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Environmental Impacts of the Yangtze Three gorges Project: An Overview of the Chinese-german Research Cooperation

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Journal of Earth Science 2010年第6期21卷 817-823页

作者： günter Subklew Julia Ulrich Leander fürst Agnes Hltkemeier forschungszentrum Jülich gmbH

The construction of the Three gorges Dam on the Yangtze River in China has a great influence on the ecosystems involved. In order to investigate these environmental effects in the Yangtze catchment area as well as downstream of the dam, forschungszentrum Julich has organized a research network for the Chinese and germaa partners. In the research fields of （1） interaction water/ sediment/contaminants, （2） vegetation/biodiversity, （3） changing land use/erosion/mass movements, and （4） atmosphere, the partners have accumulated a great deal of expertise in handling major issues and also in developing models and recommendations for action. The following provides an overview of the research network and the research tasks. On the german side, five projects in research field （3） have been in operation since 2008. The results are reported in contributions by Ehret et al., Jaehnig and Cai, Schonbrodt et al., and Seeber et al.. Another five projects in research field （1） have started by September 2010. The research tasks undertaken in these five projects are presented below.

关键词： Three gorges Dam Yangtze River environmental research ecosystem.

Ce anomaly in minerals of eclogite and garnet pyroxenite from Dabie-Sulu ultrahigh pressure metamorphic belt:Tacking subducted sediment formed under oxidizing conditions

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Science China Earth Sciences 2004年第10期47卷 920-930页

作者： Deltlef günther Institute of Inorganic Chemistry ETHZürichUniversitatsstrasse6CH-092ZürichSwitzerland

In-situ excimer laser ICP-MS analysis of minerals of eclogites and garnet pyrox- enites from type localities (Shuanghe, Maowu, Bixiling, and Yangkou) in the Dabie-Sulu ultra- high-pressure metamorphic belt reveals highly variable Ce anomalies from negative to positive in garnet. Similar Ce anomalies are also present in omphacite or clinopyroxene but to a much lesser extent. Such mixed negative and positive Ce anomalies mimic those found in severe weathering profiles developed under oxidizing conditions. They suggest the presence of sub- ducted sediment components in the eclogites and garnet pyroxenites, which in turn points to the potential importance of the recycled sediments in modification of the mantle composition during the deep subduction of the continental crust.

关键词： Dabie-Sulu, eclogite, garnet pyroxenite, LA-ICP-MS, subducted sediment, Ce anomaly.

Surface chemistry of nanoscale fe_3O_4 dispersed in magnetic fluids

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Science China Chemistry 2007年第6期50卷 754-758页

作者： Bernd günther fraunhofer Institut für fertigungstechnik und Angewandte Materialforschung D-28359 Bremen Germany

The interaction between stabilizers and nanoparticles is one of the important factors to prepare stable magnetic fluids. The magnetic nano-size fe3O4 core with single domain and the average grain size around 8-12 nm were prepared by chemical precipitation method. The O/fe molar ratio of the particle surface was measured by X-ray photoelectron spectroscopy (XPS). The heat effects of stabilizers ad- sorption on nanoparticles were measured by solution calorimetry. The excess amount of oxygen was possibly the result of the hydroxygen formed on the surface of the nanoparticles. The heat effects showed that compounds containing carboxyl groups can be adsorbed chemically on magnetite by forming chemical bonds. The other stabilizers involving NH-groups, such as polyethylene-imine, can be adsorbed physically. The exothermic value is about half of the former case.

关键词： nanoscale materials heat effect magnetic fluids surface chemistry

3D flow Past Transonic Turbine Cascade SE 1050-Experiment and Numerical Simulations

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Journal of Thermal Science 2013年第4期22卷 311-319页

作者： D.imurda J.fürst M.Luxa Institute of Thermomechanics AS CR v.v.i.Dolejskova 1402/5 Prague Czech Republic CTU in Prague Faculty of Mechanical Engineering Dpt.of Technical MathematicsKarlovo Náměstí 13 Prague Czech Republic

This paper is concerned with experimental and numerical research on 3D flow past prismatic turbine cascade SE1050 （known in QNET network as open test case SE1050）. The primary goal was to assess the influence of the inlet velocity profile on the flow structures in the interblade channel and on the flow field parameters at the cascade exit and to compare these findings to results of numerical simulations. Investigations of 3D flow past the cascade with non-uniform inlet velocity profile were carried out both experimentally and numerically at subsonic （M2 = 0.8） and at transonic （M2 = 1.2） regime at design angle of incidence. Experimental data was obtained using a traversing device with a five-hole conical probe. Numerically, the 3D flow was simulated by open source code OpenfOAM and in-house code. Analyses of experimental data and CfD simulations have revealed the development of distinctive vortex structures resulting from non-uniform inlet velocity profile. Origin of these structures results in increased loss of kinetic energy and spanwise shift of kinetic energy loss coefficient distribution. Differences found between the subsonic and the transonic case confirm earlier findings available in the literature. Results of CfD and experiments agree reasonably well.

