Complete active space multiconfiguration self-consisten-field (CAS-MCSCF)calculations are carried out on the ground stae() of W_2. The spectroscopic properties(Re=2.078A. De=4.224eV and ωe=304.3cm-1) and the poential...Complete active space multiconfiguration self-consisten-field (CAS-MCSCF)calculations are carried out on the ground stae() of W_2. The spectroscopic properties(Re=2.078A. De=4.224eV and ωe=304.3cm-1) and the poential energy curve of the state are reported. The calculations predict the W-W bond order of 5.02.展开更多
One-component, catalyst-free self-healing coatings with double-shelled polymer microcapsules have drawn considerable attention due to wide applications. In this work, the synthesis parameters of double-shelled polymer...One-component, catalyst-free self-healing coatings with double-shelled polymer microcapsules have drawn considerable attention due to wide applications. In this work, the synthesis parameters of double-shelled polymer microcapsules and the mechanism of the self-healing process were systematically investigated. Apart from the chemical structure of the microcapsule shell, the shell thickness, the microcapsule size,and the core fraction could affect the self-healing anticorrosion properties. The synthesis parameters were further optimized in terms of the agitation rate, p H, weight ratio of core to shell, and temperature. Under these conditions, the microcapsule shell consisting of a rough surface formed by poly(urea-formaldehyde) and a smooth inner wall by polyurethane was prepared. The size of the microcapsules and core fraction were calculated to be approximately 30 μm and 75%, respectively. The self-healing anticorrosion coating incorporating as-synthesized microcapsules exhibited corrosion resistance in artificially scratched areas, which was further characterized by electrochemical impedance spectroscopy.展开更多
文摘Complete active space multiconfiguration self-consisten-field (CAS-MCSCF)calculations are carried out on the ground stae() of W_2. The spectroscopic properties(Re=2.078A. De=4.224eV and ωe=304.3cm-1) and the poential energy curve of the state are reported. The calculations predict the W-W bond order of 5.02.
基金financially supported by the National Key Research and Development Plan (No. 2016YFC0303700)the National Natural Science Foundation of China (No. 51803215)+1 种基金CAS Pioneer Hundred Talents ProgramBeijing Municipal Natural Science Foundation (No. 2182075)
文摘One-component, catalyst-free self-healing coatings with double-shelled polymer microcapsules have drawn considerable attention due to wide applications. In this work, the synthesis parameters of double-shelled polymer microcapsules and the mechanism of the self-healing process were systematically investigated. Apart from the chemical structure of the microcapsule shell, the shell thickness, the microcapsule size,and the core fraction could affect the self-healing anticorrosion properties. The synthesis parameters were further optimized in terms of the agitation rate, p H, weight ratio of core to shell, and temperature. Under these conditions, the microcapsule shell consisting of a rough surface formed by poly(urea-formaldehyde) and a smooth inner wall by polyurethane was prepared. The size of the microcapsules and core fraction were calculated to be approximately 30 μm and 75%, respectively. The self-healing anticorrosion coating incorporating as-synthesized microcapsules exhibited corrosion resistance in artificially scratched areas, which was further characterized by electrochemical impedance spectroscopy.