By using a simply liquid phase method at a low temperature, rutile TiO 2 nanowhiskers were successfully prepared from TiCl 4 aqueous solution at 70 ℃ after aging for 11 d. The obtained TiO 2 nanowhiskers were charact...By using a simply liquid phase method at a low temperature, rutile TiO 2 nanowhiskers were successfully prepared from TiCl 4 aqueous solution at 70 ℃ after aging for 11 d. The obtained TiO 2 nanowhiskers were characterized by means of TEM,HRTEM and XRD. The results show that the nanowhiskers are rutile crystals growing along c-axis direction with a length of 100150 nm and a diameter 68 nm. The simple fabrication method of TiO 2 nanowhiskers will promote practical application of 1D TiO 2.展开更多
采用高效制备液相色谱法从荷叶(N elum bo nucifera G aertn)中分离制备荷叶黄酮类化合物。用60%乙醇回流提取荷叶,粗提液浓缩后经D-101柱及聚酰胺柱色谱分离,再在Symm etry P repTMC18柱上分离,以水-乙腈为流动相进行梯度洗脱(流速为5....采用高效制备液相色谱法从荷叶(N elum bo nucifera G aertn)中分离制备荷叶黄酮类化合物。用60%乙醇回流提取荷叶,粗提液浓缩后经D-101柱及聚酰胺柱色谱分离,再在Symm etry P repTMC18柱上分离,以水-乙腈为流动相进行梯度洗脱(流速为5.0m L/m in),得到了3种黄酮类化合物。经紫外光谱、红外光谱、核磁共振及质谱分析,确定该3种物质分别为金丝桃苷、异槲皮苷和紫云英苷。所制备的3种化合物的纯度都在97%以上,其中紫云英苷为首次从荷叶中分离得到。展开更多
文摘By using a simply liquid phase method at a low temperature, rutile TiO 2 nanowhiskers were successfully prepared from TiCl 4 aqueous solution at 70 ℃ after aging for 11 d. The obtained TiO 2 nanowhiskers were characterized by means of TEM,HRTEM and XRD. The results show that the nanowhiskers are rutile crystals growing along c-axis direction with a length of 100150 nm and a diameter 68 nm. The simple fabrication method of TiO 2 nanowhiskers will promote practical application of 1D TiO 2.
文摘采用高效制备液相色谱法从荷叶(N elum bo nucifera G aertn)中分离制备荷叶黄酮类化合物。用60%乙醇回流提取荷叶,粗提液浓缩后经D-101柱及聚酰胺柱色谱分离,再在Symm etry P repTMC18柱上分离,以水-乙腈为流动相进行梯度洗脱(流速为5.0m L/m in),得到了3种黄酮类化合物。经紫外光谱、红外光谱、核磁共振及质谱分析,确定该3种物质分别为金丝桃苷、异槲皮苷和紫云英苷。所制备的3种化合物的纯度都在97%以上,其中紫云英苷为首次从荷叶中分离得到。
