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dy/Eu双掺杂CaLaGaO颜色可调荧光粉的制备与发光性能

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人工晶体学报 2024年

作者：刘云云黄传鑫王猛王燕枣庄学院光电工程学院中国科学院福建物质结构研究所

本文采用高温固相法成功制备了一系列Eu3+单掺和dy3+/Eu3+双掺CaLaGa3O7单基质荧光粉。通过X射线衍射和发射光谱对荧光粉的物相及发光性能进行了表征。结果表明，所制备的样品均为四方结构，与基质晶体一致，说明成功合成了Eu3+单掺和dy... 详细信息

本文采用高温固相法成功制备了一系列Eu3+单掺和dy3+/Eu3+双掺CaLaGa3O7单基质荧光粉。通过X射线衍射和发射光谱对荧光粉的物相及发光性能进行了表征。结果表明，所制备的样品均为四方结构，与基质晶体一致，说明成功合成了Eu3+单掺和dy3+/Eu3+双掺杂的CaLaGa3O7荧光粉。在波长393 nm近紫外光激发下，Eu3+：CaLaGa3O7表现出Eu3+的特征红光发射(5D0→7F2)，并且发光纯度高达100%。共掺dy3+之后，dy3+/Eu3+双掺CaLaGa3O7荧光粉不仅可以被波长393 nm的光激发还可以被波长348 nm的光激发。不管是哪个波长的光激发，dy3+/Eu3+：CaLaGa3O7发射光谱同时包含了Eu3+的特征红光发射和dy3+的特征黄光发射(4F9/2→6H13/2)。通过对发射谱和荧光寿命分析得出，双掺荧光粉中dy3+和Eu3+之间存在有效的能量传递过程。进一步计算了各个样品对应的色坐标，结果表明当激发波长由348 nm改变为393 nm时，色坐标整体上从黄绿色区域移动到黄橙光区域。因此，dy3+/Eu3+：CaLaGa3O7是一种光色可调发光材料，在显示和固态照明方面具有良好的应用前景。

关键词： CaLaGa O dy /Eu 双掺杂荧光粉发光性能颜色可调高温固相法

dy^(3+)-doped LiYF_4 crystals for UV-excited white light-emitting diodes

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Chinese Optics Letters 2013年第6期11卷 54-57页

作者：唐磊夏海平汪沛渊彭江涛江浩川 Key Laboratory of Photo-Electronic Materials Ningbo University Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences

A dy3＋-doped LiYF4 single crystal capable of generating white light by simultaneous blue and yellow light emission of phosphorescent centers is produced. Chromaticity coordinates and photoluminescence intensity vary with excitation wavelength. Under 350, 365, and 388 nm excitation, the crystal shows excellent white light emission. The most efficient wavelength for white light is 388 nm. The CIE *** are x=0.316 and y =0.321, and the color temperature （Tc） is 6 368 K. These results indicate that the studied crystal is a potential candidate for ultraviolet light-excited white light-emitting diodes.

关键词： dy doped LiYF4 crystals for UV-excited white light-emitting diodes LEDs UV

Microstructure and room temperature mechanical properties of NiAl-Cr(Mo)-(Hf,dy) hypoeutectic alloy prepared by injection casting

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Transactions of Nonferrous Metals Society of China 2013年第4期23卷 983-990页

作者：盛立远杨芳奚廷斐郑玉峰郭建亭北京大学深圳研究院深圳518057 北京大学工学院北京100871 深圳宝安国际机场深圳航空有限责任公司深圳518128 中国科学院金属研究所沈阳110016

The NiA1 Cr（Mo）（Hf, dy） hypoeutectic alloys were prepared by conventional casting and injection casting techniques respectively, and their microstructure and room temperature mechanical properties were investigated. The results reveal that with the addition of Hf and dy, the Ni2AIHf Heusler phase and Nisdy phase form along the NiAI/Cr（Mo） phase boundaries in intercellular region. By the injection casting method, some Ni2AIHf Heusler phase and Nisdy phase transform into Hf and dy solid solutions, respectively. Moreover, the microstructure of the alloy gets good optimization, which can be characterized by the fine interlamellar spacing, high proportion of eutectic cell area and homogeneously distributed fine Ni2AIHf, Nisdy, Hf solid solution and dy solid solutions. Compared with conventional-cast alloy, the room temperature mechanical properties of injection-cast alloy are improved obviously.

关键词： NiAI based hypoeutectic alloy Hf dy injection casting microstructure mechanical properties

Existence patterns of dy in β-NiAl from first-principles calculations

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Rare Metals 2016年第4期35卷 356-360页

作者： Tian Zhang Hong-Bo Guo Sheng-Kai Gong Hui-Bin Xu School of Materials Science and Engineering Beihang University

Intermetallic compound β-NiA1 is a promising material in high temperature applications due to its high melting temperature, high strength, low density, and good oxidation resistance. However, its application remains limited because of its relatively poor cyclic oxidation resistance. Addition of reactive element （RE） dy can improve the cyclic oxidation of NiA1 alloys significantly. However, the mechanism of dy addition is not clear. Even the existence pattern of dy in NiA1 is unspecified. Therefore, in the present study, the impurity formation energies of dy in stoichiometric NiA1, Ni-rich, and Al-rich NiA1 for the substitution cases were studied by first-principles density functional theory. The results show that dy could hardly substitute for either Ni or A1 atoms in NiA1. However, calculations for dissolution energies show that dy could be easily dissolved in AI vacancies in all three types of NiA1, which provides a new existence pattern of dy in NiA1 beyond experimental detection.

