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Journal of Rare Earths 2024年第8期42卷 1447-1457,I0002页

作者： jiantong wang Changshuai Gong Sihan Yang Qi Zhu Xuejiao wang ji-Guang Li College of Chemistry and Materials Engineering Bohai UniversityJinzhou121007China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China Research Center for Electronic and Optical Materials National Institute for Materials ScienceTsukubaIbaraki 305-0044Japan

Phosphor-converted near-infrared light-emitting diodes(NIR pc-LEDs) are finding applications in various fields including food quality analysis,biomedical imaging,night vision,and *** crucial factor in the development of NIR pc-LEDs devices lies in the advancement of high-performance broadband NIR phosphors,In this work,novel Cr^(3+)-activated silicate phosphors NaRESi_(3)O_(9)(RE=Y,Lu,Sc) are *** silicate has a special 3D network structure in which RE has four different sites,forming four octahedrons and providing suitable occupation sites for Cr^(3+).The phosphors demonstrate a wide emission spectrum ranging from 750 to 1450 nm when excited by light at 468 *** full width at half maximum(FWHM),which benefits from the presence of Cr^(3+)ions occupying multiple sites,is measured to be 203 ***,the strongest emission peak is observed at a longer wavelength of 984 nm compared to most other systems activated by Cr^(3+).The Na_(3)ScSi_(3)O_(9) lattice provides a weak crystal field(Dq/B=1.97) and weak phonon-photon coupling for Cr^(3+),and the integrated emission intensity of Na_(3)ScSi_(3)O_(9):0,03Cr^(3+)is 4.66 times stronger than that of Na_(3)YSi_(3)O_(9):0.03Cr^(3+).

关键词： Rare earths Broadband near-infrared Silicate Photoluminescence Cr^(3+)

Chemical composition evaluation and pyrolysis behavior of biomass tar:Pyrolysis experiment and kinetic studies

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International Journal of Agricultural and Biological Engineering 2024年第3期17卷 230-234页

作者： Weijuan Lan Yunlong zhou jiaxin Liu Yingxian wang Dongxue Yin jiangtao ji Xin jin School of Agricultural Equipment Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina

Biomass gasification process generates the residual tar,which in turn exerts some negative influence on biomass gasification *** reduce this harmful influence,an evaluation of the tar properties during the biomass gasification was *** chemical composition and pyrolysis behavior of biomass tar were *** complex chemical composition of the tar,which includes phenol derivatives,naphthalene derivatives,other macromolecular aromatic compounds,furans,and other compounds(carbon number from 7 to 14),was established by gas chromatography-mass spectrometry *** analysis was performed with two heating rates(10℃/min and 20℃/min),and Coats-Redfern method was applied to assess the kinetic parameters,i.e.,the activation energy(E)and pre-exponential factor(A)of tar thermochemical *** results showed that the main degradation of tar is a two-step process,including a volatilization step at lower temperatures(<105℃)and a pyrolysis step at higher temperatures(105℃-380℃).The application of the Coats-Redfern method revealed a variation trend of the activation energy during the decomposition of tar in a non-isothermal *** shows that high temperature is more conducive to tar *** adjusting the temperature to control the generation and removal of tar,new approaches are provided for designing and optimizing biomass gasification systems.

关键词： biomass tar chemical components thermogravimetric analysis kinetics

Fuzzy-Model-Based Finite Frequency Fault Detection Filtering Design for Two-Dimensional Nonlinear Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2099-2110页

作者： Meng wang Huaicheng Yan jianbin Qiu Wenqiang ji Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationSchool of Information Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Research Institute of Intelligent Control and Systems School of AstronauticsHarbin Institute of TechnologyHarbin 150080China School of Artificial Intelligence Hebei University of TechnologyTianjin 300401China IEEE

This article studies the fault detection filtering design problem for Roesser type two-dimensional(2-D)nonlinear systems described by uncertain 2-D Takagi-Sugeno(T-S)fuzzy ***,fuzzy Lyapunov functions are constructed and the 2-D Fourier transform is exploited,based on which a finite frequency fault detection filtering design method is proposed such that a residual signal is generated with robustness to external disturbances and sensitivity to *** has been shown that the utilization of available frequency spectrum information of faults and disturbances makes the proposed filtering design method more general and less conservative compared with a conventional nonfrequency based filtering design ***,with the proposed evaluation function and its threshold,a novel mixed finite frequency H_(∞)/H_(-)fault detection algorithm is developed,based on which the fault can be immediately detected once the evaluation function exceeds the ***,it is verified with simulation studies that the proposed method is effective and less conservative than conventional non-frequency and/or common Lyapunov function based filtering design methods.

