A new liquid membrane diffusion model for characterizing the adsorption kinetics of europium by using a continuous measurement of adsorption platform

To explore the kinetic adsorption under continuous and nonequilibrium states, an integration of continuous measurement and adsorption platform kinetics method was proposed, which was initially called the ICM-AP kinetics method, and a corresponding kinetic adsorption experimental method was developed. Adsorption experiments of europium(Eu) on Ca-bentonite,Na-bentonite, and the D231 cation exchange resin were performed using the ICM-AP kinetics method and continuous measurements. Because the kinetic experimental results observed in this study were different from those of traditional batch adsorption data, pseudo-first-order or pseudo-second-order kinetic models were unsuitable for fitting the experimental data.Hence, a liquid membrane diffusion(LMD) model was developed based on the assumption of simultaneous adsorption/desorption to discuss the mechanism of kinetic adsorption. The kinetic adsorption mechanism was also studied by using XPS.The results indicated that the proposed adsorption model can fit the experimental data more suitably, and the adsorption/desorption behaviors of Eu on bentonite and the D231 resin were simultaneously observed, suggesting that the adsorption kinetics of Eu(Ⅲ) was mainly dominated by hydrated Eu(Ⅲ) ions on the liquid membrane.

Eu^(3+)-昆布多糖杂化材料的制备及其识别海水中铁离子的研究

稀土杂化材料在照明、发光、生物医药、光纤通信等领域中具有广泛的应用和发展前景,成为许多领域的研究热点。随着工业废物排放、沿海建设等一系列人类活动的进行,增加了海水中金属离子的浓度。本实验设计了一种独特的Eu^(3+)杂化材料,这种材料中含有昆布多糖、2-噻吩甲酰三氟丙酮(TTA)和邻菲罗啉(phen)三种配体,这三种配体对Eu^(3+)的发光有敏化作用。制备得到的Eu^(3+)-昆布多糖杂化材料融合了Eu^(3+)的发光特性和昆布多糖无毒、生物相容性等特征。这种新型杂化材料可附载到水下探测装置中,应用于海水中铁离子的监测。

Synthesis and characterization of arginine-modified and europium-doped hydroxyapatite nanoparticle and its cell viability

The arginine-modified and europium-doped hydroxyapatite nanoparticles（HAP-Eu） were synthesized by hydrothermal synthesis.The prepared nanoparticles were characterized by transmission electron microscopy（TEM）,X-ray diffractometry（XRD）,Fourier transform infrared（FTIR） and zeta potential analyzer.The cell viability of HAP-Eu was tested by image flow cytometry.The results indicated that HAP-Eu is short column shapes and its size is approximately 100 nm,its zeta potential is about 30.10 mV at pH of 7.5,and shows no cytotoxicity in human epithelial cells and endothelial cells.

Equilibrium analysis of solvent extraction of yttrium (Ⅲ) and europium (Ⅲ) from hydrochloric acid with P_(507)

For the accurate prediction of equilibrium distribution ratios of rare earth metals during solvent extraction under non-ideal conditions, the extraction equilibria of yttrium （Ⅲ） and europium （Ⅲ） from the hydrochloric acid solutions with P507 in Shellsol D70 were studied. A chemically-based model was established and the extraction equilibrium constants were determined by the nonlinear least squares method. The proposed model involves the cation exchange reaction and the solvation extraction in the low and high acidity regions, respectively. In the model, the nonideality of the aqueous phase and was corrected by considering the complexation of the metals with Cl- and by replacing with its effective concentration, respectively. This model was verified by fair agreement between the calculated metal distribution ratios and those experimentally obtained in the single metal systems. The feed concentrations for the systems are in wide ranges of the metal （up to 0.1 mol/L）, hydrochloric acid （0.07-3.00 mol/L） and the extractant （0.25-1.00 mol/L）. The model enables the engineering prediction of the equilibrium distribution ratios with good accuracy in a binary metal system.

Synthesis and Luminescence Property of Hierarchical Europium Oxalate Micropaticles

Hierarchical europium oxalate Eu2（C2O4）3.10H2O micro-particles were synthesized through a simple precipitation method at room temperature in present of trisodium citrate. The products were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy, and photoluminescence. The possible formation mechanism of the hierarchical europium oxalate Eu2（C2O4）3.10H2O micro-particles was discussed.

