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Mechanochemical-Assisted Leaching of Lamp Phosphors： A Green Engineering Approach for Rare-Earth Recovery

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Engineering 2018年第3期4卷 398-405页

作者： Steff Van Loy koen Binnemans Tom Van Gerven Department of Chemical Engineering KU Leuven Heverlee B-3001 Belgium Department of Chemistry KU Leuven Heverlee B-3001 Belgium

Rare-earth elements （REEs） are essential metals for the design and development of sustainable energy applications, Recycling these elements from waste streams enriched in them is crucial for securing an independent future supply for sustainable applications, This study compares the mechanisms of mechan- ical activation prior to a hydrometallurgical acid-leaching process and a solvometallurgical mechanochemical leaching process for the recovery of REEs from green lamp phosphor, LaPO4：Ce3＋, Th3＋, After 60 min of processing time, the REE leaching rates showed a significant enhancement of 60% after cycled mechanical activation, and 98% after the combined mechanochemical leaching process, High-resolution transmission electron microscopy （HR-TEM） imaging disclosed the cause for the improved REE leaching rates： The improved leaching and leaching patterns could he attributed to changes in the crystal morphology from monocrystalline to polycrystalline, Reduction of the crystallite size to the nanoscale in a polycrystalline material creates irregular packing of chemical units, resulting in an increase in defect-rich grain boundaries in the crystals, which enhances the leaching process, A solvometallurgical method was developed to combine the mechanical activation and leaching process into a single step, which is beneficial for operational cost, This results in an efficient and simple process that provides an alternative and greener recycling route for lamp phosphor waste,

关键词： Mechanochemistry Rare-earth elements Lamp phosphor waste Ball-milling Solvometallurgy

Effect of the Welding Parameters on the Structural and Mechanical Properties of Aluminium and Copper Sheet Joints by Electromagnetic Pulse Welding

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World Journal of Engineering and Technology 2016年第4期4卷 538-561页

作者： Irene Kwee Verena Psyk koen Faes Belgian Welding Institute Zwijnaarde Belgium Fraunhofer Institute for Machine Tools and Forming Technology Fraunhofer Institute Chemnitz Germany

Aluminium-copper hybrid parts, as a substitution to copper parts, result in weight and cost reduction, and are relevant in applications related to the electronic, heating and cooling sector. However, aluminium to copper joined by thermal welding processes presents challenges in terms of achieving good joint quality. This is attributed to their dissimilar mechanical and thermal properties which result in large stress gradients during heating. This study investigated joining of aluminium to copper sheets by electromagnetic pulse welding, which is a solid-state process that uses electromagnetic forces for joining of dissimilar materials. Hybrid sheet welds were obtained for all parameters conditions, selected according to a Taguchi L18 design. The structural and mechanical characteristics were examined and related to the welding parameters by means of a Pareto analysis and response graphs. The welded zone started with a wavy interface with interfacial layers and defects and evolved to a flat interface without interfacial layers. The maximum transferable force depended on the minimum specimen thickness and the strength of the hybrid sheet weld. In case of aluminium sheet thickness reduction, the maximum transferable force was linearly correlated with the aluminium sheet thickness. High quality joints were obtained for no aluminium sheet thickness reduction and for a sheet weld strength which was at least as high as that of the base material. The most effective way to increase the transferable force was to lower the initial gap and to increase the free length, which resulted in no aluminium sheet thickness reduction. Alternatively, the use of a rounded spacer decreased the effect of the aluminium sheet thickness on the transferable force. An increase in weld width was achieved for an increase in capacitor charging energy and gap, whereas an increase in weld length was obtained for a decrease in gap. An increase in weld width did not necessarily result in an increase in t

关键词： Electromagnetic Pulse Sheet Welding Aluminum-to-Copper Welds Dissimilar Metal Welds Transferable Force Interfacial Morphology

VLES Modelling with the Renormalization Group

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Journal of Thermal Science 2003年第4期12卷 328-331页

作者： Chris De Langhe rug.ac.be Bart Merci rug.ac.be koen Lodefier rug.ac.be Erik Dick rug.ac.be Ghent University Dept. of Flow Heat and Combustion Mechanics Sint-Pietersnieuwstraat 41 B-9000 Gent Belgium

In a Very-Large-Eddy Simulation (VLES), the filterwidth-wavenumber can be outside the inertial range, and simple subgrid models have to be replaced by more complicated (''RANS-like'') models which can describe the transport of the biggest eddies. One could approach this by using a RANS model in these regions, and modify the lengthscale in the model for the LES-regions. The problem with these approaches is that these models are specifically calibrated for RANS computations, and therefore not suitable to describe inertial range quantities. We investigated the construction of subgfid viscosity and transport equations without any calibrated constants, but these are calculated directly form the Navier-Stokes equation by means of a Renormalization Group (RG) procedure. This leads to filterwidth dependent transport equations and effective viscosity with the right limiting behaviour (DNS and RANS limits).

