原子级分辨率的成像表征对探究材料结构与性质间的联系具有重大意义。应用像差校正的高分辨电子显微成像技术(high⁃resolution transmission electron microscopy,HRTEM)可以实现亚埃尺度分辨率的图像表征,但电子束辐照敏感材料受限于...原子级分辨率的成像表征对探究材料结构与性质间的联系具有重大意义。应用像差校正的高分辨电子显微成像技术(high⁃resolution transmission electron microscopy,HRTEM)可以实现亚埃尺度分辨率的图像表征,但电子束辐照敏感材料受限于辐照引起的结构损伤,无法用常规辐照剂量进行HRTEM成像表征。将出射波重构(exit wave reconstruction,EWR)技术应用于辐照敏感材料,一方面可以解决HRTEM图像中衬度反转的问题并提高图像分辨率至信息极限;另一方面,通过算法实现对信息的充分利用,适合于从低剂量数据中提取有效信息。采用低剂量EWR技术可以实现电子束敏感材料的原子级分辨率图像,为研究电子束辐照敏感材料提供更多可能性,也使针对出射波重构技术的研究具有更大的应用前景与科学意义。展开更多
Three new complexes of N salicylidenamino acid with Zn? have been synthesized. The compositions and structures of the obtained complexes have been characterized by elemental analyses, molar conductance, infrared spect...Three new complexes of N salicylidenamino acid with Zn? have been synthesized. The compositions and structures of the obtained complexes have been characterized by elemental analyses, molar conductance, infrared spectra, TG DTA and X ray powder diffraction. The three complexes have the compositions of Zn(sal β ala)·H2O(1),Zn(sal γ aba)·H2O(2),Zn(sal DL met)·1.5H2O(3)(sal=salicylidene,β ala=β alanine,γ aba=γ aminobutyric acid,DL met=DL methionine) and the molecular formula of ZnC10H11O4N, ZnC11H13O4N, ZnC12H16O4.5NS respectively. Infrared spectra of the complexes indicate that water has been coordinated. The thermal decomposition processes of the complexes show that the first weight losses are in good agreement with the water contents, and the compositions of the final residues are zinc oxide. The results of indexes to the X ray powder diffraction data indicate that the crystal structure of the three complexes belong to triclinic system. The lattice parameters are:a=1.9522nm,b=1.3904nm,c=2.0235nm,α=97.33°,β=98.66°,γ=99.05° for 1;a=1.3944nm,b=2.0880nm,c=2.4455nm,α=92.99°,β=95.48°,γ=96.18° for 2;a=2.1892nm,b=1.9171nm,c=1.4546nm,α=94.76°,β=95.09°,γ=94.12° for 3 respectively.展开更多
文摘Three new complexes of N salicylidenamino acid with Zn? have been synthesized. The compositions and structures of the obtained complexes have been characterized by elemental analyses, molar conductance, infrared spectra, TG DTA and X ray powder diffraction. The three complexes have the compositions of Zn(sal β ala)·H2O(1),Zn(sal γ aba)·H2O(2),Zn(sal DL met)·1.5H2O(3)(sal=salicylidene,β ala=β alanine,γ aba=γ aminobutyric acid,DL met=DL methionine) and the molecular formula of ZnC10H11O4N, ZnC11H13O4N, ZnC12H16O4.5NS respectively. Infrared spectra of the complexes indicate that water has been coordinated. The thermal decomposition processes of the complexes show that the first weight losses are in good agreement with the water contents, and the compositions of the final residues are zinc oxide. The results of indexes to the X ray powder diffraction data indicate that the crystal structure of the three complexes belong to triclinic system. The lattice parameters are:a=1.9522nm,b=1.3904nm,c=2.0235nm,α=97.33°,β=98.66°,γ=99.05° for 1;a=1.3944nm,b=2.0880nm,c=2.4455nm,α=92.99°,β=95.48°,γ=96.18° for 2;a=2.1892nm,b=1.9171nm,c=1.4546nm,α=94.76°,β=95.09°,γ=94.12° for 3 respectively.