Eu(Ibu)_(3)phen配合物的合成表征及发光性

以药物布洛芬为第一配体,稀土离子Eu(Ⅲ)为中心离子,采用溶剂法合成了Eu^(3+)、布洛芬(Ibu)和邻菲罗啉(phen)的稀土-布洛芬药物配合物Eu(Ibu)3phen,采用元素分析、紫外光谱、红外光谱对配合物进行了初步结构表征,并研究了配合物的荧光性能.结果表明,该合成方法简单,Eu(Ibu)_(3)phen产率较高,配合物Eu(Ibu)_(3)phen的荧光发射光谱在612 nm出现Eu离子强特征荧光发射峰.该配合物有较好的发光性能,可作为安全环保的荧光材料.

红色荧光粉CaAlSiN_(3)∶Eu^(2+)的结构精修和性能

运用高温固相法合成系列掺铕(Eu)的氮化物荧光粉Ca1-xAlSiN_(3)∶xEu^(2+),对所得到的最佳样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)进行系列表征和结构精修.结果表明,样品Ca_(0.99)AlSiN_(3)∶0.01Eu^(2+)的晶粒尺寸为10μm左右,各元素分布均匀,其精修图与实测XRD谱图基本吻合,属于正交晶系结构.该样品的色坐标为(0.645 1, 0.354 5),落在红光区域,色纯度高达100%,相关色温为2 449 K,属于低色温.该荧光粉在298~473 K范围内表现出良好的热稳定性,活化能为0.26 eV,具有广阔的市场前景.

Eu掺杂ZnO多孔片状材料的制备及其降解印刷染料RhB

采用常温络合-水解法构筑Eu掺杂Zn O多孔片状材料。通过SEM、TEM、XRD、EDS等表征手段证明稀土元素Eu成功掺杂到Zn O之中,Eu-Zn O的形貌为多孔片状结构。研究了Eu-Zn O多孔片状材料对染料的光催化性能。结果表明:该材料对Rh B具有较好的降解效率,降解效率高达99.2%,循环稳定性能高达98.3%,远大于商用Zn O的76.2%的降解效率和82.3%的循环稳定性能,由以上数据说明Eu-Zn O具有很好的光催化降解效率和循环稳定性能。其优异的光催化性能归因于稀土元素Eu掺杂和多孔片状结构。

Effects of Cerium Doping at Ti Sites and Europium Doping at Ba Sites on Dielectric Properties of BaTiO_3 Ceramics

Two special rare earth elements cerium and europium were chosen to conduct chemical modification of the BaTiO3 structure. The cold-pressing ceramic processing technique was used to prepare barium titanate ceramics doped with Ce at Ti sites and with Eu at Ba sites on the base of formulas Ba （ Ti1 -x Cex ） O3 （x = 0. 05, 0. 10 ） （CBT） and （ Ba1-y Euy ） Ti1-x/8O3 （ y = 0. 05, 0. 10） （EBT）. Associated with structures and microstructures, the effects of cerium and europium doping on dielectric properties of BaTiO3 ceramics were discussed. The CBT ceramics exhibit a pseudocubic perovskite structure, while the EBT ceramics exhibit a tetragonal perovskite structure with the exception of the existence of a small percentage of the Eu2Ti2O7 phase. The Curie peak of BaTiO3 shifts towards room temperature at rates of 3 ℃/mol Ce atoms and 10 ℃/mol Eu atoms（ Eu≤5% ）, respectively. Compared with the CBT ceramics, the EBT ceramics show significant advantages, such as a narrow fine grain size distribution（ 1 μm）, a lower porosity and a higher density（5.85 g/cm^3）, more stable dielectric-temperature dependence（ ε′= 1600-1800 at t 〈 50℃ ） and a lower dissipation factor（ 〈 0. 05 ）. The stability of dielectric constant with frequency in BaTiO3 can extend to 107 Hz due to Ce and Eu doping.

基于Eu^(3+)-生物质碳量子点探针的比率型荧光传感体系检测盐酸四环素

该文以橙皮为原料制备的碳量子点(CDs)与铕离子(Eu^(3+))构建双发射比率型荧光探针(Eu^(3+)-CDs)并用于抗生素盐酸四环素的检测。在370 nm激发波长下,Eu^(3+)-CDs荧光探针在425 nm处出现较强的蓝色荧光峰,在617 nm处出现较弱的红色荧光峰。随着盐酸四环素浓度的逐渐增大,Eu3+与盐酸四环素螯合形成的配合物增多,在425 nm处的CDs荧光(I_(F425))逐渐减弱,而617 nm处铕配合物的荧光(I_(F617))逐渐增强,可基于荧光强度比I_(F617)/I_(F425)的变化对盐酸四环素进行测定。考察了Eu^(3+)的浓度、pH值和反应时间对探针荧光强度的影响。在最佳条件下,该双发射比率型荧光探针对盐酸四环素具有特异性识别能力,荧光强度比(I_(F617)/I_(F425))与盐酸四环素浓度在10~100µmol/L范围内存在良好的线性关系,相关系数r^(2)=0.9926,检出限为5.09µmol/L。该方法成功用于猪肉中盐酸四环素含量的检测,加标回收率为102%~110%,相对标准偏差为0.20%~2.4%,具有较好的实用性。

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

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 conjugate.Samples were extracted with methanol/water...

