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231.
Catalysis Letters - Developing biomass-based strategies for liquid bio-fuels production is promising for the reduction of the aftereffects of fossil fuels. The conversion of lignin-derived...  相似文献   
232.
Bipolar plates (BPs) are key components of Proton Exchange Membrane Fuel Cells mainly employed in hydrogen-powered electric vehicles. Here, a reliable and detailed experimental method to prepare graphite-epoxy composites suitable for manufacturing BPs is reported. Dry and wet mixing procedures were compared and a simple composition was optimized, with regard to electrical conductivity. The adoption of wet mixing of the components and the choice of the conductive filler were the main factors that contributed to the achievement of good electrical and mechanical properties. The addition of a small percentage of carbon black as a secondary filler was also advantageous. The effects of molding parameters (pressure, temperature and time) on a fixed-composition graphite-epoxy composite were modeled using a Design Of Experiments approach, which provided valuable information for future improvements. Conductivity values well above the US DOE requirements were obtained.  相似文献   
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Opisthobranchs belong to a subclass of highly evolved and specialised marine gastropods that rely on the use of secondary metabolites for their survival. Here we report the full elucidation of the biosynthesis of aromatic metabolites, lignarenones, in one of these gastropods, the cephalaspidean Scaphander lignarius. Feeding experiments with (2) H- and (13) C-labelled precursors revealed a mixed acetate/propionate polyketide pathway primed by benzoic acid. Phenylalanine ammonia lyase (PAL), unprecedented in animals, is central to the synthesis of this aromatic precursor by oxidative deamination of L-phenylalanine to cinnamic acid. Lignarenones are synthesised in the cytoplasm of specialised eukaryotic cells named Blochmann's glands, which are distributed in biosynthetic tissue localised in the vulnerable mantle of the mollusc. This result supports the hypothesis that this lineage of gastropods has acquired the genetic information to produce the chemical substances that they use for their survival.  相似文献   
235.
Label-free relative quantitative proteomics is a powerful tool for the survey of protein level changes between two biological samples. We have developed and applied an algorithm using chromatographic alignment of microLC-MS runs to improve the detection of differences between complex protein mixtures. We demonstrate the performance of our software by finding differences in E. coli protein abundance upon induction of the lac operon genes using isopropyl beta-D-thiogalactopyranoside. The use of our alignment gave a 4-fold decrease in mean relative retention time error and a 6-fold increase in the number of statistically significant differences between samples. Using a conservative threshold, we have identified 5290 total microLC-MS regions that have a different abundance between these samples. Of the detected difference regions, only 23% were mapped to MS/MS peptide identifications. We detected 74 proteins that had a greater relative abundance in the induced sample and 21 with a greater abundance in the uninduced sample. We have developed an effective tool for the label-free detection of differences between samples and demonstrate an increased sensitivity following chromatographic alignment.  相似文献   
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Mo.nalis.a is a conceptual model aimed at identifying the most suitable local geothermal sources to match the nearest industrial thermal needs. The methodological approach proposed is based on investigating industrial thermal processes and then identifying suitable geothermal solution plants that match these thermal requirements. The model was tested in Apulia (southern Italy) as a case study for assessing how the methodology could contribute to reducing the use of conventional energy resources for the industrial heat supply sector. The medium thermal needs in Apulia are always higher than 60 °C, and the main strategic industrial processes discussed into this work are “pasta and flour production” “wastewater treatment/sludge digestion” and “swimming pool management”. In order to match these industrial thermal demands, the most suitable proposed plant is the ground water heat pump system, limited to the first 100 m, the depth involved in the heat exchange through vertical probes of model. Finally, Mo.nalis.a identifies the Apulian areas with a possible development of these three activities using geothermal resource: the Foggia province, Murge and Salento sectors.  相似文献   
238.
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