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Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： Da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng college of materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

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Synthesis of Branched Chains with Actuation Redundancy for Eliminating Interior Singularities of 3T1R Parallel Mechanisms

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Chinese Journal of Mechanical Engineering 2016年第2期29卷 250-259页

作者： LI Shihua LIU Yanmin CUI Hongliu NIU Yunzhan ZHAO Yanzhi hebei Provincial Key Laboratory of Parallel Robot and Mechatronic System Yanshan University Qinhuangdao 066004 China hebei vocationa & technical college of building materials Qinhuangdao 066004 China

Although it is common to eliminate the singularity of parallel mechanism by adding the branched chain with actuation redundancy, there is no theory and method for the configuration synthesis of the branched chain with actuation redundancy in parallel mechanism. Branched chains with actuation redundancy are synthesized for eliminating interior singularity of 3-translational and 1-rotational（3T1R） parallel mechanisms. Guided by the discriminance method of hybrid screw group according to Grassmann line geometry, all the possibilities are listed for the occurrence of interior singularities in 3T1R parallel mechanism. Based on the linear relevance of screw system and the principles of eliminating parallel mechanism singularity with actuation redundancy, different types of branched chains with actuation redundancy are synthesized systematically to indicate the layout and the number of the branched chainsinterior with actuation redundancy. A general method is proposed for the configuration synthesis of the branched chains with actuation redundancy of the redundant parallel mechanism, and it builds a solid foundation for the subsequent performance optimization of the redundant actuation parallel mechanism.

关键词： parallel mechanism interior singularity hybrid screw group branched chain with actuation redundancy

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Numerical Simulation and Experimental Study of Heat-fluid-solid Coupling of Double Flapper-nozzle Servo Valve

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 1030-1038页

作者： ZHAO Jianhua ZHOU Songlin LU Xianghui GAO Dianrong hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University hebei vocational & technical college of building materials

The double flapper-nozzle servo valve is widely used to launch and guide the equipment. Due to the large instantaneous flow rate of servo valve working under specific operating conditions, the temperature of servo valve would reach 120℃ and the valve core and valve sleeve deform in a short amount of time. So the control precision of servo valve significantly decreases and the clamping stagnation phenomenon of valve core appears. In order to solve the problem of degraded control accuracy and clamping stagnation of servo valve under large temperature difference circumstance, the numerical simulation of heat-fluid-solid coupling by using finite element method is done. The simulation result shows that zero position leakage of servo valve is basically impacted by oil temperature and change of fit clearance. The clamping stagnation is caused by warpage-deformation and fit clearance reduction of the valve core and valve sleeve. The distribution roles of the temperature and thermal-deformation of shell, valve core and valve sleeve and the pressure, velocity and temperature field of flow channel are also analyzed. Zero position leakage and electromagnet＇s current when valve core moves in full-stroke are tested using Electro-hydraulic Servo-valve Characteristic Test-bed of an aerospace sciences and technology corporation. The experimental results show that the change law of experimental current at different oil temperatures is roughly identical to simulation current. The current curve of the electromagnet is smooth when oil temperature is below 80℃, but the amplitude of current significantly increases and the hairy appears when oil temperature is above 80℃. The current becomes smooth again after the warped valve core and valve sleeve are reground. It indicates that clamping stagnation is caused by warpage-deformation and fit clearance reduction of valve core and valve sleeve. This paper simulates and tests the heat-fluid-solid coupling of double flapper-nozzle servo valve, an

关键词： double flapper-nozzle servo valve heat-fluid-solid coupling numerical simulation warpage-deformation clamping stagnation zero position leakage

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Bifunctional bridging capping layer enables 24.5% efficiency of perovskite solar cells with polymer-based hole transport materials

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Science China Chemistry 2025年第1期 350-359页

