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Effect of ambient oxygen pressure on structural, optical and electrical properties of SnO_2 thin films

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Rare Metals 2006年第6期25卷 693-696页

作者： ZHAO Songqing ZHOU Yueliang WANG Shufang ZHAO Kun HAN Peng beijing National laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China Department of Mathematics and physics China University of Petroleum Beijing 102249 China

PolycrystaUine SnO2 thin films were deposited on sapphire substrates at 450℃ under different ambient oxygen pressures by pulsed laser deposition technique. The effect of ambient oxygen pressure on the structural, optical and electrical properties of SnO2 thin films was studied. X-my diffraction and Hall measurements show that increasing the ambient oxygen pressure can improve crystallization of the films and decrease resistivity of the films. A violet emission peak centered at 409 nm was observed from photoluminescence measurements for SnO2 films under deposition ambient oxygen pressure above 5 Pa, which is related to the improvement of crystalline of the films.

关键词： tin oxide pulsed laser deposition oxygen pressure PLD resistivity

Conductance and dielectric properties of pure C_(60) single crystal

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chinese Science Bulletin 1997年第1期42卷 40-43页

作者： YANG Guoquan, WANG Gang, WEN Weijia, ZHOU Weiya, LU Kunquan and XIE Sisheng1. Central University for Nationalities, beijing 100081, china 2. institute of physics, chinese academy of Sciences, beijing 100080, china Central University for Nationalities Beijing China institute of physics Chinese Academy of Sciences Beijing China

THE C60 is the third stable allotrope of carbon. Much attention has been focused on C60 since it has unique properties. Much work has been carried out on it, such as the preparation of large quantities of C60, the structure studies of C60, the superconducting alkali-metal-C60 compounds, the growth of pure C60 single crystal. There is still a lot of work to do in detail, but because the size of the single ctystal is not large enough, there is some difficulty in research, for example, the electric and optical properties of the C60 single crystal.

关键词： C60 single crystal vapor phase growth conductance dielectric properties.

Investigation of a New Exsolved Cu-Fe-S Phase in“Abnormal Sphalerite”

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 27-36,110-111页

作者： Li Jiuling Wang Su institute of Mineral Deposits, chinese academy of Geolgical Sciences,beijing beijing laboratory of Electron Microscopy, chinese academy of Sciences, beijing institute of Mineral Deposits Chinese Academy of Geolgical Sciences Beijing China

A new exsolved copper-iron-sulfur phase in sphalerite has been found in the Dajing cassiterite- sulfidecopper-silver-tin deposit, Inner Mongolia, china. After investigating the optical properties, chemical composi-tion, crystal structure and exsolved Characters of the exsolved phase, the authors present important evidencefor its being a new exsolved copper-iron-sulfur phase mineral. Its formation mechenism is discussed in consider-ing heating experiments, phase equilibrium data and the geology of the deposit.

关键词： Ph Fe Abnormal Sphalerite Cu

对超短脉冲激光与固体密度等离子体相互作用动力学过程的研究

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物理学报 2001年第9期50卷 1742-1746页

作者：苍宇王薇张杰中国科学院物理研究所光物理实验室首都师范大学物理系北京100037

结合Saha方程 ,建立了一个超短脉冲激光与固体密度等离子体相互作用的动力学过程中电子温度和电子密度随时间变化的简单模型 .在降温过程中采用绝热膨胀模型 ,讨论了等离子体在绝热膨胀过程中的特殊性质 ,考虑了离子声速随温度的变化 ,... 详细信息

结合Saha方程 ,建立了一个超短脉冲激光与固体密度等离子体相互作用的动力学过程中电子温度和电子密度随时间变化的简单模型 .在降温过程中采用绝热膨胀模型 ,讨论了等离子体在绝热膨胀过程中的特殊性质 ,考虑了离子声速随温度的变化 ,推算了状态演化过程 ,得到了电离度随时间变化的演化规律 .

关键词：超短超强脉冲激光固体密度等离子体电离度动力学过程离子声速 Saha方程电子温度电子密度绝热膨胀

2MASS photometry and age estimation of the globular clusters in the outer halo of M31

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Research in Astronomy and Astrophysics 2012年第2期12卷 115-126页

作者： Jun Ma 1,21 National Astronomical Observatories,chinese academy of Sciences,beijing 100012,china 2 Key laboratory of optical Astronomy,National Astronomical Observatories,chinese academy of Sciences,beijing 100012,china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Key laboratory of optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

We present the first photometric results in J, H and Ks from 2MASS （Two Micron All Sky Survey） imaging of 10 classical globular clusters （GCs） in the far outer regions of M31. Combined with the V and I photometric data from previous literature, we constructed a color-color diagram between J - Ks and V - Ⅰ. By comparing the integrated photometric measurements with evolutionary models, we estimate the ages of these clusters. The results showed that all of these clusters are older than 3 × 109 yr, and among them four are older than 10 Gyr and the other six have intermediate ages between 3 - 8 Gyr. The masses for these outer-halo GCs are from 7.0 × 104 M to 1.02 × 10^6 M. We argued that GC2 and GC3, whose ages, metallicities and distance moduli are almost the same, were accreted from the same satellite galaxy, if they did not form in situ. The statistical results show that the ages and metallicities of these 10 M31 outer-halo GCs do not vary with projected radial position, and a relationship between age and metallicity does not exist.