关键词： Existence pattern dy A1 vacancies First-principles

Magnetostriction Increase of Tb0.3dy0.7Fe1.95 Alloy Prepared by Solidification in High Magnetic Fields

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Chinese Physics Letters 2015年第3期32卷 137-140页

作者：王凯刘铁高鹏飞王强刘印赫冀成 Key Laboratory of Electromagnetic Processing of Materials of Ministry of Education Northeastern University

***1.95 alloys are solidified under various high magnetic field conditions. The influence of a high magnetic field on the crystal orientation, morphology and magnetostriction of the alloys are studied. The results show that with the increase of magnetic flux density, the crystal orientation of the （Tb,dy）Fe2 phase changed from （113） to （111） direction; the grains in the alloys tended to align along the magnetic field direction; and the magnetostriction of Tb0.3dy0.7Fe1.95 alloys is remarkably improved. The change in magnetostriction of ***1.95 alloys is linked to the amount and the crystal orientation behavior of the （Tb,dy）Fe2 phase.

关键词： dy Alloy Prepared by Solidification in High Magnetic Fields Magnetostriction Increase of Tb Fe

Magnetocrystalline Anisotropies of RFe_(10)V_2 (R=Y, Tb, dy, Ho, and Er) and Their Hydrides

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Journal of Materials Science & Technology 1998年第5期14卷 447-450页

作者： Weiren ZHAO Jueyun PING and Ruzhang MA (Material Physics Dept., University of Science and Technology Beijing, Beijing 100083, China)(Present address: Central Iron & Steel Research Institute,Beijing 100081, China) Material Physics Dept. University of Science and Technology Beijing Beijing 100083 China Central Iron and Steel Research Institute Beijing 100081 China

The magnetocrystalline anisotropies of RFe10V2 (R=Y, Tb, dy, Ho and Er) and their hydrides were studied by X-ray diffraction, magnetization and a.c. susceptibility measurements. The uniaxial anisotropy of Fe-sublattice and R-sublattice with positive second order Stevens αJ in RFe10V2 compounds is weakened by hydrogenation, while that of R-sublattice with negative αJ (Er) enhanced. Such a change of anisotropy causes planar-easy magnetic structures in RFe10V2 (R=Tb and dy) at room temperature and induces spin reorientation in HoFe10V2 after hydrogenation. The change of anisotropy of R-sublattice after hydrogenation may be owed to a decrease of the second order crystalline coefficient.

关键词： Ho and Er and Their Hydrides V2 R=Y dy Magnetocrystalline Anisotropies of RFe

In-situ dendrite reinforced dy-based amorphous matrix composites

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中国有色金属学会会刊：英文版 2009年第1期19卷 72-77页

作者：武晓峰赵威孟力凯 Faculty of Materials and Chemical Engineering Liaoning University of Technology

In-situ dendritic reinforced dy-Fe-Al amorphous matrix composites with a diameter of 3 mm were designed and fabricated by conventional Cu-mold casting method. XRD and SEM analyses were conducted to investigate the microstructure, the mechanical properties and the deformation and fracture behaviors of the composites. The forming mechanism and the deformation and fracture mechanism of the composites were discussed. The results indicate that the microstructures of composites consist of metallic glass matrix and α-dy dendritic phase. The composites exhibit good mechanical properties with compressive fracture strength of 1 063 MPa, which is attributed to the effective bearing-load ability of the α-dy dendrites and the glassy matrix and the restriction to the expanding of shear bands and cracks of the α-dy dendrites. The nature of in-situ crystalline phases embedded in the amorphous matrix for in-situ crystallite reinforced dy-Fe-Al amorphous matrix composites has a more important influence on the mechanical properties, the deformation and fracture behavior of the composites.

关键词： BMGs dy 强韧化机制金属学

Electroreduction of dy^(3+) on Ni Cathode in Molten Chlorides

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Journal of Rare Earths 1996年第4期14卷 271-274页

作者：童叶翔刘冠昆杨绮琴洪惠婵陈胜洋甘罗 Department of Chemistry Zhongshan University Guangzhou 510275 China

The cyclic voltammetry,electrode potential-time curve after potentiostatic electrolysis,potential-step method and X-ray diffraction were used to study the electrochemical reaction of dy￣(3+) in equimolar NaCl-KCl mixture on Ni *** dyNi5 forms at first and then the intermetallic compounds of dy-Ni containing more dy form in *** metallic dy deposits at *** dy-Ni alloy was prepared by consumable cathode in molten *** dy-Ni alloy contained dy over 85 wt% was *** composition of alloy was dyNi5 and *** current efficiency and the recovery of dy were near 80%.

关键词： Electroreduction dy-Ni alloy dy NaCl-KCl-dyCl_3

Shape Transition and Triaxial Interaction Effect in the Structure of ^(152-166)dy Isotopes

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Communications in Theoretical Physics 2014年第12期61卷 847-858页

作者： Falih H.Al-Khudair Abdul R.Subber Ashwaq F.Jaafer Physics Department Education College for Pure Sciences Basrah University

The positive parity states in even-even 152-166 dy are studied systematically in the framework of the interacting boson model(IBM). A cubic term, L = 3, has been added to the Hamiltonian in order to produce the effect of triaxiality on the energy spectrum. The potential energy surfaces as a function of β and γ deformation parameters,for all isotopes have been produced. Energy levels and reduced electric quadrupole transition probabilities are calculated in framework of IBM with Cubic term(IBMC). All results are compared with available experimental data. It is found that these isotopes can be described by a schematic Hamiltonian in transition from U(5)(vibration) to SU(3)(rotation)dynamic symmetry.

关键词： nuclear structure nuclear models dy isotopes