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Instrumented oscillographic study on impact toughness of an axle steel DZ2 with different tempering temperatures

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1590-1598页

作者： Shuo Liu peng Zhang Bin Wang Kaizhong Wang Zikuan Xu Fangzhong hu Xin Bai Qiqiang Duan Zhefeng Zhang Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Technology Center Ma'anshan Iron and Steel Co.Ltd.Ma'anshan 243000China

Compared with the conventional Charpy impact test method,the oscillographic impact test can help in the behavioral analysis of materials during the fracture *** this study,the trade-off relationship between the strength and toughness of a DZ2 axle steel at various tempering temperatures and the cause of the improvement in impact toughness was *** tempering process dramatically influenced carbide precipitation behavior,which resulted in different aspect ratios of *** toughness improved along with the rise in tempering temperature mainly due to the increase in energy required in impact crack *** characteristics of the impact crack propagation process were studied through a comprehensive analysis of stress distribution,oscilloscopic impact statistics,fracture morphology,and carbide *** poor impact toughness of low-tempering-temperature specimens was attributed to the increased number of stress concentration points caused by carbide morphology in the small plastic zone during the propagation process,which resulted in a mixed distribution of brittle and ductile fractures on the fracture surface.

关键词： axle steel DZ2 tempering process impact toughness oscillographic impact test impact crack propagation carbides

Experimental Study on Vortex-Induced Vibration of Rough Risers Coupling with Interference Effect in Tandem Arrangement

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China Ocean Engineering 2024年第3期38卷 394-407页

作者： hu Ze-bo LIU Zhen LI peng GUO Hai-yan REN Xiao-hui HOU Hao HAO Lian-hong College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao 266590China Qingdao Key Laboratory of Marine Civil Engineering Materials and Structures Qingdao 266590China College of Engineering Ocean University of ChinaQingdao 266100China

In order to study the response law of vortex-induced vibration(VIV)of marine risers under the combined action of roughness and interference effects,and to reveal the coupling mechanism of roughness and interference effects on the riser,a VIV experiment of rough risers in tandem arrangement was conducted in a wave−current combined *** experiment characterized the risers’roughness by arranging different specifications of attachments on the surface of the *** rough risers with different roughness and smooth risers were arranged in tandem arrangement,with the rough risers arranged *** experimental results indicate that the suppression of the attachments on the downstream risers’vibration are more significant both in the CF and IL directions as the reduced velocity *** the downstream riser,the amplitude response of rough riser is more significantly weakened compared with the smooth one at high reduced *** the upstream risers,changes in the roughness and spacing ratio have an impact on their‘lock-in’*** the roughness of downstream risers is relatively large(0.1300)and the spacing between risers is small(S/D=4.0),the reduced velocity range of‘lock-in’region in the CF direction of upstream risers is obviously expanded,and the displacement in the‘lock-in’region is severer.

关键词： marine riser vortex-induced vibration tandem arrangement roughness interference effect

Effect of lanthanum on inclusions in non-oriented electrical steel slabs

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Journal of Iron and Steel Research International 2024年第7期31卷 1680-1691页

作者： Qiang Ren Zhi-yuan hu yun-xia Liu Wei-cheng Zhang Zi-qi Gao Li-feng Zhang School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004HebeiChina School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Research and Development Department Shougang Zhixin Qian'an Electromagnetic Material Co.Ltd.Qian'an 064400HebeiChina School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China

The effect of lanthanum on the characteristics of inclusions in the slab of non-oriented electrical steels was investigated through industrial trials and thermodynamic *** number,size,and chemical composition of inclusions in the surface,one-quarter of thickness and the center of slabs with and without lanthanum addition were statistically analyzed using an automatic inclusion analysis *** the lanthanum-free slab,inclusions were predominately ***_(2)O_(3),MgO,and AlN as well as a small number of Al_(2)O_(3)-MgO-CaO and *** number densities of oxide inclusions and AlN decreased from the surface to the center of the slab,which was ascribed to the difference in cooling intensity during the continuous *** the steel with lanthanum addition,inclusions were modified into LaAlO_(3) and La_(2)O_(2)S and gradually transformed into dual-phase MgO-La_(2)S3 with an increasing distance from the slab surface due to the reaction between the lanthanum-containing inclusion and the steel *** uneven distribution of oxide inclusions along the thickness of the slab was eliminated in the lanthanum-bearing slab because the dissolved oxygen was remarkably decreased by ***-bearing inclusions were more likely to agglomerate AlN by inducing the heterogeneous nucleation of AlN on their surface,while small-size ***_(2)O_(3) inclusions hardly showed a coarsening effect on the size of AlN.

