A series of silica nanoscale materials（NIMs） were prepared through a facile acid-base neutralization. These silica derivatives consist of a nanosilica core, a charged corana（sulfonic acid SIT） attatched to the cor...A series of silica nanoscale materials（NIMs） were prepared through a facile acid-base neutralization. These silica derivatives consist of a nanosilica core, a charged corana（sulfonic acid SIT） attatched to the core, and an oppositely charged canopy （PEG-substituted tertiary amines） to balance the corona. By selecting proper canopy such as surface-functionalized, silica can behave viscous liquid in the absence of any solvent at room temperature. DSC results indicated the melting temperature and glass transition of the derivatives were slightly lower than those of the neat polymer canopy, indicating strong interaction between the core and PEG-substituted tertiary amine.展开更多
A simple and reproducible method for the rapid extraction and determination of trace amounts of copper（Ⅱ） ions using octadecyl-bonded silica membrane disks modified by N,N′-disalicylideneethylenediamine （DESDA） ...A simple and reproducible method for the rapid extraction and determination of trace amounts of copper（Ⅱ） ions using octadecyl-bonded silica membrane disks modified by N,N′-disalicylideneethylenediamine （DESDA） and atomic absorption spectrometry was presented. The method is based on complex formation on the surface of the ENVI-18 DISK^TM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effects of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about be 1000 mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be （389±4） μg for Cu^2＋. The limit of detection of the proposed method is 5 ng per liter. The method was applied to the extraction and recovery of copper in different water samples.展开更多
基金Funded by the National Natural Science Foundation of China(No.51003084)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘A series of silica nanoscale materials（NIMs） were prepared through a facile acid-base neutralization. These silica derivatives consist of a nanosilica core, a charged corana（sulfonic acid SIT） attatched to the core, and an oppositely charged canopy （PEG-substituted tertiary amines） to balance the corona. By selecting proper canopy such as surface-functionalized, silica can behave viscous liquid in the absence of any solvent at room temperature. DSC results indicated the melting temperature and glass transition of the derivatives were slightly lower than those of the neat polymer canopy, indicating strong interaction between the core and PEG-substituted tertiary amine.
文摘A simple and reproducible method for the rapid extraction and determination of trace amounts of copper（Ⅱ） ions using octadecyl-bonded silica membrane disks modified by N,N′-disalicylideneethylenediamine （DESDA） and atomic absorption spectrometry was presented. The method is based on complex formation on the surface of the ENVI-18 DISK^TM disks followed by stripping of the retained species by minimum amounts of appropriate organic solvents. The elution is efficient and quantitative. The effects of potential interfering ions, pH, ligand amount, stripping solvent, and sample flow rate were also investigated. Under the optimal experimental conditions, the break-through volume was found to about be 1000 mL providing a preconcentration factor of 500. The maximum capacity of the disks was found to be （389±4） μg for Cu^2＋. The limit of detection of the proposed method is 5 ng per liter. The method was applied to the extraction and recovery of copper in different water samples.
