51 resultados para Stabilization plan
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
This article examines recent developments in the Cyprus negotiations and suggests a number of changes to the proposed electoral system. Specifically, cross-voting and other electoral methods that encourage coalition-building across ethnic communities might add significantly to the functionality of the Annan Plan. Combined with other innovative mechanisms already in the plan, cross-voting could force political parties to seriously take into account the interests and concerns of the two Cypriot communities, an element that is currently missing from both the Turkish Cypriot (TC) and Greek Cypriot (GC) political systems. Special conditions on the island, as well as the way most political parties operated in the critical pre-April 2004 referendum period, suggest the need for this amendment. Although this study respects the consociational logic of the Annan Plan, it supplements consociationalism with elements that foster integration and inter-dependence between the two communities and their voters. The article also reviews the postreferendum developments in Cyprus which might have worrisome future implications, not only for its two communities, but also for EU enlargement in general. Cyprus both holds one of the keys to Turkey's entrance into the EU and is a litmus test for the Euro-Atlantic nexus and its capacity to pacify and integrate ethnically divided societies in Europe and elsewhere.
Resumo:
The microscopic mechanism leading to stabilization of cubic and tetragonal forms of zirconia (ZrO2) is analyzed by means of a self-consistent tight-binding model. Using this model, energies and structures of zirconia containing different vacancy concentrations are calculated, equivalent in concentration to the charge compensating vacancies associated with dissolved yttria (Y2O3) in the tetragonal and cubic phase fields (3.2 and 14.4% mol, respectively). The model is shown to predict the large relaxations around an oxygen vacancy, and the clustering of vacancies along the 111 directions, in good agreement with experiments and first principles calculations. The vacancies alone are shown to explain the stabilization of cubic zirconia, and the mechanism is analyzed. (C) 2002 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.
Resumo:
The electron energy-loss near-edge structure (ELNES) at the O K edge has been studied in yttria-stabilized zirconia (YSZ). The electronic structure of YSZ for compositions between 3 and 15 mol % Y2O3 has been computed using a pseudopotential-based technique to calculate the local relaxations near the O vacancies. The results showed phase transition from the tetragonal to cubic YSZ at 10 mol % of Y2O3, reproducing experimental observations. Using the relaxed defect geometry, calculation of the ELNES was carried out using the full-potential linear muffin-tin orbital method. The results show very good agreement with the experimental O K-edge signal, demonstrating the power of using ELNES to probe the stabilization mechanism in doped metal oxides.
Thickness-induced stabilization of ferroelectricity in SrRuO3/Ba0.5Sr0.5TiO3/Au thin film capacitors
Resumo:
Pulsed-laser deposition has been used to fabricate Au/Ba0.5Sr0.5TiO3/SrRuO3/MgO thin film capacitor structures. Crystallographic and microstructural investigations indicated that the Ba0.5Sr0.5TiO3 (BST) had grown epitaxially onto the SrRuO3 lower electrode, inducing in-plane compressive and out- of-plane tensile strain in the BST. The magnitude of strain developed increased systematically as film thickness decreased. At room temperature this composition of BST is paraelectric in bulk. However, polarization measurements suggested that strain had stabilized the ferroelectric state, and that the decrease in film thickness caused an increase in remanent polarization. An increase in the paraelectric-ferroelectric transition temperature upon a decrease in thickness was confirmed by dielectric measurements. Polarization loops were fitted to Landau-Ginzburg-Devonshire (LGD) polynomial expansion, from which a second order paraelectric-ferroelectric transition in the films was suggested at a thickness of similar to500 nm. Further, the LGD analysis showed that the observed changes in room temperature polarization were entirely consistent with strain coupling in the system. (C) 2002 American Institute of Physics.
Resumo:
The reversibility of zinc anode in alkaline medium was enhanced by electrostatic deposition of a conducting polymer (polypyrrole). Electropolymerization of pyrrole onto zinc in aqueous medium using an organic acid as dopant is feasible and preferred as zinc is less corrosive in this medium. The structure of the polymer film was analyzed by FT-IR spectroscopy and scanning electron microscopy. The effect of the polypyrrole deposit on the zinc electrode was studied by cyclic voltammetry and charge–discharge cycling.
Resumo:
Sulfoxidation reactions of 4,6-dimethyl-2-methylthiopyrimidine have been performed using titanosilicate catalysts in ionic liquids, dioxane and ethanol. The ionic liquid reactions showed superior reactivity compared with molecular solvents. Moreover, on examination of the recycling of the catalyst, a significant increase in the stability of catalyst was found both in terms of recycling activity and leaching of the titanium from the catalyst. The mechanism by which the ionic liquid reduces the solubilisation of the catalysts is explored.
Resumo:
In Case T-130/06 Drax Power and others v European Commission, the Court of First Instance held that an application by Drax Power and others for annulment of Commission Decision (C(2006)426 final of 22 February 2006 concerning a proposed amendment to the National Allocation Plan notified by the UK in accordance with the EU Emissions Trading Directive was inadmissable. The Court ruled that the applicants could not be considered to be 'directly concerned' by the contested decision within the meaning of the fourth paragraph of Article 230 of the European Treaty, on legal standing: 'Any natural or legal person may, under the same conditions, institute proceedings against a decision addressed to that person or against a decision, which, although in the form of a regulation or a decision addressed to another persion, is of direct and individual concern to the former...'
Resumo:
The tumor suppressor p53 is commonly inhibited under conditions in which the phosphatidylinositide 3'-OH kinase/protein kinase B (PKB) Akt pathway is activated. Intracellular levels of p53 are controlled by the E3 ubiquitin ligase Mdm2. Here we show that PKB inhibits Mdm2 self-ubiquitination via phosphorylation of Mdm2 on Ser(166) and Ser(188). Stimulation of human embryonic kidney 293 cells with insulin-like growth factor-1 increased Mdm2 phosphorylation on Ser(166) and Ser(188) in a phosphatidylinositide 3'-OH kinase-dependent manner, and the treatment of both human embryonic kidney 293 and COS-1 cells with phosphatidylinositide 3'-OH kinase inhibitor LY-294002 led to proteasome-mediated Mdm2 degradation. Introduction of a constitutively active form of PKB together with Mdm2 into cells induced phosphorylation of Mdm2 at Ser(166) and Ser(188) and stabilized Mdm2 protein. Moreover, mouse embryonic fibroblasts lacking PKBalpha displayed reduced Mdm2 protein levels with a concomitant increase of p53 and p21(Cip1), resulting in strongly elevated apoptosis after UV irradiation. In addition, activation of PKB correlated with Mdm2 phosphorylation and stability in a variety of human tumor cells. These findings suggest that PKB plays a critical role in controlling of the Mdm2.p53 signaling pathway by regulating Mdm2 stability.