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Absorptive Capacities for Sustainability Technologies:Perspectives from the BRICS and China

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Chinese Journal of Population,Resources and Environment 2009年第2期7卷 3-10页

作者： Rainer Walz Katrin Ostertag fraunhofer institute Systems and Innovation Research Breslauerstr.48KarlsruheGermany institute for Policy and Management CAS

For the development process in the rapidly growing economies, knowledge transfer and technology cooperation are becoming important issues. Research and technological competences are key indicators for the absorptive capacity of sustainability technologies and for the ability to export them. These issues are analyzed empirically for Brazil, Russia, India, China and South Africa (BRICS). Sustainability related research in BRICS is mostly carried out within broader, more sector oriented programmes. Specialization patterns of international patents and in foreign trade indicate various strengths and weaknesses of the BRICS countries. The differences within the countries imply that the analysis must proceed at a technology specific level. China has considerable capabilities in technologies such as photovoltaics, solar thermal or buildings. There is a strong need for strategic positioning of the countries and for coordination of the various policy fields involved.

关键词： sustainability technologies innovation absorptive capacities BRICS

Fe/Co and Ni/Co-pentlandite type electrocatalysts for the hydrogen evolution reaction

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Chinese Journal of Catalysis 2021年第8期42卷 1360-1369页

作者： Mathias Smialkowski David Tetzlaff Lars Hensgen Daniel Siegmund Ulf-Peter Apfel Inorganic Chemistry I-Ruhr University Bochum Universitätsstrasse 15044801 BochumGermany fraunhofer umsicht Osterfelder Strasse 346047 OberhausenGermany Tribotecc GmbH Fleischmarkt 3-51010 ViennaAustria

Metal-rich transition metal sulfides recently gained increasing attention as electrocatalysts for the hydrogen evolution reaction(HER),as they are capable to overcome major challenges faced by sulfide-rich metal catalysts such as limited conductivity and the necessity of ***,we present the synthesis,characterization and electrocatalytic investigation of ternary metal-rich sulfide composites FexCo9-xS8 as well as Ni_(y)Co_(9-y)S_(8)(x=y=0-4.5),which possess pentlandite-type *** this study,we show a stepwise alteration of the binary cobalt pentlandite Co9S8 and report on the replacement of cobalt with up to 4.5 equivalents of either iron or *** altered pentlandite composites facilitate the proton reduction in acidic media at different *** furthermore show that the stoichiometric variation has a decisive influence on the electrochemical activation/deactivation behavior of the catalysts under reductive electrocatalytic ***,Co-deficient composites display an improved HER performance in contrast to Co_(9)S_(8).Notably,Ni/Co compounds generally tend to show higher catalytic activities towards HER than their respective Fe/Co compounds.

关键词： Hydrogen Pentlandite Metal sulfides Transition metals Electrocatalysis

Methane Production, Emission and Possible Control Measures in the Rice Agriculture

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Advances in Atmospheric Sciences 1993年第3期10卷 307-314页

作者：王明星上官行健沈壬兴 Wassmann Reiner Seiler Wolfgang institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 fraunhofer institute for Atmospheric Environmental Research F.R. Germany

In the rice field methane is produced in the soil layer with depths of 2-25 cm. The vertical profile of methane production rate in the paddy soil during the water covering period differs from that in the paddy soil in dry phase. Only a small part, about 30%. of the produced methane is emitted to the atmosphere through rice plant, air bubbles, and molecular diffusion. Therefore, the methane emission rate from the rice field depends not only on the methane production rate in the soil, but also on the transport efficiency of the rice plant, air bubble formation that in turn depends on the production rate, and molecular *** measurements show that methane emission rates from a particular rice field have very large diurnal, seasonal and interannual variations, which are related to soil characteristics, water regime, farming procedure, local climate, and rice growing activities. The relationship between the methane emission rate and the above mentioned factors is very complicated. The emission rates from different rice fields differ greatly not only in the absolute value, but also in the temporal variation *** emission rate from the rice field may be significantly reduced by scientific management of fertilizer and irrigation. While the use of SO42- containing fertilizer and fermented organic fertilizer may reduce the methane emission significantly, the most promising measure for reducing methane emission from rice field is the frequent drainage irrigation procedure.

关键词： Methane Production Emission

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

Science Letters:Three-dimensional conceptual model for service-oriented simulation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第8期10卷 1075-1081页

作者： Wen-guang WANG Wei-ping WANG Justyna ZANDER Yi-fan ZHU College of Information System and Management National University of Defense Technology Changsha 410073 China fraunhofer institute FOKUS Kaiserin-Augusta-Allee 31 Berlin 10589 Germany

In this letter,we propose a novel three-dimensional conceptual model for an emerging service-oriented simulation paradigm. The model can be used as a guideline or an analytic means to find the potential and possible future directions of the current simulation frameworks. In particular, the model inspects the crossover between the disciplines of modeling and simulation, service-orientation,and software/systems engineering. Finally, two specific simulation frameworks are studied as examples.

