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Journal of Iron and Steel Research International 2021年第10期28卷 1212-1222页

作者： Feng zhang de-qing Zhu Jian Pan Zheng-qi Guo Meng-jie Xu College of Materials and Metallurgy Guizhou UniversityGuiyang550025GuizhouChina School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina Sinosteel Equipment&Engineering Co. Ltd.Beijing100080China

The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was *** fired pellets in the basicity range of 0.09(natural basicity)to 1.00 show superior reducibility and low-temperature disintegration ***,in the basicity range of 0.20–0.80,the abnormal swelling of the fired pellets *** basicity from 0.09 to 0.40 promotes the generation of low melting point slag phases and lower porosity of fired pellets,and accelerates the growth and densification of hematite crystals,impeding the reduction of hematite particles and the formation of metallic iron *** addition,the slags that distribute between the hematite particles absorb the reduction stresses by increased distances between the particles during the reduction process,which leads to the large reduction swelling of pellets.

关键词： Ultrafine high-grade magnetite concentrate Basicity Metallurgical performance Reduction behavior Gas-based shaft furnace direct reduction Fired pellet

Improving roasting performance and consolidation of pellets made of ultrafine and super high grade magnetite concentrates by modifying basicity

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Journal of Iron and Steel Research International 2020年第7期27卷 770-781页

作者： Feng zhang de-qing Zhu Jian Pan Zheng-qi Guo Meng-jie Xu School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina Sinosteel Equipment&Engineering Co. Ltd.Beijing 100000China

For improving the strength of pellets made of ultrafine and super-high-grade magnetite concentrates,the influence of basicity(CaO/SiO2 ratio)on the roasting and consolidation of pellets was *** results showed that with the basicity of pellets increasing from 0.09 to 0.60,the compressive strength of both preheated and roasted pellets achieved an evident improvement from 502 and 2519 to 549 and 3096 N/pellet,respectively;meanwhile,the roasting time decreased from 15 to *** low-viscosity liquid phases were easily generated in fired pellets at the basicity range of 0.40-0.60 under the roasting temperature of 1240℃,filled the voids between hematite particles and tightened the bonding among particles,effectively restraining the generation of concentric cracks and decreasing the porosity of fired pellets;low-viscosity liquid phases facilitated the solid diffusion of hematite,leading to the formation of coarse hematite crystals and thicker connecting necks.

关键词： Basicity Consolidation Ultrafine and super-high-grade magnetite concentrate Fired pellet Compressive strength Liquid phase

Recent advances in multifunctional shape memory photonic crystals and practical applications

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Nano Research 2024年第1期17卷 79-96页

作者： Yong qi Shufen zhang State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsDalian University of TechnologyDalian 116024China

Shape memory photonic crystals(SMPCs)are smart composite materials with changeable structural color integrated by shape memory polymer and photonic *** can produce one or more temporary shapes through nanoscale deformation,memorizing current *** can be recovered to their original shapes or some intermediate states under external stimuli,accompanied by the variation of structural *** porous carriers with built-in sensing properties,SMPCs promoted the interdisciplinary development of nanophotonic technology in materials science,environmental engineering,biomedicine,chemical engineering,and ***,the recent progress on multifunctional SMPCs and practical applications,including traditional and cold programmable SMPCs,is summarized and *** primary concern is shape programming at the nanoscale that has demonstrated numerous attractive functions,including smart sensing,ink-free printing,solvent detection,reprogrammable gradient wetting,and controllable bubble transportation,under variations of the surface *** aims to figure out the nanoscale shape memory effects on structural color conversion and additional performance,inspiring the fabrication of the next generation of ***,perspectives on future research directions and applications are also *** is believed that multifunctional SMPCs are powerful nanophotonic tools for the interdisciplinary development of numerous disciplines in the future.

关键词： photonic crystal shape memory structural color cold programmable shape recovery

Certificateless threshold signature from lattice

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Digital Communications and Networks 2024年第4期10卷 965-972页

作者： Huifang Yu qi zhang School of Cyberspace Security Xi'an University of Posts and TelecommunicationsXi'anChina

Threshold signature has been widely used in electronic wills,electronic elections,cloud computing,secure multiparty computation and other *** now,certificateless threshold signature schemes are all based on traditional mathematic theory,so they cannot resist quantum computing *** view of this,we combine the advantages of lattice-based cryptosystem and certificateless cryptosystem to construct a certificateless threshold signature from lattice(LCLTS)that is efficient and resistant to quantum algorithm *** has the threshold characteristics and can resist the quantum computing attacks,and the analysis shows that it is unforgeable against the adaptive Chosen-Message Attacks(UF-CMA)with the difficulty of Inhomogeneous Small Integer Solution(ISIS)*** addition,LCLTS solves the problems of the certificate management through key escrow.

