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Resilience in supply systems -What the food industry can learn from energy sector

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Journal of Safety Science and Resilience 2022年第1期3卷 39-47页

作者： Fabian Ossevorth Paul Seidel Sebastian Krahmer Joachim Seifert Peter Schegner Peter Lochmann Lukas Oehm Marc Mauermann technische universität Dresden Professur für ElektroenergieversorgungDresden 01069Germany technische universität Dresden Professur für Gebäudeenergietechnik und WärmeversorgungDresden 01069Germany technische universität Dresden Professur für Verarbeitungsmaschinen/VerarbeitungstechnikDresden 01069Germany Fraunhofer-Institut for Process Engineering and Packaging IVV Division Processing Technology Dresden01069Germany

Drastic events such as pandemics,earthquakes or other disasters not only threaten the immediate living conditions of people but also indirect circumstances such as energy supply,infrastructure and food *** ensure that damage and failures in these areas do not lead to a disaster,special requirements are placed on this critical *** this context resilience,which is defined as the resistance of a system to external effects,is required.A field that is indeed part of the critical infrastructure,but which has not been considered as intensively as the energy sector,is food *** investigation focuses on how fundamental principles of thermodynamics,system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of *** known state and process variables from thermodynamics and electrical power engineering,analogous variables are derived for the food *** variables serve as an evaluation standard for a quality measure𝑄.In addi-tion to system-theoretical considerations,it is investigated how existing evaluation criteria of power engineering,such as System Average Interruption Duration Index(SAIDI)and Customer Average Interruption Duration Index(CAIDI),can be transferred to food ***:the investigation focuses on how fundamental principles of thermodynamics,system theory and reliability theory can be applied to the modelling of food production processes to obtain a measure of *** known state and process variables from thermodynamics and electrical power engineering,analogous variables are derived for the food ***:Drastic events such as pandemics,earthquakes or other disasters not only threaten the immediate living conditions of people but also indirect circumstances such as energy supply,infrastructure and food *** ensure that damage and failures in these areas do not lead to a disaster,special requirements are placed on t

关键词： Resilience Food industry Energy Sector System theory

A CO and CO2 tolerating (La0.9Ca0.1)2(Ni0.75Cu0.25)O4+δ Ruddlesden-Popper membrane for oxygen separation

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Frontiers of Chemical Science and Engineering 2020年第3期14卷 405-414页

作者： Guoxing Chen Marc Widenmeyer Binjie tang Louise Kaeswurm Ling Wang Armin Feldhoff Anke Weidenkaff Institute of Materials Science Technische Universität Darmstadt64287 DarmstadtGermany Institute of Physical Chemistry and Electrochemistry Leibniz Universität Hannover30167 HannoverGermany Institute for Materials Science Universität Stuttgart70569 StuttgartGermany Fraunhofer Institute IWKS 63457 HanauGermany

A series of novel dense mixed conducting ceramic membranes based on K2NiF4-type(La1-xCax)2(Ni0.75Cu0.25)O4+δwas successfully prepared through a sol-gel *** chemical compatibility,oxygen permeability,CO and CO2 tolerance,and long-term CO2 resistance regarding phase composition and crystal structure at different atmospheres were *** results show that higher Ca contents in the material lead to the formation of CaCO3.A constant oxygen permeation flux of about 0.63 mL·min−1·cm−2 at 1173 K through a 0.65 mm thick membrane was measured for(La0.9Ca0.1)2(Ni0.75Cu0.25)O4+δ,using either helium or pure CO2 as sweep *** oxygen fluxes with no sign of deterioration of this membrane were observed with increasing CO2 *** membrane showed excellent chemical stability towards CO2 for more than 1360 h and phase stability in presence of CO for 4 h at high *** addition,this membrane did not deteriorate in a high-energy CO2 *** present work demonstrates that this(La0.9Ca0.1)2(Ni0.75Cu0.25)O4+δmembrane is a promising chemically robust candidate for oxygen separation applications.

关键词： K2NiF4 structure oxygen permeation membrane CO2 and CO resistances CO2 plasma resistance long-term robustness

UNIFORM SUPERCONVERGENCE OF A FINItE ELEMENt MEtHOD WItH EDGE StABILIZAtION FOR CONVECtION-DIFFUSION PROBLEMS

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Journal of Computational Mathematics 2010年第1期28卷 32-44页

作者： Sebastian Franz torsten Linβ Hans-Grg Roos Sebastian Schiller Department of Mathematics and Statistics University of Limerick Institut für Numerische Mathematik Technische Universitt Dresden

In the present paper the edge stabilization technique is applied to a convection-diffusion problem with exponential boundary layers on the unit square, using a Shishkin mesh with bilinear finite elements in the layer regions and linear elements on the coarse part of the mesh. An error bound is proved for ‖πu-u^h‖Е, where πu is some interpolant of the solution u and uh the discrete solution. this supercloseness result implies an optimal error estimate with respect to the L2 norm and opens the door to the application of postprocessing for improving the discrete solution.