关键词： Fault diagnosis finite frequency specifications mixed H_(∞)/H_(-)performance two-dimensional nonlinear systems

A Pre-Selection-Based Ant Colony System for Integrated Resources Scheduling Problem at Marine Container Terminal

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Computers, Materials & Continua 2024年第8期80卷 2363-2385页

作者： Rong wang Xinxin Xu Zijia wang Fei ji Nankun Mu School of Electronic and Information Engineering South China University of TechnologyGuangzhou510641China School of Computer Science and Technology Ocean University of ChinaQingdao266100China School of Computer Science and Cyber Engineering Guangzhou UniversityGuangzhou510006China School of Computer Science Chongqing UniversityChongqing400044China

Marine container terminal(MCT)plays a key role in the marine intelligent transportation system and international logistics ***,the efficiency of resource scheduling significantly influences the operation performance of *** solve the practical resource scheduling problem(RSP)in MCT efficiently,this paper has contributions to both the problem model and the algorithm ***,in the problem model,different from most of the existing studies that only consider scheduling part of the resources in MCT,we propose a unified mathematical model for formulating an integrated *** new integrated RSP model allocates and schedules multiple MCT resources simultaneously by taking the total cost minimization as the ***,in the algorithm design,a pre-selection-based ant colony system(PACS)approach is proposed based on graphic structure solution representation and a pre-selection *** the one hand,as the RSP can be formulated as the shortest path problem on the directed complete graph,the graphic structure is proposed to represent the solution encoding to consider multiple constraints and multiple factors of the RSP,which effectively avoids the generation of infeasible *** the other hand,the pre-selection strategy aims to reduce the computational burden of PACS and to fast obtain a higher-quality *** evaluate the performance of the proposed novel PACS in solving the new integrated RSP model,a set of test cases with different sizes is *** results and comparisons show the effectiveness and efficiency of the PACS algorithm,which can significantly outperform other state-of-the-art algorithms.

关键词： Resource scheduling problem(RSP) ant colony system(ACS) marine container terminal(MCT) pre-selection strategy

Solid solution strategy modulated defects engineering of(Cr_(1-x)V_(x))_(2)AlC MAX phase toward superior electromagnetic wave absorption

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Rare Metals 2024年第7期43卷 3205-3219页

作者： ji-Lin Gou Yu-Kai Chang Shu Liu Peng-Hui Li Ping-Hao Cui Qian-Ku Hu Li-Bo wang Xin Zhang Jun-Kai wang Qi-Xun Xia Ai-Guo zhou School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454003China Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

Defects engineering is an effective strategy for manipulating electromagnetic parameters and enhancing electromagnetic wave(EMW)absorption ***,the relationship between them is not clear,especially in solid solution *** this work,a series of(Cr_(1-x)V_(x))_(2)AlC MAX phase solid solutions with layered structure were prepared via tuning the ratio of Cr and V to explore their EMW absorption *** experimental results indicated that the doping of V atoms at the M-site could effectively regulate its impedance matching and EMW absorption properties by introducing appropriate numbers of defects in the crystal,such as twin boundaries,dislocations and lattice *** them,if Cr:V=3:1,Cr_(1.5)V_(0.5)AlC,as radar absorption materials,could reach a strong reflection loss of-51.8 dB at the frequency of 12.8 GHz under an ultra-thin thickness of 1.3 *** reflection loss value could attain-10 dB in a wide frequency range of 2.7-18 GHz and thickness range of 1-5 *** addition,after high temperature and acid-alkali immersion treatment,this sample still had good EMW absorption capability,and the effective absorption bandwidth was enhanced from 2.3 to 2.6 GHz after concentrated acid immersion or 3.1 GHz after concentrated alkali *** work has great reference significance for the research and development of high-performance MAX-based EMW absorption materials in harsh environments.

