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Redox flow batteries-Concepts and chemistries for cost-effective energy storage

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Frontiers in Energy 2018年第2期12卷 198-224页

作者： Matthaa verena HOLLAND-CUNZ Faye CORDING Jochen FRIEDL Ulrich STIMMING Chemistry-School of Natural and Environmental Sciences Newcastle University Newcastle upon Tyne NE1 7RU United Kingdom

Electrochemical energy storage is one of the few options to store the energy from intermittent renewable energy sources like wind and solar. Redox flow batteries （RFBs） are such an energy storage system, which has favorable features over other battery technologies, e.g. solid state batteries, due to their inherent safety and the independent scaling of energy and power content. However, because of their low energy-density, low powerdensity, and the cost of components such as redox species and membranes, commercialised RFB systems like the all- vanadium chemistry cannot make full use of the inherent advantages over other systems. In principle, there are three pathways to improve RFBs and to make them viable for large scale application： First, to employ electrolytes with higher energy density. This goal can be achieved by increasing the concentration of redox species, employing redox species that store more than one electron or by increasing the cell voltage. Second, to enhance the power output of the battery cells by using high kinetic redox species, increasing the cell voltage, implementing novel cell designs or membranes with lower resistance. The first two means reduce the electrode surface area needed to supply a certain power output, thereby bringing down costs for expensive components such as membranes. Third, to reduce the costs of single or multiple components such as redox species or membranes. To achieve these objectives it is necessary to develop new battery chemistries and cell configurations. In this review, a comparison of promising cell chemistries is focused on, be they all-liquid, slurries or hybrids combining liquid, gas and solid phases. The aim is to elucidate which redox-system is most favorable in terms of energy-density, power-density and capital cost. Besides, the choice of solvent and the selection of an inorganic or organic redox couples with the entailing consequences are discussed.

关键词： electrochemical energy storage redox flow battery vanadium

超越原子可视化—利用扫描透射电子显微镜表征双原子单团簇催化剂

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Science China Materials 2023年第7期66卷 2733-2740页

作者：李铖陈俊池汪兴坤黄明华 Wolfgang theis 李隽谷猛 Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China School of Physics and Astronomy University of BirminghamBirminghamB152TTUK Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and TechnologyShenzhen 518055China School of Materials Science and Engineering Ocean University of ChinaQingdao 266100China Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua UniversityBeijing 100084China

本研究利用扫描透射电子显微镜(STEM)表征了碳掺杂氮负载的FeFe和CoFe双原子单团簇催化剂.同时本工作开发了一个STEM图像处理程序,以精准识别原子的位置并得到可能的原子对中原子之间的投影距离.大数据分析结果显示CoFe和FeFe原子对的... 详细信息

本研究利用扫描透射电子显微镜(STEM)表征了碳掺杂氮负载的FeFe和CoFe双原子单团簇催化剂.同时本工作开发了一个STEM图像处理程序,以精准识别原子的位置并得到可能的原子对中原子之间的投影距离.大数据分析结果显示CoFe和FeFe原子对的距离均呈现三峰分布,对应于模拟得到的多种稳定的原子结构.我们的工作为通过STEM图像的大数据统计和相关理论模拟直接揭示双原子单团簇催化剂中双原子位点的可能原子构型提供了一条途径.

关键词： single-cluster catalysts aberration-corrected HAADF-STEM image processing big data statistics DFT simulation

Targeted expression of human FSH receptor Asp567Gly mutant mRNA in testis of transgenic mice: role of humanFSH receptor promoter

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Asian Journal of Andrology 2003年第4期5卷 267-275页

作者： verena Nordhoff Jrg Gromoll Luca Foppiani C.Marc Luetjens Stefan Schlatt Elena Kostova Ilpo Huhtaniemi Eberhard Nieschlag Manuela Simoni Institute of Reproductive Medicine University of Miinster D-48149 Munster Germany Department of Physiology University of Turku Kiinamyllynkatu 10 FIN-20520 Turku Finland

Aim: To specifically express the Asp567Gly human follicle-stimulating hormone receptor (FSHR) under the control of its promoter to evaluate the phenotypic consequences in the presence of normal pituitary function. Methods: We produced transgenic mice overexpressing the Asp567Gly human FSHR under the control of a 1.5kb 5' flanking region fragment of its promoter. Results: Mice were phenotypically normal and fertile. In males, mRNA could be detected in the testis and the brain, indicating that the 1.5kb promoter fragment drives expression not only in the gonads. The testis weight/body weight ratio and the testosterone levels in transgenic and non-transgenic litter mates were similar. By in situ hybridisation we found that the transgenic FSHR was highly expressed in Sertoli cells, spermatocytes and round spermatids. However, a radioligand receptor assay failed to show a significant difference in total FSHR binding sites in testis homogenates of transgenic and wild type animals, suggesting that the transgenic FSHR is probably not translated into functional receptor protein. Conclusion: A 1.5kb 5 '-region of the human FSHR drives mRNA expression of the transgene in the testis but leads to ectopic expression in germ cells and in the brain. No phenotypic consequences could be documented due to the lack of protein expression.

