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Photoluminescence and thermoluminescence properties of dysprosium doped zinc metaborate phosphors 被引量:4
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作者 李娟 张纯祥 +4 位作者 唐强 郝景权 张彦立 苏锵 王淑彬 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期203-206,共4页
Polycrystalline powder samples of dysprosium doped Zn(BO2)2 phosphors were prepared by solid state reaction in air at high temperature and characterized by X-ray powder diffraction. The IR, Photoluminescence (PL),... Polycrystalline powder samples of dysprosium doped Zn(BO2)2 phosphors were prepared by solid state reaction in air at high temperature and characterized by X-ray powder diffraction. The IR, Photoluminescence (PL), diffuse reflectance and three-dimensional (3D) thermoluminescence (TL) emission spectrum after 60^Co gamma ray irradiation were investigated. The characteristic 3D TL emission bands at about 425, 481 and 573 um with a main emission band of around 573 um were attributed to the host emission, 4^F9/2→6H15/2 and F9/2→6^H13/2 f-f transitions of Dy^3+ ions. No emission from Dy^2+ ions was observed in the measurement wavelength range. The TL-dose response of the Zn(BO2)2:Dy polycrystalline powder sample to gamma ray radiation in the range from 1 to 100 Gy at clinical dose levels was almost linear. The experimental results showed that Zn(BO2)2:Dy had potential use as the materials of gamma-ray thermoluminescence dosimeter (TLD) for clinical dosimetry. 展开更多
关键词 THERMOLUMINESCENCE dysprosium DOSIMETRY zinc metaborate GAMMA-RAY rare earths
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Preparation of Dysprosium Ferrite/Polyacrylamide Magnetic Composite Microsphere and Its Characterization 被引量:3
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作者 雄泽英博 王志峰 +3 位作者 周兰香 张红 李幼荣 张明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第3期262-265,共4页
Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure,... Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability. 展开更多
关键词 dysprosium ferrite POLYACRYLAMIDE composite microsphere magnetic polymer microsphere rare earths
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Effects of Dysprosium Oxide Doping on Microstructure and Properties of Barium Titanate Ceramic 被引量:2
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作者 蒲永平 任慧君 +1 位作者 陈维 陈寿田 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期442-445,共4页
Different amounts of dysprosium oxide were incorporated into barium titanate powders synthesized by hydrothermal method. Relations of substitution behaviors and lattice parameters with solid-solubility were studied. F... Different amounts of dysprosium oxide were incorporated into barium titanate powders synthesized by hydrothermal method. Relations of substitution behaviors and lattice parameters with solid-solubility were studied. Furthermore, the influences of dysprosium oxide doping fraction on grain size and dielectric properties of barium titanate ceramic, including dielectric constant and breakdown electric field strength , were investigated via scanning electron microscope, X-ray diffraction and electric property tester. The results show that dysprosium oxide can restrain abnormal grain growth during sintering and that fine-grained and high density of barium titanate ceramic can result in excellent dielectric properties. As mass fraction of dysprosium oxide is 0.6%, the lattice parameters of grain increase to the maximum because of the lowest vacancy concentration. The electric property parameters are cited as following: dielectric constant (25 ℃ ) reaches 4100, the change in relative dielectric constant with temperature is - 10% to 10% within the range of - 15 - 100 ℃, breakdown electric field strength (alternating current) achieves 3.2 kV·mm^-1, which can be used in manufacturing high voltage ceramic capacitors 展开更多
关键词 inorganic nonmetallic material dysprosium oxide doping microstructure and properties barium titanate ceramic rare earths
