磷酸钙陶瓷植入体内后其表面类骨磷灰石层的形成是诱导成骨的先决条件.本实验在模拟体液(simulated body fluid, SBF)以人体骨骼肌组织内体液的正常生理流率(2mL/100mL.min)和偏离正常生理流率流动的动态条件下,研究在动态SBF中影响致...磷酸钙陶瓷植入体内后其表面类骨磷灰石层的形成是诱导成骨的先决条件.本实验在模拟体液(simulated body fluid, SBF)以人体骨骼肌组织内体液的正常生理流率(2mL/100mL.min)和偏离正常生理流率流动的动态条件下,研究在动态SBF中影响致密磷酸钙陶瓷表面类骨磷灰石层形成的因素.结果表明:在生理流率条件下,材料的粗糙表面有利于类骨磷灰石的形成,加大SBF中Ca2+、HPO2-4离子浓度,类骨磷灰石层的形成速度加快.比起通常使用的静态浸泡试验,SBF以生理流率流动的动态试验能够更好地模拟类骨磷灰石生长的体内环境.动态SBF对了解类骨磷灰石形成,进而了解磷酸钙陶瓷在体内诱导成骨机理是十分有用的.展开更多
Oxygen-permeable membranes derived from SrFe 0.2Co 0.8O 3-δ were investigated aiming at improving the permeability and integrity. An oxygen flux as large as 1.52×10 -6 mol/(cm 2·s) was observed for a 0.1 cm...Oxygen-permeable membranes derived from SrFe 0.2Co 0.8O 3-δ were investigated aiming at improving the permeability and integrity. An oxygen flux as large as 1.52×10 -6 mol/(cm 2·s) was observed for a 0.1 cm thick membrane of Ba 0.1Sr 0.9Sn 0.1Fe 0.1Co 0.8O 3-δ at 900 ℃ under a relatively small oxygen partial pressure gradient across the membrane(P′ O 2=2.13×10 4 Pa, P″ O 2=9.12×10 2 Pa ). The improved oxygen permeability may be attributed to the weaker association of oxygen vacancies as a consequence of partial substitution of Ba for Sr. The improved membrane stability of Sn-doped sample is likely due to the formation of SrSnO 3 second phase since the non-crystal Sr in grain boundaries is prior to reacting with Sn, which made the membrane more resistant to the corrosion from CO 2 and water vapor.展开更多
文摘磷酸钙陶瓷植入体内后其表面类骨磷灰石层的形成是诱导成骨的先决条件.本实验在模拟体液(simulated body fluid, SBF)以人体骨骼肌组织内体液的正常生理流率(2mL/100mL.min)和偏离正常生理流率流动的动态条件下,研究在动态SBF中影响致密磷酸钙陶瓷表面类骨磷灰石层形成的因素.结果表明:在生理流率条件下,材料的粗糙表面有利于类骨磷灰石的形成,加大SBF中Ca2+、HPO2-4离子浓度,类骨磷灰石层的形成速度加快.比起通常使用的静态浸泡试验,SBF以生理流率流动的动态试验能够更好地模拟类骨磷灰石生长的体内环境.动态SBF对了解类骨磷灰石形成,进而了解磷酸钙陶瓷在体内诱导成骨机理是十分有用的.
文摘Oxygen-permeable membranes derived from SrFe 0.2Co 0.8O 3-δ were investigated aiming at improving the permeability and integrity. An oxygen flux as large as 1.52×10 -6 mol/(cm 2·s) was observed for a 0.1 cm thick membrane of Ba 0.1Sr 0.9Sn 0.1Fe 0.1Co 0.8O 3-δ at 900 ℃ under a relatively small oxygen partial pressure gradient across the membrane(P′ O 2=2.13×10 4 Pa, P″ O 2=9.12×10 2 Pa ). The improved oxygen permeability may be attributed to the weaker association of oxygen vacancies as a consequence of partial substitution of Ba for Sr. The improved membrane stability of Sn-doped sample is likely due to the formation of SrSnO 3 second phase since the non-crystal Sr in grain boundaries is prior to reacting with Sn, which made the membrane more resistant to the corrosion from CO 2 and water vapor.
