Publications by authors named "Bao Jia Yang"

Fourteen sesquiterpene lactones were isolated from the whole plant of L. Their structures were determined on the basis of comprehensive spectroscopic data analysis. All compounds were screened for their cytotoxic activity, and compound showed the strongest activity (IC 2.

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Ten new nortriterpenes, euphorbiumrins A-J (1-10), together with three known analogues (11-13) were isolated from the latex of Euphorbia resinifera. Their structures were established on the basis of extensive spectroscopic analyses (IR, UV, HRESIMS, 1D and 2D NMR). Their inhibitions on tomato yellow leaf curl virus (TYLCV) were evaluated and compound 5 exhibited significant anti-TYLCV activity with an inhibition rate of 71.

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Two new C21 steroidal glycosides, paniculatumosides H and I, together with four known ones were isolated from the roots of Cynanchum paniculatum (Bge.) Kitag. Their structures were identified by spectroscopic methods including extensive 1D and 2D NMR techniques.

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We numerically demonstrate that spoof localized surface plasmons (LSPs) resonant modes can be enhanced based on ultrathin corrugated metal-insulator-metal (MIM) ring resonator. Further enhancement of the LSPs modes has been achieved by incorporating an efficient and ease-of-integration exciting method. Quality factors of resonance peaks have become much larger and multipolar resonances modes can be easily observed on the textured MIM ring resonator excited by a microstrip line.

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We have investigated the fundamental and high-order spoof localized surface plasmons (LSPs) modes in the proposed corrugated ring resonator printed on a thin dielectric substrate with or without ground plane. An efficient and ease-of-integration method to excite spoof LSPs in the textured ring resonator has been adopted to suppress unwanted high-order modes and enhance fundamental modes. A multi-band-pass filter has been proposed and numerically demonstrated.

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Although subwavelength planar terahertz (THz) plasmonic devices can be implemented based on planar spoof surface plasmons (SPs), they still suffer from a little high propagation loss. Here the dispersion and propagation characteristics of the spoof plasmonic waveguide composed of double metal strips corrugated with dumbbell shaped grooves have been investigated. It has been found that much lower propagation loss and longer propagation length can be achieved based on the waveguide compared with the conventional spoof plasmonic waveguide with rectangular grooves.

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We propose a broadband slow wave system based on the thin metal-insulator-metal (MIM) graded grating structure composed of two corrugated metal strips with periodic array of grooves on a thin dielectric substrate. The guided spoof surface plasmon polaritons (SSPPs) at different frequencies can be localized at different positions along the ultrathin MIM grating. By introducing specially designed non-corrugated MIM branches with specific lengths at the locations where the EM waves are trapped, the trapped EM waves can be released and propagate along these branches.

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