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A Novel (4,6)-Connected Net Based on Dysprosium Benzenedicarboxylate,[Dy(OAc)(BDC)]_n 被引量:2
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作者 张磊 李兆基 +2 位作者 覃业燕 程建开 姚元根 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第8期915-918,共4页
A new lanthanide coordination polymer, [Dy(OAc)(BDC)]n 1 (OAc = acetate, BDC = 1,4-benzenediacarboxylate), has been synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals th... A new lanthanide coordination polymer, [Dy(OAc)(BDC)]n 1 (OAc = acetate, BDC = 1,4-benzenediacarboxylate), has been synthesized under hydrothermal conditions. Single-crystal X-ray diffraction analysis reveals that complex 1 has infinite zigzag Dy-OAc chains, which are further connected by BDC to form a 3D metal-organic framework. According to topology analysis, this framework can be characterized as (4,6)-connected (3.4.54)(32.4.56.66) net that has never been reported before. Crystal structure for 1: space group Pbca, a = 13.314(3), b = 8.0269(18), c = 20.275(5)A, V= 2166.8(9)A3, C10H7O6Dy, Mr = 385.66, Z= 8, Dc = 2.364 g/cm^3, μ= 6.910 mm^-1, F(000) = 1448, the final R = 0.0181 and wR = 0.0520. 展开更多
关键词 dysprosium polymer 1 4-benzenediacarboxylate ACETATE topology
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Solvent extraction equilibrium of dysprosium(Ⅲ) from nitric acid solutions with 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester 被引量:1
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作者 HUANG Ying TANAKA Mikiya 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第4期707-711,共5页
In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present stu... In view of the importance of solvent extraction of rare earth metals with the acidic organophosphorous reagent,the development of a chemically based model applicable to high concentration is desired.In the present study,the equilibrium distribution of dysprosium(Ⅲ)between an aqueous nitric acid solution and 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (PC88A)was measured in the range of an initial aqueous dysprosium(Ⅲ)concentration from 1.0×10-3to 1.0×10-1kmol/m 3and PC88A concentration from 0.16 to 0.65 kmol/m3in Shellsol D70 as the diluent.The obtained data were analyzed using the chemically based model in order to correlate the equilibrium distribution ratios.In this model,dysprosium(Ⅲ)was assumed to be extracted with the PC88A dimer as a 1:3 complex,the activities were considered for the aqueous species,and the effective concentration of the PC88A dimer was calculated using Alstad's empirical equation.As a result,the apparent extraction equilibrium constant was determined to be 253(kmol·m- 3)-2with an excellent correlation between the experiment and calculation results in the wide range of the logarithm of the distribution ratio from-2 to 3.5.In conclusion,the methodology in this model would be effective for quantitative description of solvent extraction behavior of general rare earth elements as well as dysprosium. 展开更多
关键词 solvent extraction dysprosium 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester(PC88A) nitric acid EQUILIBRIUM
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Preparation, Crystal Structure and Thermal Decomposition Process of Dysprosium Benzoate Complex with 1,10-Phenanthroline 被引量:1
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作者 XU Su-Ling ZHANG Jian-Jun +2 位作者 REN Ning ZHANG Hai-Yan HU Rui-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第2期233-237,共5页
