Predispersed solvent extraction (PDSE) is a new method for separating solutes from aqueous solution by solvent extraction and one which has shown promise for extraction from extremely dilute solution very efficient an...Predispersed solvent extraction (PDSE) is a new method for separating solutes from aqueous solution by solvent extraction and one which has shown promise for extraction from extremely dilute solution very efficient and very quick. The use of colloidal liquid aphrons in predispersed solvent extraction may ameliorate the problems such as emulsion formation, reduction of interfacial mass transfer and low interfacial mass transfer areas in solvent extraction process. In present paper, colloidal liquid aphrons are successfully generated using kerosene as a solvent, tributyl phosphate(TBP) as an extractant, sodium dodecyl benzene sulphate(SDBS) as surfactant in aqueous phase and Tween-80 in oil phase. Extraction of phenol from dilute solution was studied by using colloidal liquid aphrons and colloidal gas aphrons in a semi-batch extraction column. It has been found that the PDSE process is more suitable for extraction of dilute solutions. It has also been discovered that the PDSE process has a great advantage over traditional single-stage extraction process.展开更多
AIM: To establish a model of islet-ductal cell transdifferen-tiation to identify the transdifferentiated cells. METHODS: Collagen was extracted from rat tail at first. Purified rat islets were divided into three group...AIM: To establish a model of islet-ductal cell transdifferen-tiation to identify the transdifferentiated cells. METHODS: Collagen was extracted from rat tail at first. Purified rat islets were divided into three groups, embedded in collagen gel and incubated respectively in DMEM/F12 alone (control group), DMEM/F12 plus epidermal growth factor (EGF), DMEM/F12 plus EGF and cholera toxin (CT). Transdifferentiation was proved by microscopy, RT-PCR, immunohistochemistry and RIA. RESULTS: Islets embedded in collagen gel plus EGF and CT were cystically transformed and could express new gene cytokeratin 19 while still maintaining the expression of insulin and Pdx-1 genes. Immunohistochemistry demonstrated that the protein of cytokeratin 19 was only expressed in the third group. The insulin content secreted by islets in the third group decreased significantly during the transdiffe-rentiation. CONCLUSION: CT is a crucial factor for the islet-ductal cell transdifferentiation.展开更多
Nano hydroxyapatite (HA) crystals were prepared and dispersed in water to form HA sol by simple methods. The cytotoxicity of the sols were tested by MTT assay and lymphocytotoxicity test. Results show that the average...Nano hydroxyapatite (HA) crystals were prepared and dispersed in water to form HA sol by simple methods. The cytotoxicity of the sols were tested by MTT assay and lymphocytotoxicity test. Results show that the average secondary particle size of the sol containing uncalcined HA crystals is around 750 nm, within micrograde; while the sol of calcined HA contains over 88% nanoparticles with the size between 65～86 nm, in which nano HA crystals are highly dispersed. Both the HA sols have no toxicity on the proliferation of 3T3 cells and lymphocytes. It demonstrates that the nano sol is safe for the application of drug delivery.展开更多
1 INTRODUCTIONMicroemulsion and micelle systems are wide-spread in the industry and agriculture applications,e.g.the petroleum exploitation,food industry chemical engineering and biological engineering,but so far,thei...1 INTRODUCTIONMicroemulsion and micelle systems are wide-spread in the industry and agriculture applications,e.g.the petroleum exploitation,food industry chemical engineering and biological engineering,but so far,their properties are still not very well understood.Both micelle and microemulsion systems are dispersed systems and consist of the aggregationsof the surfactant.The difference between them is that there is dispered liquid phase in the coreof the aggregation in the case of the microemulsion,but in the micelle there is not any展开更多
In this article, AHPS (3 - allyloxy- 2 -hydrory- 1 -Propanesulfonate salt) wassynthesized to use in emulsifier-Ne emulsion polymerization of BA/BMa/MMA systemfor high solid content latexes. Storage stability klow beha...In this article, AHPS (3 - allyloxy- 2 -hydrory- 1 -Propanesulfonate salt) wassynthesized to use in emulsifier-Ne emulsion polymerization of BA/BMa/MMA systemfor high solid content latexes. Storage stability klow behavior of the latexes,morphology of the obtained latex particles, dynamic viscoelastic behavior, tensilestrength and water resistance properties of the resulted copolymers were investigated.The experimental results show that with the addition of AHPS, stability of the emulsionis greatly improved that there appears no apparent precipitation dunring thepolymerization and storage at room temperature for 6 months and at -10℃ for fourmonths. Flow of the latexes follows the Bingham body laws, diameter of the latexparticles is about 0.6μn, of which is larger than that of by conventional emulsionpolymerization(0.12μm). In addition, not only water resistance of the copolymersobtained by emulsifier-free emulsion polymerization is greatly improved, but alsotensile strength is obviously enhanced.展开更多
