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Na_2BaMg(PO_4 )_2:synthesis, crystal structure and europium photoluminescence properties

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Journal of Rare Earths 2013年第9期31卷 849-856页

作者： Amal Boukhris Mourad Hidouri Benoit Glorieux Mongi Ben Amara UR:Inorganic Materials Faculty of ScienceUniversity of Monastir Institute for Condensed Matter Chemistry of Bordeaux CNRS University of Bordeaux I87Avenue of Dr.A.Schweitzer33608 Pessac-CedexFrance

Na2BaMg（PO4）2 was synthesized and characterized by X-ray diffraction, differential thermal analysis （DTA）, 31p NMR spectroscopy and photoluminescence measurements. This compound crystallized in the P3 ml space group of the trigonal system with the parameters of equivalent hexagonal cell a=0.5305（1） nm and c=0.6986（3） nm. The structure showed a perfect isotipysm with the mineral glaserite KaNa（SO4）2. Thus, it exhibited a lamellar framework which could be described as the stacking along the [001] direc- tion of [MgP2O84-]∞ layers of comer sharing MgO6 polyhedra and PO4 tetrahedra. The Ba2＋ cations were located within the interlayer space, while the Na＋ ones were found in large cavities bound to the layers. The DTA analysis showed that this compound melt con- gruently at 1385 K. The 31p NMR spectrum was consistent with the presence of a single phosphorus site in the structure. Optical properties were investigated for the 5% doped Eu3＋ and Eu2＋ phases. The trivalent europium was used as a local probe, replacing bar- ium while the divalent europium was used to examine whether this material could be used as an optical applications.

关键词： phosphate 31p NMR crystal structure europium photoluminescence rare earths

Synthesis and photocatalytic performance of europium-doped graphitic carbon nitride

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Journal of Rare Earths 2013年第11期31卷 1085-1091页

作者：徐冬冬李晓妮刘娟黄浪欢 Department of Chemistry Jinan University

europium-doped graphitic carbon nitride was synthesized by an easy method and characterized by X-ray diffraction （XRD）, ultraviolet-visible diffuse reflection spectroscopy （UV-Vis DRS）, Fourier transform infrared spectroscopy （FTIR）, photolu- minescence spectra （PL） and transmission electron microscopy （TEM）. The effect of dopant concentration on the rate of photocata- lytic degradation was investigated through degrading methylene blue aqueous solution. The results indicated that the europium-doped samples all possessed increased photocatalytic activity and the optimal europium content was 0.38 wt.%. Moreover, a possible photo- catalytic mechanism for the europium-doped graphitic carbon nitride was proposed.

关键词： graphitic carbon nitride europium photocatalytic synthesis doping rare earths 1

Synthesis and photoluminescent performance of novel europium(Ⅲ) carboxylates with heterocyclic ancillary ligands

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Rare Metals 2022年第4期41卷 1342-1352页

作者： Priyanka Dhankhar Rekha Devi Sushma Devi Sangeeta Chahar Mandeep Dalal V.B.Taxak S.P.Khatkar Priti Boora Department of Chemistry Maharshi Dayanand UniversityRohtak 124001India

Five novel europium(Ⅲ)complexes with 2-[4-(dibutylamino)-2-hydroxybenzoyl]benzoic acid(DAHB)as primary ligand and bathophenanthroline(batho),2,2’-bipyridyl(bipy),5,6-dimethyl-1,10-phenanthroline(dmph),1,10-phenanthroline(phen)as ancillary ligands were syn-thesized via solution precipitation *** structural formulae of synthesized complexes were speculated to be Eu(DABH)_(3)·2H_(2)O(C1),Eu(DABH)_(3)·batho(C2),Eu(DABH)_(3)·bipy(C3),Eu(DABH)_(3)·dmph(C4)and Eu(DABH)_(3)·phen(C5)by elemental analysis,infrared spectroscopy and proton nuclear magnetic resonance spec-troscopy(^(1)H-NMR).The photoluminescent properties and thermal stability of the complexes were investigated by photoluminescent spectroscopy and thermogravimetric analysis(TG-DTG),*** Commission Inter-nationale de I’Eclairage(CIE)color coordinates,Judd–Ofelt intensity parameter(Ω_(2)),total quantum yield,intrinsic quantum efficiency and energy transfer dynamics of com-plexes were also *** excitation spectra of com-plexes are extended up to visible *** complexes exhibit characteristic photoemission of Eu^(3+)metal ion with high color purity in red region attributed to efficient energy transfer from ligand to metal *** replacement of water molecules from coordination sphere of europium ion by ancillary ligands results in enhancement of luminescent properties of the C2–C5 complexes,indicating that ancillary ligands act as additional light harvesting centers in sensiti-zation *** thermal studies show that these complexes are suitable for meeting the requirement of temperature for fabrication of OLEDs devices.

