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LONG TErM HISTOrY (DEXTrAL TO SINISTrAL AND DUCTILE TO BrITTLE) Of thE DAMXUNG—JIALI SHEAr ZONE IN SOUthErN TIBET

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地学前缘 2000年第S1期7卷 155-156页

作者： M. A. Edwards, L. ratschbacher, members of INDEPth field geology group(Asian Tectonics research Unit, institut für Geologie, technische Universitt bergakademie freiberg, Bernhard\|von\|Cotta Strasse 2, D\|09596 freiberg, Germany,E\|mail: edwards@geo

the Damxung—Jiali shear zone is a shear zone in Southern Tibet that trends W—E for>*** appears to have a varied history of both displacement sense and deformation *** have examined microscopic and field data (including fault plane populations) in the westernmost 40km of the shear zone (on the northern margin of the Damxung graben near to the route of the INDEPth II deep seismic line). the shear zone outcrops along the southern flank of an W—E trending chain of hills in which all valleys run N—S, providing a series of sections of exposure through the shear zone. the shear zone is 3～5km wide and has varying degrees of deformation. It cuts across the main trends of, and does not seem to be restricted to any particular lithology. the principal fabric in the shear zone is steeply to moderately south dipping. the bulk of the shear zone is phyllite and lower grade schist with a consistent degree of both ductile and brittle strain. A mylonitized carbonate unit that is sometimes present within the phyllites may have locally provided a mechanical instability as indicated by the higher strain. Elsewhere a conglomerate unit contains carbonate clasts that are stretched (prolate) up to 30∶*** most spectacular unit forms lozenges of quartzifeldspathic rich rock (several 100m wide & 2～5km long) whose microfabric indicates deformation mechanisms (e.g., wholesale grainsize reduction) that operated around 400～500℃; the highest grade of the deformation fabrics. the lozenges are remnant evidence of higher temperature strain (at higher strain rate?) that is preserved only in the quartzifeldspathic rock. they are interpreted to be mega\|scale boudins resulting from their strength contrast with the weaker phyllites and schists during later lower temperature deformation. All the presently preserved sense of shear indicators are observed to be left\|lateral, and bulk shortening directions resolved using slip data from fault plane populations are consistent with this sinistra

关键词： Southern Tibet Nyenqengtanghla Damxung— Jiali shear zone high strain

Isogeometric Collocation:A Mixed Displacement-Pressure Method for Nearly Incompressible Elasticity Dedicated to Professor Karl Stark Pister for his 95th birthday

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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1125-1150页

作者： S.Morganti f.fahrendorf L.De Lorenzis J.A.Evans T.J.r.Hughes A.reali Department of Electrical Computer and Biomedical EngineeringUniversita degli Studi di PaviaPavia27100Italy institute of Applied Mechanics Technische Universitat BraunschweigBraunschweig38106Germany Department of Mechanical and Process Engineering Zurich8092Switzerland Department of Aerospace Engineering Sciences University of Colorado BoulderColorado80309USA institute for Computational Engineering and Sciences The University of Texas at AustinTexas78712USA Department of Civil Engineering and Architecture Universita degli Studi di PaviaPavia27100Italy

We investigate primal and mixed u−p isogeometric collocation methods for application to nearly-incompressible isotropic *** primal method employs Navier’s equations in terms of the displacement unknowns,and the mixed method employs both displacement and pressure *** benchmarks for what might be considered acceptable accuracy,we employ constant-pressure Abaqus finite elements that are widely used in engineering *** a basis of comparisons,we present results for compressible *** the methods were completely satisfactory for the compressible ***,results for low-degree primal methods exhibited displacement locking and in general deteriorated in the nearly-incompressible *** results for the mixed methods behaved very well for two of the problems we studied,achieving levels of accuracy very similar to those for the compressible *** third problem,which we consider a“torture test”presented a more complex story for the mixed methods in the nearly-incompressible case.

