186 resultados para attractions


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We developed a coarse-grained yet microscopic detailed model to study the statistical fluctuations of single-molecule protein conformational dynamics of adenylate kinase. We explored the underlying conformational energy landscape and found that the system has two basins of attractions, open and closed conformations connected by two separate pathways. The kinetics is found to be nonexponential, consistent with single-molecule conformational dynamics experiments. Furthermore, we found that the statistical distribution of the kinetic times for the conformational transition has a long power law tail, reflecting the exponential density of state of the underlying landscape. We also studied the joint distribution of the two pathways and found memory effects.

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Organically modified montmorillonites (OMMTs) by octadecylammonium chloride with two adsorption levels were dispersed in polyamide 12 (PA12) matrices with two molecular weights for different melt mixing times in order to investigate morphology evolutions and factors influencing fabrication of PA12 nanocomposites. Different adsorption levels of the modifier in the OMMTs provide different environments for diffusion of polymer chains and different attractions between MMT layers. Wide-angle X-ray diffraction (WAXD), transmission electron microscope (TEM) and gas permeability were used to characterize morphologies of the nanocomposites. Both OMMTs can be exfoliated in the PA12 matrix with higher molecular weight, but only OMMT with lower adsorption level can be exfoliated in the PA12 matrix with lower molecular weight. It was attributed to the differences in the levels of shear stress and molecular diffusion in the nanocomposites. The exfoliation of OMMT platelets results from a combination of molecular diffusion and shear. After intercalation of PA12 into interlayer of OMMT in the initial period of mixing, further dispersion of OMMTs in PA12 matrices is controlled by a slippage process of MMT layers during fabricating PA12 nanocomposites with exfoliated structure.

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Substantial progress has been made recently in extending the supramolecular assembly of biomimetic structures to vesicle-based sophisticated nanocomposites and mesostructures. We report herein the successful preparation of unilamellar surfactant vesicles coated with a monolayer of ring-shaped {Mo-154} polyoxometalate (POM) nanoclusters, (NH4)(28)[Mo-154 (NO)(14)O(448)Hi(4)(H2O)(70)].approximate to 350H(2)O, by coulomb attractions using preformed didodecyldimethylammonium bromide (DDAB) surfactant vesicles as templates. The resultant vesicle-templated supramolecular assemblies are robust (they do not disintegrate upon dehydration) both at room-temperature ambient and vacuum conditions, as characterized by conventional transmission electron microscopy (TEM) and atomic force microscopy (AFM). The flexibility of the complex soft assemblies was also revealed by AFM measurements. The effect of POM-vesicle coulomb attractions on the dimensions of the templating vesicles was also investigated by using dynamic light scattering (DLS).Although origins of the structure stability of the as-prepared supramolecular assemblies are not clear yet, the nanometer scale cavities and the related properties of macroions of the POM clusters may play an important role in it.

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A new compound, (CH5N2)(3)(PMo12O40CH4N23H2O)-C-.-H-. (1), was synthesized and structurally characterized by elemental analyses, IR spectra, UV spectra, NMR spectra and ESR spectra. This is, to our knowledge, the first example of an imidazole-polyoxometalate species. The compound was recrystallized from N,N-dimethylformamide (DMF), and then black block-like crystals of (C3H5N2)(4)((PMoMo11O40)-Mo-V-O-VI)(.)4C(3)H(7)NO(.) 2H(2)O (2), were obtained. It crystallizes in a triclinic space group P (1) over bar with n=12.423(3) Angstrom, b=12.666(3) Angstrom, c=13.341(3) Angstrom, alpha=70.56(3)degrees, beta=71.16(3)degrees, gamma=64.18(3)degrees, V= 1742.3(6) Angstrom(3), Z=1, R1 = 0.0585, wR2 = 0.1885. An X-ray crystallographic study showed that the crystal structure is constructed by electrostatic attractions and hydrogen bonds between a dodecamolybdophosphoric anion and an imidazole. The imidazole and DMF molecules occupy cavities in a polyoxometalate lattice ordered along a c-axis. The structure of (2) is similar to that of (1) from a comparison of both IR spectra and TGA Curves.