关键词： Lanthanum-Inclusion Non-oriented electrical steel Aluminum nitride Heterogenous nucleation

Data Component:An Innovative Framework for Information Value Metrics in the Digital Economy

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China Communications 2024年第5期21卷 17-35页

作者： Tao Xiaoming Wang Yu peng Jieyang Zhao Yuelin Wang Yue Wang Youzheng hu Chengsheng Lu Zhipeng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Beijing 100084China China Electronics Corporation Beijing 100084China

The increasing dependence on data highlights the need for a detailed understanding of its behavior,encompassing the challenges involved in processing and evaluating ***,current research lacks a comprehensive structure for measuring the worth of data elements,hindering effective navigation of the changing digital *** paper aims to fill this research gap by introducing the innovative concept of“data components.”It proposes a graphtheoretic representation model that presents a clear mathematical definition and demonstrates the superiority of data components over traditional processing ***,the paper introduces an information measurement model that provides a way to calculate the information entropy of data components and establish their increased informational *** paper also assesses the value of information,suggesting a pricing mechanism based on its *** conclusion,this paper establishes a robust framework for understanding and quantifying the value of implicit information in data,laying the groundwork for future research and practical applications.

关键词： data component data element data governance data science information theory

Rhizosphere microbes influence wogonoside accumulation in perennial Scutellaria baicalensis

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Pedosphere 2024年第3期34卷 553-566页

作者： Yang SUN Hong LIU Junwei peng Minchong SHEN Yang hu Dongsheng YU Jiangang LI Yuanhua DONG CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao 266101(China)

Dried roots of Scutellaria baicalensis Georgi are an acclaimed traditional Chinese medicine,and wogonoside content is a key indicator used to evaluate *** *** than rising linearly with cultivation years,*** quality initially increases and then ***,little is known regarding the dynamic variations in *** rhizosphere microorganisms under long-term cultivation and underlying mechanisms of their effects on wogonoside formation and *** aim of this study was to investigate the roles of soil nutrients and rhizosphere microbes on *** quality across different cultivation years(1-4 years).The wogonoside content(25.14 mg g^(-1))was highest in the biennial *** and then decreased following long-term *** soil nutrients(available nitrogen,available phosphorus,available iron,available manganese,and available zinc)were reduced significantly as cultivation years *** also affected rhizosphere bacterial community structure significantly,driving it toward deterministic process(i.e.,β-nearest taxon index<-2).Available manganese and exchangeable calcium indirectly affected wogonoside formation and *** inhibition was driven by the reduction in rhizosphere bacterial diversity,which significantly increased the relative abundance of beta-glucosidase and decreased the relative abundance of phenylalanine *** rhizosphere microenvironment was altered under long-term cultivation,thereby shaping rhizosphere bacterial community,reducing the community diversity,and ultimately inhibiting wogonoside formation and *** findings may aid in understanding of the mechanisms and reasons for the reduction in *** quality under long-term cultivation from the perspective of soil nutrients and microorganisms,which may theoretically support the future artificial cultivation and management of Chinese medicinal plants.

关键词： bacterial diversity medicinal plant rhizosphere bacterial community soil nutrient wogonoside content wogonoside formation

NextPolish2:A Repeat-aware Polishing Tool for Genomes Assembled Using HiFi Long Reads

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Genomics, Proteomics & Bioinformatics 2024年第1期22卷 105-109页

作者： Jiang hu Zhuo Wang Fan Liang Shan-Lin Liu Kai Ye De-peng Wang School of Automation Science and Engineering Faculty of Electronic and Information EngineeringXi’an Jiaotong UniversityXi’an 710049China GrandOmics Biosciences Beijing 102206China Department of Entomology College of Plant ProtectionChina Agricultural UniversityBeijing 100193China

The high-fidelity(HiFi)long-read sequencing technology developed by PacBio has greatly improved the base-level accuracy of genome ***,these assemblies still contain base-level errors,particularly within the error-prone regions of HiFi long *** genome polishing tools usually introduce overcorrections and haplotype switch errors when correcting errors in genomes assembled from HiFi long ***,we describe an upgraded genome polishing tool-NextPolish2,which can fix base errors remaining in those“highly accurate”genomes assembled from HiFi long reads without introducing excessive overcorrections and haplotype switch *** believe that NextPolish2 has a great significance to further improve the accuracy of telomere-to-telomere(T2T)***2 is freely available at https://***/Nextomics/NextPolish2.

关键词： Telomere-to-telomere Genome assembly Genome polishing Error correction HiFi long read

Study on Shear Strength Characteristics of Basalt-Concrete Bonding Interface Based on in-situ Direct Shear Test

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Journal of Earth Science 2024年第2期35卷 553-567页

作者： peng Xia Xinli hu Chunye Ying Shuangshuang Wu Chu Xu Xuan Wang Hao Chen Hang Duan College of Harbour and Coastal Engineering Jimei UniversityXiamen361021China Faculty of Engineering China University of GeosciencesWuhan430074China China Three Gorges Construction Group Ltd.Beijing100038China

