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Multi-field Coupled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan Xuhui Lou Yujun Chen Zhihong Zhou Qingyuan wang lianhua Ma Xiaobao Tian Non-Destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller Co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial Technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the complex multi-field coupling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous concentration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that contribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric components.

关键词： Ferroelectrics Multi-field coupling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect

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陕西畜牧业节水养殖现状及建议

畜牧兽医杂志 2024年第2期43卷 68-71页

作者：王莲花王新慧周旭东胡张涛沈新元雷艳胡建宏陕西省现代农业科学研究院陕西西安710000 西北农林科技大学

陕西省是畜牧养殖大省,畜牧养殖对该省的农民脱贫致富和经济增长起到重要的推动作用。近年来,随着畜牧养殖规模化、集约化发展,水资源短缺已成为制约畜牧业可持续发展的瓶颈问题。畜牧节水技术的推广实施是解决这一难题的重要举措,能进... 详细信息

陕西省是畜牧养殖大省,畜牧养殖对该省的农民脱贫致富和经济增长起到重要的推动作用。近年来,随着畜牧养殖规模化、集约化发展,水资源短缺已成为制约畜牧业可持续发展的瓶颈问题。畜牧节水技术的推广实施是解决这一难题的重要举措,能进一步发掘畜牧养殖业的节水潜力,进而推动畜牧业现代化发展,助理力乡村战略实施。本文主要介绍了陕西省畜牧业发展现状、畜牧节水方面存在的问题及相关畜牧节水技术,并对畜牧节水的推广提出几点建议。希望能让更多的人了解畜牧节水,关注畜牧节水,践行畜牧节水。

关键词：陕西省畜牧业节水养殖节水技术

Research on Refined Oil Distribution Plan Based on Dynamic Time Window

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Journal of Applied Mathematics and Physics 2017年第11期5卷 2104-2111页

作者： Qian Liu lianhua wang Le Yu Beijing Wuzi University Beijing China

Based on the analysis of the refined oil distribution plan which includes the various vehicles models-single oil-multiple gas stations. This paper puts forward the dynamic time window of oil supplementation based on every moment, and establishes the mathematical model of the refined oil distribution plan, using C language, taking various circumstances of the model into account to find the optimal solution through several operations. This process can make the refined oil distribution plan and the distribution route is more reasonable. At the same time, the distribution cost is lowest. Through the analysis of the experimental results, the validity and algorithm of the model are proved.

关键词： Refined Oil Distribution Vehicle Scheduling Problem Time Window Optimized Model

Analyzing Collaborative Development of E-Commerce and Logistics Based on DEA

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Open Journal of Modelling and Simulation 2017年第2期5卷 158-167页

作者： lianhua wang Wei Qi Shi Hui School of Information Beijing Wuzi University Beijing China

In order to know the current collaborative development situation and relationship of E-commerce and logistics, the paper evaluates the whole collaborative development level of Chinese E-commerce and logistics from 2008 to 2014 using the DEA model. Fund, infrastructure, labor and collaborative development are evaluated and analyzed in this model. The research indicates that E-commerce facilitates the logistics development but logistics can’t support E-commerce development well due to the lag effect which leads to lower collaborative development level. So optimizing the ratio of logistics investment and output, promoting logistics service quality and accelerating logistics development have been the key factors for promoting the collaborative development of E-commerce and logistics.

关键词： E-Commerce Logistics EDA Model Collaborative Development Assessment

Time-History Dynamic Characteristics of Reinforced Soil-Retaining Walls

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Structural Durability & Health Monitoring 2024年第6期18卷 853-869页

作者： lianhua Ma Min Huang Linfeng Han Department of Building and Environmental Safety Chongqing Vocational Institute of Safety&TechnologyChongqing404120China National Engineering Research Center for Inland Waterway Regulation Chongqing Jiaotong UniversityChongqing400074China

Given the complexities of reinforced soil materials’constitutive relationships,this paper compares reinforced soil composite materials to a sliding structure between steel bars and soil and proposes a reinforced soil constitutive model that takes this sliding into account.A finite element dynamic time history calculation software for composite response analysis was created using the Fortran programming language,and time history analysis was performed on reinforced soil retaining walls and gravity retaining *** vibration time histories of reinforced soil retaining walls and gravity retaining walls were computed,and the dynamic reactions of the two types of retaining walls to vibration were compared and *** dynamic performance of reinforced earth retaining walls was evaluated.

