The characteristics of the zeolite modified by microwave and sodium acetate and its sorption of ammonia-nitrogen from simulated water sample were investigated.The results show that the modified zeolite by microwave-so...The characteristics of the zeolite modified by microwave and sodium acetate and its sorption of ammonia-nitrogen from simulated water sample were investigated.The results show that the modified zeolite by microwave-sodium acetate(SMMZ)has a high sorption efficiency and removal performance.The ammonia-nitrogen removal rate of SMMZ reaches 92.90%.The surface of SMMZ becomes loose and some pores appear,the specific surface area,total pore volume and average pore diameter increase after modification.Compared to the natural zeolite,SMMZ has a more concentrated pore size distribution in the range of 0-10 nm.The cation exchange capacity(CEC)of SMMZ is higher than that of the natural zeolite.And the ammonia nitrogen removal rate is consistent with the change of CEC.The SMMZ possesses rapid sorption and slow balance characteristics and ammonia-nitrogen sorption is consistent with both Langmuir adsorption isotherm model and Freundlich adsorption isotherm model.The adsorption kinetics of ammonia-nitrogen follows the pseudo-second order kinetic model.展开更多
The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） ...The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.展开更多
Black carrots （Daucus earota L. spp. sativus. ） were fermented for 4 weeks by using six different starter dough formulations. Some of the samples were pasteurized to detemaine the effects of heat treatment on fermen...Black carrots （Daucus earota L. spp. sativus. ） were fermented for 4 weeks by using six different starter dough formulations. Some of the samples were pasteurized to detemaine the effects of heat treatment on fermentation. Fermentation was followed by physicochemical and microbiological analysis. Some characteristics such as dry matter, crude fiber, water soluble extract, alcohol soluble extract, ether soluble extract, crude energy, total sugar, pH, salt and colour values and mineral contents of black carrot were determined. In the beginning of the fermentation, dry matter is highest in the brines with coriandrium and dry matter of the other brines are close to each other and lower than that of the brines with coriander. The number of Lactic acid bacteria, total bacteria, moulds-yeasts and coliform bacteria decreased through the end of fermentation. Heat treatment had a considerable effect on microbial growth. The microbial growth was higher in the nnpastenrized samples. Total bacteria number reached the highest level for the pasteurized samples （ 104 cfu/mL - 105 cfu/mL ） and for the unpasteurized samples （106 cfu/mL - 107 cfu/mL） in the second day. After the fermentation, sensory analyses were carried out to determine the storage stability of the last products. While ＂a＂ value increased, ＂b＂ and ＂L＂ values decreased during storage time. Yoghurt inoculated brine were preferred from the colour, odour and acceptability points of view.展开更多
Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared...Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, water contact angle assays, platelet-adhesion and hemolytic rate assays. Results: The results showed that the two MWCNTs had a similar surface topography and MWCNTs-OH were functionalized with hydroxyl groups on their surfaces. Water contact angle assays indicated that MWCNTs were hydrophobic materials, whereas MWCNTs-OH was hydrophilic. The platelet-adhesion assays displayed that the platelet-adhesion rate of MWCNTs-OH was much lower than MWCNTs. The hemolytic rate assays showed that the hemolytic rates of both MWCNTs were lower than the standard value of 5%. Conclusion: MWCNTs-OH shows superior anticoagulant capacity over MWCNTs. Both MWCNTs and MWCNTs-OH are nonhemolytic materials.展开更多
Oxidative damage to plasmid DNA induced by airborne PM10 （particulate matter with an aerodynamic diameter of 10 μm or less） is caused by the bioavailable （i.e., soluble） heavy metals on the particle surface. Howe...Oxidative damage to plasmid DNA induced by airborne PM10 （particulate matter with an aerodynamic diameter of 10 μm or less） is caused by the bioavailable （i.e., soluble） heavy metals on the particle surface. However, quantitative analyses of the links between PM10 and oxidative damage are limited. In this study, plasmid DNA assay and ICP-MS were applied to study oxidative capacity and trace element compositions, respectively, of summer and winter PM10 samples collected at several sites （Sun Yat Sen Municipal Park （SYSP） and Av. de Horta e Costa （AHC） on the Macao peninsula and Macao University on Tai- pa Island （TI）） in Macao. At AHC and TI, the oxidative