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STRUCTURE OF Al-Mn-Zn-Mg ALLOY POWDER

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 79-84页

作者： WU Lijun ZHAO Lihua YANG Qiaoqin LI Shaolu LI Xieqian(materials Research and Test Centre,Hunan University,Changsha 410082.china)(Laboratory of Atomic Imaging of Solids,Institute of Metal Research,{2.,shenyang 110015,china)

The structure of Al-Mn-Zn-Mg alloy powder annealed at 800℃ has been studied by transmisston electron microscopy(TEM).An approximant phase(named as C-phase) to the decagonal phase was found and its crystal structure was determined It belongs to c-center orthorhombic lattice with a=2.35 nm,b=3.2. nm and c=1.2. *** stillfound a hexagonal phase with a=0.7) nm and c=0.79 nm,(named as phase) in the annealed alloy *** annealed alloy powder is composed of the C-phase,the phase,the decagonal phase and Al solid solution.

关键词： quasicrystal crystalline structure Al-Mn-Zn-Mg alloy powder

Stress Field of Non-equilibrium Grain Boundaries in Nano-crystalline Metals

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Journal of materials Science & Technology 2001年第3期17卷 388-388页

作者： Chiwei LUNG and Enke TIAN international Centre for materials {2., Institute of Metal Research, chinese academy of sciences, shenyang 110016, china Hengqiang YE Laboratory of Atomic Imaging of Solids, Institute of Metal Research, chinese academy of Sci chinese Acad Sci Met Res Inst Int Ctr Mat Phys Shenyang 110016 Peoples R China chinese Acad Sci Met Res Inst Atom Imaging Solids Lab Shenyang 110016 Peoples R China

Introducing the stress distribution near grain boundaries to improve the dislocation pileup model for the Halt-Petch (H-P) relation, the continuous distribution of dislocations in the pileup could be solved by means of Tschebysheff polynomials for the Hilbert transformation. An analytical formula of the stress intensity factor for the dislocation pileup is obtained. The reverse H-P relation may be explained by the modified dislocation-pileup-model.

关键词： Nano Stress Field of Non-equilibrium Grain Boundaries in Nano-crystalline Metals

Interannual variation of annual precipitation and urban effect on precipitation in the Beijing region

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Progress in Natural Science:materials international 2007年第9期17卷 1042-1050页

作者： Yu Shuqiu(State Key Laboratory on Severe Weather,chinese academy of Meteorological {2.,Beijing 100081,china) State Key Laboratory on Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081， China

The large scale character of the interannual variation of precipitation and the urban effect on local annual precipitation anomaly are investigated in this paper based on the 1960-2.00 annual precipitation observations at 2. stations in the Beijing *** results show that:the annual precipitation in the Beijing region possesses the large scale variation character with the linear trend of-1.197/10 yr,which corresponds to a total reduction of 2..82.mm in annual precipitation in the 41 years;the local annual precipitation anomalies(percent of the normal 1960-2.00)show a positive center near the urban area,*** precipitation island(UPI),whose intensity increases with the linear trend of 0.662.%/10 yr,opposite to the interannual trend of large scale precipitation over the Beijing region;changes in the UPI are also associated with the intensity of synoptic processes of precipitation,and when the synoptic processes are strong(wet years),the intensity of UPI strengthens,while the synoptic processes are weak(dry years),and the UPI disappears in the Beijing region.

关键词： urban precipitation island effect interannual climate variation precipitation Beijing atmospheric science

Glass formation of ternary Sm-based Sm-Al-Co bulk metallic glasses

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 50-53页

作者： Jiang Wu1), Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Chuang Dong1,2. 1) State Key Lab of materials Modification, Dalian University of Technology, Dalian 11602., china 2. {2. center of materials physics, chinese academy of sciences, shenyang, 110016, china

Ternary Sm-based Sm-Al-Co alloys at specific compositions designed using an e/a- and cluster-related criteria exhibit high glass forming abilities and form bulk glassy rods of 3 mm in diameter by a copper mold suction-casting method. Four composi- tions of bulk metallic glasses (BMGs) are Sm50Al2.Co2., Sm52.l2.Co2., Sm54Al2.Co2. and Sm56Al2.Co2., which all satisfy a constant conduction electron concentration of 1.5. Among them, the BMG exhibiting the largest reduced glass transition temperature (Trg) is Sm50Al2.Co2., which reaches 0.648. The glass transition temperature Tg and the onset crystallization temperature Tx of this alloy are respectively 579 and 640 K at a heating rate of 2. K/min.

