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Review of the bennettitalean genus Weltrichia

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Journal of Palaeogeography 2019年第2期8卷 109-129页

作者： Mihai Emilian Popa Faculty of Geology and Geophysics Department of Geology and Doctoral School of GeologyLaboratory of PalaeontologyUniversity of Bucharest

The bennettitalean male reproductive structure Weltrichia Braun 1849 *** 1969(Family Williamsoniaceae) is discussed from several points of view,including anatomy and morphology,species diversity and validity,phytogeographical and stratigraphical distribution,and reproduction strategy.A very rare fossil,genus Weltrichia includes 25 valid species distributed in both hemispheres during Triassic and Jurassic *** contribution critically reviews the systematics of the entire genus,together with its stratigraphical and palaeophytogeographical significance.

关键词： Bennettitales Weltrichia Male reproductive structure Triassic Jurassic

Synthesis of faveolate open-structured Ru-N/C cathode catalyst with high bifunctional activity for rechargeable quasi-solid-state Li-O_(2)batteries

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Nano Research 2025年第1期18卷 351-361页

作者： Tie Liu school of Chemistry and Chemical Engineering Heze UniversityHeze 274015China

The constituents and geometric design of cathodic electrocatalyst to achieve high activity and durability are effective but challenging for the development of high-performance Li-O_(2)*** study employs a mild solution precipitation method followed by thermolysis to construct a faveolate open-structured Ru-N/C matrix with a loosely braided network morphology as a bifunctional *** details prove that this hybrid structure is composed of ultrafine Ru globular nanoparticles(ca.2 nm)coated with an N-enriched carbon film and exhibits a valuable beehive through-hole character for rapid mass transport during oxygen redox *** synergistic effect of open-structured and reticular network matrix with metal-N4 coordination induces asymmetric charge distributions with moderate adsorption/desorption behaviour with oxygen ***,this particular Ru-N/C matrix cathode provides a promising Li_(2)O_(2)accommodation space and exhibits superior electrochemical performance in terms of a positive discharge plateau and low charge ***,the assembled batteries also present a high discharge capacity and a long cycle life(exceeding 283 cycles).The density functional theory(DFT)calculations also corroborate the assertion that the Ru-N/C catalyst exhibits robust electronic coupling transfer and superior bifunctional *** such,our work demonstrates that this type of open-structured Ru-N/C matrix is promising for fabricating high-performance quasi solid-state Li-O_(2)batteries.

关键词： ruthenium nitride nitrogen-doped carbon electrocatalyst Li-O_(2)battery

Research on the Construction of Agricultural Product Virtual Logistics Enterprise

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Journal of Shanghai Jiaotong university(Science) 2016年第1期21卷 63-68页

作者：刘璠 school of Business Administration Post-doctoral Research Center Zhongnan University of Economics and Law

With the development that the demand for agricultural products' consumer market is gradually toward to the direction of complication, the existing agricultural logistics organizational model cannot adapt to the characteristics of agricultural product logistics and the changes in the consumer demand. According to the analysis of virtual operation trend of agricultural product logistics enterprise, this paper expatiates the concept and characteristics of agricultural product virtual logistics enterprise(APVLE) and proposes four steps to build an APVLE, including the analysis of key elements about APVLE, the identification about agricultural product logistics business, the project decomposition of APVLE and the partner selection in APVLE.