In rock engineering,the shear strength of the basalt-concrete bonding interface is a key factor affecting the shear performance of hydroelectric dam foundations,embedded rock piles and rock *** this study,30 sets of in-situ direct shear tests were conducted on the basalt-concrete bond interface in the Baihetan dam area to investigate the shear strength characteristics of the basalt-concrete bonding *** bonding interface contains two states,i.e.,the bonding interface is not sheared,termed as se(symbolic meaning see Table 1);the bonding interface is sheared with rupture surface,termed as *** effects of lithology,Joints structure,rock type grade and concrete compressive strength on the shear strength of the concrete-basalt contact surface were *** test results show that the shear strength of the bonding interface(s_(e)&s_(i))of columnar jointed basalt with concrete is greater than that of the bonding interface(s_(e)&s_(i))of non-columnar jointed one with the same rock type *** the rock type grade isⅢ_(2),fcol is 1.22 times higher than fncol and ccol is 1.13 times greater than *** shear strength parameters of the basalt-concrete bonding interface differ significantly for different *** cohesion of the bonding interface(s_(i))of cryptocrystalline basalt with concrete is 2.05 times higher than that of the bonding interface(s_(i))of breccia lava with concrete under the same rock type grade *** type grade has a large influence on the shear strength of the non-columnar jointed basalt-concrete bonding interface(s_(e)&s_(i)).cnol increases by 33%when the grade of rock type rises fromⅢ_(1)toⅡ_(1).the rock type grade has a greater effect on bonding interface(s_(i))cohesion than the coefficient of *** the rock type grade is reduced fromⅢ_(2)toⅢ_(1),f_(ncol)′increases by 2%and c_(ncol)′improves by 44%.The shear strength of the non-columnar jointed basalt-concrete bonding interface(s_(e)&s_(i))increases wit

关键词： direct shear test basalt-concrete bonding interface shear strength parameters engineering geogolgy

天线组阵中基于SUMPLE算法的故障天线分析

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宇航学报 2011年第11期32卷 2445-2450页

作者：沈彩耀胡赟鹏于宏毅信息工程大学信息工程学院郑州450002

在大规模天线组阵中,故障天线所引入的噪声会增加阵列的合成输出损失,而在低信噪比下难以用信号检测算法判断组阵天线是否存在故障。针对该问题,在分析故障天线对信号合成影响的基础上,本文提出一种基于SUMPLE算法的权值幅度修正方法实... 详细信息

在大规模天线组阵中,故障天线所引入的噪声会增加阵列的合成输出损失,而在低信噪比下难以用信号检测算法判断组阵天线是否存在故障。针对该问题,在分析故障天线对信号合成影响的基础上,本文提出一种基于SUMPLE算法的权值幅度修正方法实现天线增益分析,并分析了修正因子对降低故障天线影响的有效性。理论分析与仿真结果表明,权值幅度修正算法能明显降低故障天线的权值幅度,减少了合成增益损失,有利于在大规模天线组阵中故障天线的检测,具有重要的工程应用价值。

关键词：天线组阵 SUMPLE算法合成权值故障天线

Numerical study on local scour characteristics around submarine pipelines in the Yellow River Delta silty sandy soil under waves and currents

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Deep Underground Science and Engineering 2024年第2期3卷 182-196页

作者： peng Yu Ruigeng hu Jike Zhang Qi Yang Jieru Zhao Lei Cao Chenghao Zhu Key Laboratory of Geological Safety of Coastal Urban Underground Space Ministry of Natural ResourcesQingdaoChina Qingdao Geo-Engineering Surveying Institute(Qingdao Geological Exploration Development Bureau) QingdaoChina Sinopec Petroleum Engineering Corporation DongyingChina State Key Laboratory of Hydroscience and Engineering Tsinghua UniversityBeijingChina Department Civil and Environmental Engineering Politecnico di MilanoMilanItaly College of Environmental Science and Engineering Ocean University of ChinaQingdaoChina

Due to their high reliability and cost-efficiency,submarine pipelines are widely used in offshore oil and gas resource *** to the interaction of waves,currents,seabed,and pipeline structures,the soil around submarine pipelines is prone to local scour,severely affecting their operational *** the Yellow River Delta as the research area and based on the renormalized group(RNG)k-εturbulence model and Stokes fifth-order wave theory,this study solves the Navier-Stokes(N-S)equation using the finite difference *** volume of fluid(VOF)method is used to describe the fluid-free surface,and a threedimensional numerical model of currents and waves-submarine pipeline-silty sandy seabed is *** rationality of the numerical model is verified using a self-built waveflow *** this basis,in this study,the local scour development and characteristics of submarine pipelines in the Yellow River Delta silty sandy seabed in the prototype environment are explored and the influence of the presence of pipelines on hydrodynamic features such as surrounding flow field,shear stress,and turbulence intensity is *** results indicate that(1)local scour around submarine pipelines can be divided into three stages:rapid scour,slow scour,and stable *** maximum scour depth occurs directly below the pipeline,and the shape of the scour pits is asymmetric.(2)As the water depth decreases and the pipeline suspension height increases,the scour becomes more intense.(3)When currents go through a pipeline,a clear stagnation point is formed in front of the pipeline,and the flow velocity is positively correlated with the depth of *** study can provide a valuable reference for the protection of submarine pipelines in this area.

关键词： local scour numerical simulation submarine pipelines Yellow River Delta