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Luminescent micelles were prepared through the self-assembly of poly(ethylene glycol)-block-poly(4-vinylpyridine) (PEG114-b-P4VP61) and Europium(III) (Eu(III)), with P4VP/Eu(III) as the core, and PEG as the corona. 1,10-phenanthroline (Phen) was assembled
into the core of the micelles to sensitize the luminescence. The presence of Phen results into the increasing of apparent
average hydrodynamic diameters (Dhapp {\hbox{D}}_{\rm{h}}^{\rm{app}} ) of the micelles. All Eu(III)-containing micelles emitted the characteristic fluorescence of Eu(III). The intensity of luminescence
increased with the presence and the increasing quantity of Phen in the complex micelles due to the effective energy transferring
of Phen in the “antenna effect”. 相似文献
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The solubility and the critical relative humidity (H(cr)) of 14 drugs and inorganic salts were determined, the relationship between the H(cr) and the solubility was explored theoretically, and the H(cr) was calculated in the light of Raoult's law and Pitzer ion interaction model from their solubility. The results indicate that the H(cr) values calculated by Raoult's law in high humidity (H(cr)>80%) and by Pitzer ion interaction model in low humidity (H(cr)<80%) are comparable to the measured ones. 相似文献
24.
近年来,对天然气的综合利用已逐渐为人们所重视。甲烷氧化偶联制乙烯、乙烷这一新课题受到催化工作者愈来愈多的关注[1~5]。本工作初步探讨了Li-Ln-MgO三元氧化物催化剂对甲烷氧化偶联反应的催化性能。添加稀土元素可使C2的选择性、单收明显提高。本催化剂体系制备简单、原料便宜,值得进一步开发研究。 相似文献
25.
全息光存储以其高密度、大容量、高速并行数据存取而成为光存储领域的一个重要研究方向。生物光致变色材料———菌紫质是一种新型可擦重写全息记录介质。实验证明了使用菌紫质薄膜进行角度复用和偏振复用全息存储的可行性。利用菌紫质的光致变色特性,采用90°角度复用全息存储光路,在BR-D96N薄膜样品同一位置上实现了6幅全息图存储,并分别读出了无串扰的再现像。利用菌紫质薄膜的光致各向异性进行了偏振复用全息存储,在BR-D96N薄膜样品的同一位置上存储了两幅正交偏振光记录的图像,用原参考光再现和偏振片选择,可分别读出这两幅图像。 相似文献
26.
Wei Y Guo X Shuang S Dong C Sun X Wong M 《Journal of photochemistry and photobiology. B, Biology》2005,81(3):190-194
Novel dimeric capsules are generated from the noncovalent assembly of 5, 10, 15, 20-tetrakis(4-N-ethylpyridiniurmyl)prophyrin (TEPyP) and tetracarboxyl-phenyl calix[4]arene. The self-assembly system was investigated based on UV-Vis absorption and fluorescent spectra. The factors affecting the interaction process including pH and concentration were examined in detail. The association constants between TEPyP and calix[4]arene were determined by the nonlinear least squares fit. The results showed that the basic medium is favourable to the interaction and electrostatic interaction was determinate in the processes of self-assembly process. The related mechanism was discussed. 相似文献
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渐变折射率光波导的精确分析 总被引:2,自引:5,他引:2
本文利用转移矩阵理论和等效衰减系数的概念,导出了渐变折射率光波导的色散方程,数值计算的结果,赢余方程的精度优于目前存在的所有近似方法。 相似文献
30.
Lijun Jia Huaiwu Zhang Jun Luo Yingli Liu Qiye Wen 《Journal of magnetism and magnetic materials》2010,322(14):1934-1938
MgO was introduced into low-temperature sintered Z-type hexaferrites in order to improve their high-frequency electromagnetic properties. In the doped samples the major Z-type phase coexists with a small amount of W-type magnetoplumbite phase. The addition of MgO causes a decrease of the average grain size and an increase of the magnetocrystalline anisotropy (K1) and the saturation magnetization (Ms) with the increment of K1 being larger than that of Ms. These factors result in a reduce of the initial permeability. Also, the samples with MgO additive exhibit higher Q-factor and dc resistivity. Furthermore, the introduction of MgO can decrease the dielectric constant and improve the dielectric loss tangent of the samples by reducing the electronic transition in octahedral site (B-site) between Fe2+ and Fe3+ ions. 相似文献