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Searching novel complex solid solution electrocatalysts in unconventional element combinations

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Nano Research 2022年第6期15卷 4780-4784页

作者： Olga A.Krysiak simon Schumacher Alan Savan Wolfgang Schuhmann Alfred Ludwig Corina Andronescu Analytical Chemistry-Center for Electrochemical Sciences(CES) Faculty of Chemistry and BiochemistryRuhr University BochumUniversitätsstr.150D-44780 BochumGermany Chemical Technology Ⅲ Faculty of ChemistryCarl-Benz-Straße 199D-47057 DuisburgGermany CENIdE-Center for Nanointegration University duisburg Essen Carl-Benz-Straße 199D-47057 DuisburgGermany Chair for Materials discovery and Interfaces Institute for MaterialsFaculty of Mechanical EngineeringRuhr University BochumUniversitätsstr.150D-44780 BochumGermany ZGH Ruhr University BochumUniversitätsstr.150D-44780 BochumGermany

despite outstanding accomplishments in catalyst discovery,finding new,more efficient,environmentally neutral,and noble metalfree catalysts remains challenging and ***,complex solid solutions consisting of at least five different elements and often named as high-entropy alloys have emerged as a new class of electrocatalysts for a variety of *** multicomponent combinations of elements facilitate tuning of active sites and catalytic *** optimal catalyst composition remains difficult,making testing of a very high number of them *** present the high-throughput screening of the electrochemical activity of thin film material libraries prepared by combinatorial co-sputtering of metals which are commonly used in catalysis(Pd,Cu,Ni)combined with metals which are not commonly used in catalysis(Ti,Hf,Zr).Introducing unusual elements in the search space allows discovery of catalytic activity for hitherto unknown *** libraries with very similar composition spreads can show different activities *** trends for different *** order to address the inherent challenge of the huge combinatorial material space and the inability to predict active electrocatalyst compositions,we developed a high-throughput process based on co-sputtered material libraries,and performed high-throughput characterization using energy dispersive X-ray spectroscopy(EdS),scanning transmission electron microscopy(SEM),X-ray diffraction(XRd)and conductivity measurements followed by electrochemical screening by means of a scanning droplet *** results show surprising material compositions with increased activity for the oxygen reduction reaction and the hydrogen evolution *** data are important input data for future data-driven materials prediction.

关键词： high-entropy alloys electrocatalysis high-throughput screening thin films hydrogen evolution reaction oxygen reduction reaction

Advances in the engineering of the outer blood-retina barrier:From in-vitro modelling to cellular therapy

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Bioactive Materials 2024年第1期31卷 151-177页

作者： Chloé dujardin Walter Habeler Christelle Monville didier Letourneur Teresa simon-Yarza UniversitéParis Cité UniversitéSorbonne Paris NordLaboratory for Vascular Translational Science(LVTS)INSERM-U114875018 ParisFrance INSERM U861 I-StemAFMInstitute for Stem Cell Therapy and Exploration of Monogenic Diseases91100Corbeil-EssonnesFrance U861 I-StemAFMUniversitéParis-SaclayUniversitéD’Evry91100Corbeil-EssonnesFrance CECS Centre D’étude des Cellules Souches91100Corbeil-EssonnesFrance

The outer blood-retina barrier(oBRB),crucial for the survival and the proper functioning of the overlying retinal layers,is disrupted in numerous diseases affecting the retina,leading to the loss of the photoreceptors and ultimately of *** study the oBRB and/or its degeneration,many in vitro oBRB models have been developed,notably to investigate potential therapeutic strategies against retinal ***,to this day,most of these pathologies are untreatable,especially once the first signs of degeneration are *** cure those patients,a current strategy is to cultivate in vitro a mature oBRB epithelium on a custom membrane that is further implanted to replace the damaged native *** a description of the oBRB and the related diseases,this review presents an overview of the oBRB models,from the simplest to the most ***,we propose a discussion over the used cell types,for their relevance to study or treat the *** designed for in vitro applications are then examined,by paying particular attention to the design evolution in the last years,the development of pathological models and the benefits of co-culture models,including both the retinal pigment epithelium and the ***,this review focuses on the models developed for in vivo implantation,with special emphasis on the choice of the material,its processing and its characterization,before discussing the reported pre-clinical and clinical trials.

