掺钕聚甲基丙烯酸甲酯的光学特性

研究了制备的掺钕螯合物Nd(DBM)3Phen材料的吸收光谱、激发光谱、荧光光谱,应用Judd-Ofelt理论计算了该材料的强度参量．分析了钕离子激发态4F3／2的辐射寿命(631 μs)和4F3／2→4IJ′跃迁的受激发射截面和荧光分支比．     

第二配体对Sm(DBM)3掺杂的PMMA样品发光的影响

分别使用phen（1,10-邻菲咯啉）、TOPO（三正辛基氧化磷）、TPPO（三苯基氧化磷）作为第二配体与Sm（DBM）3（DBM：二苯甲酰甲烷）相互作用,合成了相应的配合物,然后分别将其掺入MMA中,进行聚合得到了固体样品。测量了不同第二配体样品及无第二配体样品的激发和发射光谱,对谱峰做了指认。发射谱中主要发射峰均为Sm^3＋的特征发射,有机配体的发光带很弱,说明从有机配体到稀土发光中心的能量传递非常有效。监测Sm^3＋离子644nm发射峰（^4G5/2→^6H9/2）测量了样品的激发光谱。结果显示,第二配体的加入改变了有机配体的能级结构,激发边出现明显的移动,同时紫外区的激发效率发生了变化,对发光产生了显著的影响。还测量了上述样品中Sm^3＋的^4G5/2能级的发光衰减曲线,拟合出该能级的跃迁寿命,针对不同第二配体的情况进行了比较分析。实验结果表明,第二配体的共轭性和化学键匹配对发光强度影响很大,在我们的结果中,第二配体为TPPO时发光效率最高。     

含铕配合物荧光纳米纤维的制备及光学性质的研究

通过静电纺丝技术,将发光良好的稀土配合物Eu(DBM)₃·H₂O和Eu(DBM)₄·CPC纳米微粒复合到水溶性的聚乙烯基吡咯烷酮中,制备了具有稀土铕离子红色特性荧光的聚合物纳米纤维。通过对稀土配合物以及聚合物纳米纤维样品扫描电镜和透射电镜的测试,发现当稀土配合物复合到聚合物纳米纤维中后,由于与聚乙烯基吡咯烷酮乙醇溶解性良好,其微观结构发生了变化,得到了50～100 nm左右的比较均匀的线状结构。同时,通过对稀土配合物以及聚合物纳米纤维样品的荧光激发、发射光谱及荧光寿命进行研究,表明稀土配合物在聚合物纳米纤维中比其在粉末状有更高的发光强度及更长的荧光寿命,其原因在于高分子纳米纤维为稀土配合物提供了较稳定的化学环境。     

Eu(DBM)3纳米微晶的低频喇曼光谱

The fractal property and low frequency Raman scattering of Eu(DBM)3 nanosized microcrystals were investigated. The influence of the fractal structure of Eu(DBM)3 non-crystalline solids on low frequency scattering was studied. It was found that vibrational excitations on the fractal are localized and can be described in terms of fractions. It was shown that reduced Raman scattering intensity is of a power law dependence of the vibrational frequencies for all samples. The fractal and spectral dimension were also determined, we found that our experimental value was in fair agreement with the theoretical one.     

含Eu(DBM)_3·H_2O纳米微晶的光学树脂的制备及性能研究

稀土β二酮的配合物因其具有Antenna效应,发光强度明显增强;而且它的激光性质也被证实[1] ,是应用价值极大的配合物.稀土配合物与高分子的复合,获得了兼具二者优良性能的功能材料,有很好的应用前景.通常二者的复合多采用直接掺杂、机械共混和熔融等方法.但由于二者的相容性较差,并且存在着浓度淬灭现象,使获得高稀土含量、分散均匀的聚合物发光材料非常困难.以往,杨柏小组分别采用直接掺杂和原位复合的方法制备了含稀土配合物的光学树脂[2 ,3 ] ,但稀土配合物含量受到限制.本文在文献[4,5 ]的基础上,采用化学沉淀的方法,制备了30～30 0nmEu…     

