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Anomalous quality factor evolution of induced transparency in a virtualized coupled-oscillator system

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 148-155页

作者： Yunhan Yang Han jia Tuo Liu Yuzhen Yang Jun Yang Key Laboratory of Noise and Vibration Research Institute of Acoustics Chinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences

The phenomenon of induced transparency, characterized by a high quality(Q) factor, holds significant importance in the fields of high-precision sensing, energy storage and wave manipulation. Conventional transparency systems are often constrained by the limited experimentally accessible parameter space and the lack of independent control over intrinsic parameters, thereby hindering advanced research on high-Q effects. Here we propose a virtualized coupled-oscillator system that enables reconfigurable induced transparency in the reflection spectrum. By virtually incorporating a pair of coupled oscillators into an individual acoustic meta-atom, we achieve the manipulation of induced transparency in a decoupled, wide-ranging, and elaborate manner. Exploiting the diverse evolutions across the intrinsic parameter space, we show experimentally a counter-intuitive increase in the Q-factor of the transparency window, which is attributed to the enhanced dissipation of the bright ***, a constant group delay at the center frequency is observed accompanying this evolution. Our work demonstrates an intriguing platform as well as a novel strategy to engineer high-Q induced transparency phenomenon, and paves the way towards applications in programmable acoustic sensors, filters and slow-wave devices.

关键词： induced transparency acoustic meta-atom high quality-factor scattering programmable intrinsic parameter

An Active Hybrid Electrocatalyst with Synergized Pyridinic Nitrogen-Cobalt and Oxygen Vacancies for Bifunctional Oxygen Reduction and Evolution

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Chinese Journal of Chemistry 2021年第3期39卷 655-660页

作者： wen-Xin zhong Xue-Ru Zhao jia-Yi Qin Jing Yang School of Materials Science and Engineering Institute of New Energy MaterialsTianjin UniversityTianjin 300072China

Main observation and conclusion A hybrid bifunctional oxygen reduction reaction(ORR)/oxygen evolution reaction(OER)NiCo_(2)O_(4-x)/NLG with rich pyridinic-nitrogen-cobalt coordination and oxygen vacancies was synthesized via a combination of the hydrothermal method and pulsed laser ***_(2)O_(4-x)/NLG exhibits an excellent catalytic activity with a low overpotential of 290 mV at 10 ***^(-2)for OER and a high half-wave potential of 0.85 V for *** a result,the overall ORR/OER overpotential ofNiCo_(2)O_(4-x)/NLG is only 0.67 V in 1.0 mol/L KOH electrolyte,which is superior to commercial noble-metal-based catalysts(Pt/C+RuO2).It is evidenced that the enhanced intrinsic OER and ORR activities of NiCo_(2)O_(4-x)/NLG are attributed to a synergistic effect between the pyridinic-N-Co coordination and the oxy-gen *** work provides a new design strategy for enhancing the intrinsic activity of bifunctional ORR/OER electrocatalysts.

关键词： Graphene Heterogeneous catalysis Electrochemistry Oxygen evolution reaction Oxygen reduction reaction

Simulation of Horizontal-Two-Dimension Focused Waves Using A Two-Layer Boussinesq-Type Model

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China Ocean Engineering 2023年第5期37卷 725-737页

作者： ZOU wen-feng WANG Ping LIU zhong-bo FANG Ke-zhao SUN jia-wen ZHANG Ning-chuan Key Laboratory of coastal and offshore engineering Dalian University of TechnologyDalian 116024China State Environmental Protection Key Laboratory of Marine Ecosystem Restoration National Marine Environmental Monitoring CenterDalian 116023China Dalian Maritime University College of Transportation EngineeringDalian 116024China

