92 research outputs found

    The quest for companions to post-common envelope binaries: I. Searching a sample of stars from the CSS and SDSS

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    As part of an ongoing collaboration between student groups at high schools and professional astronomers, we have searched for the presence of circum-binary planets in a bona-fide unbiased sample of twelve post-common envelope binaries (PCEBs) from the Catalina Sky Survey (CSS) and the Sloan Digital Sky Survey (SDSS). Although the present ephemerides are significantly more accurate than previous ones, we find no clear evidence for orbital period variations between 2005 and 2011 or during the 2011 observing season. The sparse long-term coverage still permits O-C variations with a period of years and an amplitude of tens of seconds, as found in other systems. Our observations provide the basis for future inferences about the frequency with which planet-sized or brown-dwarf companions have either formed in these evolved systems or survived the common envelope (CE) phase.Comment: accepted by A&

    Land Law, Property Ideologies and the British-Irish relationship

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    English and Irish land law are deeply influenced by the historical context of the British-Irish relationship, yet property scholarship comparing the two jurisdictions is surprisingly rare. The current Brexit negotiations provide a timely reminder of the strategic importance of property and trade relations between the two countries; and of their related-but-different legal cultures. In this article we examine how the property cultures of England and Ireland were shaped by the politics and practices of land tenure, by competing economic and property ideologies, and by the influence of both on national identity and statehood in both jurisdictions. The article reveals the role of local contexts and events in shaping land reform, and demonstrates the fertile potential of the comparative frame to contextualise each jurisdiction’s doctrines and practices. As domestic land law systems are drawn together in the context of emerging EU jurisdiction over areas like mortgage credit, each jurisdiction’s underpinning ideological commitments have important implications for the ease – or not – of attempts to harmonize member state practices. We explain the alignments and divergences between domestic underpinnings of Irish and English law, and reflect on the implications of our findings for contemporary property problems in the context of evolving economic and political relationships between the UK and Ireland

    Compósito para a construção civil a partir de resíduos industriais

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    RESUMO Os estudos que visam à utilização dos resíduos industriais vêm se intensificando diante da pressão das organizações ambientais, escassez de recursos naturais, busca de certificações para ganho de mercado e minimização de impacto ambiental. O presente trabalho desenvolveu um novo compósito a base de resíduos industriais como cinzas de madeira, lodo de estação de tratamento de água (ETA) e resíduos de produção de cal com propriedades mecânicas que atendem às exigências da ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS - NBR 15270-1/2005, NBR 15270-2/2005 e NBR 5739/2007, objetivando a sua utilização na construção civil sem o acréscimo de cimento Portland. As resistências à compressão variaram de 2,35 a 16,48 MPa. O índice de absorção de água das amostras testadas também atendeu às normas aplicadas, demonstrando que ao longo do tempo de cura houve diminuição da porosidade com possível hidratação da cal. Os resultados do ensaio de resistência à compressão apresentaram variações durante o tempo de cura que podem ser justificadas pela presença de material orgânico no lodo de ETA e pelo tamanho das partículas de cinza de madeira que durante a homogeneização não foram destruídas completamente. Apesar das variações observadas nos resultados, as resistências dos compósitos se enquadram na classificação para blocos cilíndricos de concreto e blocos cerâmicos para alvenaria

    The Early Royal Society and Visual Culture

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    Recent studies have fruitfully examined the intersection between early modern science and visual culture by elucidating the functions of images in shaping and disseminating scientific knowledge. Given its rich archival sources, it is possible to extend this line of research in the case of the Royal Society to an examination of attitudes towards images as artefacts –manufactured objects worth commissioning, collecting and studying. Drawing on existing scholarship and material from the Royal Society Archives, I discuss Fellows’ interests in prints, drawings, varnishes, colorants, images made out of unusual materials, and methods of identifying the painter from a painting. Knowledge of production processes of images was important to members of the Royal Society, not only as connoisseurs and collectors, but also as those interested in a Baconian mastery of material processes, including a “history of trades”. Their antiquarian interests led to discussion of painters’ styles, and they gradually developed a visual memorial to an institution through portraits and other visual records.AH/M001938/1 (AHRC
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