为了降低Ca Ti O3-（La,Nd）Al O3（简称CT-LNA）陶瓷的烧结温度和提高其介电性能,研究纳米Al2O3对Ca Ti O3-（La,Nd）Al O3陶瓷的烧结温度和介电性能的影响。固相法制备粉料,采用XRD和SEM分析其晶相和显微结构,用网络分析测试样品的介...为了降低Ca Ti O3-（La,Nd）Al O3（简称CT-LNA）陶瓷的烧结温度和提高其介电性能,研究纳米Al2O3对Ca Ti O3-（La,Nd）Al O3陶瓷的烧结温度和介电性能的影响。固相法制备粉料,采用XRD和SEM分析其晶相和显微结构,用网络分析测试样品的介电参数,结果表明,纳米Al2O3可促进陶瓷烧结,在1320~1400℃范围内可烧结成瓷,并具有较好的微波介电性能。当纳米Al2O3含量为50 wt%时,陶瓷在1340℃烧结可获得优良的微波介电性能：介电常数为42.6,Q×f值高达34,000GHz,频率温度系数为＋4.8 ppm/℃。展开更多
针对以海藻酸钠为代表的传统固定化材料制备的微藻胶球传质性能较差,对水中总磷去除率低的问题,开发了纳米Al2O3-海藻酸钠联合固定化小球藻胶球,研究了初始总磷浓度、胶球粒径和粒数对联合固定化小球藻去除总磷的影响。结果表明:纳米Al...针对以海藻酸钠为代表的传统固定化材料制备的微藻胶球传质性能较差,对水中总磷去除率低的问题,开发了纳米Al2O3-海藻酸钠联合固定化小球藻胶球,研究了初始总磷浓度、胶球粒径和粒数对联合固定化小球藻去除总磷的影响。结果表明:纳米Al2O3增加了固定化小球藻胶球的比表面积,促进了小球藻对水中总磷的去除,总磷去除率随着胶球加入量的增加和胶球粒径的减小而提高。纳米Al2O3-海藻酸钠联合固定化小球藻胶球的最优制备方案如下:将0.15 g纳米Al2O3加入到30 m L浓度为1.8%海藻酸钠溶液中,然后再加入小球藻至藻细胞密度为2×106cell/m L,交联CaCl2浓度为1%。胶球重复使用3次时总磷去除率仍达到77.51%。展开更多
A new nanometer material, nano-Al2O3 with carbon fibre as the carrier, was employed for the removal of Cd with low concentrations from polluted water. The characterization of the material was carried out by means of S...A new nanometer material, nano-Al2O3 with carbon fibre as the carrier, was employed for the removal of Cd with low concentrations from polluted water. The characterization of the material was carried out by means of SEM and TEM. Batch adsorption and elution experiments were carried out to determine the adsorption properties of Cd on the new adsorbent. The classical Thomas model was applied to estimating the equilibrium coefficients of Cd adsorption and the saturated adsorption ability. The results show that the Thomas model is fit for describing the kinetic adsorption process, and the maximum adsorption capacity of the nanometer Al2O3/carbon is 69.29 mg/g. The resulting information also indicates that the desorption of Cd eluted with de-ionized water at a rate of 9.8 mL/min can be neglected. With the advantage of a high adsorption capacity for removing low concentration Cd, the Al2O3/carbon fibre possesses the potentiality to be an effective adsorbent for the removal of Cd from polluted water.展开更多
文摘为了降低Ca Ti O3-（La,Nd）Al O3（简称CT-LNA）陶瓷的烧结温度和提高其介电性能,研究纳米Al2O3对Ca Ti O3-（La,Nd）Al O3陶瓷的烧结温度和介电性能的影响。固相法制备粉料,采用XRD和SEM分析其晶相和显微结构,用网络分析测试样品的介电参数,结果表明,纳米Al2O3可促进陶瓷烧结,在1320~1400℃范围内可烧结成瓷,并具有较好的微波介电性能。当纳米Al2O3含量为50 wt%时,陶瓷在1340℃烧结可获得优良的微波介电性能：介电常数为42.6,Q×f值高达34,000GHz,频率温度系数为＋4.8 ppm/℃。
文摘针对以海藻酸钠为代表的传统固定化材料制备的微藻胶球传质性能较差,对水中总磷去除率低的问题,开发了纳米Al2O3-海藻酸钠联合固定化小球藻胶球,研究了初始总磷浓度、胶球粒径和粒数对联合固定化小球藻去除总磷的影响。结果表明:纳米Al2O3增加了固定化小球藻胶球的比表面积,促进了小球藻对水中总磷的去除,总磷去除率随着胶球加入量的增加和胶球粒径的减小而提高。纳米Al2O3-海藻酸钠联合固定化小球藻胶球的最优制备方案如下:将0.15 g纳米Al2O3加入到30 m L浓度为1.8%海藻酸钠溶液中,然后再加入小球藻至藻细胞密度为2×106cell/m L,交联CaCl2浓度为1%。胶球重复使用3次时总磷去除率仍达到77.51%。
基金Supported by the Starting Foundation for Graduated Doctors in Jilin University(No.420010302353).
文摘A new nanometer material, nano-Al2O3 with carbon fibre as the carrier, was employed for the removal of Cd with low concentrations from polluted water. The characterization of the material was carried out by means of SEM and TEM. Batch adsorption and elution experiments were carried out to determine the adsorption properties of Cd on the new adsorbent. The classical Thomas model was applied to estimating the equilibrium coefficients of Cd adsorption and the saturated adsorption ability. The results show that the Thomas model is fit for describing the kinetic adsorption process, and the maximum adsorption capacity of the nanometer Al2O3/carbon is 69.29 mg/g. The resulting information also indicates that the desorption of Cd eluted with de-ionized water at a rate of 9.8 mL/min can be neglected. With the advantage of a high adsorption capacity for removing low concentration Cd, the Al2O3/carbon fibre possesses the potentiality to be an effective adsorbent for the removal of Cd from polluted water.
