铈(Ⅲ)-氨基酸二元配合物与DNA的相互作用

本文应用循环伏安法和紫外光谱法研究了铈－ 色氨酸二元配合物（Ｃｅ（Ｔｒｐ）３ （（ＮＯ３ ）３ ）和铈－ 苯丙氨酸二元配合物（Ｃｅ（Ｐｈｅ）３ （ＮＯ３）３ ）与ＤＮＡ的相互作用。发现加入ＤＮＡ后稀土配合物的循环伏安曲线的峰电流值减小,当ＤＮＡ达到一定浓度时峰电流值不再减小。稀土配合物与ＤＮＡ的混合溶液体系中ＤＮＡ和稀土配合物的紫外光谱吸收峰均呈减色效应。     

Electrochemical Studies of Effect of Eu~(3 ) on Adenosine-5′-Diphosphate at Mercury Electrode

Ｎｕｃｌｅｉｃａｃｉｄｓｐｌａｙｉｍｐｏｒｔａｎｔｒｏｌｅｓｉｎｔｈｅｍｏｌｅｃｕｌａｒｂｉｏｌｏｇｙ．Ｔｈｅｅｎｏｒｍｏｕｓｇｒｏｗｔｈｉｎｔｈｅｎｕｃｌｅｉｃａｃｉｄｒｅｓｅａｒｃｈｈａｓｒｅｓｕｌｔｅｄｉｎａｎｅｅｄｆｏｒｍｅｔｈｏｄｓｓｕｉｔ...     

Anneal and Concentration Effect on PL Properties of Sol-Gel Derived Eu3+ Doped SiO2 Glass

Eu3 doped SiO2 nano-crystalline glasses were prepared by sol-gel method. The broad peak of XRD pattern indicates an amorphous SiO2 matrix. The affection of anneal time and anneal temperatures on photoluminescence (PL) properties of SiO2 glass under different Eu3 doping concentration were studied systematically. It is found that the optimized anneal time is about 3 h. The excitation spectra of 2% Eu3 doped SiO2 glass powder were measured under various anneal temperatures, and the optimized anneal temperature is observed around 700 ℃. The fluorescence-quenching effect can be observed in the emission spectra when the annealing temperature exceeds 700 ℃. The emission spectra of different molar ratio dopants were measured at an annealed temperature of 500 ℃, and the concentration-quenching phenomenon has also been observed in SiO2 glass powder when the molar ratio of Eu3 ion exceeds 3%. The result shows that the PL intensity approaches its maximum when the molar ratio of Eu3 ions in the sample is about 3%. In addition, a comparatively stronger emission spectrum at wavelength of 703 nm which is corresponding to the energy transition 5D0→7F4 of Eu ions is also obtained.     

Hydrothermal synthesis, crystal structure and luminescence of a europium complex with phenylmalonic acid and 1, 10-phenanthroline

A new complex Eu2（PA）6（phen）2 was prepared with hydrothermal reaction using EuCl3.6H2O, phenylmalonic acid （H2phma）, and 1, 10-phenanthroline （phen）, where PA was the decarboxylated product of HEphma, phenylacetate. The crystal structure of the title complex was determined with the X-ray diffraction. The title complex was a binuclear molecule with an inversion center. Each Eu^3＋ ion was nine-coordinated with two nitrogen atoms from one phen molecule and seven oxygen atoms from five PA ligands. The carboxylic groups were bonded to the Eu^3＋ ion in three modes, the chelating bidentate, the bridging bidentate, and the bridging-chelating tridentate. The complex emits intense red fluorescence under ultraviolet light. The luminescence peaks correspond to the characteristic emission 5D0→7FJ （J=0-4） transitions of the Eu^3＋ ion.     

Structure and Fluorescence Emission of Hetero-Nuclear Complexes of Europium-Lanthanum Nitrates with N,N′-Substituted Adipamide

Ｌｕｍｉｎｅｓｃｅｎｔｌａｎｔｈａｎｉｄｅｃｏｍｐｌｅｘｅｓｈａｖｅｂｅｅｎｉｎｔｅｎｓｉｖｅｌｙｓｔｕｄｉｅｄｆｏｒｔｈｅｉｒｗｉｄｅａｐｐｌｉｃａ ｔｉｏｎｓｉｎｐｈｏｔｏ ｄｅｖｉｃｅｓａｎｄｆｌｕｏｒｏ ａｎａｌｙｓｉｓ ,ｅｓ ｐｅｃｉａｌｌｙｉｎｔｈｅｕｓｅａｓｌｕｍｉｎｅｓｃｅｎｔｌａｂｅｌｓｉｎｆｌｕ ｏｒｏ ｉｍｍｕｎｏａｓｓａｙｆｉｅｌｄ[1] .Ｓｉｎｃｅｔｈｅｂａｃｋ ｇｒｏｕｎｄｌｕｍｉｎｅｓｃｅｎｃｅｏｆｂｉｏｌｏｇｉｃａｌｍａｔｅｒｉａｌｓｉｓｕｓｕａｌｌｙｓｈｏｒｔ ｌｉｖｅｄ…     