关键词： Convection-diffusion problems Edge stabilization FEM Uniform convergence Shishkin mesh.

Numerical Analysis of a System of Singularly Perturbed Convection-Diffusion Equations Related to Optimal Control

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Numerical Mathematics(theory,Methods and Applications) 2011年第4期4卷 562-575页

作者： Hans-Görg Roos Christian Reibiger technische universität Dresden Institut für Numerische Mathematik01062 DresdenGermany

We consider an optimal control problem with an 1D singularly perturbed differential state *** solving such problems one uses the enhanced system of the state equation and its adjoint ***,we obtain a system of two convectiondiffusion *** linear finite elements on adapted grids we treat the effects of two layers arising at different boundaries of the *** proof uniform error estimates for this method on meshes of Shishkin *** present numerical results supporting our analysis.

关键词： Convection-diffusion linear finite elements a priori analysis layer-adapted meshes singular perturbed optimal control

水分和二氧化碳引起的水泥陈化对混凝土和砂浆中化学掺合料性能的影响(英文)

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硅酸盐学报 2014年第2期42卷 127-134页

作者： E DUBINA J PLANK technische universitt München

本工作旨在深入研究水泥的陈化对水泥与化学外加剂相互作用的影响。将Portland水泥分别暴露于35℃和相对湿度为90%的环境中1和3d。选取3种高效减水剂(萘系减水剂NSF、聚羧酸减水剂PCE和干酪素)、1种保水剂(MHEC,甲基纤维素)及两种促凝剂... 详细信息

本工作旨在深入研究水泥的陈化对水泥与化学外加剂相互作用的影响。将Portland水泥分别暴露于35℃和相对湿度为90%的环境中1和3d。选取3种高效减水剂(萘系减水剂NSF、聚羧酸减水剂PCE和干酪素)、1种保水剂(MHEC,甲基纤维素)及两种促凝剂(甲酸钙和无定形氧化铝),研究了水泥与化学外加剂的相互作用。结果表明:水泥的陈化显著改变了新拌浆体的流动性、保水性与凝结行为。由于暴露过程中水泥表面部分水化,水泥的比表面积以及表面电荷均发生变化,进而影响了水泥与化学外加剂的相互作用。具体表现在以下3个方面:1)与新鲜水泥相比,减水剂在陈化水泥中的减水效果减弱,干酪素的分散能力略微降低,而PCE和PNS的分散能力均显著下降,尤其是PNS下降最大;2)陈化水泥呈现较好的保水能力和更高的需水量,因此,为了达到相同的保水效果,其所需的保水剂掺量较新鲜水泥低;3)在陈化水泥中,甲酸钙和无定形氧化铝的促凝效果显著下降,在水泥陈化3d后,这些促凝剂甚至可能延缓水泥水化。

关键词：水泥陈化水分碳化外加剂

MXene based non-noble metal catalyst for overall water splitting in alkaline conditions

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Journal of Energy Chemistry 2023年第12期87卷 518-539,I0014页

作者： Dezheng Guo Qiwen Pan thomas Vietor Weijun Lu Yuan Gao Automotive Institute Tongji UniversityShanghai 200000China Institute of Engineering Design Technische Universität BraunschweigBraunschweig 38106Germany

MXene,the two-dimensional transition metal carbide or nitride material,was first discovered in *** possess superior characteristics such as stability,electric conductivity,and electrochemical properties,that make them attract the attention of the energy engineering *** water splitting which generates hydrogen and oxygen,not only serves as a clean energy supply technology but also demonstrates the capacity for redistribution and integration of renewable *** based non-noble metal has demonstrated significant potential in terms of ***,the current focus is implementing targeted regulation at the micro level to render it effective comparable to the precious *** this context,the mechanisms of the hydrogen evolution reaction(HER) and the oxygen evolution reaction(OER) under the influence of MXene can be elucidated in terms of electron and ion transfer processes,hydrogen coverage,and regulation of terminal ***,the composition,structure,synthesis,and stability strategies of MXene are the subjects of comprehensive investigation from both theoretical calculations using density functional theory(DFt) and experimental *** addition,this review provides a comprehensive summary of MXene based non-noble metal and various modification *** methods encompass doping,vacancy engineering,hybrid structures,heterojunction formation,multi-scale engineering,surface engineering,and phase *** review also presents suggestions for designing high-performance MXene based on non-noble *** offers guidance on employing construction strategies for *** leveraging the unique properties and tunability of MXene and implementing these modification methods,researchers can enhance the catalytic activity,stability,selectivity,and efficiency of MXene based non-noble metal catalysts.

