微乳液法制备纳米草酸钆的热解机理的研究

Gd₂O₃∶Tb³⁺ luminescent nanoparticles were prepared by the thermal decomposition of the nanosized oxlate prepared in the reverse microemulsions based on triton X-100 / n-hexyl alcohol, n-octane, and water. From TG-DTA, XRD and FTIR analyses, the mechanism of thermal decomposition of the nanosized oxalate precursor is suggested as follows: Gd₂(C₂O₄)₃·10H₂O → Gd₂(C₂O₄)₃ + 10H₂O, Gd₂(C₂O₄)₃ → Gd₂O₂(CO₃) + 3CO +2CO₂, Gd₂O₂(CO₃) → Gd₂O₃ + CO₂. The kinetic parameters of thermal decomposition reaction-activation energy E of stage 2 and 3 are 194.6 kJ·mol^-1, 110.9 kJ·mol^-1, respectively, using Ozawa method. And the reaction order n is 2.9 and 0.43, respectively, according to the TG curves.     

双连续微乳模板合成羟基磷灰石仿生物骨材料的研究

为制备具有与天然生物骨磷灰石结构相似的羟基磷灰石（hydroxyapatites简称HAP或HA）材料，依据生物矿化的原理，通过以十六烷基三甲基溴化铵（CTAB）作为表面活性剂，正己醇为助表面活性剂，十六烷为油相和水作出的拟三元相图，找到体系所形成的双连续微乳液作为模板，控制矿化材料的成核和生长，并用SEM，TEM，XRD，IR等手段对合成的样品进行了形貌和结构的表征，并将其与共沉淀法制备的HAP在模拟体液中的溶解性进行了比较。结果表明：得到的矿化产物是具有棒状的六方晶体组成羟基磷灰石矿化材料，其结构参数a₀=0.920，c₀=0.688，与天然生物骨材料较相似，抗体液溶解性比共沉淀法制备的优越。