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Borate wide range of complex and diverse structures, which function to find borate provides a wealth of resources. Some strontium, barium borate has some very superior properties, such as β-BaB 2 O 4 (β-BBO) is a superior performance of nonlinear optical materials , SrB 4 O 7 (SBO) has a very superior mechanical and optical properties. Therefore, in recent years at home and abroad for strontium, barium borate research and attention more and more, as our group of alkaline earth metal borate systems work continues, this thesis solution method, hydrothermal reaction temperature solid state reaction of a series of strontium, barium borate, and measured their thermal chemical properties. Using the solution method, by controlling the reaction temperature and the composition of raw materials synthesized SrB 2 O 4 · 4H 2 O, SrB 4 O 7 · 3.5H 2 O, SrB 6 O 10 · 5H 2 O, K 2 Sr [B 4 O 5 (OH) 4 ] 2 < / sub> · 10H 2 O, BaB 6 O 10 · 4.5H 2 O, BaB 2 O 4 · 4H 2 O, K 2 Ba [B 4 O 5 (OH) 4 ] 2 · 8H 2 O. With Sr (OH) 2 · 8H 2 O, H 3 BO 3 as raw material, the use of hydrothermal reaction synthesized SrB 2 O 4 · 2.5H 2 O, SrB 4 O 7 · 3H 2 O. By high temperature calcination SrB 2 O 4 · 4H 2 O, BaB 2 O 4 · 4H 2 O got SrB 2 O 4 , β-BaB 2 O 4 < / sub>. And the products were synthesized by chemical analysis, infrared spectroscopy, X-ray powder diffraction and thermal analysis (TG-DTA) and other phase identification, we got 11 kinds of high purity strontium, barium borate, which has four kinds of new borates: SrB 2 O 4 · 2.5H 2 O, SrB 4 O 7 · 3H 2 O, SrB 4 O 7 · 3.5H 2 O, BaB 6 O 10 · 4.5H 2 O, 7 known species of borates: SrB 2 O < sub> 4 , SrB 2 O 4 · 4H 2 O, SrB 6 O 10 · 5H 2 O, K 2 Sr [B 4 O 5 (OH) 4 ] 2 · 10H 2 O, β-BaB 2 O 4 , BaB 2 O 4 · 4H 2 O, K 2 Ba [B 4 O 5 (OH) 4 ] 2 · 8H 2 O. The use of micro-calorimeter at 298.15K were measured under these 11 kinds of synthesized strontium, barium borate were dissolved in pure phase 1mol · L -1 HCl aqueous molar enthalpy of solution, and then through Design thermodynamic cycle, obtained this 11 kinds of strontium, barium borate standard molar enthalpy of formation. In addition, the application of \>] 2 · 8H 2 O, K 2 Sr [B 4 O 5 (OH) 4 ] 2 · 10H 2 O thermodynamic properties were estimated. The results of this study further enriched borate chemical content of strontium, barium borate application provides a basis for synthesis and physico-chemical data. For functional strontium, barium borate material further development and utilization of positive significance.
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