A dinuclear dysprosium(III) complex with benzoic acid and 1,10-phenanthroline, [Dy(BA)3phen]2 (BA = benzoate, PHEN = 1,10-phenanthroline) (C66H46Dy2NaO12, Mr = 1412.07) was synthesized and characterized by ele... A dinuclear dysprosium(III) complex with benzoic acid and 1,10-phenanthroline, [Dy(BA)3phen]2 (BA = benzoate, PHEN = 1,10-phenanthroline) (C66H46Dy2NaO12, Mr = 1412.07) was synthesized and characterized by elemental analysis, UV, IR, X-ray diffraction, molar conductance and TG-DTG techniques. It crystallizes in triclinic, space group P1 with a = 10.773(2), b = 11.933(3), c = 12.417(5) A, α= 105.226(3),β= 93.470(3), γ= 113.475(2)°, V= 1388.0(7), Z = 1, Dc = 1.689 g/cm3, μ(MoKa) = 2.742 mm-1 and F(000) = 698. R = 0.0210, wR = 0.0538. In the crystal, each Dy(III) ion is eight-coordinated by one bidentate chelating carboxylate group, four bidentate bridging carboxylate groups and one 1,10-phenanthroline molecule. The thermal decomposition process of [Dy(BA)3phen]2 has been determined by thermal analysis. 展开更多
关键词 benzoic acid crystal structure 1 10-PHENANTHROLINE dysprosium complex thermal analysis
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Adsorption of D113 Resin for Dysprosium(Ⅲ) 被引量:1
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作者 王惠君 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2007年第4期653-656,共4页
The adsorption behavior and mechanism of D ll 3 resin for Dy(lII) was investigated by using the method of resin adsorption. Experimental results show that the optimum medium pH of adsorption of D 113 resin for Dy^3-... The adsorption behavior and mechanism of D ll 3 resin for Dy(lII) was investigated by using the method of resin adsorption. Experimental results show that the optimum medium pH of adsorption of D 113 resin for Dy^3- is pH=6.00 in the HAc-NaAc medium. The static adsorption capacity of D113 resin for Dy3. is 292.7 mg·g^-1. The optimum eluant is 0.5 mol,L-~ HC1. The adsorption rate constant is k298=6.8× 10-6s^-1. The apparent activation energy of D113 resin for Dy(Ⅲ) is 14.79 kJ·mol^-1. The adsorption behavior of D113 resin for Dy(Ⅲ) obeys the Freundlich isotherm. The adsorption parameters of thermodynamic are AH=14.48 kJ·mol^-1,△S=54.69 J·mol^-1,K^-1, △G= 1.82 kJ·mol^-1.The adsorption mechanism of Dll3 resin for Dy^3- was confirmed by chemical analysis and IR spectra. 展开更多
关键词 Dll3 resin adsorption behavior adsorption mechanism dysprosium(Ⅲ) RARE-EARTHS
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Study on Synthesis and Polymerization of Mono (isopropylmaleate oyloxyl) Diisopropoxyl Dysprosium 被引量:1
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作者 刘文敏 汪联辉 +1 位作者 王家芳 章文贡 《Journal of Rare Earths》 SCIE EI CAS CSCD 2000年第2期97-99,共3页
Mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium(DM) was synthesized by the reaction of dysprosium isopropoxide with maleic anhydride. Dy-containing polymer(PDM) was obtained by the solution polymerization of ... Mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium(DM) was synthesized by the reaction of dysprosium isopropoxide with maleic anhydride. Dy-containing polymer(PDM) was obtained by the solution polymerization of DM using 2, 2'-azobisisobutyronitrile (AIBN) as an initiator. The kinetic study on the polymerization shows that the polymerization of DM exhibits high apparent activation energy(96.3 kJ.mol(-1)), indicating that the activity of DM is low for polymerization. The kinetic equation of polymerization can be expressed as R-P = k(P)C(DM)(1.23)c(AIBN)(0.82). The polymeric solid material shows excellent heat-stability and strong characteristic fluorescence of Dy3+, (4)Fg(9/2) --> H-6(15/2) and F-4(9/2) --> H-6(13/2). 展开更多
关键词 rare earths mono(isopropyl maleate-oyloxyl) diisopropoxyl dysprosium POLYMER
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The Electroreduction of Gadolinium and Dysprosium Ions in Equimolar NaCl-KCl Melt 被引量:1
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作者 Hasbi B. Kushkhov Aziza S. Uzdenova +2 位作者 Mahmoud M. A. Saleh Abdalkader M. F. Qahtan Lily A. Uzdenova 《American Journal of Analytical Chemistry》 2013年第6期39-46,共8页