关键词： virtual operation agricultural product virtual logistics enterprise construction

Universal design of three-dimensional porous graphene-iron based promotors for kinetically rationalized lithium-sulfur chemistry

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Journal of Energy Chemistry 2025年第1期100卷 192-200页

作者： Hua Gao Yunfeng Zhang Menglei Wang Ruoxuan Yang Shuai Feng Xuan Cao Yaping Zhang Zhongyuan Lu Yingze Song State Key Laboratory of Environment-Friendly Energy Materials School of Materials and Chemistry Southwest University of Science and Technology school of Material Science and Engineering Henan University of Technology College of Chemistry and Chemical Engineering Taishan University

Lithium-sulfur （Li-S） batteries are widely deemed to be one of the most potential candidates for future secondary batteries because of their remarkable energy ***,notorious polysulfide shuttling and retarded sulfur reaction kinetics pose significant obstacles to the further application of Li-S *** rationally designed highly active electrocatalysts can facilitate polysulfide conversion,the universal and scalable synthesis strategies need to be ***,a universal synthetic strategy to construct a series of three-dimensional （3D） porous graphene-iron （3DGr-Fe） based electrocatalysts involving 3DGr-FeP,3DGr-Fe3C,and 3DGr-Fe3Se4is exploited for manipulating the Li-S redox *** has been observed that the implementation of a 3D porous Gr architecture leads to the well-designed conductive networks,while the uniformly dispersed iron nanoparticles introduce an abundance of active sites,fostering the lithium polysulfide conversion,thereby bolstering the overall electrochemical *** Li-S battery with the 3DGr-Fe based electrocatalyst exhibits remarkable capacity retention of 94.8%upon 100 times at 0.2 ***,the soft-packaged Li-S pouch cell based on such a 3DGr-Fe electrocatalyst delivers superior capacity of 1060.71 mA h g-1and guarantees for the continuous 30 min work of fan *** investigation gives comprehensive insights into the design,synthesis,and mechanism of 3DGr-Fe based electrocatalysts with high activity toward efficient and durable Li-S batteries.

关键词： Lithium-sulfur battery Universal synthesis 3D graphene-iron based promotor Electrocatalysis

Long-term settlement prediction of high-speed railway bridge pile foundation

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Journal of Central South University 2014年第6期21卷 2415-2424页

作者：杨奇冷伍明张升聂如松魏丽敏赵春彦刘维正 school of Civil Engineering Central South University Mobile Post-doctoral Stations of Traffic and Transportation Engineering Central South University

The process and characteristics of loading on high-speed railway bridge pile foundation were firstly obtained by means of field research and analysis,and the corresponding loading function was ***-dimensional consolidation equation of elastic multilayered soils was then established with single drainage or double drainages under multilevel ***,the formulas for calculating effective stress and settlement were derived from the Laplace numerical inversion *** three-dimensional composite analysis method of bridge pile group was improved,where the actual load conditions of pile foundation could be simulated,and the consolidation characteristics of soil layers beneath pile were also taken into ***,a corresponding program named LTPGS was developed to improve the calculation *** comparison between long-term settlement obtained from the proposed method and the in-situ measurements of pile foundation was illustrated,and a close agreement is *** error between computed and measured results is less than 1 mm,and it gradually reduces with *** is shown that the proposed method can effectively simulate the long-term settlement of pile foundation and program LTPGS can provide a reliable estimation.

关键词： bridge pile foundation long-term settlement consolidation Laplace numerical inversion transform multilevel loading multilayered soils

China＇s Engagement with the Sixteen Countries of Central, East and Southeast Europe under the Belt and Road Initiative

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China & World Economy 2017年第5期25卷 101-124页

作者： Anastas Vangeli doctoral Researcher Graduate School for Social Research Polish Academy of Sciences Poland

This paper provides an overview of China＇s burgeoning relationship with Central, Eastand Southeast Europe （CESEE） in the context of the Belt and Road Initiative （BRI）.China has rapidly expanded the extent of its interactions with CESEE since 2012,and this region has subsequently become one of the focal points of the BRI. The keyfeature of China＇s engagement with CESEE is the devising of an experimental andinnovative approach, demonstrated in the establishment of an institutional mechanismfor cooperation with a particular group of16 CESEE countries （16＋1）. The case ofChina-CESEE relations offers an insight into how, in the era of the BRL China iscomplementing its economic approach with institution-building and policy *** article concludes that as the BRI progresses, these tendencies will remain central toChina＇s relations with CESEE.

