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Super-high bed sintering for iron ores: inhomogeneous phenomena and its mechanism during mineralizing

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Journal of Iron and Steel Research International 2024年第8期31卷 1850-1860页

作者： hui-bo liu liang-ping Xu Xi-duan Yang Zhong-lin Dong Qiang Zhong Guang-hui li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

The inhomogeneous sinter properties in super-high bed sintering have been reported in our previous *** inves-tigate the reasons for the inhomogeneous phenomena,detailed sampling and analysis of mixed material bed and sintered bed in super-high bed sintering plant were *** results indicated that the higher porosity and thinner dendrite of silico-ferrite of calcium and aluminum in the upper layer as well as dense structure and higher secondary hematite content in the lower layer led to the heterogeneities of mechanical strength and reduction properties exceeding 20%and 10%,*** the bed top downward,the basicity of mixed material decreased from 2.13 to 1.68 because the average particle size increased from 2.65 to 4.56 *** and fuels gathered in finer particles(-3 mm)of mixed material,and the-3 mm particles of mixed material generated more liquid phase than+3 mm *** heat input of super-high sintering bed was inhomogeneous due to the heat accumulation effect and unreasonable fuel *** inhomo-geneous sintering heat condition in sintering bed resulted in the different quantities and properties of liquid *** inhomogeneous quantities and properties of liquid phase that were influenced by inhomogeneous distribution of chemical composition,particle size,and heat input led to inhomogeneous mineralizing *** mineralizing condition is the key for homogeneous super-high bed sintering.

关键词： Iron ore Super-high bed sintering Mineralization Material segregation Heat accumulation

Super-high bed sintering for iron ores:behaviors,causes and solutions of horizontal segregation on strand

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Journal of Iron and Steel Research International 2024年第7期31卷 1590-1596页

作者： liang-ping Xu hui-bo liu Zhong-lin Dong Qiang Zhong Yu-chao Zhao Guang-hui li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Horizontal segregation has been a constraint to the development and application of super-high bed *** eliminate the horizontal segregation of super-high bed sintering,several typical sintering machines were sampled and analyzed,and theoretical calculation was made to compare the bed depth and their differences in different areas within the mixture ***,solutions were proposed and applied to a 265 m^(2) sintering *** results showed that the horizontal seg-regation of the 265 m^(2) sintering machine was dominated by particles larger than 8 mm with horizontal segregation degree of 0.48,while 360 and 550 m^(2) sintering machines were affected by 5-8 mm and 1-3 mm particles with horizontal segregation degree of 0.27 and 0.31,*** analysis indicated the different segregation distribution results from the matching of the bed depth of each area within the mixture ***,the horizontal segregation degree not larger than 0.06 was achieved by optimizing the time parameters and the division of three zones on the 265 m^(2) sintering machine.

关键词： Super-high bed sintering Horizontal segregation Feeder Particle distribution Agglomeration

A General Framework for Intelligent IoT Data Acquisition and Sharing in an Untrusted Environment Based on Blockchain

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China Communications 2024年第3期21卷 137-148页

作者： Lu yin Xue Yongtao li Qingyuan Wu Luocheng li Taosen Yang Peipei Zhu Hongbo College of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China Key Lab of Broadband Wireless Communication and Sensor Network Technology(Nanjing University of Posts and Telecommunications) Ministry of EducationNanjing 210003China Jiangsu Key Laboratory of Wireless Communications Nanjing University of Posts and TelecommunicationsNanjing 210003China Research Institute of Internet of Things Nanjing University of Posts and TelecommunicationsNanjing 210003China Bell Honors School Nanjing University of Posts and TelecommunicationsNanjing 210023China School of Automation Nanjing University of Posts and TelecommunicationsNanjing 210023China

Traditional Io T systems suffer from high equipment management costs and difficulty in trustworthy data sharing caused by *** provides a feasible research direction to solve these problems. The main challenge at this stage is to integrate the blockchain from the resourceconstrained Io T devices and ensure the data of Io T system is credible. We provide a general framework for intelligent Io T data acquisition and sharing in an untrusted environment based on the blockchain, where gateways become Oracles. A distributed Oracle network based on Byzantine Fault Tolerant algorithm is used to provide trusted data for the blockchain to make intelligent Io T data trustworthy. An aggregation contract is deployed to collect data from various Oracle and share the credible data to all on-chain users. We also propose a gateway data aggregation scheme based on the REST API event publishing/subscribing mechanism which uses SQL to achieve flexible data aggregation. The experimental results show that the proposed scheme can alleviate the problem of limited performance of Io T equipment, make data reliable, and meet the diverse data needs on the chain.

