Changes in internal temperatures within the built environment as a response to a changing climate

In August 2003, 14,800 heat-related deaths occurred in Paris [1] during what is considered the warmest summer since at least 1500 2, 3, 4 and 5. These deaths resulted not only from unusually high peak temperatures and a reduction in the diurnal temperature swing, but also from a failure of buildings to successfully modify the external environment. It has been estimated [6] that by the 2040s, a 2003-type summer is predicted to be average within Europe. Clearly this will have a great impact on morbidity and mortality and produce challenges for emergency services [7]. The effects of climate change on the internal environment are not well known and are the subject of much current research [8]. For building scientists and emergency planners, there is the need to know the general form of the relationship between increases in external temperature due to climate change and increases in internal temperatures. Here we show that the relationship is linear, and that differing architectures give rise to differing constants of proportionality. This is a surprising result as it had been assumed that, given the complexity of the heat flows within large structures, no simple relationship would exist and had not been found in previous work [9]. We term these constants of proportionality climate change amplification coefficients. These coefficients fully describe the change in the internal environment of an architecture given a seasonal or annual change in external climate and can be used to judge the resilience to climate change of a particular structure. The estimation and use of these coefficients for new or existing buildings will allow: the design of more resilient buildings adapted to a changing climate, cost-benefit analysis of refurbishment options and the rational assembly of at-risk registers of vulnerable building occupants.     

A study of nucleation and the early stage of growth of nickel powder from a vapour nickel carbonyl precursor

The phenomenon of nucleation of solid particles from the gas phase has a number of important industrial applications. In this study, the formation of nickel nuclei from the gas phase decomposition of nickel carbonyl has been predicted using classical nucleation theory and compared with experimental results from a hot wall tube reactor. It was shown that the free energy nucleation barrier was much less significant in reality than predicted by theory. In one instance, application of the classical theory suggested that the nucleation onset temperature should be more than 250 K higher than the onset temperature calculated from the volume free energy. The experimental results showed that the actual nucleation onset temperature was increased by less than 60 K. Further calculations showed that the observed primary particles were produced during a brief nucleation event, and that the major contribution to particle growth was the result of the surface reaction.     

Simultaneous reduction and carburization of ilmenite

Western Australian ilmenite was reduced using “Collie” coal at temperatures in the range 1587 to 1790 K to form carbon-saturated iron and titanium oxycarbide. The oxycarbide phase formed from Ti₃O₅ at temperatures below 1686 K and from Ti₂O₃ at temperatures above 1686 K. At 1686 K, both mechanisms occurred. The reaction rate was controlled by oxidation of carbon by carbon dioxide generated by reduction of the oxide phase. The final product at temperatures up to 1686 K was a fine dispersion of titanium oxycarbide in iron. At 1790 K, the reducing oxide tended to remain intact and formed a coarser distribution. In general, manganese impurities from the ilmenite were confined to the iron phase in the product, although some of the coarser oxycarbide particles formed at 1790 K contained trapped manganese at the internal pores.     

Green fluorescent antibodies: novel in vitro tools

We produced a fluorescent antibody as a single recombinant proteinin Escherichia coli by fusing a red-shifted mutant of greenfluorescent protein (EGFP) to a single-chain antibody variablefragment (scFv) specific for hepatitis B surface antigen (HepBsAg).GFP is a cytoplasmic protein and it was not previously knownwhether it would fold correctly to form a fluorescent proteinin the periplasmic space of E.coli. In this study we showedthat EGFP alone or fused to the N'- and C'-termini of the scFvresulted in fusion proteins that were in fact highly fluorescentin the periplasmic space of E.coli cells. Further characterizationrevealed that the periplasmic N'-terminal EGFP–scFv fusionwas the most stable form which retained the fluorescent propertiesof EGFP and the antigen binding properties of the native scFv;thus representing a fully functional chimeric molecule. We alsodemonstrated the utility of EGFP–scFv in immunofluorescencestudies. The results showed positive staining of COS-7 cellstransfected with HepBsAg, with comparable sensitivity to a monoclonalantibody or the scFv alone, probed with conventional fluorescein-labelledsecond antibodies. In this study, we developed a simple techniqueto produce fluorescent antibodies which can potentially be appliedto any scFv. We demonstrated the utility of an EGFP–scFvfusion protein for immunofluorescence studies, but there aremany biological systems to which this technology may be applied.