作者： Can Zhu Yiyang Wang Lei Meng Beibei Qiu Jing Li Shucheng Qin Ke Hu Xin Jiang Wenbin Lai Minchao Liu Zhe Liu Chenxing Lu Jinyuan Zhang Yongfang Li Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic Solids Institute of Chemistry Chinese Academy of Sciences School of Chemical Science University of Chinese Academy of Sciences Key Laboratory of Solid State Optoelectronic Devices of Zhejiang Province College of Physics and Electronic Information Engineering Zhejiang Normal University Key Laboratory of Photochemical Conversion and Optoelectronic materials Technical Institute of Physics and ChemistryChinese Academy of Sciences Laboratory of Advanced Optoelectronic materials College of Chemistry Chemical Engineering and Materials ScienceSoochow University

Developing a bridge capping layer between perovskite and hole transport layer materials（HTMs） in the n-i-p perovskite solar cells（pero-SCs） is an effective approach to modify the morphology of HTMs and passivate the perovskite ***, we select the quinoxaline-based bifunctional passivation agent, quinoxalin-6-yl-methylamine hydrochloride（Qx MACl）,as the bridging layer, and a D-A copolymer PBQ12 containing the same quinoxaline unit as an HTM for the n-i-p pero-SCs. Due to the π-π stacking among the common quinoxaline units in the bridge layer and HTM, Qx MACl induces the π-π stacking of the PBQ12 film and improves the film morphology of HTMs with better conductivity. Additionally, Qx MACl can effectively passivate the perovskite surface, and PBQ12 possesses appropriate energy levels and high hole mobility. The pero-SCs based on FAPbI3with PBQ12/Qx MACl treatment showed a higher power conversion efficiency（PCE） of 24.05% and outstanding stability, maintaining 95.4% and 92.1% of its initial PCE after 750 h of storage and after over 800 h of thermal annealing at 85 °C, respectively. To further enhance the PCE of the PBQ12/Qx MACl-based devices, we developed a non-metal ion dopant for the PBQ12 HTM. Through trace doping of PBQ12 HTM by the non-metal ion dopant, the PCE of the PBQ12/Qx MACl-based devices reached 25.24%（the calibrated PCE of 24.55% by the National Institute of Metrology, China）.

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Preparation of high-performance ultrafine-grained AISI 304L stainless steel under high temperature and pressure

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Progress in Natural Science:materials International 2016年第4期26卷 404-410页

作者： Peng Wang Jinzan Zhang Yang Zhang Haitao Wang Wentao Hu Dongli Yu State Key Laboratory of Metastable materials Science and Technology Yanshan University hebei vocational and technical college of building materials China Energy Research Society

Bulk ultra-fine grained(UFG) AISI 304 L stainless steel with excellent mechanical properties was prepared by a high-temperature and high-pressure(HTHP) method using nanocrystalline AISI 304 L stainless steel powders obtained from ball milling. Samples were sintered in high-pressure conditions using the highest martensite content of AISI 304 L stainless steel powders milled for 25 h. Analyses of phase composition and grain size were accomplished by X-ray diffraction and Rietveld refinement. By comparing the reverse martensite transformation under vacuum and HTHP treat, we consider that pressure can effectively promote the change in the process of transformation. Compared with the solid-solution-treated 304 L,the hardness and yield strength of the samples sintered under HTHP are considerably higher. This method of preparation of UFG bulk stainless steel may be widely popularised and used to obtain UFG metallic materials with good comprehensive performance.

关键词： AISI 304L stainless steel Ultra-fine grained bulk Ball milling High temperature high pressure Mechanical properties

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Wireless Channel Measurements and Modeling of LTE Broadband System for High-Speed Railway Scenarios

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Chinese Journal of Electronics 2018年第5期27卷 1092-1097页

作者： ZHAO Hua LYU Qing LIU Yachuan CHEN Jiaxing ZHANG Shujing hebei Normal University Career Technical College

In high-speed scenarios, channel model is of vital importance in Long term evolution(LTE) *** extensive measurements on Beijing-Tianjin railway, this paper proposes a distance-dependent channel model. Both large-scale and small-scale channel characteristics are presented in detail. The large-scale path loss is modeled under the hierarchical network structure. Small-scale channel characteristics that include channel impulse response,power delay profile and Doppler spectrum are deduced and analyzed. In particular, a new stage-wise K-factor model is proposed. Combined with the cumulative distribution function of Root-mean squared(RMS) delay spread and the number of paths, they clearly illustrate the distancedependent variances of the channel. Finally, the integrated distance-dependent channel models are proposed to give a comprehensive description of broadband LTE channel in high-speed railway scenario.