The mechanism of rare earth metals (Gd and Dy) chloride complexes electroreduction on the tungsten electrode in equimolar NaCl-KCl melt at 973 K has been studied by linear and cyclic voltammetry. Some kinetic paramete... The mechanism of rare earth metals (Gd and Dy) chloride complexes electroreduction on the tungsten electrode in equimolar NaCl-KCl melt at 973 K has been studied by linear and cyclic voltammetry. Some kinetic parameters of processes were calculated. It was shown that the tungsten electrode was indifferent to gadolinium and dysprosium which were reduced on the surface. We found that the discharge mechanism of gadolinium and dysprosium chloride complexes was described by three-electron step when the steady-state conditions of polarization were limited by the mass transfer stage. The conditions of nonstationary polarization made the slowness of the charge transfer stage. The diffusion coefficient of gadolinium and dysprosium ions was calculated, the diffusion coefficient of GdCl3-6 ions was (0.9 ± 0.2) × 10-5 cm2.s-1, and for DYCI3-6 ions, it was (1.60 ± 0.2) × 10-5 сm2.s-1. 展开更多
关键词 MOLTEN Chlorides GADOLINIUM TRICHLORIDE dysprosium TRICHLORIDE The ELECTROREDUCTION Mechanism Tungsten Electrode Linear and Cyclic VOLTAMMETRY The Diffusion Coefficient
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Probing Structure, Thermochemistry, Electron Affinity and Magnetic Moment of Dysprosium-doped Silicon Clusters DySi_n(n = 3~10) and Their Anions with Double-hybrid Density Functional Theory 被引量:1
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作者 宁红梅 顾晏松 +1 位作者 程琳 杨桔材 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第6期854-870,共17页
The equilibrium geometries, electronic structures and electronic properties including adiabatic electron affinity(AEA), vertical detachment energy(VDE), simulated photoelectron spectroscopy, HOMO-LUMO gap, charge ... The equilibrium geometries, electronic structures and electronic properties including adiabatic electron affinity(AEA), vertical detachment energy(VDE), simulated photoelectron spectroscopy, HOMO-LUMO gap, charge transfer, and magnetic moment for DySi_n(n = 3~10) clusters and their anions were systematically investigated by using the ABCluster global search technique combined with the B3 LYP and B2 PLYP density functional methods. The results showed that the lowest energy structure of neutral DySi_n(n = 3~10) can be regarded as substituting a Si atom of the ground state structure of Si_(n+1) with a Dy atom. For anions, the extra electron effect on the structure is significant. Starting from n = 6, the lowest energy structures of DySi_n~?(n = 3~10) differ from those of neutral. The ground state is quintuplet electronic state for DySi_n(n = 3~10) excluding DySi_4 and DySi_9, which is a septet electronic state. For anions, the ground state is a sextuplet electronic state. The reliable AEA and VDE of DySi_n(n = 3~10) are reported. Analyses of HOMO-LUMO gaps indicated that doping Dy atom to silicon clusters can improve significantly their photochemical reactivity, especially for DySi_9. Analyses of NPA revealed that the 4 f electrons of Dy in DySi_4, DySi_9, and DySi_n~? with n = 4 and 6~10 participate in bonding. That is, DySi_nbelongs to the AB type. The 4 f electrons of Dy atom provide substantially the total magnetic moments for DySi_n and their anions. The dissociation energies of Ln(Ln = Pr, Sm, Eu, Gd, Ho, and Dy) fromLn Sin and their anions were evaluated to examine the relative stabilities. 展开更多
关键词 dysprosium-doped silicon clusters the ground state structure dissociation energy electronic property
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Synthesis and Crystal Structure of Tri-(2-mercaptopyridine N-oxide)bis(dimethyl sulfoxide) Dysprosium(III)
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作者 牛德仲 陈久桐 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期520-524,共5页
