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Inter-well internal resonance analysis of rectangular asymmetric cross-ply bistable composite laminated cantilever shell under transverse foundation excitation

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Applied Mathematics and Mechanics(English Edition) 2024年第8期45卷 1353-1370页

作者： Lele REN Wei zhang yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China

The chaotic dynamic snap-through and complex nonlinear vibrations are investigated in a rectangular asymmetric cross-ply bistable composite laminated cantilever shell,in cases of 1:2 inter-well internal resonance and primary *** transverse foundation excitation is applied to the fixed end of the structure,and the other end is in a free *** first-order approximate multiple scales method is employed to perform the perturbation analysis on the dimensionless two-degree-of-freedom ordinary differential motion control *** four-dimensional averaged equations are derived in both polar and rectangular coordinate *** from the obtained frequency-amplitude and force-amplitude response curves,a detailed analysis is conducted to examine the impacts of excitation amplitude,damping coefficient,and tuning parameter on the nonlinear internal resonance characteristics of the *** nonlinear softening characteristic is exhibited in the upper stable-state,while the lower stable-state demonstrates the softening and linearity *** simulation is carried out using the fourth-order Runge-Kutta method,and a series of nonlinear response curves are *** the excitation amplitude further elucidates the global bifurcation and chaotic dynamic snap-through characteristics of the bistable cantilever shell.

关键词： bistable composite laminated cantilever shell inter-well internal resonance primary resonance chaotic dynamic snap-through complex nonlinear vibration

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Snap-through behaviors and nonlinear vibrations of a bistable composite laminated cantilever shell:an experimental and numerical study

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 779-794页

作者： Lele REN Wei zhang Ting DONG yufei zhang State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200240China Department of Mechanics Guangxi UniversityNanning 530004China Beijing Key Laboratory of Nonlinear Vibrations and Strength of Mechanical Structures College of Mechanical EngineeringBeijing University of TechnologyBeijing 100124China School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China

The snap-through behaviors and nonlinear vibrations are investigated for a bistable composite laminated cantilever shell subjected to transversal foundation excitation based on experimental and theoretical *** improved experimental specimen is designed in order to satisfy the cantilever support boundary condition,which is composed of an asymmetric region and a symmetric *** symmetric region of the experimental specimen is entirely clamped,which is rigidly connected to an electromagnetic shaker,while the asymmetric region remains free of *** motion paths are realized for the bistable cantilever shell by changing the input signal levels of the electromagnetic shaker,and the displacement responses of the shell are collected by the laser displacement *** numerical simulation is conducted based on the established theoretical model of the bistable composite laminated cantilever shell,and an off-axis three-dimensional dynamic snap-through domain is *** numerical solutions are in good agreement with the experimental *** nonlinear stiffness characteristics,dynamic snap-through domain,and chaos and bifurcation behaviors of the shell are quantitatively *** to the asymmetry of the boundary condition and the shell,the upper stable-state of the shell exhibits an obvious soft spring stiffness characteristic,and the lower stable-state shows a linear stiffness characteristic of the shell.

关键词： bistable composite laminated cantilever shell snap-through behavior nonlinear vibration nonlinear stiffness characteristic chaos and bifurcation

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Corrosion behaviors and kinetics of nanoscale zero-valent iron in water:A review

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Journal of Environmental Sciences 2024年第1期135卷 391-406页

作者： Chenliu Tang Xingyu Wang yufei zhang Nuo Liu Xiang Hu Research Group of Water Pollution Control and Water Reclamation College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China Shanghai Collaborative Innovation Centre for WEEE Recycling School of Resources and Environmental EngineeringShanghai Polytechnic UniversityShanghai 201209China

Knowledge on corrosion behaviors and kinetics of nanoscale zero-valent iron(nZVI)in aquatic environment is particularly significant for understanding the reactivity,longevity and stability of nZVI,as well as providing theoretical guidance for developing a cost-effective nZVI-based technology and designing large-scale ***,this review gives a holistic overview on the corrosion behaviors and kinetics of nZVI in ***,Eh-pH diagram is introduced to predict the thermodynamics trend of iron *** morphological,structural,and compositional evolution of(modified-)nZVI under different environmental conditions,assisted with microscopic and spectroscopic evidence,is then ***,common analytical methods and characterization technologies are categorized to establish time-resolved corrosion kinetics of nZVI in ***,stable models for calculating the corrosion rate constant of nZVI as well as electrochemical methods for monitoring the redox reaction are discussed,emphasizing their capabilities in studying the dynamic iron corrosion ***,in the future,more efforts are encouraged to study the corrosion behaviors of nZVI in long-term practical application and further build nanoparticles with precisely tailored *** expect that our work can deepen the understanding of the nZVI chemistry in aquatic environment.

