Biomedical subjects

Xiao-liang Yang

Publications and source records attributed to Xiao-liang Yang.

4 recordsLinked to original sources

PubMed2005

[Study on red up-conversion luminescence of fluoride glasses doped with Er3+, Yb3+ and Tm3+].

When the quality of Er2O3 is 10 times the former, the authors found that its character of up-conversion luminescence is distinct. Then the authors studied the luminescence system of Es3+ /Tm3+, Er3+ /Er3+ and Er3+ /Yb3+ /Tm3+ and their character of upconversion and fluorescence spectrum at 980 nm. In addition, the authors studied the relation between the three systems and the consistency of Er2O3. The authors found that the intensity of green and red light changed with the consistence of Er3+ in the experiment. It's the consistence of Er3+ that is the most causative. The chance is equal for each lanthanonion that makes up the luminescence system in the uniformity matter. With the distance between each pair of lanthanonions in the luminescence system is changed, the luminescence system and the color of the up-conversion luminescence also changed.

Europium↗

PubMed2003

[Multiply upconversion emission in oxyfluoride ceramics].

Oxyfluoride ceramics with the host composition of SiO2 and PbF2 have been prepared. X-ray diffraction analysis of the ceramics revealed that fluoride type beta-PbF2 solid solution regions are precipitated in the glass matrix. Rare earth ions in the beta-PbF2 solid solution show highly efficient upconversion performance due to the very small multi-phonon relaxation rates. Eight upconversion emission bands whose central wavelength are 846, 803, 665, 549, 523, 487, 456 and 411 nm have been observed when the sample was excited with 930 nm diode light. Four possible energy transfer processes between Er3+ and Yb3+ cause the electronic population of high energy level of Er3+ and realize the abound upconversion luminescence bands.

Ceramics↗

PubMed2003

[Upconversion luminescence in Ho3+ doped fluoride thin film with excitation red laser].

Ho3+ doped fluoride thin film was deposited on common glass matrix by low energy pulse laser (532 nm, quadratic harmonics of Nd: YAG laser). Red and green upconversion luminescences with central wavelength of 770 and 540 nm have been observed through Japan R-500 spectrometer with excitation of 632.8 nm He-Ne laser. These upconverted emissions are ascribed to transitions of 5S2-->5I7, 5F4-->5I7 and 5S2-->5I8 and they are realized by two step absorption of Ho3+ ions and energy transfer among Ho3+ ions.

Chemical Phenomena↗

PubMed2002

[The study of up-conversion fluorescence in Er3+:Yb3+ co-doped oxy-fluoride glasses].

Er3+:Yb3+ co-doped oxy-fluoride glasses with composition of (50-x) GeO2.PbF2.WO3.(6 + x) CdF2.1.4Yb2O3.0.6Er2O3 (x = 10,20,30) were prepared. Their up-conversion fluorescence characteristics were investigated under excitation of 930 nm diode laser. Three strong fluorescence bands of Er3+ whose central wavelength lie in 543, 550 and 655 nm have been observed. The maximum phonon energy is obtained by measuring anti-stokes Raman shifts of the samples, and the up-conversion mechanism is briefly discussed. The influences of host materials composition on up-conversion efficiency are also discussed adopting the average electronegative difference and the cationic field strength of the host. It is found that relative small average electronegative difference and large cationic field strength of host benefit to energy up-conversion.

Cadmium↗