关键词： Reinforced earth retaining walls time history dynamic analysis finite element

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新媒体时代大学生媒介素养问题思考

上海师范大学学报（哲学社会科学版） 2012年第3期41卷 108-116页

作者：王莲华上海师范大学校办上海200234

新媒体具有交互性、即时性、海量性、共享性、多媒体等特征。正是由于新媒体的这些技术特征,赋予了媒介素养更加明显的时代性,它既指人们面对新媒体各种信息时的选择能力、理解能力、质疑能力、评估能力、创造和制作能力、思辩的反应能... 详细信息

新媒体具有交互性、即时性、海量性、共享性、多媒体等特征。正是由于新媒体的这些技术特征,赋予了媒介素养更加明显的时代性,它既指人们面对新媒体各种信息时的选择能力、理解能力、质疑能力、评估能力、创造和制作能力、思辩的反应能力,又指使媒介信息为个人生活、社会发展所用的能力。当代大学生在媒介接触消费、媒介认知理解、媒介应用制作等方面,能够比较好地适应新媒体环境,但从其具体行为看,也存在对媒介的批判能力较弱、对媒介的使用不够深入,以及网络道德和法律意识比较薄弱等问题。这些问题的产生和存在,既有客观原因,也有主观原因。媒介素养是公民素质的基本内容,作为公民素质教育的一个重要部分,媒介素养教育以跨学科的综合要求培养既有科学素养,又有人文素养的全面发展人才,促进大学生思想道德素质、科学文化素质协调发展。为此,要积极探索培育和提升大学生媒介素养的路径方法。

关键词：新媒体大学生媒介素养问题与思考

Old Pinus massoniana forests benefit more from recent rapid warming in humid subtropical areas of central-southern China

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Journal of Forestry Research 2024年第5期35卷 155-170页

作者： Wenxin Li Liangjun Zhu lianhua Zhu Mengdan Jing Censhi Qian Yu Zhu Paolo Cherubini College of Life Science and Technology Central South University of Forestry and TechnologyChangsha 410004People’s Republic of China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Department of Forest and Conservation Sciences Faculty of ForestryUniversity of British Columbia2004-2424 Main MallVancouverBC V6T 1Z4Canada

Trees progress through various growth stages,each marked by specific responses and adaptation strate-gies to environmental *** the importance of age-related growth responses on overall forest health and management policies,limited knowledge exists regarding age-related effects on dendroclimatic relationships in key subtropical tree *** this study,we employed a den-drochronological method to examine the impact of rapid warming on growth dynamics and climatic sensitivity of young(40–60 years)and old(100–180 years)Pinus mas-soniana forests across six sites in central-southern *** normalized log basal area increment of trees in both age groups increased significantly following rapid warming in *** in young forests further showed a distinct growth decline during a prolonged severe drought(2004–2013),whereas those in old forests maintained growth *** growth was more strongly influenced by temperature than by moisture,particularly in old *** tem-peratures strongly and positively impacted the growth of old trees but had a weaker effect on young *** forests had a significantly lower resistance to extreme drought but faster recovery compared to young ***“divergence problem”was more pronounced in younger forests due to their heightened sensitivity to warming-induced drought and heat *** ongoing warming,young forests also may initially experience a growth decline due to their heightened sensitivity to winter *** findings underscore the importance of considering age-dependent changes in forest/tree growth response to warming in subtropical forest man-agement,particularly in the context of achieving“Carbon Peak&Carbon Neutrality”goals in China.

