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Frontiers of Mechanical Engineering 2023年第4期18卷 183-193页

作者： Alexander SCHMIDT Felix JENSCH sebastian HÄRTEL Chair of Hybrid Manufacturing Brandenburg University of TechnologyCottbus 03046Germany

Many processes may be used for manufacturing functionally graded *** them,additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one *** adjusting the powder composition of the starting material layer by layer,a macroscopic and step-like gradient can be *** further improve the step-like gradient,an enhancement of the in-situ mixing degree,which is limited according to the state of the art,is *** this paper,a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting(LR)is *** effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion *** cross-sectional selective electron microscopic analyses were carried *** applying LR,the mixing degree was enhanced,and the reaction zone thickness between the materials was ***,an additional copper and iron-based phase was formed in the interface,resulting in a smoother gradient of the chemical composition than the case without *** Marangoni convection flow and thermal diffusion are the driving forces for the observed effect.

关键词： multi-material additive manufacturing(MMAM) functionally graded materials(FGMs) laser powder bed fusion(L-PBF) laser remelting(LR) pure copper

Design and Construction Challenges for a Hybrid Air and Thermal Energy Storage System Built in the Post-Mining Shaft

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Journal of Thermal Science 2022年第5期31卷 1302-1317页

作者： WANICZEK sebastian OCHMANN Jakub BARTELA Lukasz RULIK sebastian LUTYNSKI Marcin BRZUSZKIEWICZ Michal KOLODZIEJ Konrad SMOLNIK Grzegorz JURCZYK Michal LIPKA Marian Energoprojekt-Katowice SA Katowice40-159Poland Department of Power Engineering and Turbomachinery Silesian University of TechnologyGliwice44-100Poland Department of Mining Silesian University of TechnologyGliwice44-100Poland Department of Geomechanics and Underground Construction Silesian University of TechnologyGliwice44-100Poland

Compressed Air Energy Storage(CAES)is one of the methods that can solve the problems with intermittency and unpredictability of renewable energy sources.A side effect of air compression is a fact that a large amount of heat is generated which is usually *** the development of CAES systems,the main challenge,apart from finding suitable places for storing compressed air,is to store this heat of compression process so that it can be used for heating the air directed to the expander at the discharging *** paper presents the concept of a hybrid compressed air and thermal energy storage(HCATES)system,which may be a beneficial solution in the context of the two mentioned *** novel concept assumes placing the thermal energy storage(TES)system based on the use of solid storage material in the volume of the post-mining shaft forms a sealed air pressure *** of proposed systems within heavily industrialized agglomerations is a potential pathway for the revitalization of post-mine *** potential of energy capacity of such systems for the Upper Silesian region could exceed the value of 10 *** the paper,the main construction challenges related to this concept are *** issues related to the possibility of storing air under high pressure in the shaft from the view of the rock mass strength are *** overall concept of the TES system installation solution in the shaft barrel is *** basic problems related to heat storage in the cylindrical TES system with a non-standard structure of high slenderness are also *** numerical calculations were based on the results of experiments performed on a laboratory stand,the geometry of which is to reflect the construction of a TES tank in a post-mining *** article presents the results of numerical analysis showing the basic aspects related to difficulties that may occur at the construction stage and during the operation of the proposed HCATES *** paper

关键词： energy compressed air energy storage thermal energy storage post-mine areas revitalization structure analysis

Molecular dynamics simulation of the Stribeck curve: Boundary lubrication, mixed lubrication, and hydrodynamic lubrication on the atomistic level

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摩擦:英文版 2023年第12期11卷 2342-2366页

作者： Simon STEPHAN sebastian SCHMITT Hans HASSE Herbert M.URBASSEK Laboratory of Engineering Thermodynamics(LTD) Department of Mechanical and Process EngieeringTU KaiserslauternRheinland-Pfalz 67663Germany Physics Department and Research Center(OPTIMAS) TU KaiserslauternRheinland-Pfalz 67663Germany