Progresses in electroluminescence based on europium(Ⅲ) complexes

The research on electroluminescence based on europium（III） complexes has come to an important phase. This article reviewed the progresses in photoluminescence and electrohiminescence of Eu（III） complexes in recent years from the views of the design of Eu（III） complexes and optimization of device structures, and discussed some important factors influencing electroluminescence performance. The problems existing in the practical application such as the volatility and thermal stability of Eu（III） complexes in this area were discussed, and the possible corresponding solutions were briefly prospected.

Effects of Lanthanum and Europium on Rooting of Plantlet Eriobotrya Japonica Lindl. in vitro

The effect of La 3+ and Eu 3+ on the rooting of Eriobotrya japonica Lindl. plantlet in vitro was studied with adding La 3+ and Eu 3+ to the rooted medium. The rooting rate, the number of root and the length of root were studied after transplanting 20 d. The activity of peroxidase, nitrate reductase and fresh weight of roots were determined after transplanting 44 d. The results show that the optimum concentration range of La 3+ (1.0～3.0 μmol·L -1), Eu 3+ (2.0～3.0 μmol·L -1) in the rooted medium can increase the rooting rate and the fresh weight of roots, and promote the length of root and raise the activities of peroxidase and nitrate reductase significantly. La 3+ has more effect in improving the rooting rate, root length and the activities of peroxidase and less effect in promoting root fresh weight and the activities of nitrate reductase than Eu 3+.

高压水蒸气对β-Li_(2)TiO_(3:)Eu^(3+)荧光粉的全谱发光性能影响

采用水热法制备荧光粉前驱体后通过高温煅烧的方法,合成了由电偶极跃迁主导的高色纯度的β-Li_(2)TiO_(3):Eu^(3+)红色荧光粉.设计了适用于DHT11的拓扑电路,对荧光粉体湿度和温度进行测试.研究发现,高压腔体中加水量为5 mL,β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)的相对湿度可达81%RH.在波长为396 nm的近紫外光激发下,β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)发射由电偶极跃迁主导的613 nm的红光,荧光寿命为773.36μs,高压水蒸气处理对β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)的电偶极跃迁发射峰和磁偶极跃迁发射峰位置没有变化,但发射峰强度增强并且荧光寿命降至386.81μs.高压水蒸气高压处理后的荧光粉色坐标x=0.47,y=0.51,色温为3300 K,红光色纯度为96.6%,比高压处理前显示出更优异的显色性能.高压水蒸气处理后的β-Li_(2)TiO_(3):0.5 mol%Eu^(3+)电偶极跃迁谱线强度参数Ω_(2)增加至4.21×10^(-19)cm^(2),^(5)D_(0)→^(7)F_(2)跃迁的荧光分支比β2也增加至96.9%,而量子效率η减小至57%,证实了湿度对荧光粉的发光效率具有极大的影响.

Coating Carbon Nanotubes with Europium Oxide

Carbon nanotubes (CNTS) coating with europium oxide by a simple method is reported in this letter for the first time. The CNTS were refluxed in a solution of nitric acid containing europium nitrate, and the pH value was subsequently ajusted with ammonia solution. At last, the mixture was filtered and annealed. The TEM micrograph showed that the CNTS were covered with a uniform thin layer with thickness of about 15 nm. The XRD results revealed that the CNTS were coated with europium oxide.

Synthesis and Photoluminescence of New Europium Complex Eu(DBM)_3(DPPZ) with Dipyridophenazine Ligand

Dipyrido [3, 2-a:2,3-c] phenazine moiety has been introduced as neutral ligand in europium complex. Therefore, a new europium complex with saturated emission, strong fluorescent intensity and good solubility was designed and synthesized for the first time. Its photoluminescence and UV properties were examined. The experimental results showed that this new Eu-complex could be used as red electroluminescent materials.

