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Nano-Micro Letters 2024年第10期16卷 47-81页

作者： Dujuan Li Yuxuan guo Chenxing zhang Xianhe Chen Weisheng zhang Shilin Mei Chang-Jiang Yao State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081People's Republic of China

Aqueous zinc-ion batteries(AZIBs)are one of the most compelling alternatives of lithium-ion batteries due to their inherent safety and economics *** response to the growing demand for green and sustainable energy storage solutions,organic electrodes with the scalability from inexpensive starting materials and potential for biodegradation after use have become a prominent choice for *** gratifying progresses of organic molecules with electrochemical performance in AZIBs,the research is still in infancy and hampered by certain issues due to the underlying complex *** for designing organic electrode materials for AZIBs with high specific capacity and long cycling life are discussed in detail in this ***,we put emphasis on the unique electrochemistry of different redox-active structures to provide in-depth understanding of their working *** addition,we highlight the importance of molecular size/dimension regarding their profound impact on electrochemical ***,challenges and perspectives are discussed from the developing point of view for future *** hope to provide a valuable evaluation on organic electrode materials for AZIBs in our context and give inspiration for the rational design of high-performance AZIBs.

关键词： Aqueous zinc-ion batteries Organic electrodes Functional groups Molecular size/geometry Electrochemical performances

Tendencies of alloyed engineering in BiOX-based photocatalysts:a state-of-the-art review

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Rare Metals 2024年第4期43卷 1488-1512页

作者： Yan-Dong Sun Chao Zeng Xue zhang Zi-Qi zhang Bo Yang Sheng-Qi {2. Tianjin Key Laboratory of Clean Energy and Pollutant Control School of Energy and Environmental EngineeringHebei University of TechnologyTianjin300401China State-Province Joint Engineering Laboratory of Zeolite Membrane Materials Institute of Advanced MaterialsCollege of Chemistry and Chemical EngineeringJiangxi Normal UniversityNanchang330022China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation School of Physics and Electronic InformationAnhui Province Industrial Generic Technology Research Center for Alumics MaterialsHuaibei Normal UniversityHuaibei235000China

Energy-saving and environmentally friendly photocatalysis has emerged as a popular research area in response to issues with energy scarcity and environmental *** to the unique layer-like structure,BiOX(Cl,Br,I)is frequently used in ***,inherent flaws in BiOX,such as an inappropriate band gap and low carrier separation efficiency,restrict its capacity for *** to the tunable grouping layer,alloying engineering is employed to optimize the intrinsic properties of BiOX and alloyed BiOX becomes a promising photocatalytic *** review describes the structure of BiOX,where tunable halogen layers provide favorable conditions for the implementation of alloying engineering to improve intrinsic *** article compares the effects and mechanisms of alloying engineering on the optimization of the energy band structure and carrier behavior of BiOX,and lists various modification methods used to improve the optimization of the intrinsic properties by alloying engineering,including defect engineering,morphology control as well as the synergy between alloying and other modification methods(bismuth-rich strategies,cation doping,construction of heterojunctions and plasma resonance effects).Subsequently,applications of alloyed BiOX in energy and environmental fields are summarized,including contaminant degradation,antibacterial,CO_(2.reduction,nitrogen fixation and organic ***,we summarize the current challenges and future directions of alloyed *** is expected that this work will provide guidance and assistance for an in-depth study and understanding of the mechanisms of alloying engineering to optimize intrinsic properties and design alloyed BiOX with higher photocatalytic activity.

关键词： Bismuth oxyhalide Photocatalytic Alloyed engineering Microstructural regulation Application

Evolution of microstructure and texture of AZ80 magnesium alloy under hot torsion with constant decreasing temperature rate

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Journal of Magnesium and Alloys 2024年第4期12卷 1619-1637页

作者： Yongbiao Yang Jinxuan guo Cuiying Wang Wenxuan Jiang Zhimin zhang Qiang Wang Xing zhang College of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxi 030051China North Hongyang mechanical and electronic limited company of Henan Province China

Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-2.0℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the *** results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2.5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2.to ***,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller ***,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain ***,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also ***,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and *** torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.

