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Particuology 2024年第7期90卷 292-306页

作者： Chengzhi li Yu zhang Jiahe Shen Wei zhang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China School of Transportation and Logistics Engineering Wuhan University of TechnologyWuhan 430063China Centre for Bulk Solids and Particulate Technologies The University of NewcastleCallaghan NSW 2308Australia

A resolved CFD-DEM method is proposed to simulate the fluid-particle interaction for large complex *** airflow in a vertical sinter fixed bed is numerically studied using this *** multi-sphere clumped method is used to create irregular sinter particles in *** immersed boundary method and dynamic cell refinement are applied to describe the fluid flow around particles with higher resolution,by which the fluid-particle interaction can be simulated more *** simulation results presented the packing voidage distributions and the airflow fields in the sinter beds of different single and mixed particle size *** bed pressure drops were simulated and the results were compared with the corresponding experimental *** good agreement indicated that the proposed resolved CFD-DEM method is an effective tool to model the fluid-particle interaction for irregular large granules in the gas-solid multi-phase systems.

关键词： Resolved CFD-DEM method Irregular sinter particles Multi-sphere clumped method Immersed boundary method Dynamic cell refinement

A Possible γ-Ray Pulsation from PSR J1740-5340B in the Globular Cluster NGC 6397

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Research in Astronomy and Astrophysics 2024年第1期24卷 285-291页

作者： Jiao Zheng Pengfei zhang li zhang Department of Astronomy School of Physics and AstronomyKey Laboratory of Astroparticle Physics of Yunnan ProvinceYunnan UniversityKunming 650091China

Recently, a new radio millisecond pulsar(MSP) J1740-5340B, hosted in the globular cluster(GC) NGC 6397,was reported with a 5.78 ms spin period in an eclipsing binary system with a 1.97 days orbital period. Based on a modified radio ephemeris updated by tool tempo2, we analyze the ~15 yr γ-ray data obtained from the Large Area Telescope on board the Fermi Gamma-ray Space Telescope and detect PSR J1740-5340B's γ-ray pulsation at a confidence level of ~4σ with a weighted H-test value of ~26. By performing a phase-resolved analysis, the γ-ray luminosity in on-pulse interval of PSR J1740-5340B is L_(γ)~ 3.8 × 10^(33) erg s^(-1) using NGC 6397's distance of 2.48 kpc. And γ-rays from the on-pulse part of PSR J1740-5340B contribute ~90% of the total observed γ-ray emissions from NGC 6397. No significant γ-ray pulsation of another MSP J1740-5340A in the GC is *** that the previous four cases of MSPs in GCs, more data in γ-ray, X-ray, and radio are encouraged to finally confirm the γ-ray emissions from MSP J1740-5340B, especially starving for a precise ephemeris.

关键词： gamma-rays:galaxies (stars:)pulsars:individual(PSR J1740-5340B) (Galaxy:)globular clusters:individual(NGC 6397)

Humic acid-mediated transport of a typical soil passivation remediation product(chloropyromorphite)in saturated porous media

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Journal of Environmental Sciences 2024年第7期141卷 51-62页

作者： Xinying li Mengjia zhang Siyuan li Wei Wei School of Environment Jiangsu Engineering Lab of Water and Soil Eco-remediationJiangsu Province Engineering Research Center of Environmental Risk Prevention and Emergency Response TechnologyNanjing Normal UniversityNanjing 210023China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Conversion of labile Pb species into chloropyromorphite(CPY)using phosphorus-bearing amendments was considered to be an ideal strategy in soil passivation ***,the fate and transport of CPY in the soil are poorly *** study aims to fill the knowledge gap by evaluating the fate and transport of CPY under environmentally relevant conditions of humic acid(HA),pH,electrolyte concentration,and species through the saturated sandy *** showed that bare CPY colloids are basically immobile in sandy porous media while the co-existence of HA made the transport of CPY improved by30%-93.5%.Facilitated transport of CPY was attributed to the increased stability of CPY and the repulsive interaction between CPY particles and sands due to HA *** mobility of CPY was also increased with increasing pH from 5.0 to *** the pH was 9 with a10 mmol/L NaCl background solution,the stronger energy barrier between CPY and sand led to enhanced transport *** divalent Ca^(2+)had a more dramatic effect than monovalent Na^(+)on the aggregation and sedimentation of CPY colloids due to its effectivescreening of the surface charge of CPY and bridging interaction with CPY ***-LandauVerwey-Overbeek theory and attachment efficiency calculation indicated that high energy barriers were responsible for the high mobility of CPY colloids,while the retention of CPY in sands was mainly caused by secondary energy minimum and physically *** findings of this work can help to evaluate the fate of soil passivation remediation products in natural water and soil.