关键词： Isogeometric analysis isogeometric collocation nearly-incompressible elasticity

Microstructuring of titanium surfaces with plasma-modified titanium particles by cold spraying

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Particuology 2019年第3期17卷 90-104页

作者： P. Breuninger f. Krull S. Buhl A. Binder r. Merz M. Kopnarski B. Sachweh S. Antonyuk technische Universitat Kaiserslautern Institute of Particle Process Engineering Kaiserslautern Germany BASfSE Ludwigshafen Germany IfOS GmbH Institute for Surface and Thin Film Analysis GmbH Kaiserslautern Germany

Although the deposition mechanisms of the cold spray process are well studied, few reports regarding the use of surface-modified particles exist. Herein, titanium particles 3-39 μm in size and with an angular shape were modified in a plasma-enhanced chemical vapor deposition process in Ar, Ar-C2H2, and N2 plasmas. After Ar-C2H2 and N2 treatments, the respective presence of TiC and TiN on the particle surface was confirmed via transmission electron microscopy and energy-dispersive X-ray, X-ray photoelectron, and raman spectroscopies. the powders were deposited on titanium substrates by cold spray experiments, where unmodified particles up to 10(xm in size exhibited a successful surface bon ding. this finding was described by an existing analytical model, whose parameters were achieved by computational fluid dynamics simulations taking the particle shape factor into account:. A good deposition of plasma-modified particles up to 30 μm in size was experimentally observed, exhibiting an upper size limit larger than that predicted by the model. Higher surface roughness values were found for plasmamodified particles, as determined by 3D scanning electron microscopy. the water contact angle indicated that argon treatment influenced the wettability. Tribological tests showed a decrease of the initial friction coefficient from 0.53 to 0.47 by microstructuring.

关键词： Chemical vapor deposition Cold spray Surface modification Computational fluid dynamics

Analysing the effect of stand density and site conditions on structure and growth of oak species using Nelder trials along an environmental gradient:experimental design,evaluation methods,and results

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forest Ecosystems 2015年第3期2卷 243-261页

作者： Enno Uhl Peter Biber Matthias Ulbricht Michael Heym Tamás Horváth ferenc Lakatos Janós Gál Leonhard Steinacker Giustino Tonon Maurizio Ventura Hans Pretzsch School of Life Sciences Weihenstephan Technische Universitaet Muenchen University of West Hungary Faculty of Forestry faculty of Science and Technology Freie Universitat Bozen

Background: Most current approaches in forest science and practice require information about structure and growth of individual trees rather than- or in addition to- sum and mean values of growth and yield at forest stand level as provided by classic experimental designs. By inventing the wheel design, Nelder provided the possibility to turn to the individual tree as basic information unit. Such trials provide valuable insights into the dependency of growth on stand density at particular ***: Here, we present an extension of the original design and evaluation by Nelder.(i) We established Nelder wheels along an environmental gradient through Europe in atlantic climate in Belgium and Germany, Mediterranean climate in Italy, continental climate in Hungary as well as on high land climate in Mexico. Such disjunct Nelder wheels along an environmental gradient can be regarded and analysed as a two-factor design with the factors of site condition and stand density.(ii) We present an advanced statistical approach to evaluate density dependent growth dynamics of trees planted in form of the Nelder design, which considers spatio-temporal autocorrelation.(iii)We prove the usefulness of the methods in improving ecological theory concerning density related productivity,trade-offs between facilitation and competition, and allometric relations between size ***: first evaluations based on remeasured Nelder wheels in oak(Quercus robur L.) show a size growth differentiation during the first observation period. In particular, height growth is accelerated under higher competition indicating facilitation effects. We detect furthermore a high variability in allometric ***: the proposed design, methods, and results are discussed regarding their impact on forest practice,model building, and ecological theory. We conclude that the extended Nelder approach is highly efficient in providing currently lacking individual tree level information.

