偕胺肟基对铀酰离子具有很强的络合能力及较高的选择性,目前已成为海水提铀吸附材料研究的热点.本文运用阿姆斯特丹密度泛函(Amsterdam density functional,简称ADF)方法研究了UO_2^(2+)、Fe^(3+)、Ni^(2+)、Co^(2+)与不同取代基(—OH,...偕胺肟基对铀酰离子具有很强的络合能力及较高的选择性,目前已成为海水提铀吸附材料研究的热点.本文运用阿姆斯特丹密度泛函(Amsterdam density functional,简称ADF)方法研究了UO_2^(2+)、Fe^(3+)、Ni^(2+)、Co^(2+)与不同取代基(—OH,—NH_2,—H,—F,—CF_3)偕胺肟的络合反应.密度泛函理论(density functional theory,简称DFT)对这些配位化合物的几何结构进行优化和相关热力学参数的计算与收集.从键能强弱方面分析,不同取代基偕胺肟螯合的基本趋势都是Fe^(3+)最稳定的,而UO_2^(2+)螯合是最不稳定的.从热力学角度分析,表明偕胺肟最容易与UO_2^(2+)和Co^(2+)进行螯合,而取代基为—CF_3的偕胺肟最难与UO_2^(2+)和Co^(2+)进行螯合.在液相环境中不同取代基偕胺肟与UO_2^(2+)和Co^(2+)离子螯合的稳定顺序均为—NH_2>—OH>—H>—F>—CF_3.在η2构型中,偕胺肟比其他取代基偕胺肟更稳定,其中UO2+2与氨基偕胺肟螯合过程中的ΔG(吉布斯自由能变)最低为-646.65 k J/mol.展开更多
Helium effects on dislocation and cavity formation of Fe-11 wt.% Cr model alloy are investigated. Single-beam(electron) and dual-beam(He^+/e^-) irradiations are performed at 350℃ and 400℃ using an ultra-high voltage...Helium effects on dislocation and cavity formation of Fe-11 wt.% Cr model alloy are investigated. Single-beam(electron) and dual-beam(He^+/e^-) irradiations are performed at 350℃ and 400℃ using an ultra-high voltage electron microscope combined with ion accelerators. In-situ observation shows that the growth rate of dislocation loops is reduced in the helium pre-injected specimen. The mean size of cavities decreased in the helium preinjected specimen. The possible mechanisms are discussed.展开更多
文摘偕胺肟基对铀酰离子具有很强的络合能力及较高的选择性,目前已成为海水提铀吸附材料研究的热点.本文运用阿姆斯特丹密度泛函(Amsterdam density functional,简称ADF)方法研究了UO_2^(2+)、Fe^(3+)、Ni^(2+)、Co^(2+)与不同取代基(—OH,—NH_2,—H,—F,—CF_3)偕胺肟的络合反应.密度泛函理论(density functional theory,简称DFT)对这些配位化合物的几何结构进行优化和相关热力学参数的计算与收集.从键能强弱方面分析,不同取代基偕胺肟螯合的基本趋势都是Fe^(3+)最稳定的,而UO_2^(2+)螯合是最不稳定的.从热力学角度分析,表明偕胺肟最容易与UO_2^(2+)和Co^(2+)进行螯合,而取代基为—CF_3的偕胺肟最难与UO_2^(2+)和Co^(2+)进行螯合.在液相环境中不同取代基偕胺肟与UO_2^(2+)和Co^(2+)离子螯合的稳定顺序均为—NH_2>—OH>—H>—F>—CF_3.在η2构型中,偕胺肟比其他取代基偕胺肟更稳定,其中UO2+2与氨基偕胺肟螯合过程中的ΔG(吉布斯自由能变)最低为-646.65 k J/mol.
基金the National Natural Science Foundation of China under Grant Nos U1832133,11475229 and 91426301
文摘Helium effects on dislocation and cavity formation of Fe-11 wt.% Cr model alloy are investigated. Single-beam(electron) and dual-beam(He^+/e^-) irradiations are performed at 350℃ and 400℃ using an ultra-high voltage electron microscope combined with ion accelerators. In-situ observation shows that the growth rate of dislocation loops is reduced in the helium pre-injected specimen. The mean size of cavities decreased in the helium preinjected specimen. The possible mechanisms are discussed.
