This work focuses on the preparation and characterization of flat sheet membrane based on modified polyether ether keetone (PEEK-WC). Additives, such as dibutyl phatalate (DBP) and diethyl hexyl phosphoric acid (DEHPA...This work focuses on the preparation and characterization of flat sheet membrane based on modified polyether ether keetone (PEEK-WC). Additives, such as dibutyl phatalate (DBP) and diethyl hexyl phosphoric acid (DEHPA), were used to investigate their effect on membranes properties which are prepared by immersion precipitation. For that, several techniques were used to characterize membranes like thermal analyses, scanning electron microscopy and microanalyses. SEM pictures show versatile structures of the membranes from dense to porous membranes characterized by a sponge and finger like structure. Moreover, microanalyses of both surfaces, bottom and top surfaces show an aggregation of DEHPA at the top surface of the membrane. However, by adding dibutylphtalate, a well dispersion of the extractant was observed. Initially, micro-porous membranes were used in supported liquid membranes experiments for Ni(II) metal ions transports using diethyl hexyl phosphoric acid (DEHPA) as carrier. The extraction efficiency was very low about 28%, but enhanced by adding xylene to the organic phase. However, the modified membranes (with additives) by DBP and DEHPA were used on solid liquid extraction of Ni(II). The results show that by adding the plasticizer and the extractant, the efficiency of the system reached 63%.展开更多
目的探讨不同扫描参数对FLAIR序列金属伪影的影响,以通过调整扫描参数来减小金属伪影。方法选用镍铬合金制成左下6标准桩核冠模型。应用1.5 T MRI扫描仪对桩核冠模型行横断面FLAIR扫描,扫描参数为西门子1.5T MR扫描仪的推荐值。保持其...目的探讨不同扫描参数对FLAIR序列金属伪影的影响,以通过调整扫描参数来减小金属伪影。方法选用镍铬合金制成左下6标准桩核冠模型。应用1.5 T MRI扫描仪对桩核冠模型行横断面FLAIR扫描,扫描参数为西门子1.5T MR扫描仪的推荐值。保持其它参数与标准扫描序列参数一致,逐一改变以下各参数进行成像:TR、TE、FOV、Matrix、BW、NEX、ETL、Thk、FA。确定伪影最大的层面并测量伪影面积。应用SAS V8统计学软件进行统计学分析。结果调整不同FOV值,不同Matrix值及FA值,镍铬合金伪影大小差异有统计学意义(F值分别为F=67.04,F=48.75,F=5.61,P<0.05)。结论在FLAIR序列中,可以通过减小视野、增加矩阵,增大翻转角减小金属伪影。展开更多
文摘This work focuses on the preparation and characterization of flat sheet membrane based on modified polyether ether keetone (PEEK-WC). Additives, such as dibutyl phatalate (DBP) and diethyl hexyl phosphoric acid (DEHPA), were used to investigate their effect on membranes properties which are prepared by immersion precipitation. For that, several techniques were used to characterize membranes like thermal analyses, scanning electron microscopy and microanalyses. SEM pictures show versatile structures of the membranes from dense to porous membranes characterized by a sponge and finger like structure. Moreover, microanalyses of both surfaces, bottom and top surfaces show an aggregation of DEHPA at the top surface of the membrane. However, by adding dibutylphtalate, a well dispersion of the extractant was observed. Initially, micro-porous membranes were used in supported liquid membranes experiments for Ni(II) metal ions transports using diethyl hexyl phosphoric acid (DEHPA) as carrier. The extraction efficiency was very low about 28%, but enhanced by adding xylene to the organic phase. However, the modified membranes (with additives) by DBP and DEHPA were used on solid liquid extraction of Ni(II). The results show that by adding the plasticizer and the extractant, the efficiency of the system reached 63%.
文摘目的探讨不同扫描参数对FLAIR序列金属伪影的影响,以通过调整扫描参数来减小金属伪影。方法选用镍铬合金制成左下6标准桩核冠模型。应用1.5 T MRI扫描仪对桩核冠模型行横断面FLAIR扫描,扫描参数为西门子1.5T MR扫描仪的推荐值。保持其它参数与标准扫描序列参数一致,逐一改变以下各参数进行成像:TR、TE、FOV、Matrix、BW、NEX、ETL、Thk、FA。确定伪影最大的层面并测量伪影面积。应用SAS V8统计学软件进行统计学分析。结果调整不同FOV值,不同Matrix值及FA值,镍铬合金伪影大小差异有统计学意义(F值分别为F=67.04,F=48.75,F=5.61,P<0.05)。结论在FLAIR序列中,可以通过减小视野、增加矩阵,增大翻转角减小金属伪影。