Lubricated contact processes are studied using classical molecular dynamics simulations for determining the entire range of the Stribeck ***,the lateral movement of two solid bodies at different gap height are *** each simulation,a rigid asperity is moved at constant height above a flat iron surface in a lubricating *** methane and decane are considered as *** three main lubrication regimes of the Stribeck curve and their transition regions are covered by the study:Boundary lubrication(significant elastic and plastic deformation of the substrate),mixed lubrication(adsorbed fluid layer dominates the process),and hydrodynamic lubrication(shear flow is set up between the surface and the asperity).We find the formation of a tribofilm in which lubricant molecules are immersed into the metal surface—not only in the case of scratching,but also for boundary lubrication and mixed *** formation of a tribofilm is found to have important consequences for the contact ***,the two fluids are found to show distinctly different behavior in the three lubrication regimes:For hydrodynamic lubrication(large gap height),decane yields a better tribological performance;for boundary lubrication(small gap height),decane shows a larger friction coefficient than methane,which is due to the different mechanisms observed for the formation of the tribofilm;the mixed lubrication regime can be considered as a transition regime between the two other ***,it is found that the nature of the tribofilm depends on the lubricant:While methane particles substitute substrate atoms sustaining mostly the crystalline structure,the decane molecules distort the substrate surface and an amorphous tribofilm is formed.

关键词： boundary lubrication mixed lubrication hydrodynamic lubrication molecular dynamics simulation tribofilm

Why are COVID-19 travel bubbles a tightrope walk?An investigation based on the Trans-Tasmanian case

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Communications in Transportation Research 2023年第1期3卷 37-43页

作者： Xiaoqian Sun sebastian Wandelt Anming Zhang National Key Laboratory of CNS/ATM School of Electronic and Information EngineeringBeihang UniversityBeijing100191China Sauder School of Business University of British ColumbiaVancouverBCCanada

The COVID-19 pandemic has hit the transportation sector hard;particularly air transportation,as a major mode of long-distance transportation,has been affected *** the dawn of COVID-19,politicians and policy makers have discussed the idea of introducing travel bubbles between countries(or counties),to allow for a continued exchange of people and *** eponymous Trans-Tasmanian travel bubble is a major example,involving quarantine-free travel between Australia and New *** both countries have tried to form a travel bubble various times,recurring setbacks and difficulties were *** October 2021,this ambitious project presumably has come to an end,with both countries announcing the essential capitulation of their COVIDZero strategies and a planned opening towards broader international *** this study,we perform a close investigation of the history behind the Trans-Tasmanian travel bubble as an on-off relationship,identifying a set of drivers for the serious problems involving a sustainable setup and *** develop a framework which represents important factors for successful travel bubbles and believe that the satisfaction of all factors at once is extremely *** results and insights are not specific to the Trans-Tasmanian case only,although it is taken as a running example,but can be generalized to various scales and *** hope that our study contributes to the literature by improving our understanding of the highly buzzed travel bubble concept,while providing empirical evidence for the troubles that inherently make such bubbles a tightrope walk.

关键词： COVID-19 Travel bubble Australia New Zealand

ESCRT machinery:role of membrane repair mechanisms in escaping cell death

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Signal Transduction and Targeted Therapy 2022年第8期7卷 2655-2657页

作者： Lisa Gregor Sophia Stock sebastian Kobold Division of Clinical Pharmacology Department of Medicine IVUniversity HospitalLudwig Maximilian University(LMU)of MunichLindwurmstrasse 2a80337 MunichGermany Department of MedicineⅢ University HospitalLudwig Maximilian University(LMU)of MunichMarchioninistrasse 1581377 MunichGermany German Cancer Consortium(DKTK) Partner Site MunichPettenkoferstrasse 8a80336 MunichGermany Einheit für Klinische Pharmakologie(EKLiP) Helmholtz Zentrum MünchenGerman Research Center for Environmental Health(HMGU)Ingolstädter Landstrasse 185764 NeuherbergGermany

A recent research article published in Science by Ritter et *** that endosomal sorting complexes required for transport(ESCRT)proteins mediate repair of lesions in the cell membrane caused by the pore-forming toxin perforin at sites of cytotoxic T cell engagement.1 Subsequent entry of granzymes and initiation of apoptosis of cancer cells is thus limited,leading to reduced sensitivity against T cell‑mediated cytotoxicity.1 Along these lines,this could constitute a new critical resistance mechanism for T cellbased treatment approaches.