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Gibbs, N., Getting Constitutional Theory into Proportion: A Matter of Interpretation?, Oxford Journal of Legal Studies, 27 (1), 175-191. RAE2008

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Garrod, Brian, Leask, Anna and Fyall, Alan (2007) An assessment of ?international best practice? in visitor attraction management: does Scotland really lag behind? International Journal of Tourism Research, 9 (1), 21-42. RAE2008

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The paper discusses social practices of creating as well as producing authentic objects and space. My deliberations are based on the thesis of the authors of the books The tourist gaze (John Urry), The tourist. A new theory of the leisure class (Dean MacCannell); Contested natures (Phil Macnaghten and John Urry), but also on my own research concerning attitudes towards wolfs in western and eastern Poland. The point of the article is that at the age of the new visual media, postmodernism and posttourism, when it is difficult to recognize whether an object is the original or a copy, man still wants to stand on the firm ground of genuine values. The sociologists mentioned above claim that this is why in the modern world there is a demand for authentic objects and so in an answer to this need such attractions like w i l d n e s s and r u s t i c i t y are produced. In the first part of the article I present an example of a visual product – an English cottage. Secondly, basing on the results of some research concerning attitudes towards wolves, I attempt to show that in Poland there are also some practices the idea of which is to create an authentic space - wild nature. Finally I emphasize that constructed authentic space, scenes, and landscapes are examples of myths – wildness, rusticity – the consequence of nostalgia for lost authentic world.

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Using thermosetting epoxy based conductive adhesive films for the flip chip interconnect possess a great deal of attractions to the electronics manufacturing industries due to the ever increasing demands for miniaturized electronic products. Adhesive manufacturers have taken many attempts over the last decade to produce a number of types of adhesives and the coupled anisotropic conductive-nonconductive adhesive film is one of them. The successful formation of the flip chip interconnection using this particular type of adhesive depends on, among factors, how the physical properties of the adhesive changes during the bonding process. Experimental measurements of the temperature in the adhesive have revealed that the temperature becomes very close to the required maximum bonding temperature within the first 1s of the bonding time. The higher the bonding temperature the faster the ramp up of temperature is. A dynamic mechanical analysis (DMA) has been carried out to investigate the nature of the changes of the physical properties of the coupled anisotropic conductive-nonconductive adhesive film for a range of bonding parameters. Adhesive samples that are pre-cured at 170, 190 and 210°C for 3, 5 and 10s have been analyzed using a DMA instrument. The results have revealed that the glass transition temperature of this type of adhesive increases with the increase in the bonding time for the bonding temperatures that have been used in this work. For the curing time of 3 and 5s, the maximum glass transition temperature increases with the increase in the bonding temperature, but for the curing time of 10s the maximum glass transition temperature has been observed in the sample which is cured at 190°C. Based on these results it has been concluded that the optimal bonding temperature and time for this kind of adhesive are 190°C and 10s, respectively.

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The environmental attractions of air-cycle refrigeration are considerable. Following a thermodynamic design analysis, an air-cycle demonstrator plant was constructed within the restricted physical envelope of an existing Thermo King SL200 trailer refrigeration unit. This unique plant operated satisfactorily, delivering sustainable cooling for refrigerated trailers using a completely natural and safe working fluid. The full load capacity of the air-cycle unit at -20 °C was 7,8 kW, 8% greater than the equivalent vapour-cycle unit, but the fuel consumption of the air-cycle plant was excessively high. However, at part load operation the disparity in fuel consumption dropped from approximately 200% to around 80%. The components used in the air-cycle demonstrator were not optimised and considerable potential exists for efficiency improvements, possibly to the point where the air-cycle system could rival the efficiency of the standard vapour-cycle system at part-load operation, which represents the biggest proportion of operating time for most units.

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The effects of linear scaling of the atomic charges of a reference potential on the structure, dynamics, and energetics of the ionic liquid 1,3-dimethylimidazolium chloride are investigated. Diffusion coefficients that span over four orders of magnitude are observed between the original model and a scaled model in which the ionic charges are +/- 0.5 e. While the three-dimensional structure of the liquid is less affected, the partial radial distribution functions change markedly-with the positive result that for ionic charges of +/- 0.7 e, an excellent agreement is observed with ab initio molecular dynamics data. Cohesive energy densities calculated from these partial-charge models are also in better agreement with those calculated from the ab initio data. We postulate that ionic-liquid models in which the ionic charges are assumed to be +/- 1 e overestimate the intermolecular attractions between ions, which results in overstructuring, slow dynamics, and increased cohesive energy densities. The use of scaled-charge sets may be of benefit in the simulation of these systems-especially when looking at properties beyond liquid structure-thus providing on alternative to computationally expensive polarisable force fields.

