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Journal of Central South University 2024年第6期31卷 1774-1789页

作者： zhang jin-hai NIE Kai-bo zhang jin-hua DENG Kun-kun LIU Zhi-long College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of High-end Compressor and System Technology Hefei 230031China

In this study,the Mg-3Zn-0.5Zr-χNd(χ=0,0.6)alloys were subjected to final rolling treatment with large deformation of 50%.The impact of annealing temperatures on the microstructure and mechanical properties was *** rolled Mg-3Zn-0.5Zr-0.6Nd alloy exhibited an ultimate tensile strength of 386 MPa,a yield strength of 361 MPa,and an elongation of 7.1%.Annealing at different temperatures resulted in reduced strength and obviously increased elongation for both *** mechanical properties for the Mg-3Zn-0.5Zr-0.6Nd alloy were achieved after annealing at 200℃,with an ultimate tensile strength of 287 MPa,a yield strength of 235 MPa,and an elongation of 26.1%.The numerous deformed microstructures,twins,and precipitated phases in the rolled alloy could impede the deformation at room temperature and increase the work hardening *** annealing,a decrease in the work hardening effect and an increase in the dynamic recovery effect were obtained due to the formation of fine equiaxed grains,and the increased volume fraction of precipitated phases,which significantly improved the elongation of the ***,the addition of Nd element could enhance the annealing recrystallization rate,reduce the Schmid factor difference between basal and prismatic slip systems,facilitate multi-system slip initiation and improve the alloy plasticity.

关键词： Mg-Zn-Zr-Nd alloy large final rolling deformation annealing temperatures microstructures mechanical properties

基于消费者品牌知识管理的智能广告创作模式研究——网络议程设置理论视角

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现代传播（中国传媒大学学报） 2024年第8期46卷 76-86页

作者：柳庆勇张金海三峡大学文学与传媒学院武汉工商学院武汉大学新闻与传播学院

广告主的数字营销战略目标是消费者品牌知识管理,但目前研究实质都是产品导向的智能广告创作模式。由于品牌传播的宏观时空结构为“广告主-媒介-消费者”,因此从网络议程设置理论视角来看,消费者品牌知识管理本质是品牌网络议程设置,即... 详细信息

广告主的数字营销战略目标是消费者品牌知识管理,但目前研究实质都是产品导向的智能广告创作模式。由于品牌传播的宏观时空结构为“广告主-媒介-消费者”,因此从网络议程设置理论视角来看,消费者品牌知识管理本质是品牌网络议程设置,即实现品牌知识网络显著性程度从传播者向受传者转移,但需先设计内容全面的结构化品牌知识。其过程是宏观与微观统一的时空转换;关键是时间顺序性品牌触点,包括两个侧面:“空间”转换为“时间”的媒介第二层级品牌议程设置;“时间”转换为“空间”的消费者品牌网络议程设置。而新技术赋能的高级智能广告创作系统实现时间顺序性品牌触点的机理,可概括为“控制、识别、创作、反馈”模型,这创新了一种具体情境下消费者导向的、基于消费者品牌知识管理的智能广告创作模式。

关键词：智能广告创作模式消费者品牌知识管理网络议程设置

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大数据背景下国外国家安全治理研究及启示

山东行政学院学报 2024年第5期 77-85页

作者：张金海中国社会科学院信息情报研究院北京100732

在国外,大数据运用于国家安全治理的研究存在基础理论重应用价值轻概念内涵,大数据来源重来源轻法律依据,运用方法重收集轻储存和处理,运用案例重非传统安全领域轻传统安全领域的鲜明特点。在借鉴域外经验的基础上,未来我国国家安全治... 详细信息

在国外,大数据运用于国家安全治理的研究存在基础理论重应用价值轻概念内涵,大数据来源重来源轻法律依据,运用方法重收集轻储存和处理,运用案例重非传统安全领域轻传统安全领域的鲜明特点。在借鉴域外经验的基础上,未来我国国家安全治理应构建与中国式现代化相适应的国家安全治理基础理论,开展大数据背景下国家安全治理交叉学科建设,构建科学的适宜解释中国本土国家安全治理问题的方法论体系,持续增强大数据背景下传统国家安全治理研究,依托最新大数据技术全面推进数字国家安全治理,不断完善大数据背景下我国国家安全治理的理论和实践。

关键词：大数据国际学界国家安全治理总体国家安全观整体性治理数字治理学科建设

MRI与X线联合评估乳腺非肿块样病变恶性风险的Logistic回归模型建立及应用评价

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中国临床医学影像杂志 2024年第6期35卷 401-405,417页

作者：姚远张海金张文婷刘辉卞巍嘉兴市妇幼保健院放射科浙江嘉兴314000

目的:基于MRI与X线特征建立乳腺非肿块样病变(Non-mass-like lesions,NML)恶性风险的预测模型,期望提高诊断准确率,为临床决策提供依据。方法:对我院2021年7月-2023年4月符合纳入标准的150例患者的资料进行回顾性分析,使用Logistic回归... 详细信息

