Yanshan University

About: Yanshan University is a education organization based out in Qinhuangdao, China. It is known for research contribution in the topics: Microstructure & Control theory. The organization has 19544 authors who have published 16904 publications receiving 184378 citations. The organization is also known as: Yānshān dàxué.

High Sensitivity of Refractive Index Sensor Based on Analyte-Filled Photonic Crystal Fiber With Surface Plasmon Resonance

Abstract: Two kinds of novel plasmonic high sensitivity of refractive index (RI) sensors based on analyte-filled photonic crystal fiber (AF-PCF) are proposed in this paper. The metallic gold and silver is used as the surface plasmon resonance activity metal. A full-vector finite-element method is applied to analyze and investigate the sensing and coupling characteristics of this designed AF-PCF with the gold or silver layer. Phase matching between the second surface plasmon polariton and fundamental modes can be met at different wavelengths as the analyte of the RI is increased from 1.40 to 1.42. The phase-matching wavelength of the designed AF-PCF with the gold layer is shifted to the longer wavelength direction compared with that with the silver layer, and the resonance strength is much stronger. The average sensitivities of 7040 and 7017 nm/RIU in the sensing are arranged from 1.40 to 1.42 with high linearity are achieved for the designed sensors with the gold and silver layers, respectively, which are almost the same. However, the figure of merit with the silver layer is much better than that with the gold layer.

Flexible Control Strategy for Grid-Connected Inverter Under Unbalanced Grid Faults Without PLL

Abstract: Power oscillation and current quality are the important performance targets for the grid-connected inverter under unbalanced grid faults. First, the inherent reason for the current harmonic and power oscillation of the inverter is discussed with a quantitative analysis. Second, a new control strategy is proposed to achieve the coordinate control of power and current quality without the need for a phase-locked loop (PLL) or voltage/current positive/negative sequence extraction calculation. Finally, the experimental tests are conducted under unbalanced grid faults, and the results verify the effectiveness of the propose method.

Wear resistance of Zr-based bulk metallic glass applied in bearing rollers

Abstract: Bearing rollers, 7.5 mm in diameter and 7.5 mm in length, were prepared from Zr 41 Ti 14 Cu 12.5 Ni 10 Be 22.5 bulk metallic glass (BMG). The working life of the bearing rollers was evaluated through a real rotation test with a large-load and at a high-speed, and compared with that of commercial GCr15 steel rollers. The results show that the bearing rollers of Zr-based bulk metallic glass have a better wear resistance than the commercial GCr15 ones. And the wear behaviors are different for these two kinds of bearing rollers.

Porphyrin-Based Carbon Dots for Photodynamic Therapy of Hepatoma.

Abstract: Porphyrin-containing carbon dots (CDs) possess ultrasmall size, excellent water solubility, and photostability. These CDs can effectively generate cytotoxic singlet oxygen upon irradiation, and induce the cell apoptosis. Photodynamic ability of CDs inhibits the growth of hepatoma. This work not only sheds light on developing functional carbon dots, but also highlights the importance of special-structure precursor molecules in synthesizing functional CDs.

First-principles study of electronic structure and optical properties of heterodiamond BC 2 N

Abstract: Heterodiamond ${\mathrm{BC}}_{2}\mathrm{N}$, as a kind of superhard material expectable, is studied using the ab initio pseudopotential density functional method. All the calculations are performed after geometric optimization starting from an eight-atom zinc-blende structure unit cell. For all the structures possible, we calculate in detail the structural parameters, charge transfers, bond populations, band structures, density of states, and optical properties (dielectric function, refractive index, absorption coefficient, reflectivity, electron energy loss spectrum, and photoconductivity). In addition, the optical anisotropy of some structures is also discussed. Our calculated results show that all the structures are metastable and some of them tend to form graphitelike structures and exhibit semimetallic behavior leading to interesting optical properties.