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Investigation of stress distribution and damage behavior caused by forced installation of a composite bolted joint with a hole-location error

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Chinese Journal of Aeronautics 2024年第1期37卷 201-217页

作者： Chinan LIU Yuan LI Yi CHENG An’an ZHAO Kunpeng DU Yue SHI Ximing LI Hui CHENG School of Mechanical engineering Northwestern Polytechnical UniversityXi’an 710072China AVIC Xi’an Aircraft Industry group Company LTD Xi’an 710089China

In this paper,the influence of forced installation caused by a hole-location error on the 3D stress distribution and damage of a composite bolted joint is *** analytical model of stress distributed on composite holes is promoted,in view of non-uniform extrusion caused by forced *** first,non-uniform extrusion of the hole edge caused by forced installation is *** to the contact state,expression of hole deformation is ***,based on Hertz theory,the maximum extrusion load is obtained with help of deformation *** constructing an elastic foundation beam model,3D stress distributed on a hole could be analyzed according to the extrusion ***,stress distribution predicted by the above analytical method is compared with that provided by FE considering composite ***,a forced installation experiment is carried out to analyze the damage distribution of the *** show that a central-symmetrically distributed stress is introduced by the hole-location *** an increment of the error,strength of composite decreases due to extrusion ***,stress presents a concave distribution on the *** the hole-location error exceeding 3%,stress decreases gradually due to failure of *** of holes does not exhibit a centrosymmetric *** damage is mainly distributed on the entrance of the hole at the lower sheet.

关键词： Hole-location error Composite joint Forced installation Stress distribution Damage

Experimental Study on engineering Behavior of Solidified Soil for Scour Repair and Protection

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China Ocean engineering 2024年第4期38卷 625-635页

作者： WU Xiao-ni LI Ru-yu SHU Jian TANG Chao CHEN Jin-jian WANG Hui-li JIANG Hai-li WANG Xiao State Key Laboratory of Ocean engineering Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China Shanghai Road and Bridge group Co. Ltd.Shanghai 200433China Shanghai engineering research Center of Urban Infrastructure Renewal Shanghai 200032China Jiangsu Kunze Technology Co. Ltd.Nanjing 210000China

A new scour countermeasure using solidified slurry for offshore foundation has been proposed *** solidified slurry is pumped to seabed area around foundation for scour protection or pumped into the developed scour holes for scour repair as the fluidized material solidifies *** the pumping operation and solidification,the engineering behaviors of solidified slurry require to be considered synthetically for the reliable application in scour repair and protection of ocean engineering such as the pumpability related flow value,flow diffusion behavior related rheological property,anti-scour performance related retention rate in solidification and bearing capacity related strength property after *** this study,a series of laboratory tests are conducted to investigate the effects of mix proportion(initial water content and binder content)on the flow value,rheological properties,density,retention rate of solidified slurry and unconfined compressive strength(UCS).The results reveal that the flow value increases with the water content and decreases with the binder *** the solidified slurry exhibits Bingham plastic behavior when the shear rate is larger than 5 s^(-1).The Bingham model has been employed to fit the rheology test results,and empirical formulas for obtaining the density,yield stress and viscosity are established,providing scientific support for the numerical assessment of flow and diffusion of solidified *** rate of solidified slurry decreases with the water flow velocity and flow value,which means the pumpability of solidified slurry is contrary to anti-scour *** unconfined compressive strength after solidification reduces as the water content increases and binder content decreases.A design and application procedure of solidified soil for scour repair and protection is also proposed for engineering reference.