关键词： al. cytotoxicity death

Comparison of EUV Photomask Metrology Between CD-AFM and TEM

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Nanomanufacturing and Metrology 2022年第2期5卷 91-100页

作者： Gaoliang Dai Kai Hahm Lipfert sebastian Markus Heidelmann Physikalisch-Technische Bundesanstalt 38116BraunschweigGermany Advanced Mask Technology Center GmbH&Co.KG 01109DresdenGermany ICAN Universität Duisburg-Essen47057DuisburgGermany

Accurate metrology of extreme ultraviolet (EUV) photomask is a crucial task. In this paper, two different methods for reference EUV photomask metrology are compared. One is the critical dimension atomic force microscopy (CD-AFM). In the measurements, the contribution of its AFM tip geometry is usually the dominant error source, as measured AFM images are the dilated results of measured structures by the AFM tip geometry. To solve this problem, a bottom-up approach has been applied in calibrating the (effective) AFM tip geometry where the result is traceably calibrated to the lattice constant of silicon crystals. The other is transmission electron microscopy (TEM). For achieving measurement traceability, structure features are measured in pairs in TEM images;thus the distance between the structure pair calibrated by a metrological AFM in prior can be applied to determine the magnification of the TEM image. In this study, selected photomask structures are calibrated by the CD-AFM, and then sample prepared and measured by high-resolution TEM nearly at the same location. The results are then compared. Of six feature groups compared, the results agree well within the measurement uncertainty, indicating excellent performance of the developed methodology. This research supports the development of a photomask standard, which is applied as a “reference ruler” with improved low measurement uncertainty in photomask fabs.

关键词： Extreme ultraviolet(EUV)photomask standard Traceable calibration Metrology Critical dimension(CD) Atomic force microscopy(AFM) Transmission electron microscopy(TEM) High precision Low measurement uncertainty

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用户体验和装配:以人为本

现代制造 2024年第2期 36-36页

作者： sebastian Human 不详

UX是英文“Positive User Experience良好的用户体验”一词的缩写,指的是企业员工,尤其是装配工使用装配工位器具时的“用户体验”。用户体验不仅提高了装配工的安装工作效率,也提高了装配工的生产能力。但用户体验的UX策略是如何支持... 详细信息

UX是英文“Positive User Experience良好的用户体验”一词的缩写,指的是企业员工,尤其是装配工使用装配工位器具时的“用户体验”。用户体验不仅提高了装配工的安装工作效率,也提高了装配工的生产能力。但用户体验的UX策略是如何支持装配工作流程优化的呢?它与安全有什么关系呢?

关键词：用户体验工位器具工作流程优化工作效率以人为本装配生产能力

Phosphorylated Salicylic Acid as Flame Retardant in Epoxy Resins and Composites

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Journal of Renewable Materials 2022年第7期10卷 1931-1950页

作者： Lara Greiner Philipp Kukla sebastian Eibl Manfred Döring Bundeswehr Research Institute for Materials Fuels and LubricantsErding85435Germany Fraunhofer Institute for Structural Durability and System Reliability LBF Darmstadt64289Germany Schill+Seilacher GmbH Böblingen71032Germany

A novel,versatile flame retardant substructure based on phosphorylated salicylic acid(SCP)is described and used in the synthesis of new flame retardants for HexFlowRTM6,a high-performance epoxy resin used in resin transfer molding processes as composite *** starting material salicylic acid can be obtained from natural *** as reactive phosphorus chloride is converted with a novolak,a novolak containing 9,10-dihydro-9-oxa-10-phospha-phenanthrene-10-oxide(DOPO)substituents or DOPO-hydroquinone to flame retardants with sufficient thermal stability and high char ***,these flame retardants are soluble in the resin as well as react into the epoxy *** determined thermal stability and glass transition temperatures of flame retarded neat resin samples as well as the interlaminar shear strength of corresponding carbon fiber reinforced composite materials showed the applicability of these flame *** resin samples and composites were tested for their flammability by UL94 and/or flame-retardant performance by cone *** tested flame retardants decrease the peak of heat release rate by up to 54%for neat resin samples.A combination of DOPO and SCP in one flame retardant shows synergistic effects in char formation and the mode of action adapts to neat resin or fiber-reinforced samples,so there is efficient flame retardancy in both ***,a tailoring of SCP based flame retardants is ***,these flame retardants efficiently reduce fiber degradation during combustion of carbon fiber-reinforced epoxy resins as observed by scanning electron microscopy and energy dispersive X-ray spectroscopy.