关键词： blade cascade vortex structures transonic flow CfD

Numerical simulation of three dimensional concrete printing based on a unified fluid and solid mechanics formulation

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frontiers of Structural and Civil Engineering 2024年第4期18卷 491-515页

作者： Janis REINOLD Koussay DAADOUCH günther MESCHKE Institute for Structural Mechanics Ruhr University BochumBochum 44801Germany

Deformation control constitutes one of the main technological challenges in three dimensional(3D)concrete printing,and it presents a challenge that must be addressed to achieve a precise and reliable construction ***-based information of the expected deformations and stresses is required to optimize the construction process in association with the specific properties of the concrete *** this work,a novel thermodynamically consistent finite strain constitutive model for fresh and early-age 3D-printable concrete is *** model is then used to simulate the 3D concrete printing process to assess layer shapes,deformations,forces acting on substrate layers and prognoses of possible structural collapse during the layer-by-layer *** constitutive formulation is based on a multiplicative split of the deformation gradient into elastic,aging and viscoplastic parts,in combination with a hyperelastic potential and considering evolving material properties to account for structural buildup or *** advantage of this model is the stress-update-scheme,which is similar to that of small strain plasticity and therefore enables an efficient integration with existing material *** constitutive model uses the particle finite element method,which serves as the simulation framework,allowing for modeling of the evolving free surfaces during the extrusion *** analyses of three printed layers are used to create deformation plots,which can then be used to control the deformations during 3D concrete *** study offers further investigations,on the structural level,focusing on the potential structural collapse of a 3D printed concrete *** capability of the proposed model to simulate 3D concrete printing processes across the scales—from a few printed layers to the scale of the whole printed structure—in a unified fashion with one constitutive formulation,is demonstrated.

关键词： particle finite element method 3D concrete printing multiplicative split additive manufacturing elastoviscoplasticity

Dissolution and grain growth of nano-Ag-Cu alloy

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Chinese Science Bulletin 1997年第2期42卷 166-169页

作者： A. günther fraunhofer Institut fur Angrwandte Materialforschung Bremen D-28717 Germany

NANOPHASE materials (nc-) was first introduced by gleiter and his coworkers, who prepared these materials using inert gas condensation technique (IgC) which were then compressed in situ by vacuum die pressing. The average grain diameters were in the range of 4-15 nm and measured by X-ray diffraction (XRD). for nc materials, the peak of XRD is broadening due to the small grain sizes and internal stresses caused by lattice deformation. In binary alloys prepared by IgC, supersaturation as well as nonequilibrium may also

关键词： nanograin (nanocrystallite) supersaturated solid solution dissolution activation energy.

An SPH framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

APPROACHES fOR SUSTAINABLE MANUfACTURINg

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Chinese Journal of Mechanical Engineering 2007年第1期20卷 86-90页

作者： günther Seliger SEBASTIAN Kernbaum MARCO Zettl Department Assembly Technology and factory Management Institute for Machine Tools and Factory Management Technical University Berlin Berlin 10587 Germany

Sustainable development is a holistic approach harmonizing ecological, economical and socio-political needs with respect to the superior objective of enhancing human living standards. Thereby the availability of natural resources and the conservation of the ecosystems have to be considered that future generations have the possibility to meet their own needs. A long-term economical development demands the transition from a souree-sink economy to a cycle economy as a result of limited resources, limited environmental capacities to absorb waste and emissions as well as increasing needs of a growing population. A reference model for snstainability in manufacturing is presented and used to illustrate sustainable approaches with respect to management, technology, process and product. Adaptation of products and components is a vital element for supporting efficient reuse of products and components. Consequently adaptation contributes to the ambitions goals of snstainability. Technological enablers for adaptation as modularity, information and communication technology are exemplarily introduced. Moreover, approaches for disseminating knowledge in sustainability are given.

关键词： Sustainability Manufacturing Adaptation Modularization Life cycle unit

NARRATINg CHECKS AND BALANCES?THE SETUP Of fINANCERELATED ADMINISTRATIVE DOCUMENTS AND INSTITUTIONS IN 5TH AND 4TH CENTURY BC ATHENS

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Journal of Ancient Civilizations 2019年第2期34卷 211-227,328页

作者： Sven günther IHAC NENUChangchun

The setup and narratives of finance-related administrative documents and powers tell the story and fate of the Athenian *** the one hand,one can see the permanently repeated and impressive statement of stability that did not only astonish contemporaries,especially critics of the democratic *** was mirrored in the frequent publication of financial *** were more representative in various aspects than informative in the sense of a real transparent ***,the many offices mentioned both in the literary and epigraphic documents reflect the constant mistrust in,and restriction of,the accumulation of power in the democratic *** the other hand,these formalities and standardized formulas do clearly not carry the whole story,and are superseded in the course of the 4th century by informal powerconglomerations.

关键词： SETUP finance statement