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Acta Mechanica Sinica 2008年第6期24卷 709-720页

作者： f.h.zhu .M.fu College of Mechanics and Aerospace Hunan University410082 ChangshaChina

By considering the effect of interfacial damage and using the variation principle, three-dimensional nonlinear dynamic governing equations of the laminated plates with interfacial damage are derived based on the general sixdegrees-of-freedom plate theory towards the accurate stress analysis. The solutions of interlaminar stress and nonlinear dynamic response for a simply supported laminated plate with interfacial damage are obtained by using the finite difference method, and the results are validated by comparison with the solution of nonlinear finite element method. In numerical calculations, the effects of interfacial damage on the stress in the interface and the nonlinear dynamic response of laminated plates are discussed.

关键词： Laminated plates Geometric nonlinearity Accurate stress analysis Interfacial damage Interlaminar stress Nonlinear dynamic response

Multi-Objective optimization for stable and efficient cargo transportation of partial space elevator

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Defence Technology(防务技术) 2025年第2期44卷 17-29页

作者： Gefei Shi Zheng h.zhu School of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510275China Shenzhen Key Laboratory of Intelligent Microsatellite Constellation Shenzhen 518107China Department of Mechanical Engineering York University4700 Keele StreetTorontoCanada

This paper proposed a new libration decoupling analytical speed function(LD-ASf)in lieu of the classic analytical speed function to control the climber's speed along a partial space elevator to improve libration stability in cargo *** LD-ASf is further optimized for payload transportation efficiency by a novel coordinate game theory to balance competing control objectives among payload transport speed,stable end body's libration,and overall control input via model predictive *** transfer period is divided into several sections to reduce computational *** validity and efficacy of the proposed LD-ASf and coordinate game-based model predictive control are demonstrated by computer *** results reveal that the optimized LD-ASf results in higher transportation speed,stable end body's libration,lower thrust fuel consumption,and more flexible optimization space than the classic analytical speed function.

关键词： Partial space elevator Stable transportation Libration decoupling analytical speed function Coordinate game Model predictive control Pareto optimization

Plant-substrate biochar properties critical for mediating reductive debromination of 1,2-dibromoethane

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Journal of Environmental Sciences 2025年第1期147卷 1-10页

作者： Jonathan h.Lindhardt Peter E.holm Yong-Guan zhu Changyong Lu hans Christian B.hansen Department of Plant and Environmental Sciences Faculty of ScienceUniversity of CopenhagenThorvaldsensvej 401871 Frederiksberg CDenmark Key lab of Urban Environment and health Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Sino-Danish Center for education and research China and DenmarkDalgas Avenue 4DK-8000 Aarhus C.Denmark

Dibromoethane is a widespread,persistent organic *** are known mediators of reductive dehalogenation by layered fe^(Ⅱ)-fe^(Ⅲ)hydroxides(green rust),which can reduce 1,2-dibromoethane to innocuous bromide and ***,the critical characteristics that determine mediator functionality are lesser *** biochar substrates were pyrolyzed at 600℃and 800℃,characterized by elemental analysis,X-ray photo spectrometry C and N surface speciation,X-ray powder diffraction,specific surface area analysis,and tested for mediation of reductive debromination of 1,2-dibromoethane by a green rust reductant under anoxic conditions.A statistical analysis was performed to determine the biochar properties,critical for debromination kinetics and total debromination *** was shown that selected plant based biochars can mediate debromination of 1,2-dibromoethane,that the highest first order rate constant was 0.082/hr,and the highest debromination extent was 27%in reactivity experiments with 0.1μmol(20μmol/L)1,2-dibromoethane,≈22 mmol/L fe^(Ⅱ)GR,and 0.12 g/L soybean meal biochar(7 days).Contents of Ni,Zn,N,and P,and the relative contribution of quinone surface functional groups were significantly(ph 1,2-dibromoethane debromination,while adsorption,specific surface area,and the relative contribution of pyridinic N oxide surface groups were significantly negatively correlated with debromination.