关键词： Chloropyromorphite DLVO theory Stability Saturated porous medium Transport

Design optimization of a hexapod vibration isolation system for electro-optical payload

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Chinese Journal of Aeronautics 2024年第2期37卷 330-342页

作者： Jing li Weipeng li Xiaoyan zhang Hai HUANG School of Astronautics Beihang UniversityBeijing 100191China

The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and *** vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting in image blurring and loss of tracking *** this paper,a Hexapod Vibration Isolation System(HVIS)is proposed and optimized to solve this *** optimization aims to centralize and minimize the natural frequencies of HVIS,for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency *** that the design space for HVIS is limited and interfered with the frames of the mobile platform,a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal *** optimization result shows that the natural frequency bandwidth has been reduced by 42.9%,and the maximum natural frequency is reduced by 30.2%.The prototypes of initial and optimal designs are manufactured and *** simulated and experimental results demonstrate the validity of the optimization,and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design.

关键词： Electro-optical payload Vibrations Isolation system Hexapod Optimization Non-collision design

Spatial evolution and spatial production of traditional villages from "backward poverty villages" to "ecologically well-off villages": Experiences from the hinterland of national nature reserves in China

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Journal of Mountain Science 2024年第4期21卷 1100-1118页

作者： zhang Yiyi li Yangbing College of Geography and Environmental Sciences Guizhou Normal UniversityGuiyang 550001China

With the rapid urbanization process,the space of traditional villages in China is undergoing significant *** the spatial evolution of traditional villages is significant in promoting rural spatial transformation and realizing rural revitalization and sustainable rural *** on the traceability analysis of spatial production theory,this paper constructed an analytical framework for the spatial production evolution of traditional villages,analyzed the spatial evolution process and characteristics of traditional villages by using buffer analysis,spatial syntax,and other research methods,and revealed the characteristics of the spatial production evolution of traditional villages and the driving *** results show that:(1)The village spatial formation and development follow the village life cycle theory and usually develop from embryonic villages to diversified and integrated villages;(2)The evolution of village spatial production is characterized by the diversity of material space,the sublimation of daily life space,and the integration of social system space and generalization of emotional space;(3)The evolution of village spatial production from backward and poor village to ecologically well-off village is influenced by a combination of factors;(4)The village has formed a spatial structure of"people-land-scape-culture-industry",realized comprehensive reconstruction and spatial *** study results reflect the spatial evolution characteristics of traditional villages in mountainous areas in a more comprehensive way,which helps to promote the protection and development of traditional villages in mountainous areas and,to a certain extent,provides a reference for the development of rural revitalization.

关键词： Traditional villages Spatial production Spatial evolution Spatial reconstruction

Unveiling three-dimensional sea surface signatures caused by internal solitary waves:insights from the surface water ocean topography mission

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Journal of Oceanology and limnology 2024年第3期42卷 709-714页

作者： Xudong zhang Xiaofeng li Key Laboratory of Ocean Observation and Forecasting Key Laboratory of Ocean Circulation and WavesInstitute of OceanologyChinese Academy of SciencesQingdao 266071China

Internal solitary waves(ISW),characterized by large amplitude and long propagation distance,are widespread in global *** remote sensing images have played an essential role in studying ISWs,they mainly exploit two-dimensional image ***,with the launch of the surface water ocean topography(SWOT)satellite on December 16,2022,a unique opportunity has emerged to capture wide-swath three-dimensional ISW-induced sea surface *** this study,we examine ISWs in the Andaman Sea using data from the Ka-band Radar Interferometer(KaRIN),a crucial sensor onboard *** not only provides backscattering satellite images but also employs synthetic aperture interferometry techniques to retrieve wide-swath two-dimensional sea surface height *** observations in the Andaman Sea revealed the presence of ISWs characterized by dark-bright strips and surface elevation *** surface soliton has an amplitude of 0.32 m,resulting in an estimation of ISW amplitude of approximately 60 *** contrast to traditional two-dimensional satellite images or nadir-looking altimetry data,the SWOT mission’s capability to capture threedimensional sea surface information represents a significant *** breakthrough holds substantial promise for ISW studies,particularly in the context of ISW amplitude inversion.