关键词： Nanoscale zero-valent iron(nZVI) Corrosion behaviors Corrosion kinetics nZVI evolution

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Prediction of the thermal conductivity of Mg–Al–La alloys by CALPHAD method

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 129-137页

作者： Hongxia Li Wenjun Xu yufei zhang Shenglan Yang Lijun zhang Bin Liu Qun Luo Qian Li State Key Laboratory of Advanced Special Steels&Shanghai Key Laboratory of Advanced Ferrometallurgy&School of Materials Science and Engineering Shanghai UniversityShanghai 200444China National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing 400044China State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China College of Materials Science and Engineering Chongqing UniversityChongqing 400044China National Key Laboratory of Advanced Casting Technologies Chongqing UniversityChongqing 400044China

Mg-Al alloys have excellent strength and ductility but relatively low thermal conductivity due to Al *** accurate prediction of thermal conductivity is a prerequisite for designing Mg-Al alloys with high thermal ***,databases for predicting temperature-and composition-dependent thermal conductivities must be *** this study,Mg-Al-La alloys with different contents of Al2La,Al3La,and Al11La3phases and solid solubility of Al in the α-Mg phase were *** influence of the second phase(s) and Al solid solubility on thermal conductivity was *** results revealed a second phase transformation from Al_(2)La to Al_(3)La and further to Al_(11)La_(3)with the increasing Al content at a constant La *** degree of the negative effect of the second phase(s) on thermal diffusivity followed the sequence of Al2La>Al3La>Al_(11)La_(3).Compared with the second phase,an increase in the solid solubility of Al in α-Mg remarkably reduced the thermal *** the basis of the experimental data,a database of the reciprocal thermal diffusivity of the Mg-Al-La system was established by calculation of the phase diagram (CALPHAD)*** a standard error of±1.2 W/(m·K),the predicted results were in good agreement with the experimental *** established database can be used to design Mg-Al alloys with high thermal conductivity and provide valuable guidance for expanding their application prospects.

关键词： magnesium alloy thermal conductivity thermodynamic calculations materials computation

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Gibberellin promotes cambium reestablishment during secondary vascular tissue regeneration after girdling in an auxin-dependent manner in Populus

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Journal of Integrative Plant Biology 2024年第1期66卷 86-102页

作者： yufei zhang Lingyan Wang Yuexin Wu Donghui Wang Xin‐Qiang He State Key Laboratory of Protein and Plant Gene Research School of Life SciencesPeking UniversityBeijing 100871China

Secondary vascular tissue(SVT)development and regeneration are regulated by *** this study,we used an in vitro SVT regeneration system to demonstrate that gibberellin(GA)treatment significantly promotes auxin-induced cambium *** GA content by overexpressing or knocking down ent-kaurene synthase(KS)affected secondary growth and SVT regeneration in *** poplar DELLA gene GIBBERELLIC ACID INSENSITIVE(PtoGAI)is expressed in a specific pattern during secondary growth and cambium regeneration after *** of PtoGAI disrupted poplar growth and inhibited cambium regeneration,and the inhibition of cambium regeneration could be partially restored by GA *** analysis of the PtaDR5:GUS transgenic plants,the localization of PIN-FORMED 1(PIN1)and the expression of auxin-related genes found that an additional GA treatment could enhance the auxin response as well as the expression of PIN1,which mediates auxin transport during SVT *** together,these findings suggest that GA promotes cambium regeneration by stimulating auxin signal transduction.

关键词： auxin cambium gibberellin Populus secondary vascular tissue regeneration

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Heterogeneous information phase space reconstruction and stability prediction of filling body–surrounding rock combination

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1500-1511页

作者： Dapeng Chen Shenghua Yin Weiguo Long Rongfu Yan yufei zhang Zepeng Yan Leiming Wang Wei Chen School of Civil and Resources Engineering University of Science and Technology of BeijingBeijing 100083China Production Technology Department Longshou MineJinchuan Group Co.Ltd.Jinchang 737100China School of Civil Engineering and Architecture East China Jiaotong UniversityNanchang 330013China

