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Ammonium Ion Motion and Phase Transitions in(ND_(4))_(2)TeCl_(6) Studied by Raman Scattering

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Chinese Physics Letters 1996年第1期13卷 58-61页

作者： SHI Jin-rong MULLER S ARNSCHEIDT B PELZL J XU Yong-chen WU Xiang Pohl institute of Solid State Physics Tongji UniversityShanghai 200092 institute fur experimentalphysikⅲ AG Festkorperspektroskopiej Ruhr-UniversiBochum44780 BochumF.R.G.P.O.Box 102148 International Center for Materials Physics Academia SinicaShenyang 110015

The interna.1 vibrations of the ammonium ion in(ND_(4))_(2) TeCl_(6) have been studied by Raman scattering in the temperature range 4.2-300 *** tings of A_(1)-,E-,and T_(2)-modes have been o bserved at T_(c2)=48K and T_(c3)=28 *** split tings were well interpreted by group theoretical correlation *** reason for the transitions at T_(c2) and T_(c3) may be the decrease of the force constant in the deuterated ammonium ion.

关键词： Transition ammonium (4)

Relationship Between Oct agonal Quasicrystal and β-Mn Type Crystal in Cut Description

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Chinese Physics Letters 1996年第3期13卷 199-202页

作者： LI Fang-hua CHENG Yi-fan institute of Physics Chinese Academy of SciencesBeijing 1000801 Max-Planck-Institut fur Metallforschung Institut fur Werkstoff-WeissenschaftSeestrasse 9270147 StuttgartGermany

The transformation from the octagonal lattice to a square lattice is demonstrated straightforward under the cut description by introducing a peculiar linear phason *** calculated lattice parameter of the ft-Mn structure from the edge length of squares and rhombi forming the octagonal quasilattice is in agreement with experimental results.

关键词： strain. agonal lattice

Raman Scattering Study of ND_(4)^(+)-Ion Motion and Structural Phase Transitions in(ND_(4))_(2)PbCl_(6)

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Chinese Physics Letters 1996年第5期13卷 394-396页

作者： SHI Jin-rong XU Yong-chen Y.Kume B.Arnscheidt J.Pelzl WU Xiang Pohl institute of Solid State Physics Tongji UniversityShanghai 200092 Faculty of General Education Azabu UniversityFuchinobeSagatniharaKanagazva 229Japan Institut fur experimentalphysikⅢ AG Festkorperspektroskopie y Ruhr-Universitat Bochum44780 BochumGermany International Center for Materials Physics Chinese Academy of SciencesShenyany 110015

Rams spectra of the internal modes of ND^(+)_(4)-ion in (ND_(4))_(2)PbCl_(6) crystal have been recorded in the temperature range of 5-300 K.A new structural phase tratisition was observed at 34 K be-ca-use of deuterium *** behaviours of the internal modes of the ND 4-ion at this temperature show that the structural transition is one of first order.

关键词： effect. (4) Transition

Structural pavement assessment in Germany

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Frontiers of Structural and Civil Engineering 2018年第2期12卷 183-191页

作者： Lutz PINKOFSKY Dirk JANSEN Bundesanstalt fur Straflenwesen (Federal Highway Research institute) BASt Bruederstrasse 53 51427 Bergisch Gladbach Germany

The aging structure as well as the considerable increase of heavy-traffic load on Germany＇s motorways and trunk roads encourages the use of innovative, sound and reliable methods for the structural assessment on network level as well as on project level. Essential elements for this are data, which allow a reliable assessment. For a holistic approach to structural pavement assessment performance orientated measurements will be necessary. In combination with functional parameters as well as write-down models, strategically motivated decision making processes will be useful combined with technically motivated decision processes. For the application at the network level, the available methods for performance orientated measurements are still challenging, as they are based either on testing drill-cores or on non- traffic speed methods. In recent years significant innovation steps have been made to bring traffic speed bearing capacity measurements and methods for evaluating pavement structures on the road. The paper summarizes the actual assessment procedures in Germany as well as the ongoing work on the development and implementation of new methods and techniques.

关键词： pavement assessment Germany structure system

Synthesis and Characterization of Zinc Succinate, Zn(C4H4O4)

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Chemical Research in Chinese Universities 2001年第1期17卷 20-25页

作者： ZHENG Yue qing ** (institute for Solid State Chemistry, Ningbo University, Ningbo 315211, P. R. China) 宁波大学浙江宁波 315211 Max-Planck institute fur Festkor per forschung 德国 D-70569

PETERS Karl and von SCHNERING Hans Georg (Max Planck institute für Festkrperforschung, D 70569 Stuttgart, Germany)Zn(C 4H 4O 4) prepared by dissolving 0.483 g (1.41 mol) of Zn 3(OH) 4CO 3·H 2O and 0.5 g (4.23 mol) of C 4H 6O 4 in 50 mL of H 2O followed by slow evaporation at room temperature crystallizes in the monoclinic space group C 2 with the cell parameters a =0.757 9(1) nm, b =0.597 6(1) nm , c =0.626 5(1) nm, β =108.45(1)°, V =0.269 17(7) nm 3, D x=2.239 \{g/cm 3\}, Z =2 and the final R(F o)=0.039 and wR(F o 2)=0.088 for 396 reflections [ F o 2≥2 σ(F o 2)]. In the crystal structure unit, each Zn is tetrahedrally coordinated by four O atoms from four (C 4H 4O 4) 2- anions, each of which, in turn, bridges four Zn atoms to build up a 3D \{\} 3 ∞[Zn(C 4H 4O 4) 4/4 ] network. The thermal analyses indicate that Zn(C 4H 4O 4) is stable below 420 ℃.