关键词： Photoluminescence europium Sensitization Aromatic carboxylic acid Energy transfer dynamics

Potential application of graphene oxide and Aspergillus niger spores with high adsorption capacity for recovery of europium from red phosphor,compact fluorescent lamp and simulated radioactive waste

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Journal of Rare Earths 2023年第1期41卷 157-166页

作者： B.Arunraj Vidya Rajesh N.Rajesh Department of Chemistry Birla Institute of Technology and Science-PilaniHyderabad CampusShameerpetHyderabad 500078India Department of Biological Sciences Birla Insttute of Technology and Science-PilaniHyderabad CampusShameerpetHyderabad 500078India

The recovery of rare earth elements(REEs) is a global challenge and the mining of rare earths has serious environmental implications due to the toxic waste released post ***,the rising demand for rare earths and their far reaching electronic applications necessitates an effective strategy to recover the REEs from more viable *** this work,the graphene oxide-Aspergillus niger spores(*** spores) blend was utilized for adsorptive recovery of a precious rare earth Eu(Ⅲ) and the adsorption variables like pH of the medium,adsorbent dosage,sorption kinetics,thermodynamics,and isotherm were optimized for the developed bioso *** adsorption process suits the Langmuir isotherm model with a maximum adsorption capacity of 147.3 mg/*** pseudo-second-order kinetics is a perfect fit to describe the adsorption *** results obtained through the Van’t Hoff plot show negative free energy change(ΔG^(0)) which implies the spontaneity of the adsorption *** negative standard enthalpy change(ΔH^(0)) values show that the nature of the adsorption process is *** analytical characterizations including Fourier transform infrared spectroscopy(FTIR),Raman,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),Brunauer-Emmett-Teller(BET),thermal gravimetric analysis(TGA),and scanning electron microscopy-energy dispersive X-ray spectroscopy(SEM-EDX) were employed to study the *** features of *** spores biosorbent were applied to recover Eu(Ⅲ) from real samples such as fluorescent lamp phosphor,red phosphor powder,and a simulated radioactive waste solution.

关键词： europium Graphene oxide Aspergillus niger Phosphor Radioactive waste Rare earths

Time-resolved fluoroimmunoassay of zearalenone in cereals with a europium chelate as label

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Journal of Rare Earths 2009年第6期27卷 1088-1091页

作者：马智鸿黄飚张珏张艺朱岚屠蔷 Jiangsu Institute of Nuclear Medicine Key Laboratory of Nuclear MedicineMinistry of Health Department of Pharmaceutical and Molecular Biotechnology School of BiotechnologyKey Laboratory of Industrial BiotechnologyMinistry of EducationSouthern Yangtze University

A competitive indirect time-resolved fluoroimmunoassay(TRFIA) was developed for detection of zearalenone(ZEN) in cereals,in which ZEN conjugated to bovine serum albumin(BSA) is used as solid-phase antigen.A competitive indirect TRFIA was conducted by simultaneously incubating ZEN in standard or extracted samples with anti-ZEN monoclonal antibody over ZEN-BSA coated plates,and then determining the bound ZEN monoclonal antibody with goat anti-mouse europium *** were extracted with methanol/water...