关键词： blockchain data sharing Internet of Things Oracle

Astronomical influence of the development of Paleogene thin coal seam groups in offshore Lacustrine basins:A case study of the ZhuⅠDepression's Enping Formation located in the northern South China Sea

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Acta Oceanologica Sinica 2024年第4期43卷 136-150页

作者： Yan liu Shengbing Huang Dongdong Wang Nan li Yuting yin ying Chen Zengxue li College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China CNOOC Research Institute Co. Ltd.Beijing 100028China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTUK

The development of the Paleogene coal seams in China's offshore basin areas generally had the characteristics of coal measures with large thicknesses,large numbers of coal seams,thin single coal seams,poor stability,scattered vertical distribution,and a wide distribution *** study selected the Enping Formation of the ZhuⅠDepression in the northern section of the South China Sea as an example to determine the macro-control factors of the development of the Paleogene coal seam *** analysis was carried out on the influencing effects and patterns of the astronomical cycles related to the development of the thin coal seam groups in the region.A floating astronomical time scale of the Enping Formation was established,and the sedimentary time limit of the Enping Formation was determined to be approximately 6.15 Ma±.In addition,the cyclostratigraphy analysis results of the natural gamma-ray data of Well XJ in the Enping Formation of the Xijiang Sag revealed that the development of the thin coal seams had probably been affected by short eccentricity and precession *** formation process of coal seams was determined to have been affected by high seasonal contrast,precipitation,and *** the periods with high values of short eccentricity,the seasonal contrasts tended to be *** those periods,fluctuations in the precession controls resulted in periodic volume changes in precipitation and insolation of the region,resulting in the development of thin coal *** was also found that the periods with low precession were the most conducive to coal seam *** that basis,combined with such factors as sedimentary environmental conditions conducive to the development of thin coal seam groups,this study established a theoretical model of the comprehensive influences of short eccentricity and precession on the development and distribution of Paleogene thin coal seam groups in offshore lacustrine *** patterns of the Paleogene astrono

关键词： Paleogene Pearl(Zhujiang)River Mouth Basin coal seam development astronomical cycles

Performances of fissured red sandstone after thermal treatment with constant-amplitude and low-cycle impacts

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 561-587页

作者： Yongjun Chen Tubing yin P.G.Ranjith Xibing li Qiang li Dengdeng Zhuang School of Resources and Safety Engineering Central South UniversityChangsha410083China Department of Civil Engineering Monash UniversityMelbourne3800Australia Oulu Mining School University of OuluOuluFI-90014Finland

In the engineering practices,it is increasingly common to encounter fractured rocks perturbed by temperatures and frequent dynamic *** this paper,the dynamic behaviors and fracture characteristics of red sandstone considering temperatures(25℃,200℃,400℃,600℃,and 800℃)and fissure angles(0°,30°,60°,and 90°)were evaluated under constant-amplitude and low-cycle(CALC)impacts actuated by a modified split Hopkinson pressure bar(SHPB)***,fracture morphology and second-order statistics within the grey-level co-occurrence matrix(GLCM)were examined using scanning electron microscopy(SEM).Meanwhile,the deep analysis and discussion of the mechanical response were conducted through the synchronous thermal analyzer(STA)test,numerical simulations,one-dimensional stress wave theory,and material *** multiple regression models between response variables and interactive effects of independent variables were established using the response surface method(RSM).The results demonstrate the fatigue strength and life diminish as temperatures rise and increase with increasing fissure angles,while the strain rate exhibits an inverse ***,the peak stress intensification and strain rate softening observed during CALC impact exhibit greater prominence at increased fissure *** failure is dominated by tensile damage with concise evolution paths and intergranular cracks as well as the compressor-crushed zone which may affect the failure mode after 400℃.The second-order statistics of GLCM in SEM images exhibit a considerable dependence on the ***,thermal damage dominated by thermal properties controls the material structure and wave impedance and eventually affects the incident wave *** tensile wave reflected from the fissure surface is the inherent mechanism responsible for the angle effect exhibited by the fatigue strength and ***,the peak stress intensification and strain rate softening during impact are determ