关键词： Outer-blood retina barrier Tissue engineering and cellular therapy In-vitro disease modelling 3d complex models

Views Towards Play-based Learning and Its developmental and Academic Benefits:Perspectives of Pre-primary School Teachers,Principals and Curriculum designers in Asmara,Eritrea

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Views Towards Play-based Learning and Its Developmental and ...

作者： Tekli simon Haile 华中师范大学

学位级别：硕士

研究概要尽管研究一再表明,游戏是儿童全面发展和学习的一个重要方面,但将游戏融入儿童的学习,特别是在课堂上采用游戏,一直是一个有争议的问题。争议的产生是因为不同类型的基于游戏的学习（PBL）所带来的不同好处。文献较为关注两种... 详细信息

研究概要尽管研究一再表明,游戏是儿童全面发展和学习的一个重要方面,但将游戏融入儿童的学习,特别是在课堂上采用游戏,一直是一个有争议的问题。争议的产生是因为不同类型的基于游戏的学习（PBL）所带来的不同好处。文献较为关注两种类型的基于游戏的学习（PBL）:自由游戏和引导游戏。在自由游戏中,儿童有自主选择游戏性活动的权利,也可以决定活动的方向。而引导性游戏是指成人通过构建或引导PBL活动来完成特定的学习目标。两种教学方法各有利弊,但教师使用哪种方法取决于教师对PBL的看法,以及他们在尝试实施PBL时所面临的挑战,以及期望从PBL中获得的发展和学习益处。厄立特里亚有三类学龄前学校:公立、私立和教会学校。尽管这三类学校都遵循教育部设计的相同课程大纲,但由于学校拥有不同的背景,以及教育者对游戏具有不同的理解和实践方式,这三种类型学校中的PBL可能存在差异。因此,有必要探讨教育工作者如何在厄立特里亚学前教育背景下理解和实施PBL,以解释理论与实践之间的差距。研究问题、目标及意义各种研究将发展益处与儿童导向的自由游戏环境联系起来,在这种环境中,教育者扮演着间接或被动的角色,例如观察或准备环境以鼓励自由游戏。另外,以游戏和学术学习为重点的研究也考察了以游戏为基础的活动如何影响学生在诸如识字和数学等科目的学习。这些研究者倾向于促进使用相互指导和教师指导的游戏活动来支持学术学习。在这种PBL中,教育者在游戏中扮演着积极的角色,如引导预先设计的游戏,与学生合作,以及干预儿童主导的游戏以融入学习目标。学前教育已成为厄立特里亚教育体系组成的一个重要部分,特别是在该国自1993年独立后。自从国家独立以来,为提高学前教育的质量做了很多工作。然而,目前还没有足够的研究在学前机构评估如何引用PBL或其有效性。教育者如何概念化、看待和融入PBL也是一个尚未探讨的问题。因此,本研究的出发点是了解教育工作者对PBL的观点,以及他们如何看待PBL的发展和学术效益。本研究的目的是首先了解教育工作者,包括教师、校长和课程设计者,是如何概念化和看待PBL的。研究还探讨了教师如何在学习中实际融入游戏,以及在学习过程中面临的挑战。最后,本研究还探讨了教师从PBL中获得的发展和学术利益的期望。为了达到这一目的,本研究提出了以下四个研究问题。1.厄立特里亚学龄前教育工作者（教师、校长和课程设计者）如何概念化和看待PBL?2.幼儿教师如何将游戏融入教学过程?学前教育课程如何引导学前教育将PBL融入课堂?3.厄立特里亚幼儿教师在尝试将PBL融入课堂时面临哪些挑战?4.通过PBL教学法进行教学,学前教育者希望获得哪些发展和学术利益?这项研究将首先通过厄立特里亚的视角,对现有的关于如何构思和整合以游戏为基础的学前教育的文献做出贡献。本研究的另一个重要意义在于,有助于厄立特里亚的幼儿教师更好地理解PBL及其整合。最后,本文将为厄立特里亚背景下未来对PBL的研究当基础。研究设计与方法研究采用质性研究设计,通过半结构式访谈法和文献分析法收集数据。从这两个来源收集的数据有助于更清楚地了解所研究的问题。样本的选取采用一种有目的的抽样技术,称为最大变异抽样,也称为非均匀抽样。研究参与者包括教育部幼儿保育和教育的教师、校长以及课程设计人员。本研究从三所不同类型的学前机构选取九位教师和六位校长。此外,两名来自幼儿保育和教育办公室的工作人员参加了本研究,他们在幼儿保育和教育课程设计中发挥积极作用。遵循主题分析法,即理论分析法或自上而下的主题分析法,对访谈数据进行分析。首先对访谈数据进行转录和翻译。然后,根据四个研究问题对参与者的回答进行编码,并将其分类。最后,这些范畴构成了本研究的主题。研究同时分析了四份文献:（1）《早期学习与发展标准文件》;（2）《学前教育大纲》;（3）《学前教师指南》;（4）《幼儿保育与教育四年战略计划》。根据研究问题,对文献进行了分析。最后,利用三角剖分方法对不同来源的数据进行合并,检验这些来源的见解。数据收集获得了幼儿保育和教育办公室的批准,参与研究的教师、学校校长和幼儿保育和教育工作人员均给予了书面知情同意书。受访者提供的所有信息都是保密的。在数据分析中,根据参与者工作的学校类型对他们进行编码,以便隐藏他们的身份。主要结果研究结果描述了两种不同的观点的参与者如何实施PBL在他们的学校。58.82%的受试者将PBL分为自由游戏和引导游戏两种,并认为这些游戏学习方法有不同的目的。然而,29.41%的参与者认为PBL只是一种自由的游戏,不认为游戏可以有效地作为一种工具来教授具有特定学术目标的课程,如数学、阅读和写作技能。在实际实施方面,研究发现52.93%的教育工作者处于儿童-成人参与连续统、自由游戏和直接教学的极端。只有35.29%的被试能有效地实施引导游戏。因此,研究发现参与者的