关键词： Texture Microstructure Hot torsion Decreasing temperature AZ80

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-guo WU Guang-Ren DUAN Yu WANG Jie zhang School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

Pomegranate-like ATO/SiO_(2.microspheres for efficient microwave absorption in wide temperature spectrum

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Journal of Materials Science & Technology 2024年第7期174卷 195-203页

作者： Zhiyang Jiang Yanjie Gao Zhihao Pan Miaomiao zhang Jianhui guo Jingwei zhang Chunhong Gong Institute of Functional Polymer Composites College of Chemistry and Molecular SciencesHenan UniversityKaifeng 475004China National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004China

High-performance microwave-absorbing materials(MAMs)should meet both impedance matching and attenuation ***,it is hard to maintain excellent microwave absorption(MA)per-formance at an elevated temperature because the reliance on impedance matching and dielectric loss about temperature mutually *** this work,the pomegranate-like antimony-doped tin dioxide(ATO)/silica dioxide(SiO_(2.)spheres were fabricated via a simple spray drying *** the spheres were used as functional units and dispersed in the matrix,the corresponding composites exhibit an out-standing anti-reflection effect on ***,the unique pomegranate-like structure of the ATO/SiO_(2.spheres provides both the effective local eddy current and abundant heterogeneous interface,which therefore contribute harvest enhanced dielectric relaxation and improved absorption performance when compared with that of the corresponding ATO/SiO_(2.*** a result,the maximum re-flection loss of the ATO/SiO_(2.spheres composites can reach-47.8 dB at 9.7 GHz with a thickness of 1.8 mm,while the reflection loss could reach-47.3 dB at 573 K and the effective absorption bandwidth is 2.4 *** work reveals the importance of local eddy current loss in optimizing the electromagnetic wave(EMW)absorption performance and impedance matching,providing novel guidance on designing advanced high-temperature MAMs.

关键词： ATO/SiO_(2.microspheres Local eddy current Impedance matching Dielectric loss Microwave absorption

Ultralow-phase-noise and broadband frequency-hopping coupled optoelectronic oscillator under quiet point operation

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Photonics Research 2024年第8期12卷 1785-1793页

作者： HUI LIU MINGYANG guo TIAN zhang JIAN DAI KUN XU State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Advancements in microwave photonics have yielded novel approaches for generating high-purity microwave *** these,optoelectronic oscillators(OEOs)and coupled optoelectronic oscillators(COEOs)have demonstrated the capability to generate frequency-independent microwaves with exceptionally low phase ***,the tunability of the oscillators is rather limited due to the necessity for narrowband electronic bandpass filters,presenting challenges in achieving both wide and rapid tuning ***,we present a COEO featuring ultralow phase noise,flexible tuning capability,and high *** is achieved through a quiet point(QP)-operated harmonic mode-locked fiber laser,which effectively mitigates optical amplifier noise and supermode competition,thus significantly diminishing the necessity for ultra-narrow electronic *** to the liberated tuning ability,we present an oscillator that can be tuned from 2.GHz to 18 GHz,with phase noise as low as-140 d Bc/Hz at 10 k Hz under the QP *** then illustrate the practical application of the proposed oscillator in generating frequency-hopping signals with consistent spurious modes less than-85 d Bc,absolute phase noise below-135 d Bc/Hz at 10 k Hz,hopping resolution of 1.2. MHz,and fractional frequency stability below 6.1×10^(-12.at 1 s averaging time when locked to a *** presented COEO structure emerges as a compelling solution for agile and low-noise microwave sources in advanced wireless communication and radar systems.

