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The relationship between viscosity and glass forming ability of Al-(Ni)-Yb alloy systems

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Science china(Physics,Mechanics & Astronomy) 2010年第3期53卷 390-393页

作者： JIA Ran, BIAN XiuFang, Lü XiaoQian, SONG KaiKai & LI XueLian key laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), Shandong university, Jinan 250061, china 1. key laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Jinan 250061 China

The dynamic viscosity of Al-Yb and Al-Ni-Yb superheated melts was measured using a torsional oscillation viscometer. The results show that the temperature dependence of viscosity fits the Arrhenius law well and the fitting factors are calculated. The amorphous ribbons of these alloys were produced by the melt spinning technique and the thermal properties were characterized by using a differential scanning calorimetry (DSC). E (the activation energy for viscous flow), which reflects the change rate of viscosity, has a good negative relation with the GFA in both Al-Yb and Al-Ni-Yb systems. However, there is no direct relation between liquidus viscosity (ηL) and GFA. The superheated fragility M can predict GFA in Al-Yb or Al-Ni-Yb alloy system.

关键词： Al-based amorphous alloys glass-forming ability viscosity fragility of superheated melt

A tunable dual-narrowband band-pass filter using plasma quantum well structure

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Chinese Physics B 2014年第6期23卷 370-374页

作者：戴燚刘少斌王身云孔祥鲲陈忱 College of Electronic and Information Engineering Nanjing University of Aeronautics & Astronautics College of Electronic and Information Egineering Nanjing University of Information Science and Technology

A tunable dual-narrowband pass-band filter is designed. A one-dimensional photonic crystal （1D PC） is comprised of alternate dielectric layer and vacuum layer. Two quantum wells （QWs） as defects can be constructed by sandwiching two plasma slabs symmetrically in the 1D PC, and a dual-narrowband pass-band filter is formed. The conventional finite- difference time-domain （FDTD） method and piecewise linear current density recursive convolution （PLCDRC）-FDTD method are applied to the dielectric and plasma, respectively. The simulation results illustrate that the dual-narrowband frequencies can be tuned by changing the plasma frequency. The pass band interval and the half-power bandwidths （-3-dB band widths） are related to the space interval between two QWs.

关键词： quantum well dual-narrowband pass-band filter plasma

GRAIN REFINEMENT IN BULK HYPERCOOLED Ni_(50)Cu_(50) ALLOY

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 843-848页

作者： G.S. Song Z.Z. Zhang X.B. Dong, G.C. Yang and Y.H. Zhou(state key laboratory of Solidification Processing, Northwestern Polytechnical university, Xi’an 710072,china) Northwestern Polytechnical Univ Xi'an China

Undereooling eoperiments on binary Ni50 Cu50 alloy melts were conducted. The hypercooling limit of this alloy, which is about 310K, was evaluated by mcasuring plateau time needed for the interkendritic liquid solidification and extmpolating this function to zero. This limit was exceeded first in the binary alloy undereooled by about *** effect of liquid undercooling on the respective microstructure evolution was studied by optical metallogrnphy. The hypercooled microstructure contains rcsidual fragments within grain boundaries and is quite different from those obtained at undercoolings below 310K. The finding indicated the existence of dendrite break up. The dendrite break up may be induced either by remelting or by stress. By considering hyperrooling conditions and comparing two grain ndnement microstructures observed at small and larpe undereoolings, the forms of dendrite break up and the grain refinement mechanism exceeding the hypereooling limit are further discussed.

关键词： hypercooling grain refinement dendrite break up Ni_(50)Cu_(50) alloy

Relative importance of water, energy, and heterogeneity in determining regional pteridophyte and seed plant richness in china

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Journal of Systematics and Evolution 2011年第2期49卷 95-107页

作者： 1,2,3 Sheng-Bin CHEN § 1 Gao-Ming JIANG 3 Zhi-Yun OUYANG 3 Wei-Hua XU 3 Yi XIAO 1 (state key laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, china) 2 (Graduate university of the Chinese Academy of Sciences, Beijing 100049, china) 3 (state key laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, china) (state key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate university of the Chinese Academy of Sciences Beijing 100049 China) (state key laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China) *Correspondence: Gao-Ming JIANG *Correspondence: Sheng-Bin CHEN *Correspondence: ?Author for correspondence. E-mail: jianggm@*** Tel.: 86-10-62836506 Fax: 86-10-82596146.