关键词： Environmental remediation Biochar Persistent organic pollutants(POPs) Environmental catalysis Green rust

Spatial confinement:An effective strategy to improve h_(2)O and SO_(2) resistance of the expandable graphite-modified TiO_(2)-supported Pt nanocatalysts for CO oxidation

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Journal of Environmental Sciences 2025年第2期148卷 57-68页

作者： hongtai zhu Wenge Qiu RuiWu Kai Li hong he Key Laboratory of Beijing on Regional Air Pollution Control Beijing Key Laboratory for Green Catalysis and SeparationBeijing University of TechnologyBeijing 100124China Advanced E-Catal.Corporation Ltd.Beijing 100025China

The expandable graphite(EG)modified TiO_(2) nanocomposites were prepared by the high shearmethod using the TiO_(2) nanoparticles(NPs)and EG as precursors,in which the amount of EG doped in TiO_(2) was 10 wt.%.followed by the impregnation method,adjusting the ph of the solution to 10,and using the electrostatic adsorption to achieve spatial confinement,the Pt elementswere mainly distributed on the exposed TiO_(2),thus generating the Pt/10EG-TiO_(2)-10 *** best CO oxidation activity with the excellent resistance to h_(2)O and SO_(2) was obtained over the Pt/10EG-TiO_(2)-10 catalyst:CO conversion after 36 hr of the reaction was ca.85%under the harsh condition of 10 vol.%h_(2)O and 100 ppm SO_(2) at a high gaseous hourly space velocity(GhSV)of 400,000 hr−*** properties of the catalystswere characterized by various *** results showed that the electrostatic adsorption,which riveted the Pt elements mainly on the exposed TiO_(2) of the support surface,reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs,hence significantly improving CO oxidation activity over the Pt/10EG-TiO_(2)-10 *** 10 wt.%EG doped in TiO_(2) caused the TiO_(2) support to form a more hydrophobic surface,which reduced the adsorption of h_(2)O and SO_(2) on the catalyst,greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO_(2),thus resulting in an improvement in the resistance to h_(2)O and SO_(2) of the Pt/10EG-TiO_(2)-10 catalyst.

关键词： Expandable graphite Electrostatic adsorption Titania supported platinum CO oxidation Resistance to h_(2)O and SO_(2)

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中国海南岛生物区系起源的新认识

中国科学:地球科学 2025年第1期55卷 52-61页

作者：朱华中国科学院西双版纳热带植物园综合保护中心云南省东南亚生物多样性保护国际联合实验室云南省热带雨林与亚洲象保护重点实验室勐腊666303

中国海南岛的生物区系起源是一个引人探索的基本科学问题.地质学、古地磁学和生物区系比较研究曾提出“海南岛在始新世时连接着越南和广西,后来发生了向东南的移动,最终到达了现在位置”的观点.本文从海南岛生物类群的分子系统发育和古... 详细信息

中国海南岛的生物区系起源是一个引人探索的基本科学问题.地质学、古地磁学和生物区系比较研究曾提出“海南岛在始新世时连接着越南和广西,后来发生了向东南的移动,最终到达了现在位置”的观点.本文从海南岛生物类群的分子系统发育和古植物学研究例证,支持海南岛在始新世时可能连接着越南和广西.海南岛生物类群的基因组、系统发育和分子生物地理学研究揭示的生物地理格局显示,分化时间较早(中新世以前)的属和种,用海南岛在始新世时连接着越南和广西能较好地解释.根据东南亚地质板块重建理论,中新世中期(约15Ma前),海南岛已向东南移动到了现在的位置,对分化时间较晚的类群,如物种的种群和遗传分化,可用海南岛已与大陆的雷州半岛接近以及有了密切的陆地连接合理解释,但并不都是如此.古植物学研究揭示在始新世-渐新世时中国西南部和海南岛具有一个亚热带性质的植被和植物区系,但中国东南部(茂名)晚始新世群显示了具有热带雨林植被和植物区系,暗示海南岛在古近纪时可能位于靠近或接壤广西西南部和越南北部的位置.植物区系研究揭示了海南的植物区系分区基本上呈东北-西南倾斜分布格局,这与古地磁学研究提出的海南岛向东南移动过程中发生了逆时针旋转可以互为印证.本文是在地质学和生物区系比较研究提出的海南岛起源观点的基础上,从分子系统发育、古植物学研究及海南植物多样性分布格局多学科结合上进一步论证海南岛生物区系的起源与演化,提出了演化的时间节点是在中新世,为深入探讨海南岛生物区系的起源与演化提供依据.

