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Science china(Information Sciences) 2025年第1期68卷 306-321页

作者： Cuijuan ZHANG Lianghao JI Shasha YANG Xing GUO Huaqing LI Chongqing key laboratory of Image Cognition Chongqing University of Posts and Telecommunications key laboratory of Intelligent Perception and Computing of Anhui Province Anqing Normal University College of electronic and Information Engineering Southwest University

This study uses event-triggered(ET) and reinforcement learning methods to investigate the optimal consensus control problem for cooperative-competitive multiagent systems. It proposes a novel distributed ET control strategy, which relies on a prioritized experience replay(PER) policy. This strategy not only conserves communication resources but also ensures acceptable system performance. To implement the proposed method, actor-critic(AC) dual-structured neural networks(NNs) are used to approximate the value function and control policy. In the AC NNs, the weight estimates for the NNs are updated at the moment of event triggering, resulting in a nonperiodic weight adjustment pattern. This approach decreases the computational cost in comparison with the traditional ET mechanism. The PER-based ET mechanism makes full use of valid historical data and effectively establishes a balance between system performance and communication resource ***, it does not require the following two conditions in most existing studies:(1) requirement of the system dynamics model to be known, and(2) persistent excitation. In addition, Zeno behavior is excluded from this study. Finally, a simulation is conducted to confirm the validity of the suggested approach.

关键词： multiagent systems event-triggered mechanism prioritized experience replay dual-structured neural networks optimal consensus control

The Radiative and Auger Decay Properties of K-Shell Ionized Np Ions

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Chinese Physics Letters 2012年第10期29卷 35-38页

作者： WANG Xiang-Li DONG Chen-Zhong XIE Lu-You SHI Ying-Long SABER Ismail Abdalla ZHOU Wei-Dong key laboratory of Atomic and Molecular Physics&Functional materials of Gansu Province College of Physics and Electronic EngineeringNorthwest Normal UniversityLanzhou 730070 key laboratory of electronic materials of the national affairs commission of china Northwest University for NationalitiesLanzhou 730030

The radiative and Auger decay processes of K-shell ionized Np ions are studied theoretically using the flexible atomic code(FAC).Relativistic effects,Breit interaction,QED corrections and nuclear finite mass and volume effects are considered *** resulting calculated K x-rays and Auger spectra of Np are compared with the measured spectra emitted after the electron-capture(EC)-decay of mass-separated ^(237)*** general consistency between theory and experiment is good;the relative intensities and relative positions of the peaks in the measured spectra are reproduced with good accuracy,in spite of the existence of different ways to produce the primary K-shell vacancy,enabling identification of the observed structure in the experimental *** find that most of the radiative transition rates are greater than the Auger transition rates,and the latter decrease rapidly with the transfer of initial vacancies to the outer shell.

关键词： radiative decay latter

Engineering of electronic and optical properties of ZnO thin films via Cu doping

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Chinese Physics B 2013年第4期22卷 491-494页

作者：张国恒邓小燕薛华向钢 key laboratory for electronic materials of the State national affairs commission of PRC School of Electrical Engineering Northwest University for Nationality Department of Physics and key laboratory for Radiation Physics and Technology of Ministry of Education Sichuan University

ZnO thin films doped with different Cu concentrations are fabricated by reactive magnetron sputtering technique. XRD analysis indicates that the crystal quality of the ZnO：Cu film can be enhanced by a moderate level of Cu-doping in the sputtering process. The results of XPS spectra of zinc, oxygen, and copper elements show that Cu-doping has an evident and complicated effect on the chemical state of oxygen, but little effect on those of zinc and copper. Interestingly, further investigation of the optical properties of ZnO：Cu samples shows that the transmittance spectra exhibit both red shift and blue shift with the increase of Cu doping, in contrast to the simple monotonic behavior of the Burstein–Moss effect. Analysis reveals that this is due to the competition between oxygen vacancies and intrinsic and surface states of oxygen in the sample. Our result may suggest an effective way of tuning the bandgap of ZnO samples.

关键词： ZnO thin films Cu doping optical properties bandgap tuning

Optomechanically induced transparency with Bose-Einstein condensate in double-cavity optomechanical system

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Chinese Physics B 2018年第3期27卷 274-279页

作者： Li-Wei Liu Duo-Jie Gengzang Xiu-Jia An Pei-Yu Wang College of Electrical Engineering Northwest University for NationalitiesLanzhou 730000China key laboratory for electronic materials of the State Ethnic affairs commission of PRC Northwest University for NationalitiesLanzhou 730000China

We propose a novel technique of generating multiple optomechanically induced transparency(OMIT)of a weak probe field in hybrid optomechanical *** system consists of a cigar-shaped Bose-Einstein condensate(BEC),trapped inside each high finesse Fabry-P6rot *** the resolved sideband regime,the analytic solutions of the absorption and the dispersion spectrum are *** tunneling strength of the two resonators and the coupling parameters of the each BEC in combination with the cavity field have the appearance of three distinct OMIT windows in the absorption ***,whether there is BEC in each cavity is a key factor in the number of OMIT windows *** technique presented may have potential applications in quantum engineering and quantum information networks.

