研究了微波辐射对硫酸催化稻草水解的促进作用。考察了微波辐射功率、辐射时间、硫酸质量分数及每升硫酸溶液中稻草添加量对还原糖得率的影响。与常规酸水解比较,微波辐射可显著加快水解速率,缩短糖化时间。采用正交试验法对微波辐射下...研究了微波辐射对硫酸催化稻草水解的促进作用。考察了微波辐射功率、辐射时间、硫酸质量分数及每升硫酸溶液中稻草添加量对还原糖得率的影响。与常规酸水解比较,微波辐射可显著加快水解速率,缩短糖化时间。采用正交试验法对微波辐射下稻草硫酸水解条件进行了优化,最佳条件为:微波功率280 W,辐射时间30 m in,硫酸质量分数25%,每升硫酸溶液中稻草添加量30 g,还原糖得率达到26.45%。展开更多
Using La2(SO4)3 and the active carbon powder as reactants, La2O2S∶Mn2+ red phosphor was synthesized by microwave radiation method. The phosphor was characterized by means of X-ray diffraction (XRD), scanning electron...Using La2(SO4)3 and the active carbon powder as reactants, La2O2S∶Mn2+ red phosphor was synthesized by microwave radiation method. The phosphor was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), laser-diffraction size analyzer and fluorospectrophotometer. The XRD analysis showed that the phosphor was pure phase La2O2S. The phosphor of La2O2S∶Mn2+ showed hexagonal crystal structure with diverse shapes, such as spherical and rod, with average particle size of 10.22 μm. The emission and excitation spectra of the phosphor were determined by fluorospectrophotometer and the results showed that the excitation spectrum of the phosphor under 600 nm emission wavelength was excitation bands between 250 nm and 350 nm with a peak value of 303 nm. Then ,when exicited under UV 303 nm, the phosphor showed broad band emission of 550~700 nm with a peak at 607 nm. In addition, the optimal effects were obtained for the phosphor preparation when the concentration of the activator Mn2+ was xMn=0.01, the ratio of C and O (nC / nO) in the reactants was 0.6∶1, and the time of reaction was about 1 h. La2O2S∶Mn2+ has strong absorption of UV spectrum and can emit bright red light.展开更多
文摘研究了微波辐射对硫酸催化稻草水解的促进作用。考察了微波辐射功率、辐射时间、硫酸质量分数及每升硫酸溶液中稻草添加量对还原糖得率的影响。与常规酸水解比较,微波辐射可显著加快水解速率,缩短糖化时间。采用正交试验法对微波辐射下稻草硫酸水解条件进行了优化,最佳条件为:微波功率280 W,辐射时间30 m in,硫酸质量分数25%,每升硫酸溶液中稻草添加量30 g,还原糖得率达到26.45%。
文摘Using La2(SO4)3 and the active carbon powder as reactants, La2O2S∶Mn2+ red phosphor was synthesized by microwave radiation method. The phosphor was characterized by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), laser-diffraction size analyzer and fluorospectrophotometer. The XRD analysis showed that the phosphor was pure phase La2O2S. The phosphor of La2O2S∶Mn2+ showed hexagonal crystal structure with diverse shapes, such as spherical and rod, with average particle size of 10.22 μm. The emission and excitation spectra of the phosphor were determined by fluorospectrophotometer and the results showed that the excitation spectrum of the phosphor under 600 nm emission wavelength was excitation bands between 250 nm and 350 nm with a peak value of 303 nm. Then ,when exicited under UV 303 nm, the phosphor showed broad band emission of 550~700 nm with a peak at 607 nm. In addition, the optimal effects were obtained for the phosphor preparation when the concentration of the activator Mn2+ was xMn=0.01, the ratio of C and O (nC / nO) in the reactants was 0.6∶1, and the time of reaction was about 1 h. La2O2S∶Mn2+ has strong absorption of UV spectrum and can emit bright red light.