Environmental variables, such as ambient energy, water availability, and environmental heterogeneity have been frequently proposed to account for species diversity gradients. How taxon-specific functional traits define large-scale richness gradients is a fundamental issue in understanding spatial patterns of species diversity, but has not been well documented. Using a large dataset on the regional flora from china, we examine the contrast spatial patterns and environmental determinants between pteridophytes and seed plants which differ in dispersal capacity and environmental requirements. Pteridophyte richness shows more pronounced spatial variation and stronger environmental associations than seed plant richness. Water availability generally accounts for more spatial variance in species richness of pteridophytes and seed plants than energy and heterogeneity do, especially for pteridophytes which have high dependence on moist and shady environments. Thus, pteridophyte richness is disproportionally affected by water-related variables; this in turn results in a higher proportion of pteridophytes in regional vascular plant floras (pteridophyte proportion) in wet regions. Most of the variance in seed plant richness, pteridophyte richness, and pteridophyte proportion explained by energy is included in variation that water and heterogeneity account for, indicating the redundancy of energy in the study extent. However, heterogeneity is more important for determining seed plant distributions. Pteridophyte and seed plant richness is strongly correlated, even after the environmental effects have been removed, implying functional linkages between them. Our study highlights the importance of incorporating biological traits of different taxonomic groups into the studies of macroecology and global change biology.

关键词： habitat heterogeneity pteridophytes seed plants species richness water-energy hypothesis.

A high-throughput model for screening anti-tumor agents capable of promoting polymerization of tubulin in vitro

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Acta Pharmacologica Sinica 2004年第6期25卷 73-80页

作者： Wei HU, Hui DONG, Yue-zhong LI2, Xi-tao HU, Guan-jun HAN, Yin-bo QU state keylaboratory of Microbial Technology, School of Life Science, Shandong university, Ji-nan 250100, china state key laboratory of Microbial Technology School of Life Science Shandong University Ji-nan 250100 China

AIM: To establish a high-throughput model for screening anti-tumor agents capable of promoting the polymeriza- tion of tubulin in vitro. METHODS: Tubulin was prepared in different purity for two screening steps. The first step was a high-throughput screening (HTS) for a set of 1500 samples using the GTP-containing tubulin and the end-reading method. The second step was performed on 119 hits from the first screening by a kinetic assay with GTP-lacking tubulin. RESULTS: The HTS for 1500 samples was accomplished in less than 3 h. From the screening, 108 samples were identified with >20 % promotion activity at 10 mg/L. Five of 108 were further confirmed by the kinetic assay using the purified tubulin subsequently. Three of the hit compounds were Epothilone A or its analogs, the other two compounds had new structures with a common pharmacophore for cytotoxic natural products that stabilize microtubules. In an MTT test, the five selected samples from the screening showed a minimal IC50 at0.28±0.06 nmol/Lto Helacells. CONCLUTION: The two-stepscreening methodis a high-throughtput, cost-effective, and efficient approach to identify microtubule-stabilizing agents.

关键词： antitumor drug screening assays tubulin polymerization promotor microtubules

Analytical layer-element solutions for a multi-layered transversely isotropic elastic medium subjected to axisymmetric loading

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Journal of Zhejiang university-Science A(Applied Physics & Engineering) 2012年第1期13卷 9-17页

作者： Zhi-yong AI Nai-rui CANG Jie HAN key laboratory of Geotechnical and Underground Engineering of MOE Department of Geotechnical Engineering Tongji University Shanghai 200092 China Department of Ciwl Environmental and Architectural Engineering The University of Kansas Lawrence KS 66045 USA

This paper presents an analytical layer-element method used to analyze the displacement of a multi-layered transversely isotropic elastic medium of arbitrary depth subjected to axisymmetric *** on the basic constitutive equations and the HU Hai-chang's solutions for transversely isotropic elastic media,the state vectors of a multi-layered transversely isotropic medium were *** the state vectors,an analytical layer element for a single layer(i.e.,a symmetric and exact stiffness matrix) was acquired in the Hankel transformed domain,which not only simplified the calculation but also improved the numerical efficiency and stability due to the absence of positive exponential *** global stiffness matrix was obtained by assembling the interrelated layer elements based on the principle of the finite layer *** solving the algebraic equations of the global stiffness matrix which satisfy the boundary conditions,the solutions for multi-layered transversely isotropic media in the Hankel transformed domain were *** actual solutions of this problem in the physical domain were acquired by inverting the Hankel *** paper presents numerical examples to verify the proposed solutions and investigate the influence of the properties of the multi-layered medium on the load-displacement response.