关键词： Synthesis Zinc succinate Crystal structure Thermal decomposition

Drainage-induced ground response in a twin-tunnel system through analytical prediction over the seepage field

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Underground Space 2022年第3期7卷 408-418页

作者： Cheng-wei Zhu Wei Wu Hong-wei Ying Xiao-nan Gong Pan-pan Guo Research Center of Coastal and Urban Geotechnical Engineering HangzhouChina Institut fur Geotechnik Universitat fur BodenkulturFeistmantelstrasse 4A-1180 ViennaAustria institute of Geotechinical Engineering Hohai UniversityNanjingChina

Leakage-induced hydraulic and ground responses in a twin-tunnel system are analyzed via the proposed analytical solution on the seepage *** seepage continuity conditions are rigorously satisfied at the interface between the ground and the tunnel lining,in terms of both water pressure and seepage *** analytical solution is verified by comparing the results of numerical simulations.A detailed parametric analysis is carried out to explore the effect of tunnels’spatial layouts and degraded waterproof facilities on leakageinduced hydraulic and ground response,including head decline,water inflow and ground surface *** results show that the often used single tunnel model tends to overestimate the pore pressure on the lining along with water inflow into the tunnel,and underestimate the leakage-induced ground settlement.

关键词： Twin tunnel Leakage Head decline Water inflow Ground settlement

Characteristics in naturally and experimentally shocked chondrites: A clue to P-T conditions of impacted asteroids

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Science China Earth Sciences 2000年第5期43卷 480-486页

作者：谢先德陈鸣戴诚达 A.EI Goresy Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Max-Planck-institute fur Chemie Mainz 55128 Germany

The aim of this study is to compare the experimentally shock-induced features with those in naturally shocked chondrites and to test the feasibility of experimentally calibrating naturally induced features in shocked H- and L-chondrites. Samples of the Jilin chondrite (H5) were experimentally shock-loaded at the following peak pressures: 12, 27, 39, 53, 78, 83, 93 and 133 GPa respectively. Chondritic melts were first obtained at P>78 GPa and more than 60% melting was achieved at P^133 GPa. No high-pressure phases were observed in any of the shocked samples, neither in the deformed nor in the molten regions. Textural relations and mineral assemblages of the shocked samples are comparable to those encountered in the heavily shocked H-chondrite Yanzhuang but differ considerably from those found in heavily shocked L6 chondrites. Shock melt veins in L6 chondrites contain high-pressure polymorphs of olivine and pyroxene and high pressure liquidus phases. Scaling from shock experiments on millimeter-sized samples to natural shock features on kilometer-sized asteroids poses considerable problems in quantifying the P-T conditions during natural shock events on asteroids.

关键词： chondrite experiment shock characteristics asteroid P-T condition.

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ENVIRONMENTAL BEHAVIOR OF LINEAR ALKYLBENZENE SULFONATE (LAS) IN AQUATIC ECOSYSTEM

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Chinese Journal of Oceanology and Limnology 1991年第1期9卷 78-87页

作者：张甬元谭渝云 F.Korte institute of Hydrobiology Academia Sinica Wuhan 430072 Gesellschaft fur Strahlen-und Umweltforschung mbH Munchen Institut fur Ukokogische Chemie F.R. Germany

LAS degradation rate in Donghu Lake water under aerobic was much faster than under anaerobic condition . The half life of LAS in aerobic and anaerobic environment was 3.2 days and 57 days, respectively . The degradation rate at 25-27℃was approximately 20 times higher than that at 1.5-3.5℃.In a laboratory model aquatic ecosystem, two stages of bioconcentration in fish , daphnia and snail were observed . The first stage , on second day exposure , resulted from accumulation of intact LAS , and the second stage , on 16th day exposure , was due to metabolites . The bioconcentration factor (BCF) of LAS was extremely low in the muscle of hybrid carp (0.64), but rather high (2485) in the gall bladder .

关键词： anaerobic aquatic exposure degraded biodegradation digestion bladder intact extremely remove

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THE CHEMICAL COMPOSITIONS OF MINERALS IN QINGZHEN METEORITE AND ITS GEOCHEMISTRY SIGNIFICANCE

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Science China Chemistry 1989年第8期32卷 995-1002页

作者：侯渭欧阳自远 A.EL.GORESY H.YABUKI Guiyang institute of Geochemistry Academia Sinica Max-Planck institute fur Kernphysik Heidelberg West Germany institute of Physical and Chemical Research Japan

The chemical compositions of silicate minerals, sulphide minerals and metal Fe-Ni in theQingzhen meteorite were measured by the microprobe analyses. Based upon these chemicalcompositions, the cosmochemical behaviour and characteristics of the existing forms of themajor elements in the Qinzhen meteorite have been discussed. These characteristics show thatunder the S-rich, O-poor, and strongly reducing conditions, the light metal elements, such asCa, Mg, K, Na may form sulphide, and metal Fe-Ni may contain Si and P. However, we con-sider that the light metal-sulphide can be stable in the lower mantle and there are some Siand P in the Fe-Ni core. Finally, an earth core-mantle model is established, where the Fe-Ni core contains some Si and P; the lower mantle is composed of Mg-rich silicate, SiO_2 andsulphide; the upper mantle, of silicate and oxide.

关键词： enstatite chondrite Qingzhen meteorite earth core-mantle model

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