关键词：分子系统发育生物地理古植物学生物区系起源海南岛

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Co_(0.5)Zn_(0.5)fe_(2)O_(4)modified residual carbon as an excellent microwave absorber

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International Journal of Minerals,Metallurgy and Materials 2025年第3期32卷 534-545页

作者： Yuanchun Zhang Dacheng Ma Xingzhao Zhang Chuanlei zhu Shengtao Gao School of Chemical and Blasting Engineering Anhui University of Science and TechnologyHuainan 232001China Joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan 232001China

Microwave absorbers have great potential for military and civil ***,Co_(0.5Z)n_(0.5)fe_(2)O_(4)/residual carbon(CZfO/RC)composites have been successfully prepared using a hydrothermal *** was derived from coal gasification fine slag(CGfS)via pickling,which removes inorganic *** test means have been used to study the chemical composition,crys-tal structure,and micromorphology of the CZfO/RC composites,as well as their electromagnetic parameters and microwave absorption(MA)*** CZfO/RC composites exhibit excellent MA performance owing to their dielectric and magnetic *** the thickness of CZfO/RC-2(feCl_(3)·6h_(2)O of 0.007 mol,ZnCl_(2)of 0.00175 mol,and CoCl_(2)·6h_(2)O of 0.00175 mol)is 1.20 mm,the minimum reflection loss(RL_(min))is-56.24 dB,whereas at a thickness of 3.00 mm and 6.34 Ghz,RL_(min) is-45.96 dB and the maximum effective ab-sorption bandwidth is 1.83 Ghz(5.53-7.36 Ghz).Dielectric loss includes interface and dipole polarizations,while magnetic loss includes current and remnant magnetic ***/RC-2 exhibits high impedance matching,allowing microwave to enter the *** com-puter simulation technology confirms that CZfO/RC-2 considerably decreases the radar *** study can be used to promote the use of CGfS as electromagnetic wave(EMW)-absorbing materials.

关键词： cobalt-zinc ferrite residual carbon microwave absorption coal gasification fine slag coal-based solid waste

Recent progress on non-metallic carbon nitride for the photosynthesis of h_(2)O_(2):Mechanism,modification and in-situ applications

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Chinese Chemical Letters 2025年第1期36卷 165-175页

作者： hao Lv Zhi Li Peng Yin Ping Wan Mingshan zhu College of Environment and Climate Jinan UniversityGuangzhou 511443China Jiading Branch of Shanghai General hospital Shanghai Jiao Tong University School of MedicineShanghai 201803China Department of Liver Surgery Ren Ji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China

Photocatalytic hydrogen peroxide(h_(2)O_(2))production has been considered as a promising strategy for h_(2)O_(2)synthesis due to its environmentally *** various photocatalysts,carbon nitride-based materials are excellent candidates for h_(2)O_(2)production because of their excellent visible-light response,low cost and high *** this review,we summarize in detail the research progress on the photocatalytic production of h_(2)O_(2)by carbon ***,we summarize the basic principles of photocatalysis and photocatalytic h_(2)O_(2)***,the classification and modification methods of carbonnitride-based materials are discussed,including morphology modulation,noble metal loading,defect control,heterojunction regulation,molecular structure engineering and elemental ***,the different in-situ applications of h_(2)O_(2)via photosynthesis were discussed,including disinfection and antibiotic resistant genes degradation,organic pollutants degradation,medical applications and fine chemical *** review brings great promise for in-situ h_(2)O_(2)photosynthesis,which is expected to serve as a key component in future applications.

关键词： Carbon nitride hydrogen peroxide Photocatalysis Applications

Gas-Solid flow,Combustion Characteristics,and Gas Emissions in a 75 t/h CfB Boiler Based on the CPfD Method

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Journal of Thermal Science 2025年第1期34卷 323-336页

作者： hUANG Xiankun BAI Zhang zhu Xiaoli WANG Shuoshuo MU Lin GONG Liang College of New Energy China University of Petroleum(East China)Qingdao 266580China Key Laboratory of Ocean Energy Utilization and Energy Conservation of Ministry of Education School of Energy and Power EngineeringDalian University of TechnologyDalian 116024China