关键词： scour repair and protection solidified soil pumpability strength flow properties anti-scour performance

Improving flangeability of multiphase steel by increasing microstructural homogeneity

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Journal of Iron and Steel research(International) 2024年第7期31卷 1736-1745页

作者： Xiao-yu Yang Yong-gang Yang Xing Fang Han-long Zhang Zhen-li Mi Beijing Advanced Innovation Center for Materials Genome engineering Institute of Engineering TechnologyUniversity of Science and Technology BeijingBeijing 100083China Shanghai Baosteel group Corp.Technology Center Shanghai 201900China

Multiphase microstructure significantly increases the strength,usually at the expense of flangeability because of lacking microstructure *** further improve the strength-flangeability of multiphase steel,the microstructural homogeneity was advanced by adjusting the hard martensite/austenite(M/A)*** strength-flangeability was measured via uniaxial tensile tests and hole expansion *** microstructures were characterized using a scanning electron microscope equipped with an electron backscatter diffraction detector and a transmission electron *** tests were supplementally used to quantitatively reveal the microstructural homogeneity of the *** show that the adjusted multiphase steel achieves an excellent ultimate tensile strength(~800 MPa)and flangeability(~135%hole expansion ratio).A promising homogeneous multiphase microstructure was obtained by controlling undercooled austenite transformed at about 600℃.This microstructure consists of soft polygonal ferrite,blocky bainitic ferrite,and hard M/A *** volume fraction of M/A islands is around 5%,and the average size is less than l *** nanoindentation analysis indicated that the participation of M/A islands impressively influenced the microstructural *** strain partition and better mechanical compatibility were present in the adjusted multiphase steel since the plasticity initiation started late,which resulted in a positive ***,avoiding M/A islands distributed in the chain along the rolling direction on the matrix hindered the possibility of voids coalescing into cracks and stabilized the flanging performance.

关键词： Multiphase steel Flangeability Martensite/austenite island-Microstructural homogeneity-Microstructure Compact strip production process

Plasma-assisted aerogel interface engineering enables uniform Zn^(2+)flux and fast desolvation kinetics toward zinc metal batteries

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Journal of Energy Chemistry 2024年第8期95卷 29-38,I0002页

作者： Zijian Xu Zhenhai Shi Zhan Chang Fan Feng Zhuanyi Liu Dongkun Chu Jianguo Ren Zi-Feng Ma Suli Chen Tianxi Liu Key Laboratory of Synthetic and Biological Colloids Ministry of Education School of Chemical and Material EngineeringJiangnan UniversityWuxi 214122JiangsuChina Shanghai Electrochemical Energy Devices research Center Department of Chemical EngineeringShanghai Jiao Tong UniversityShanghai 200240China BTR New Material group Co. LTD.Shenzhen 518000GuangdongChina

The poor reversibility of Zn anodes induced by dendrite growth,surface passivation,and corrosion,severely hinders the practical applicability of Zn metal *** address these issues,a plasmaassisted aerogel(PAG)interface engineering was proposed as efficient ion transport modulator that can simultaneously regulate uniform Zn^(2+)flux and desolvation behavior during battery *** PAG with ordered mesopores acted as an ion sieve to homogenize Zn deposition and accelerate Zn^(2+)flux,which is favorable for corrosion resistance and dendrite ***,the plasma-assisted aerogel with abundant hydrophilic groups can facilitate the desolvation kinetics of Zn^(2+)due to the multiple hydrogen-bonding interaction with the activated water molecules,thus accelerating the Zn^(2+)migration ***,the Zn/Zn cell assembled with PAG-modified separator demonstrates stable plating and stripping behavior(over 1400 h at 1 mA cm^(-2))and high Coulombic efficiency(99.8%at1 mA cm^(-2)after 1100 cycles),and the Zn‖MnO_(2)full cell shows excellent long-term cycling stability and maintains a high capacity of 154.9 mA h g^(-1)after 1000 cycles at 1 A g^(-1).This study provides a feasible approach for the large-scale fabrication of aerogel functionalized separators to realize ultra-stable Zn metal batteries.

关键词： Zn metal batteries Aerogel interface Plasma Zn^(2+)migration kinetics Dendrite growth

Performance Enhancement of Parabolic Trough Collector by Using Homogenizer and Spiral

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Journal of Thermal Science 2024年第2期33卷 658-674页

作者： LI Peijing LIU Taixiu QIN Yuanlong ZHENG Zhimei ZHAO Kai LIU Qibin School of Energy Powerand Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China Institute of engineering Thermophysics Chinese Academy of SciencesBeijing100190China University of Chinese Academy of Science Beijing100049China Department of Thermal Science and Energy engineering University of Science and Technology of ChinaHefei230027China research Institute of Science and Technology of China Three Gorges group Corporation Beijing100038China