关键词： MAX phases Solid solution Defects engineering Electromagnetic wave absorption Harsh environments

Fast flow simulation study of pulsating ventilation performance on air contaminant removal

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Building Simulation 2024年第8期17卷 1309-1322页

作者： Pengzhi zhou Haidong wang Yuwei Dai Chen Huang School of Environment and Architecture University of Shanghai for Science and Technology516 Jungong RoadShanghai200093China

Fast flow simulation is imperative in the design of pulsating ventilation,which is potentially efficient in indoor air contaminant *** execution of the conventional CFD method requires considerable amount of computational *** this study,five different numerical schemes were proposed based on fast fluid dynamics(FFD)and fractional step(FS)methods,and were evaluated to achieve quick simulation of airflow/contaminant *** of these numerical schemes was identified with the best overall computing efficiency for investigating the performance of pulsating *** this numerical scheme at hand,the air contaminant removal effectiveness of different ventilation types was *** kinds of pulsating ventilation and one kind of steady ventilation were tested upon a benchmark isothermal mixing *** effect of adjusting supply velocity parameters on the ventilation performance was also ***_(2)concentration,airflow pattern,and vortex structure of different ventilation types were illustrated and *** results reveal that the FS method is more suitable for transient simulation of wall-bounded indoor airflow than the FFD method,and 34%–51%of computing time could be saved compared to the conventional CFD *** the choice of ventilation type,steady ventilation might result in short-circuit airflow and stagnant zones;alternatively,pulsating ventilation has greater potential in air contaminant removal due to its ever-changing vortex structure.

关键词： pulsating ventilation fast fluid dynamics fractional step method contaminant removal efficiency time-periodic supply vortex structure

Sedimentary and Heavy Mineral Records for the Oligocene-Miocene Exhumation of the Easternmost Tianshan

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Journal of Earth Science 2024年第2期35卷 449-461页

作者： Yan Ding Tianyi Shen Guocan wang Junliang ji School of Earth Sciences Center for Global TectonicsChina University of GeosciencesWuhan430074China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan430078China Hubei Key Laboratory of Critical Zone Evolution School of Geography and Information EngineeringChina University of GeosciencesWuhan430074China

The topography of the Harlik Mountain has a strong impact on the formation of current arid climate in the Turpan-Hami ***,it is still controversial if Harlik Mountain experienced significant exhumation during the Middle to Late Cenozoic according to the previous thermochronology *** features of the Oligocene to Miocene sediments in the foreland basin could provide productive information for resolving the *** peak ages of detrital apatite fission track analysis of the Oligocene–Miocene sandstone in the Turpan-Hami Basin are well comparable with the cooling age records of the Harlik Mountain rocks,indicating that the Oligocene–Miocene Taoshuyuanzi Formation in the basin was mostly derived from the Harlik *** stratigraphic sequence exhibits coarsening upward,reflecting that the source area was in a tectonically active period during the deposition *** mineral assemblages also suggest that the unstable minerals in the sediment increased significantly at the end of the ***,the proportion of apatite increased up-section,while the garnet content decreased significantly,indicating that the Carboniferous metamorphic rocks have been gradually eroded out and more intrusive rocks have been exposed to the *** observations suggest that the Harlik Mountain experienced exhumation during the Oligocene to Miocene,and the denudation depth afterward was probably less than 2.5 km according to the previously apatite(U-Th)/He *** Oligocene–Miocene exhumation probably acted as one of the triggers for the heavy drought of the Turpan-Hami Basin during the Middle–Late Neogene.

关键词： Turpan-Hami Basin Harlik Mountain Taoshuyuanzi Formation Oligocene–Miocene uplift sedimentology structural geology

Influence of in situ formed spinel in bonding phase on mechanical properties and air permeability of magnesia-chrome porous purging materials

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Journal of Iron and Steel Research International 2024年第6期31卷 1459-1472页

作者： Yi An Hao Liu zhou-fu wang Yan Ma Xi-tang wang The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Magnesia-chrome porous purging plugs are crucial functional components to remove inclusions and stabilize the flow field during iron and steel ***,practical applications of magnesia-chrome porous purging materials are stil hampered by the poor scouring resistance to molten steel and unstable air permeability owing to their low mechanical properties and uncontrollable pore ***,the particle-packing type magnesiachrome porous purging materials reinforced by in situ formed spinel were prepared using fused magnesia-chrome particles and Al powders as major raw *** results show that in situ formed spinel solid solutions in bonding phase led to the decreased median pore size and increased pore surface fractal dimension from the reactions between Al powders and magnesia-chrome particles and along with high-temperature sintering,bonding between magnesia-chrome particles and the resultant mechanical properties of materials were greatly ***,the results of air permeability tests and polynomial ftting indicated that the formation of spinel solid solutions was the main contributing factor for controllable air permeability,and pressure drop of porous purging materials was positively correlated with surface fractal dimension of ***,the as-prepared porous purging materials added with 6 wt.%Al powders obtained the maximum cold crushing strength(54.2 MPa)and hot modulus of rupture(12.9 MPa)with median pore size of 24.06μm and ftting non-Darcian permeability coefficient of 0.97×10^(-6)m.

