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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 684-692页

作者： Ya-jun Su xin-hua Liu Yong-fu Wu Hai-you Huang jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) Institute of Advanced Materials and Technology Uni- versity of Science and Technology Beijing

The steady-state temperature field of horizontal core-filling continuous casting （HCFC） for producing copper cladding aluminum rods was simulated by finite element method to investigate the effects of key processing parameters on the positions of solid-liquid interfaces （SLIs） of copper and aluminum. It is found that mandrel tube length and mean withdrawing speed have significant effects on the SLI positions of both copper and aluminum. Aluminum casting temperature （TAI）（1003-1123 K） and secondary cooling water flux （600-900 L.h-1） have little effect on the SLI of copper but cause the SLI of aluminum to move 2-4 mm. When TA1 is in a range of 1043-1123 K, the liquid aluminum can fill continuously into the pre-solidified copper tube. Based on the numerical simulation, reasonable processing parameters were determined.

关键词： metal cladding copper aluminum continuous casting interfaces computer simulation

Controllability and Its Applications to Biological Networks

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Journal of Computer Science & Technology 2019年第1期34卷 16-34页

作者： Lin Wu Min Li jian-xin Wang Fang-Xiang Wu Division of Biomedical Engineering University of SaskatchewanSaskatoonSK STN 5A9Canada School of Information Science and Engineering Central South UniversityChangsha 410083China Department of Mechanical Engineering University of SaskatchewanSaskatoonSK STN 5A9Canada

Biological elements usually exert their functions through interactions with others to form various types of biological *** ability of controlling the dynamics of biological networks is of enormous benefits to pharmaceutical and medical industry as well as scientific *** there are many mathematical methods for steering dynamic systems towards desired states,the methods are usually not feasible for applying to complex biological *** difficulties come from the lack of accurate model that can capture the dynamics of interactions between biological elements and the fact that many mathematical methods are computationally intractable for large-scale ***,a concept in control theory --controllability,has been applied to investigate the dynamics of complex *** this article, recent advances on the controllability of complex networks and applications to biological networks are *** dynamic models is the prior concern for analyzing dynamics of biological ***,we introduce a widely used dynamic model for investigating controllability of complex *** recent studies of theorems and algorithms for having complex biological networks controllable in general or specific application scenarios are ***,applications to real biological networks manifest that investigating the controllability of biological networks can shed lights on many critical physiological or medical problems,such as revealing biological mechanisms and identifying drug targets,from a systematic perspective.

关键词： biological network network controllability steering node

Ambarzumyan's Theorem for the Dirac Operator on Equilateral Tree Graphs

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 568-576页

作者： Dong-Jie WU xin-jian XU Chuan-Fu YANG Department of Mathematics School of Mathematics and StatisticsNanjing University of Science and TechnologyNanjing 210094China

The classical Ambarzumyan’s theorem states that if the Neumann eigenvalues of the Sturm-Liouville operator-d^(2)/dx^(2)+q with an integrable real-valued potential q on[0,π] are {n^(2):n≥0},then q=0 for almost all x∈[0,π].In this work,the classical Ambarzumyan’s theorem is extended to the Dirac operator on equilateral tree *** prove that if the spectrum of the Dirac operator on graphs coincides with the unperturbed case,then the potential is identically zero.

关键词： dirac operator quantum graph Ambarzumyan’s theorem inverse spectral problem

A fractal-based model for the microstructure evolution of silicon bronze wires fabricated by dieless drawing

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 770-776页

作者： Zhen Wang Xue-feng Liu Yong He jian-xin Xie Key Laboratory of the Ministry of Education of China for Advanced Processing Technology of Materials University of Science and Technology Beijing Beijing100083 China State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

The back-propagation neural （BPN） network was proposed to model the relationship between the parameters of the dieless draw- ing process and the microstrecmres of the QSi3-1 silicon bronze alloy. Combined with image processing techniques, grain sizes and grain-boundary morphologies were respectively determined by the quantitative metallographic method and the flactal theory. The outcomes obtained show that the deformed microstructures exhibit typical fractal features, and the boundaries can be characterized quantitatively by ffactal dimensions. With the temperature of 600-800℃ and the drawing speed of 0.67-1.00 mm-s-1, either a lower temperature or a higher speed will cause a smaller grain size together with an elevated fractal dimension. The developed model can be capable for forecasting the microstructure evolution with a minimum error. The average relative errors between the predicted results and the experimental values of grain size and fractal dimension are 3.9% and 0.9%, respectively.