关键词： facilitation Long-term trial Nelder Single tree analyses Space use efficiency Stress-gradient-hypothesis Tree allometry Quercus

塔吉克斯坦、中国和匈牙利黄土磁性增强的路径

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地质科学译丛 1998年第2期15卷 50-53页

作者： th.forster f.Heller 曲赞 institut fur Geophysik Eidgenossische Technische Hochschule ZurichZurichSwitzerland

对采自塔吉克斯坦、中国和匈牙利的139个黄土及古土壤样品的分析来看,在所有剖面里,饱和磁化强度和饱和剩磁都随低场磁化率呈线性增加。其磁性的增强主要是由亚铁磁性矿物含量增加所致。高场磁化率(k_h)的变化认为是由粘土矿物引起,因... 详细信息

对采自塔吉克斯坦、中国和匈牙利的139个黄土及古土壤样品的分析来看,在所有剖面里,饱和磁化强度和饱和剩磁都随低场磁化率呈线性增加。其磁性的增强主要是由亚铁磁性矿物含量增加所致。高场磁化率(k_h)的变化认为是由粘土矿物引起,因为高场磁化率(k_h)与直径小于2μm 的矿物颗粒含量呈线性相关。磁性增强的过程可用一个综合理论模型来解释,该理论模型是以两种矫顽磁力不变、磁性矿物成分不同的集合体为基础。这个模型与匈牙利样品的结果很近似,且与塔吉克斯坦和中国磁性较强的古土壤样品数据吻合较好。塔吉克斯坦黄土样品的理论计算值和实测值之间的偏差较大。3种成分模型改进了实测数据和综合计算值之间的吻合程度。塔吉克斯坦和中国黄土磁性增强与古土壤的磁性增强机理不同,且在古气候和磁化率之间的关系方面不像匈牙利黄土-古土壤层序那样清晰。

关键词：黄土古土壤磁性增强机理古气候

Numerical fEM-Studies of rubble Mound Breakwaters—A Comparison between Calculated and Measured Data

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Numerical FEM-Studies of Rubble Mound Breakwaters—A Compari...

Land-Use Impact and Nitrate Analysis to Validate DrASTIC Vulnerability Maps Using a GIS Platform of Pablillo river Basin, Linares, N.L., Mexico

the 4th International Conference on Computing in Civil and Building Engineering

作者： H.WIBBELEr th.HArTMANN U.MEISSNEr Sonderforschungsbereich 205 Coastal EngineeringUniversity HannoverGermany Sonderforschungsbereich 205 Coastal EngineeringUniversity HannoverGermany institutefor Informatics in Civil Engineering Technische Hochschule DarmstadtGermany

＜正＞the contribution reports about the recent development of finite element models and their application to *** numerical model derived simulates the time- dependent process of wave propagation in a rubble mound bre...

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International Journal of Geosciences 2014年第12期5卷 1468-1489页

作者： rené Alberto Dávila Pórcel Christoph Schüth Héctor De León-Gómez Andreas Hoppe rowen Lehné facultad de Ingeniería Civil Universidad Autónoma de Nuevo León México Av. Universidad S/N Cd. Universitaria San Nicolás de los Garza México institut fur Angewandte Geowissenschaften technische Universitat Darmstadt Schnittspahnstra&szlig e 9 Darmstadt Deutschland