关键词： transgenic mouse follicle-stimulating hormone receptor promoter activating mutation Sertoli cells

Symbiotic Cultural Heritage Tourism

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China Today 2015年第12期64卷 29-32页

作者： FU ZHIBIN verena MENZEL 不详

TILL recently,China's coastal southeastern provinces have reaped the greatest benefits from the reform and opening-up policy since it came into effect in *** now the inland and western regions are getting a *** Belt and Road Initiative,proposed in 2013,promises fresh development opportunities for China's central and western regions,especially in light of their abundant cultural and tourismresources.

关键词： Symbiotic Cultural Heritage Tourism

Sound Quality of Turn Indicator Sounds-Use of aMultidimensional Approach in the Automotive ProductDevelopment

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Journal of Traffic and Transportation Engineering 2015年第3期3卷 158-165页

作者： verena Wagner Konrad Wolfgang Kallus Department of Psychology Work. Organizational and Environmental Psychology University of Graz Graz 8010 Austria

Vehicle sounds are important factors of customer satisfaction and have a decisive influence on the product automobile andits quality impression. It becomes more and more important to connect customer requirements and technical specifications to developa vehicle sound with high quality. The turn indicator sound can be described as one sound, which gives the customer an importantfeedback of correct function performance and can be seen as one of the sounds, which play a role in the customer＇s perception ofvehicle quality. In a laboratory experimental study, the question was investigated, how a turn indicator sound must be designed to beperceived as pleasant and high-quality. A multidimensional approach was chosen to combine subjective customer assessments,objective psychophysiological responses of the study participants and physical parameters of the sounds. In total, 15 different tumindicator sounds were assessed by 48 subjects. The study shows how the connection of subjective and objective parameters cansupport product development. The multi-dimensional approach helps to derive recommendations for action to improve the soundquality of the product automobile. Also, the study shows a possibility to involve the human factor in a highly technical environment.

关键词： Vehicle sound quality, multi-dimensional approach, experimental study, customer requirements, technicalspecifications.

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

Treatment of osteoarthritis by implantation of Mg- and WE43-cylinders - A preclinical study on bone and cartilage changes and their influence on pain sensation in rabbits

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Bioactive Materials 2024年第10期40卷 366-377页

作者： Nina Angrisani Christin von der Ahe Regine Willumeit-R¨omer Henning Windhagen verena Scheper Michael Schwarze Bj¨orn Wiese Heike Helmholz Janin Reifenrath Hannover Medical School Clinic for Orthopaedic SurgeryLower Saxony Centre for Biomedical EngineeringImplant Research and Development(NIFE)HannoverLower SaxonyGermany Helmholtz-Zentrum Hereon Institute of Metallic BiomaterialsGeesthachtGermany Hannover Medical School Department of OtolaryngologyLower Saxony Centre for Biomedical EngineeringImplant Research and Development(NIFE)HannoverLower SaxonyGermany Hannover Medical School Clinic for Orthopaedic SurgeryLaboratory for Biomechanics and BiomaterialsHannoverLower SaxonyGermany

With its main features of cartilage degeneration, subchondral bone sclerosis and osteophyte formation, osteoarthritisrepresents a multifactorial disease with no effective treatment options. As biomechanical shift in thetrabecular network may be a driver for further cartilage degeneration, bone enhancement could possibly delayOA progression. Magnesium is known to be osteoconductive and already showed positive effects in OA *** aimed to use magnesium cylinders to enhance subchondral bone quality, condition of cartilage and painsensation compared to sole drilling in vivo. After eight weeks of implantation in rabbits, significant increase insubchondral bone volume and trabecular thickness with constant bone mineral density was found indicatingfavored biomechanics. As representative for pain, a higher number of CD271+ vessels were present in controlsamples without magnesium. However, this result could not be confirmed by sensitive, objective lamenessevaluation using a pressure sensing mat and no positive effect could be shown on either cartilage degenerationevaluated by OARSI score nor the presence of regenerative cells in CD271-stained samples. The presented resultsshow a relevant impact of implanted magnesium on key structures in OA pain with missing clinical relevanceregarding pain. Further studies with shifted focus should examine additional structures as joint capsule orosteophytes.

