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Yi‐Shen Zhu Alan Connolly Anders Guyon Richard J. FitzGerald 《International Journal of Food Science & Technology》2014,49(6):1600-1606
Marine minerals are a potential source of calcium and magnesium for nutritional supplementation. This study analysed the solubilisation of calcium and magnesium from the skeletal remains of Lithothamnion calcareum. Scanning electron microscopy analysis demonstrated a nonporous microstructure. Spectrophotometric determination showed that the calcium and magnesium contents were 30.01 and 6.22% (w/w), respectively. Solubilisation of calcium and magnesium was highly pH dependent. The temperature‐dependent solubilisation of calcium fitted the shrinking core model. The apparent activation energy for calcium solubilisation was 28.6 kJ mol?1. Inclusion of caseinophosphopeptides (CPPs), casein‐derived mineral binding peptides, during the solubilisation of calcium and magnesium appeared to decrease the extent of calcium solubilisation at pH 6.0 and 8.0. The results herein have implications for the choice of optimal pH conditions for the sustained release of calcium and magnesium from marine mineral sources. 相似文献
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Young men from poorer backgrounds are associated with high road traffic collision levels. However, solving this problem has proven very difficult. Hence this paper summarises the findings of a UK government funded two-year trial of a cross-discipline intervention to reduce aggressive driving amongst this group. 相似文献
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Kleitos Panagi Christian J. Laycock James P. Reed Alan J. Guwy 《International Journal of Hydrogen Energy》2021,46(2):2630-2645
Biohythane is typically composed of 60/30/10 vol% CH4/CO2/H2 and can be produced via two-stage anaerobic digestion of renewable and low carbon biomass with much greater efficiency compared with CH4/CO2 biogas. This work investigates the effects of fuel variability on the electrical performance and fuel processing of a commercially available anode supported solid oxide fuel cell (SOFC) operating on biohythane mixtures at 750 °C. Cell electrical performance was characterised using current-voltage curves and electrochemical impedance spectroscopy. Fuel processing was characterised using quadrupole mass spectroscopy. It is shown that when H2/CO2 is blended with CH4 to make biohythane, the SOFC efficiency is significantly increased, high SOFC durability is achieved, and there are considerable savings in CH4 consumption. Enhanced electrical performance was due to the additional presence of H2 and promotion of CH4 dry reforming, the reverse Boudouard and reverse water-gas shift reactions. These processes alleviated carbon deposition and promoted electrochemical oxidation of H2 as the primary power production pathway. Substituting 50 vol% CH4 with 25/75 vol% H2/CO2 was shown to increase cell power output by 81.6% at 0.8 V compared with pure CH4. This corresponded to a 3.4-fold increase in the overall energy conversion efficiency and a 72% decrease in CH4 consumption. A 260 h durability test demonstrated very high cell durability when operating on a typical 60/30/10 vol% CH4/CO2/H2 biohythane mixture under high fuel utilisation due to inhibition of carbon deposition. Overall, this work suggests that decarbonising gas grids by substituting natural gas with renewably produced H2/CO2 mixtures (rather than pure H2 derived from fossil fuels), and utilising in SOFC technology, gives considerable gains in energy conversion efficiency and carbon emissions savings. 相似文献
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Alan Cottey 《AI & Society》2014,29(2):249-257
Radical changes of our cultural values in the near future are inevitable, since the current culture is ecologically unsustainable. The present proposal, radical as it may seem to some, is accordingly offered as worthy of consideration. The main section of this article is on a proposed scheme, named Asset and Income Limits, for instituting maxima to the legitimate incomes and assets of individuals. This scheme involves every individual being associated with two bank accounts, an asset account (their own property) and a holding account (held in escrow). Other parts of the advocated change in economic landscape are a radically different understanding of the concept of work and the introduction of a basic income. The roles of technology and culture, in creating both the opportunities and the obstacles to a transformation of society, are discussed. Non-monetary, non-convertible rewards for exceptional contributions to society are described. The scheme enhances freedom, being neutral in relation to many other value systems, such as the secular/sacred spectrum. The qualitative versus quantitative dichotomy is addressed, and it is concluded that the most that can be said of a just and sustainable society that has yet to be created is that the maximum income should be no more than one order of magnitude greater than the basic income, that is ~10 times at the most. Incentives for profitable employment would still be sufficient, and paying the basic income out of taxes on sales and/or non-basic income would be feasible. 相似文献
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Alan Trachtenberg 《History of Photography》2013,37(2):178-181
Abstract The coffee-table is where Faces looks as if it belongs. A weighty package of 540 expensively produced pages, with 380 duo-tone reproductions, the book exudes a familiar slickness. But, as often with photographs themselves, the surface impression misleads. Ben Maddow's text is no mere accompaniment to the pictures. Winding among the landmarks of photographic history, the text vies in interest with the images; the text too is an artful performance. This alone gives this otherwise overproduced book high marks. Intelligent and interesting (let alone artful) writing about photographs, especially in the presence of images powerful enough to threaten speech with the charge of impertinence, is rare indeed. Novelist, poet, film maker, Maddow here undertakes ‘a narrative history’ of faces in photography, and while the history itself holds no surprises, the sheer facility and alertness of the writing keeps the text always slightly ahead of the pictures The writing dominates the book, all appearances to the contrary notwithstanding, and that is a welcome change in photography publications. 相似文献
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Bibliometric analysis of publication metadata is an important tool for investigating emerging fields of technology. However, the application of field definitions to define an emerging technology is complicated by ongoing and at times rapid change in the underlying technology itself. There is limited prior work on adapting the bibliometric definitions of emerging technologies as these technologies change over time. The paper addresses this gap. We draw on the example of the modular keyword nanotechnology search strategy developed at Georgia Institute of Technology in 2006. This search approach has seen extensive use in analyzing emerging trends in nanotechnology research and innovation. Yet with the growth of the nanotechnology field, novel materials, particles, technologies, and tools have appeared. We report on the process and results of reviewing and updating this nanotechnology search strategy. By employing structured text-mining software to profile keyword terms, and by soliciting input from domain experts, we identify new nanotechnology-related keywords. We retroactively apply the revised evolutionary lexical query to 20 years of publication data and analyze the results. Our findings indicate that the updated search approach offers an incremental improvement over the original strategy in terms of recall and precision. Additionally, the updated strategy reveals the importance for nanotechnology of several emerging cited-subject categories, particularly in the biomedical sciences, suggesting a further extension of the nanotechnology knowledge domain. The implications of the work for applying bibliometric definitions to emerging technologies are discussed. 相似文献