关键词： silicon bronze dieless drawing microstructure fractal dimension neural networks

Rectifying control of wire diameter during dieless drawing by a deformation measuring method of interframe displacement

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International Journal of Minerals,Metallurgy and Materials 2012年第7期19卷 615-621页

作者： Yong He Xue-feng Liu Fang Qin jian-xin Xie Key Laboratory for Advanced Materials Processing (Ministry of Education) University of Science and Technology Beijing Beijing 100083 China

A deformation measurement method of interframe displacement was proposed in this paper. By online monitoring the shape di- mensions of both the deformation zone and its adjacent zone by machine vision, the initial and terminative positions of deformation were dynamically identified during dieless drawing, and the global monitoring and online closed-loop control of the deformation zone were achieved. The dieless drawing process was systematically carried out on NiTi shape memory alloy wires. It is shown that the deformation measurement method of interframe displacement can track the axial displacement of the wires, but this cannot be achieved by traditional machine vision. The initial and terminative positions of deformation can be accurately identified by this method. The proposed rectifying control technology can effectively decrease the wire diameter fluctuation during dieless drawing, that is, the standard deviation of the wire diameter fluctuation could be decreased fi＇om 0.30 to 0.08 mm after three passes of dieless drawing, indicating that the control system has a good rectifying ability.

关键词： wire drawing rectification deformation machine vision closed loop control systems nickel alloys sha^oe memory effect

A new insight into rapid oxidation of alloy 925 contaminated by oxide powder

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Rare Metals 2021年第7期40卷 1872-1880页

作者： He jiang jian-xin Dong Mai-Cang Zhang jiang-Yang Li Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China

Rapid oxidation takes place both in the laboratory and in industrial conditions when alloy 925 is contaminated by oxide powder,and the oxidation rate is much higher than ***,the rapid oxidation behavior and mechanism of alloy 925 were investigated by a series of comparison tests at 1160℃.It is found that the oxide powder produced during the oxidation process is mainly composed of NiCr_(2)O_(4)spinel,accompanied by NiO and NiMoO_(4).The oxide powder plays a triggering role in the rapid oxidation of alloy 925,as NiO has a strong affinity with O.A composition adjustment experiment of alloy 925 shows that rapid oxidation is the synergetic effect of Mo and Cu in the *** and Cu easily combine to form low melting point *** formation and volatilization of MoO_(3)oxide can destroy the completeness of the protective oxide *** MoO_(3)flux can dissolve protective Cr_(2)O_(3)and prevent the repair of the oxide layer and also promote the formation of nonprotective and easy-spall NiCr_(2)O_(4)*** synergetic effect of Cu and Mo in accelerating oxidation should be considered in any nickel-based alloy with a high content of Cu and Mo.

关键词： Rapid oxidation Synergetic effect Nickelbased superalloy

Microstructure and magnetic properties of sintered Nd-Fe-B magnets with Ce substitution for Nd by intergranular-alloy method

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Rare Metals 2020年第1期39卷 62-69页

作者： jian-xin Huang Ying Liu Jun Li Wei Zhao Qi Shi College of Materials Science and Engineering Sichuan UniversityChengdu610065China Key Laboratory of Advanced Special Material and Technology Ministry of EducationChengdu610065China

Aiming at the comprehensive utilization of the rare-earth resources and the preparation of the high-performance low-cost Nd-Fe-B magnets,sintered magnets with different Ce substitution amounts of 17.2 wt%,24.8 wt%and 31.8 wt%were prepared by intergranularalloy *** influence of substitution of Ce for Nd on their microstructure and magnetic properties in this work was detailedly *** results indicated that the remanence(Br)and the maximum energy product((BH)max)of the sintered magnets decreased monotonic ally with the increase in Ce ***,the obvious enhancement of coercivity(Hcj)was also observed,which was mainly due to the improvement of microstructure and the smooth,continuous grain boundary(GB).It can be found that a reasonable Ce substitution of 24.8 wt%for the sintered magnets could promote the refinement of microstructure,leading to the realization of superior magnetic *** is expected that the investigations could be beneficial to offer a feasible method for preparing the high-performance low-cost Ce-doped magnets.