二溴对甲偶氮磺光度法测定锌合金中微量铅

研究了新试剂二溴对甲偶氮磺与铅的显色反应,建立了直接测定锌合金中微量铅的光度分析方法。在硝酸介质中,二溴对甲偶氮磺与铅发生灵敏的显色反应,生成1∶2的蓝色配合物。铅配合物的最大吸收峰位于630nm,表观摩尔吸光系数和Sandell灵敏度分别为1.07×105L·mol-1·cm-1和1.94ng·cm-2;显色反应在常温下(<30℃)立即完成,而配合物及试剂空白的吸光度在24h内基本保持不变;铅在0～90μg/25ml范围内符合比耳定律;显色反应有良好的选择性,主要共存金属离子均有较大的允许量,可用于锌合金中微量铅的直接测定。     

Novel pH responsive luminescent poly(oxyethylene phosphate) tris(β-diketonate) europium (III) complexes

The paper reports on the dependence of the absorbance and luminescent intensity from pH of novel poly(oxyethylene phosphate) tris(β-diketonate) europium (III) complexes. The photophysical data obtained allow some preliminary assumptions about the nature of this phenomenon. Increase in luminescent efficiency is a consequence of enhanced efficiency of energy transfer caused by structural changes in complexes after water deprotonation. Remarkable change has been observed in photophysical properties of the polymer complexes by studying the fluorescent emission and excitation spectra and absorption recorded at various pH both in solution and in the solid state. Some of the complexes derivative of the dibenzoylmethane (DBM) show more than hundred times increase in the luminescence after alkalization. The pH value, at which the maximum luminescent efficiency appears, depends on the type of the fourth ligand. The difference between luminescent efficiency of the complexes in alkaline and neutral environment depends on the β-diketonate ligands and on polymer type as well.      

Luminescence and crystal-field fitting of two optical isomeric complexes of europium

FT-IR and Raman vibrational spectra and electronic emission spectra have been recorded for enantiomers of europium complexes with DBM: dibenzoylmethanate 1,2, and TTFA: 2-thenoyltrifluoroacetonate 3,4, employing the chiral ligands L_SS(+)- and L_RR(-)-4,5-pinene bipyridine. Contrary to the previously published X-ray data, where geometrical differences were stated to occur for particular enantiomers, the vibrational (and the emission) spectra of the individual optical isomers of a complex are not distinguishable. Using excitation into the Eu³⁺⁵D₂ multiplet term, the emission intensity is weak from ⁵D₁, whereas a complex structure is observed for the ⁵D₀→⁷F_J transitions. Features in the vibronic sidebands exhibit similar derived vibrational energies to those observed in the Raman spectra. Fittings of 25 4f⁶ crystal-field energy levels of 2 and 4 have been attempted with some approximations concerning the local Eu³⁺ environments. The ⁵D₀ emission lifetimes are monoexponential and are 0.5 (1,2) and 0.9 ms (3,4) at room temperature.     

Eu（DBM）3纳米微晶的低频喇曼光谱

低频喇曼（LFR）光谱技术广泛应用于无序体系的结构性质研究，它能提供有关微粒的非弹性振动、量子尺寸效应以及分形体的光散射性质等方面的信息［‘一句.尤其是通过LFR光谱的研究，可以确定分形体振动（频率为叫激发的光谱线数已用于描述分形结构的局域振动量子一分形子的态密度：N（川。0‘’‘，又称之为分形干线教，是联系“几何结构”与“动力学行为”的重要参数.对它进行深入而广泛地研究，将有可能为更深入地认识无序材料的物理、化学性质带来重大的突破，因而引起人们的极大兴趣.其研究工作主要集中于非晶态的硅溶胶和玻璃体系［…     

光泵浦双反射带半导体激光器的热效应有限元分析

给出了808 nm/980 nm双反射带布拉格反射镜的反射谱线,建立了光泵浦双反射带半导体激光器件的热学模型及其内部热载荷分布形式,运用有限元分析方法,详细分析了双反射带光泵浦半导体激光器件的热学特性。结果表明,对于激射光反射率为99.96%的单反射带和双反射带布拉格反射镜结构的垂直外腔面发射半导体激光器件,前者的散热性能较好,而后者的最大温升明显低于前者。本文的分析结果可为半导体激光器件的结构优化和实验研究提供理论参考。