关键词： Red sandstone Temperature Fissure Constant-amplitude and low-cycle(CALC) impact Fatigue failure Response surface method(RSM)

Stable stripe and vortex solitons in two-dimensional spin-orbit coupled Bose-Einstein condensates

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Communications in Theoretical Physics 2024年第6期76卷 26-33页

作者： Yuan Guo Muhammad Idrees Ji lin hui-jun li Institute of Nonlinear Physics and Department of Physics Zhejiang Normal UniversityJinhua 321004China Zhejiang Institute of Photoelectronics and Zhejiang Institute for Advanced light Source Zhejiang Normal UniversityJinhua 321004China

We present a flexible manipulation and control of solitons via Bose-Einstein *** the presence of Rashba spin-orbit coupling and repulsive interactions within a harmonic potential,our investigation reveals the numerical local solutions within the *** manipulating the strength of repulsive interactions and adjusting spin-orbit coupling while maintaining a zero-frequency rotation,diverse soliton structures emerge within the *** include plane-wave solitons,two distinct types of stripe solitons,and odd petal solitons with both single and double *** stability of these solitons is intricately dependent on the varying strength of spin-orbit ***,stripe solitons can maintain a stable existence within regions characterized by enhanced spin-orbit coupling while petal solitons are unable to sustain a stable existence under similar *** rotational frequency is introduced to the system,solitons undergo a transition from stripe solitons to a vortex array characterized by a sustained *** rotational directions of clockwise and counterclockwise are non-equivalent owing to spin-orbit *** a result,the properties of vortex solitons exhibit significant variation and are capable of maintaining a stable existence in the presence of repulsive interactions.

关键词： Bose-Einstein condensate spin-orbit coupling rotation frequency stripe solitons vortex array

Sulfonated carbon dots modified IrO_(2)nanosheet as durable and high-efficient electrocatalyst for boosting acidic oxygen evolution reaction

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Nano Research 2024年第9期17卷 8017-8024页

作者： Mengjie Ma Wenxiang Zhu Fan liao Kui yin hui Huang Kun Feng Dongdong Gao Jinxin Chen Zenan li Jun Zhong Lai Xu Yang liu Mingwang Shao Zhenhui Kang Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Macao Institute of Materials Science and Engineering(MIMSE) Macao University of Science and TechnologyTaipaMacao 999078China

Oxygen evolution reaction(OER)plays a crucial role in developing energy conversion and adjusting electronic structure of the electrocatalysts can effectively improve the catalytic activity and ***,it is a challenge to adjust the electronic structure on two-dimensional iridium dioxide nanosheets(IrO_(2)NS),which have the advantages of high atom ***,we regulate the surface properties of IrO_(2)NS through sulfonated carbon dots(SCDs)to promote the OER catalytic *** catalyst IrO_(2)NS/SCDs-2 exhibited excellent catalytic activity with a lower overpotential of 180 mV than IrO_(2)NS(230 mV)at the current density of 10 mA·cm^(-2)in a 0.5 M H_(2)SO_(4) *** after 160 h of stability testing,the overpotential of IrO_(2)NS/SCDs-2 only decreased by 4 ***,transient potential scanning test can visually demonstrate that the addition of SCDs improves the conductivity of the catalyst and increases the electron transfer rate.

