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Research on characteristics of embedded resonator sensor based on PtS2

Li Xin, Li Xieyuan, Zhang Haitao, Chen Shuang, Liu Shurong, Li Yang

Optica Applicata

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2023

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Vol. 53, nr 2

213--226

EN

An embedded microring resonator model using PtS2 as the core layer was designed and optimized for sensing. The inner layer is made of PtS2, and SiO2 and Si3N4 are used as cladding. The overall structure is Si3N4-SiO2-PtS2-SiO2-Si3N4. Field strength distribution of longitudinal section of single straight waveguide and the longitudinal section of coupling part of straight and annular waveguides are simulated according to the coupled-mode theory. The transfer matrix method is used to analyze characteristics between the length of the U-shaped feedback waveguide and the circumference of microring and the change of attenuation factor and coupling coefficient on the output spectrum. The simulation results showed that the embedded microring resonator with PtS2 as the core presents excellent optical properties. The resonance depth is more than –50 dB, and the sensitivity can reach 1806.61 dB/RIU. When the resonance wavelength is 1550.86 nm and the self-coupling coefficient is 0.9849. The corresponding detection limit is about 1.66056×10–7 dB/RIU, and the quality factor is 2.8848×10–5 under the measurement system with a signal-to-noise ratio of 30 dB. Compared with the traditional single microring structure, the proposed microring presents a higher free spectral range and more suitable for the fabrication of high-sensitivity, low-detection limit, and large-measurement range sensors.

2

A multi-model based adaptive reconfiguration control scheme for an electro-hydraulic position servo system

Zhang Zhao, Yang Zhong, Liu Shuchang, Chen Shuang, Zhang Xiaokai

International Journal of Applied Mathematics and Computer Science

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2022

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Vol. 32, no. 2

185--196

EN

Reliability and safety of an electro-hydraulic position servo system (EHPSS) can be greatly reduced for potential sensor and actuator faults. This paper proposes a novel reconfiguration control (RC) scheme that combines multi-model and adaptive control to compensate for the adverse effects. Such a design includes several fixed models, one adaptive model, and one reinitialized adaptive model. Each of the models has its own independent controller that is based on a complete parametrization of the corresponding fault. A proper switching mechanism is set up to select the most appropriate controller to control the current plant. The system output can track the reference model asymptotically using the proposed method. Simulation results validate robustness and effectiveness of the proposed scheme. The main contribution is a reconfiguration control method that can handle component faults and maintain the acceptable performance of the EHPSS.

3

A quantitative HPLC method for simultaneous determination of prodrug of voriconazole and voriconazole in beagle plasma, and its application to a toxicokinetic study

Wen Yufa, Chen Shuang, Yuan Yanjuan, Shao Qing, He Xuejun, Qiao Hongqun

Acta Chromatographica

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2022

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Vol. 34, no. 2

162--169

EN

A simple, rapid, efficient and reproducible method based on High Performance Liquid Chromatography (HPLC) for simultaneous determination of prodrug of voriconazole (POV) and voriconazole in beagle plasma has been established and validated. Omeprazole was utilized as the sole internal standard. Analytes and internal standards were extracted through protein precipitation and separated on a Venusil XBP C18 chromatography column (4.6 × 250 mm, 5 µm). The mobile phase was methanol and 20 mmol/L potassium dihydrogen phosphate. Chromatographic separation was achieved by using an isocratic elution procedure that used 65% methanol and a flow rate of 1 mL/min. The ultraviolet (UV) detection wavelength was 256 nm and the total running time was 15 min. This method showed good linear ranges of 100–75,000 ng/mL for voriconazole prodrug and 200–100,000 ng/mL for voriconazole respectively. The precision and accuracy were acceptable. Analytes in plasma samples are stable under different temperatures and storage conditions. The developed HPLC method has been successfully applied to the studies of toxicokinetics of POV after intravenous drip in beagle and provided important information for the further development and application.

4

Elevated-temperature tensile deformation and fracture behavior of particle-reinforced PM 8009Al matrix composite

Chen Shuang, Chen Guoqiang, Gao Pingping, Liu Chunxuan, Wu Anru, Dong Lijun, Huang Zhonghua, Ouyang Chun, Zhang Hui

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2021

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Vol. 69, nr 5

art. no. e138846

EN

Tensile tests of 8009Al alloy reinforced with SiC and Al₂O₃ particles fabricated by powder metallurgy (PM) were conducted at temperatures of 250–350°C and strain rates of 0.001–0.1 s⁻¹. The ultimate tensile strength and yield strength of the samples decreased while the temperature and strain rate increased. The elongation slightly decreased at first and then increased with growing temperature because of the medium-temperature brittleness of the alloy matrix. When the strain rate was 0.1 s⁻¹, the elongation of the 8009Al/Al₂O₃ composites always decreased with an increase in temperature because of the poorly coordinated deformation and weak bonding between the matrix and Al₂O₃ particles at such a high strain rate. The work-hardening rates of the composites sharply increased to maxima and then decreased rapidly as the strain increased. Meanwhile, the 8009Al/SiCₚ composites displayed superior UTS, YS, elongation, and work-hardening rates than those of the 8009Al/Al₂O₃ composites under the same conditions. Compared to 8009Al alloys reinforced with spherical Al₂O₃ particle, 8009Al alloys reinforced with irregular SiC particles exhibited a better strengthening effect. The fracture mechanism of the 8009Al/SiCₚ composites was mainly ductile, while that of the 8009Al/Al₂O₃ composites was primarily debonding at the matrix–particle interfaces in a brittle mode.