关键词： Magnesia Chrome porous purging material Metallic Al-Spinel Mechanical strength Air permeability

Upwelling current and its relationship to the enrichment of organic matter in the Lower Silurian Longmaxi Formation, northern Chongqing-western Hubei area, southern China

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Journal of Palaeogeography 2024年第4期13卷 993-1015页

作者： Jun-Jun Shen jia-Kai Yan Peng-Wan wang Yu-Man wang Lin zhou Yu-Bing ji Min Xu Hubei Cooperative Innovation Center of Unconventional Oil and Gas of Yangtze University Hydrogeology and Engineering Geology Institute of Hubei Geological Bureau PetroChina Hangzhou Institute of Petroleum Geology PetroChina Research Institute of Petroleum Exploration and Development Exploration and Production Research Institute Zhejiang Oilfield Company Integrated Center of Exploration and Development

Upwelling currents play a crucial role in the enrichment of organic matter, yet the mechanisms driving this process remain incompletely understood due to methodological and data resolution limitations. In this paper, we employ a combination of biostratigraphic classification, qualitative methods, and quantitative methods to systematically analyze the sedimentological and geochemical characteristics of the Lower Silurian Longmaxi Formation in the northern Chongqing-western Hubei area, southern China. The relationship between the upwelling currents and organic matter enrichment in the shale of the Longmaxi Formation is investigated. Results indicate that the upwelling currents in the study area were primarily influenced by the foreland flexure process. From the Rhuddanian(flexure-sedimentation stage) to the Aeronian(flexure-migration stage), the more intense tectonic activity led to gradual opening of the barrier between the South Qinling Ocean and the Yangtze Platform, resulting in an increase in the influx of the oceanic current. The upwelling currents significantly contributed to the organic matter production, albeit without substantially affecting the preservation conditions. Throughout the succession of the Longmaxi Formation, the organic matter content decreased gradually from the passive continental margin to the foreland flexural stagnant basin, which was mainly due to deterioration of the preservation conditions as a result of sea level fall and increased terrigenous input. Despite the increase in the upwelling currents, they did not decisively control the organic matter enrichment. Spatially, during the Rhuddanian to Aeronian period, the organic matter content decreased similarly from the passive continental margin to the foreland flexural stagnant basin, influenced by reduced organic matter production caused by weakening of the upwelling currents and the worsening preservation conditions caused by sea-level fall. The terrigenous input had a relatively minor

关键词： Middle–Upper Yangtze Ordovician–Silurian transition Black shale Passive continental margin Foreland flexural stagnant basin Sedimentary paleoenvironment

A simple route for preparation of TRIP-assisted Si-Mn steel with excellent performance using direct strip casting

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2173-2181页

作者： Hui Xu Lejun zhou Wanlin wang Yang Yi School of Metallurgy and Environment Central South UniversityChangsha 410083China National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083China

The complex producing procedures and high energy-consuming limit the large-scale production and application of advanced high-strength steels(AHSSs).In this study,the direct strip casting(DSC)technology with unique sub-rapid solidification characteristics and cost advantages was applied to the production of low-alloy Si-Mn steel with the help of quenching&partitioning(Q&P)concept to address these *** this method with the conventional compact strip production(CSP)process,the initial microstructure formed under different solidification conditions and the influence of heat treatment processes on the final mechanical properties were *** results show that the initial structure of the DSC sample is a dual-phase structure composed of fine lath martensite and bainite,while the initial structure of the CSP sample consists of pearlite and *** volume fraction and carbon content of retained austenite(RA)in DSC samples are usually higher than those in CSP samples after the same Q&P *** samples typically demonstrate better comprehensive mechanical properties than the CSP *** DSC sample partitioned at 300℃ for 300 s(DSC-Pt300)achieves the best comprehensive mechanical properties,with yield strength(YS)of 1282 MPa,ultimate tensile strength(UTS)of 1501 MPa,total elongation(TE)of 21.5%,and product of strength and elongation(PSE)as high as 32.3 GPa·%.These results indicate that the excellent mechanical properties in low-alloy Si-Mn steel can be obtained through a simple process(DSC-Q&P),which also demonstrates the superiority of DSC technology in manufacturing AHSSs.

关键词： direct strip casting sub-rapid solidification quenching and partitioning TRIP-assisted AHSSs microstructure