关键词： Lattice Threshold signature Inhomogeneous small integer solution Certificateless public key Lattice sampling technique

Some Remarks on One-dimensional Functions and Their Riemann–Liouville Fractional Calculus

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Acta Mathematica Sinica,English Series 2014年第3期30卷 517-524页

作者： qi zhang Faculty of Science Nanjing University of Aeronautics and Astronautics

A one-dimensional continuous function of unbounded variation on [0, 1] has been con- structed. The length of its graph is infinite, while part＂ of this function displays fractal features. The Box dimension of its Rie... 详细信息

关键词： Box dimension Hausdorff dimension fractional integral fractal function

脊柱手术机器人治疗脊柱疾病的研究发展趋势及热点剖析

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中国组织工程研究 2025年第21期29卷 4612-4620页

作者：牛艳艳张琦范明星首都医科大学附属北京积水潭医院医学期刊中心北京市100035 首都医科大学附属北京积水潭医院脊柱外科北京市100035

背景:近年来在脊柱外科领域,手术机器人的应用已成为研究热点,但目前中国尚缺乏脊柱手术机器人的的文献可视化分析相关研究。目的:对脊柱手术机器人治疗脊柱疾病的研究热点进行文献可视化分析,以期为中国脊柱手术机器人的研究和发展提... 详细信息

背景:近年来在脊柱外科领域,手术机器人的应用已成为研究热点,但目前中国尚缺乏脊柱手术机器人的的文献可视化分析相关研究。目的:对脊柱手术机器人治疗脊柱疾病的研究热点进行文献可视化分析,以期为中国脊柱手术机器人的研究和发展提供有益的参考。方法:在Web of Science核心集数据库中检索脊柱手术机器人治疗脊柱疾病的相关文献,最终纳入900篇文献。采用VOSviewer 1.6.19软件对纳入文献的发文量、期刊、机构、国家、关键词、共被引文献和高被引文献进行可视化分析。结果与结论:(1)脊柱手术机器人治疗脊柱疾病研究领域的文献呈逐年上升趋势,尤其在2023年达到了发文量的高峰。美国、中国和德国是该领域的研究热点国家。中国国家自然科学基金是该领域的主要资助基金。(2)中国北京积水潭医院和美国特殊外科医院在该领域的研究具有较高的发文量。(3)《World Neurosurgery》《Spine》和《Operative Neurosurgery》是该领域的主要发文期刊。(4)关键词分析显示,研究主要集中在机器人辅助脊柱手术的准确性、微创手术、机器人脊柱手术和导航技术等方面。(5)文献共被引分析结果显示了机器人辅助技术在脊柱手术中具有显著优势,与传统手术相比,脊柱手术机器人如ROSA?Spine,ExcelsiusGPS,Mazor X及TiRobot等,具有高精度导航、精确椎弓根螺钉置入及实时反馈等优点,它们通过减少手术中X射线辐射暴露,降低患者并发症风险,提高手术成功率,显示出其在脊柱外科领域的应用前景。(6)尽管如此,相关技术的应用和精确度仍需不断积累经验以提高;机器人手术技术在降低手术辐射暴露和提高手术精度方面显示出成本效益,但还需深入探讨其在椎弓根螺钉置入过程中的精确度、手术时间影响及经济效益。(7)2021-2024年的高被引文献分析结果进一步显示,目前该领域最新研究热点主要集中在虚拟现实和增强现实技术的应用、机器人辅助椎弓根螺钉置入的准确性提升以及导航机器人脊柱手术平台的应用等。例如,通过创新技术如有机电化学神经元为脑机接口、假肢和智能软机器人技术提供了新的集成方案。同时,虚拟现实和增强现实技术在脊柱畸形矫正等领域展示了广泛应用前景。

关键词：脊柱脊柱手术机器人机器人辅助技术脊柱手术椎弓根螺钉准确性导航并发症脊柱畸形

Improving the sintering performance of blends containing Canadian specularite concentrate by modifying the binding medium

