【摘 要】
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Subsolidus phase equilibrium of Na2O-Sm2O3-B2O3 system has been investigated mainly by solid-state reaction and powder X-ray diffraclion method.There are nine definite three-phase regions and three te
【机 构】
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School of Materials Science and Engineering, Central South University, Changsha, Hunan 410083,People
【出 处】
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第十七届全国相图学术会议暨相图与材料设计国际研讨会
论文部分内容阅读
Subsolidus phase equilibrium of Na2O-Sm2O3-B2O3 system has been investigated mainly by solid-state reaction and powder X-ray diffraclion method.There are nine definite three-phase regions and three ternary compounds in this system under present experimental conditions.A novel compound Na3SmB2O6 was found and confirmed for the first time, along with its two homogeneous compounds Na3REB2O6 (RE=Pr,Eu) synthesized in this work The indexing results showed that the three compounds crystallize in the monoclinic space group P21/c (No.14) with the same structure type as both Na3NdB2O6 and Na3GdB2O6.The lattice parameters (a, b and c) of new borates Na3REB2O6 (RE=Pr, Sm, Eu) decrease linearly with the decrease of the radius of RE ion, which obeys the Lanthanide-contraction rule.The trigonal BO3 group in the Na3REB2O6 (RE=Pr, Sm) compounds was confirmed by their infrared absorption spectra.Thermal stabilities of the three new borates have been investigatec.
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