capacity of PM10 collected in winter was higher than that collected in summer, for both the whole sample and the water-soluble fraction. In contrast, no seasonal variation was noted at SYSP. PMI0 exhibited the highest oxidative capacity at SYSP and lowest oxidative capacity at TI in both seasons, demonstrating that the PMl0 collected on the Macao peninsula had a higher toxicity than that from Taipa Island. ICP-MS analyses revealed that the concentrations of total analyzed trace elements and their water-soluble components in PMI0 from TI and AHC were higher in winter than in summer, whereas SYSP displayed the opposite trend. The extents of oxidative damage induced by the wa- ter-soluble fractions and intact whole particles were generally similar, implying that the oxidative damage caused by particles in Macao resulted mainly from the water-soluble fraction. The oxidative capacities of PM10 were positively correlated with both whole and soluble Zn at the 95% confidence level, indicating that Zn was the major element responsible for the oxidative damage caused by particles in Macao. Other heavy metals, such as Cr, Cu, Cd, Ni, As, and Pb, also exhibited elevated concen- trations, and the potential health impacts of these metals should be considered.展开更多
Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres ch...Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres changed into SnaO4 nanospheres covered with single-crystalline nanoplates having a high BET surface area of ca. 55.05 m^2·g^-1 and a band gap of ca. 2.25 eV. Small amounts （0.05 g） of the hierarchical Sn3O4 nanostructures completely decomposed a 30% methyl orange （MO） solution in 100 mL deionized water within 15 min under one sun condition （UV ＋ visible light）. The Sn3O4 photocatalyst exhibited a fast decomposition rate of 1.73 ×10^-1 min^-1, which is a 90.86% enhancement relative to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn3O4 nanostructures is attributed to its ability to absorb visible light and its high surface-to-volume ratio.展开更多
基金Project(51174017) supported by the National Natural Science Foundation of China
文摘The characteristics of the zeolite modified by microwave and sodium acetate and its sorption of ammonia-nitrogen from simulated water sample were investigated.The results show that the modified zeolite by microwave-sodium acetate(SMMZ)has a high sorption efficiency and removal performance.The ammonia-nitrogen removal rate of SMMZ reaches 92.90%.The surface of SMMZ becomes loose and some pores appear,the specific surface area,total pore volume and average pore diameter increase after modification.Compared to the natural zeolite,SMMZ has a more concentrated pore size distribution in the range of 0-10 nm.The cation exchange capacity(CEC)of SMMZ is higher than that of the natural zeolite.And the ammonia nitrogen removal rate is consistent with the change of CEC.The SMMZ possesses rapid sorption and slow balance characteristics and ammonia-nitrogen sorption is consistent with both Langmuir adsorption isotherm model and Freundlich adsorption isotherm model.The adsorption kinetics of ammonia-nitrogen follows the pseudo-second order kinetic model.
基金Supported by the National Basic Research Program of China (2007CB613507)
文摘The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.
文摘Black carrots （Daucus earota L. spp. sativus. ） were fermented for 4 weeks by using six different starter dough formulations. Some of the samples were pasteurized to detemaine the effects of heat treatment on fermentation. Fermentation was followed by physicochemical and microbiological analysis. Some characteristics such as dry matter, crude fiber, water soluble extract, alcohol soluble extract, ether soluble extract, crude energy, total sugar, pH, salt and colour values and mineral contents of black carrot were determined. In the beginning of the fermentation, dry matter is highest in the brines with coriandrium and dry matter of the other brines are close to each other and lower than that of the brines with coriander. The number of Lactic acid bacteria, total bacteria, moulds-yeasts and coliform bacteria decreased through the end of fermentation. Heat treatment had a considerable effect on microbial growth. The microbial growth was higher in the nnpastenrized samples. Total bacteria number reached the highest level for the pasteurized samples （ 104 cfu/mL - 105 cfu/mL ） and for the unpasteurized samples （106 cfu/mL - 107 cfu/mL） in the second day. After the fermentation, sensory analyses were carried out to determine the storage stability of the last products. While ＂a＂ value increased, ＂b＂ and ＂L＂ values decreased during storage time. Yoghurt inoculated brine were preferred from the colour, odour and acceptability points of view.
