news broadcasts using the concept of usability and ergonomics mainly in the field of adaptation, searching and browsing informative articles, as well as clarifying the processes and techniques necessary to carry out interaction tests which seek to evaluate the usability of interface.

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The spread of wireless networks and growing proliferation of mobile devices require the development of mobility control mechanisms to support the different demands of traffic in different network conditions. A major obstacle to developing this kind of technology is the complexity involved in handling all the information about the large number of Moving Objects (MO), as well as the entire signaling overhead required to manage these procedures in the network. Despite several initiatives have been proposed by the scientific community to address this issue they have not proved to be effective since they depend on the particular request of the MO that is responsible for triggering the mobility process. Moreover, they are often only guided by wireless medium statistics, such as Received Signal Strength Indicator (RSSI) of the candidate Point of Attachment (PoA). Thus, this work seeks to develop, evaluate and validate a sophisticated communication infrastructure for Wireless Networking for Moving Objects (WiNeMO) systems by making use of the flexibility provided by the Software-Defined Networking (SDN) paradigm, where network functions are easily and efficiently deployed by integrating OpenFlow and IEEE 802.21 standards. For purposes of benchmarking, the analysis was conducted in the control and data planes aspects, which demonstrate that the proposal significantly outperforms typical IPbased SDN and QoS-enabled capabilities, by allowing the network to handle the multimedia traffic with optimal Quality of Service (QoS) transport and acceptable Quality of Experience (QoE) over time.

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A capacidade de mover-se com independência e segurança é fundamental para a execução das atividades de vida diária e manutenção da qualidade de vida do indivíduo. Diversos fatores, dentre eles o envelhecimento podem contribuir para seu declínio. Estudos têm demonstrado associação entre experiências de violência doméstica (VD) e diversos problemas de saúde física e mental. Até o momento, não há estudos que tenham avaliado a associação entre experiências de VD no curso de vida e limitações de mobilidade na senescência. OBJETIVOS: estimar a prevalência da VD (física e psicológica) em idosos, e avaliar o impacto da VD no curso de vida na limitação de mobilidade. MATERIAIS E MÉTODO: Estudo observacional analítico a partir da primeira coleta de dados do estudo longitudinal International Mobility in Aging Study (IMIAS). Idosos (n = 1995) de ambos os sexos entre 65 e 74 anos de cinco localidades distintas (Kingston e Saint-Hyacinthe, Canadá; Tirana, Albânia; Maniazales, Colômbia; e Natal, Brasil) participaram do estudo. Dados sobre variáveis sociodemográficas, econômicas, condições de saúde e experiências de VD (física e psicológica) durante o curso de vida foram coletados. A limitação de mobilidade na senescência foi avaliada pelo Short Physical Performance Battery (SPPB) e pela dificuldade de andar 400 metros e/ou subir um lance de escadas. As prevalências foram avaliadas mediante frequências absolutas e relativas das exposições à VD, limitação de mobilidade e co-variáveis. Diferenças de gênero, bem como entre cidades foram analisadas utilizando o teste de qui-quadrado. Associação entre exposição à VD e limitação de mobilidade foi avaliada utilizando a regressão logística binária multivariada, ajustando pelas co-variáveis. Análise de mediação foram utilizadas, para avaliar possíveis caminhos entre a exposição à VD no curso de vida e a limitação de mobilidade. RESULTADOS: A violência física foi rara, com valores entre 0,63 e 0,85%. Relatos de violência psicológica variaram entre 3,2% e 23,5% (homens) e de 9% para 26% (mulheres). Mulheres experimentaram mais violência do que os homens em Saint-Hyacinthe (homens: 3,2% vs mulheres: 14%, p <0,001), Tirana (homens: 4,3% vs mulheres: 10,3%, p = 0,017), em Manizales (homens: 8,3 % vs mulheres: 18,3%, p = 0,004) e Natal (homens: 11,1% vs mulheres: 26%, p = 0,002). Em geral, o baixo suporte social pelo parceiro foi associado com a VD. Estar trabalhando foi associado a vitimização entre os homens, enquanto o oposto foi verdade para as mulheres. Arranjos de vida Multi-familiares e baixo suporte pelos parceiros, filhos e família foram associados com a VD. Baixo suporte social foi da maior importância para as mulheres do que os homens. A VD física foi associada tanto com o SPPB < 8 (OR 1,623 95%IC 1,161-2,269) como com a dificuldade para andar 400 metros e/ou subir um lance de escadas (OR 1,394 95%IC 1,063-1,829). A limitação de mobilidade decorrente da violência física no curso de vida pelo parceiro íntimo foi mediada pelas condições crônicas (efeito 25,56% 95%IC 0,036-0,277) e depressão (efeito 33,05% 95%IC 0,087-0,333). No caso da violência física por outros familiares, a limitação de mobilidade foi mediada pelas condições crônicas (efeito 20,85% 95%IC 0,022-0,202), não adesão à prática de atividades físicas (efeito 34,14% 95%IC 0,076-0,351) e depressão (efeito 44,40% 95%IC 0,144-0,315). CONCLUSÕES: A violência doméstica no curso de vida é uma realidade, que pode acarretar consequências que favorecem a limitação de mobilidade em idosos. São necessárias políticas públicas que combatam efetivamente a violência doméstica, garantindo um envelhecimento mais digno e independente funcionalmente.