关键词： time-resolved fluoroimmunoassay zearalenone europium rare earths food safety

Synthesis and Fluorescence of europium-Doped Barium Fluoride Cubic Nanocolumns

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Journal of Rare Earths 2004年第1期22卷 79-82页

作者：连洪州刘洁叶泽人石春山 Key Laboratory of Rare Earth Chemistry and Physics

europium-doped barium fluoride cubic nanocolumns were synthesized from the quaternary water in oil reverse microemulsions. In this process, the aqueous cores of water/cetyl trimethyl ammonium bromide (CTAB)/n-butanol/n-octane reverse microemulsions were used as microreactors for the precipitation of europium doped barium fluoride. XRD analysis shows that under the dopant concentration of 0.06% (molar fraction), the products are single phase. The result products are cubic column-like with about 30～50 nm edge length of cross section, and about 200 nm of length obtained from the transmission electron microscopy (TEM), and atomic force microscopy (AFM). Under the 0.06% (molar fraction) of dopant concentration, the fluorescence of Eu 2+ and Eu 3+ under the 589 of excitation wavelength is observed.

关键词： optics europium barium fluoride cubic nanocolumns rare earths

Synthesis,structure and spectroscopic studies of europium complex with S(+)-mandelic acid

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Journal of Rare Earths 2011年第12期29卷 1188-1191页

作者： M.Babij A.Mondry Faculty of Chemistry University of Wrocaw

The Eu^3＋ complexes with S（＋）-mandelic acid were synthesized in the form of powders by mixing aqueous solutions of EuCl3, S（＋）-mandelic acid and NaOH in different molar ratios. The powders were characterized by elemental analysis, X-ray powder diffraction （XRPD.） method, Fourier transform infrared （FTIR） and Raman spectroscopy, UV-vis reflectance and luminescence spectra as well as luminescence lifetime measurements. It was found that all studied powders of Eu^3＋ complexes with S（＋）-mandelic acid were isostructural and crystalline and formed compounds with the formula Eu（Man）3（H2O）2.

关键词： europium mandelic acid emission FTIR spectroscopy Raman sDectroscopy rare earths

New complexes of heteroaromatic N-oxides with europium,uranyl and zinc ions

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Journal of Rare Earths 2012年第6期30卷 552-558页

作者： Zbigniew Hnatejko Faculty of Chemistry Adam Mickiewicz UniversityGrunwaldzka 660-780 PoznańPoland

New solid complexes of europium, uranyl and zinc ions with N-oxides of 4-chloro-2,6-dimethylpyridine, quinoline and 4-meth- oxyquinaldinic acid in presence different anions were obtained and characterized by elemental and TG analyses, IR and luminescence spectra. The compounds are crystalline, hydrated or anhydrous salts with colours typical of metal ions. Thermal studies showed that in hydrated salts lattice or coordination water molecules are present. A role of different anions in the formation of various types of the complexes is presented.

关键词： complexes europium 4-methoxyquinaldinic acid N-oxide 4-chloro-2,6-dimethylpyridine N-oxide quinoline N-oxide uranyl zinc

Determination of Doxycycline by europium Ion Fluorescence Probe Sensitized by Surfactant

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Journal of Rare Earths 2005年第S1期23卷 19-22页

作者：敖登高娃张莹樊海燕 College of Chemistry and Chemical Engineering Inner Mongolia University Hohhot 010021 China

The fluorescence property of europium(Ⅲ)-doxycycline(DC) complex and the effect of reaction condition were studied. It is found that in the buffer solution of Na_2B_4O_7-NaOH at pH 9.63 europium can react with doxycycline to form a complex. After intramolecular energy transfer, the system shows the characteristic fluorescence of Eu 3+. The fluorescence intensity can be enhanced again in addition of non-ionic surfactant Triton X-100 with λ_ ex=375 nm, λ_ em=617 nm. Based on this, a new method using europium ion as fluorescent probe for the determination of trace doxycycline was proposed. The fluorescence intensity is linearly related to the doxycycline concentration in the range of 2.8×10 -6～2.46×10 -5 mol·L -1 with correlation coefficient 0.9973. The detection limit was 1.35×10 -8 mol·L -1. It is applied to the determination of doxycycline in pharmaceutical preparations and in serum satisfactorily. The recovery is within the range of 93%～103%.

关键词： doxycycline europium surfactant fluorescence spectrophotometry rare earths