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The effect of dye molecular charges on their adsorption from solution was investigated by using different types of activated carbon adsorbents. Two types of model systems were used representing cationic and anionic dyes. Screening investigations using single point tests were used throughout the study. Cationic dyes, of which Methylene Blue is an example, showed a higher adsorption tendency towards activated carbon over anionic dyes represented by an ate-type reactive compound. Of the number of activated carbons tested, only one of the adsorbents showed an exception to this behavior, and a good relation was observed between Methylene Blue capacity and activated carbon performance. The high capacity of cationic dyes in comparison to anionic dyes was also evident in the results obtained by a preliminary kinetic study carried out on the selected systems. Surface net charge of activated carbon and the nature of attractions between the molecules were suggested to be one of the reasons attributed for this behavior.

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In Japan yaen koen or ‘wild monkey parks’ are popular visitor attractions that show free-ranging monkey troops to the paying public. Unlike zoos, which display animals through confinement, monkey parks control the movements of the monkeys through provisioning. The parks project an image of themselves as ‘natural zoos’, claiming to practice a more authentic form of wild animal display than that practiced by the zoo. This article critically evaluates the monkey park’s claim by examining park management of the monkeys. The monkey park’s claim to display ‘wild monkeys’ is shown to be questionable because of the way that provisioning changes monkey behaviour. Against the background of human encroachment onto the forest habitat of the monkey, the long-term effect of provisioning is to sedentarize what were nomadic monkeys and to turn the ‘wild monkey park’ into a megazoo.

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The intention of this article is not to affirm, but rather to question wether it is possible to speak of a loss of the ability to gaze in the context of the nineteenth century and especially in the context of the fin de siècle, in the bosom of the epistemological crisis that beset the Turn of the Century. And very especially, this article tries to question about the impact this crisis had, perhaps, in the birth of cinema. Is in this context that arises the work of Marey and the advent of the cinematograph of the Lumière brothers in the fin de siècle Europe, both of them showing a deep faith in a mechanical apparatus that would allow the redemption of a battered gaze. And it seems to be a dream that continues over time through the tradition of shooting the everyday life.

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The Universal Declaration on Human Rights was pivotal in popularizing the use of 'dignity' or 'human dignity' in human rights discourse. This article argues that the use of 'dignity', beyond a basic minimum core, does not provide a universalistic, principled basis for judicial decision-making in the human rights context, in the sense that there is little common understanding of what dignity requires substantively within or across jurisdictions. The meaning of dignity is therefore context-specific, varying significantly from jurisdiction to jurisdiction and (often) over time within particular jurisdictions. Indeed, instead of providing a basis for principled decision-making, dignity seems open to significant judicial manipulation. increasing rather than decreasing judicial discretion. That is one of its significant attractions to both judges and litigators alike. Dignity provides a convenient language for the adoption of substantive interpretations of human rights guarantees which appear to be intentionally, not just coincidentally. highly contingent on local circumstances. Despite that, however, I argue that the concept of 'human dignity' plays an important role in the development of human rights adjudication, not in providing an agreed content to human rights but in contributing to particular methods of human rights interpretation and adjudication.

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New Irish speakers in Belfast play a crucial, complex part in the revitalization and change of both the city and Irish within Northern Ireland. This paper examines the role of new Irish speakers in transforming Belfast, whose emergence from a post-conflict period involves a reassessment of communal cultural expressions. Markers of ethno-national identity are bitterly contentious locally, and yet increasingly celebrated, in line with international trends, as high status cultural forms and potentially profitable tourist attractions. Irish in Belfast currently occupies an ambiguous position: divisive enough for a sign reading ‘Happy Christmas’ in Irish to be experienced as an insult by some city councillors, yet a secure enough part of the establishment for a neighbourhood to be officially rebranded as the Gaeltacht Quarter.
When, how and where new Irish speakers use the language in Belfast has implications for the relationship of Irishness to the Northern Irish state and for the place of Belfast within regional frameworks across the UK, Ireland and Europe. Adult learners and young people exiting Irish medium education have an impact on life in Belfast beyond its small population of Irish speakers. Urbanisation fuelled by new speakers, which shifts the balance of Irish language resources and speakers away from traditional rural Gaeltacht areas and towards cities, also has implications for the language itself. Recent increase in new Irish speakers in Belfast is due to expansion in the Irish-medium sector as well as to adult learners, whose decisions contribute to the school expansion.
Urbanisation, multilingualism and intergenerational shift combine in Belfast to produce new linguistic norms. Moreover, in a minority language community where hierarchies of ‘authenticity’ are weighted towards the rural and the native speaker, where the rural and the native have traditionally been conflated, and where indigeneity is a central concept to contested nationalisms, the emergence of a self-confident, youthful Irish speaking community in Northern Ireland’s biggest city involves a recalibration of the qualities signifying ‘gaelicness’. As students, professionals, hobbyists and activists, new Irish speakers in Belfast occupy a vital position at the crux of changing ideas about place, language and identity.