In conventional parabolic trough collectors(PTCs),sunlight is concentrated at the bottom of the absorber tube,resulting in a significant circumferential temperature gradient across the absorber tube,heat loss and thermal deformation,which affects the safety and thermal performance of *** this study,a new receiver with homogenizer and spiral(RHS) is proposed,achieving the optical and thermal synergy to ameliorate the thermal deformation of the absorber tube and enhance thermal efficiency.A plane structure homogenizer is designed to improve uniformity of the concentrated solar flux of absorber tube through second *** combination with the spiral,it improves the optical-thermal efficiency of the PTC by enhancing heat exchange between the fluid and the backlight side of the absorber *** performance of the collector is numerically studied by building a three-dimensional coupled light-thermal-structure *** results show that the thermal deformation of the RHS is reduced by more than 96% and the optical-thermal efficiency is improved by 1.2%-0.63% compared with conventional receivers(CRs) under the same inlet temperature *** proposed receiver is validated to be effective in reducing thermal deformation and improving optical-thermal efficiency.

关键词： parabolic trough collector homogenizer thermal deformation spiral

Properties of Ultra-low Thermal Expansion LAS Transparent Glass-ceramics Prepared by Spodumene

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Journal of Wuhan University of Technology(Materials Science) 2024年第3期39卷 541-550页

作者：何峰何子君 ZHOU Zhiqiang TIAN Yingliang ZHAO Zhiyong School of Materials Science and engineering Beijing University of TechnologyBeijing 100124China Department of Functional Material research Central Iron and Steel Research InstituteBeijing 100081China School of Materials Science and engineering Wuhan University of TechnologyWuhan 430070China National engineering research Center of FPD Glass Technology Xianyang 712000China

The glass-ceramics were prepared with the spodumene mineral as the main raw material,and the effects of ZrO_(2)replacing TiO_(2)on the samples were systematically *** results show that the substitution of ZrO_(2)for TiO_(2)is not conductive to precipitate𝛽β-quartz solid solution phase,but can improve the transparency and flexural strength of *** the glass-ceramic with the highest visible light transmittance(87%)and flexural strength(231.80 MPa)exhibits an ultra-low thermal expansion of-0.028×10^(-7)K^(-1)in the region of 30-700℃.

关键词： ultra-low thermal expansion LAS transparent glass-ceramics substitution of ZrO_(2)for TiO_(2) spodumene mineral

Selective photocatalytic oxidation of methane to C1 oxygenates by regulating sizes and facets over Au/ZnO

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Nano research 2024年第5期17卷 3810-3818页

作者： Qiang Zhou Xinyu Wang Xiaojie Tan Qinhua Zhang Hao Yang Tao Xing Mingqing Wang Mingbo Wu Wenting Wu State Key Laboratory of Heavy Oil Processing College of Chemistry and Chemical Engineering&Institute of New EnergyChina University of Petroleum(East China)Qingdao 266580China National engineering research Center of Coal Gasification and Coal-Based Advanced Materials ShanDong Energy Group CO.LTDJinan 250101China

Photocatalytic oxidation of methane to value-added chemicals is a promising process under mild conditions,nevertheless confronting great challenges in efficiently activating C-H bonds and inhibiting ***,we propose a comprehensive strategy for the selective generation of reactive oxygen species(ROS)by regulating the sizes and facets of Au nanoparticles loaded on *** photocatalytic methane oxidation at ambient temperature,a high oxygenates yield of 36.4 mmol·g^(-1)·h^(-1) with a nearly 100%selectivity has been achieved over the optimized 1.0%Au/ZnO-9.6(1%Au with(111)facet and 9.6 nm size on ZnO)photocatalyst,exceeding most reported *** investigations reveal that 1.0%Au/ZnO-9.6 with the medium size and Au(111)facet guarantees the favourable formation of superoxide radicals(·OOH)through mild oxygen reduction,ultimately leading to excellent photocatalytic methane oxidation *** work provides some guidance for the delicate design of photocatalysts for efficient photocatalytic methane oxidation and oxygen utilization.

