SEM-EDX of morphology of electroless nickel coatings with tin and tungsten

Electroless plating of binary Ni-P, ternary Ni-Sn-P and Ni-W-P, and quaternary Ni-W-Sn-P alloy coatings was carried out in alkalicitrate baths. After the plating, several kinds of test were carried out to determine the improvement in the characteristics and properties due to the additional elements as well as to study the change in behaviour when heat treatment was applied to these coatings. The coatings were subjected to X-ray diffraction analysis where it was found that all the coatings were amorphous. Interesting surface morphology features were examined using scanning electron microscopy. Addition of a third element improved the hardness.

UV dosimeter based on dichloroindophenol and tin(IV) oxide

A UVB specific dosimeter is described comprising: a redox dye (2,6-dichloroindophenol, DCIP), a semiconductor ( tin(IV) oxide, SnO2) and a sacrificial electron donor ( glycerol) dispersed in a polymer ( hydroxy ethyl cellulose, HEC) film. The dosimeter is blue in the absence of UVB light but rapidly loses colour on exposure to UVB light. The spectral characteristics of a typical UVB dosimeter film and the mechanism by which the colour change occurs are detailed. DCIP UVB dosimeter films exhibit a response that is related to the irradiance level and duration of UVB exposure, the level of SnO2 present and to a lesser extent the level of glycerol present. The response of the dosimeter appears to be independent of dye concentration and film thickness. Furthermore, DCIP UVB dosimeter films respond to solar simulated light, exhibiting a colour loss that can be simply related to the Minimal Erythemal Dose (MED) exposure for skin type II. As a consequence, such indicators have potential for measuring solar radiation exposure and providing an early warning of erythema for most Caucasian skin (i.e. skin type II).

“They might as well be walking around the inside of a biscuit tin”: Barriers to Employment and Reintegration for ‘Politically Motivated’ Former Prisoners in Northern Ireland

The prisoner provisions under the Northern Ireland Peace Agreement clearly emphasised the importance of the reintegration and civic inclusion of ‘politically motivated’ former prisoners; however, numerous barriers to full reintegration remain. Even though these prisoners were released as part of a peace process, based on principles of conflict transformation and reconciliation, there were still The prisoner provisions under the Northern Ireland Peace Agreement emphasised the importance of the reintegration and civic inclusion of ‘politically motivated’ former prisoners; however, numerous barriers to full reintegration remain. Notwithstanding the fact that these prisoners were released as part of a peace process, based on principles of conflict transformation and reconciliation, there were still numerous conditions placed upon them as part of their release process and they continued to hold a ‘criminal’ record upon release. As with ‘ordinary’ ex-prisoners, these ‘politically motivated’ former prisoners have subsequently faced numerous obstacles in their attempts to reintegrate back into society, particularly in the area of employment. Recognising that they needed to deal with the consequences of imprisonment, ‘politically motivated’ former prisoners formed numerous self-help organisations to assist in the reintegration process and have mobilised to lobby for protection against the discrimination and unequal treatment experienced by ex-prisoners seeking employment. This article explores the remaining barriers to employment for ‘politically motivated’ former prisoners and the consequences of these barriers. The article moves to assess how prisoner groups have subsequently used a ‘rights based’ discourse to engage local government in their struggle to overcome existing obstacles before finally concluding that any piecemeal attempt to remove barriers to full reintegration will only impede the longer term conflict transformation process in Northern Ireland.

Delamination and wear in drilling of carbon-fiber reinforced plastic composites using multilayer TiAlN/TiN PVD-coated tungsten carbide tools

This study aims to investigate drilling process in carbon-fiber reinforced plastic (CFRP) composites with multilayer TiAlN/TiN PVD-coated tungsten carbide drill. The effect of process parameters have been investigated in drilling of Hexcel M21-T700GC. Thrust force and torque were measured online throughout the drilling experiments. Delamination were observed using optical microscope and analyzed via a developed algorithm based on digital image processing technique. Surface roughness of each hole was measured using a surface profilometer. In addition, the progression of tool wear in various surfaces of drill was observed using tool microscope and measured using image software. Our results indicate that the thrust force and torque increased with the increasing cutting speed and feed rate. Delamination and average surface roughness that rose with the increase in feed rate, however, decreased with the increasing cutting speed. The average surface roughness tended to increase with the increase in feed rate and decrease with the increasing cutting speed in drilling of carbon-fiber reinforced plastic (CFRP). Feed rate was found as the predominant factor on the drilling outputs. Abrasive wear was observed on both flank and relief surfaces, which created edge wear on cutting edges. No sign of chipping or plastic deformation has been observed on the surfaces of drills. © 2012 The Author(s).

