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Journal of Environmental Sciences 2012年第9期24卷 1686-1693页

作者： Amina Chnirheb Mourad Harir Basem Kanawati Mohammed El Azzouzi Istvan Gebefgi Philippe Schmitt-Kopplin Department of BioGeoChemistry and Analytik German Research Center for Environmental HealthHelmholtz Center MunichIngoldstdter Landstraβe 1D-85764 NeuherbergGermany University Mohammed V-Agdal Faculty of SciencesAvenue Ibn BatoutaBP 1014 RabatMorocco. Lehrstuhl fr Chemische-Technische Analyse und Chemische Lebensmitteltechnologie Technische Universitt MuenchenWeihenstephaner Steig 2385354 Freising-WeihenstephanGermany

The photodegradation of mefenpyrdiethyl （MFD）, an herbicide safener, was investigated in aqueous suspensions by using Degussa P-25 and Hombikat UV100 titanium oxide under simulated sunlight irradiation. The effects of initial concentration of the herbicide, pH, catalysts and hydrogen peroxide doses as well as their combinations were studied and optimized. Accordingly, the kinetic parameters were determined and the effectiveness of the processes was assessed by calculating the rate constants. A pseudo first-order kinetics was observed. Under experimental conditions, the degradation rate constants were strongly influenced using P-25 and no noticeable effect was observed for Hombikat UV100. DFT calculations with B3LYP/6-311＋G（2d,p）//B3LYP/6-31＋G（d,p） level of theory were performed to check whether significant conformational changes occur when the charge state of the MFD substrate changes and whether these changes could play a role in the dependency of photodegradation rate constant on the studied pH. High resolution mass spectrometry （FT-ICR/MS） was implemented to identify the main degradation products.

关键词： photodegradation mefenpyrdiethyl P-25/Hombikat UV100 kinetic degradation products

High temperature tensile,compression and creep behavior of recycled short carbon fibre reinforced AZ91 magnesium alloy fabricated by a high shearing dispersion technique

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Journal of Magnesium and Alloys 2021年第5期9卷 1773-1787页

作者： Sinan Kandemir Sarkis Gavras Hajo Dieringa Department of Mechanical Engineering Izmir Institute of Technology35430UrlaIzmirTurkey Helmholtz-Zentrum Hereon MagIC-Magnesium Innovation CentreMax-Planck-Straße 121502GeesthachtGermany Helmholtz-Zentrum Hereon Institute of Metallic BiomaterialsMax-Planck-Straße 121502GeesthachtGermany Helmholtz-Zentrum Hereon Institute of Materials and Process DesignMax-Planck-Straße 121502GeesthachtGermany

The present study seeks the feasibility of using short carbon fibres recycled from polymer matrix composites as alternative to virgin carbon fibres in the reinforcement of magnesium *** microstructures,high temperature mechanical and creep properties of AZ91 alloy and its composites with various recycled carbon fibre contents(2.5 and 5 wt.%)and lengths(100 and 500μm)were investigated in the temperature range of 25-200℃.The microstructural characterization showed that the high shear dispersion technique provided the cast composites with finer grains and relatively homogenous distribution of *** materials tested displayed different behaviour depending on the type of *** general,while enhancements in the mechanical properties of composites is attributed to the load bearing and grain refinement effects of fibres,the fluctuations in the properties were discussed on the basis of porosity formation,relatively high reinforcement content leading to fibre clustering and interlayer found between the matrix and reinforcement compared to those of AZ91 *** compressive creep tests revealed similar or higher minimum creep rates in the recycled carbon fibre reinforced AZ91 in comparison to the unreinforced AZ91.