A range of rare earth metal complexes of 2-mercaptopyridine N-oxide (Hmpo) have been synthesized, and studied by elemental analysis and IR spectroscopic technique. Crystal structure of Dy(mpo)3(DMSO)2 (DMSO = dimethyl... A range of rare earth metal complexes of 2-mercaptopyridine N-oxide (Hmpo) have been synthesized, and studied by elemental analysis and IR spectroscopic technique. Crystal structure of Dy(mpo)3(DMSO)2 (DMSO = dimethyl sulfoxide) has been determined. The complex crystallizes in the triclinic system, space group P with lattice parameters: a = 9.602(3), b = 9.803(3), c = 15.498(5) ? a = 89.51(1), b = 85.73(1), g = 62.99(1)? Dc = 1.787 g/cm3, C19H24N3O5S5Dy, Mr = 697.21, Z = 2, F(000) = 690, = 3.321mm-1, the final R = 0.0237 and wR = 0.0587 for 4116 reflections with I > 2s(I). The coordination number of dysprosium (Ⅲ) is eight, and its coordination geometry is a somewhat distorted square antiprism with O(3), O(4), O(5), S(3) and O(1), O(2), S(1), S(2) at the tetragonal bases (dihedral angle between their mean planes is 2.9(1)). Around the Dy atom, three five-membered ring planes (Dy, O, N, C, S) make the dihedral angles of 74.42, 11.31 and 83.72, respectively. 展开更多
关键词 dysprosium GADOLINIUM NEODYMIUM 2-mercaptopyridine N-oxide
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Synthesis and Structure of Tetrahydrofuran Adduct of Tris(indenyl)dysprosium
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作者 周锡庚 黄小荥 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1999年第5期373-377,共5页
Reaction of DyCl 3 with excessive amount of K and indene in THF forms (C 9H 7) 3Dy(THF), which crystallizes in hexagonal system, space group P6 3 with a= b=11.719(5), c=10.167(2) , V=1211(1) 3, M r=580.0... Reaction of DyCl 3 with excessive amount of K and indene in THF forms (C 9H 7) 3Dy(THF), which crystallizes in hexagonal system, space group P6 3 with a= b=11.719(5), c=10.167(2) , V=1211(1) 3, M r=580.07, D c =1 590 g/cm 3, Z=2, F(000)=578, μ =31.31 cm -1 . Final R =0.043 and R w =0.055 for 1273 observed reflections with I>3σ(I ). The crystal structure shows that in the title compound the indenyl group is bonded to dysprosium in an η 3+η 2 fashion, and is bent over the C(1) and C(3) axis by 12.7°. Its nodal carbon atoms C(4) and C(9) which are weakly bonded to the metal atom are at distances of 2.92(1) and 2.94(1) , respectively. The average Dy-C( η 3) bond distance is 2.66(1) . 展开更多
关键词 dysprosium INDENYL organolanthanide crystal structure
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Synthesis of Tenoltrifluoroacetone Composite Doped with Terbium, Dysprosium and Europium Encapsulated in Silica Oxide Matrix
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作者 Yazmin Francisco Dulce Medina +4 位作者 Miguel Barron Joan Reyes Pedro Adrian Martinez Angel de Jesus Morales Elizabeth Garfias 《Journal of Surface Engineered Materials and Advanced Technology》 2020年第4期63-74,共12页
The synthesis of the thenoyltrifluoroacetone compound doped with terbium, dysprosium and europium encapsulated in a silica matrix (TTA:Tb:Dy:Eu@SiO<sub>2</sub>) were performed by the sol-gel method. The pr... The synthesis of the thenoyltrifluoroacetone compound doped with terbium, dysprosium and europium encapsulated in a silica matrix (TTA:Tb:Dy:Eu@SiO<sub>2</sub>) were performed by the sol-gel method. The precursors to obtain the vitreous phase (SiO<sub>2</sub>) were: Tetraethylorthosilicate (TEOS, C<sub>8</sub>H<sub>2</sub>O<sub>4</sub>Si, 98%, Aldrich), and ethyl alcohol (CH<sub>3</sub>CH<sub>2</sub>OH, 99.5%, Meyer), distilled water and 0.05 ml of hydrochloric acid (HCl, Meyer). The sample with molar ratio 20:80 TTA:Tb:Dy:Eu@SiO<sub>2</sub> has the best emission intensity. Thermogravimetric analysis (TGA) shown that silica encapsulated samples decompose at lower temperatures than pure TTA:Tb:Dy:Eu luminescent material. Fourier Transform Infrared (IR-TF) shown the characteristic Si-O-Si bands that are presented at a wavelength of 1049, 853 and 440 cm<sup><span style="color:#4F4F4F;font-family:-apple-system, "font-size:16px;white-space:normal;background-color:#FFFFFF;">&#45</span>1</sup> confirming that the luminescent material is encapsulated in a silica matrix, finally X-ray diffraction (XRD) shown that TTA:Tb:Dy:Eu@SiO2 composite is amorphous. 展开更多
关键词 Synthesis Luminescence COMPOSITE SOL-GEL TERBIUM dysprosium and Europium