关键词： very-large-eddy simulation subgrid modellig k-εmodel.

SCM Implementation Decisions of Principal-Agent under Asymmetric Information

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Open Journal of Applied Sciences 2019年第4期9卷 159-171页

作者： Lina Wang Stephan Poelmans koen Milis Economy & Management School Hainan Normal University Haikou China Management School Liaoning University of Technology Jinzhou China Faculty of Economics and Management Hogeschool-Universiteit Brussel KULeuven Association Brussel Belgium Education Management Industry Campus Vesta Brussels Belgium

The optimization investment policy decision of SCM-Supply Chain Management-implementation has been analysed under symmetric and asymmetric information conditions. For both conditions, SCM implementation options’ decision optimizing models have been developed. In these models, both clients and vendors try to pursue their own benefits. Based upon the principal-agent theory, the models show to what extent a principal (a client) needs to pay more to an agent (a vendor) in a context of asymmetric information. For the client, it is important to understand the extra costs to be able to adopt effective strategies to stimulate a vendor to perform an optimal implementation of a SCM system. The results of a simulation experiment regarding SCM implementation options illustrate and verify the theoretical findings and confirm the general notion that the less informed party is obliged to pay information rent to the better-informed party.

关键词： SCM Implementation Problems Asymmetric Information Implementation Control Cost Evaluation Level Principal-Agent Theory

Sustainable urbanization: energy and environment in the Chongqing Municipality, China

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Journal of Chongqing University 2005年第4期4卷 199-207页

作者：李百战 koen Steermers Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment Under the Ministry of Education Chongqing University Chongqing 400030 P.R. China The Martin Center for Architectural and Urban Studies Department of Architecture University of Cambridge 6 Chaucer Road Cambridge CB2 2EB UK

Chongqing is the largest municipality under the Chinese Central Government (MCG) in terms of administrative area and population and is now the most important economic and cultural center of the upper Yangtze River and Three Gorges area. The Three Gorges Dam project, one of the largest world infrastructure projects, causes a great deal of immigration to Chongqing and results in the rapid urbanization of the city, and it has brought in a great deal of environmental impact, which is a global concerned issue. This paper introduces the city profile of Chongqing municipality and its urbanization impact on energy and environment. The demand and the trend of energy consumption in built environment (building and transport) have been analysed. The living environment of Chongqing residents and the local energy efficient policy have been introduced. Finally the authors discuss the key issues of the sustainable urban development of Chongqing.

关键词： energy and environment Chongqing urbanization building transport air pollution .

摆脱非传染性疾病的困扰-通过尽早注意健康饮食来预防!

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中国食品添加剂 2013年第S1期24卷 212-214页

作者： koen Van Praet BENEO亚太私人有限公司

人体是一个"灵活的"有机体,它能够应对正常情况和每天所遇到的挑战。人体也是一个非常复杂的生物系统。它具有消化、吸收、调节和反调节功能,能够改善和运行复杂的新陈代谢过程。

关键词：新陈代谢过程反调节 intestine 营养问题 osteoporosis 健康功效肠道菌群骨质疏松钙吸收菊粉

China’s Development of an Innovation-driven Economy-An Intermediate Assessment

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Innovation and Development Policy 2019年第2期1卷 85-103页

作者： Rainer Frietsch Henning Kroll koen Jonkers Fraunhofer Institute for Systems and Innovation Research Karlsruhe 76139Germany Institutes of Science and Development Chinese Academy of SciencesBeijing 100190China Leibniz University Hannover 30167Germany Joint Research Centre European CommissionBrussel 1050Belgium

China’s economic, technological and scientific achievements of the past years and decades are impressive. However, the country’s policy makers have even higher aspirations and therefore set up a number of policies to tackle the threat of the so-called middle-income-trap. This paper describes and discusses some of these policies, of which the Innovation-Driven Economy Development Strategy is seen as the backbone of current Chinese STI policy. The level of achievements as well as the expected developments is put into perspective by selected empirical data. We conclude that China’s industry will further improve its competitiveness in several sectors in the coming years. Western representatives need to wave good-bye to the ideas that China assimilates. At the same time, the era of the "land of gold" when China provides the world with low-cost products and buys high-tech goods from Western companies is over. However, if China intends to become a reputable member of the international STI community, the country should develop actively the nowadays often-demanded ‘level-playing field’. This would not only mean that China needs to accept and implement internationally agreed rules and institutions. It would also mean vice versa that Westerners accept the differences in the systems, the Chinese Way as well as the Chinese ‘market economy’, which is not meant to be the same like in Europe or North America.