Accurate simulation of the horizontal-two-dimension(H2D)focused wave group in deep water requires high accuracy of a numerical *** two-layer Boussinesq-type model(Liu and Fang,2016;Liu et al.,2018)with the highest spatial derivative of 2 has high accuracy in both linear and nonlinear *** on the further development of the velocity equations(Liu et al.,2023),the H2D numerical model for water waves is established with the prediction-correction-iteration model in the finite difference method,and a composite fourth-order Adams-Bashforth-Moulton scheme is used for time *** wave generation method proposed by Hsiao et al.(2005)is applied and calibrated in this H2D *** numerical calculations lead to the following three main conclusions:First,compared with the analytical solution of Stokes linear waves,the calculated velocity profiles show higher accuracy by using the improved velocity ***,the simulations of the focused multidirectional wave group are carried out,and good agreements are found,demonstrating that the present H2D numerical model shows high accuracy in simulating focused multidirectional wave groups,and the effectiveness of the improved velocity formulas is also ***,the velocity profiles throughout the computational domain at the time of maximum wave crest are ***,the FFT method is used to obtain the amplitude with different frequencies for several locations,and the changes of the wavelet energy spectrum at different locations are presented for several cases.

关键词： focused wave horizontal-two-dimension model finite difference method nonlinear property

Synergistic promotion strategy of “dual-site” and “dual-path” to enhance the C–C coupling between CO2 and HCHO driven by photoelectrocatalysis

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Journal of Energy Chemistry 2025年第1期100卷 39-49页

作者： Hongqiang Yang jianfeng Zheng Guoyu Wang Yifei Gao Yatao Yang jia Li Xiaojin Han Yan Cui Zhanggen Huang National Key Laboratory of High Efficiency and Low Carbon Utilization of Coal Institute of Coal Chemistry Chinese Academy of Science University of Chinese Academy of Science Shenyang University of Chemical Technology

Photoelectrocatalytic coupling CO2and volatile organic compounds （VOCs） is a promising green strategy for the synergistic conversion of the two carbon-containing resources to *** catalytic efficiency is always at the mercy of chemical inertness of CO2and the competitive hydrogen evolution of ***,a modified g-C3N4/ZnAl-LDH Z-scheme heterojunction catalyst with dual reaction site was rationally designed and precisely *** Faraday efficiency of ethanol reached 68.67%with a corresponding formation rate of 227.3μmol *** revealed by in-situ characterizations and density functional theory calculations,CO2and HCHO were absorbed at Zn site and N site,***,*CO generated from CO2and HCHO was converted to*CH3O and*CHO on the dual-active-site *** detailed reaction mechanism experiments indicated that C–C coupling only occurred between*CO and*CH3O in electrocatalysis *** from the“*CO+*CH3O”path,another“*CO+*CHO”coupling path was also detected in photoelectrocatalytic *** selectivity of ethanol was significantly enhanced due to the synthesis of dual-site catalyst and the dual-path coupling path between CO2and HCHO simultaneously driven by light and electricity.

关键词： Photoelectrocatalysis Z-scheme C–C coupling Ethanol

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong Hou Shuo Zhang Jie Dang jia Guo Hanghang Zhou Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Particle-scale and sub-grid drag models coupled CFD for simulating the CO methanation in a CFB riser

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Particuology 2023年第12期83卷 178-193页

作者： jiageng Li Yong jia Bo Ouyang Bolun Yang Zheng-Hong Luo zhong-wen Liu Key Laboratory of Syngas Conversion of Shaanxi Province School of Chemistry&Chemical EngineeringShaanxi Normal UniversityXi'an710119China Department of Chemical Engineering School of Chemistry and Chemical EngineeringState Key Laboratory of Metal Matrix CompositesShanghai Jiao Tong UniversityShanghai200240China School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'an710049China

The diffusion and chemical reactions inside the catalyst particles and the heterogeneous flow structure in the computational cells are key factors to affect the accuracy of the coarse-grid simulation in circulating fluidized bed(CFB)methanation *** this work,a particle-scale model is developed to calculate the effective reaction rate considering the transient diffusion and chemical reactions in the particle scale,i.e.,the scale of the single catalyst particle.A modified sub-grid drag model is proposed to consider the effects of the meso-scale and chemical reactions on the heterogeneous gas-solid interaction,where the meso-scale is between the single particle and the whole reactor and featured with the particle ***,a coupled model is developed by integrating the particle-scale and modified sub-grid drag models into ***,the coupled model is validated to achieve accurate predictions on the CO methanation process in a CFB ***,the coupled model can be performed with a coarse grid(∼58 times particle diameter)and a large time step(0.005 s)to accelerate the *** simply changing the reaction kinetics,different gas-solid catalytic reaction systems can be simulated by using the coupled model.

