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Study on the energy transfer between UO_2^(2+) and Eu^(3+) in sol-gel derived titania matrix by luminescence spectroscopy

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Chinese Journal of chemistry 1999年第2期17卷 132-136页

作者：符连社张洪杰王淑彬孟庆国杨魁跃倪嘉缵 laboratory of rare earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

The TiO2 gel doped with UO22+ and Eu3+ has been prepared by a sol-gel method. The quenching of the UO22+ emission by Eu3+ and the energy transfer from the excited state of UO22+ to the ground state of Eu3+ have been investigated. The energy transfer has been studied by the measurement of luminescence lifetime τ, calculations of energy transfer efficiency ηET and energy transfer rate WET. The experimental results indicated that the quenching is combined static and dynamic mechanism, but the static mechanism is dominant.

关键词： Sol-gel method energy transfer titania uranyl ion europium

Luminescent properties of Ba_3(PO_4)_2:Eu,Tb phosphors

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Chinese Journal of chemistry 1996年第5期14卷 399-403页

作者： GAO,Yong SHI,Chun-Shanlaboratory of rare earth chemistry and physics.changchun institute of applied chemistry,Chinese Academy of Sciences,changchun,Jilin 130022,China laboratory of rare earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun Jilin 130022 China

Luminescence of europium (Ⅲ),europium(Ⅱ) and terbium(Ⅲ) has been observed in Bas(PO4)2:Eu,Tb phosphors which are synthesized in air *** valence state of europium is influenced by amount of *** is notable that the relative intensity of the emission spectra peaks corresponding to Eu2+ is increased if the amount of Tb3+ is *** phenomena can be explained by an electron transfer *** predict a new kind of two-rare-earth codoped trichromatic phosphors in Ba3(PO4)2 matrix.

关键词： Luminescence europium terbium phosphor

Computer Simulation for Effect of Tb^(3+) on Ca^(2+)Speciation in Human Plasma

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Journal of rare earths 2002年第3期20卷 238-240页

作者：卢兴王悦张海元王进平牛春吉倪嘉缵 key laboratory of rare earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Effect of Tb 3+ on Ca 2+ speciation in human plasma was studied by means of the computer program of MINTEQA2. When Tb 3+ ions are not added into the system, Ca 2+ ions mostly distribute in free Ca 2+ (74.7%) and the surplus distributes in Ca 2+ complexes, such as [CaHCO 3] +(7.9%), [Ca(Lac)] +(6.4%), CaHPO 4 (1 3%), [CaHistidinateThreoninateH 3] 3+ (2.4%), [CaCitrateHistidinateH 2] (2.3%) and CaCO 3(1.1%). Tb 3+ can compete with Ca 2+ for inorganic as well as biological ligands. An increase of concentration of Tb 3+ in the system results in an increase of content of free Ca 2+ and a decrease of contents of Ca 2+ complexes.

关键词： rare earths computer simulation speciation human plasma calcium terbium

Synthesis and Luminescence Properties of SBA-15 Functionalized with Covalently Bonded Terbium-Benzoic Acid Complex

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Journal of rare earths 2004年第z1期22卷 147-148页

作者： Peng Chunyun Zhang Hongjie Liu Fengwei Meng Qinguo Fu Lianshe Sun Lining Guo Junfang Yu Jiangbo key Lab of rare earth chemistry and physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China

Novel hybrid materials containing covalently bonded Terbium-benzoic acid complex in mesoporous silicaSBA-15 (denoted as Tb-SBA-15 ) were prepared via co-condensation of tetrethoxysilane (TEOS) and N-(4-benzoicacid-yl), N'-(propyltriethoxysilyl) urea (denoted as PABI).XRD, FTIR and luminescence spectroscopy were employed to characterize *** monitored by the ligand absorption wavelength (270 nm), Tb-SBA-15 displays the emission of Tb3+ (5D4→7Fj (j = 6, 5, 4, 3 ) transition) due to the energy transfer from the ligands to Tb3+.