关键词： innovation-driven China’s development intermediate assessment

Ontogeny of vocal rhythms in harbor seal pups: an exploratory study

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Current Zoology 2019年第1期65卷 107-120页

作者： Andrea RAViGNANi Christopher T. Kello koen de Reus Sonja A KoTz Simone Dalla BELLA Margarita Mendez-Arostegui Beatriz Rapado-Tamarit Ana Rubio-Garcia Bart de BoER Research Department Sealcentre Pieterburen Pieterburen The Netherlands Artificial Intelligenee Lab Vrije Universiteit Brussel Brussels Belgium Cognitive and Information Sciences University of California Merced CA USA Basic and Applied NeuroDynamics Lab Faculty of Psychology and Neuroscience Department of Neuropsychology & Psychopharmacology Maastricht University Maastricht The Netherlands Department of Neuropsychology Max-Planck Institute for Human Cognitive and Brain Sciences Leipzig Germany International Laboratory for Brain Music and Sound Research (BRAMS) Montreal QC Canada Department of Psychology University of Montreal Montreal QC Canada Department of Cognitive Psychology WSFiZ in Warsaw Warsaw Poland

Puppyhood is a very active social and vocal period in a harbor seal's life Ph oca vitulina. An important feature of vocalizations is their temporal and rhythmic structure, and understanding vocal timing and rhythms in harbor seals is critical to a cross-species hypothesis in evolutionary neuroscience that links vocal learning, rhythm perception, and synchronization. This study utilized analytical techniques that may best capture rhythmic structure in pup vocalizations with the goal of examining whether (1) harbor seal pups show rhythmic structure in their calls and (2) rhythms evolve over time. Calls of 3 wild-born seal pups were recorded daily over the course of 1-3 weeks;3 temporal features were analyzed using 3 complementary techniques. We identified temporal and rhythmic structure in pup calls across different time windows. The calls of harbor seal pups exhibit some degree of temporal and rhythmic organization, which evolves over puppyhood and resembles that of other species' in teractive comm un icati on. We suggest n ext steps for investigating call structure in harbor seal pups and propose comparative hypotheses to test in other pinniped species.

关键词： bioacoustics pinnipeds rhythm timing vocal development

Supplementing oat hulls to the diet of suckling piglets altered their intestinal tract and colonic microbiota development

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Animal Nutrition 2023年第1期12卷 284-296页

作者： Hubèrt M.J.van Hees koen Chiers Leo A.den Hartog Theo A.T.G.van Kempen Dominiek Maes Sam Millet Geert P.J.Janssens Department of Veterinary and Biosciences Ghent UniversityMerelbekeBelgium Trouw Nutrition Research and Development Amersfoortthe Netherlands Department of Pathology Ghent UniversityMerelbekeBelgium Animal Nutrition Wageningen University and ResearchWageningenthe Netherlands Department of Animal Science North Carolina State UniversityRaleighNCUSA Department of Reproduction Obstetrics and Herd HealthGhent UniversityMerelbekeBelgium ILVO(Flanders Research Institute for Agriculture Fisheries and Food)MelleBelgium

Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling *** hulls(OH)were selected as a model feedstuff,rich in cellulose,lignin,and insoluble dietary *** experimental supplemental diets were formulated:a finely ground,low fibre and nutrient dense diet served as control(CON).For the 2 high fibre diets,15%heat-treated starch in CON was exchanged with OH,either finely(OH-f)or coarsely ground(OH-c).Litters of 10 primi-and multiparous sows(mean litter size 14.6±0.84)were *** a litter,experimental diets were allotted to triplets of 4 *** approximately 12 d of age,piglets’individual feed intakes were recorded 2 times per day when separated from their dam for 70 *** could suckle with their dam for the remainder of the *** d 24 and 25,from the total pool of 120 piglets,seven healthy well-eating piglets per treatment were selected for post-mortem evaluation,resulting in 14 replicates per *** of OH-c and OH-f did not impede clinical health and production performance of *** full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate(P=0.083).Supplementing OH significantly increased ileal villus height and caecal dry matter concentration(P<0.05).For the colon,OH increased its length,contents weight,short-chain fatty acid concentration and reduced total bacterial count as well asγ-proteobacteria count and proportion(P<0.05).The OH-c treatment specifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and ***,OH-c reduced colonic crypt depth when compared to OH-f(P=0.018).In conclusion,supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial *** effects were largely independent from the particle size of the OH.

关键词： Oat hull Insoluble fibre Gastrointestinal development Suckling piglet