关键词： photocatalysis methane oxidation radical regulation oxygen activation nanomaterial

Detection of onset of agglomeration in a bubbling fluidized bed biomass combustor using reactive Eulerian computational fluid dynamics

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Particuology 2024年第7期90卷 504-515页

作者： Abdullah Tasleem Atta Ullah Fei Li Qun Yi William Nimmo Syed Sheraz Daood Department of Chemical engineering Pakistan Institute of Engineering and Applied Sciences(PIEAS)Lehtrar RoadP.O.Nilore45650IslamabadPakistan Institute of Process engineering Chinese Academy of SciencesBeijing100190China School of Chemical engineering and Pharmacy Wuhan Institute of TechnologyWuhan430205China Energy engineering group Energy 2050Department of Mechanical EngineeringUniversity of SheffieldSheffieldS37RDUnited Kingdom Institute of Energy and Environmental engineering Faculty of ElectricalEnergy&Environmental EngineeringUniversity of the PunjabQuaid-e-Azam CampusLahorePakistan Energy engineering research and Development Centre Faculty of ElectricalEnergy&Environmental EngineeringUniversity of the PunjabQuaid-e-Azam CampusLahorePakistan

The choice of a type of combustion technology to be used for heat or power generation depends on economic,technical,operational and fuel availability *** benefits associated with the evolving market driven by the fluidised bed combustion(FBC)technology cannot be overlooked especially when gauged at 65 GWth of worldwide installed capacity alongside added benefits of handling fuel variation,low pollutant emissions and high combustion *** or biomass waste will continue to have a vital role to play in the future FBC technology-based power *** often contains high levels of inorganic species that can form sticky agglomerates posing a significant risk to boiler operation resulting in unscheduled *** added complexity of the behaviour of the fuel and bed material mix highlights the requirement for simulation models to identify agglomeration to help improve the overall performance and reliability of FBC *** resolve this problem,this research devised a simulation strategy for the detection of agglomeration using the Eulerian–Eulerian *** developed modelling strategy is validated with the experimental data available in literature for two-dimensional simplified geometry of a pilot-scale fluidised bed *** model results were found promising and robust to predict bed defluidisation times and other parameters consistent with the experimental data.

关键词： Fluidized bed combustion Eulerian Models Biomass Agglomeration Defluidisation

An intelligent control method based on artificial neural network for numerical flight simulation of the basic finner projectile with pitching maneuver

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Defence Technology（防务技术） 2024年第2期32卷 663-674页

作者： Yiming Liang Guangning Li Min Xu Junmin Zhao Feng Hao Hongbo Shi Northwestern Polytechnical University School of Astronautics Xi’an 710072China China North Industries group Corporation No 203 research Institute Xi’an 710065China

In this paper,an intelligent control method applying on numerical virtual flight is *** proposed algorithm is verified and evaluated by combining with the case of the basic finner projectile model and shows a good application ***,a numerical virtual flight simulation model based on overlapping dynamic mesh technology is *** order to verify the accuracy of the dynamic grid technology and the calculation of unsteady flow,a numerical simulation of the basic finner projectile without control is carried *** simulation results are in good agreement with the experiment data which shows that the algorithm used in this paper can also be used in the design and evaluation of the intelligent controller in the numerical virtual flight ***,combined with the real-time control requirements of aerodynamic,attitude and displacement parameters of the projectile during the flight process,the numerical simulations of the basic finner projectile’s pitch channel are carried out under the traditional PID(Proportional-Integral-Derivative)control strategy and the intelligent PID control strategy *** intelligent PID controller based on BP(Back Propagation)neural network can realize online learning and self-optimization of control parameters according to the acquired real-time flight *** with the traditional PID controller,the concerned control variable overshoot,rise time,transition time and steady state error and other performance indicators have been greatly improved,and the higher the learning efficiency or the inertia coefficient,the faster the system,the larger the overshoot,and the smaller the stability *** intelligent control method applying on numerical virtual flight is capable of solving the complicated unsteady motion and flow with the intelligent PID control strategy and has a strong promotion to engineering application.

关键词： Numerical virtual flight Intelligent control BP neural network PID Moving chimera grid