关键词： Sm-based alloys bulk metallic glasses alloy design cluster line electron concentration

Cloud microphysical and rainfall responses to zonal perturbations of sea surface temperature:A cloud-resolving modeling study

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Progress in Natural Science:materials international 2009年第5期19卷 587-594页

作者： Xiaopeng Cuia, Xiaofan Lib, Zhiping Zongc a Laboratory of Cloud-Precipitation physics and Severe Storms (LACS), Institute of Atmospheric physics,{2., Beijing 10002., china b Joint center for Satellite Data Assimilation and NOAA/NESDIS/Office of Research and Applications, Camp Springs, MD, USA c National Meteorological center, china Meteorological Administration, Beijing 100081, china [a]Laboratory of Cloud-Precipitation physics and Severe Storms (LACS) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China [b]Joint Center for Satellite Data Assimilation and NOAA/NESDIS/Office of Research and Applications Camp Springs MD USA [c]National Meteorological Center China Meteorological Administration Beijing 100081 China

The cloud microphysical and rainfall responses to zonal perturbations of sea surface temperature (SST) are investigated by analyzing the equilibrium simulation data (from day 31-40) obtained from a series of two-dimensional cloud-resolving simulations with a zonal model domain of 768 km. Four experiments imposed by zonal SST perturbations of wavenumbers 1 (SST2.Z1), 2.(SST2.Z2., 4 (SST2.Z4), and 8 (SST2.Z8) are compared to the control experiment imposed by zonally uniform SST (SST2.). The model domain mean SST is 2. °C, and the two-dimensional cloud-resolving model with a cyclic lateral boundary is also imposed by zero vertical velocity and constant zonal wind. The time and model domain mean surface rain rates in SST2.Z1, SST2.Z2. and SST2.Z8 are about 10% larger than those in SST2., whereas the mean surface rain rates in SST2.Z4 and SST2. are similar. The analysis of mean surface rainfall budgets shows that local water vapor and hydrometeor changes play important roles in determining the differences and similarities in mean surface rain rate between the perturbation experiments and the control experiment. Both convective and stratiform rain rates are larger in SST2.Z1 and SST2.Z2.than in SST2. due to the smaller advection of rain from convective regions into raining stratiform regions and the larger vapor condensation rates associated with the larger water vapor convergence over raining stratiform regions in SST2.Z1 and SST2.Z2. The convective rain rates are larger in SST2.Z4 and SST2.Z8 than in SST2. because of the larger condensation rates associated with the larger water vapor convergence over convective regions in SST2.Z4 and SST2.Z8. The stratiform rain rates in SST2.Z4 and SST2.Z8 are smaller than in SST2. due to the smaller vapor condensation rates and smaller collection rates of cloud water by rain over raining stratiform regions in SST2.Z4 and SST2.Z8.

关键词： Cloud microphysical and rainfall responses Sea surface temperature Zonal perturbation Cloud-resolving modeling study

Cluster-based composition rules for ternary alloy systems

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international Journal of Minerals,Metallurgy and materials 2007年第S1期15卷 1-3页

作者： Chuang Dong1, 2., Qing Wang1), Weirong Chen1), Qingyu Zhang1), Jianbing Qiang1), and Yingmin Wang1) 1) State Key Laboratory of materials Modification, Dalian University of Technology, Dalian 11602., china {2., chinese academy of sciences, shenyang 110016, china

The cluster-based composition rule in ternary alloy systems including quasicrystals, bulk metallic glasses, crystalline phases and Lave phases-related body-centered cubic (BCC) solid solution forming systems was summarized. The so-called cluster line in a ternary phase diagram refers to a straight composition line linking a specific binary cluster to the third element. The compo- sition ranges of quasicrystals and bulk metallic glasses can be determined by the direct use of cluster lines, where two cluster lines intersect at the optimum phase forming composition. Furthermore, the alloys on the cluster line in Laves phase-related BCC solid solution alloy systems have larger hydrogen storage capacities.