关键词： Distance-dependent channel model High-speed railway LTE system K-factor Delay spread

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Biomass materials for zinc-based sustainable and green energy storage devices:Strategy and mechanism

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Nano Research 2025年第1期18卷 294-314页

作者： Xiaotong Yang Xiaoxin Nie Chenke Tang Yiyang Xiao Qiongguang Li Du Yuan Meng Yao college of materials Science and Engineering Changsha University of Science and TechnologyChangsha 410004China college of materials Science and Engineering Sichuan UniversityChengdu 610065China Anhui Province International Research Center on Advanced building materials School of Materials and Chemical EngineeringAnhui Jianzhu UniversityHefei 230601China

As next-generation rechargeable alternatives,zincbased energy storage devices(ZESs)are being intensely explored due to their merits of abundant resource,low cost,safety and environmental ***,ZESs face a succession of critical challenges on pursuing advancing performance,including the stability and kinetics of cathode,stability and transport of zinc electrolyte,reversibility and deep utilization of metallic Zn ***,possessing unique molecular structures with abundant functionals groups,motivates the interdisciplinary field emerging from biomass and aqueous rechargeable *** its high compatibility with ZES design,we here summarize the application of biomass materials in ZESs from the aspects of cathode,electrolyte,membrane/separator and Zn anode,with their corresponding operational mechanisms and attractive functionalities from polymeric ***,the outlooks and perspectives are provided,regarding current challenges and future *** anticipate our minireview paves way on exploring the roles of biomass in aqueous rechargeable batteries.

关键词： zinc biomass materials skeleton/host coating solid-electrolyte interphase(SEI)

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Acoustic Response and Micro-Damage Mechanism of Fiber Composite materials under Mode-Ⅱ Delamination

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Chinese Physics Letters 2015年第4期32卷 73-76页

作者：周伟吕智慧王雅瑞刘然陈维业李晓彤 college of Quality and technical Supervision Hebei University

Realizing the accurate characterization for the dynamic damage process is a great challenge. Here we carry out testing simultaneously for dynamic monitoring and acoustic emission （AE） statistical analysis towards fiber composites under mode-Ⅱ delamination damage. The load curve, AE relative energy, amplitude distribution, and amplitude spectrum are obtained and the delamination damage mechanism of the composites is investigated by the microscopic observation of a fractured specimen. The results show that the micro-damage accumulation around the crack tip region has a great effect on the evolutionary process of delamination. AE characteristics and amplitude spectrum represent the damage and the physical mechanism originating from the hierarchical microstructure. Our finding provides a novel aud feasible strategy to simultaneously evaluate the dynamic response and micro-damage mechanism for fiber composites.

关键词： der Delamination Acoustic Response and Micro-Damage Mechanism of Fiber Composite materials under Mode

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology college of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic materials & CAS-HKU Joint Laboratory on New materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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Application research of radio communication in mine alarm system

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Journal of Coal Science & Engineering(China) 2006年第1期12卷 110-114页

作者：刘士光沈春宝李艳萍王庆祝乔小辉 Department of Mechanical and Electrical Hebei Normal University of Science & Technology Qinhuangdao 066004 China Department of Mechinery and Electronics Hebei Vocational & Technical College of Building Materials Qinhuangdao 066004 China

In this paper, the configuration characteristic of the safe parameter measurement and alarm system in new type mine was first simply introduced, which is made up of topological structure and combines wire communication with radio communication, then introduced respectively the hardware and software construction and the working principle and the method of design, which is composed of detecting instrument as the core of enhanced single chip microcomputer AT89S8252 and relay station and CPU which consists of IPC. The three class computer communication system that integrates with measurement and alarm and management works reliably and uses conveniently, especially to thesystem of parameter detecting and alarm in mine, which is adapted to measure dispersedly and manage intensively.

关键词： mine measurement industrial personal computer single chip microcomputer data communication

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