关键词： Metal matrix composites Magnesium alloys Recycled carbon fibre High-shear dispersion Microstructure Mechanical properties Creep

Corrosion behavior of metallic alloys in molten chloride salts for thermal energy storage in concentrated solar power plants： A review

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 564-576页

作者： Wenjin Ding Alexander Bonk Thomas Bauer Institute of Engineering Thermodynamics German Aerospace Center (DLR) 70569 Stuttgart Germany Institute of Engineering Thermodynamics German Aerospace Center (DLR) 51147 Cologne Germany

Recently, more and more attention is paid on applications of molten chlorides in concentrated solar power （CSP） plants as high-temperature thermal energy storage （TES） and heat transfer fluid （HTF） materials due to their high thermal stability limits and low prices, compared to the commercial TES/HTF materials in CSP- nitrate salt mixtures. A higher TES/HTF operating temperature leads to higher efficiency of thermal to electrical energy conversion of the power block in CSP, however causes additional challenges, particularly increased corrosiveness of metallic alloys used as contain- ers and structural materials. Thus, it is essential to study corrosion behaviors and mechanisms of metallic alloys in molten chlorides at operating temperatures （500-800℃） for realizing the commercial application of molten chlorides in CSE The results of studies on hot corrosion of metallic alloys in molten chlorides are reviewed to understand their corrosion behaviors and mechanisms under various conditions （e.g., temperature, atmosphere）. Emphasis has also been given on salt purification to reduce corrosive impurities in molten chlorides and development of electrochemical techniques to in-situ monitor corrosive impurities in molten chlorides, in order to efficiently control corrosion rates of metallic alloys in molten chlorides to meet the requirements of industrial applications.

关键词： corrosion mechanisms impurities metallic corrosion salt purification electrochemical techniques

Time-frequency multiresolution of fault-generated transient signals in transmission lines using a morphological filter

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Protection and Control of Modern Power Systems 2023年第2期8卷 85-98页

作者： Juan Carlos Quispe John Morales Eduardo Orduna Carlo Liebermann Michael Bruhns Peter Schegner Universidad Nacional de San Juan-CONICET San JuanArgentina Universidad Tecnológica del Perú LimaPerú Technical University of Dresden DresdenGermany

The ongoing transformation of electrical power systems highlights the weaknesses of the protection schemes of traditional devices because they are designed and configured according to traditional characteristics of the ***,this work proposes a new methodology to study the fault-generated high frequency transient signals in transmission lines through multiresolution *** high frequency components are determined by a new digital filtering technique based on mathematical morphology theory and a spectral energy ***,wide spectra of signals in the time–frequency domain are *** performance of this method is verified on an electrical power system modeled in ATP-Draw,where simulation and test signals are developed for different locations,fault resistances,inception angles,high frequency noises,sampling frequencies,types of faults,and shapes of the structuring *** results show the characteristics of the fault such as the traveling wave frequency,location,and starting time.

关键词： Digital filter High frequency Mathematical morphology Time–frequency Traveling waves

Human iPSC-derived iMSCs improve bone regeneration in mini-pigs

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Bone Research 2019年第4期7卷 399-409页

作者： Pascal Jungbluth Lucas-Sebastian Spitzhorn Jan Grassmann Stephan Tanner David Latz Md Shaifur Rahman Martina Bohndorf Wasco Wruck Martin Sager Vera Grotheer Patric Kropil Mohssen Hakimi Joachim Windolf Johannes Schneppendahl James Adjaye Department of Trauma and Hand Surgery Heinrich Heine University Hospital DüsseldorfMoorenstr.540225 DüsseldorfGermany Institute for Stem Cell Research and Regenerative Medicine Medical FacultyHeinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany Animal Research Institute Heinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany Department of Diagnostic and Interventional Radiology Medical FacultyHeinrich Heine UniversityDüsseldorfMoorenstr.540225 DüsseldorfGermany Vivantes Klinikum Am Urban Dieffenbachstraβe 110967 BerlinGermany

