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21.
S. F. Shaukat Ph. D. Ya-Ming Dong Ph. D. M. Hussain R. Farooq Guang-Yuan Li 《上海大学学报(英文版)》2002,6(1):45-49
Up-conversion processes for the blue, green and red emissions were found two-photon phenomenon, known as the cooperative phenomenon.
This phenomenon was assisted by Nd3+ → Yb3+ → Ho3+ energy transfer. The strong green emission due to the Ho3+ : (5F4, 5S2)→ 5I8 transitions was observed in Nd3+-Ho3+ co-doped ZrF4-based fluoride glasses under 800 nm excitation. As an attempt to enhance Ho3+ up-conversion luminescences in the Nd3+ – Ho3+ co-doped ZrF4-based glasses, Yb3+ ions were added to the glasses. As a result it was found that, in 800 nm excitation of 60 ZrF4. 30BaF2. (8-x)LaF3. lNdF3. xYbF3. 1HoF3 glasses (x=0 to 7), sensitized up-conversion luminescences are observed at around 490 nm (blue), 545 nm (green), and 650 nm (red), which
correspond to the Ho3+ : 5F3 → 5I8, ( 5F4, 5S2)→5I8 and 5F5→ 5I8 transitions respectively. The intensities of the green and red emissions in a 3 mol % YbF3-containing glass were about 50 times stronger than those glasses without YbF3. This is based on sensitization due to Yb3+ ions. In particular, the green emission was extremely strong and the Nd3+-Yb3+-Ho3+ co-doped ZrF4-based glasses have a high possibility of realizing a green up-conversion laser glass. In this paper the up-conversion mechanism
in the glasses is discussed in detail. 相似文献
22.
O P Costa Leonardo Christine Chung-Wei Lin Debora Grossi Bevilaqua Marisa Cota Mancini Anne K Swisher Chad Cook Dan Vaughn Mark R Elkins Umer Sheikh Ann Moore Gwendolen Jull Rebecca L Craik Christopher G Maher Rinaldo Roberto de Jesus Guirro Amélia Pasqual Marques Michele Harms Dina Brooks Guy G Simoneau John Henry Strupstad 《Cardiopulmonary Physical Therapy Journal》2013,24(1):4-6
23.
1 Introduction Thechemicaleffectsofultrasoundareduetohighpressureproducedduringviolentcollapseofcavitationbubbles.Thereactionsdonottake placehomoge neouslyinthesolutionbutin”hotspots”wherecavi tationbubblespulsateorcollapse .Duringtheadiabat iccompressio… 相似文献