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study on growth and properties of novel γ-LiAlO_2 substrate

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science china(Technological sciences) 2006年第2期49卷 188-193页

作者： ZOU Jun1,2, ZHOU shengming1, XU Jun1 & ZHANG Rong3.1. shanghai Institute of Optics and Fine Mechanics, Chinese Academy of sciences, shanghai 201800, china 2. Graduate school of Chinese Academy of sciences, Beijing 10003., china 3. Laboratory of solid state Microstructures and department of Physics,{3., nanjing 210093. china 1. shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate school of Chinese Academy of sciences Beijing 100039 China 3. Laboratory of solid state Microstructures and department of Physics Nanjing University Nanjing 210093 China

Transparent γ-LiAlO2 single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O2-atmosphere at 1100°C for 70 h became opaque and Li-poor phase (LiAl5O8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 3. arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O2-atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 196 nm absorption peak was caused by Li vacancies and the 73. nm peak was caused by O vacancies.

关键词： γ-LiAlO2 crystal, scanning electron micrograph (sEM), absorption spectra.

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On c-equivalence

science china Mathematics 2009年第12期52卷 2389-2396页

作者： LI Xia department of Mathematics,nanjing university,nanjing 210093.china 1. department of Mathematics Nanjing University Nanjing 210093 China

In this paper,we propose some c-equivalence specifically for autonomous Lagrangian systems and show how to construct connecting orbits in energy surface based on this c-equivalence.

关键词： c-equivalence autonomous Lagrangian systems connecting orbits 3.K14

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sr, Nd and O Isotopic studies on the Genesis of the Huashan Granite Complex

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Acta Geologica sinica(English Edition) 1990年第1期64卷 41-54页

作者： Zhu Jinchu Li Xiangdong shen Weizhou Wang Yinxi Yang Jiedong department of earth sciences, nanjing university, {3., Jiangsu department of Materials Analysis, nanjing university, {3., Jiangsu Jia Zhongpeng department of earth sciences Nanjing University Nanjing Jiangsu China

systematical sr, Nd and O isotopic studies were made on the Huashan granite complex in Guangxi. Incombination with the studies of geological, petrological and geochemical data, it is believed that the complexconsists of granites of three stages. with different geneses and different source materials. They are not the prod-ucts of differentiation and evolution of one single consanguineous magma. Granites of the 1st stage are of theIndosinian syntectic type or I type, also derived from a mixed mantle-crustal source. Those of the 2nd stage areof the early Yanshanian syntectic type or I type. also derived from a mixed mantle-crustal source, and those ofthe 3.d stage are of the late Yanshanian transformed type or s type. derived from a crustal source.

关键词： Nd and O Isotopic studies on the Genesis of the Huashan Granite Complex sr

Diophantine vectors in analytic submanifolds of Euclidean spaces

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science china Mathematics 2007年第9期50卷 1334-1338页

作者： Rong-mei CAO~(1+) Jian-gong YOU~2 1 College of science,nanjing university of Aeronautics and Astronautics,nanjing 210016,{3. 2 department of Mathematics,nanjing university,nanjing 210093.{3. 1. College of science Nanjing University of Aeronautics and Astronautics Nanjing 210016 China 2. department of Mathematics Nanjing University Nanjing 210093 China

Let $\mathcal{M}$ be an m-dimensional analytic manifold in ? n . In this paper, we prove that almost all vectors in $\mathcal{M}$ (in the sense of Lebesgue measure) are Diophantine if there exists one Diophantine vect... 详细信息

关键词： diophantine vector analytic submanifold 3.C05

Variational construction of unbounded orbits in Lagrangian systems

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science china Mathematics 2010年第3期53卷 617-624页

作者： CHENG Chong-Qing 1, & LI Xia 2 1 department of Mathematics, nanjing university, nanjing 210093. china 2 department of Mathematics, suzhou university of science and Technology, suzhou 215001, china 1. department of Mathematics Nanjing University Nanjing 210093 China2. Department of Mathematics Suzhou University of Science and Technology Suzhou 215001 China

We show the existence of unbounded orbits in perturbations of generic geodesic flow in T2 by a generic periodic potential. Different from previous work such as in Mather (1997), the initial values of the orbits obtain... 详细信息

关键词： positive definite Lagrangian variational method unbounded orbit

A New One-Pot synthesis of Macroheterocycles Using Mannich Reaction

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Chinese Chemical Letters 1997年第10期8卷 845-846页

作者： Min Min YANG Jin Qi ZHANG Zhen sHEN (department of Chemistry, nanjing university, nanjing {3. nanjing UNIV DEPT CHEMNANJING 210093PEOPLES R CHINA

Three N,N-heterylmethyl derivates of diaza-18-crown-6(I) are readily prepared by the reaction of (I) with paraformaldehyde and heterocyclic compounds in dry benzene.

关键词： A New One-Pot synthesis of Macroheterocycles Using Mannich Reaction

special magnetic phenomena in heavily doped La_(0.7-x)Dy_xsr_(0.3.MnO_3.system

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science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2 ,YAN GuoQing 1,3.,CAI ZhiRang 1 ,PI Li 2 ,ZHANG Bei 2 &TONG Wei 2 1 department of Physics,suzhou College,suzhou 23.000,china 2 structure Research Laboratory,university of science and Technology of china,Hefei 23.026,china 3.National Laboratory of solid state Microstructures,Physics department,nanjing university,nanjing 210093.china 1. department of Physics Suzhou College Suzhou 234000 China 2. structure Research Laboratory University of Science and Technology of China Hefei 230026 China 3. National Laboratory of solid state Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxsr0.3.nO3.0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Chronological and geochemical studies of granite and enclave in Baimashan pluton, Hunan, south china

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science china earth sciences 2007年第11期50卷 1606-1627页

作者： CHEN WeiFeng1, CHEN PeiRong1, HUANG HongYe2, DING Xing1,3.& sUN Tao1 1 state Key Laboratory of Mineral Deposit Research, department of earth sciences, nanjing university,{3. 2 Research Institute No.23., CNNC, Changsha 410011, china 3.Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 1. state Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing 210093 China 2. Research Institute No.23. CNNC Changsha 410011 China 3. Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Zircon LA-ICP-Ms U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (204.5±2.8 Ma-209.2±3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (203.2±4.5 Ma-205.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 221.4±4.0 Ma to 226.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3.10±20.6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87sr/86sr)i ratios, and old T2DM (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in sC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

关键词： granite,mafic microgranular enclave,zircon LA-ICP-Ms dating,lithogenesis,EC-AFC

strange stars: Can Their Crust Reach the Neutron Drip Density?

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Chinese Journal of Astronomy and Astrophysics 2003年第6期3卷 535-542页

作者： Hai Fu and Yong-Feng Huangdepartment of Astronomy, nanjing university, nanjing {3. department of Astronomy Nanjing University Nanjing 210093 China

The electrostatic potential of electrons near the surface of static strange stars at zero temperature is studied within the frame of the MIT bag model. We find that for QCD parameters within rather wide ranges, if the nuclear crust on the strange star is at a density leading to neutron drip, then the electrostatic potential will be insufficient to establish an outwardly directed electric field, which is crucial for the survival of such a crust. If a minimum gap width of 200 fm is brought in as a more stringent constraint, then our calculations will completely rule out the possibility of such crusts. Therefore, our results argue against the existence of neutron-drip crusts in nature.

关键词： dense matter - elementary particles - stars: neutron