关键词： Conceptual model Modeling and simulation Service-oriented architecture Systems engineering

Effects of welding speed on the multiscale residual stresses in frictionstir welded metal matrix composites

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Journal of Materials Science & Technology 2019年第5期35卷 824-832页

作者： X.X.Zhang L.H.Wu H.ANDra W.M.Gan M.Hofmann D.Wang D.R.Ni B.L.Xiao Z.Y.Ma Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China fraunhofer institute for Industrial Mathematics Fraunhofer-Platz 1 Kaiserslautern 67663 Germany German Engineering Materials Science Centre Helmholtz-Zentrum Geesthacht D-21502 Geesthacht Germany Heinz Maier-Leibnitz Zentrum (MLZ) Technische Universitat Munchen D-85747 Garching Germany

The effects of welding speed on the macroscopic and microscopic residual stresses(RSes) in friction stir welded 17 vol.% SiCp/2009 Al-T4 composite plates were studied via neutron diffraction and an improved decoupled hierarchical multiscale modeling methods. Measurements showed that the macroscopic and total RSes had the largest variations in the longitudinal direction(LD). Increasing the welding speed led to higher values of measured LD macroscopic and total RSes in the matrix. The welding speed also significantly influenced the distributions and magnitudes of the microscopic RSes. The RSes were predicted via an improved hierarchical multiscale model, which includes a constant coefficient of friction based thermal model. The RSes in the composite plates before friction stir welding(FSW) were computed and then set as the initial states of the FSW process during modeling. This improved decoupled multiscale model provided improved predictions of the temperature and RSes compared with our previous model.

关键词： Metal-matrix composites (MMCs) Friction stir welding Residual/internal stress Neutron diffraction Finite element analysis (FEA) Multiscale simulation

CAD-VR geometry and meta data synchronization for design review applications

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1482-1491页

作者： SCHILLING Arne KIM Seokryul WEISSMANN Daniel TANG Ziying CHOI Sangsu fraunhofer institute for Computer Graphics （IGD） Darmstadt 64283 Germany institute for Graphic Interfaces （IGI） Seou1120-750 Korea Computer Graphics Center （ZGD V） Rostock 18059 Germany

In this paper we present the MEMPHIS middleware framework for the integration of CAD geometries and assemblies with derived Virtual Reality (VR) models and its specific meta data and attributes. The goal of this work is to connect real time VR applications, especially for the Design Review, with enterprise software storing and managing CAD models (Product Data Man- agement—PDM). The preparation of VR models requires expert knowledge, is time consuming, and includes selection of required CAD data, tessellation, healing of unwanted gaps, applying materials and textures, and special surface and light effects. During the Design Review process, decisions are made concerning the choice of materials and surface forms. While materials can be switched directly on the VR model, the modification of part geometries must be made on the CAD model. Our system synchronizes modi- fications of the original CAD geometries and of attributes that are relevant for the realistic rendering using the PLM Services standard. Thus, repeated work for the VR preparation can be avoided.

关键词： Virtual Reality (VR) CAD Product Data Management (PDM) Geometry conversion

On the calibration of rotational augmentation models for wind turbine load estimation by means of CFD simulations

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Acta Mechanica Sinica 2020年第2期36卷 306-319页

作者： Belen Soledad Burgos Tafur Elia Daniele Bernhard Stoevesandt Philipp Thomas fraunhofer IWES Am Seedeich 4527572 BremerhavenGermany Flensburg University of Applied Sciences Wind Energy Technology InstituteNordstraße224943 FlensburgGermany

In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and *** on an analysis of the NREL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and *** model is calibrated based on CFD simulations using *** corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load *** novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few *** optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the *** the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.

关键词： calculation. rotational correction

Speciation in nanosecond laser ablation of zinc in water

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 90-98页

作者： Stefan Reich Yannis Klügl Anna Ziefuss RenéStreubel Jorg Gottlicher Anton Plech institute for Photon Science and Synchrotron Radiation Karlsruhe Institute of TechnologyKarlsruhe D-76021Germany Department of Technical ChemistryⅠand Center for Nanointegration Duisburg-Essen University of Duisburg-EssenEssen D-45141Germany fraunhofer institute for High-Speed Dynamics Ernst-Mach-Institute(EMI)Freiburg 79104Germany

In situ experimental methods have been applied to resolve mass flow and chemical speciation in the pulsed laser ablation of zinc in water. The chemical speciation has been resolved by time-resolved μ-X-ray absorption spectroscopy and mapped onto the macroscopic mass flow during material ejection from the metallic target and bubble dynamics of evaporated water. Large particles and agglomerates have been detected via dark-field X-ray imaging with a Shack-Hartmann sensor. The characteristic of the dynamics is that the vapor bubble is nearly homogeneously filled with ablated material. This persists during bubble collapse,which means that the ablated particles are captured and retracted towards the target. Limited mass escape is indicated by the X-ray absorption signal. Importantly, the near-edge structure at the Zn-K;transition delivers information on the chemical state of the ejected material. It clearly confirms that oxidation is not present within the bubble phase and the following sub-millisecond time scale. The oxidation proceeds on Zn nanoparticles in suspension on a second to minute course. Within the first microseconds,a Zn atom phase is detected that resembles Zn vapor. The addition of either reductive NaBH;or oxidative HAuCl;to the water phase influences the quantity of the atom contribution moderately, but does not influence the initial atom phase. Such behavior must be understood in terms of the nanosecond pulse excitation. After ejected material and a plasma is formed within the pulse duration of 7 ns the laser is able to further heat the ejecta and transform it partly into vapor. Correspondingly, the coupling of energy into the ablation zone as followed by plasma intensity and bubble size follows a threshold behavior as a function of laser fluence, marking the onset of laser-plasma heating. The reaction conditions inside the bubble are probably reductive due to the concomitant formation of excess hydrogen.

关键词： laser ablation in liquids elemental speciation X-ray absorption spectroscopy oxidation zinc oxide nanoparticles