This work aims at developing a new and reliable biomaterial for implant application by fabricating calcium phosphate/Al2O3 biocomposite coating on medical titanium using a hybrid technique of anodic oxidation and hydr...This work aims at developing a new and reliable biomaterial for implant application by fabricating calcium phosphate/Al2O3 biocomposite coating on medical titanium using a hybrid technique of anodic oxidation and hydrothermal treatment. The pre- and post-anodized samples were investigated by scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. The results indicated that porous anodic alumina film containing Ca and P was obtained on the as-prepared Al-Ti substrate through anodization, and the subsequent hydrothermal treatment led to the formation of calcium phosphate crystals. SEM and TEM results showed that calcium phosphate crystals were in nanometer, in-situ embedded in the walls of the cylindrical structure of anodic alumina, and finally formed a thin and porous top layer on the anodic alumina layer. The nanometer effect of calcium phosphate top layer, the porous and cylindrical microstructure of calcium phosphate/Al2O3-Ti, and the in-situ growth effect are expect to possess a very good combination of bioactivity and mechanical integrity.展开更多
Pyridine, CO and SO 2 were used as probes to characterize the mixed oxides Al 2O 3/SiO 2 by TPD technique. XRD study showed mullite was the major composition of the mixed oxides. The tail gases were analyzed by gas ch...Pyridine, CO and SO 2 were used as probes to characterize the mixed oxides Al 2O 3/SiO 2 by TPD technique. XRD study showed mullite was the major composition of the mixed oxides. The tail gases were analyzed by gas chromatography. The results showed that the nanocrystal mixed oxides exhibited a good adsorbability for pyridine, CO and SO 2. During desorption of pyridine and CO, CO 2 was detected in desorbed mixtures and in the case of SO 2 solid sulphur was found.展开更多
文摘随着高速旋转机械材料的发展,对环氧树脂复合材料基体的性能提出了更高的要求.文章对相关的一种基体材料即环氧树脂/纳米氧化铝聚合物的制备工艺和性能进行研究.采用对纳米颗粒表面进行硅烷偶联处理和机械分散与超声波振动分散相结合的方法,实现了氧化铝纳米粒子在环氧树脂中的分散.经透射电镜(TEM)观察,改性后的纳米粒子能够较均匀地分散在环氧树脂中.并研究了溶液pH值、超声波分散时间对纳米粒子改性的影响,得出了最佳的工艺条件:溶液pH值为4～5,超声波分散时间为20 min.
文摘This work aims at developing a new and reliable biomaterial for implant application by fabricating calcium phosphate/Al2O3 biocomposite coating on medical titanium using a hybrid technique of anodic oxidation and hydrothermal treatment. The pre- and post-anodized samples were investigated by scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. The results indicated that porous anodic alumina film containing Ca and P was obtained on the as-prepared Al-Ti substrate through anodization, and the subsequent hydrothermal treatment led to the formation of calcium phosphate crystals. SEM and TEM results showed that calcium phosphate crystals were in nanometer, in-situ embedded in the walls of the cylindrical structure of anodic alumina, and finally formed a thin and porous top layer on the anodic alumina layer. The nanometer effect of calcium phosphate top layer, the porous and cylindrical microstructure of calcium phosphate/Al2O3-Ti, and the in-situ growth effect are expect to possess a very good combination of bioactivity and mechanical integrity.
文摘Pyridine, CO and SO 2 were used as probes to characterize the mixed oxides Al 2O 3/SiO 2 by TPD technique. XRD study showed mullite was the major composition of the mixed oxides. The tail gases were analyzed by gas chromatography. The results showed that the nanocrystal mixed oxides exhibited a good adsorbability for pyridine, CO and SO 2. During desorption of pyridine and CO, CO 2 was detected in desorbed mixtures and in the case of SO 2 solid sulphur was found.