Cyclic nanoindentation and nano-impact fatigue characterisation of functionally graded TiN/TiNi shape memory film

This paper investigates the mechanism of nanoscale fatigue of functionally graded TiN/TiNi films using nano-impact and multiple-loading-cycle nanoindentation tests. The functionally graded films were deposited on silicon substrate, in which TiNi films maintain shape memory and pseudo elastic behavior, while a modified TiN surface layer provides tribological and anti-corrosion properties. Nanomechanical tests were performed to comprehend the localized film performance and failure modes of the functionally graded film using NanoTestTM equipped with Berkovich and conical indenter between 100 μN to 500 mN loads. The loading mechanism and load history are critical to define film failure modes (i.e. backward depth deviation) including the shape memory effect of the functionally graded layer. The results are sensitive to the applied load, loading type (e.g. semi-static, dynamic) and probe geometry. Based on indentation force-depth profiles, depth-time data and post-test surface observations of films, it is concluded that the shape of the nanoindenter is critical in inducing the localized indentation stress and film failure, including shape recovery at the lower load range. Elastic-plastic finite element (FE) simulation during nanoindentation loading indicated that the location of subsurface maximum stress near the interface influences the backward depth deviation type of film failure. A standalone, molecular dynamics simulation was performed with the help of a long range potential energy function to simulate the tensile test of TiN nanowire with two different aspect ratios to investigate the theory of its failure mechanism.

First comprehensive peat depositional records for tin, lead and copper associated with the antiquity of Europe's largest cassiterite deposits

Tin, as a constituent of bronze, was central to the technological development of early societies, but cassiterite (SnO2) deposits were scarce and located distantly from the centres of Mediterranean civilizations. As Britain had the largest workable ore deposits in the ancient Western world, this has led to much historical speculation and myth regarding the long-distance trading of tin from the Bronze Age onwards. Here we establish the first detailed chronology for tin, along with lead and copper deposition, into undisturbed ombrotrophic (rain-fed) peat bogs located at Bodmin Moor and Dartmoor in the centre of the British tin ore fields. Sustained elevated tin deposition is demonstrated clearly, with peaks occurring at 100-400 and 700-1000 calendar years AD - contemporaneous with the Roman and Anglo-Saxon periods respectively. While pre-Roman Iron Age tin exploitation undoubtedly took place, it was on a scale that did not result in convincingly enhanced deposition of the metal. The deposition of lead in the peat record provides evidence of a pre-Roman metal-based economy in southwest Britain. Emerging in the 4th century BC, this was centred on copper and lead ore processing that expanded exponentially and then collapsed upon Roman colonization during the 1st century AD. (C) 2011 Elsevier Ltd. All rights reserved.

Determining the Effect of Plasma Pre-Treatment on Antimony Tin Oxide to Support Pt@Pd and the Oxygen Reduction Reaction Activity

This article reveals the effect of plasma pre-treatment on antimony tin oxide (ATO) nanoparticles. The effect is to allow Pt@Pd to be deposited homogeneously on the ATO surface with high dispersion and narrow particle size distribution. The Pt@Pd core–shell catalyst was prepared using the polyol method and shows a dramatic improvement towards ORR activity and durability.