关键词： Computational fluid dynamics Circulating fluidized bed co methanation Particle-scale model Drag model

Novel backstepping design for blended aero and reaction-jet missile autopilot

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Journal of Systems Engineering and Electronics 2008年第1期19卷 148-153页

作者： Liu zhong jia Xiaohong Opto-Electro Technology Development Center Luoyang 471009 P.R. China

The advanced missile uses blended control of nero-fin and reaction-jet to improve missile maneuverability. The blended control design, which is multi-inputs and multi-outputs （MIMO）, severe nonlinear, and model uncertain, is much more complex than conventional nero-fin control. A novel nonlinear backstepping control approach is proposed to design the blended autopilot. Missile model is reformed to a new one by state reconstruction technique so that it is easy to be handled by the backstepping method. Then a Lyapunov function is chosen to avoid oscillation caused in normal backstepping way when control parameters are mismatched. In distribution of both inputs, optimal energy logic is proposed. In addition, a fuzzy cerebellar model articulation controller （FCMAC） neural network is used to guarantee controller robustness to uncertainties. Finally, simulation results demonstrate the efficiency and advantages of the proposed method.

关键词： missile control blended aero-fin and reaction-jet control nonlinear backstepping optimal enery logic.

A non-uniform grid for triangular differential quadrature

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Science China(Physics,Mechanics & Astronomy) 2016年第12期59卷 52-59页

作者： HongZhi zhong jia Xu Department of Civil Engineering Tsinghua University

The triangular differential quadrature method based on a non-uniform grid is proposed in the paper. Explicit expressions of the non-uniform grid point coordinates are given and the weighting coefficients of the triangular differential quadrature method are determined with the aid of area coordinates. Two typical examples are presented to testify the effectiveness of the non-uniform grid. It is shown that rapid convergence is achieved under the non-uniform grid in comparison with those from the uniform grid with the same order of approximation.

关键词： differential quadrature triangular differential quadrature non-uniform grid weighting coefficient affine transformation

Effect of Pingan Fang, a Traditional Chinese Medicine compound, on behavioral sensitization and conditioned place preference induced by ethanol in mice

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Journal of Traditional Chinese Medicine 2016年第2期36卷 197-204页

作者： jia Lingyan Li Yibei Hu Xiaoyu Lin Wu wen Dachao zhong Sen Department of Clinical Medicine Chengdu University of Traditional Chinese Medicine Endocrinology Department Affiliated Hospital of Chengdu University of Traditional Chinese Medicine

OBJECTIVE:To observe the effect of Pingan Fang(PG)on behavioral sensitization and conditioned place preference(CPP)induced by ethanol in mice,and to determine the intervention mechanism of PG on alcohol ***:A behavioral sensitization mouse model induced by ethanol was established to observe the effect of PG on the development and expression of behavioral sensitization induced by ethanol by recording the spontaneous activity of *** resident time of mice in a white box was measured to evaluate the effect of PG on developing CPP induced by *** of dopamine(DA),Glutamate(Glu),and?-aminobutyric acid(GABA)in the corresponding mesolimbic region of mice were determined by enzyme-linked immunosorbent ***:Although PG did not alter spontaneous activity in mice,it reduced the growth of spontaneous activity stimulated by *** residence time in the white box after-ethanol-training of mice in CPP experiments was ***:Our data suggested that PG blocked the development and expression of behavioral sensitization induced by ethanol and the development of CPP in *** mechanism might be related to the decreased content of DA and Glu and increased content of GABA in the mesolimbic dopamine *** suggests that PG might be useful for the prevention and treatment of alcohol addiction.

关键词： Ethanol Pingan Fang Behavioral Sensi tization Conditioned place preference Dopamine Glutamic acid Aminobutyrates