关键词： internal solitary wave(ISW) surface water ocean topography(SWOT) altimeter

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research(International) 2024年第2期31卷 318-328页

作者： Le-le Niu Zheng-jian liu Jian-liang zhang Yao-zu Wang Zhen-xing Yang Si-da li Chang-dong Shan Ben Feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

On limit fractional Volterra hierarchies

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Communications in Theoretical Physics 2024年第1期76卷 7-16页

作者： lixiang zhang Chuanzhong li School of Mathematics and Statistics Ningbo UniversityNingbo315211China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao266590China

For the limit fractional Volterra(LFV)hierarchy,we construct the n-fold darboux transformation and the soliton ***,we extend the LFV hierarchy to the noncommutative LFV(NCLFV)hierarchy,and construct the darboux transformation expressed by quasi determinant of the noncommutative ***,we establish the relationship between new and old solutions of the NCLFV ***,the quasi determinant solutions of the NCLFV hierarchy are obtained.

关键词： limit fractional Volterra hierarchy noncommutative limit fractional Volterra hierarchy darboux transformation soliton solution quasi determinant solution

Optimal Operation with Dynamic Partitioning Strategy for Centralized Shared Energy Storage Station with Integration of Large-scale Renewable Energy

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 359-370页

作者： Jianlin li Zhijin Fang Qian Wang Mengyuan zhang Yaxin li Weijun zhang Beijing Future Technology Innovation Centre for Electrochemical Energy Storage System Integration North China University of Technology Beijing China State Grid Fujian Electric Power Research Institute Fuzhou China

As renewable energy continues to be integrated into the grid,energy storage has become a vital technique supporting power system *** effectively promote the efficiency and economics of energy storage,centralized shared energy storage(SES)station with multiple energy storage batteries is developed to enable energy trading among a group of *** this paper,we propose the optimal operation with dynamic partitioning strategy for the centralized SES station,considering the day-ahead demands of large-scale renewable energy power *** implement a multi-entity cooperative optimization operation model based on Nash bargaining *** model is decomposed into two subproblems:the operation profit maximization problem with energy trading and the leasing payment bargaining *** distributed alternating direction multiplier method(ADMM)is employed to address the subproblems *** reveal that the optimal operation with a dynamic partitioning strategy improves the tracking of planned output of renewable energy entities,enhances the actual utilization rate of energy storage,and increases the profits of each participating *** results confirm the practicality and effectiveness of the strategy.

关键词： Shared energy storage(SES) dynamic partitioning strategy optimal operation Nash bargaining theory actual utilization rate of energy storage

Engineering oxygen vacancies on Tb-doped ceria supported Pt catalyst for hydrogen production through steam reforming of long-chain hydrocarbon fuels

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Chinese Journal of Chemical Engineering 2024年第4期68卷 181-192页

作者： Zhourong Xiao Changxuan zhang Peng li Desong Wang Xiangwen zhang li Wang Jijun Zou Guozhu li State Key Laboratory of Metastable Materials Science and Technology(MMST) Hebei Key Laboratory of Applied ChemistryCollege of Environmental and Chemical EngineeringYanshan UniversityQinhuangdao 066004China Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Steam reforming of long-chain hydrocarbon fuels for hydrogen production has received great attention for thermal management of the hypersonic vehicle and fuel-cell *** this work,Pt catalysts supported on CeO_(2)and Tb-doped CeO_(2)were prepared by a precipitation *** physical structure and chemical properties of the as-prepared catalysts were characterized by powder X-ray diffraction,scanning electron microscopy,transmission electron microscopy,Raman spectroscopy,H_(2)temperature programmed reduction,and X-ray photoelectron *** results show that Tb-doped CeO_(2)supported Pt possesses abundant surface oxygen vacancies,good inhibition of ceria sintering,and strong metal-support interaction compared with CeO_(2)supported *** catalytic performance of hydrogen production via steam reforming of long-chain hydrocarbon fuels(n-dodecane)was *** with 2Pt/CeO_(2),2Pt/Ce_(0.9)Tb_(0.1)O_(2),and 2Pt/Ce_(0.5)Tb_(0.5)O_(2),the 2Pt/Ce_(0.7)Tb_(0.3)O_(2)has higher activity and stability for hydrogen production,on which the conversion of n-dodecane was maintained at about 53.2%after 600 min reaction under 700℃at liquid space velocity of 9 ml·g^(-1)·h^(-1).2Pt/CeO_(2)rapidly deactivated,the conversion of n-dodecane was reduced to only 41.6%after 600 min.

关键词： Steam reforming n-Dodecane Hydrogen production Pt-based catalyst Oxygen vacancy CeO_(2)