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Dysprosium Modification of Cobalt Ferrite Ionic Magnetic Fluids
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作者 JIANG Rong-li LIU Yong-chao GENG Quan-rong ZHAO Wen-tao 《Journal of China University of Mining and Technology》 EI 2005年第4期354-356,共3页
Dysprosium composite cobalt ferrite ionic magnetic fluids were prepared by precipitation in the presence of Tri-sodium citrate. Influence of dysprosium modification on magnetic property is studied. The result shows th... Dysprosium composite cobalt ferrite ionic magnetic fluids were prepared by precipitation in the presence of Tri-sodium citrate. Influence of dysprosium modification on magnetic property is studied. The result shows that magnetic response toward exterior magnetic field can be improved by adding Dy3+. Studies also show that the increase of reaction temperature may improve the modification effect of dysprosium. By adding dysprosium ions, the average diameter of the magnetic nanoparticles will be decreased evidently. It is clear that the particles appear as balls. Cobalt ferrite with sizes of 12-15 nm, rare earth composite cobalt ferrite with sizes of 6-8 nm. 展开更多
关键词 cobalt ferrite magnetic fluids dysprosium modification mechanism magnetic property
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Ferromagnetic Calculation of Terbium Dysprosium and Holmium with Polyhedron Electron Shell
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作者 Zilong Kong 《Journal of Modern Physics》 2015年第13期1776-1780,共5页
Based on the regular polyhedron model of multi-electronic atom combined with the Bohr hypothesis, the following supposition is put forward: the electron momentum multiplied by the inscribed sphere radius of edges of e... Based on the regular polyhedron model of multi-electronic atom combined with the Bohr hypothesis, the following supposition is put forward: the electron momentum multiplied by the inscribed sphere radius of edges of each regular polyhedron is equal to the Planck constant. The relationship between saturation magnetization rates and Planck constants is determined, and the ferromagnetism of atoms is obtained from regular dodecahedron and regular hexahedron. Then, terbium, dysprosium, and holmium saturation magnetization rate are obtained from electronic regular polyhedron configuration. Derivation of matter wave formula is from thermodynamics, avoiding over speed of light. 展开更多
关键词 Atomic Structure Regular POLYHEDRON ELECTRON SHELL Ferromagnetism of TERBIUM dysprosium and HOLMIUM Matter Wave Formula
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STUDIES ON FLUORESCENCE SPECTRA OF SAMARIUM EUROPIUM TERBIUM AND DYSPROSIUM WITH BENZOYL UREA DERIVATIVES AND PHENANTHROLINE
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作者 Xin Zhen DU, Jin Zhang GAO, Qun XIE and Jing Wan KANG Institute of Chemistry, Northwest Normal University, Lanzhou 730070 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第11期989-992,共4页
Rare earth chelates of benzoyl urea derivatives were prepared in ethanol and fluorescence spectra of these chelates were studied in detail. A composition of [RE(BU)_3Phen] (NO_3)_3 was obtained. Correlation between ch... Rare earth chelates of benzoyl urea derivatives were prepared in ethanol and fluorescence spectra of these chelates were studied in detail. A composition of [RE(BU)_3Phen] (NO_3)_3 was obtained. Correlation between chemical properties of ligands, chelates and spectroscopy was discussed. Intramolecular energy transfer in rare earth chelates was explained. 展开更多
关键词 Eu STUDIES ON FLUORESCENCE SPECTRA OF SAMARIUM EUROPIUM TERBIUM AND dysprosium WITH BENZOYL UREA DERIVATIVES AND PHENANTHROLINE
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Expanded Porphyrin Exhibiting Off-Centered Out-of-Plane Coordination to Dysprosium
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作者 Dmitry I.Nazarov Jorge Labella +6 位作者 Alexey V.Kuzmin Maxim A.Faraonov Evgenii N.Ivanov Salavat S.Khasanov Tomas Torres Mikhail K.Islyaikin Dmitri V.Konarev 《CCS Chemistry》 CSCD 2024年第7期1731-1738,共8页