The speed of sound in quark matter is an important physical quantity for studying the properties and the spacetime evolution of quark-gluon plasma(QGP).The behavior of the speed of sound with respect to temperature an...The speed of sound in quark matter is an important physical quantity for studying the properties and the spacetime evolution of quark-gluon plasma(QGP).The behavior of the speed of sound with respect to temperature and density can reveal to some extent the equation of state and the phase structure of QGP.Building upon the previous studies on the speed of sound in symmetric quark matter,the formulae for calculating the speed of sound in asymmetric quark matter in the temperature-density space are further derived.The PNJL model is then used to calculate the dependence of the speed of sound on isospin asymmetry.Furthermore,the relationship between the magnitude of the speed of sound and the QCD phase structure is discussed,and the regions where the acoustic equation fails are indicated under different physical conditions.It is found that the boundary of vanishing sound speed in asymmetric quark matter is smaller than that in symmetric quark matter,meaning that the range where the acoustic wave equation fails in asymmetric quark matter is smaller than that in symmetric quark matter.The results also indicate that in most of the stable phase,the speed of sound in asymmetric quark matter is slightly larger than that in symmetric quark matter.展开更多
Cluster-like Ag3PO4 nanostructures including nanoparticles, trisoctahedrons, tetrahedrons and tetrapods have been prepared by the synergetic reaction of Ag nanocrystals, phosphate anions and hydrogen peroxide. The aci...Cluster-like Ag3PO4 nanostructures including nanoparticles, trisoctahedrons, tetrahedrons and tetrapods have been prepared by the synergetic reaction of Ag nanocrystals, phosphate anions and hydrogen peroxide. The acidity and alkalinity of the reaction solution are tuned to adjust the oxidizing ability of H2O2, and thus control the final morphology. Ag nanocrystals function as a sacrificial precursor, leading to the generation of clusterqike nanostructures. Through a kinetic study, the formation of Ag3PO4 nanocrystal clusters can be understood as the conversion from Ag to AgBPO4 nanocrystals assisted by H2O2, followed by the oriented attachment of nanocrystals into cluster-like colloids with specific shapes. The as-prepared AgBPO4 nanostructures have higher photocatalytic activity than commercial TiO2 and some reported AgBPO4 microcrystals in the degradation of dyes. The catalytic activity decreases in the order nanoparticles 〉 trisoctahedrons 〉 tetrahedrons 〉 tetrapods, while the stability increases in the order nanoparticles 〈 tetrahedrons 〈 trisoctahedrons 〈 tetrapods, which can be explained by the extent of absorption of visible light and structural factors, including size and exposed crystal facets.展开更多
基金Supported by the National Natural Science Foundation of China(No.29676021 and No.29836130)
文摘Predispersed solvent extraction (PDSE) is a new method for separating solutes from aqueous solution by solvent extraction and one which has shown promise for extraction from extremely dilute solution very efficient and very quick. The use of colloidal liquid aphrons in predispersed solvent extraction may ameliorate the problems such as emulsion formation, reduction of interfacial mass transfer and low interfacial mass transfer areas in solvent extraction process. In present paper, colloidal liquid aphrons are successfully generated using kerosene as a solvent, tributyl phosphate(TBP) as an extractant, sodium dodecyl benzene sulphate(SDBS) as surfactant in aqueous phase and Tween-80 in oil phase. Extraction of phenol from dilute solution was studied by using colloidal liquid aphrons and colloidal gas aphrons in a semi-batch extraction column. It has been found that the PDSE process is more suitable for extraction of dilute solutions. It has also been discovered that the PDSE process has a great advantage over traditional single-stage extraction process.
基金Supported by the National Natural Science Foundation of China, No. 30200136
文摘AIM: To establish a model of islet-ductal cell transdifferen-tiation to identify the transdifferentiated cells. METHODS: Collagen was extracted from rat tail at first. Purified rat islets were divided into three groups, embedded in collagen gel and incubated respectively in DMEM/F12 alone (control group), DMEM/F12 plus epidermal growth factor (EGF), DMEM/F12 plus EGF and cholera toxin (CT). Transdifferentiation was proved by microscopy, RT-PCR, immunohistochemistry and RIA. RESULTS: Islets embedded in collagen gel plus EGF and CT were cystically transformed and could express new gene cytokeratin 19 while still maintaining the expression of insulin and Pdx-1 genes. Immunohistochemistry demonstrated that the protein of cytokeratin 19 was only expressed in the third group. The insulin content secreted by islets in the third group decreased significantly during the transdiffe-rentiation. CONCLUSION: CT is a crucial factor for the islet-ductal cell transdifferentiation.