关键词： Belt and Road Initiative, foreign relations, 16+1

Atomistic simulation of topaz:Structure,defect,and vibrational properties

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Chinese Physics B 2015年第9期24卷 355-361页

作者：牛继南沈晒晒刘章生冯培忠欧雪梅强颖怀朱真才 Post-doctoral Mobile Station of Mechanical Engineering China University of Mining and TechnologyXuzhou school of Materals Science and Engineering China University of Mining and TechnologyXuzhou

The clay force field（CLAYFF） was supplemented by fluorine potential parameters deriving from experimental structures and used to model various topazes. The calculated cell parameters agree well with the observed structures. The quasi-linear correlation of the b lattice parameter to different F/OH ratios calculated by changing fluorine contents in OH-topaz supports that the F content can be measured by an optical method. Hydrogen bond calculations reveal that the hydrogen bond interaction to H1 is stronger than that to H2, and the more fluorine in the structure, the stronger the hydrogen bond interaction of hydroxyl hydrogen. Defect calculations provide the formation energies of all common defects and can be used to judge the ease of formation of them. The calculated vibrational frequencies are fairly consistent with available experimental results, and the 1080-cm^-1frequency often occurring in natural OH-topaz samples can be attributed to Si–F stretching because of the F substitution to OH and the Al–Si exchange.

关键词： topaz modeling lattice defect

Stochastic seismic response of structures with added viscoelastic dampers modeled by fractional derivative

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Earthquake Engineering and Engineering Vibration 2003年第1期2卷 133-140页

作者：叶昆李黎唐家祥 school of Civil Engineering Huazhong University of Science and TechnologyWuhan 430074China Doctoral Candidate school of Civil Engineering Huazhong University of Science and TechnologyWuhan 430074China Professor

Viscoelastic dampers,as spplementary energy dissipation devices,have been used in building structures un- der seismic excitation or wind *** analytical models have been proposed to describe their dynamic force deform- ation *** these analytieal models,the fractional derivative models have attracted more attention as they can capture the frequency dependence of the material stiffness and damping properties observed from tests very *** this paper,a Fourier-transform-based technique is presented to obtain the fractional unit impulse function and the response of structures with added viscoelastic dampers whose foree-detormation relationship is described by a fractional derivative mod- ***,a Duhamel integral-type expression is suggested for the response analysis of a fractional damped dynamie system subjected to deterministic or random *** numerical verification,it is shown that viscoelastic dampers are ef- fective in reducing structural responses over a wide frequency range,and the proposed schmnes can be used to accurately predict the stochastic seismic response of structures with added viscoelastic dampers described by a Kelvin model wills frac- tional derivative.

关键词： fractional derivative viscoelastic damper stochastic seismic response

Rendering algorithms for aberrated human vision simulation

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Visual Computing for Industry,Biomedicine,and Art 2023年第1期6卷 51-75页

作者： István Csoba Roland Kunkli Faculty of Informatics University of DebrecenDebrecen 4028Hungary doctoral school of Informatics University of DebrecenDebrecen 4028Hungary

Vision-simulated imagery―the process of generating images that mimic the human visual system―is a valuable tool with a wide spectrum of possible applications, including visual acuity measurements, personalized planning of corrective lenses and surgeries, vision-correcting displays, vision-related hardware development, and extended reality discomfort reduction. A critical property of human vision is that it is imperfect because of the highly influential wavefront aberrations that vary from person to person. This study provides an overview of the existing computational image generation techniques that properly simulate human vision in the presence of wavefront aberrations. These algorithms typically apply ray tracing with a detailed description of the simulated eye or utilize the point-spread func-tion of the eye to perform convolution on the input image. Based on the description of the vision simulation tech-niques, several of their characteristic features have been evaluated and some potential application areas and research directions have been outlined.

关键词： Human vision Human visual system Vision simulation Wavefront aberrations Visual aberrations Vision-realistic rendering