关键词： galaxies: halos - galaxies: individual (M31) - star clusters: general

Generation of surface electrons in femtosecond laser-solid interactions

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Science china(physics,Mechanics & Astronomy) 2006年第3期49卷 335-340页

作者： XU Miaohua1, LI Yutong1, YUAN Xiaohui1,2, ZHENG Zhiyuan1, LIANG Wenxi1, YU Quanzhi1, ZHANG Yi1, WANG Zhaohua1, WEI Zhiyi1 & ZHANG Jie1 1. Key laboratory of optical physics, institute of physics, chinese academy of Sciences, beijing 100080, china 2. State Key laboratory of Transient Optics Technology, chinese academy of Sciences, Xi’an 710068, china Key laboratory of optical physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China State Key laboratory of Transient Optics Technology Chinese Academy of Sciences Xi’an 710068 China

The characteristics of hot electrons produced by p-polarized femtosecond laser-solid interactions are studied. The experimental results show that the outgoing electrons are mainly emitted in three directions: along the target surface, the normal direction and the laser backward direction. The electrons flowing along the target surface are due to the confinement of the electrostatic field and the surface magnetic field, while the electrons in the normal direction due to the resonant absorption.

关键词： hot electrons,surface magnetic field,femtosecond laser pulses

Wet-chemical synthesis and characteristics of Au nanoshell

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Science china Chemistry 2005年第5期48卷 431-435页

作者： LIU Zhongxin1,2, SONG Hongwei1, YU Lixin1,2, YANG Linmei1,2 & PAN Guohui1,2 1. Key laboratory of Excited State physics, Changchun institute of Optics, Fine Mechanics and physics, chinese academy of Sciences, Changchun 130033, china 2. Graduate School of the chinese academy of Sciences, beijing 100039, china 1. Key laboratory of Excited State physics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130033 Changchun China 2. Graduate School of the chinese academy of Sciences 100039 Beijing China

Gold nanoshells were prepared by an easy wet-chemical method, with Ag nanoparticles used as the templates. Transmission electron microscopy (TEM) indicated that the shells were sphere in shape, the size was homogenous, being about 20 nm, and no hard ag-glomerates were observed. The plasma resonance absorption of gold was tuned from visible to near-infrared (NIR) with the increased volume of HAuCl4. The temperature grads (?T) of the gold nanoshell hydrosol under the exposure of an 808-nm optical fiber laser with different power den-sities were measured. The highest ?T was 30℃ (5 W/cm2, irradiation area was 2 cm2). This kind of gold nanoshell hydrosol is a promising material to be used in biomedicine such as photo-thermal cancer therapy, and its special photothermal convert property will photothermally trigger drug release.

关键词： wet-chemical synthesis, Au, nanoshell, NIR absorption, photothermal conversion.

The guanidine hydrochloride-induced denaturation of CP43 and CP47 studied by terahertz time-domain spectroscopy

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Science china(Life Sciences) 2007年第3期50卷 350-355页

作者： QU YuanGang1,3, CHEN Hua2, QIN XiaoChun1, WANG Li2, LI LiangBi1 & KUANG TingYun1 1 Key laboratory of Photosynthesis and Environmental Molecular Physiology, institute of Botany, chinese academy of Sciences, beijing 100093, china 2 laboratory of optical physics, institute of physics and Center for Condensed Matter physics, chinese academy of Sciences, beijing 100080, china 3 Graduate University of chinese academy of Sciences, beijing 100049, china 1. Key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China 3. Graduate University of chinese academy of Sciences Beijing 100049 China 2. laboratory of optical physics Institute of Physics and Center for Condensed Matter Physics Chinese Academy of Sciences Beijing 100080 China

Terahertz time-domain spectroscopy (THz-TDS) is a new technique in studying the conformational state of a molecule in recent years. In this work, we reported the first use of THz-TDS to examine the dena- turation of two photosynthesis membrane proteins: CP43 and CP47. THz-TDS was proven to be useful in discriminating the different conformational states of given proteins with similar structure and in monitoring the denaturation process of proteins. Upon treatment with guanidine hydrochloride (GuHCl), a 1.8 THz peak appeared for CP47 and free chlorophyll a (Chl a). This peak was deemed to originate from the interaction between Chl a and GuHCl molecules. The Chl a molecules in CP47 interacted with GuHCl more easily than those in CP43.

关键词： CP The guanidine hydrochloride-induced denaturation of CP43 and CP47 studied by terahertz time-domain spectroscopy THz time

Influence of Yb^(3+) concentration on the upconversion luminescence of oxyfluoride material doped with Er^(3+)

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Science china(physics,Mechanics & Astronomy) 2010年第2期53卷 310-314页

作者： ZHAO SuLing1,XU Zheng1,WANG LiHui2 & S. Wageh3 1 institute of Optoelectronic Technology,Key laboratory of Luminescence and optical Information (beijing Jiaotong University),Ministry of Education,beijing 100044,china 2 Department of physics,chinese People’s Public Security University,beijing 100038,china 3 physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University,Menouf 32952,Egypt 1. institute of Optoelectronic Technology Key Laboratory of Luminescence and Optical Information (Beijing Jiaotong University) Ministry of Education Beijing 100044 China2. Department of Physics Chinese People’s Public Security University Beijing 100038 China3. Physics & Engineering Mathematics Department Faculty of Electronic Engineering Menufiya University Menouf 32952 Egypt

In this paper,a new upconversion luminescent material co-doped with Erbium and Ytterbium is reported. The upconversion luminescence transition routes and related properties are studied. The results show that the absorption and emission intensities under excitation of 980 nm laser increase with the increase of the Yb3+ concentration. The red emission is stronger than the green emission. The energy transfer process plays an important role in the upconversion mechanism.

关键词： upconversion luminescence Er3+ Yb3+