关键词： optoelectronic tuning amplifier

Estimate pose deviation of on-orbit deployable mechanisms based on cross-ratio invariability

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Chinese Journal of Aeronautics 2024年第10期37卷 483-492页

作者： Peiran zhang Fuqiang ZHOU Zhipeng SONG Wentao guo Haishu TAN School of Instrumentation and Optoelectronic Engineering Beihang UniversityBeijing 100191China School of Physics and Optoelectronic Engineering Foshan UniversityFoshan 528225China

With the rapid development of space science projects,large deployable mechanisms have been widely ***,due to the effects of mechanical friction and gravitational acceleration,on-orbit mechanisms cannot be always deployed to the expected *** some precision optical mechanisms,even a minor deviation can result in significant error,so it needs to be measured and *** this paper,the deployment process was modeled and simplified as rotation under single-rotation-axis constraint and translation under single-direction *** solve the problem,a method based on cross-ratio invariability was *** proposed method does not rely on camera calibration techniques,as well as artificial marking points,both of which are necessary in ***,only three calibration images before launch and a measurement image on orbit were *** and experiments demonstrated that the proposed method is more accurate than *** addition,experiments also proved that the feasibility of the proposed method under dark conditions with the aid of a light source and some reflective marking points.

关键词： Cross-ratio invariability Deployable mechanism Pose deviation estimation Single-DOF constraint Vision measurement

Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1552-1564页

作者： Zheming zhang Jian Ji Xiangfeng guo Siang Huat Goh Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Department of Civil and Environmental Engineering National University of SingaporeSingapore

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial *** overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil *** three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-Lind-Rackwits-Fiessler recursive algorithm(iHLRF)as well as its inverse analysis *** proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face *** demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random *** results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into ***,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil *** results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic *** is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex

关键词： Limit analysis Tunnel face stability Spatial variability HLRF algorithm Inverse reliability method

Current observation and analysis based on mooring systems in the Andaman Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 484-491页

作者： Yimeng WANG Jingsong guo Dapeng QU Zhixin zhang Chalermrat SANGMANEE Varintha VASINAMEKHIN Binghuo guo First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China Phuket Marine Biological Center Department of Marine and Coastal ResourcesPhuket 83000Thailand Marine and Coastal Resources Research&Development Institute Department of Marine and Coastal ResourcesBangkok 10210Thailand

The basic structure and intraseasonal evolution of currents in the southeastern Andaman Sea was analyzed based on data collected in 2.17 from two subsurface moorings(C1 and C5).Periodic variation in the upper ocean currents of the Andaman Sea was investigated by combining observational and satellite *** observations show that rapid changes of current speed and direction occurred in May and June,with a significant increase in current velocity at the C1 *** the second half of the year,southward flow dominated at the C1 mooring,and alternating northward and southward flows were evident at the C5 mooring during the same period but the northward flow prevailed in boreal *** addition,analysis of the power spectra of the upper currents revealed that the tidal period at both moorings is primarily semidiurnal with weaker energy than that of the low-frequency *** upper ocean currents at the C1 and C5 moorings exhibited intraseasonal variation of 30-60 d and 12. d,while the zonal current at the C1 mooring exhibited a notable period of approximately 180 *** analysis indicated that the variability of currents in the Andaman Sea is influenced primarily by equatorial Kelvin waves and Rossby wave ***,our results suggest that equatorial Kelvin waves from the eastern Indian Ocean entered the Andaman Sea in the form of Wyrtki Jets and propagated primarily along two distinct pathways during the observation *** addition to coastal boundary Kelvin waves,it was found that a branch of the Wyrtki Jet that directly enters the Andaman Sea and flows northward along the slope of the continental shelf,and reflected Rossby wave packets by topography.

关键词： mooring observation Wyrtki Jet Rossby waves intraseasonal variation

C_(60) as a metal-free catalyst for lithium-oxygen batteries

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Nano Research 2024年第5期17卷 3982-3987页

作者： Xinxin zhang Jiaming Tian Yu Wang Shaohua guo Yafei Li Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional MaterialsNational Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresFrontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China

Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited density of active *** we present C_(60) as a metal-free cathode catalyst for LOBs,using density functional theory calculations and experimental *** lithiation reactions on the pristine carbon sites of C_(60) are energetically favorable due to its curvedπ-conjugation over the pentagon-hexagon *** kinetic analysis specifically reveals low energy barriers for Li_(2.O_(2. decomposition and Li diffusion on C_(60).Consequently,C_(60) exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon *** electrochemical measurements validate the predictions,notably demonstrating that the intrinsic activity of C_(60) is comparable to that of noble metals.

关键词： lithium-oxygen batteries C_(60) density functional theory(DFT)calculations metal-free cathode