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The zinc concentration of siliceous sponge spicules was determined from spicules recovered from four sediment cores spanning the last 160 kyr, from the Campbell Plateau region southeast of New Zealand. Zinc/Si results showed little difference between Holocene and glacial aged spicules. An increase in Zn/Si was observed for core Y14, where Zn/Si peaked at about 0.6 ?mol/mol during marine isotope stages 5a-5b. To better understand the role carbon export has on sponge Zn/Si, we explored the strong relationship observed between surficial sediment particulate organic carbon (POC) and the Zn/Si of sponge silica and related this to sediment trap POC flux estimates. Conversion of the Zn/Si records to benthic POC fluxes suggests that there has been little change in the amount of POC reaching Campbell Plateau sediments over the past 30 kyr. These results suggest that surface productivity over the Campbell Plateau has remained relatively low over the past 160 kyr and suggests that glacial productivity was not significantly higher than the present day. Finally, this work reveals that living marine sponges appear to act as the biological equivalents of moored sediment traps, recording the flux of POC to the seafloor by archiving zinc associated with sinking POC in the growing silica skeleton.

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The objective of this study was to verify the association between some mobility items of the International Classification Functionality (ICF), with the evaluations Gross Motor Function Measure (GMFM-88), 1-minute walk test (1MWT) and if the motor impairment influences the quality of life in children with Cerebral Palsy (PC), by using the Paediatric Quality of Life Inventory (PedsQL 4.0 versions for children and parents). The study included 22 children with cerebral palsy spastic, classified in levels I, II, and III on the Gross Motor Function Classification System (GMFCS), with age group of 9.9 years old. Among those who have participated, seven of them were level I, eight of them were level II and seven of them were level III. All of the children and teenagers were rated by using check list ICF (mobility item), GMFM-88, 1-minute walk test and PedsQL 4.0 questionnaires for children and parents. It was observed a strong correlation between GMFM-88 with check list ICF (mobility item), but moderate correlation between GMFM-88 and 1-minute walk test (1MWT). It was also moderate the correlation between the walking test and the check list ICF (mobility item). The correlation between PedsQl 4.0 questionnaires for children and parents was weak, as well as the correlation of both with GMFM, ICF (mobility item) and the walking test. The lack of interrelation between physical function tests and quality of life, indicates that, regardless of the severity of the motor impairment and the difficulty with mobility, children and teenagers suffering of PC spastic, functional level I, II and III GMFCS and their parents have a varied opinion regarding the perception of well being and life satisfaction.

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Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.