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1.
Liquid phase pyrolysis (LPP) oil, an intermediate from biofuel production using second‐generation biomass, is a promising source of biobased platform chemicals like acetic acid, however, displaying a complex, multicomponent mixture. Reactive extraction with Cyanex®923 was investigated for selective recovery of acids and subsequent solvent regeneration in distillation at 200 mbar. In a three‐stage extraction 81 % of acids were removed from the LPP oil without loss of Cyanex®923 to the raffinate. Solvent regeneration efficiency of acids was up to 99.7 % with mainly acids and water in the distillate.  相似文献   
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Within the framework of the MABMEM research project, new high‐performance membranes are being developed for sustainable water management. The performance of the membranes will be evaluated in comparative and standardized fouling tests as well as in terms of the removal of trace impurities on a laboratory scale. Seven candidates are currently being tested in demonstrator trials with real‐water matrix in a waterworks for the direct treatment of dam water without prior coagulation over a period of 6 months. Subsequently, the new membrane materials will be operated with the effluent of a wastewater treatment plant.  相似文献   
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Managing the electricity network through ‘smart grid’ systems is a key strategy to address challenges of energy security, low carbon transitions and the replacement of ageing infrastructure networks in the UK. Small and medium enterprises (SMEs) have a significant role in shaping patterns of energy consumption. Understanding how their activities interrelate with changes in electricity systems is critical for active network management. A significant challenge for the transformation of electricity systems involves comprehending the complexity that stems from the variety of commercial activities and diversity of social and organizational practises among SMEs that interact with material infrastructures. We engage with SMEs to consider how smart grid interventions ‘fit’ into everyday operational activities. Drawing on analysis of empirical data on electricity use, smart metre data, surveys, interviews and ‘energy tours’ with SMEs to understand lighting, space heating and cooling, refrigeration and IT use, this paper argues for experimenting with the use of practise theory as a framework for bringing together technical and social aspects of energy use in SMEs. This approach reveals that material circumstances and temporal factors shape current energy demand among SMEs, with ‘connectedness’ an emergent factor.  相似文献   
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Objective: The purpose of this study was to investigate and quantify flow properties, compressibility, and compactibility of various pharmaceutical lactose powders found on the market today (DCL-11, DCL-21, M‐200, Flowlac-100, and Tablettose 70, 80, and 100). Methods: Flow properties were estimated by measuring flow time, angle of repose, and the Hausner ratio. Particle rearrangement was studied using Kawakita's linear model. Compressibility was studied using two ‘out-of-die’ methods: (i) the Heckel model and (ii) a modified Walker model. Compactibility was quantified using two methods: (i) the tensile strength profile (Cp) and (ii) the compactibility factor (Pr). Statistical approach was used to analyze the results. Results: Flow properties of all materials were passable or better, except for M-200, which has very poor flowability. Compressibility results demonstrated that the most compressible lactose is spray-dried grade of lactose (Flowlac-100) and the least compressible is milled lactose (M-200). Compactibility studies showed that β‐lactose (DCL-21) forms tablets with superior tensile strength in comparison with α-lactose. Conclusion: Results of the compressibility study showed that the discriminative power of modified Walker model is greater in comparison with Heckel model. Compactibility methods yield similar and comparable results.  相似文献   
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With the aim of investigating the technical feasibility of fuelling a conventional BWR (Boiling Water Reactor) with thorium-based fuel, computer simulations were carried out in a 2D infinite lattice model using CASMO-5. Four different fissile components were each homogenously combined with thorium to form mixed oxide pellets: Uranium enriched to 20% U-235 (LEU), plutonium recovered from spent LWR fuel (RGPu), pure U-233 and a mixture of RGPu and uranium recovered from spent thorium-based fuel. Based on these fuel types, four BWR nuclear fuel assembly designs were formed, using a conventional assembly geometry (GE14-N). The fissile content was chosen to give a total energy release equivalent to that of a UOX fuel bundle reaching a discharge burnup of about 55 MWd/kgHM. The radial distribution of fissile material was optimized to achieve low bundle internal radial power peaking. Reactor physical parameters were computed, and the results were compared to those of reference LEU and MOX bundle designs. It was concluded that a viable thorium-based BWR nuclear fuel assembly design, based on any of the fissile components, can be achieved. Neutronic parameters that are essential for reactor safety, like reactivity coefficients and control rod worths, are in most cases similar to those of LEU and MOX fuel. This is also true for the decay heat produced in irradiated fuel. However when Th is mixed with U-233, the void coefficient (calculated in 2D) can be positive under some conditions. It was concluded that it is very difficult to make savings of natural uranium by mixing LEU (20% U-235) homogenously with thorium and that mixing RGPu with thorium leads to more efficient consumption of Pu compared to MOX fuel.  相似文献   
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The MEGAPIE project aimed to design, build and operate a liquid metal spallation neutron target of about 1 MW beam power in the SINQ facility at the Paul Scherrer Institut (Villigen, Switzerland). This project is an important step in the roadmap towards the demonstration of the accelerator driven system (ADS) concept and high power liquid metal targets in general. Following the design phase, an experimental program was defined to provide a complete characterization of the facility by performing a “mapping” of the neutron flux at different points, from the center of the target to the beam lines. The neutronic performance of the target was studied using different experimental techniques with the goals of validating the Monte Carlo codes used in the design of the target; additionally, the performance was compared with the solid lead targets used before and after the MEGAPIE experiment.  相似文献   
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Under environmental conditions, wild birds can be exposed to multiple stressors including natural toxins, anthropogenic pollutants and infectious agents at the same time.This experimental study was successful in testing the hypothesis that adverse effects of cyanotoxins, heavy metals and a non-pathogenic immunological challenge combine to enhance avian toxicity. Mortality occurred in combined exposures to naturally occurring cyanobacterial biomass and lead shots, lead shots and Newcastle vaccination as well as in single lead shot exposure. Mostly acute effects around day 10 were observed. On day 30 of exposure, there were no differences in the liver accumulation of lead in single and combined exposure groups. Interestingly, liver microcystin levels were elevated in birds co-exposed to cyanobacterial biomass together with lead or lead and the Newcastle virus. Significant differences in body weights between all Pb-exposed and Pb-non-exposed birds were found on days 10 and 20. Single exposure to cyanobacterial biomass resulted in hepatic vacuolar dystrophy, whereas co-exposure with lead led to more severe granular dystrophy. Haematological changes were associated with lead exposure, in particular. Biochemical analysis revealed a decrease in glucose and an increase in lactate dehydrogenase in single and combined cyanobacterial and lead exposures, which also showed a decreased antibody response to vaccination.The combined exposure of experimental birds to sub-lethal doses of individual stressors is ecologically realistic. It brings together new pieces of knowledge on avian health. In light of this study, investigators of wild bird die-offs should be circumspect when evaluating findings of low concentrations of contaminants that would not result in mortality on a separate basis. As such it has implications for wildlife biologists, veterinarians and conservationists of avian biodiversity.  相似文献   
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Because of multimedia's structure and complexity, security mechanisms for multimedia data should be specific for each purpose. We introduce the most important security requirements for all types of multimedia systems. We also survey revocation methods for digital certificates and introduce a media-independent classification scheme  相似文献   
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