π-π Stacking in the 2,4,6-tris(4-pyridyl)-1,3,5-triazine aromatic nitrogen-containing ligand and its metal-ligand complex Zn(TPT)2(H2O)4(OH)2 1 has been investigated by single-crystal X-ray diffraction analy...π-π Stacking in the 2,4,6-tris(4-pyridyl)-1,3,5-triazine aromatic nitrogen-containing ligand and its metal-ligand complex Zn(TPT)2(H2O)4(OH)2 1 has been investigated by single-crystal X-ray diffraction analyses. The stacking mode of the ligand changes from the offset conformation to a perfect face-to-face alignment with the coordination to the zinc centers. The structure features are correlated with their solid-state luminescence properties. With excitation at 360 nm, free TPT ligand gives a strong fluorescent emission at 455 nm and the ligand-centered emission of the metal-ligand complex occurs at the same wavelength with lower emission intensity. The distance between the aromatic rings responds to the difference of luminescence characters.展开更多
利用高效凝胶色谱(high performance gel permeation chromatography,HPGPC)分析桑叶多糖两个组分MPL1和MPL2的重均分子质量分别为11800D和7630D,利用GC分析MPL1和MPL2是由D-果糖(D-Flu)、L-阿拉伯糖(L-Ara)、L-鼠李糖(L-Rha)、D-木糖(D...利用高效凝胶色谱(high performance gel permeation chromatography,HPGPC)分析桑叶多糖两个组分MPL1和MPL2的重均分子质量分别为11800D和7630D,利用GC分析MPL1和MPL2是由D-果糖(D-Flu)、L-阿拉伯糖(L-Ara)、L-鼠李糖(L-Rha)、D-木糖(D-Xyl)和D-葡萄糖(D-Glu)5种单糖组成,其物质的量比分别为58:9.9:5.8:5.1:21.2和45:6.74:17.2:7.3:24.1。而通过高碘酸氧化和Smith降解反应的方法得到MPL1和MPL2的主链是由1→3位键合的糖基组成,支链为1→2位键合的糖基组成。红外光谱分析桑叶多糖中存在α构型的C—H吸收峰。展开更多
系统级封装(System In a Package,SiP)器件结构及功能具有复杂性,对该类器件的可靠性评价还缺乏统一的标准和规范,随着新研SiP器件的大量出现,缺乏相应评价手段与工程应用需求等矛盾日显突出。为此,开展对SiP器件典型失效模式与失效机...系统级封装(System In a Package,SiP)器件结构及功能具有复杂性,对该类器件的可靠性评价还缺乏统一的标准和规范,随着新研SiP器件的大量出现,缺乏相应评价手段与工程应用需求等矛盾日显突出。为此,开展对SiP器件典型失效模式与失效机理分析工作,确定器件薄弱环节,并设计SiP功能运行状态监测系统,实现状态实时监测,避免了无法准确掌握器件试验过程中失效情况。为该类器件提供可靠性评价手段,提高器件使用可靠性。展开更多
基金Financially supported by NNSFC (No. 20701014)NSFFPC (No. 2003 F006)the SRP Program of SCUT
文摘π-π Stacking in the 2,4,6-tris(4-pyridyl)-1,3,5-triazine aromatic nitrogen-containing ligand and its metal-ligand complex Zn(TPT)2(H2O)4(OH)2 1 has been investigated by single-crystal X-ray diffraction analyses. The stacking mode of the ligand changes from the offset conformation to a perfect face-to-face alignment with the coordination to the zinc centers. The structure features are correlated with their solid-state luminescence properties. With excitation at 360 nm, free TPT ligand gives a strong fluorescent emission at 455 nm and the ligand-centered emission of the metal-ligand complex occurs at the same wavelength with lower emission intensity. The distance between the aromatic rings responds to the difference of luminescence characters.
文摘利用高效凝胶色谱(high performance gel permeation chromatography,HPGPC)分析桑叶多糖两个组分MPL1和MPL2的重均分子质量分别为11800D和7630D,利用GC分析MPL1和MPL2是由D-果糖(D-Flu)、L-阿拉伯糖(L-Ara)、L-鼠李糖(L-Rha)、D-木糖(D-Xyl)和D-葡萄糖(D-Glu)5种单糖组成,其物质的量比分别为58:9.9:5.8:5.1:21.2和45:6.74:17.2:7.3:24.1。而通过高碘酸氧化和Smith降解反应的方法得到MPL1和MPL2的主链是由1→3位键合的糖基组成,支链为1→2位键合的糖基组成。红外光谱分析桑叶多糖中存在α构型的C—H吸收峰。
文摘系统级封装(System In a Package,SiP)器件结构及功能具有复杂性,对该类器件的可靠性评价还缺乏统一的标准和规范,随着新研SiP器件的大量出现,缺乏相应评价手段与工程应用需求等矛盾日显突出。为此,开展对SiP器件典型失效模式与失效机理分析工作,确定器件薄弱环节,并设计SiP功能运行状态监测系统,实现状态实时监测,避免了无法准确掌握器件试验过程中失效情况。为该类器件提供可靠性评价手段,提高器件使用可靠性。