关键词：学前教育游戏化学习教学模式课程大纲

does laser surface texturing really have a negative impact on the fatigue lifetime of mechanical components?

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Friction 2021年第6期9卷 1766-1775页

作者： Chia-Jui HSU Andreas STRATMANN simon MEdINA Georg JACOBS Frank MÜCKLICH Carsten GACHOT Institute for Engineering design and Product development TU WienLehárgasse 6Campus GetreidemarktVienna 1060Austria Chair of Functional Materials Saarland UniversityCampus D3.3Saarbrücken 66123Germany AC2T Research GmbH Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria Institute for Machine Elements and Systems Engineering RWTH AachenSchinkelstraße 10Aachen 52062Germany

Laser surface texturing(LST)has been proven to improve the tribological performance of machine *** micro-scale patterns manufactured by LST may act as lubricant reservoirs,thus supplying oil when encountering insufficient ***,not many studies have investigated the use of LST in the boundary lubrication regime,likely due to concerns of higher contact stresses that can occur with the increasing surface *** study aims to examine the influence of LST on the fatigue lifetime of thrust rolling bearings under boundary lubrication.A series of periodic patterns were produced on the thrust rolling bearings,using two geometrically different designs,namely cross and dimple *** oil ISO VG 100 mixed with 0.05 wt%P of zinc dialkyldithiophosphate(ZddP)was *** bearings with cross patterns reduce the wear loss by two orders of *** patterns not only retain lubricant in the textured pockets but also enhance the formation of an anti-wear *** tribofilm generation may be improved by the higher contact stresses that occur when using the textured ***,in contrast to the negative concerns,the ball bearings with cross patterns were instead found to increase the fatigue life by a factor of three.

关键词： thrust rolling bearing laser surface texturing direct laser interference patterning zinc dialkyldithiophosphate(ZddP) tribofilm

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Challenges of liver cancer:Future emerging tools in imaging and urinary biomarkers

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World Journal of Hepatology 2015年第26期7卷 2664-2675页

作者： Francesca M Trovato Joshua M Tognarelli Mary ME Crossey daniela Catalano simon d Taylor-Robinson Guglielmo M Trovato dipartimento di Medicina Clinica e Sperimentale Scuola di Medicina Università di Catania department of Medicine Imperial College London St Mary’s Campus

