Title: Single crystal decolourization by adding doping material e.g. zinc tungstate
Application Number: 88100191 Application Date: 1988.01.28
Publication Number: 1032200 Publication Date: 1989.04.05
Approval Pub. Date: Granted Pub. Date: 1990.01.03
International Classifi-cation: C30B15/04,C30B29/32
Applicant(s) Name: Beijing Polytechnical Univ. Address:
Inventor(s) Name: Liu Guoqing, Wang Liangmiao, Wang Qizong
Attorney & Agent: LOU GENJI ZHANG HUI
Abstract:
     This impurifying-decolouring technology for zinc tungstate crystal belongs to the field of making tungstate series of crystals. For general such technologies, Sb2O3, or Bi2O3, or Ag is used as the impurifying decolourant and their common shortcoming is that the clear crystal with big size can not be pulled out. This invention features that Nb2O3 is used as its impurifying material and a clear Zn WO4 crystal with a big size can be obtained under following conditions: impurifying ratio:(2 muliplied by 10 to the power of minus 5-10 to the power of minus 4) pulling speed: 3-6 mm/h, revolving speed: 20-30 turns/m and temp. lowering speed (after finishing growth): 40-60 deg C/h. Its luminous nature is identical to that of pure ZnWO4 crystal and its energy resolving power can reach 13-14%.
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