A 3D simulation using Computational Particle fluid Dynamics(CPfD)methods was used to calculate coal combustion in a 75 t/h industrial-scale circulating fluidized bed(CfB)*** characteristics,gas-solid flow characteristics,and gaseous pollutant emissions of CfB boilers from combustion ignition to stable operation were systematically evaluated in this *** show that the temperature distribution is relatively uniform throughout the *** the combustion process unfolds within the boiler,the gas composition curve strikingly portrays the inverse correlation between CO_(2)and O_(2)*** the combustion reaction progresses,it becomes evident that the concentration of CO_(2)progressively increases,while the concentration of O_(2)concurrently *** inverse relationship underscores the fundamental combustion reaction,where carbon-based fuels react with oxygen to produce carbon dioxide and release ***,a comprehensive analysis has revealed that,from ignition to stable combustion,both nitric oxide(NO)and sulfur dioxide(SO_(2))emissions exhibit a declining *** reduction in pollutant generation is attributed to the improvement in combustion *** complete combustion leads to lower levels of unburned hydrocarbons,which are prone to NO ***,the sulfur content in the fuel is more efficiently oxidized to sulfur trioxide(SO_(3))or bound in sulfates,reducing SO_(2)*** steady state in the simulation,the SO_(2)mass flow rate varies significantly with the furnace height,gradually increasing from 0.07 kg·s^(-1)at 4 m at the bottom of the furnace to a peak of 0.078 kg·s^(-1)at 8 m in the center,and then decreasing to 0.06 kg·s^(-1)at 20m at the top of the furnace.

关键词： circulating fluidized bed particle flow combustion CPfD modeling

The controlled oxidation states of the h4PMo11VO40 catalyst induced by plasma for the selective oxidation of methacrolein

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Chinese Chemical Letters 2025年第02期36卷 189-194页

作者： Gang hu Chun Wang Qinqin Wang Mingyuan zhu Lihua Kang School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering Shihezi University College of Chemistry&Chemical Engineering Yantai University

In this paper,low-temperature dielectric-blocked discharge plasma （DBD） was employed for the first time to treat silica-doped h4PMo11VO40（hPAV） catalysts (DBD（Ar/x）-Mf-Catal) and apply them in the catalytic methacrolein （MAL） selective oxidation to produce methacrylic acid （MAA）.This work investigates in detail the controllable regulation of the concentration of oxidation states on silica-doped hPAV catalysts by adjusting the DBD discharge with controlled changes in voltage,current,treatment time,and treatment *** reports the intrinsic correlation between oxidation states and MAL oxidation *** research results indicated that the catalytic performance was related to the presence of oxygen vacancies and oxygen species (VO2+),and are the main reason for the selective oxidation of MAL to ***,the generation of oxygen vacancies and VO2+altered localized electrons,which resulted in the easier activation of *** calculations of DfT also proved the formation mechanism of oxygen vacancies and VO2+and electron properties on high-performance polymers,which elucidated the intrinsic influence of catalyst *** DBD（Ar/10）-Mf-Catal catalysts with suitable VO2+and oxygen vacancy concentrations exhibited the highest catalytic performance with 90%MAL conversion and 70%MAA selectivity and showed good stability （500 h）.

关键词： Catalyst Dopant Methacrolein Methacrylic acid Oxygen vacancy Plasma

Multiphoton photoredox catalysis enables selective hydrodefluorinations

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Chinese Chemical Letters 2025年第2期36卷 366-372页

作者： Jiaqi Jia Kathiravan Murugesan Chen zhu huifeng Yue Shao-Chi Lee Magnus Rueping KAUST Catalysis Center KCC King Abdullah University of Science and Technology

Late-stage modification of complex molecules via site-selective hydrodefluorination is a challenging endeavor. The selective activation of carbon-fluorine(C–f) bonds in the presence of multiple C–f bonds is of importance in organic synthesis and drug discovery. herein, we describe the activation of C-f bonds via multiphoton photoredox catalysis to selectively produces a series of hydrodefluorinated compounds by simply tuning the reaction conditions. Moreover, this protocol was successfully applied to the late-stage functionalization of different drug-derivatives and the corresponding mono-, di-, and tri-defluorinated products were obtained in good to excellent yields. A detailed mechanistic investigation provides insight into the unprecedented hydrodefluorination pathway.

关键词： C-f bond activation Multiphoton Photoredox catalysis Site-selectivity Trifluoroacetamide