关键词： cluster line composition design quasicrystals bulk metallic glasses hydrogen storage alloys

Studies of Structure Evolution of Nanostructured Hf_(11)Ni_(89) Alloy

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Journal of materials Science & Technology 1998年第3期14卷 205-210页

作者： Zhenfu DONG and Lianmao PENG(Beijing Lab. of Electron Microscopy, Institute of physics and center for Condensed Matter physics,chinese academy of sciences, P.O.Box 2.2., Beijing 100080, china)Ke LU and Zhuangqi HU(State Key Lab. for RSA, Institute of Meta Beijing Lab. of Electron Microscopy Institute of Physics and Center for Condensed Matter Physics Chinese Academy of Sciences P.O.Box 2724 Beijing 100080 China State Key Lab. for RSA Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

A nanostructured Hf11Ni89 ribbon sample was prepared by melt-spinning. It was found that the as-quenched sample is composed of a major HfNi5 compound nanophase and an interfacial magnetic Ni(Hf) solid solution phase. The structure evolution of the sample was studied by using X-ray difFraction (XRD), transmission electron microscopy (TEM), difFerential scanning calorimetry (DSC), resistivity and magnetothermal analysis. Upon heating, a second precipitation process of the Ni(Hf) phase prior to grain growth wa5 detected by means of both structural analysis and physical property measurements. The measurement results are discussed based on the relationship between microstructure and physical properties.

关键词： Studies of Structure Evolution of Nanostructured Hf Alloy Ni

Enhancement of magnetism of Zn0.95Co0.05O films by p-type Cu+ doping

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Progress in Natural Science:materials international 2011年第1期21卷 31-35页

作者： Wei-chang HAO~(1,5),Jian-jun LI~2.Huai-zhe XU~3,Jia-ou WANG~4,Tian-min WANG~1 1.center of materials {2. and Chemistry,Beihang University,Beijing 100083,china 2.Department of materials Science and Engineering, Anhui University of Science and Technology,Huainan 2.2.01,china 3.Department of {2.,Beihang University,Beijing 100083,china 4.Beijing Synchrotron Radiation Facility,Institute of High Energy {2., chinese academy of sciences,100049,china 5.Key Laboratory of Micro-nano Measurement,Manipulation and {2., Ministry of Education,Beihang University,Beijing 100191,china [a] center of materials {2. and Chemistry Beihang University Beijing 100083 China [b] Department of materials Science and Engineering Anhui University of Science and Technology Huainan 232001 China [c] Department of physics Beihang University Beijing 100083 China [d] Beijing Synchrotron Radiation Facility Institute of High Energy Physics Chinese Academy of Sciences 100049 China [e] Key Laboratory of Micro-nano Measurement Manipulation and Physics Ministry of Education Beihang University Beijing 100191 China

Zn0.95Co0.05O and Zn0.91Co0.05Cu0.04O thin films were fabricated on Si（111） substrate by the reactive magnetron sputtering method at different O-Ar *** characterizations by X-ray diffractometry（XRD）,X-ray photo-electronic spectrum（XPS）, and electron paramagnetic resonance（EPR） indicate that the doped Cu ions substitute the Zn2.ions in the ZnO *** doped Cu ions are in Cu+and Cu2.mixture valence *** ferromagnetism of the Zn0.91Co0.05Cu0.04O film increases gradually the increasing Cu+ions *** results indicate that the increase of ferromagnetism is not owing to the magnetic contribution of Cu+ions themselves,but owing to the enhancement of magnetic interaction between Co ions,which suggests that p-type doping of Cu+ions plays an important role in mediating the ferromagnetic coupling between Co ions.

关键词： Zn0.95Co0.05O films Zn0.91Co0.05Cu0.04O films magnetic semiconductors magnetic coupling co-doping

Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:materials international 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) Zhang Hongfu~2.Liu Xiaoming~3 Li Zhitong~4 (1.School of Earth and Space sciences,Peking University,Beijing 100871,china 2.Institute of Geology and Geo{2. and Key Laboratory of Mineral Resources,chinese academy of sciences,Beijing 10002.,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.Institute of Geology and Mineral Resources of shenyang,shenyang 110032.china) [a]School of Earth and Space sciences Peking University Beijing China [b]Laboratory of Mineral Resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]Institute of Geology and Mineral Resources of shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite