Publications by authors named "Yongchun Gao"

Three undescribed hybrid flavan-chalcones, caesalpinflavans D-F, and an unreported normonoterpene-chalcone heterodimer, caesalpinnone B, along with three known biflavonoids were isolated from the twigs and leaves of Caesalpinia digyna. Their structures were elucidated based on extensive spectroscopic analysis and quantum chemical calculations. Caesalpinflavan F was identified as a bis-(hybrid flavan-chalcone), its natural occurrence was supported by HPLC-IT-TOF-MS analysis.

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In recent years, topological semimetals/metals, including nodal point, nodal line, and nodal surface semimetals/metals, have been studied extensively because of their potential applications in spintronics and quantum computers. In this study, we predict a family of materials, ZrX (X = Al, Ga, In), hosting the nodal loop and nodal surface states in the absence of spin-orbit coupling. Remarkably, the energy variation of the nodal loop and nodal surface states in ZrX are very small, and these topological signatures lie very close to the Fermi level.

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Spin-gapless semiconductors (SGSs) with Dirac-like band crossings may exhibit massless fermions and dissipationless transport properties. In this study, by applying the density functional theory, novel multiple linear-type spin-gapless semiconducting band structures were found in a synthesized R 3 - c -type bulk PdF compound, which has potential applications in ultra-fast and ultra-low power spintronic devices. The effects of spin-orbit coupling and on-site Coulomb interaction were determined for the bulk material in this study.

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Hydrology and Water Resources Bureau of Guizhou Province, Guiyang 550002, China) Abstract: In order to explore the distribution characteristics of phytoplankton functional groups, eutrophication characteristics and response of phytoplankton functional groups to eutrophication in Xiaoguan Reservoir, phytoplankton and water samples were taken once a week from 25th July 2014 to 27th September 2014. The results showed that there were 22 phytoplankton functional groups, groups S1, D, J, B, G, MP, L₀, SN, X1, Y, Xph, F, T and W1 were comparatively common functional groups, Wherein, S1, D and J were the dominant functional groups. Weekly dynamics of phytoplankton functional groups were: S1-->S1-->S1-->S1-->S1--S1-->S1-->J/D/S1-->Sl1- >/1D.

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