A sol-gel method using lauric acid as surfactant was used to synthesize Li4Ti5O12 nanocrystals with an ultra-fine particle size distribution between 120 and 250 nm.In order to obtain the electrode materials with the b...A sol-gel method using lauric acid as surfactant was used to synthesize Li4Ti5O12 nanocrystals with an ultra-fine particle size distribution between 120 and 250 nm.In order to obtain the electrode materials with the best electrochemical performance,the content of lauric acid during Li4Ti5O12 synthesis was systematically studied.The physical and electrochemical properties of the synthesized samples were characterized by X-ray diffraction（XRD）,field emission scanning electron microscopy（FESEM）,transmission electron microscopy（TEM）,laser particle size analysis,alternating current impedance（AC） and galvanostatic charge-discharge experiments.The highly dispersed Li4Ti5O12 nanocrystals obtained at 800 ℃ for 10 h can deliver a specific capacity of 163.3 mA-h/g at 1C rate without obvious capacity fade up to 50 cycles.The results suggest that well dispersed Li4Ti5O12 nanocrystals shorten the Li-ion diffusion length and enhance the electrochemical kinetics of the samples,which are very crucial to high rate capability.展开更多
Biolatex, a new type of paper coating adhesive that has been developed in recent years, has mainly been used in pre-coating and middle coating, due to its advantages of decreasing the associated cost and pollution by ...Biolatex, a new type of paper coating adhesive that has been developed in recent years, has mainly been used in pre-coating and middle coating, due to its advantages of decreasing the associated cost and pollution by partly replacing petro-latex. In this paper, application of biolatex as a surface sizing agent and effects of various factors, such as titanium dioxide addition, on the properties of the sized paper were compared. The results showed that, addition of titanium dioxide to biolatex could improve the whiteness, internal bond strength, and ink absorption. Furthermore, application of the No.4 biolatex resulted in better surface strength, bond strength, and ink absorption of the sized paper than application of polyvinyl alcohol.展开更多
The effect of low methyl pectin, guar and K-carrageenan at concentrations of 1, 2 and 3% and their combinations at concentrations of 2 and 3% on quality attributes and staling of gluten free bread was studied. Among i...The effect of low methyl pectin, guar and K-carrageenan at concentrations of 1, 2 and 3% and their combinations at concentrations of 2 and 3% on quality attributes and staling of gluten free bread was studied. Among investigated samples, control （starch） bread with no added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
NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmissio...NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmission） and mass loss. Scanning electron microscopy was carried out to identify and monitor the properties of rubber degrading organism colonies. Results showed that incorporation of sago starch increased the formation and rates of propagation for microorganism colonies on NRL films with duration of biodegradation. The results also indicate the mechanism of sago starch granules utilization as sole source of energy for microbial growth. The behavior and characteristics of microorganisms involved in NRL films degradation also successfully discussed.展开更多
Our analysis of the surface aerosol and ultraviolet （UV） measurements in Pearl River Delta （PRD） region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has ...Our analysis of the surface aerosol and ultraviolet （UV） measurements in Pearl River Delta （PRD） region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations （including ozone, ultraviolet radiation, aerosol radiative parameters） and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth （AOD） and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season （October, November, December, January）, this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo （SSA） is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production.展开更多
基金Project(2007CB2097050)supported by the National Basic Research Program of ChinaProject(20803035)supported by the National Natural Science Foundation of ChinaProject supported by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),China
文摘A sol-gel method using lauric acid as surfactant was used to synthesize Li4Ti5O12 nanocrystals with an ultra-fine particle size distribution between 120 and 250 nm.In order to obtain the electrode materials with the best electrochemical performance,the content of lauric acid during Li4Ti5O12 synthesis was systematically studied.The physical and electrochemical properties of the synthesized samples were characterized by X-ray diffraction（XRD）,field emission scanning electron microscopy（FESEM）,transmission electron microscopy（TEM）,laser particle size analysis,alternating current impedance（AC） and galvanostatic charge-discharge experiments.The highly dispersed Li4Ti5O12 nanocrystals obtained at 800 ℃ for 10 h can deliver a specific capacity of 163.3 mA-h/g at 1C rate without obvious capacity fade up to 50 cycles.The results suggest that well dispersed Li4Ti5O12 nanocrystals shorten the Li-ion diffusion length and enhance the electrochemical kinetics of the samples,which are very crucial to high rate capability.
文摘Biolatex, a new type of paper coating adhesive that has been developed in recent years, has mainly been used in pre-coating and middle coating, due to its advantages of decreasing the associated cost and pollution by partly replacing petro-latex. In this paper, application of biolatex as a surface sizing agent and effects of various factors, such as titanium dioxide addition, on the properties of the sized paper were compared. The results showed that, addition of titanium dioxide to biolatex could improve the whiteness, internal bond strength, and ink absorption. Furthermore, application of the No.4 biolatex resulted in better surface strength, bond strength, and ink absorption of the sized paper than application of polyvinyl alcohol.
文摘The effect of low methyl pectin, guar and K-carrageenan at concentrations of 1, 2 and 3% and their combinations at concentrations of 2 and 3% on quality attributes and staling of gluten free bread was studied. Among investigated samples, control （starch） bread with no added
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.
文摘NRL （natural rubber latex） films with 0 （control） and 10 phr sago starch loading were buried in compost soil for 4 weeks. The biodegradation assessments were carried out through films WVT （water vapor transmission） and mass loss. Scanning electron microscopy was carried out to identify and monitor the properties of rubber degrading organism colonies. Results showed that incorporation of sago starch increased the formation and rates of propagation for microorganism colonies on NRL films with duration of biodegradation. The results also indicate the mechanism of sago starch granules utilization as sole source of energy for microbial growth. The behavior and characteristics of microorganisms involved in NRL films degradation also successfully discussed.
基金supported by National Natural Science Foundation of China (Grant Nos. 40875090, 40375002, 40775011)Natural Science Foundation of Guangdong Province (Grant No. 7035008)Tropical Marine Meteorological Science Foundation (Grant No. 200502)
文摘Our analysis of the surface aerosol and ultraviolet （UV） measurements in Pearl River Delta （PRD） region shows that the surface UV radiation is reduced by more than 50% due to high aerosol concentrations. This has important impacts on urban ecosystem and photochemistry, especially on ozone photochemical production over the region. The quantitative effect of aerosols on surface ozone is evaluated by analyzing surface observations （including ozone, ultraviolet radiation, aerosol radiative parameters） and by using radiative and chemical models. A case study shows that the aerosol concentrations and UV radiation are significantly correlated with ozone concentrations. The correlation coefficient between the aerosol optical depth （AOD） and the PM10 mass concentration is very high, with a maximum of 0.98, and the AOD and UV radiation/ozone is anti- correlated, with a correlation coefficient of-0.90. The analysis suggests that ozone productivity is significantly decreased due to the reduction of UV radiation. The noon-time ozone maximum is considerably depressed when AOD is 0.6, and is further decreased when AOD is up to 1.2 due to the reduction of ozone photochemical productivity. Because the occurring probability of aerosol optical depth for AOD550m≥0.6 and AOD340mm ≥1.0 is 47, and 55% respectively during the dry season （October, November, December, January）, this heavy aerosol condition explains the low ozone maximum that often occurs in the dry season over the Guangzhou region. The analysis also suggests that the value of single scattering albedo （SSA） is very sensitive to the aerosol radiative effect when the radiative and chemical models are applied, implying that the value of SSA needs to be carefully studied when the models are used in calculating ozone production.