关键词： Tree rings Pinus massoniana Age effects Drought resilience Subtropical forests Rapid warming

Cu-Zn isotope compositions of hydrothermal sediments from the southern Mid-Atlantic Ridge:implications to the sediment formation and mineral exploration

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Journal of Oceanology and Limnology 2024年第5期42卷 1470-1485页

作者： Baoju YANG lianhua HE Chuanshun LI Qiannan HU Bingfu JIN Jihua LIU School of Resources and Environmental Engineering Ludong UniversityYantai 264025China Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China

Six hydrothermal sediment samples were collected from the Xunmei and Tongguan hydrothermal fields along the southern Mid-Atlantic Ridge during the China Ocean Cruise DY46 in *** and oxides in the samples were separated,and Cu and Zn isotope compositions were *** show that the ranges ofδ^(65)Cu values of the bulk sediments,sulfides,and oxides were 0.36‰-2.46‰,-0.21‰-1.10‰,and 0.68‰-1.52‰,***δ^(65)Cu values of sulfides in four samples(46II-14,46II-30,46III-06,and 46II-09)were relatively low(-0.21‰-0.50‰),corresponding to theδ^(65)Cu values of sulfides from inactive old hydrothermal chimneys in northern Mid-Atlantic Ridge(n MAR),suggesting that the sulfides in the sediments were originated from collapsed dead chimney *** theδ^(65)Cu values of the other two samples(46III-02 and 46III-08)were relatively high(1.10‰-0.96‰),corresponding to theδ^(65)Cu values for active hydrothermal chimneys sulfides in n MAR,which indicated that the sulfides in these two samples might mainly come from sulfide particles settled from active hydrothermal *** of the high density of sulfide particles,they tended to settle near the hydrothermal vents ***,highδ^(65)Cu values of sulfides in 46III-02 and 46III-08 implied that undiscovered active hydrothermal vents near the sampling positions of 46III-02 in the Xunmei hydrothermal field and 46III-08 in the Tongguan hydrothermal ***δ^(66)Zn values of hydrothermal sediments and sulfides ranged 0.11‰-0.43‰and 0.29‰-0.67‰,*** the four samples from the Xunmei hydrothermal field,a positive correlation was found between the distance of the sampling position from sulfide mineralized spot and the Zn isotopic ratio,showing that the greater the distance from the mineralized spot,the heavier the Zn isotope composition as seen in two samples(46II-30 and 46II-14)of the Xunmei-3 *** result aligned with the findings of Wilkinson et al.(2005)and Baumgartner et al.(2023),sugges

关键词： Cu-Zn isotope hydrothermal sediments mineral exploration southern Mid-Atlantic Ridge

Multi-Scale Design and Optimization of Composite Material Structure for Heavy-Duty Truck Protection Device

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Computer Modeling in Engineering & Sciences 2024年第5期139卷 1961-1980页

作者： Yanhui Zhang lianhua Ma Hailiang Su Jirong Qin Zhining Chen Kaibiao Deng School of Mechanical and Automotive Engineering Guangxi University of Science and TechnologyLiuzhou545006China Commercial Vehicle Technology Center Dongfeng Liuzhou Automobile Co.Ltd.Liuzhou545005China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou510641China

In this paper,to present a lightweight-developed front underrun protection device(FUPD)for heavy-duty trucks,plain weave carbon fiber reinforced plastic(CFRP)is used instead of the original high-strength ***,the mechanical and structural properties of plain carbon fiber composite anti-collision beams are comparatively analyzed from a multi-scale *** studying the design capability of carbon fiber composite materials,we investigate the effects of TC-33 carbon fiber diameter(D),fiber yarn width(W)and height(H),and fiber yarn density(N)on the front underrun protective beam of carbon fiber *** on the investigation,a material-structure matching strategy suitable for the front underrun protective beam of heavy-duty trucks is ***,the composite material structure is optimized by applying size optimization and stack sequence optimization methods to obtain the higher performance carbon fiber composite front underrun protection beam of commercial *** results show that the fiber yarn height(H)has the greatest influence on the protective beam,and theH1matching scheme for the front underrun protective beamwith a carbon fiber composite structure exhibits superior *** proposed method achieves a weight reduction of 55.21% while still meeting regulatory requirements,which demonstrates its remarkable weight reduction effect.

关键词： Structural optimization front underrun protection device carbon fiber reinforced plastic multi-scale model lightweight design