The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular magnets.In this context,the use of expanded porphyrinoids remains elusive since their coordin... The complexation of high-spin lanthanides to porphyrinoids is a powerful strategy for the development of advanced molecular magnets.In this context,the use of expanded porphyrinoids remains elusive since their coordination chemistry is challenging to control.Herein,taking inspiration from on-surface chemistry,we explored the coordination of Dy^(3+)to a six-membered porphyrinoid,namely,the hemihexaphyrazine H3Hhp.Remarkably,we observed the selective formation of a mono-nuclear off-centered,out-of-plane H_(2)Hhp-Dy^(3+)complex when performing the complexation under reductive conditions.During this reaction,the oxidation state of the macrocycle did not change.Employing X-ray diffraction analysis,we found that the coordination number of Dy in this complex was 8.The macrocycle cocrystallized with decamethylcobaltocene(Cp_(2)^(*)Co)molecules,giving rise to a wellordered solid-state packing,governed byπ-πinteractions.As a result of this organization,a small magnetic coupling between the neighboring molecules was observed.All in all,this work provides key insights into the coordination of magnetically active metals with expanded porphyrinoids,thus motivating the development of advanced spintronic devices. 展开更多
关键词 PORPHYRINS dysprosium MACROCYCLE coordination chemistry MAGNETISM
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Steric hindrance effect of Schiff-base ligands on magnetic relaxation dynamics and emissive behavior of two dinuclear dysprosium complexes 被引量:3
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作者 Youdong Jiang Sourav Dey +5 位作者 Hongshan Ke Yongsheng Yang Lin Sun Gang Xie Sanping Chen Gopalan Rajaraman 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第7期1049-1057,I0003,共10页
The self-assembly reactions between mixed-ligand and tetrahydrate dysprosium acetate in the presence of mixed organic solvents lead to two structural similar dinuclear dysprosium complexes with composition formulas of... The self-assembly reactions between mixed-ligand and tetrahydrate dysprosium acetate in the presence of mixed organic solvents lead to two structural similar dinuclear dysprosium complexes with composition formulas of Dy_(2)(L_1)_(2)(L_(2))_(2)(CH_(3)OH)_(2)·CH_(2)Cl_(2)·CH_(3)OH(1) and Dy_(2)(L_1)_(2)(L_(3))_(2)(CH_(3)OH)_(2)·CH_(3)CN(2),where L_1,L_(2) and L_(3) represent the deprotonated form of 4-tert-butyl-2-(7-methoxybenzo[d]oxazol-2-yl)phenol,(E)-1-(((3,5-di-tert-butyI-2-hydroxyphenyI)imino)methyl)naphthalen-2-ol and(E)-2,4-di-tertbutyl-6-((2-hydroxybenzylidene)amino)phenol.The tiny difference of the core structure of 1 and 2 is derived from the steric hindrance of Schiff base ligands L_(2) and L_(3).Dynamic magnetic measurements reveal that 1 and 2 show frequency-dependent out-of-phase alternating-current susceptibility signal peaks at different temperatures under zero dc field,diagnostic of single-molecule magnet behavior.The experimental derived energy barrier to magnetization reversal for 1 and 2 is 108(1),47(2) and 33(3) K.Ab initio CASSCF calculations performed on 1 and 2 suggest that the origin of the difference in magnetic properties originates from the variation in the single-ion anisotropy that arises due to minor structural variation.Further,the equation to calculate the effective energy barrier for Dy_(2) proposed earlier is found to yield an excellent agreement with the experimental results.Solid state fluorescence measurements performed on 1 and 2 demonstrate that both exhibit two ligands centered components of fluorescent emissive,in addition,with different emitting colors and chromaticity coordinates.The discrepancy of fluorescence and single molecule magnet behavior showed by 1 and 2 can be attributed to the steric hindrance effect of Schiff base ligands. 展开更多