关键词： Epoxy resin composite fiber protection bio-based flame retardant

Resilience in Agriculture: Communication and Energy Infrastructure Dependencies of German Farmers

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International Journal of Disaster Risk Science 2022年第2期13卷 214-229页

作者： Franz Kuntke sebastian Linsner Enno Steinbrink Jonas Franken Christian Reuter Science and Technology for Peace and Security(PEASEC) Technical University of Darmstadt64289 Darmstadt.HesseGermany

Agriculture is subject to high demands regarding resilience as it is an essential component of the food production chain. In the agricultural sector, there is an increasing usage of digital tools that rely on communication and energy infrastructures. Should disruption occur,such strengthened dependencies on other infrastructures increase the probability of ripple effects. Thus, there is a need to analyze the resilience of the agricultural sector with a specific focus on the effects of digitalization. This study works out resilience capacities of the interconnected technologies used in farm systems based on the experiences and opinions of farmers. Information was gathered through focus group interviews with farmers(N = 52) and a survey with participants from the agricultural sector(N =118). In particular, the focus is put on the digital tools and other information and communication technologies they use. Based on a definition of resilience capacities, we evaluate resilience regarding energy and communication demands in various types of farm systems. Especially important are the resilience aspects of modern systems’ digital communication as well as the poorly developed and nonresilient network infrastructure in rural areas that contrast with the claim for a resilient agriculture. The result is a low robustness capacity, as our analysis concludes with the risk of food production losses.

关键词： Digitalization of agriculture Germany Infrastructure failures Resilience capacities

Combination strategies for pharmacologic treatment of nonalcoholic steatohepatitis

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World Journal of Gastroenterology 2022年第35期28卷 5129-5140页

作者： Jaspreet Suri sebastian Borja Joseph K Lim Department of Gastroenterology Norwalk HospitalNorwalkCT 06856United States Department of Internal Medicine Norwalk HospitalNorwalkCT 06850United States Section of Digestive Diseases Yale University School of MedicineNew HavenCT 06520United States

Non-alcoholic steatohepatitis (NASH) is defined as hepatic steatosis, inflammation,and hepatocyte injury with or without fibrosis. It has emerged as thesecond leading indication for liver transplantation with a rising death rate in thenon-transplantable population. While there are many drugs in evaluation,currently no approved therapies are on the market for this condition. Given thisimportance, the Food and Drug Administration has provided formal guidanceregarding drug development for stopping or reversing NASH or NASH associatedfibrosis. The complex pathogenesis of NASH and its bidirectional relationshipwith metabolic syndrome has highlighted multiple drugs of interest thataddress metabolic, inflammatory, and fibrotic factors. A few promising liverspecific targets include farnesoid X receptor agonists and peroxisome proliferatoractivatedreceptor agonists. Previously studied drug classes such as glucagon-likepeptide-1 analogs or sodium/glucose transport protein 2 inhibitors have alsodemonstrated ability to improve hepatic steatosis. Here we discuss currentrationale, scientific work, and preliminary data in combining multiple drugs forthe purposes of a multimodal attack on the pathogenesis of NASH. We highlightmultiple Phase 2 and Phase 3 studies that demonstrate the potential to achieve aresponse rate higher than previously assessed monotherapies for this ***, one of these combination strategies may rise above in its safety andefficacy to become a part of a standardized approach to NASH.

关键词： Non-alcoholic steatohepatitis Fatty liver Combination treatment Drug therapy Pharmacologic treatment Clinical trials