LUMINESCENCE AND ENERGY-TRANSFER IN GDP5O14-EU3+,SM3+ SINGLE-CRYSTALS

In this paper we report on the luminescence and energy transfer in GdP4O14:Eu3+,Sm3+ (GdPP:Eu,Sm) in single crystals grown by the hydrothermal method. The room temperature excitation, emission, absorption and IR spectra of the crystals have been measured and analysed. The energy transfer from Gd3+ and Sm3+ to Eu3+ ions in GPP:Eu,Sm crystals is also discussed.

LUMINESCENCE OF BI(3+) AND THE ENERGY-TRANSFER FROM BI(3+) TO R(3+) (R=EU,DY,SM,TB) IN ALKALINE-EARTH BORATES

At room temperature, the Bi3+ ion shows broad band characters of its luminescence in Ca2B2O5, M3B2O6 ( M=Ca,Sr ) and SrB4O7. The maxima of the Bi3+ S-1(0)-->P-3(1) absorption bands are located in the range of 240-300nm, but the energy variation of the corresponding P-3(1)-->S-1(0) emissions is very large. The maxima of these emission bands change from 350nm in Ca3B2O6;Bi3+ to 586nm in SrB4O7:Bi3+. The Stokes shift of the Bi3+ luminescence increases from 6118 cm-1, in Ca2B2O5:Bi3+, to 24439 cm-1, in SrB4O7:Bi3+. The emission intensity of the Bi3+ luminescence increases with the decreasing Stokes shift. It has been found that in Ca2B2O5, the Bi3+ ion could transfer its excitation energy to the R3+ ions ( R=Eu, Dy, Sm, Tb ) , but in, Ca3B2O6 and Sr3B2O6, only Bi3+-->Eu3+ was observed. No energy transfer from Bi3+ to R3+ was detected in SrB4O7.

INVESTIGATIONS ON THE ENERGY-TRANSFER OF EXCITED PARTICLE COLLISION WITH DOUBLE LASER LINES FOR EXCITATION OF LA(I)

Generally speaking, productions of thermally-assisted and stepwise fluorescence are the consequence of energy transfer caused by particle collision. In some circumstances, energy transfer caused by particle collision is considerably intense. We have ever used the fluorescence produced by energy transfer of particle collision to measure the branching ratios in the atomic transitions and acquired good results. To our knowledge, the systematic in

Comparative studies on the efficiency of energy transfer of two R-phycoerythrin-C-phycocyanin conjugates constructed from sodium periodate and glutaraldehyde respectively

The C-phycocyanin and the R-phycoerythrin were purified from the blue-green alga Spirulina platensis and red alga Polysiphonia urceolata respectively. Both sodium periodate and glutaraldehyde are effective coupling agents being capable of constructing the R-phycoerythrin-C-phycocyanin conjugate, which was also called phycobiliproteins energy transfer model. The two artificial conjugates constructed with different methods were purified by Sephadex G-200 chromatography respectively. Spectra analysis indicated that energy transfer occurred in the two conjugates. The conjugate with sodium periodate had the higher efficiency of energy transfer than that with glutaraldehyde conjugate.