Vickers indentation was introduced into the originally in-plane and out-of-plane poled PLZT ceramics.The Raman spectra were in-situ recorded at selected crack tips before and after the indentations,as well as after th...Vickers indentation was introduced into the originally in-plane and out-of-plane poled PLZT ceramics.The Raman spectra were in-situ recorded at selected crack tips before and after the indentations,as well as after the applications of external electric field.The results show that the changes in Raman intensities of optical modes could be sensitively related to 90° domain switching around the crack tips which are strongly dependent on the directions of original polarization and geometric locations.When the direction of electric field was perpendicular to the direction of original polarization,the 90° domain switching at crack tips of the Vickers indentation on the originally in-plane poled PLZT ceramics caused most significant change in the Raman intensity,which inhibited the crack growth.However,when the direction of electric field was parallel to the direction of original polarization,the growth of crack tips became predominantly without the 90° domain switching,which led to the crack growth.展开更多
以甲基三乙氧基硅烷(MTES)和二甲基二乙氧基硅烷(DMDES)为前驱体,水为反应物,乙醇为溶剂,盐酸和氨水为催化剂,十六烷基三甲基溴化铵(CTAB)为表面活性剂,通过溶胶-凝胶法和超临界干燥制备得到疏水亲油MTES-DMDES型柔性气凝胶块体。通过...以甲基三乙氧基硅烷(MTES)和二甲基二乙氧基硅烷(DMDES)为前驱体,水为反应物,乙醇为溶剂,盐酸和氨水为催化剂,十六烷基三甲基溴化铵(CTAB)为表面活性剂,通过溶胶-凝胶法和超临界干燥制备得到疏水亲油MTES-DMDES型柔性气凝胶块体。通过红外光谱、X射线衍射、扫描电镜、X射线能量色谱、应力-应变,疏水性测试、热重等测试分析发现,气凝胶具有三维网络骨架结构,密度低至0.0897 g/cm^3,最大应变达到80%,应力低至36.85 k Pa,疏水接触角为153.6°,热稳定温度高达400℃。能从水中快速高效去除油污,是具有广阔应用前景的油/水分离材料。展开更多
基金Project(2006L2003)supported by the Fujian Key Laboratory of Advanced Materials,ChinaProject(10802070)supported by the National Natural Science Foundation of China
文摘Vickers indentation was introduced into the originally in-plane and out-of-plane poled PLZT ceramics.The Raman spectra were in-situ recorded at selected crack tips before and after the indentations,as well as after the applications of external electric field.The results show that the changes in Raman intensities of optical modes could be sensitively related to 90° domain switching around the crack tips which are strongly dependent on the directions of original polarization and geometric locations.When the direction of electric field was perpendicular to the direction of original polarization,the 90° domain switching at crack tips of the Vickers indentation on the originally in-plane poled PLZT ceramics caused most significant change in the Raman intensity,which inhibited the crack growth.However,when the direction of electric field was parallel to the direction of original polarization,the growth of crack tips became predominantly without the 90° domain switching,which led to the crack growth.
文摘以甲基三乙氧基硅烷(MTES)和二甲基二乙氧基硅烷(DMDES)为前驱体,水为反应物,乙醇为溶剂,盐酸和氨水为催化剂,十六烷基三甲基溴化铵(CTAB)为表面活性剂,通过溶胶-凝胶法和超临界干燥制备得到疏水亲油MTES-DMDES型柔性气凝胶块体。通过红外光谱、X射线衍射、扫描电镜、X射线能量色谱、应力-应变,疏水性测试、热重等测试分析发现,气凝胶具有三维网络骨架结构,密度低至0.0897 g/cm^3,最大应变达到80%,应力低至36.85 k Pa,疏水接触角为153.6°,热稳定温度高达400℃。能从水中快速高效去除油污,是具有广阔应用前景的油/水分离材料。
