A theoretical model of the refractive index changes of the TE and TM modes in an electro-absorption modulator （EAM） is deduced. The photon absorption and refractive index changes are analyzed numerically. The influe...A theoretical model of the refractive index changes of the TE and TM modes in an electro-absorption modulator （EAM） is deduced. The photon absorption and refractive index changes are analyzed numerically. The influence of pump intensity on the phase difference between the TE and TM modes is studied. The polarization rotation effect is obtained in the EAM, and a novel all-optical fiber loop buffer is designed.展开更多
The transport of Cu(II)from aqueous solutions containing buffer media through hollow fiber supported liquid membrane(HFSLM)using di(2-ethylhexyl)phosphoric acid(D2EHPA)dissolved in kerosene as membrane phase and hydro...The transport of Cu(II)from aqueous solutions containing buffer media through hollow fiber supported liquid membrane(HFSLM)using di(2-ethylhexyl)phosphoric acid(D2EHPA)dissolved in kerosene as membrane phase and hydrochloric acid as striping phase was investigated.A set of factors were studied,including tube side velocity,shell side velocity,pH of the feed phase,Cu(II)concentration in the feed phase,buffer media concentration and D2EHPA concentration in the membrane phase.Experimental results indicate that the mass transfer coefficient increases with increasing both carrier concentration in the organic phase and flow rates on the tube side and shell side,and decreases with increasing initial Cu(II)concentration in the feed phase.With increasing pH value and acetate concentration in the feed phase,the mass transfer coefficient reaches a maximum value then decreases.The optimal operating conditions are obtained at pH value of 4.44 and 0.1 mol·L -1 acetic ion concentration in feed phase,and carrier volume fraction of around 10%in kerosene as organic phase.A mathematical model of the transport mechanism through HFSLM is developed.The modeled results agree well with the experimental ones.展开更多
【目的】植物纤维多孔材料的制备通常采用热分解型化学发泡剂,研究碳酸氢铵(NH4HCO_(3))、碳酸氢钠(NaHCO_(3))、偶氮二甲酰胺/碳酸氢钠(AC/NaHCO_(3))以及AC/NaHCO_(3)不同复配比例对植物纤维多孔材料的泡孔结构及缓冲性能的影响。【...【目的】植物纤维多孔材料的制备通常采用热分解型化学发泡剂,研究碳酸氢铵(NH4HCO_(3))、碳酸氢钠(NaHCO_(3))、偶氮二甲酰胺/碳酸氢钠(AC/NaHCO_(3))以及AC/NaHCO_(3)不同复配比例对植物纤维多孔材料的泡孔结构及缓冲性能的影响。【方法】以漂白针叶木浆为主要原料,添加NH4HCO_(3)、NaHCO_(3)、AC/NaHCO_(3)3种不同的发泡剂,以及AC/NaHCO_(3)不同复配比例条件下,采用微波成型工艺制备植物纤维多孔材料。利用Image Pro Plus 6.0软件对植物纤维多孔材料泡孔的显微图像进行处理分析,得到孔隙率、孔径大小及泡孔分布等参数;通过静态压缩测试分析材料力学性能和单位体积变形能。【结果】对比3种发泡剂试样,AC/NaHCO_(3)复配发泡剂制备的植物纤维多孔材料具有较高的孔隙率且泡孔分布较均匀,得到最小缓冲系数为4.93,具有良好的缓冲特性;对比AC/NaHCO_(3)3种不同配比的试样,得出比例为2∶1及3∶1时发泡效果较好,泡孔分布较均匀,其中AC/NaHCO_(3)比例为2∶1时材料得到的最小缓冲系数最小,缓冲性能良好。【结论】AC/NaHCO_(3)复配发泡剂能在更大温度范围内持续产生气体,且AC/NaHCO_(3)比例为2∶1时,发泡剂发气均匀,制备的植物纤维多孔材料泡孔分布均匀性更好,材料缓冲性能优良,此结果可为研究发泡剂对植物纤维多孔材料的泡孔结构及缓冲性能的影响提供参考。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61077014)the National Basic Research Program of China(Grant No.2010CB327601)
文摘A theoretical model of the refractive index changes of the TE and TM modes in an electro-absorption modulator （EAM） is deduced. The photon absorption and refractive index changes are analyzed numerically. The influence of pump intensity on the phase difference between the TE and TM modes is studied. The polarization rotation effect is obtained in the EAM, and a novel all-optical fiber loop buffer is designed.
基金Supported by the Program for New Century Excellent Talents in University （NCET-05-0122） the National Natural Science Foundation of China（20576008 20706003） the Ph.D.Programs Foundation of Ministry of Education of China（200800100001） The authors are grateful to Prof. Xiaolong Lii of Tianjin Polytechnic University for supplying PVDF hollow fibers.
文摘The transport of Cu(II)from aqueous solutions containing buffer media through hollow fiber supported liquid membrane(HFSLM)using di(2-ethylhexyl)phosphoric acid(D2EHPA)dissolved in kerosene as membrane phase and hydrochloric acid as striping phase was investigated.A set of factors were studied,including tube side velocity,shell side velocity,pH of the feed phase,Cu(II)concentration in the feed phase,buffer media concentration and D2EHPA concentration in the membrane phase.Experimental results indicate that the mass transfer coefficient increases with increasing both carrier concentration in the organic phase and flow rates on the tube side and shell side,and decreases with increasing initial Cu(II)concentration in the feed phase.With increasing pH value and acetate concentration in the feed phase,the mass transfer coefficient reaches a maximum value then decreases.The optimal operating conditions are obtained at pH value of 4.44 and 0.1 mol·L -1 acetic ion concentration in feed phase,and carrier volume fraction of around 10%in kerosene as organic phase.A mathematical model of the transport mechanism through HFSLM is developed.The modeled results agree well with the experimental ones.
文摘【目的】植物纤维多孔材料的制备通常采用热分解型化学发泡剂,研究碳酸氢铵(NH4HCO_(3))、碳酸氢钠(NaHCO_(3))、偶氮二甲酰胺/碳酸氢钠(AC/NaHCO_(3))以及AC/NaHCO_(3)不同复配比例对植物纤维多孔材料的泡孔结构及缓冲性能的影响。【方法】以漂白针叶木浆为主要原料,添加NH4HCO_(3)、NaHCO_(3)、AC/NaHCO_(3)3种不同的发泡剂,以及AC/NaHCO_(3)不同复配比例条件下,采用微波成型工艺制备植物纤维多孔材料。利用Image Pro Plus 6.0软件对植物纤维多孔材料泡孔的显微图像进行处理分析,得到孔隙率、孔径大小及泡孔分布等参数;通过静态压缩测试分析材料力学性能和单位体积变形能。【结果】对比3种发泡剂试样,AC/NaHCO_(3)复配发泡剂制备的植物纤维多孔材料具有较高的孔隙率且泡孔分布较均匀,得到最小缓冲系数为4.93,具有良好的缓冲特性;对比AC/NaHCO_(3)3种不同配比的试样,得出比例为2∶1及3∶1时发泡效果较好,泡孔分布较均匀,其中AC/NaHCO_(3)比例为2∶1时材料得到的最小缓冲系数最小,缓冲性能良好。【结论】AC/NaHCO_(3)复配发泡剂能在更大温度范围内持续产生气体,且AC/NaHCO_(3)比例为2∶1时,发泡剂发气均匀,制备的植物纤维多孔材料泡孔分布均匀性更好,材料缓冲性能优良,此结果可为研究发泡剂对植物纤维多孔材料的泡孔结构及缓冲性能的影响提供参考。