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International Journal of Minerals,Metallurgy and Materials 2018年第6期25卷 598-608页

作者： Feng zhang de-qing Zhu Jian Pan Ya-ping Mo Zheng-qi Guo School of Minerals Processing and Bioengineering Central South University Changsha 410083 China Investment Management department of Wuhan Iron and Steel Company Limited Wuhan 430083 China

Canadian specularite concentrate（CSC） possesses high total iron grade and low impurity content. However, due to the poor granulating performance and weak reactivity of CSC at high temperature, the proportion of CSC used in sintering blends is restricted. In this research, the effects of fine limonite, slake lime, and bentonite particles on the granulation performance of blends containing a high ratio of CSC were studied through granulation test. Based on the test results, the effects of modification of the binding medium on the sintering performance of blends containing a high ratio of CSC were revealed by the sintering pot test. Both the granulation property and sintering performance of blends with a high proportion of CSC were improved by modifying the binding medium.

关键词： iron ore binding medium specula^ite concentrate sintering performance

Overall water splitting over conjugated polymer photocatalysts with crystal facets modulated

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Science China Chemistry 2020年第11期63卷 1582-1583页

作者： Yu qi Fuxiang zhang State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian National Laboratory for Clean EnergyDalian 116023China

Photocatalytic overall water splitting(OWS)for H2 and O2 evolution with a 2:1 stoichiometric ratio is one of the most promising ways to convert solar energy into chemical one,but it confronts huge challenges in consideration of the uphill water oxidation with four-electron transfer[1].During the past half century,great efforts have been made to the inorganic semiconductors-based photocatalysts,and to date the maximal apparent quantum efficiency(AQE)of OWS under ultra violet(UV)light has reached over 95%,as high as that of natural photosynthesis[2].Comparatively,however,the research on water splitting using conjugated polymers or hybrid metal-organic frameworks(MOFs)for photocatalysts is still in the infancy stage,and the achievement of OWS on them is tremendously limited because of additional challenges in addressing their poor charge separation and photochemical stability[3,4].

关键词： splitting conjugated photochemical

Time-inconsistent stochastic linear quadratic control for discrete-time systems

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Science China(Information Sciences) 2017年第12期60卷 44-56页

作者： qingyuan qi Huanshui zhang School of Control Science and Engineering Shandong University

This paper is mainly concerned with the time-inconsistent stochastic linear quadratic(LQ) control problem in a more general formulation for discrete-time systems. The time-inconsistency arises from three aspects: the coefficient matrices depending on the initial pair, the terminal of the cost function involving the initial pair together with the nonlinear terms of the conditional expectation. The main contributions are: firstly,the maximum principle is derived by using variational methods, which forms a flow of forward and backward stochastic difference equations(FBSde); secondly, in the case of the system state being one-dimensional, the equilibrium control is obtained by solving the FBSde with feedback gain based on several nonsymmetric Riccati equations; finally, the necessary and sufficient solvability condition for the time-inconsistent LQ control problem is presented explicitly. The key techniques adopted are the maximum principle and the solution to the FBSde developed in this paper.

关键词： time-inconsistency open-loop equilibrium control maximum principle FBSde nonsymmetric Riccati equations

Construction and application of pre-classified smooth semi-supervised twin support vector machine

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Journal of Systems Engineering and Electronics 2019年第3期30卷 564-572页

作者： zhang Xiaodan qi Hongye School of Mathematics and Physics University of Science and Technology Beijing

In order to handle the semi-supervised problem quickly and efficiently in the twin support vector machine (TWSVM) field, a semi-supervised twin support vector machine (S2TSVM) is proposed by adding the original unlabeled samples. In S2TSVM, the addition of unlabeled samples can easily cause the classification hyper plane to deviate from the sample points. Then a centerdistance principle is proposed to pre-classify unlabeled samples, and a pre-classified S2TSVM (PS2TSVM) is proposed. Compared with S2TSVM, PS2TSVM not only improves the problem of the samples deviating from the classification hyper plane, but also improves the training speed. Then PS2TSVM is smoothed. After smoothing the model, the pre-classified smooth S2TSVM (PS3TSVM) is obtained, and its convergence is deduced. Finally, nine datasets are selected in the UCI machine learning database for comparison with other types of semi-supervised models. The experimental results show that the proposed PS3TSVM model has better classification results.

关键词： semi-supervised twin support vector machine (TWSVM) pre-classified center-distance smooth