关键词： SBA-15 covalently bonded terbium complex rare earths

Mild Hydrothermal Synthesis and Optical Properties of the Complex Fluoride KMgF_3 Doped with Eu

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Chinese Chemical Letters 2001年第11期12卷 1047-1050页

作者： Zhi Hong JIA Hai Quan SU Shou Hua FENG Chun Shan SHI key laboratory of rare earth chemistry and physics Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022 key laboratory of Inorganic Hydrothcrmal Synthesis Department of ChemistryJilin UniversityChangchun 130022

KMgF3 doped with Eu was synthesized by mild hydrothermal method at 240C for the first time. The excitation and emission spectra of the KMgF3 : Eu2+ phosphor were measured. Comparing with the sample synthesized through solid state reaction, the variation in the excitation spectra at 360 nm resulted from the existences of VK color centers; the low emission intensity was due to Eu2+ having transferred part energy to VK color centers.

关键词： Mild hydrothermal synthesis complex fluoride optical properties europium (II).

Hybridized valence electrons of 4f^(0-14)5d^(0-1)6s^2:the chemical bonding nature of rare earth elements

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Journal of rare earths 2017年第9期35卷 837-843页

作者：薛冬峰孙丛婷陈小艳 State key laboratory of rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

The chemical bonding nature of rare earth（RE） elements can be studied by a quantitative analysis of electron domain of an atom. The outer electrons of RE elements are within the valence shell 4f^（0-14）5d^（0-1）6s^2, which are involved in all chemical bonding features. We in this work found that the chemical bonding characteristics of 4f electrons are a kind of hybridizations, and classified them into three types of chemical bonding of 4f^（0-14）5d^（0-1）6s^2, furthermore, the coordination number ranging from 2 to 16 could thus be determined. We selected Y（NO_3）_3, La（NO_3）_3, Ce（NO_3）_3, YCl_3, LaCl_3, and CeCl_3 as examples to in-situ observe their IR spectra of chemical bonding behaviors of Y^（3＋）, La^（3＋） and Ce^（3＋） cations, which could show different chemical bonding modes of 4f and 5d electrons. In the present study, we obtained the direct criterion to confirm whether 4f electrons can participate in chemical bonding, that is, only when the coordination number of RE cations is larger than 9.

关键词： rare earth orbital hybridization coordination number chemical bonding 4f electrons

A review on solvent extraction of scandium

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Journal of rare earths 2022年第10期40卷 1499-1508页

作者： Dan Zou Yuefeng Deng Ji Chen Deqian Li State key laboratory of rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

This review article on the development course of scandium solvent extraction covers:(i)neutral phosphorus extractants;(ii)acid phosphorus extractants;(iii)carboxylic acid extractants;(iv)amine extractants;(v)chelating extractants;(vi)synergistic *** extractants are of valuable reference for developing new separation process of scandium from red mud,titanium dioride and other rare earth resources.

关键词： Scandium rare earths Solvent extraction Development course

Extraction and separation of thorium and rare earths with 5,11,17,23-tetra (diethoxyphosphoryl)-25,26,27,28-tetraacetoxycalix[4]arene

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Journal of rare earths 2012年第11期30卷 1142-1145页

作者：李艳玲卢有彩白彦廖伍平 State key laboratory of rare earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of Sciences

A calixarene derivative, 5,11,17,23-tetra（diethoxyphosphoryl）-25,26,27,28-tetraacetoxycalix[4]arene （L）, was studied for the extraction and separation of thorium and rare earths in nitrate medium. Thorium was extracted into the organic phase by a complex of Th（NO3）4·L with the logarithm of the equilibrium constant of 2.77. Thermodynamic functions, AH, AG and AS were calculated to be -2.49, -15.55 kJ/mol and 44.53 J/（mol·K）, respectively. The results indicated that this calixarene derivative might be used to separate thorium from rare earths and the separation factors were larger than 26. However, the salting-out agents affected the separation.

关键词： thorium rare earths phosphorylated calixarene solvent extraction

Structure and magnetic properties of new compounds CdYFeWO_7

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Journal of rare earths 2009年第6期27卷 1008-1012页

作者：吕敏峰武志坚孟健 State key laboratory of Application of rare earth Resources Changchun Institute of Applied ChemistryChinese Academy of Sciences

The solid solutions of CdYFeWO7,which are cubic pyrochlores of the type A2B2O7,have been prepared and their structures were determined using Ab initio *** refinement of the powder XRD data showed that CdYFeWO7 adopted cubic(Fd-3m) structure,while oxides crystallized in a defect-pyrochlore structure where both O(48f) and O (8b) sites were partially occupied,and the frustrated cations sublattice precluded long range ordering of Fe/W in the pyrochlore *** distribution analysis also sug...

关键词： frustrated magnetic materials structure determination magnetic properties rare earths