Abstracts from the 8th International Conference on cGMP Generators, Effectors and Therapeutic Implications

This work was supported by a restricted research grant of Bayer AG

Synthesis And Photoluminescence Properties Of Eu\u3csup\u3e3+\u3c/sup\u3e-Doped Zro2 Hollow Spheres

ZrO2:Eu3+ hollow spheres were successfully fabricated with the resin microspheres as the template. The sample characterizations were carried out by means of x-ray diffraction (XRD), scanning electron microscope (SEM), and photoluminescence spectra. XRD results revealed that Eu3+-doped samples were pure t-ZrO2 phase after being calcined at 873 K. SEM results exhibited that this Eu3+ doped ZrO2 was hollow spheres; the diameter and thickness of which were about 450 and 50 nm, respectively. Upon excitation at 394 nm, the orange-red emission bands at the wave length longer than 570 nm were from 5D0 → 7FJ (J = 1, 2) transitions. The asymmetry ratio of (5D0 → 7F2)/(5D0 → 7F1) intensity is about 1.61, 1.26, 1.42, 1.42, 1.40, and 1.38 for the Eu3+ concentration 0.4, 0.7, 1.0, 1.5, 2.0, and 2.5 mol%, respectively. These values suggest that the asymmetry ratio of Eu3+ ions is independent of the doping concentration. The optimal doping concentration of Eu3+ ions in ZrO2 is 1.5 mol%. According to Dexter\u27s theory, the critical distance between Eu3+ ions for energy transfer was determined to be 16 Å

Photoluminescence Properties Of Tb\u3csup\u3e3+\u3c/sup\u3e-Doped Stalk-Like Al2O3

Uniform Al2O3 : Tb3+ samples were successfully fabricated via a hydrothermal method and subsequent thermal decomposition of Tb3+ doped precursors. Scanning electron microscopy results showed Tb3+-doped Al2O3 was stalk-like with an average length about 1.5 μm. Photoluminescence spectra indicated that the 5D4 → 7F5 (545 nm) electric dipole transition was most intense upon excitation at 227 nm. It is shown that 1.5 mol.% doping concentration of Tb3+ ions in Al2O3 : Tb3+ is optimum. According to Dexter\u27s theory, the critical distance between Tb3+ ions in Al2O3 for energy transfer was determined to be 14 Å

Synthesis And Photoluminescence Properties Of Tb\u3csup\u3e3+\u3c/sup\u3e Doped Zro2 Hollow Spheres

ZrO2:Tb3+ hollow spheres were successfully fabricated with the resin microspheres as the template. The sample characterizations were carried out by means of X-ray diffraction (XRD), scanning electron microscope (SEM) and photoluminescence (PL) spectra. XRD results revealed Tb3+ doped samples were pure t-ZrO2 phase after being calcined at 873 K. SEM results exhibited these Tb3+ doped ZrO2 was hollow spheres, the diameter and thickness of which were about 450 nm and 50 nm, respectively. The PL spectra indicate that the 5D4 →7F5 (545 nm) electric dipole transition is the most intensive when excited at 235 nm. It is shown that the 2.0 mol% of doping concentration of Tb3+ ions in t-ZrO2:Tb3+ is optimum. According to Dexter\u27s theory, the critical distance between Tb3+ ions for energy transfer was determined to be 15 Å. It is found that the decay curves follow the single-exponential decay. The convenient synthetic procedure, excellent reproducibility, clean reactions, high yield, and fine quality of products in the work make the present route attractive and significant

シンポジウム グローバリゼーションと現代歴史学 シンポジウムへの経過

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