关键词 Fluorescent single-molecule magnets Dinuclear dysprosium complexes Mixed ligand Steric hindrance Theoretical calculations Rare earths
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Slow magnetic relaxation in a 3D dysprosium(Ⅲ)-fluoro-oxalate framework containing zig-zag [Dy-F]n chains 被引量:2
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作者 Leilei Li Yifan Fang +2 位作者 Shuang Liu Mingfei Hu Wenzhen Wang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第1期100-107,共8页
Dysprosium complexes based on [F-Dy] or near-linear [F-Dy-F] unit are of great concern in the field of single-molecule magnets due to their large magnetic anisotropy.Here,the crystal structure and the magnetic relaxat... Dysprosium complexes based on [F-Dy] or near-linear [F-Dy-F] unit are of great concern in the field of single-molecule magnets due to their large magnetic anisotropy.Here,the crystal structure and the magnetic relaxation dynamics were reported for a three-dimensional(3 D) metal-organic framework(MOF):[DyF(C_(2)O_(4))(H_(2)O)2]n·2nH_(2)O(1),which is the unique MOF containing zig-zag [Dy-F]_(n) chains.Magnetic susceptibility characterization reveals that 1 is one of the few 3 D MOFs which show slow magnetic relaxation under zero dc field.And the effective energy barrier of 72 K for 1 is also higher than most Dy-based 3 D MOFs.The diamagnetic ion dilution study shows that the ferromagnetic exchange couplings mainly transmitted by F^(-) bridges in 1 contribute little to the energy barrier,but effectively suppress the quantum tunneling process and result in a smooth hysteresis loop with no waist-restricted step. 展开更多
关键词 dysprosium complex FLUORIDE Magnetic property Slow magnetic relaxation Exchange coupling Rare earths
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Surface hardness,thermal,optical,and photon attenuation coefficients assessment for dysprosium-doped tellurite glasses 被引量:1
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作者 Hesham M.H.Zakaly D.E.Abulyazied +2 位作者 H.A.Saudi B.M.Alotaibi Shams A.M.Issa 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第7期1083-1090,I0004,共9页
Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed... Using a melt-cooling process with the host glass,Dy_(2)O_(3)(1 wt%,2 wt%,3 wt%,and 4 wt%) doped tellurite glasses were produced.A(65-x)TeO_(2)-20B_(2)O_(3)-10Al_(2)O_(3)-SGeO_(2)-xDy_(2)O_(3) glass system was analyzed by Xray diffraction.The patterns have a hump at 2θ=27°-29° and no sharp peaks,indicating that all the glass samples are amorphous.The Vickers microhardness determines how resistant a glass is to persistent deformation produced by a harder substance.Differential scanning calorimetry(DSC) at 300-550℃ was used to evaluate the thermal properties of the Dy_x glass samples.The glass transition temperature T_g(small endothermic peak),start crystallization temperature T_x and crystallization temperature T_c can all be seen on the DSC thermogram(exothermic peaks).The UV-Vis transmittance and absorption spectra were measured.The optical data show that the values of E_d^(ir),E_g^(Ind) and E_U decrease as the amount of Dy_(2)O_(3)increases,indicating a narrowing of the tails due to localized states in the forbidden gap.A concentration quenching event occurs when Dy^(3+) concentrations are above a certain threshold(1%).The addition of Dy_(2)O_(3) increases glass density,while the addition of other Dy(Ⅲ) oxides increases sample density.The radiation shielding values change as a consequence of density fluctuation.The sample with the highest amount of Dy_(2)O_(3)(Dy_(4)) has stronger radiation shielding characteristics;hence,it is superior in terms of shielding outcomes at all energy levels.Such Dy_x samples can be used in various forms of ionizing radiation shielding. 展开更多
关键词 Melt-cooling process DSC dysprosium(Ⅲ)oxides Surface hardness Photon attenuation Rare earths
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