The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer ca...The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer can make a-cristobalite convertto a-tridymite whose bulk effect is small. The crystal structure and its amount were investigated with XRD technique. The influence of different amounts of MnO2 on thecrystal structure and polycrystal transformation, and that of crystal structure on theproperties of kiln furniture were studied. The best proportion of MnO2 added was determined to be 2.0%.展开更多
TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carder to discuss the influence of pH value of gel precursor on microstructure an...TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carder to discuss the influence of pH value of gel precursor on microstructure and activity of photocatalyst in the process of synthesizing nano-TiO2 by using sol-gel method, the purpose of which is to provide fundamental data for the recycle of photocatalytic material. Under the irradiation of ultraviolet light, the photocatalytic degradation rate of methyl orange solution was used to characterize the photocatalytic activity of the sample. The specific surface area of the sample was tested by N2 desorption method, crystal form of TiO2 was analyzed by X-ray powder diffraction, and the microtopography of the sample was observed by scanning electron microscopy. The experimental results showed that the acidity of gel precursor could greatly affect the specific surface area and photocatalytic activity of the photocatalyst, and the optimum pH value of the precursor was determined as 2.0, and at this time the specific surface area of photocatalyst could reach 34.0 m^2/g. In the sample, the proporticn of anatase to rutile is 7：3, which makes l0 mg·L^-1 methyl orange solution fade after irradiation by 15W ultraviolet light for 24 h, and the degradation rate might be up to 98.1%.展开更多
以铁合金厂回收的硅灰粉尘和工业氧化铝为主要原料合成莫来石材料,主要探讨烧结温度对莫来石晶相结构和显微结构的影响,从而选择最佳的烧结温度。采用X射线粉末衍射分析(X-Ray diffraction,XRD),扫描电镜(Scanning electron microscopy,...以铁合金厂回收的硅灰粉尘和工业氧化铝为主要原料合成莫来石材料,主要探讨烧结温度对莫来石晶相结构和显微结构的影响,从而选择最佳的烧结温度。采用X射线粉末衍射分析(X-Ray diffraction,XRD),扫描电镜(Scanning electron microscopy,SEM)及相关分析软件,如:Philipsplus,Rietveld quantification等表征得到的莫来石。结果表明:1500℃烧结的样品中莫来石含量最高,达93%,合成的莫来石以固溶体Al4.6Si1.4O9.7的形式存在,在扫描电镜下观察,多以细粒状产出。展开更多
文摘The properties of SiC kiln furniture bonded with fine silicon powderare related to the bonder’s crystal structure. At high temperature, it will crystallize ina-cristobalite with great bulk effect. MnO2 mineralizer can make a-cristobalite convertto a-tridymite whose bulk effect is small. The crystal structure and its amount were investigated with XRD technique. The influence of different amounts of MnO2 on thecrystal structure and polycrystal transformation, and that of crystal structure on theproperties of kiln furniture were studied. The best proportion of MnO2 added was determined to be 2.0%.
基金Fujian Science and Technology Administration (2004I003 and 2006N0037)
文摘TiO2 photocatalyst was supported with tetrabutyl titanate sol as precursor and fine silicon powder obtained from ferroalloys factory as carder to discuss the influence of pH value of gel precursor on microstructure and activity of photocatalyst in the process of synthesizing nano-TiO2 by using sol-gel method, the purpose of which is to provide fundamental data for the recycle of photocatalytic material. Under the irradiation of ultraviolet light, the photocatalytic degradation rate of methyl orange solution was used to characterize the photocatalytic activity of the sample. The specific surface area of the sample was tested by N2 desorption method, crystal form of TiO2 was analyzed by X-ray powder diffraction, and the microtopography of the sample was observed by scanning electron microscopy. The experimental results showed that the acidity of gel precursor could greatly affect the specific surface area and photocatalytic activity of the photocatalyst, and the optimum pH value of the precursor was determined as 2.0, and at this time the specific surface area of photocatalyst could reach 34.0 m^2/g. In the sample, the proporticn of anatase to rutile is 7：3, which makes l0 mg·L^-1 methyl orange solution fade after irradiation by 15W ultraviolet light for 24 h, and the degradation rate might be up to 98.1%.
文摘以铁合金厂回收的硅灰粉尘和工业氧化铝为主要原料合成莫来石材料,主要探讨烧结温度对莫来石晶相结构和显微结构的影响,从而选择最佳的烧结温度。采用X射线粉末衍射分析(X-Ray diffraction,XRD),扫描电镜(Scanning electron microscopy,SEM)及相关分析软件,如:Philipsplus,Rietveld quantification等表征得到的莫来石。结果表明:1500℃烧结的样品中莫来石含量最高,达93%,合成的莫来石以固溶体Al4.6Si1.4O9.7的形式存在,在扫描电镜下观察,多以细粒状产出。
