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Information × Registration Number 0214U006195, 0114U003040 , R & D reports Title Silicates and oxovanadates of lead, rare earth and alkali elements with the apatite structure. popup.stage_title Head Getman Evgeniy Ivanovich, Registration Date 17-02-2014 Organization Donetsk National University popup.description2 The silicates of rare earth elements Ln9(SiO4)6O(OH), as well as the solid solutions of composition La(9-x)Gdx(SiO4)6O(OH), La(9-x)Hox(SiO4)6O(OH) Na(1+x)Nd(9-x)(SiO4)6O(2-x) and Na(1+x)Gd(9-x)(SiO4)6O(2-x) have been first synthesized and investigated. The phase composition and unit cell parameters have been defined. The some features of crystal structure were refined by Rietveld method. The distribution of cations for crystal structure sites and interatomic distances have been defined. Content and distribution of the elements in the crystal structure of solid solutions have been investigated by SEM. The critical temperature of solid solution decomposition in the systems La(9-x)Lnx(SiO4)6O(OH) was calculated for all REE. The temperature ranges of stability of solid solutions were established. The correspondence of the experimental and calculated results was shown. The electrical properties of double silicates ceramics with sodium and rare earth elements have been studied. The ceramic with complex additive, which elements are evenly distributed on the grain boundaries and inside, has been developed. It is shown that the introduction into PZT of the multivalent additives Mg, Mn, Bi, Nb, combined with mechanical activation of the synthesized material leads to a reduction of the crystallite size down to 1-3 microns , to increase the dielectric permittivity of ceramics to 1800, the mechanical quality factor to 1000. Additional introduction of monovalent lithium (2-3 wt. %) achieved a reduction in the sintering temperature on the 100-200°. At the same time maintain high piezoelectric characteristics. Product Description popup.authors Ігнатов Олексій Володимирович Клімов Всеволод Валентинович Коротіна Дар'я Віталіївна Пасічник Людмила Валентинівна Понуровський Віталій Сергійович Селікова Неля Іванівна popup.nrat_date 2020-04-02 Close