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Preparing Nano-ZnS by Solid State Reaction at Room Temperature

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Chinese Chemical Letters 2001年第2期12卷 187-188页

作者： Xiao Lin SUN guang yan hong Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied ChemistryChangchun 130022

ZnS nanoparticles were prepared by using solid-state reaction method at room temperature in agate mortar for the first time. The average particle size was about 20nm. This reaction is affected by the structure of reac... 详细信息

关键词： Zn nanoparticle solid-state reaction room temperature

Preparation and upconversion luminescence of YVO_4:Er^(3+),Yb^(3+)

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 225-228页

作者： Yong-ming Zhang yan-hong Li Peng Li guang-yan hong Ying-ning Yu School of Materials Science and Engineering Shenyang Institute of Chemical Technology Shenyang 110142 China Key Laboratory of Rare Earth Chemistry and Physics Chinese Academy of Sciences Changchun 130022 China

YVO4：Er^3＋,Yb^3＋ with varying Yb^3＋ concentrations were prepared by a precipitation *** results of X-ray diffraction （XRD） show that all the samples have a tetragonal zircon structure; the calculated average crystallite sizes are in the range of 14-22 *** lattice constants and cell volume of the samples decrease slightly with the increase in Yb^3＋ *** upconversion luminescence spectra of all the samples were studied under 980 nm laser *** strong green emission is observed,which is attributed to the 2^H11/2→4I15/2 and 4^S3/2→4^I15/2 transitions of Er^3＋,and the red emission peaks in 650-675 nm can be *** emission intensity for the sample depends on the Yb^3＋*** results reveal that the upconversion processes of YVO4：Er^3＋,Yb^3＋ are related to the structure and the doping Yb^3＋ concentration of the sample.

关键词： yttrium vanadate rare earth doped materials precipitation method upconversion luminescence

Preparation and characterization of gadolinium hydroxide single-crystalline nanorods by a hydrothermal process

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Chinese Chemical Letters 2007年第4期18卷 491-494页

作者： Yi Dong Yin guang yan hong Bai Fu Xin School of Chemistry ＆ Materials Science Heilongjiang University Harbin 150080 China Key Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

The Gd（OH）3 nanorods with diameters of ca. 40--60 nm and lengths of more than 400-550 nm have been prepared by a novel hydrothermal technique. The structural features and chemical composition of the nanorods were investigated by X-ray diffraction （XILD）, transmission electron microscopy （TEM）, and field emission scanning electron microscope （FESEM）, selected area electron diffraction （SAED）, and high resolution transmission electron microscopy （HRTEM）. The possible mechanism for the formation of Gd（OH）3 nanorods was proposed.

关键词： Gd(OH)3 Nanorods Hydrothermal method Lanthanide

Heat Flux Through Slag Film and Its Crystallization Behavior

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Journal of Iron and Steel Research International 2008年第4期15卷 7-11,20页

作者： TANG Ping XU Chu-shao WEN guang-hua ZHAO yan-hong QI Xin College of Materials Science and Engineering Chongqing University Chongqing 400044 China

An experimental apparatus for simulating copper mold is used to quantify the heat flux through the slag film and to obtain a solid slag for further determining its crystallization behavior. The result indicates that both the chemical composition of the mold powder and the cooling rate have an important influence on the heat flux through the slag film. With increasing the binary basicity, the heat flux of slag film decreases at first, reaches the minimum at the basicity of 1.4, and then increases, indicating that the maximum binary basicity is about 1.4 for selecting ＂mild cooling＂ mold powder. The heat transfer through the slag film can be specified in terms of the crystalline ratio and the thickness of the slag film. Recrystallization of the solid slag occurs and must be considered as an important factor that may influence the heat transfer through the solid slag layer.

关键词： continuous casting mold powder slag film heat flux crystallization

A New High Efficiency Green Luminescent Material──the System Al_2O_3-B_2O_3 Containing Ce^(3+) and Tb^(3+) Ions

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Chinese Chemical Letters 1998年第9期9卷 877-880页

作者： hong Peng YOU guang yan hong (Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences, Changchun 130022) Chinese Acad Sci Changchun Inst Appl Chem Lab Rare Earth Chem & Phys Changchun 130022 Peoples R China

To obtain high efficiency luminescent materials, the system Al2O3-B2O3 containing Ce3+ andTb3+ ions with variation of B2O3-content, has been prepared by Al2O3, H3BO3, CeO2 and Tb4O7 underreducing atmosphere at 1250i . It is notable that the brightness of the sample with appropriatecomposition is similar to that of commercial phosphorous containing Ce3+ and Tb3+, indicating that a newhigh efficency green luminescent material was obtained with appropriate B2O3-content.