Autologous bone marrow concentrate(BMC)and mesenchymal stem cells(MSCs)have beneficial effects on the healing of bone *** address the shortcomings associated with the use of primary MSCs,induced pluripotent stem cell(iPSC)-derived MSCs(iMSCs)have been proposed as an *** aim of this study was to investigate the bone regeneration potential of human iMSCs combined with calcium phosphate granules(CPG)in critical-size defects in the proximal tibias of mini-pigs in the early phase of bone healing compared to that of a previously reported autograft treatment and treatment with a composite made of either a combination of autologous BMC and CPG or CPG *** were derived from iPSCs originating from human fetal foreskin fibroblasts(HFFs).They were able to differentiate into osteoblasts in vitro,express a plethora of bone morphogenic proteins(BMPs)and secrete paracrine signaling-associated cytokines such as PDGF-AA and *** and histomorphometrically,HFF-iMSC+CPG transplantation resulted in significantly better osseous consolidation than the transplantation of CPG alone and produced no significantly different outcomes compared to the transplantation of autologous BMC+CPG after 6 *** results of this translational study imply that iMSCs represent a valuable future treatment option for load-bearing bone defects in humans.

关键词： healing alone treatment

Lenormandins A—G,new azaphilones from Hypoxylon lenormandii and Hypoxylon jaklitschii ***.,recognised by chemotaxonomic data

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Fungal Diversity 2015年第2期71卷 165-184页

作者： Eric Kuhnert Frank Surup Esteban B.Sir Christopher Lambert Kevin D.Hyde Adriana I.Hladki Andrea I.Romero Marc Stadler Department of Microbial Drugs Helmholtz-Zentrum für Infektionsforschung GmbHInhoffenstrasse 738124 BraunschweigGermany german Centre for Infection Research(DZIF) partner site Hannover-Braunschweig38124 BraunschweigGermany Fundación Miguel Lillo Institute of MycologyMiguel Lillo 251San Miguel de Tucumán 4000TucumánArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Av.Rivadavia 1917Buenos Aires C1033AAJArgentina Institute of Excellence in Fungal Research and School of Science Mae Fah Luang UniversityChiang Rai 57100Thailand Department of Biodiversity and Experimental Biology University of Buenos AiresInt.Güiraldes 2620Buenos Aires C1428EHAArgentina

Seven new azaphilone pigments named lenormandins A–G were isolated from stromata(fruiting bodies)of the xylariaceous fungus,Hypoxylon lenormandii using preparative High Performance Liquid Chromatography(HPLC)and their structures were elucidated by NMR spectroscopy,high resolution mass spectrometry and other spectral *** occurrence in herbarium specimens(including various type materials collected in the 19th and early 20th century)and several fresh collections was studied by analytical HPLC with diode array and mass spectrometric detection(HPLC-DAD/MS),revealing that this group of pigments is specific for Hypoxylon lenormandii from various geographic regions and otherwise only occurs in closely related taxa,*** and an undescribed fungus from Sri Lanka,for which we propose the name *** status of the new species was established by using molecular phylogenetic data based on ITS and partial beta-tubulin sequences,and by detailed morphological studies.

关键词： Chemotaxonomy Hypoxylon Phylogeny Secondary metabolites Systematics Xylariaceae

Significance of intercellular communication for neurodegenerative diseases

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Neural Regeneration Research 2022年第5期17卷 1015-1017页

作者： Hilal Cihankaya Carsten Theiss Veronika Matschke Ruhr University Bochum Medical FacultyInstitute of AnatomyDepartment of CytologyBochumGermany International Graduate School of Neuroscience(IGSN) Ruhr-University BochumBochumGermany

The nervous system is a highly complex organization composed of its basicunit,the neuronal cells,and specialized supporting cells,the glial *** main glial cells in the central nervous system(CNS)are astrocytes,microgl... 详细信息

关键词： cytes diseases degenerative

Remote heart rate measurement using low-cost RGB face video： a technical literature review

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Frontiers of Computer Science 2018年第5期12卷 858-872页