Chronic liver disease has become a global health problem as a result of the increasing incidence of viral hepatitis, obesity and alcohol misuse. Over the past three decades, in the United Kingdom alone, deaths from chronic liver disease have increased both in men and in women. Currently, 2.5% of deaths worldwide are attributed to liver disease and projected figures suggest a doubling in hospitalisation and associated mortality by 2020. Chronic liver diseases vary for clinical manifestations and natural history, with some individuals having relatively indolent disease and others with a rapidly progressive course. About 30% of patients affected by hepatitis C has a progressive disease and develop cirrhosis over a 20 years period from the infection, usually 5-10 years after initial medical presentation. The aim of the current therapeutic strategies is preventing the progression from hepatitis to fibrosis and subsequently, cirrhosis. Hepatic steatosis is a risk factor for chronic liver disease and is affecting about the half of patients who abuse alcohol. Moreover non-alcoholic fatty liver disease is part of the metabolic syndrome, associated with obesity, hypertension, type Ⅱ diabetes mellitus and dyslipidaemia, and a subgroup of patients develops non-alcoholic steatohepatitis and fibrosis with subsequent cirrhosis. The strengths and pitfalls of liver biopsy are discussed and a variety of new techniques to assess liver damage from transient elastography to experimental techniques, such as in vitro urinary nuclear magnetic resonance spectroscopy. Some of the techniques and tests described are already suitable for more widespread clinical application, as is the case with ultrasound-based liver diagnostics, but others, such as urinary metabonomics, requires a period of critical evaluation or development to take them from the research arena to clinical practice.

关键词： Virus hepatitis Liver cancer Ultrasound Fibrosis U

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稳定性氢同位素分析在牛肉产地溯源中的应用

分析化学 2009年第9期37卷 1333-1336页

作者：郭波莉魏益民 Kelly d.simon 潘家荣魏帅中国农业科学院农产品加工研究所/农业部农产品加工与质量控制重点实验室 Institute of Food Research Norwich

探讨了利用高温热解炉和同位素比率质谱仪(IRMS)联用测定肉品中稳定性氢同位素比率的方法,并利用此方法测定了我国不同地域来源脱脂牛肉、牛尾毛中氢同位素比率。分析了牛组织中氢同位素组成与地域经度、纬度及海拔高度变化的关系,以及... 详细信息

探讨了利用高温热解炉和同位素比率质谱仪(IRMS)联用测定肉品中稳定性氢同位素比率的方法,并利用此方法测定了我国不同地域来源脱脂牛肉、牛尾毛中氢同位素比率。分析了牛组织中氢同位素组成与地域经度、纬度及海拔高度变化的关系,以及稳定性氢同位素用于牛肉产地溯源的可行性。结果表明,不同地域来源牛组织中δ2H值的差异显著,其与当地饮水中氢同位素组成密切相关,而且有随着地理纬度增加而减小的趋势;牛尾毛与牛肉中δ2H值的相关性显著。稳定性氢同位素是用于牛肉产地溯源的一项很有潜力的指标,且牛肉和牛尾毛中的氢同位素组成均可反映牛来源地的信息。

关键词：牛肉产地溯源稳定性氢同位素

Non-invasive means of measuring hepatic fat content

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World Journal of Gastroenterology 2008年第22期14卷 3476-3483页

作者： Sanjeev R Mehta E Louise Thomas Jimmy d Bell desmond G Johnston simon d Taylor-Robinson division of Medicine Imperial College London St Mary's Campus Praed Street London W2 1NY United Kingdom Imaging Sciences depart-ment Division of Clinical Sciences Imperial College London Hammersmith Campus Du Cane Road London W12 OHS United Kingdom