关键词： the system Al_2O_3-B_2O_3 Ce^(3+) and Tb^(3+) ions a new high efficent green phosphorous

The Luminescence of The Phosphor Sr_2ZrO_4 with One-dimensional Chains Structure

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Chinese Chemical Letters 1999年第9期10卷 799-802页

作者： Lei ZHANG guang yan hong Xiao Lin SUN(1Changchun institute of Applied Chemistry. Chinese Academy of SciencesLaboratory of Rare Earth Chemistry and Physics. Changchun 1300222Institute of Modern Optics, Nankai University. Tianjin 300071) Chinese Acad Sci Changchun Inst Appl Chem Lab Rare Earth Chem & Phys Changchun 130022 Peoples R China Nankai Univ Inst Modern Opt Tianjin 300071 Peoples R China

A new type of phosphor Sr2ZrO4 with one-dimensional structure was prepared bysolid reaction and its luminescence is seen at room temperature. The excitation and emissionspectra were measured and display broad maximum ... 详细信息

关键词： Luminescence. zirconate one-dimensional structure.

Photochromism in CaS:Sm

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Chinese Chemical Letters 1999年第2期10卷 185-186页

作者： Xiao Lin SUN Gut Lan ZHANG Guo Qing TANG Wen Ju CHEN guang yan hong hong Peng YOU(Optical Information Science Laboratory, Institute of Modern Optics, Nankai University, Tianjin,300071)(Changchun Institute of Applied Chemistry, Chinese Academy of Scien Nankai Univ Inst Modern Opt Opt Informat Sci Lab Tianjin 300071 Peoples R China Chinese Acad Sci Changchun Inst Appl Chem Changchun 130022 Peoples R China

The photochromism in CaS:Sm (from white to pink) was observed for the first time by exposing it to ultraviolet light. The experiments results show that the absorption intensity of Sm2+ in the range of 500 similar to 600nm was strongly increased after irradiation. This reveals that there is the valence changing of Sm. If the sample was excited by visible light again, the pink color turned to white, indicating that CaS:Sm has potential application in the field of storage material.

关键词： Photochromism CaS : Sm valence transition storage material

Angiographic leakage of polypoidal choroidal vasculopathy on indocyanine angiography

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Chinese Medical Journal 2010年第12期123卷 1548-1552页

作者： ZUO Cheng-guo WEN Feng HUANG Shi-zhou LUO guang-wei yan hong WU Wei-ju WU De-zheng State Key Laboratory of Ophthalmology Zhongshan OphthalmicCenter Sun Yat-sen University Guangzhou Guangdong 510060China

Background There is no detailed report about the angiographic leakage of polypoidal choroidal vasculopathy （PGV） lesions on indocyanine green （ICG） angiography. This study aimed to investigate the angiographic leakage of polypoidal lesions in PCV on ICG angiography. Methods One hundred and forty-four eyes of 137 patients diagnosed as PCV were prospectively observed. Fundus examination, fluorescein angiography, and ICG angiography were performed. Leakage of polypoidal lesions and clinical features were recorded according to the angiograms. Results In all 144 eyes, 110 eyes showed angiographic leakage （leakage group） on ICG angiography and three subtypes of leakage group were noted, which were polypoidal dilations leakage （47 eyes, 42.7%）, branching vascular networks leakage （14 eyes, 12.7%） and leakage of both （49 eyes, 44.5%）. The other 34 eyes showed regression of polypoidal lesions （regression group）. In leakage group, the rates of pigment epithelial detachment （PED）, best corrected visual acuity （BCVA）〈0.1 and old subretinal hemorrhages were 56.4% （62 eyes）, 19.1% （21 eyes）, and 4.6% （5 eyes） respectively, compared with 8.8% （3 eyes）, 50% （17 eyes） and 38.2% （13 eyes） of regression group （P 〈0.001）. The history of regression group was significantly longer （P 〈0.001）. Conclusions Angiographic leakage and regression can be observed in PCV lesions. Leakage of both polypoidal dilations and branching vascular networks is the most common subtype in leakage group. PCV in leakage group is more likely to be related to PED, better BCVA and shorter history, while PCV regression group tends to relevant to old subretinal hemorrhage, worse BCVA and longer history. This may reflect that the former is active or in the early course while the later is resting or in the late phase of PCV.

关键词： classification indocyanine green angiography polypidal choroidal vasculopathy

基于信号相位匹配原理的目标方位估计的近场修正方法

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兵工学报 2009年第5期30卷 648-651页

作者：严光洪陈志菲孙进才西北工业大学航海学院陕西西安710072

分析了信号相位匹配(SPM)原理近场目标方位(DOA)估计精度低的原因,提出了基于信号相位匹配原理的近场目标高精度方位估计方法。仿真计算结果表明该方法具有指向性尖锐、高分辨、定向精度高和计算简单等特点。水池和外场试验进一步验证... 详细信息

分析了信号相位匹配(SPM)原理近场目标方位(DOA)估计精度低的原因,提出了基于信号相位匹配原理的近场目标高精度方位估计方法。仿真计算结果表明该方法具有指向性尖锐、高分辨、定向精度高和计算简单等特点。水池和外场试验进一步验证了该方法的正确性,该方法有效提高了近场目标信号波达方向估计精度。

关键词：信息处理技术方位估计近场信号相位匹配原理