目的:基于MRI与X线特征建立乳腺非肿块样病变(Non-mass-like lesions,NML)恶性风险的预测模型,期望提高诊断准确率,为临床决策提供依据。方法:对我院2021年7月-2023年4月符合纳入标准的150例患者的资料进行回顾性分析,使用Logistic回归构建NML恶性风险预测模型及列线图,采用校准曲线评估模型准确度,用受试者工作特征(ROC)曲线评估模型的诊断效能。结果:多因素分析显示簇状环形强化、时间-信号强度曲线(TIC)类型、ADC值、线样及段样分布钙化等影像特征是预测病变恶性风险的因素。基于MRI特征的模型的ROC曲线下面积为0.941,灵敏度为88.7%,特异度为86.6%。基于MRI联合X线特征的模型的ROC曲线下面积为0.951,灵敏度为91.5%,特异度为91.4%,校准曲线预测准确度较好。结论 :基于MRI联合X线特征建立的乳腺NML恶性风险Logistic回归模型诊断效能较高,具有一定的应用潜力。

关键词：乳腺肿瘤磁共振成像放射摄影术

Bi-Frobenius Algebra Structures on Quantum Complete Intersections

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1481-1504页

作者： hai jin Pu zhang School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai 200240P.R.China

This paper is to look for bi-Frobenius algebra structures on quantum complete intersections over field *** find a class of comultiplications,such that if√−1∈k,then a quantum complete intersection becomes a bi-Frobenius algebra with comultiplication of this form if and only if all the parameters qij=±***,it is proved that if√−1∈k then a quantum exterior algebra in two variables admits a bi-Frobenius algebra structure if and only if the parameter q=±√*** if−1/∈k,then the exterior algebra with two variables admits no bi-Frobenius algebra *** prove that the quantum complete intersections admit a bialgebra structure if and only if it admits a Hopf algebra structure,if and only if it is commutative,the characteristic of k is a prime p,and every ai a power of *** also provides a large class of examples of bi-Frobenius algebras which are not bialgebras(and hence not Hopf algebras).In commutative case,other two comultiplications on complete intersection rings are given,such that they admit non-isomorphic bi-Frobenius algebra structures.

关键词： Bi-Frobenius algebras coalgebras bialgebras Hopf algebras quantum complete intersections quantum exterior algebras

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生产信息化在油气田中的应用及效果研究

Dual template-induced construction of three-dimensional porous SiO2/NC/Co-CNTs heterostructure with highly dispersed active sites for efficient oxygen evolution reaction

科学与信息化 2024年第8期 34-36页

作者：刘燕张晋海邓启志西南油气田分公司川西北气矿四川绵阳 621700

随着信息技术的普及,各行各业迎来新的发展方向,而探析生产信息化在油气田中的应用及效果,既是顺应社会发展需求的必然选择,也是推动油气田生产信息化的主要途径.基于此,本文从油气田生产运行管理特点出发,详细分析生产信息化在油气田... 详细信息

随着信息技术的普及,各行各业迎来新的发展方向,而探析生产信息化在油气田中的应用及效果,既是顺应社会发展需求的必然选择,也是推动油气田生产信息化的主要途径.基于此,本文从油气田生产运行管理特点出发,详细分析生产信息化在油气田生产中的应用现状,以某油气田企业为案例,探析生产信息化在油气田中的应用路径及具体效果,旨在为油气田企业的更好发展提供意见参考.

关键词：生产信息化油气田应用

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Tungsten 2024年第3期6卷 585-595页

作者： hai-Qi zhang Xiao-Jun Zeng Qing-Qing zhang Zu-Liang zhang Chu-Long jin Rong-hai Yu School of Materials Science and Engineering Jingdezhen Ceramic University School of Materials Science and Engineering Beihang University

The development and exploration of efficient and economical electrocatalysts for oxygen evolution reaction（OER） represents the main bottleneck to unlocking a sustainable energy scenario based on elec trocataly tic water *** scale integration of three-dimensional（3D） porous heterostructure with highly dispersed active sites and good structural stability is ***,a dual template route is developed to construct the 3D porous SiO2/nitrogen-doped carbon（NC）/Co-carbon nano tubes（CNTs） hetero ***,the hard template（SiO2nano spheres） contributes to 3D porous structure,increases the specific surface area,and promotes the contact area of the *** the same time,the soft template（basic zinc carbonate） can control the growth of 1D CNTs and facilitate the exposure of the active ***,3D porous SiO2/NC/Co-CNTs hetero structure inherits highly dispersed Co nanoparticles coated by *** conductive channels and abundant N hetero atoms doping are reasonably constructed by a dual template ***,SiO2/NC/Co-CNTs catalyst provides an extraordinary activity for the OER in alkaline media,with a low overpotential of 298 mV at a current density of 10 mA·***,SiO2/NC/Co-CNTs hetero structure enables excellent long-term durability with a 10 mV decay in overpotential after 3000 cyclic voltammetry cycles,and 97% remain in current density over 20 *** is believed that this dual template strategy can provide a new and simple way to construct a highly dispersed active site in electrocatalysts.