Luminescent characteristics of LiCaBO3：Eu^3＋ phosphor for white light emitting diode

LiCaBO3:Eu3+ phosphor was synthesized by high solid-state reaction method, and its luminescent characteristics were investigated. The emission and excitation spectra of LiCaBO3:Eu3+ phosphors exhibited that the phosphors could be effectively excited by near ultraviolet (400 nm) and blue (470 nm) light, and emitted red light. The effect of Eu3+ concentration on the emission spectrum of LiCaBO3:Eu3+ phos-phor was studied. The results showed that the emission intensity increased with increasing Eu3～ concentration, and then decreased because of concentration quenching. It reached the maximum at 3mol.% Eu3+, and the concentration self-quenching mechanism was the d-d interaction according to the Dexter theory. Under the conditions of charge compensator Li+, Na+ or K+ incorporated in LiCaBO3, the emission intensities of LiCaBO3:Eu3+ phosphor were enhanced.     

Fluorimetric study of the interaction between ATP and ciprofloxacin-Y3+ complex and its application

A simple spectrofluorimetric method was developed for determination of trace amount of adenosine disodium triphosphate(ATP).Under the optimum conditions,we studied the interaction between CIP-Y3+-ATP complex by using absorption and fluorescence spectra.It was observed that ATP remarkably enhanced the fluorescence intensity of the CIP-Y3+ complex at λem=415 nm and the enhanced fluorescence intensity of Y3+ ion remained proportional to the concentration of ATP.The developed method was successfully applied for...     

Synthesis, crystal structure, and fluorescence of two dimeric europium(Ⅲ) complexes with 2-(trifluoromethyl)benzoate

Two complexes [Eu2(2-TFMBA)6(2,2'-bipy)2].2H2O (1) and Eu2(2-TFMBA)6(1,10-phen)2 (2) (2-TFMBA=2-(Trifluoromethyl) benzoate; 2,2'-bipy=2,2'-bipyridine; 1,10-phen=1,10-phenanthroline) were synthesized by solvent method and determined by X-ray diffrac-tion analysis. Complex 1 crystallizes in monoclinic system with space group P21/c, whereas complex 2 crystallizes in triclinic system with space group P-1. Both are binuclear molecules with an inversion center. In complex 1, two center Eu3+ ions are linked together by four 2-TFMBA ligands in bidentate-bridging mode. Each Eu3+ion is eight-coordinated with six O atoms from five 2-TFMBA ligands and two N atoms from one 2,2'-bipy molecule. In complex 2, two center Eu3+ ions are linked together by four 2-TFMBA ligands in two modes, namely, bidentate-bridging and tridentate-bridging. Each Eu3+ ion is nine-coordinated with seven O atoms from five 2-TFMBA ligands and two N atoms from one 1,10-phen molecule. The two complexes both exhibited strong red fluorescence under ultraviolet light, and the 5D0→7Fj (j=0-4) transition emissions of Eu3+ ion were observed in their emission spectra.     

Effect of gadolinium incorporation on optical characteristics of YNbO_4：Eu~（3＋） phosphors for lamp applications

Eu3+-doped (Y,Gd)NbO4 phosphor was synthesized by solid-state reaction for possible application in cold cathode fluorescent lamps. A broad absorption band with peak maximum at 272 nm was observed which was due to the charge transfer between Eu3+ ions and neighboring oxygen anions. A deep red emission at the peak wavelength of 612 nm was observed which could be attributed to the 5D0→7F2 transition in Eu3+ ions. The highest luminance for Y1-x-yGdyNbO4:Eux3+ under 254 nm excitation was achieved at Eu3+ concentration of 18 mol.% (x=0.18) and Gd3+ concentration of 8.2 mol.% (y=0.082). The luminance of Y0.738Gd0.082NbO4:Eu3+0.18 was higher than that of a typical commercial phosphor Y2O3:Eu3+ and the CIE chromaticity coordinate was (0.6490, 0.3506), which was deeper than that of Y2O3:Eu3+. The particle size of the synthesized phosphors was controlled by the NaCl flux and particle size as high as 8 μm with uniform size distribution of particles was obtained.     

