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A cradle-to-grave life cycle assessment (LCA) is performed to compare nanosilver T-shirts with conventional T-shirts with and without biocidal treatment. For nanosilver production and textile incorporation, we investigate two processes: flame spray pyrolysis (FSP) and plasma polymerization with silver co-sputtering (PlaSpu). Prospective environmental impacts due to increased nanosilver T-shirt commercialization are estimated with six scenarios. Results show significant differences in environmental burdens between nanoparticle production technologies: The "cradle-to-gate" climate footprint of the production of a nanosilver T-shirt is 2.70 kg of CO(2)-equiv (FSP) and 7.67-166 kg of CO(2)-equiv (PlaSpu, varying maturity stages). Production of conventional T-shirts with and without the biocide triclosan has emissions of 2.55 kg of CO(2)-equiv (contribution from triclosan insignificant). Consumer behavior considerably affects the environmental impacts during the use phase. Lower washing frequencies can compensate for the increased climate footprint of FSP nanosilver T-shirt production. The toxic releases from washing and disposal in the life cycle of T-shirts appear to be of minor relevance. By contrast, the production phase may be rather significant due to toxic silver emissions at the mining site if high silver quantities are required. 相似文献
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The economic impacts on developing regions following a global cap and trade system for carbon dioxide are assessed through the use of an energy-economy systems model. Both an equal per capita allocation and a contraction and convergence allocation with convergence of the per capita emissions by 2050 are shown to offer economic incentive for Africa, India and probably also Latin America to accept binding emissions commitments under a 450 ppm carbon dioxide stabilization scenario. The gain for Latin America is mainly a result of increased export revenues from sales of bio-fuels as a result of the climate policy. It is, on the other hand, unlikely that these allocation approaches would offer an economic incentive for China to join the regime because of its high economic growth, present higher per capita emissions than India and Africa, and more costly mitigation options than Latin America. A more stringent allocation for developing countries such as contraction with convergence of the per capita emissions by the end of this century is estimated to generate reduced net gains or increased net losses for the developing regions (though Africa is still expected to gain). 相似文献
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Direct injection of samples on high-resolving mass spectrometers is an effective way to maximize analytical throughput and yet allow analyte discrimination in complex samples by mass-to-charge ratio. We present a platform of flow injection electrospray-time-of-flight mass spectrometry to profile small molecules in >1400 biological extracts per day at native mass resolution. We comprehensively benchmark the performance with more than 5000 injections of chemically defined standards and Escherichia coli cellular extracts obtained from miniscale cultivations. For at least 90% of tested compounds, we attain a linear response over 3 decades of concentration, interday coefficient of variation of <20%, and a mass accuracy of <0.001 amu. In polar Escherichia coli fractions, we reproducibly detected >1500 distinct ions in each mode. The accurate mass and correlation analysis enabled one to assign with good confidence 400-800 ions to electrospray derivatives of metabolites listed in the genome-wide reconstruction of Escherichia coli metabolism. Hence, we attain a coverage of about one-quarter of the total number of compounds listed in the reconstruction. Finally, we present an exemplary screen with Escherichia coli deletion mutants to show the exquisite capacity of the platform to identify lesions in primary metabolism at high throughputs. 相似文献
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阿联酋新的生态城市广场上,巨大的伞状物提供了可移动的阴凉,同时白天储存热量,夜晚将其释放。这一基于向日葵特性的伞状物创意,使得LAVA一举赢得了国际竞赛。Masdar是阿联酋第一个零碳排放、零污染的城市,距阿布扎比17km,预计将由7期建成。 相似文献
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