Traditional research believes that the filling body can effectively control stress concentration while ignoring the problems of unknown stability and the complex and changeable stress distribution of the filling body–surrounding rock combination under high-stress *** monitoring data processing methods cannot fully consider the complexity of monitoring objects,the diversity of monitoring methods,and the dynamics of monitoring *** solve this problem,this paper proposes a phase space reconstruction and stability prediction method to process heterogeneous information of backfill–surrounding rock *** three-dimensional monitoring system of a large-area filling body–surrounding rock combination in Longshou Mine was constructed by using drilling stress,multipoint displacement meter,and *** information,such as the stress and displacement of the filling body–surrounding rock combination,was continuously *** with the average mutual information method and the false nearest neighbor point method,the phase space of the heterogeneous information of the filling body–surrounding rock combination was then *** this paper,the distance between the phase point and its nearest point was used as the index evaluation distance to evaluate the stability of the filling body–surrounding rock *** evaluated distances(ED)revealed a high sensitivity to the stability of the filling body–surrounding rock *** new method was then applied to calculate the time series of historically ED for 12 measuring points located at Longshou *** moments of mutation in these time series were at least 3 months ahead of the roadway return *** the ED prediction experiments,the autoregressive integrated moving average model showed a higher prediction accuracy than the deep learning models(long short-term memory and Transformer).Furthermore,the root-mean-square error distribution of the prediction results peaked at 0

关键词： deep mining filling body–surrounding rock combination phase space reconstruction multiple time series stability prediction

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Carbon dots confined nanosheets assembled NiCO_(2)S_(4)@CDs cross-stacked architecture for enhanced sodium ion storage

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Chinese Chemical Letters 2024年第7期35卷 508-513页

作者： Binyang Qin Mengqi Wang Shimei Wu Yining Li Chilin Liu yufei zhang Haosen Fan School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou 510006China

Na^(+)batteries(SIBs)have been emerging as the most promising candidate for the next generation of secondary ***,the development of high-performance and cost-effective anode materials is urgently needed for the large-scale applications of *** this study,carbon dots confined bimetallic sulfide(NiCO_(2)S_(4))architecture(NiCO_(2)S_(4)@CDs)was proposed and synthesized from assembling nanosheets into cross-stacked superstructure and the subsequent confinement of carbon *** novel decussated structure assembly from nanosheets is greatly beneficial to the structure stability of electrode material during the successive charge/discharge ***,the CDs based carbon conductive network can enhance the electrical conductivity for facilitating the easy transport of electron/Na^(+).Benefitting from these advantages,NiCO_(2)S_(4)@CDs exhibits high-rate performance and an ultralong cycling life in ***,the specific capacity of NiCO_(2)S_(4)@CDs can reach the discharge specific capacity as high as 568.9 mAh/g at 0.5 A/g,which can also maintain 302.7 m Ah/g after 750 cycles at 5.0 A/***,ex-situ characterization techniques such as ex-situ XRD and ex-situ XPS were employed to further explore the sodium storage mechanism of the NiCO_(2)S_(4)@CDs anode.

关键词： Carbon dots Sodium ion batteries NiCo_(2)S_(4)@CDs Cross-stacked architecture Ex-situ XRD and XPS

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Regulating the electronic structure of Ir single atoms by ZrO_(2)nanoparticles for enhanced catalytic oxidation of formaldehyde at room temperature

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Chinese Chemical Letters 2024年第7期35卷 200-205页

作者： Shiqi Peng Yongfang Rao Tan Li yufei zhang Jun-ji Cao Shuncheng Lee Yu Huang Key Laboratory of Aerosol Chemistry&Physics State Key Laboratory of Loess and Quaternary Geology(SKLLQG)Institute of Earth EnvironmentChinese Academy of Sciences(CAS)Xi’an 710061China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049China Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Chemical Engineering Kunming University of Science and TechnologyKunming 650500China School of Environment and Energy South China University of TechnologyGuangzhou 51006China School of Environmental and Municipal Engineering Xi’an University of Architecture and TechnologyXi’an 710055China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100190China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong KongChina CAS Center for Excellence in Quaternary Science and Global Change Xi’an 710061China