Utilização de redes TIN em modelos distribuídos de precipitação/escoamento superficial

A comunicação apresenta as directivas de desenvolvimento de um modelo distribuído e a sua aplicação à Ribeira da Pradiela (distrito de Évora, afluente do Dejebe). A utilização de modelos distribuídos de precipitação/escoamento superficial para modelação integrada dos fenómenos hidrodinâmicos, transporte de sedimentos e qualidade da água à escala da bacia hidrográfica, é fundamental para uma correcta percepção dos binómios causas/efeitos e consequente gestão optimizada dos recursos hídricos. Os modelos distribuídos existentes assentam em malhas estruturadas de células regulares adjacentes (DEM) ou em malhas de triângulos irregulares adjacentes (TIN). Os primeiros têm um processamento relativamente simples e são compatíveis com a estrutura matricial de uma imagem raster, contudo obrigam a uma densidade de informação uniforme sobre a área em estudo, apresentam problemas de escala na representação das linhas de água e das variáveis distribuídas como a altitude, classes de solo, classes de uso do solo, dotações de rega, fertilizantes e pesticidas. As redes TIN são mais versáteis e no caso particular de os pontos levantados sobre o terreno formarem uma métrica regular, a rede TIN representa uma malha estruturada. Os modelos existentes que utilizam uma malha TIN definem a rede hidrográfica pelas arestas comuns dos triângulos que formam um ângulo côncavo entre si. Esta implementação pode forçar a existência de linhas de água onde não existem traços morfológicos da sua existência. A metodologia proposta para gerar as linhas de água passa por definir uma área de influência associada a cada nó (polígono de Voronoi) que drena por uma linha de água definida entre o próprio nó e o nó vizinho com o qual forma o maior declive. Esta metodologia é relativamente simples, não cria ambiguidades e permite criar uma rede hidrográfica cuja estrutura é perfeitamente compatível com a implementação de um algoritmo de diferenças finitas. As secções transversais das linhas de água são definidas como função da área a montante da respectiva secção. A precipitação efectiva é calculada à escala da bacia pelo método da curva número (CN) do Soil Conservation Service (SCS) e à escala de uma parcela pela equação de Richardson. O escoamento é resolvido pela equação da onda cinemática nas linhas de água de ordem superior, pela equação de conservação da massa nas depressões e pelas equações de Saint-Venant na linha de água principal. É considerado o destacamento nas encostas e o destacamento/ transporte/ deposição nas linhas de água. Também é considerado o transporte de poluentes adsorvidos aos sedimentos, bem como fenómenos de wash-off .

Traduzir Teatro no Estado Novo: Gata em Telhado de Zinco Quente (1959), tradução de Sérgio Guimarães, do original Cat on a Hot Tin Roof (1955), de Tennessee Williams

À luz da viragem cultural dos Estudos de Tradução ocorrida nos anos 80 e tendo em conta a interdisciplinaridade abordada nos campos literário, cultural e histórico pela Manipulation School (Lefevere, Bassnett, Lambert, Hermans e Toury), na esteira de Itamar Even-Zohar com a Teoria dos Polissistemas (1979), a presente dissertação pretende analisar a tradução portuguesa da peça Cat on a Hot Tin Roof (1955), da autoria de Tennessee Williams, intitulada Gata em Telhado de Zinco Quente (1959), de Sérgio Guimarães. Este pode ser um caso representativo de como a tradução para teatro actua na cultura receptora numa perspectiva diatópica, antevendo a dimensão intercultural da tradução para o palco. É ao tradutor que cabe a tarefa de transferir a peça de um sistema linguístico e cultural para outro, conhecendo, se possível, o grau de representabilidade da mesma e o contexto cultural de chegada. Deste modo, é evidenciada a competência artístico-criativa do tradutor teatral que trabalha com o intuito de manter, fidus interpres, as intenções do autor da obra original. No período em que Cat on a Hot Tin Roof foi escrita, ensombrado pelo controlo sociopolítico do Macartismo nos E.U.A. e o contexto em que a tradução foi concretizada, sob a vigência da Ditadura de Salazar, a (auto)censura desempenha um papel fundamental ao moldar a produção literária nos dois sistemas culturais. Numa época em que, mais do que nos dias de hoje, traduzir consistia numa actividade subserviente e secundária, Vasco Morgado, detentor do monopólio de teatros em Lisboa encomendou a Sérgio Guimarães a tradução de uma peça de Tennessee Williams. Com base na teoria desenvolvida por Lawrence Venuti em The Translator’s Invisibility (1995), não é despiciente problematizar, neste estudo de caso, a invisibilidade do tradutor/mediador entre o texto e a representação, abordando simultaneamente as estratégias então necessárias para a peça ser aprovada e posta em cena.