关键词： optomechanically induced transparency Bose-Einstein condensate cavity optomechanical

Proton Irradiation Effects on the Structural and Tribological Properties of Polytetrafluoroethylene

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Chinese Journal of Polymer Science 2016年第12期34卷 1448-1455页

作者：刘百幸 Jun Liang Zhen-jun Peng Xiang-li Wang State key laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of Sciences key laboratory for electronic materials of the State Ethnic affairs commission College of Electric EngineeringNorthwest University for Nationalities

Polytetrafluoroethylene （PTFE） was irradiated with protons in a ground-based simulation facility to study the effects of proton irradiation on the structural and tribological properties of PTFE. The structural changes were characterized by X-ray photoelectron spectroscopy （XPS） and attenuated total-reflection FTIR （ATR-FTIR）, while the tribological properties were evaluated by friction and wear tests. It was found that proton irradiation induced the degradation of PTFE molecular chains, resulting in the increase of C concentration and the decrease in F concentration on the sample surfaces, and the surface chemical structure and morphology of the samples changed, which affected the friction coefficient and decreased the wear rate of the specimens as the friction and wear tests revealed.

关键词： Polytetrafluoroethylene Proton irradiation Degradation Friction and wear.

In-situ generation of Au-carbon-TiO_(2)Ohmic junction from Ti_(3)C_(2)MXene for efficient photocatalytic H_(2)evolution

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Journal of materials Science & Technology 2024年第21期188卷 144-154页

作者： Huanmin Liu Chao Wu Kangle Lv Dingguo Tang Qin Li key laboratory of Catalysis and Energy materials Chemistry of Ministry of Education&Hubei key laboratory of Catalysis and materials Science&key laboratory of Analytical Chemistry of the State Ethnic affairs commission South-Central Minzu UniversityWuhan 430074China

Photogenerated charge separation is a challenging step in semiconductor-based *** numerous efforts have been devoted to developing multi-component photocatalyst heterostructures for improving charge separation efficiency,the short distance between electrons and holes-aggregated regions still leads to undesirable charge ***,a facile and commercial in-situ synthesis method was designed to directly prepare a three-component Au–carbon–TiO_(2)photocatalyst from Ti_(3)C_(2)MXene,air,CO_(2),and HAuCl_(4),in which the carbon layer bridged Au and TiO_(2)nanoparticles for stable and efficient photocatalytic hydrogen *** probe measurements and density functional theory(DFT)calculations demonstrated that a multi-interfacial charge transmission network was successfully constructed to achieve a directional and long-distance spatial charge separation/transfer channel between TiO_(2)and Au through carbon layer,desirably inhibiting the recombination of photogenerated charge *** hydrogen production rate of the formed three-component Au/C–TiO_(2)(CTA)photocatalyst was demonstrated to be 27 times higher than that of Au–TiO_(2),which also surpassed many reported Ti_(3)C_(2)MXene-derived carbon–TiO_(2)*** work sheds light on the ingenious use of 2D MXene to form a well-behaved TiO_(2)-based photocatalytic system and helps to propose future design principles in accelerating charge transfer.

关键词： Photocatalytic hydrogen production Ti_(3)C_(2) MXene Carbon layer TiO_(2) Ohmic junction

Electrospun Semiconductor-Based Nano-Heterostructures for Photocatalytic Energy Conversion and Environmental Remediation:Opportunities and Challenges

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Energy & Environmental materials 2023年第2期6卷 212-238页

作者： Na Lu Mingyi Zhang Xuedong Jing Peng Zhang Yongan Zhu Zhenyi Zhang key laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic affairs commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian 116600China key laboratory for Photonic and electronic Bandgap materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of materials Science and Engineering Zhengzhou UniversityZhengzhou 45001China

Harvesting solar energy to drive the semiconductor photocatalysis offers a promising tactic to address ever-growing challenges of both energy shortage and environmental *** and synthesis of nano-heterostructure photocatalysts with controllable components and morphologies are the key factors for achieving highly efficient photocatalytic ***(1D)semiconductor nanofibers produced by electrospinning possess a large ratio of length to diameter,high ratio of surface to volume,small grain sizes,and high porosity,which are ideally suited for photocatalytic reactions from the viewpoint of structure *** the secondary treatment of these nanofibers through the solvothermal,gas reduction,in situ doping,or assembly methods,the multi-component nanofibers with hierarchical nano-heterostructures can be obtained to further enhance their light absorption and charge carrier separation during the photocatalytic *** recent years,the electrospun semiconductorbased nano-heterostructures have become a“hot topic”in the fields of photocatalytic energy conversion and environmental *** review article summarizes the recent progress in electrospinning synthesis of various kinds of high-performance semiconductor-based nano-heterostructure photocatalysts for H2 production,CO_(2) reduction,and decomposition of *** future perspectives of these materials are also discussed.