Developing low-loading single-atom catalysts with superior catalytic activity and selectivity in formaldehyde(HCHO)oxidation at room temperature remains ***,ZrO_(2)nanoparticles coupled low-loading Ir single atoms in N-doped carbon(Ir_(1)-N-C/ZrO_(2))was *** optimal Ir_(1)-N-C/ZrO_(2)with 0.25 wt%Ir loading delivers the high HCHO removal and conversion efficiency(>95%)at 20℃,which is higher than that over Ir_(1)-N-C with the same Ir *** specific rate can reach 1285.6 mmol gIr^(-1)h^(-1),surpassing the Ir based catalysts reported to *** functional theory calculation results and electron spin resonance spectra indicate that the introduction of Zr O_(2)nanoparticles modulate the electronic structure of the Ir single atoms,promoting O_(2)activation to·O_(2)^(–).Moreover,the Ir-C-Zr channel is favorable for the dissociation of·O_(2)^(–)to active oxygen atom(*O),and further accelerates the transformation of HCHO and intermediates(dioxymethylene and formates)to CO_(2)and H_(2)*** work provides a facile strategy to design low-loading single-atom catalysts with high catalytic activity toward HCHO oxidation.

关键词： ZrO_(2)nanoparticles Ir single atoms Electronic structure Formaldehyde Catalytic oxidation

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Regulation of different light conditions for efficient biomass production and protein accumulation of Spirulina platensis

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Journal of Oceanology and Limnology 2024年第1期42卷 174-186页

作者： yufei zhang Xianjun LI Yuhui LI Shiqi LIU Yanrui CHEN Miao JIA Xin WANG Lu zhang Qiping GAO Liang zhang Daoyong YU Baosheng GE State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology China University of Petroleum(East China)Qingdao 266580China Tongwei Co. Ltd.Healthy Aquaculture Key Laboratory of Sichuan ProvinceChengdu 610093China

Light plays an important role in the photosynthesis and metabolic process of ***,how different light conditions regulate the biomass production and protein accumulation of microalgae is mostly *** this study,the influence of different light conditions,including light colors,densities,and light:dark cycles on the cell growth and biochemical composition of Spirulina platensis was symmetrically *** different colored lights,*** all shows an increase trend within the increased light intensity ranges;however,each showing different optimal light *** the same light intensity,different colored lights show different growth rate of *** following the sequence of red>white>green>yellow>*** maximum growth rate and protein accumulation were determined as 21.88 and 5.10 mg/(L·d)when illuminated under red *** energy efficiency of different light sources was calculated and ranked as red>white>blue≈green>*** analysis suggests that red light can promote cell growth and protein accumulation by upregulating genes related to photosynthesis,carbon fixation,and C-N metabolism *** study provides a conducive and efficient way to promote biomass production and protein accumulation of *** by regulating light conditions.

关键词： microalgae light emitting diode protein accumulation biomass production transcriptomic analysis

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基于SBG_XGBoost的煤矿安全应急物资储备中心选址研究

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煤炭学报 2024年第8期49卷 3535-3545页

作者：刘战豫张宇飞河南理工大学工商管理学院能源经济研究中心河南焦作454000 太行发展研究院河南焦作454000

煤矿安全应急物资储备中心选址优化是推动煤矿安全应急体系建设的重要基础,为提高煤矿安全应急物资储备中心选址的准确度和合理性,提出利用人口因素、交通因素、经济因素和自然因素,建立融合多源空间数据的煤矿安全应急物资储备中心选... 详细信息

煤矿安全应急物资储备中心选址优化是推动煤矿安全应急体系建设的重要基础,为提高煤矿安全应急物资储备中心选址的准确度和合理性,提出利用人口因素、交通因素、经济因素和自然因素,建立融合多源空间数据的煤矿安全应急物资储备中心选址机器学习组合模型,提高煤矿安全应急物资储备中心选址的准确度和科学性。利用ArcGIS分别通过渔网划分、空间链接和投影等任务对多源空间数据进行处理,并利用SMOTEENN算法避免数据不均衡的负面影响,从而构建适用于机器学习模型分析的数据集。通过对不同机器学习算法、不同特征选择方法以及不同参数寻优方法进行比较分析,得出XGBoost机器学习算法、Boruta算法和遗传算法在对煤矿安全应急物资储备中心选址分析中,相较于其他机器学习算法、特征选择方法和参数寻优方法其表现更为优异。故基于各自优势,得到煤矿安全应急物资储备中心选址的机器学习组合模型。最后引入SHAP分析方法,对不同特征影响程度、影响方向等进行分析,定量评估输入数据在决策中的贡献,增强模型可解释性。研究结果表明煤矿安全应急物资储备中心选址组合模型性能优异,准确率、精确率、召回率、F1和AUC分别为0.976、0.966、0.989、0.977、0.996,可为选址决策提供有力支持,模型可解释分析也能够为煤矿安全应急物资储备中心选址提供科学参考。

关键词：煤矿安全应急物资储备中心选址机器学习特征选择

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