关键词： Dual template High dispersion Porous heterostructure Conductive channels Oxygen evolution reaction

Stereoselective Self-Assembly of Chiral Metalla[2]Catenanes and Lemniscular Macrocycles

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CCS Chemistry 2024年第8期6卷 2000-2010页

作者： Shu-jin Bao hai-Ning zhang Guo-Xin jin Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials State Key Laboratory of Molecular Engineering of PolymersDepartment of ChemistryFudan UniversityShanghai 200433

Designing and stereoselectively constructing chiral mechanically interlocked molecules(MIMs)is a goal that many chemists are pursuing due to their potential in the development of functional molecular machines involved in catalysis,sensing,and chiroptical ***,the synthesis of enantiopure supramolecular entities with crystallographic structures remains ***,the stereoselective self-assembly of chiral metalla[2]catenanes interlocked by two D-shaped macrocycles was realized by combining long binuclear half-sandwich organometallic Cp*Rh^(III)(Cp*=η^(5)-pentamethylcyclopentadienyl)clip and ditopic monodentate ligand incorporating L-leucine *** resulting metalla[2]catenane displayed unique co-conformational mechanical helical chirality characteristics arising from the chirality transfer of the chiral ***,decreasing the length of the binuclear Cp*Rh^(III)clip and adjusting the steric hindrance of the amino-acid side chains(L-alanine and L-phenylalanine)in the ligands resulted in two lemniscular macrocycles with left-handed(M)-twisted conformational *** the best of our knowledge,the synthesized macrocycles are the first family of homochiral abnormal lemniscate-shaped organometallic macrocycles featuring figure-eight ***[2]catenanes and macrocycles with opposite chirality were also generated by employing corresponding D-amino acid ligands,as evidenced by single-crystal X-ray diffraction,nuclear magnetic resonance,mass,and circular dichroism *** present study demonstrates that homochiral MIMs can be accessed readily using amino acid–containing ligands through rational molecular design.

关键词： stereoselective synthesis chirality metallacatenanes twisted macrocycles aminoacid residues

Coordination-driven self-assembly of a molecular 818knot and molecular borromean rings

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Science China Chemistry 2024年第11期67卷 3652-3656页

作者： Xiang Gao Dong Liu hai-Ning zhang Guo-Xin jin Department of Chemistry Fudan University

We report the facile construction of a molecular 818knot and a molecular Borromean rings assembly through self-assembly directed by Cp*Rh corner units. Two curved ligands of similar size and shape were used in this study. The slight steric differences between the two ligands induce the formation of distinctly different topologies of the assembled products. The structures were confirmed by single-crystal X-ray analysis and nuclear magnetic resonance spectroscopy.

关键词： coordination-driven Cp*Rh 818 knot Borromean rings

Answering reachability queries with ordered label constraints over labeled graphs

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Frontiers of Computer Science 2024年第1期18卷 105-117页

作者： Daoliang HE Pingpeng YUAN hai jin National Engineering Research Center for Big Data Technology and System Services Computing Technology and System LabCluster and Grid Computing LabSchool of Computer Science&TechnologyHuazhong University of Science and TechnologyWuhan 430074China

Reachability query plays a vital role in many graph analysis *** researches proposed many methods to efficiently answer reachability queries between vertex *** many real graphs are labeled graph,it highly demands Label-Constrained Reachability(LCR)query inwhich constraint includes a set of labels besides vertex *** researches proposed several methods for answering some LCR queries which require appearance of some labels specified in constraints in the *** that constraint may be a label set,query constraint may be ordered labels,namely OLCR(Ordered-Label-Constrained Reachability)queries which retrieve paths matching a sequence of ***,no solutions are available for ***,we propose DHL,a novel bloom filter based indexing technique for answering OLCR *** can be used to check reachability between vertex *** the answers are not no,then constrained DFS is ***,we employ DHL followed by performing constrained DFS to answer OLCR *** show that DHL has a bounded false positive rate,and it's powerful in saving indexing time and *** experiments on 10 real-life graphs and 12 synthetic graphs demonstrate that DHL achieves about 4.8-22.5 times smaller index space and 4.6-114 times less index construction time than two state-of-art techniques for LCR queries,while achieving comparable query response *** results also show that our algorithm can answer OLCR queries effectively.

关键词： graph ordered-label-constrained reachability partial index bloom filter query processing