关键词： sulfonated carbon dots oxygen evolution reaction electrocatalysis transient potential scanning

Historical Changes and Multi-scenario Prediction of Land Use and Terrestrial Ecosystem Carbon Storage in China

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Chinese Geographical Science 2024年第3期34卷 487-503页

作者： AN Yue TAN Xuelan REN hui li yinqi ZHOU Zhou College of Resources Hunan Agricultural UniversityChangsha 410128China School of Geographic Science Hunan Normal UniversityChangsha 410081China

Terrestrial carbon storage(CS)plays a crucial role in achieving carbon balance and mitigating global climate *** study employs the Shared Socioeconomic Pathways and Representative Concentration Pathways(SSPs-RCPs)published by the Intergovernmental Panel on Climate Change(IPCC)and incorporates the Policy Control Scenario(PCS)regulated by China’s land management *** Future Land Use Simulation(FLUS)model is employed to generate a 1 km resolution land use/cover change(LUCC)dataset for China in 2030 and *** on the carbon density dataset of China’s terrestrial ecosystems,the study analyses CS changes and their relationship with land use changes spanning from 1990 to *** findings indicate that the quantitative changes in land use in China from 1990 to 2020 are characterised by a reduction in the area proportion of cropland and grassland,along with an increase in the impervious surface and forest *** changing trend is projected to continue under the PCS from 2020 to *** the SSPs-RCPs scenario,the proportion of cropland and impervious surface predominantly increases,while the proportions of forest and grassland continuously *** loss in China’s carbon storage from 1990 to 2020 amounted to 0.53×10^(12)kg,primarily due to the reduced area of cropland and *** the SSPs-RCPs scenario,more significant carbon loss occurs,reaching a peak of8.07×10^(12)kg in the SSP4-RCP3.4 *** loss is mainly concentrated in the southeastern coastal area and the Beijing-TianjinHebei(BTH)region of China,with urbanisation and deforestation identified as the primary *** the future,it is advisable to enhance the protection of forests and grassland while stabilising cropland areas and improving the intensity of urban *** research findings offer valuable data support for China’s land management policy,land space optimisation,and the achievement of dual-carbon targets.

关键词： land use change Future Land Use Simulation(FLUS)model carbon storage carbon density dataset land use scenario China

Influence of varied drought types on soil conservation service within the framework of climate change:insights from the Jinghe River Basin,China

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Journal of Arid Land 2024年第2期16卷 220-245页

作者： BAI Jizhou li Jing RAN hui ZHOU Zixiang DANG hui ZHANG Cheng YU Yuyang School of Geography and Tourism Shaanxi Normal UniversityXi'an 710119China College of Geomatics Xi'an University of Science and TechnologyXi'an 710054China

Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,*** the influence of drought on soil conservation service is of great importance to regional environmental protection and sustainable ***,there is little research on the coupling relationship between *** this study,focusing on the Jinghe River Basin,China as a case study,we conducted a quantitative evaluation on meteorological,hydrological,and agricultural droughts(represented by the Standardized Precipitation Index(SPI),Standardized Runoff Index(SRI),and Standardized Soil Moisture Index(SSMI),respectively)using the Variable Infiltration Capacity(VIC)model,and quantified the soil conservation service using the Revised Universal Soil Loss Equation(RUSLE)in the historical period(2000-2019)and future period(2026-2060)under two Representative Concentration Pathways(RCPs)(RCP4.5 and RCP8.5).We further examined the influence of the three types of drought on soil conservation service at annual and seasonal *** NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)dataset was used to predict and model the hydrometeorological elements in the future period under the RCP4.5 and RCP8.5 *** results showed that in the historical period,annual-scale meteorological drought exhibited the highest intensity,while seasonal-scale drought was generally weakest in autumn and most severe in *** intensity of all three types of drought will increase over the next 40 years,with a greater increase under the RCP4.5 scenario than under the RCP8.5 ***,the intra-annual variation in the drought intensity of the three types of drought becomes smaller under the two future scenarios relative to the historical period(2000-2019).Soil conservation service exhibits a distribution pattern characterized by high levels in the southwest and southeast and lower levels in the north,and this pattern has remained

关键词： meteorological drought hydrological drought agricultural drought soil conservation service Variable Infiltration Capacity(VIC)model Revised Universal Soil Loss Equation(RUSLE) Jinghe River Basin