The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powd...The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powder X ray diffractometry.According to our measurements with X ray diffraction,this material belongs to orthorhombic system with its lattice contants:a=1.4824nm,b=1.1902nm,c=1.1042nm,that are consistent with space group D 4 2 P2 12 12 1(No.19).The emission and excitation spectra were also measured.The luminescence properties of Eu 3+ doped Na 24 As 2Mo 22 O 83 and energy transfer mechanism were discussed.展开更多
A new triterpenoid. 3 beta. 4 beta. 23-trihydroxy-24, 30-dinorolean-12. 20(29)-dien-28-oic acid. together with five known compounds. 2 alpha. 3 beta. 23-trihydroxy-12-oleanen-28-oic acid-beta -D-glucose glucopyranosyl...A new triterpenoid. 3 beta. 4 beta. 23-trihydroxy-24, 30-dinorolean-12. 20(29)-dien-28-oic acid. together with five known compounds. 2 alpha. 3 beta. 23-trihydroxy-12-oleanen-28-oic acid-beta -D-glucose glucopyranosyl ester. palbinone. 2-hydroxy-benzoic acid, vanillic acid. syringic acid. were isolated from the roots of Paeonia delavayi Franch. Their structures were characterized by spectral analysis.展开更多
文摘The Eu 3+ doped Na 24 As 2Mo 22 O 83 phosphor was prepared by solid state reaction from Na 3AsO 4·12H 2O?Na 2MoO 4·2H 2O and MoO 3,and characterized by using elemental analysis,infrared spectroscopy and powder X ray diffractometry.According to our measurements with X ray diffraction,this material belongs to orthorhombic system with its lattice contants:a=1.4824nm,b=1.1902nm,c=1.1042nm,that are consistent with space group D 4 2 P2 12 12 1(No.19).The emission and excitation spectra were also measured.The luminescence properties of Eu 3+ doped Na 24 As 2Mo 22 O 83 and energy transfer mechanism were discussed.
文摘目的:对自行编制的食物频率问卷进行效度检验,探究其是否可用于孕期妇女的膳食调查及规模人群营养流行病学调查。方法:以在孕早期(10~13w^(+6) d)完成食物频率(FFQ)调查,并收集到3天24小时膳食回顾(3days 24HR)数据的111名孕妇作为调查对象。采用Wilcoxon配对秩和检验比较两种方法摄入量之间的差异;采用Spearman相关系数评估两种方法的一致性程度;采用Bland-Altman图用于比较两种方法所得平均总能量和宏量营养素摄入量的差异。结果:使用FFQ调查与3 days 24HR调查对热量、主食及蔬菜的摄入量估计无统计学差异。热量、三大宏量营养素的Spearman相关系数范围为0.249(脂肪)~0.529(蛋白质)。除主食、薯类、菌藻类及水果外,其他食物组的相关性均有统计学意义,Spearman相关系数范围为0.180(粗粮)~0.578(奶制品)。BlandAltman图显示,热量、蛋白质及脂肪的比值均在1附近。结论:本研究设计的较为短小的食物频率问卷的效度较好,可以用于孕期孕妇的膳食调查,也可用于开展大规模人群营养流行病学调查。
文摘A new triterpenoid. 3 beta. 4 beta. 23-trihydroxy-24, 30-dinorolean-12. 20(29)-dien-28-oic acid. together with five known compounds. 2 alpha. 3 beta. 23-trihydroxy-12-oleanen-28-oic acid-beta -D-glucose glucopyranosyl ester. palbinone. 2-hydroxy-benzoic acid, vanillic acid. syringic acid. were isolated from the roots of Paeonia delavayi Franch. Their structures were characterized by spectral analysis.