关键词： MXene Overall water splitting Non-noble metal

Quasi-optimal control of a solar thermal system via neural networks✩

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Energy and AI 2023年第2期12卷 128-144页

作者： Jana Friese Niklas Brandt Andreas Schulte Christian Kirches Wilhelm tegethoff Jürgen Köhler technische universität Braunschweig Institut für ThermodynamikHans–Sommer–Straße 538106 BraunschweigGermany technische universität Braunschweig Institut für Mathematische OptimierungUniversitätsplatz 238106 BraunschweigGermany

the optimal control of complex thermal energy systems is a challenge due to their dynamic behavior andconstantly changing boundary conditions. to maximize the energy efficiency of such a dynamic system, optimaltrajectories for the controlled variables are needed. Extensive system knowledge is required to model the systemaccurately enough to be able to compute optimal trajectories. the high computational cost of computingoptimal control solutions with traditional approaches, especially with changing boundary conditions, oftenmakes this approach unusable for applications with limited computational power, such as real-time applicationson electronic control units (ECUs). this study investigates a possible solution to this challenge using a simplifiedexample system. Optimal control solutions for different boundary and initial conditions are generated forthe selected solar thermal system using a direct multiple shooting algorithm. Based on Bellman’s optimalityprinciple, the generated solutions are transformed into a data set of optimal state–action pairs. On this basis,different types of neural networks are trained, specifically a feed-forward, a recurrent, and a radial basisfunction network. thus, data generation and training can be performed offline, and the required online computations are significantly reduced since the evaluation of a trained neural network requires comparatively lowcentral processing unit (CPU) power. the trained neural network controllers are tested for their ability to outputnear-optimal control actions based on the current system state. the feed-forward and recurrent neural networksshow promising initial results in this regard. Open questions and the need for improvements are discussed.

关键词： Optimal control Neural networks Bellmann equation thermal systems Optimization

Light Induced Inhibition of Protein Phosphatase Calcineurin

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Chinese Journal of Chemistry 2014年第10期32卷 1011-1014页

作者： Andres Quintero Weilin Lin Sophia Hermann Yixin Zhang BCUBE Center for Molecular Bioengineering Technische Universität DresdenArnoldstrasse 1801307 DresdenGermany

Light-induced switching of drug activity can be used to realize spatio-temporal control of biological activity in cells and in *** our study of light-switchable derivatives of immunosuppressive drug cyclosporin A(CsA)in their inhibition of protein phosphatase calcineurin(CaN),we have discovered that 7-methyl-6-thioguanosine(MESG)inhibits CaN under light irradiation through a photo-crosslinking *** inhibition has shown selectivity over other enzymes such as phosphatase PP2A,protease chymotrypsin,and cyclophilin 18,the receptor protein for *** discovery could pave the way to discover new covalent inhibitors for protein phosphtase,to design immunophilin-independent CaN inhibitors,and to design new light controlled inhibitors to modulate signal transduction.

关键词： inhibitor photo-switching immunosuppression calcineurin phosphatase

Helicobacter pylori vaccination:Is there a path to protection?

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World Journal of Gastroenterology 2014年第34期20卷 11939-11949页

作者： Florian Anderl Markus Gerhard Institute for Medical Microbiology Immunology and HygieneTechnische Universit?t MünchenMunich 81675Germany

Helicobacter pylori (H. pylori) is a pathogenic, extracellular bacterium that colonizes the stomach in approximately 50% of the world population. It strongly interacts with the gastric epithelium and mostly causes asymptomatic gastritis. the colonization of H. pylori leads to ulcer development in around 20% of infected patients and may progress to gastric cancer or mucosa-associated lymphoid tissue lymphoma in 1%. thus, H. pylori is the major cause of gastric cancer worldwide. It has been classified as a class I carcinogen by the World Health Organization. Since its discovery in the early eighties by Warren and Marshall, research has been focused on the investigation of H. pylori biology, host-pathogen interaction, prevention and treatment. Although H. pylori induces a strong humoral and local cellular immune response, the pathogen is not cleared and establishes a chronic infection after encounters in childhood. the ability to colonize the stomach is mediated by several virulence factors that change the host environment, promote adhesion to the epithelium, influence the gastric inflammation and induce immune evasion. H. pylori can be eradicated by antibiotic treatment in combination with a proton-pump inhibitor, but efficacy is decreasing. Current therapies are expensive, have side effects and contribute to increasing antibiotic resistance, underlining the need for novel therapeutics.

关键词： Helicobacter pylori Vaccination Immune response Dendritic cells t-cells