Cerium doped lutetium

The emitted gamma photons produced by positron-electron annihilation can be detected using scintillation crystal detectors such as sodiiun iodide (Nal), bismuth germaniiun oxide (BGO) and cerium doped lutetium oxyorthosili-cate (LSO). The short half-life of most positron emitters leads to high specific activity. Only a very small quantity of radio-labeled molecules is thus required, making positron annihilation detection techniques very non-invasive. In fact, practical catalyst studies can be carried out using less than 37 kBq... 

Lutetium is also a very rare metal, with a world production (as lutetium oxide) of approximately 10 tons per year. One commercial application is known it is used as a P-emitter, (when Lu-176 has been exposed to neutron activation) in the oil refining industry (Emsley 2001). It was used in so-called-bubble memory, a technology for computer memory that has become obsolete, since hard disks have made their rapid substantial advance. It is still used in scintillation crystals for PET-scanners (positron emission scanners). It is used here in the form of cerium-doped Lutetium oxy-orthosilicate (LSO), with the formula Ce2x Lu2(l — x) SiOs, where x is within tire range from approximately 2 x 10 to approximately 3 X 10 (Melcher 1990 Daghighian et al. 1993). 

Li HL, Liu XI, Huang LP (2005) Fabrication of transparent cerium-doped lutetium aluminum garnet (LuAG Ce) ceramics by a solid-state reaction method. J Am Ceram Soc 88 3226-3228... 

Li JL, Xu J, Shi Y, Qi HF, Xie JJ, Lei F (2014) Fabrication and microstructure of cerium doped lutetium aluminum garnet (Ce LuAG) transparent ceramics by solid-state reaction method. Mater Res Bull 55 161-167... 

Li HL, Liu XJ, Xie RJ, Zhou GH, Hirosaki N, Pu XP et al (2008) Cerium-doped lutetium aluminum garnet phosphors and optically transparent ceramics prepared from powder precursors by a urea homogeneous precipitation method. Jpn J Appl Phys 47 1657-1661... 

Bartram RH, Hamilton DS, Kappers LA, Lempicki A, Glodo J, Schweitzer JS et al (1999) Electron traps and transfer efficiency in cerium-doped lutetium oxyorthosilicate sdntillatms. 

Melcher CL, Schweitzer IS. Cerium-doped lutetium oxyorthosilicate a fast, efficient new scintillator. IEEE Trans Nucl Sci 1992 39 502-505. 

H.L. Li, X.J. Liu, and L.P. Huang, Fabrication of Transparent Cerium-Doped Lutetium Aluminum Garnet (LuAGiCe) Ceramics by a Solid-State Reaction Method, //4m.Cera/n.5<>c., 88[ll 3226-3228(2005). 

Cherepy, N. J., Kuntz, J. D., Tillotson, T. M., Speaks, D. T., Payne, S. A., Chai, B. H. T., Porter-Chapman, Y, Derenzo, S. E. 2007. Cerium-doped single crystal and transparent ceramic lutetium aluminum garnet scintillators. Nuclear Instruments and Methods in Physics Research A 579 38-41. 

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