作者： Philipp V. ROUAST Marc T. P. ADAM Raymond CHIONG David CORNFORTH Ewa LUX Institute of Information Systems and Marketing Karlsruhe Institute of Technology Karlsruhe 76133 Germany School of Electrical Engineering and Computing The University of Newcastle Callaghan NSW 2308 Australia

Remote photoplethysmography （rPPG） allows remote measurement of the heart rate using low-cost RGB imaging equipment. In this study, we review the development of the field of rPPG since its emergence in 2008. We also classify existing rPPG approaches and derive a framework that provides an overview of modular steps. Based on this framework, practitioners can use our classification to design algorithms for an rPPG approach that suits their specific needs. Researchers can use the reviewed and classified algorithms as a starting point to improve particular features of an rPPG algorithm.

关键词： affective computing heart rate measurement remote non-contact camera-based photoplethysmography

Parameter identification and blanking simulations of DP1000 and Al6082-T6 using Lemaitre damage model

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Advances in Manufacturing 2021年第3期9卷 457-472页

作者： Sheng Cai Lin Chen Department of Vehicle Engineering College of EngineeringChina Agricultural UniversityBeijing100083People’s Republic of China CW Bearing GmbH 22113HamburgGermany

This work provides numerical and experimental investigations of blanking process,where the shear-enhanced Lemaitre’s damage model is fully characterized and successfully applied in blanking process to predict the cutting force and cutting edge geometry under different blanking process *** high strength steel DP1000 and an aluminum alloy Al6082-T6 are selected for series of *** obtain the damage parameters in Lemaitre’s damage model the flat rectangular notched specimens tensile test was conducted and the inverse parameter identification procedure was *** characterizing the crack closure parameter h in the shear enhanced Lemaitre’s damage model,an in-plane torsion test with novel specimen design was *** finite element model(FEM)of this test was established with the minimum mesh size of 0.01 mm which was consistent with the minimum mesh size in the shear zone of the FEM for blanking process *** longitudinal strain distributions of four kinds of initial notch radius or central-hole specimen were measured and compared with simulation results to validate the FEMs for these four *** analysis of blanking of a circular work piece also was performed under three *** effects of blanking conditions on sheared part morphology were *** triaxiality distribution of the blank sheet was revealed taking advantage of the successfully established *** availability of the testing method and the determination method of the parameters was investigated.

关键词： Blanking Lemaitre damage model Stress triaxiality Finite element model(FEM)

Remote Gully Erosion Mapping Using ASTER Data and Geomorphologic Analysis in the Main Ethiopian Rift

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Geo-Spatial Information Science 2011年第4期14卷 246-254页

作者： Moncef Bouaziz Arief Wijaya Richard Gloaguen Remote Sensing Group Institut für GeologieTU Bergakademie Freiberg Laboratoire 3E(AD‐10‐02) Ecole National d'Ingénieurs de Sfax Faculty of Agricultural Technology Gadjah Mada University

The Main Ethiopian Rift(MER)is an area of extreme topography underlain by post-Miocene volcanic rocks,Jurassic limestone and a Precambrian basement.A prime concern is the rapid expansion of wide gullies that are impinging on agricultural *** investigate the potential contribution of Advanced Space-borne Thermal Emission and Reflection Radiometer(ASTER)data and geomorphologic parameters to discern patterns and features of gully erosion in the *** Likelihood Classifica-tion(MLC),Support Vector Machine(SVM),and Minimum Distance(MD)classifiers are used to extract different gully shapes and *** spatial textures based on Grey Level Co-occurrence Matrices(GLCMs)are then ***,the same classifiers are applied to the ASTER data combined with the spatial texture *** used geomorphologic parameters ex-tracted from SRTM and ASTER DEMs to describe the geomorphologic setting and the gullies' *** classifications show accuracies varying between 67% and 89%.Maps derived from this quantitative analysis allow the monitoring and mapping of land degradation as a direct result of *** study reveals the utility of combining ASTER data and spatial textural infor-mation in discerning areas affected by gully erosion.

关键词： remote sensing gully erosion texture ASTER data