基金National Natural Science Foundation of Chinagrant number:11075116 and 51272176+3 种基金National Basic Research Program of China(973 Program)grant number:2012CB933604Open Research Fund of the State Key Laboratory of Bioelectronics,Southeast Universitythe Key Laboratory of Beam Technology and Material Modification of the Ministry of Education,Beijing Normal University
文摘Objective: To study and compare the hemocompatibility of MWCNTs and hydroxyl modificated MWCNTs (MWCNTs-OH). Methods: MWCNTs and MWCNTs-OH were characterized by scanning electron microscope, Fourier transform infrared spectroscopy, water contact angle assays, platelet-adhesion and hemolytic rate assays. Results: The results showed that the two MWCNTs had a similar surface topography and MWCNTs-OH were functionalized with hydroxyl groups on their surfaces. Water contact angle assays indicated that MWCNTs were hydrophobic materials, whereas MWCNTs-OH was hydrophilic. The platelet-adhesion assays displayed that the platelet-adhesion rate of MWCNTs-OH was much lower than MWCNTs. The hemolytic rate assays showed that the hemolytic rates of both MWCNTs were lower than the standard value of 5%. Conclusion: MWCNTs-OH shows superior anticoagulant capacity over MWCNTs. Both MWCNTs and MWCNTs-OH are nonhemolytic materials.
基金supported by the National Natural Science Foundation of China (Grant No. 41030213)the Macao Foundation for Development of Science and Technology (Grant No. 023/2006/A)
文摘Oxidative damage to plasmid DNA induced by airborne PM10 （particulate matter with an aerodynamic diameter of 10 μm or less） is caused by the bioavailable （i.e., soluble） heavy metals on the particle surface. However, quantitative analyses of the links between PM10 and oxidative damage are limited. In this study, plasmid DNA assay and ICP-MS were applied to study oxidative capacity and trace element compositions, respectively, of summer and winter PM10 samples collected at several sites （Sun Yat Sen Municipal Park （SYSP） and Av. de Horta e Costa （AHC） on the Macao peninsula and Macao University on Tai- pa Island （TI）） in Macao. At AHC and TI, the oxidative capacity of PM10 collected in winter was higher than that collected in summer, for both the whole sample and the water-soluble fraction. In contrast, no seasonal variation was noted at SYSP. PMI0 exhibited the highest oxidative capacity at SYSP and lowest oxidative capacity at TI in both seasons, demonstrating that the PMl0 collected on the Macao peninsula had a higher toxicity than that from Taipa Island. ICP-MS analyses revealed that the concentrations of total analyzed trace elements and their water-soluble components in PMI0 from TI and AHC were higher in winter than in summer, whereas SYSP displayed the opposite trend. The extents of oxidative damage induced by the wa- ter-soluble fractions and intact whole particles were generally similar, implying that the oxidative damage caused by particles in Macao resulted mainly from the water-soluble fraction. The oxidative capacities of PM10 were positively correlated with both whole and soluble Zn at the 95% confidence level, indicating that Zn was the major element responsible for the oxidative damage caused by particles in Macao. Other heavy metals, such as Cr, Cu, Cd, Ni, As, and Pb, also exhibited elevated concen- trations, and the potential health impacts of these metals should be considered.
文摘Hierarchical tin（Ⅲ） oxide, Sn3O4, nanospheres were synthesized via hydrothermal reaction under strongly acidic ambient conditions. The morphology of Sn3O4 varied with decreasing pH. The prickly SnaO4 nanospheres changed into SnaO4 nanospheres covered with single-crystalline nanoplates having a high BET surface area of ca. 55.05 m^2·g^-1 and a band gap of ca. 2.25 eV. Small amounts （0.05 g） of the hierarchical Sn3O4 nanostructures completely decomposed a 30% methyl orange （MO） solution in 100 mL deionized water within 15 min under one sun condition （UV ＋ visible light）. The Sn3O4 photocatalyst exhibited a fast decomposition rate of 1.73 ×10^-1 min^-1, which is a 90.86% enhancement relative to that of the commercially available P25 photocatalyst. The high photocatalytic activity of the hierarchical Sn3O4 nanostructures is attributed to its ability to absorb visible light and its high surface-to-volume ratio.