溶胶-凝胶法制备Ca3Al2O6：Eu3+红色荧光粉及其发光性能

采用溶胶-凝胶法合成Ca3Al2O6：Eu3+红色荧光粉,通过XRD、SEM、荧光光谱分别对样品的结构、形貌以及发光性能进行表征,讨论煅烧温度、Eu3+掺杂浓度以及电荷补偿剂对样品发光性能的影响.结果表明：实验所得样品的结构与Ca3Al2O6相同,Eu3+掺杂并没有改变其晶体结构.合成的荧光粉在394 nm近紫外光激发下发出615 nm明亮的红光.样品的红光强度随着煅烧温度的升高先增加后减弱,最佳烧结温度为1200℃.同样红光强度也随着Eu3+掺杂浓度的增加先增加后减弱,最佳Eu3+掺杂浓度为4%（摩尔分数）.加入电荷补偿剂后样品的发光强度均增强,其中加入K+后发光增强的效果最显著.该铝酸盐红色荧光粉性质稳定,在白光LED近紫外芯片激发中具有潜在的应用.     

Crystal Structure and Luminescence Property of Lanthanide Complexes with 2-Fluorobenzoic Acid and 2,2''-Bipyridine

The two compounds of [Ln(2-FBA)3·2,2'-bpy]2 (2-FBA=2-fluorobenzoato, 2,2'-bpy=2,2'-bipyridine, Ln=Eu(1), Dy(2)) were synthesized and their structures were determined by X-ray diffraction method. Crystallized complexes 1 and 2 are isomorphous, monoclinic system with P21/n space group. The two complexes are binuclear molecule with an inversion center. The two lanthanide ions are linked by four bridged 2-FBA ligands and each lanthanide ion is further bonded to one chelated bidentate 2-FBA ligand and one 2,2'-bipyridine molecule. The coordination number of metal ion is eight. The europium complex exhibits strong red fluorescence. 5D0→7Fj (j= 1～4) transition emission of Eu3 ion was observed.     

Synthesis,crystal structure and fluorescence property of 1-D europium complex with 2,3-difluorobenzoate

A new chain europium complex [Eu(2,3-DFBA)3·(H2O)2]n(2,3-DFBA=2,3-difluorobenzoate) was synthesized by solvent method.X-ray single-crystal diffraction analysis revealed that Eu3+ ions were linked through 2,3-DFBA groups via alternate bidentate-bridging and tridentate chelating-bridging coordination modes to form a one-dimensional(1-D) polymeric chain.Each Eu3+ ion is eight-coordinated by six O atoms of five 2,3-DFBA ligands and two water molecules.The abundant hydrogen bonds between chains resulted in a two...     

Luminescence Characteristic of a New Novel Coprecipitate Rare Earth Complexes

Organicelectroluminescence (OEL)hasbeenex tensivelystudiedbecauseoftheirpotentialapplicationinflatpaneldisplayssincethefirsttwo layerOELde vicewithhighefficiencyandluminancewasfabricatedin 1987[1～ 3] .Rareearth (RE)metalcomplexeshavesomegoodcharacteristics ,suchasextremelynarrowe missionbandsandhighinternalquantumefficiencies ,whicharesuitableforuseastheemissionmaterialsinOEL[4 ] .Tb3+complexwasfirstintroducedintoOELdevices ,andsharpgreenemissionfromTb3+ionhasbeenobserved[5] .Sincethen …     

Synthesis and photoluminescence of a dendritic europium complex with carbazole moieties

A novel dendritic europium complex containing grafted carbazole units as functional peripheries was synthesized and characterized. The Foerster energy transfer from the peripheries of carbazole units to β-diketonate as well as from the hgands to the central Eu（Ⅲ） ions in the complex was demonstrated. Under the excitation of carbazole units and β-diketonate, characteristic red emission peaks at 612 nm with four shoulders due to the Eu（Ⅲ） ion transition of 5^D0→7^FJ （J=0-4） were observed for the complex.     

Preparation and Fluorescence Properties of Polymethyl Methacrylate Resin Incorporated with Sodium Tris （Pyridine Dicarboxylato）Europate

Based on the strong fluorescence and the highly thermal stability of sodium tris (pyridine dicarboxylato)eruopate(Na3Eu(DPA)3),polymethyl methacrylate(PMMA)composite material incorporated with the complex,PMMA:Na3Eu(DPA)3,was prepared at 250℃，The fluorescence behavior of PMMA:Na3Eu(DPA)3material was examined,The results show that the composite material keeps the luminescent characteristics of the Eu^3 chelate after PMMA is incorporated with Na3Eu(PDA)3,and strong orange-red emission of the composite wsa observed.The fluorescence intensity of the composite material increases with the increase of the weight ratio of Na3Eu(PDA)3to PMMA,but the relationship is not linear.     