Hepatic steatosis affects 20% to 30% of the general adult population in the western world. Currently, the technique of choice for determining hepatic fat deposition and the stage of fibrosis is liver biopsy. However, it is an invasive procedure and its use is limited, particularly in children. It may also be subject to sampling error. Non-invasive techniques such as ultrasound, computerised tomography (CT), magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (1H MRS) can detect hepatic steatosis, but currently cannot distinguish between simple steatosis and steatohepatitis, or stage the degree of fibrosis accurately. Ultrasound is widely used to detect hepatic steatosis, but its sensitivity is reduced in the morbidly obese and also in those with small amounts of fatty infiltration. It has been used to grade hepatic fat content, but this is subjective. CT can detect hepatic steatosis, but exposes subjects to ionising radiation, thus limiting its use in longitudinal studies and in children. Recently, magnetic resonance (MR) techniques using chemical shift imaging have provided a quantitative assessment of the degree of hepatic fatty infiltration, which correlates well with liver biopsy results in the same patients. Similarly, in vivo 1H MRS is a fast, safe, non-invasive method forthe quantification of intrahepatocellular lipid (IHCL) levels. Both techniques will be useful tools in future longitudinal clinical studies, either in examining the natural history of conditions causing hepatic steatosis (e.g. non-alcoholic fatty liver disease), or in testing new treatments for these conditions.

关键词： Adipose tissue Ectopic fat Hepatic fat Insulin resistance Ultrasound Computerised tomography Magnetic resonance imaging Magnetic resonance spectroscopy

Numerical optimisation and experimental validation of divided rail freight brake disc crown

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Journal of Modern Transportation 2019年第1期27卷 1-10页

作者： Uro? Grivc david derzi? simon Muhi? KOVIS d.o.o. Faculty of Mechanical Engineering University of Novo mesto SIMUTEH

In this study, numerical optimisation and experimental validation of a divided rail freight brake disc crown made of grey cast iron EN-GJL-250 is *** analysed brake disc is used in rail freight wagons and possesses a load capacity of 22.5 tons per axle. Two of the divided rail freight brake discs are mounted on each *** the aid of numerical analysis, the thermal dissipation properties of the brake disc were optimised and ventilation losses were reduced, and the numerical results were compared with experimental results. A one-way fluid–structure interaction analysis was performed. A computational fluid dynamic model of a divided rail freight brake disc, used to predict air flow properties and heat convection, was incorporated into a finite element model of the disc and used to evaluate the temperature of the disc. A numerical parametrical optimisation of cooling ribs of the brake disc was also performed, and novel optimised cooling ribs were developed. A transient thermal numerical analysis of the brake disc was validated using temperature measurements obtained during a braking test on a test bench. The ventilation losses of the brake disc were measured on a test bench specifically designed for the task, and the losses were compared to the simulation results. The experimentally obtained ventilation losses and temperature measurements compared favourably with the simulation results, confirming that this type of simulation process may be confidently applied in the future. Through systematic optimisation of the divided rail freight brake disc, ventilation losses were reduced by 37% and the mass was reduced by 21%, resulting in better thermal performance that will bring with it substantial energy savings.

关键词： divided rail freight brake disc Computational fluid dynamics Finite element method Computer-aided engineering One-way fluid-structure interaction

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Ultrafast Synthesis of Calcium Vanadate for Superior Aqueous Calcium-Ion Battery

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Research 2019年第1期2019卷 85-95页

作者： Liyuan Liu Yih-Chyng Wu Patrick Rozier Pierre-Louis Taberna Patrice simon CIRIMAT UMR CNRS 5085UniversitéPaul Sabatier Toulouse III118 route de Narbonne31062 ToulouseFrance RS2E Réseau Français sur le Stockage Electrochimique de l’EnergieFR CNRS 345980039 Amiens CEDEXFrance

Recently,multivalent aqueous calcium-ion batteries(CIBs)have attracted considerable attention as a possible alternative to Li-ion ***,traditional Ca-ion storage materials show either limited rate capabilities and poor cycle life or insufficient specific ***,we tackle these limitations by exploring materials having a large interlayer distance to achieve decent specific capacities and one-dimensional architecture with adequate Ca-ion passages that enable rapid reversible(de)intercalation *** this work,we report the high-yield,rapid,and low-cost synthesis of 1d metal oxides MV_(3)O_(8)(M=Li,K),CaV_(2)O_(6),and CaV_(6)O_(16)·7H_(2)O(CVO)via a molten salt ***,using 1d CVO as electrode materials,we show high capacity 205 mA h g^(-1),long cycle life(>97%capacity retention after 200 cycles at 3.0 C),and high-rate performance(117 mA h g^(-1) at 12 C)for Ca-ion(de)*** work represents a step forward for the development of the molten salt method to synthesize nanomaterials and to help pave the way for the future growth of Ca-ion batteries.

关键词： method. retention reversible