基金This work is supported by Guangdong Natural Science Foundation Grant (0 2 1180 ) and the National 86 3 Project(2 0 0 1AA2 180 31)
文摘Nano hydroxyapatite (HA) crystals were prepared and dispersed in water to form HA sol by simple methods. The cytotoxicity of the sols were tested by MTT assay and lymphocytotoxicity test. Results show that the average secondary particle size of the sol containing uncalcined HA crystals is around 750 nm, within micrograde; while the sol of calcined HA contains over 88% nanoparticles with the size between 65～86 nm, in which nano HA crystals are highly dispersed. Both the HA sols have no toxicity on the proliferation of 3T3 cells and lymphocytes. It demonstrates that the nano sol is safe for the application of drug delivery.
基金Supported by the National Nature Science Foundation of China(No.29736170).
文摘1 INTRODUCTIONMicroemulsion and micelle systems are wide-spread in the industry and agriculture applications,e.g.the petroleum exploitation,food industry chemical engineering and biological engineering,but so far,their properties are still not very well understood.Both micelle and microemulsion systems are dispersed systems and consist of the aggregationsof the surfactant.The difference between them is that there is dispered liquid phase in the coreof the aggregation in the case of the microemulsion,but in the micelle there is not any
文摘In this article, AHPS (3 - allyloxy- 2 -hydrory- 1 -Propanesulfonate salt) wassynthesized to use in emulsifier-Ne emulsion polymerization of BA/BMa/MMA systemfor high solid content latexes. Storage stability klow behavior of the latexes,morphology of the obtained latex particles, dynamic viscoelastic behavior, tensilestrength and water resistance properties of the resulted copolymers were investigated.The experimental results show that with the addition of AHPS, stability of the emulsionis greatly improved that there appears no apparent precipitation dunring thepolymerization and storage at room temperature for 6 months and at -10℃ for fourmonths. Flow of the latexes follows the Bingham body laws, diameter of the latexparticles is about 0.6μn, of which is larger than that of by conventional emulsionpolymerization(0.12μm). In addition, not only water resistance of the copolymersobtained by emulsifier-free emulsion polymerization is greatly improved, but alsotensile strength is obviously enhanced.
文摘The speed of sound in quark matter is an important physical quantity for studying the properties and the spacetime evolution of quark-gluon plasma(QGP).The behavior of the speed of sound with respect to temperature and density can reveal to some extent the equation of state and the phase structure of QGP.Building upon the previous studies on the speed of sound in symmetric quark matter,the formulae for calculating the speed of sound in asymmetric quark matter in the temperature-density space are further derived.The PNJL model is then used to calculate the dependence of the speed of sound on isospin asymmetry.Furthermore,the relationship between the magnitude of the speed of sound and the QCD phase structure is discussed,and the regions where the acoustic equation fails are indicated under different physical conditions.It is found that the boundary of vanishing sound speed in asymmetric quark matter is smaller than that in symmetric quark matter,meaning that the range where the acoustic wave equation fails in asymmetric quark matter is smaller than that in symmetric quark matter.The results also indicate that in most of the stable phase,the speed of sound in asymmetric quark matter is slightly larger than that in symmetric quark matter.
文摘Cluster-like Ag3PO4 nanostructures including nanoparticles, trisoctahedrons, tetrahedrons and tetrapods have been prepared by the synergetic reaction of Ag nanocrystals, phosphate anions and hydrogen peroxide. The acidity and alkalinity of the reaction solution are tuned to adjust the oxidizing ability of H2O2, and thus control the final morphology. Ag nanocrystals function as a sacrificial precursor, leading to the generation of clusterqike nanostructures. Through a kinetic study, the formation of Ag3PO4 nanocrystal clusters can be understood as the conversion from Ag to AgBPO4 nanocrystals assisted by H2O2, followed by the oriented attachment of nanocrystals into cluster-like colloids with specific shapes. The as-prepared AgBPO4 nanostructures have higher photocatalytic activity than commercial TiO2 and some reported AgBPO4 microcrystals in the degradation of dyes. The catalytic activity decreases in the order nanoparticles 〉 trisoctahedrons 〉 tetrahedrons 〉 tetrapods, while the stability increases in the order nanoparticles 〈 tetrahedrons 〈 trisoctahedrons 〈 tetrapods, which can be explained by the extent of absorption of visible light and structural factors, including size and exposed crystal facets.
