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K. N. Mehrotra M. Chauhan R. K. Shukla 《Journal of the American Oil Chemists' Society》1996,73(7):897-902
The ultrasonic velocity and density measurements of europium soaps in a mixture of benzene and methanol (3:2, vol/vol) were
used to evaluate various acoustic parameters and molar volume and to determine the critical micelle concentration. The results
showed that the ultrasonic velocity, specific acoustic impedance, molar sound velocity, and molar compressibility increase,
and intermolecular free length, adiabatic Compressibility, and relative association decrease with increasing concentration
and chainlength of the soap. The results were interpreted in terms of soap-solvent interaction. 相似文献
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YANG Shuijin YUAN Liangjie and SUN Jutang) Department of Chemistry Environmental Engineering Hubei Normal University Huangshi China) College of Chemistry Molecular Sciences Wuhan University Wuhan China 《稀有金属(英文版)》2003,22(2)
The Eu3+-doped Na24As2W22O83 phosphor has been prepared by solid state reaction from Na3AsO412H2O, Na2WO4 2H2O and WO3, and characterized by elemental analysis, infrared spectroscopy and powder X-ray diffractometry. According to the measurements with X-ray diffraction, this material belongs to orthorhombic system with its lattice constants: a = 1.4750 nm, b = 1.1944 nm, c = 1.1062 nm, it is consistent with space group D24-P212121 (No.19). The emission and excitation spectra were measured. The luminescent properties of Eu3+-doped Na24As2W22O83 and mechanism of energy transfer were discussed. 相似文献
6.
HAN Yingchao LI Shipu Ingo Bauer WANG Xinyu WANG Youfa 《武汉理工大学学报(材料科学英文版)》2005,20(B12):203-205
The nanocrystalline Eu^3+ doped calcium phosphate was prepared by calcining precursors, which were got by precipitation method combined with ultrasound treatment and some polysaccharide. The existence of Eu^3+ inhibited the reaction of Na^+ ion and SO4^2- radical with apatite and resulted in the transformation of HAP to β- TCP by replacing the calcium ions. The strongest excitation peak was at 393 nm, and other lower peaks were at 361 nm, 375 nm, 381 nm, 418nm. The strongest emission spectrum appeared at about 618nm. The emission peak (579 nm) showed that Eu^3+ ions distributed on Ca^2+ sites of the apatitic structure. 相似文献
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1Introduction Hydroxyapatite(Ca10(PO4)6(OH)2)isanimportant biomaterialthatiswidelyusedassubstituteorfillingma terialforscleroustissuesduetoitsgoodbiocompatibility andosteoconductivity[1,2].Inordertoinvestigatethein teractionsbetweenHAPnanoparticleswithana… 相似文献
8.
铕三元配合物的合成、表征及其光致发光性能 总被引:1,自引:0,他引:1
以苯甲酸、邻苯二甲酸、间苯二甲酸、水杨酸、丙烯酸、甲基丙烯酸、α—噻吩基三氟甲酰丙酮为第一配体,二安替比林甲烷,三正辛基氧化膦、2,2’-联吡啶、邻菲咯啉及邻菲咯啉N-氧化物为第二配体,合成了系列铕三元配合物。经元素分析确定了它们的组成;研究了它们的紫外吸收光谱、红外吸收光谱及荧光光谱。紫外光谱的研究表明,配合物的紫外吸收主要表现为配体的吸收,但是吸收峰的位置发生了移动;红外光谱的研究表明,配合物的红外光谱不同于自由配体的红外光谱,在400~500 cm-1出现了吸收峰,这是Eu-O的伸缩振动峰;荧光光谱的研究表明,第二配体的加入可以显著提高配合物的荧光性能。 相似文献
9.
用循环伏安法研究了CO在Pt/C,Pt/Eu3 /C电极上的氧化,发现吸附稀土Eu3 后。电极表面对CO的吸附明显减弱,吸附量减少.CO在电极表面的氧化过电位减小,CO的起始氧化电位负移130mV,Eu3 在电极表面的吸附对CO的氧化有电催化作用. 相似文献
10.
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)°,C66H40N4O12Cl6Eu2, Mr=1597.64, V=1.5533(2) nm3, Z=1, Dc=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 Rint=0.0776.The crystal consists of binuclear molecules of the title compound. Each Eu3 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. 相似文献