关键词： electrospun nanofibers energy conversion environmental remediation photocatalysis semiconductor heterojunction

Effective ethanol-to-CO_(2) electrocatalysis at iridium-bismuth oxide featuring the impressive negative shifting of the working potential

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Journal of Energy Chemistry 2023年第11期86卷 23-31,I0002页

作者： Ruilin Wei Yue Liu Huazhong Ma Xingyu Ma Yaoyue Yang key laboratory of General Chemistry of the national Ethnic affairs commission School of Chemistry and EnvironmentSouthwest Minzu UniversityChengdu 610041SichuanChina

Since low overpotential for the anodic ethanol oxidation reaction(EOR)can favor the higher output voltage and power of direct ethanol fuel cells(DEFCs),it is critical to design new EOR catalysts with efficient ethanol-to-CO_(2)activity at low applied ***,carbon-supported Ir-Bi_(2)O_(3)(Ir-Bi_(2)O_(3)/C)catalysts with highly dispersive bismuth oxide on the iridium surface are designed and prepared,which can merit splitting the ethanol C–C bond and promoting the oxidation of C1 intermediates at the bifunctional *** as-obtained Ir-Bi2O3/C catalysts show superior EOR mass activity of up to ca.2250 m A ***,they exhibit the record lowest onset oxidation potentials(0.17–0.22 V ***)and the peak potential(ca.0.58 V ***),being 130–300 m V lower than the previous landmark noble metallic ***,an apparent C1 pathway faraday efficiency(FEC1)of 28%±5.9%at 0.5 V *** can be obtained at Ir-Bi_(2)O_(3)/*** work might provide new insights into the new anodic EOR catalysts for increasing the power of DEFCs.

关键词： EOR Low overpotential C1 selectivity Iridium Bismuth oxide

COVID-19 Interpretable Diagnosis Algorithm Based on a Small Number of Chest X-Ray Samples

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Journal of Shanghai Jiaotong university(Science) 2022年第1期27卷 81-89页

作者： BU Ran XIANG Wei CAO Shitong key laboratory of electronic and Information Engineering State Ethnic Affairs Commission(Southwest Minzu University)Chengdu 610041China

The COVID-19 medical diagnosis method based on individual’s chest X-ray(CXR)is achieved difficultly in the initial research,owing to difficulties in identifying CXR data of COVID-19 *** the beginning of the study,infected individuals’CXRs were *** combination of artificial intelligence(AI)and medical diagnosis has been advanced and *** solve the difficulties,the interpretability analysis of AI model was used to explore the pathological characteristics of CXR samples infected with COVID-19 and assist in medical *** dataset was expanded by data augmentation to avoid *** learning was used to test different pre-trained models and the unique output layers were designed to complete the model training with few *** this study,the output results of four pre-trained models in three different output layers were compared,and the results after data augmentation were compared with the results of the original *** control variable method was used to conduct independent tests of 24 ***,99.23% accuracy and 98% recall rate were obtained,and the visual results of CXR interpretability analysis were *** network of COVID-19 interpretable diagnosis algorithm has the characteristics of high generalization and *** can be quickly applied to other urgent tasks with insufficient experimental *** the same time,interpretability analysis brings new possibilities for medical diagnosis.

关键词： COVID-19 chest X-ray(CXR) interpretability data augmentation transfer learning convolutional neural network

A DFT study on Pt single atom loaded COF for efficient photocatalytic CO_(2)reduction

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Journal of materials Science & Technology 2024年第3期170卷 87-94页

作者： Fei Xie Chuanbiao Bie Jian Sun Zhenyi Zhang Bicheng Zhu laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430078China key laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic affairs commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian116600China

Photocatalytic CO_(2)reduction provides a promising strategy for the alleviation of greenhouse effect and energy shortage *** single atom modification is an effective method to improve the CO_(2)reduction performance of covalent organic framework(COF)photocatalysts,while the intrinsic mechanism is not revealed in ***,a Pt-COF photocatalytic system was constructed by embedding Pt single atom in TFPT-TMT-COF(TFPT:1,3,5-tris(4-formylphenyl)-triazine,TMT:2,4,6-trimethyl-1,3,5-triazine).Based on density functional theory(DFT)calculation,the geometric structure and electronic property of Pt-COF were investigated,and the CO_(2)adsorption and reduction reaction process on Pt-COF were *** results show that the Pt atom can be steadily anchored in COF via the formation of Pt-N and Pt-C ***,there is strong electronic interaction between Pt and *** incorporation of Pt atom benefits the CO_(2)reduction activity of COF from multiple aspects:(ⅰ)reducing the band gap and improving light absorption;(ⅱ)enhancing CO_(2)adsorption and activating the CO_(2)molecule;(ⅲ)decreasing the energy barrier in the hydrogenation step of CO_(2)→COOH,thus facilitating CO_(2)conversion to CO;(ⅳ)inhibiting the hydrogenation of CO,thereby increasing the selectivity of *** work brings a novel insight into the excellent CO_(2)reduction performance of Pt modified COF,and provides useful references for the design of single atom photocatalysts.

关键词： Photocatalysis Carbon dioxide reduction Covalent organic framework Pt single atom Theoretical calculation