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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.

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.

Identification of digital technologies and digitalisation trends in the mining industry

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International Journal of Mining Science and Technology 2020年第6期30卷 747-757页

作者： Lars Barnewold bernd g.Lottermoser Institute of Mineral Resources Engineering RWTH Aachen University52062 AachenGermany

Digitalisation in mining refers to the use of computerised or digital devices or systems and digitised data that are to reduce costs,improve business productivity,and transform mining ***,it remains increasingly difficult for mining companies to decide which digital technologies are most relevant to their needs and individual *** paper provides an overview of digital technologies currently relevant to mining companies as presented and discussed by mining journals,the media and insight reports of leading consultancy *** technologies were systematically identified using text-mining techniques,and network analyses established the relations between significant *** demonstrated that currently 107 different digital technologies are pursued in the mining ***,an analysis of the actual implementation of digital technologies in 158 active surface and underground mines reveals a limited uptake of digital technologies in general and that the uptake increases with the run-of-mine ***-scale mining operations appear to select and apply digital technologies suitable to their needs,whereas operations with lower production rates do not implement the currently available digital technologies to the same *** minor producers may require other digital transformation solutions tailored to their capabilities and needs and applicable to their scale of operations.

关键词： Diffusion of digital technologies Automation Internet of things Big data Machine learning Artificial intelligence

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

PICTORIAL ELEMENTS ***?“READINg”gESTURES IN COMEDY-RELATED VASE-PAINTINgS(4TH CENTURY BC)

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Journal of Ancient Civilizations 2021年第2期36卷 201-233,300页

作者： Elisabeth günther Classical Archaeology University of Trier

This paper examines the meanings and functions of gestures in comedy-related vase-paintings produced in southern Italy and Sicily during the 4th century *** discusses to what extent the gestures depicted in these images convey a specific meaning,and to what extent their“reading”depends on the composition as a whole,i.e.,the choice,positioning,and cognitive framework of the pictorial elements such as figures and objects.A first group of gestures indicates communication processes in“conversational”scenes usually with two *** these scenes,the meaning of gestures is of low importance,but their relative position within the composition displays which conversation partner dominates the other,often by inverting social *** second group consists of more specific gestures that express strong and often negative *** originate from tragedy-related vase-paintings,and this incongruence between tragic gesture and comic context causes a comic *** general,gestures are just one part of the cognitive framework of comedy-related vase-paintings which refer to comedy;however,they create a complex network of cognitive frames and thus evoke independent comic narratives.

关键词： partner READ frames

ROMAN LAW: OPENINg THE SYSTEM

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Journal of Ancient Civilizations 2018年第2期33卷 267-282,284页

作者： Sven günther IHAC NENU Changchun

Throughout the 20th century, Roman Law was mainly an enigma for historians and classical philologists alike. Its position in the Faculties of Law as Legal History and a systematic, and sometimes even synchronic, perspective of many researchers on legal sources together with self-referential tendencies made it appear a closed system, even though the nestor of Altertumswissenschaften, Theodor Mommsen had once encompassed the trias history, law and philology, albeit with his own taxonomy and connected with his liberal ideas that can be frequently found in his Romische geschichte and Romisches Staatsrecht.

关键词： ROMAN LAW OPENINg THE SYSTEM classical philologists