关键词： Microstructure Sintered magnets Ce substitution Intergranular-alloy method

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微生物菌群调控人畜共患结核病的研究进展

动物医学进展 2025年第1期46卷 91-96页

作者：许霄峰张广智鑫婷叶建新张建伟贾丽钱佳豪温贺飞吴慧光蒋卉丁家波中国农业科学院北京畜牧兽医研究所北京100097 农业农村部动物生物安全风险预警及防控重点实验室(北方) 北京100193 扬州大学兽医学院江苏扬州225009 北京市畜牧总站北京100193 河北农业大学动物医学院河北保定071000 河北省遵化市农业农村局河北唐山064200

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具... 详细信息

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具有紧密的相关性,现已成为诸多领域中的研究热点。菌群对zTB进程的调控可通过诸多途径直接或间接地进行,如菌群稳态、代谢物及对免疫的调控等。基于此,论文综述了目前微生物菌群与zTB相关研究的最新进展,重点讨论了肠道菌群和肺部菌群与zTB的关联及调节机制,分析了肠-肺轴相互作用、菌群代谢产物对zTB的影响,探讨了通过调节宿主的菌群组成和功能对预防和辅助治疗结核病的潜在价值,旨在为zTB防控提供理论基础和借鉴。

关键词：人畜共患结核病肠道微生物菌群肠-肺轴益生菌

Microwave-assisted synthesis of some novel fluorinated pyrazolo[3,4-d]pyrimidine derivatives containing 1,3,4-thiadiazole as potential antitumor agents

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Chinese Chemical Letters 2011年第9期22卷 1036-1038页

作者： xin jian Song Yu Shao xing Gao Dong Key Laboratory of Biological Resources Protection and Utilization of Hubei Province Hubei University for Nationalities Enshi 445000 China Medical School Hubei University for Nationalities Enshi 445000 China

A facile microwave-assisted procedure for synthesis of novel fluorinated pyrazolo[3,4-d]pyrimidine derivatives containing 1,3,4-thiadiazole is described. This protocol presented such advantages as short reaction time, high yields, simple purification and environmentally benign procedures. Their antitumor activities were evaluated against HL-60 by an MTT assay. The preliminary results indicated that some title compounds exhibit more potent antitumor inhibitory activity than doxorubicin （DOX）.

关键词： Pyrazolo[3,4-d]pyrimidine 1,3,4-Thiadiazole Microwave-assisted synthesis Antitumor activity

Quantum Effects of Mesoscopic Inductance and Capacity Coupling Circuits

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Communications in Theoretical Physics 2006年第6期45卷 1126-1130页

作者： LIU jian-xin AN Zhan-Yuan SONG Yong-Hua Department of Electrical Engineering North China Electric Power University Baoding 071003 China Department of Applied Physics North China Electric Power University Baoding 071003 China Electronic and Computer Engineering Department Brunel University London UK

Using the quantum theory for a mesoscopic circuit based on the discretenes of electric charges, the finitedifference Schrodinger equation of the non-dlssipative mesoscopic inductance and capacity coupling circuit is achieved. The Coulomb blockade effect, which is caused by the discreteness of electric charges, is studied. Appropriately choose the components in the circuits, the finlte-dlfference Schrodinger equation can be divided into two Mathieu equations in representation.＂ With the WKBJ method, the currents quantum fluctuations in the ground states of the two circuits are calculated. The results show that the currents quantum zero-point fluctuations of the two circuits are exist and correlated.

关键词： mesoscopic circuit Mathieu equation quantum effect