Triboluminescence of A New Europate Complex

A new europium (Ⅲ)complex Eu(HFNH)3Phen (HFNH: 4, 4, 5, 5, 6, 6, 6-heptafluoro-l-(2-naphthyl)hexane-1,3-dione ; phen : 1, 10-phenanthroline) was synthesized and its tribolumineseent phenomenon was observed. Photoluminescence and tfiboluminescence spectra were successfidly determined. The most intense tfiboluminescent emission originates from the transition of the central Eu^3 ion from ^5D0 level to ^7F2 level. The tribolunlinescent spectrum is basically similar to that of photoluminescence, which correlates with the disorders of F atoms.     

Influence of bidentate structure of an aryl phosphine oxide ligand on photophysical properties of its Eu~Ⅲ complex

The bidentate phosphine oxide ligand 1,8-bis(diphenylphosphino) naphthalene oxide (NAPO) and its EuⅢ complex 1 Eu(TTA)3(NAPO) (TTA=2-thenoyltrifluoroacetonate) were chosen to study the effect of bidentate phosphine oxide ligand on the photophysical properties of the corresponding complex. The intramolecular energy transfer processes of 1 were studied. The investigation showed that with bidentate structure NAPO could suppress solvent-induced quenching by enforcing the ligand-ligand interaction and the rigidity of the complex. Contrasted with the monodentate triphenylphosphine oxide (TPPO), NAPO had a higher first triplet excited energy level (T1) and a lower first singlet excited energy level (S1), which fitted to the corresponding excited energy levels of anion ligand TTA much more and supported more efficient singlet and triplet energy transfer in its EuIII complex.     

Encapsulation of Eu(TTA)3 into MCM-41 Mesoporous Molecular Sieve by Sol-Gel Method

Ｔｈｅｄｅｓｉｒａｂｌｅｌｕｍｉｎｅｓｃｅｎｃｅｃｈａｒａｃｔｅｒｉｓ ｔｉｃｓｏｆｓｏｍｅｌａｎｔｈａｎｉｄｅｉｏｎｓｂａｓｅｄｏｎｔｈｅｉｎｔｒａ ｆ ｏｒｂｉｔａｌｔｒａｎｓｉｔｉｏｎｓｈａｖｅｒｅｃｅｉｖｅｄｍｕｃｈａｔｔｅｎ ｔｉｏｎ.Ｒａｒｅｅａｒｔｈｃｏｍｐｌｅｘｅｓ,ｅｓｐｅｃｉａｌｌｙｔｈｏｓｅｃｏｎｔａｉｎｉｎｇＥｕ3 ａｎｄＴｂ3 ,ｏｆｔｅｎｅｘｈｉｂｉｔｇｏｏｄｌｕｍｉｎｅｓｃｅｎｃｅｏｗｉｎｇｔｏｔｈｅｓｔｒｏｎｇａｂｓｏｒｐｔｉｏｎｏｆｔｈｅｏｒｇａｎｉｃｌｉｇａｎｄｓａｎｄ…     

Photophysical properties of a new ternary europium complex with 2-thenoyltrifluoroacetone and 5-nitro-1,10-phenanthroline

A ligand, 5-nitro-1,10-phenanthroline (phenNO2), was synthesized. Its Eu(III) complex with 2-thenoyltrifluoroacetone (HTTA) was prepared and characterized by elemental analysis, IR and 1H NMR spectra. The photophysical properties of the complex were studied in detail by using UV, luminescence spectra, luminescence lifetime and quantum yield. The complex exhibited nearly monochromatic red emission at 612 nm, a remarkable luminescence quantum yield at room temperature (36.0%) upon ligand excitation and a long 5D0 lifetime (458 μs), which indicated that the ligand phenNO2 could sensitize the luminescence of Eu(III) ion efficiently.     

Crystal Structure and Luminescence of 1,10-Phenanthroline-tris (4-methoxybenzoato)Europium

ＣｒｙｓｔａｌＳｔｒｕｃｔｕｒｅａｎｄＬｕｍｉｎｅｓｃｅｎｃｅｏｆ１，１０Ｐｈｅｎａｎｔｈｒｏｌｉｎｅｔｒｉｓ（４ｍｅｔｈｏｘｙｂｅｎｚｏａｔｏ）ＥｕｒｏｐｉｕｍＷａｎｇＲｕｉｆｅｎ（王瑞芬），ＬｉＬｉｎｓｈｕ（李林书）（Ｄｅｐａｒｔｍｅｎｔ...