Hydrothermal Synthesis and Characterization of Europium-doped Barium Titanate Nanocrystallites

Barium titanate nanocrystallites were synthesized by a hydrothermal technique from barium chloride and tetrabutyl titanate. Single-crystalline cubic perovskite Ba TiO_3 consisting of spherical particles with diameters ranging from 10 to 30 nm was easily achieved by this route. In order to study the influence of the synthesis process on the morphology and the optical properties, barium titanate was also prepared by a solid-state reaction. In this case, only the tetragonal phase which crystallizes above 900 was observed. High-temperature X-ray diffraction measurements were performed to investigate the crystallization temperatures as well as the particle sizes via the Scherrer formula. The lattice vibrations were evidenced by infrared spectroscopy. Eu^(3+)was used as a structural probe, and the luminescence properties recorded from Ba TiO_3 :Eu^(3+)and elaborated by a solid-state reaction and hydrothermal process were compared. The reddish emission of the europium is increased by the nanometric particles.

Synthesis,Characterization and Fluorescence Properties of Europium,Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline

Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen) L3·1/2H2O; Tb (phen) L3·H2O and Tb0.5 RE0.5(Phen)L3·1/2H2O. (RE = Y3+, La3+ and Gd3+; L = biphenyl 4-carboxylic acid; phen = o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE (III ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3 + is raised by inert fluorescent rare earth ions (Y3+ , Gd3+ and La3+ ), but in Tb3+ hetero-nuclear rare earth complexes the intensity of Tb3+ ions are quenched by the inert fluorescent rare earth ions.

Synthesis,crystal structure and fluorescence of a new europium complex with 2-bromobenzoate and 2,2'-bipyridine

A new complex of {[Eu2(2-BrBA)6(2,2’-bpy)2]2·CH3CH2OH·H2O} (2-BrBA=2-bromobenzoate; 2,2’-bpy=2,2’-bipyridine) was prepared by solvent method and characterized with X-ray single-crystal diffraction, IR spectroscopy, UV spectroscopy, and fluorescence spectroscopy. The complex crystallized in triclinic crystal system, Pī space group, with a=1.17196(4) nm, b=2.36142(9) nm, c=2.59151(9) nm, α=113.266(2)°, β=101.100(2)°, and γ=94.400(2)°. Two independent dinuclear molecules were contained in the asymmetric unit. The two molecules were similar to each other. Each Eu(Ⅲ) ion was nine-coordinated with seven oxygen atoms from five 2-BrBA ligands and two nitrogen atoms from 2,2’-bpy molecule. The carboxylate groups acted as bidentate-chelating, bidentate-bridging and chelating-bridging coordination modes. The complex adopted a distorted monocapped square-antiprism coordination geometry. Five peaks at 579, 591, 613, 652, and 697 nm appeared in the fluorescence spectrum, corresponding to 5D0→7F0, 5D0→7F1, 5D0→7F2, 5D0→7F3, and 5D0→7F4 transition emissions of the Eu(Ⅲ) ion, respectively.

Crystal Structure and Properties of Europium m-Chlorobenzoate Complex with 1,10-Phenanthroline

A europium m-chlorobenzoate complex with 1,10-phenanthroline [Eu(m-ClBA)_3(phen)]_2 single crystal, where m-ClBA=m-chlorobenzoate and phen=1,10- phenanthroline,was prepared and structurally characterized by X-ray diffraction. It crystallizes in triclinic, space group P1- with a=1.10138(8)nm, b=(1.18606(9) nm,) c=1.32516(10) nm, α=112.5390(10)°, β=92.1700(10)°, γ=101.6220(10)°,(C_(66))H_(40)N_4O_(12)Cl_6Eu_2, M_r=1597.64, V=1.5533(2) nm^3, Z=1, D_c=1.708 g·cm^(-3), μ(Mo Kα)=2.325 mm^(-1), (F(000))= 788, the final R=0.0424 and wR=0.0899 for 6856 independent reflections with R_(int)=(0.0776.)The crystal consists of binuclear molecules of the title compound. Each Eu^(3+) ion is nine-coordinated to one 1,10-phenanthroline molecule, one bidentate carboxylate group and four bridging carboxylate groups. The carboxylate groups are bonded to the europium ion in three modes: the chelating bidentate, the bridging bidentate and bridging-chelating thridentate. Excitation and luminescence data observed at room temperature show that the title complex (emits) very intensive red fluorescence under ultraviolet light. The results of thermal analysis indicate that the complex [Eu(m-ClBA)_3(phen)]_2 is quite stable to heat.