This paper presents a method of separation of fine particles, of the order of a few microns or less, from aqueous media by flotation using colloidal gas aphrons (CGAs) generated in aqueous solutions. More than 150 exp...This paper presents a method of separation of fine particles, of the order of a few microns or less, from aqueous media by flotation using colloidal gas aphrons (CGAs) generated in aqueous solutions. More than 150 experiments were conducted to study the effects of surfactant type, surfactant concentration, CGAs flow rate, and particle concentration on the removal efficiency (fine particles of polystyrene were used as a target compound). The results indicate that CGAs, generated from cationic surfactant of hexdecyltrimethyl ammonicum bromide (HTAB) and anionic surfactant of sodium dodecylbenzne sulfonate (SDBS), are an effective method for the separation off ine particles of polystyrene from wastewater. The flotation yields are higher than 97%.展开更多
Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified w...Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified with surfactant （hexadecyl-trimethyl-ammonium bromide, CTAB） as a pore templating material. The synthesized samples were characterized by the transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption techniques. The results indicated that the mesoporous silica synthesized by using [bmim][BF4] and CTAB as mixed templates showed better mesostructural order and smaller pore size, compared with mesoporous silica materials synthesized by using single [bmim][BF4] as template under the same conditions. This indicates that the presence of surfactant can affect the microstructures of silica prepared by＇the present synthesis method.展开更多
With the development of colloid interface and enzyme technologies,enzyme-containing reversed micellar system has been receiving much attention in bioseparation and bioconversion. Because of its high efficiency,it has ...With the development of colloid interface and enzyme technologies,enzyme-containing reversed micellar system has been receiving much attention in bioseparation and bioconversion. Because of its high efficiency,it has brought new opportunities for the development of molecular biotechnology. Reversed micelles represent nano-sized aqueous droplets stabilized by surfactant amphiphiles inside the bulk organic solvents. The entrapped enzymes have enhanced activities under those conditions as suited in the lipid bilayers of biological membranes. The fundamentals of enzyme-containing reversed micellar system are described in this paper,with special emphasis on the effects of surfactants varying in concentrations and structures. The latest study progress on the surfactants application in enzyme-containing reversed micelles is reviewed. The introduction of novel functional surfactants in micellar enzymology and their future development are also discussed.展开更多
A novel copper-mediated solvothermal method was proposed for synthesizing colloidal spheres of a new composition, palladium iodide （PdI2）. Typical procedure was designed to involve the introduction of cupric chlori...A novel copper-mediated solvothermal method was proposed for synthesizing colloidal spheres of a new composition, palladium iodide （PdI2）. Typical procedure was designed to involve the introduction of cupric chloride （CuCI2） as weak oxidant. CuCI2 was found to be essential for preventing the easy formation of palladium deposits as well as facilitating the synthesis and assembly. Under the co-effect of CuC12 and the surfactant of polyvinylpyrrolidone （PVP）, neutral PdI2 colloidal spheres with narrow size distribution were successfully produced. Such ion-assisted synthetic method is believed to be prospective in producing well-constructed nanostructures.展开更多
基金Supported by the National Natural Science Foundation of China (No. 29836130, No. 29676021).
文摘This paper presents a method of separation of fine particles, of the order of a few microns or less, from aqueous media by flotation using colloidal gas aphrons (CGAs) generated in aqueous solutions. More than 150 experiments were conducted to study the effects of surfactant type, surfactant concentration, CGAs flow rate, and particle concentration on the removal efficiency (fine particles of polystyrene were used as a target compound). The results indicate that CGAs, generated from cationic surfactant of hexdecyltrimethyl ammonicum bromide (HTAB) and anionic surfactant of sodium dodecylbenzne sulfonate (SDBS), are an effective method for the separation off ine particles of polystyrene from wastewater. The flotation yields are higher than 97%.
基金ACKNOWLEDGMENTS This work was supported by the National Natural Science Foundation of China （No.50564006）, the Natural Science Foundation From Science and Technology Committee of Yunnan （No.2005E0042）, and the Specialized Research Foundation for the Doctoral Program of Higher Education of China （No.20070674001）. We also thank Academician Si-shen Xie, Institute of Physics of Chinese Academy Sciences for helping with an SEM facility.
文摘Mesoporous silica materials were synthesized via a sol-gel method employing a room temperature ionic liquid （1-butyl-3-methylimidazolium tetrafiuoroborate, [bmim][BF4]） as a new solvent medium and further modified with surfactant （hexadecyl-trimethyl-ammonium bromide, CTAB） as a pore templating material. The synthesized samples were characterized by the transmission electron microscopy, X-ray diffraction, and N2 adsorption-desorption techniques. The results indicated that the mesoporous silica synthesized by using [bmim][BF4] and CTAB as mixed templates showed better mesostructural order and smaller pore size, compared with mesoporous silica materials synthesized by using single [bmim][BF4] as template under the same conditions. This indicates that the presence of surfactant can affect the microstructures of silica prepared by＇the present synthesis method.
基金supported by the National Natural Science Foundation of China (50978087,50978088 and 51039001)the Program for Changjiang Scholars and Innovative Research Team in University (IRT0719)+1 种基金the Hu-nan Provincial Natural Science Foundation of China (10JJ7005)the Hunan Key Scientific Research Project (2009FJ1010)
文摘With the development of colloid interface and enzyme technologies,enzyme-containing reversed micellar system has been receiving much attention in bioseparation and bioconversion. Because of its high efficiency,it has brought new opportunities for the development of molecular biotechnology. Reversed micelles represent nano-sized aqueous droplets stabilized by surfactant amphiphiles inside the bulk organic solvents. The entrapped enzymes have enhanced activities under those conditions as suited in the lipid bilayers of biological membranes. The fundamentals of enzyme-containing reversed micellar system are described in this paper,with special emphasis on the effects of surfactants varying in concentrations and structures. The latest study progress on the surfactants application in enzyme-containing reversed micelles is reviewed. The introduction of novel functional surfactants in micellar enzymology and their future development are also discussed.
基金supported by the National Basic Program of China for Nanoscience and Nanotechnology (973 Program,2011CB932401)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China (20921001)
文摘A novel copper-mediated solvothermal method was proposed for synthesizing colloidal spheres of a new composition, palladium iodide （PdI2）. Typical procedure was designed to involve the introduction of cupric chloride （CuCI2） as weak oxidant. CuCI2 was found to be essential for preventing the easy formation of palladium deposits as well as facilitating the synthesis and assembly. Under the co-effect of CuC12 and the surfactant of polyvinylpyrrolidone （PVP）, neutral PdI2 colloidal spheres with narrow size distribution were successfully produced. Such ion-assisted synthetic method is believed to be prospective in producing well-constructed nanostructures.