Preventive management of groundwater resources and their protection against pollution is one of the major challenges of our society. Groundwater systems are related with the surficial processes like territorial administration that is one of the most important tasks into the human development, because it involves serious problems to define the spatial medium, the industrial site-selection and the land-use allocation. Land-use and anthropogenic distribution could be the origin of the emission of pollutants that constitutes a serious health risk in urban areas. Nitrate was used as a pollution indicator in the Pablillo river Basin (PrB), to know the evolution of groundwater quality between 1981 and 2009 using GIS platform linked to vulnerability maps of DrASTIC (Depth to the water table;net groundwater recharge;Aquifer type;Soil type;Topography;Impact of the vadose zone and hydraulic Conductivity of the saturated zone). the study area is centered on the Linares city;changes in aquifer vulnerability were assessed over time on two stages (2007 and 2001). In both cases, depth from surface to groundwater plays an important role by being the most dynamic variable over time. this study shows that the depth of water table is the key factor in the evaluation of groundwater vulnerability. the significance of land-use impact in contamination process called Index of Pollution risk (IPr) and nitrate distribution process in the aquifer system was used as anthropogenic indicator together with the IPr in order to associate the land-use, the aquifer-vulnerability and human-activities. the final map of IPr allows determining possible polluted zones verified by high nitrate contents over the aquifer system. Land-use proved to be an important parameter necessary to correct the vulnerability maps using the DrASTIC method. this assessment is valid for situations where a specific time is defined because six of seven parameters change their properties in a very long term. the IPr-map could be

关键词： Vulnerability Maps DrASTIC Land Use Nitrate GIS

High temperature characteristic of hydroxyapatite-titania

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中国有色金属学会会刊：英文版 2005年第S3期15卷 443-446页

作者：汪涛张文彦 D.r.Annett S.Sabine College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics Nanjing 210016 China institute of Ceramic Materials Technische Universitt Bergakademie Freiberg Freiberg 09596 Germany institute of Analytical Chemistry Technische Universitt Bergakademie Freiberg Freiberg 09596 Germany

In order to provide the kinetic mechanism for optimizing the quality of the hydroxyapatite （Ca 10（PO4）6-（OH）2, HA） coating on Ti-alloy orthopedic devices, the high temperature behavior of HA-titania （TiO2） composite specimen was investigated using XrD, fTIr and 31P MAS NMr methods. thermal treatment of HA-TiO2 mixture powders leads to dehydroxylate and decompound of HA as well as chemical reaction between the two materials. Evidence for the initiation of the dehydroxylation of hydroxyapatite was found at 700℃ in air. the decomposition product of β-tricalcium phosphate was proven at 900℃ in air. Additionally, the formation of CaTiO3, derived from the chemical reaction between HA and titania at 900℃, was confirmed.

关键词： hydroxyapatite fT-Ir spectroscopy NMr spectroscopy titania XrD

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细管放电产生软X射线激光的研究

清华大学学报（自然科学版） 1998年第9期38卷 5-9页

作者：王新新 L.Michel 清华大学电机工程与应用电子技术系

介绍了作者在德国达姆斯达特大学（ＴｅｃｈｎｉｓｈｃｅＨｏｃｈｓｃｈｕｌｅＤａｒｍｓｔａｄｔ）应用物理所进行细管放电产生软Ｘ射线激光研究得到的初步实验结果。该细管放电装置的储能仅为４０Ｊ（５０ｎＦ，４０ｋＶ），放电电流... 详细信息

介绍了作者在德国达姆斯达特大学（ＴｅｃｈｎｉｓｈｃｅＨｏｃｈｓｃｈｕｌｅＤａｒｍｓｔａｄｔ）应用物理所进行细管放电产生软Ｘ射线激光研究得到的初步实验结果。该细管放电装置的储能仅为４０Ｊ（５０ｎＦ，４０ｋＶ），放电电流３０ｋＡ，电流上升时间１２０ｎｓ。硼硅酸玻璃（ｐｙｒｅｘ）细管直径为２．５ｍｍ，长度为５ｍｍ。采用预电离氩气的充气细管放电工作方式，气压为１ｈＰａ。等离子体柱的径向压缩速度约为４．５×１０４ｍ／ｓ，它在电流最大时刻附近被箍缩成一根直径为３００μｍ均匀细长柱。所拍摄到的谱线主要来自氩的＋７价（ＡｒⅧ）离子，它说明该装置所产生的等离子体的温度及其对应的氩电离等级接近产生氩类氖离子（ＡｒⅨ）软Ｘ射线激光要求。

关键词：细管放电软X射线激光