关键词： Transverse isotropy Analytical layer element Multi-layered elastic medium Axisymmetric loading Hankel transform

Assessing a soft twin tunneling numerical model using field data

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Journal of Pharmaceutical Analysis 2009年第1期21卷 36-41页

作者： Ke-shuan Ma1,2,Lie-yun Ding11. School of Civil Engineering and Mechanics,Hubei key laboratory of Control Structure, Huazhong university of Science & Technology, Wuhan 430074, china 2. Department of Civil Engineering, Nanyang Institute of Technology, Nanyang 473004, china. School of Civil Engineering and Mechanics Hubei Key Laboratory of Control Structure Huazhong University of Science and Technology Wuhan 430074 China Department of Civil Engineering Nanyang Institute of Technology Nanyang 473004 China

Using a five-floor building affected by the Yangtze River highway tunnels in Wuhan as the engineering background, we have constructed a free-field model and a coupled model to study the soil, lining, foundations and upper structure, and analyze the rules of movements of building foundation and ground induced by single tunnel and twin tunnel excavation with the Finite Element Analysis method. It is shown that for the coupled model, the longitudinal displacement of each foundation increases slowly when the tunnel face gets close to the foundation section and then increases fast when the tunnel face moves away from the foundation during the single and twin tunneling. For a single tunnel, the surface settlements are overestimated by the free-field and coupled tunnel. This might be crucial in urban areas. Regarding the maximum settlements and the width of the settlement trough, the difference between the free-field model and the coupled model is quite obvious. This comparison with the field measurement value reveals that the coupled model seems to be superior to the free-field model. These results are of instructive significance for design and excavation.

关键词： finite element analysis three-dimensional slurry shield tunneling building settlement

Synthesis　and　Crystal　Structure　of　a　New　Layered　Ternary　Tantalum　Telluride　TaNi_2Te_3

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Chinese Journal of Structural chemistry 1996年第4期15卷 318-322页

作者： Zhang Bin Wang Zhe-Min Liu Shi-Xiong Huang Jin-Ling(Department of chemistry , Fuzhou university, Fuzhou, 350002)(state key laboratory of Structural chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Department of chemistry Fuzhou University Fuzhou 350002 state key Lab. of Struct. chemistry Fujian Inst. Res. Struct. of Matter Chinese Academy of Sciences Fuzhou 350002

The title compound was synthesized by high temperature reaction of elements. TaNi_2Te_3, M_r= 681. 15, crystallizes in space group P2_1/m with dimensions a =7. 473(2), b=3. 708(1), c=10. 074(2) A, β=106. 78(2)°, V=267. 3(1) A￣3,Z= 2, D_c= 8. 46 g ·cm￣(-3), P=431. 43 cm￣(-1), F(000) = 570, T= 296K. The structure has been refined to final R = 0. 053 for 963 observations. This layered structure contains square-pyramidal Ta atoms and tetrahedral Ni atoms each coordinated by Te atoms. The layered structure may be considered as chain units ∞￣1[Ta_2Ni_2Te_6], which are linked by zigzag chains ∞￣1[Ni]. The title compound possesses a two-dimensional metal cluster. The structural relationship between this compound and its related compounds is discussed, and this is helpful for designing and synthesizing new layered compounds.

关键词： ternary tantalum telluride synthesis layered structure

Influence of the cobalt concentration on optical and magnetic properties of zinc oxide

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Chinese Science Bulletin 2010年第10期55卷 897-901页

作者： WANG LiWei,ZHANG FuJun,XU Zheng,ZHAO SuLing & LU LiFang Institute of Optoelectronics Technology,Beijing Jiaotong university key laboratory of Luminescence and Optical Information (Beijing Jiaotong university),Ministry of Education,Beijing 100044,china Institute of Optoelectronics Technology Beijing Jiaotong University Beijing China Ministry of Education Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Beijing China

A series of Co-doped ZnO thin films have been prepared by direct current reactive magnetron sputtering on glass *** structural characterization by means of X-ray diffraction (XRD) and scanning electron microscopy (SEM) gave no evidence of second phase *** qualitative composition and chemical state were characterized by energy dispersive X-ray spectroscopy (EDS) and X-ray photoelectronic spectrometry (XPS),*** results confirmed that Co was incorporated as Co3+,occupying the Zn2+ sites in ZnO's wurtzite *** luminescence properties of the films were investigated by room temperature photoluminescence,and the optical properties were studied by optical *** magnetic analysis was carried out at room temperature and at 50 K by Quantum Design MPMS (SQUID) *** results showed that all the Co-doped ZnO thin films prepared by direct current magnetron sputtering were not ferromagnetic above 50 K.

关键词：氧化锌钴氧化物磁性直流反应磁控溅射 X射线光电子能谱室温光致发光扫描电子显微镜纤锌矿结构