Cordierite ceramic powders were prepared by solid reaction at low temperatures using gangue as main starting material and adjusting component oxides in formulations. The powders were characterized by XRD, SEM and EDS....Cordierite ceramic powders were prepared by solid reaction at low temperatures using gangue as main starting material and adjusting component oxides in formulations. The powders were characterized by XRD, SEM and EDS. The emphasis was placed on the reaction mechanism and phase transformation of synthesized powders. The results show that cordierite ceramic powders can be synthesized at 1 150 - 1 250 % for 3 - 5 h and its morphology is irregularly granular. The synthesis temperature has an important effect on the phase transformations of powders but the reaction time only has a little effect. The impurities in gangue result in the detected secondary magnesium aluminate spinel and the decreased synthesis temperature.展开更多
A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of...A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of osteoblasts to mechanical signal of physiological stretching are evaluated from three aspects: collagen production, extracellular inorganic calcium secretion and ALP activity. The results show that osteoblasts decrease the collagen synthesis, calcium secretion and ALP activity compared to the control cells (65.82%,73.51%,48.10% respectively), confirming that cyclic stretching at 1500 με inhabits the physiological activity of osteoblasts.展开更多
文摘Cordierite ceramic powders were prepared by solid reaction at low temperatures using gangue as main starting material and adjusting component oxides in formulations. The powders were characterized by XRD, SEM and EDS. The emphasis was placed on the reaction mechanism and phase transformation of synthesized powders. The results show that cordierite ceramic powders can be synthesized at 1 150 - 1 250 % for 3 - 5 h and its morphology is irregularly granular. The synthesis temperature has an important effect on the phase transformations of powders but the reaction time only has a little effect. The impurities in gangue result in the detected secondary magnesium aluminate spinel and the decreased synthesis temperature.
文摘A four-point bending apparatus is used to investigate the effects of stretching on collagen synthesis, mineralization and differentiation of osteoblasts. Cells are stretched at 1500 με for 24 hours. The responses of osteoblasts to mechanical signal of physiological stretching are evaluated from three aspects: collagen production, extracellular inorganic calcium secretion and ALP activity. The results show that osteoblasts decrease the collagen synthesis, calcium secretion and ALP activity compared to the control cells (65.82%,73.51%,48.10% respectively), confirming that cyclic stretching at 1500 με inhabits the physiological activity of osteoblasts.