关键词： Magnesium Subchondral bone In vivo Gait analysis μ-computed tomography CD271

Mountain Wood vs. Lowland Wood Harvesting Methods： An Ecological Case Study

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Journal of Civil Engineering and Architecture 2014年第1期8卷 89-99页

作者： Anton Kraler verena Krismer Georg Wieland Timber Engineering Unit--Institute for Structural Engineering and Materials Science University of lnnsbruck lnnsbruck 6020Austria

Are Austrian mountain wood harvesting techniques more ecological than techniques applied in the lowlands of southern Germany？ For this comparative study, the authors selected the area of Lower Bavaria for lowland wood, as a great deal of wood is imported from this region to western Austria. At first, the felling area is described for both regions, from forest site to sawmill. Thereby, the authors create mean values related to timber harvesting and transportation, which are applicable to the whole of western Austria and Lower Bavaria, southern Germany. Secondly, the eco-balance of mountain and lowland wood is established. It is based on the following impact categories： global warming potential, acidification potential, eutrophication potential, ozone depletion potential and non-renewable primary energy. The environmental impact is more expressive if the results are applied to a specific construction part （i.e., glued laminated timber-ceiling）. Our research study showed the eco-balance of western Austrian mountain wood is more favourable than the environmental impact of harvesting lowland wood in southern Germany.

关键词： Mountain wood lowland wood harvesting techniques eco-balance global warming potential.

Lactobacilli,bifi dobacteria and *** nissle induce pro-and anti-inflammatory cytokines in peripheral blood mononuclear cells

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World Journal of Gastroenterology 2006年第37期12卷 5978-5986页

作者： Ulf Helwig Karen M Lammers Fernando Rizzello Patricia Brigidi verena Rohleder Elisabetta Caramelli Paolo Giochetti Juergen Schrezenmeir Ulrich R Foelsch Stefan Schreiber Massimo Campieri University Hospital Schleswig-Holstein Campus Kiel 1~(st) Medical Department Schittenhelmstr.12 24105 Kiel Germany University of Bologna Department of Internal Medicine and Gastroenterology Policlinico S. Orsola Via Massarenti 9 40138 Bologna Italy University of Bologna Department of Internal Medicine and Gastroenterology Policlinico S. Orsola Via Massarenti 9 40138 Bologna Italy University of Bologna Institute for Microbiology Via Bellmeloro 9 40138 Bologna Italy University Hospital Schleswig-Holstein Campus Kiel 1~(st) Medical Department Schittenhelmstr.12 24105 Kiel Germany University of Bologna Histology and General Embryology and Pharmaceutical Science Via Bellmeloro 9 40138 Bologna Italy Federal Research Center for Nutrition and Food Location Kiel Institute for Physiology and Bioche- mistry of Nurtition Hermann-Weigmann-Str.1 24103 Kiel Germany

AIM： To investigate whether the stimulation of peripheral blood mononuclear cells （PBMNC） with the cell debris and cell extraction of different probiotic strains is similar or species specific. METHODS： Three strains of bifidobacteria, 4 strains of lactobacilli, and E. coli nissle were sonicated and centrifuged in order to divide them into cell extract and cell debris. PBMNC were separated by density gradient and incubated for 36 h with either the cell debris or the cell extract of single strains of probiotic bacteria in doses from 10^2 to 10^8 CFU/mL. Cell supernatants were taken and interleukin （IL）-10, IL-1β, and tumor necosis factor （TNF）-α were determined by ELISA. RESULTS： Depending on the species super-family, the strains had different stimulation patterns. Except for both L. casei strains, the cell extract of bitTdobacteria and/actobacilli had less stimulating capacity than cell debris, whereas the cell extract of E. coli nissle had similar stimulating properties to that of the cell debris of the strain and significantly more stimulating capacity than that of bifidobacteria and lactobacilli. The cell debris of bifidobacteria stimulated more cytokine release than the cell debris of lactobacilli. The cell debris of lactobacilli did not have a stimulating capacity when lower concentrations were used. Neither cell extraction nor cell debris had an inhibitory effect on the production of the tested cytokines by stimulated PBMNC. CONCLUSION： The incubation of probiotic strains, which have been used in clinical trials for inflammatory diseases, with immunocompetent cells leads to different species specific reactions. High IL-10 response to cell debris of bifidobacteria and E. coli nissle can be found. This corresponds to positive effects of bihdobacteria and E. coli nissle in clinical trials for inflammatory bowel disease compared to negative outcomes obtained with lactobacilli.

关键词： Lactobacilli Bifidobacteria Probiotics Interleukin-l0 Tumor necrosis factor-α Interleukin-1β Peripheral blood mononuclear cells