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Development of a Non-Contact Electromagnetic Surface Velocity Sensor for Molten Metal Flow

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Journal of Iron and Steel Research International 2012年第S1期19卷 509-513页

作者： JIAN Dan-dan KARCHER Christian xu xiu-jie DENG An-yuan WANG En-gang THESS André Ilmenau University of Technology Institute of Thermodynamics and Fluid MechanicsIlmenau 100565Germany Key Laboratories on EPM Ministry of ScienceNortheastern University

During continuous casting of steel,knowledge of both direction and magnitude of the velocity at the mold surface is of special ***,the surface is covered by a non-transparent layer of mold powder to prevent formation of ***,this meniscus flow cannot be registered by optical measurement ***-contact measurement methods are of *** of such non-invasive techniques is Lorentz force veloeimetry(LFV).It is based on measuring the electromagnetically induced force acting on a magnet *** this paper we present a series of experiments that aim to demonstrate the feasibility of using two identical velocimeters,termed Time-of-Flight LFV(ToF LFV).Using ToF LFV the free-surface velocity may be purely determined by cross-correlating the two force signals delivered by the two force *** have developed a special prototype of such a measuring device termed meniscus velocity sensor(MVS).It has been designed to record local surface velocities in high-temperature metal *** Ilmenau University of Technology,the method has been successfully tested using both solid body movement and Ga^(68%)In^(20%)Sn^(12%)as a low-melting model *** the present paper we apply this technique to the case of high-temperature metal *** more detail,we present test measurements under industry-relevant conditions using both Sn^(32%)pb^(52%)Bi at 210℃ and molten steel at about 1700℃.These experiments were conducted at Key Laboratories on EPM at North Eastern *** evaluation of the data shows that our prototype of MVS works well in producing reproducible signals of which surface velocity can be determined.

关键词： free-surface liquid melt flow Lorentz force velocimetry magnetohydrodynamics

Improvement of Inner Quality of High Carbon Wire Rod Steel Using Combined Electromagnetic Stirring

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Journal of Iron and Steel Research International 2012年第S2期19卷 945-948页

作者： xu xiu-jie CHEN Feng DENG An-yuan ZHANG Xing-wu WANG En-gang He Ji-cheng Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationNortheastern University Tianjin Rockcheck Steel Group Co. LTD

To improve the quality of high carbon wire rods,combined electromagnetic stirring was introduced in the continuous casting of round billets with a diameter of 250mm at Tianjin Rockcheck Steel Group *** this paper,the positioning of final electromagnetic stirring(F-EMS)was determined by nail-shooting ***,the effect of mold electromagnetic stirring(M-EMS)on the macrostructure and internal defects in the round billets was investigated to find out the optimal operating parameters for continuous casting of SWRH 82B round *** results show the desirable positioning of F-EMS locates 9.7m below the mold level where the molten steel can be effectively driven by electromagnetic force and disperse central composition *** shrinkage cavity is totally eliminated with the rotational *** ratio and index of central composition segregation and center porosity can be reduced significantly. Furthermore,the equiaxed crystal ratio is considerably increased to 64%under 480A/3Hz M-EMS and 500A/10Hz F-EMS. Fine microstructure and mechanical property of wire rod are presented after optimization of combined electromagnetic ***,the probability of occurrence of cup-cone fracture of wire rod is reduced dramatically.

关键词： continuous casting mold electromagnetic stirring wire rod steel macrostructure nonmetallic inclusion

Differential diagnosis of isolated calf muscle vein thrombosis and gastrocnemius hematoma by high-frequency ultrasound

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Chinese Medical Journal 2013年第23期126卷 4448-4452页

作者： SU Li-ya GUO Fa-jin xu Guang HAN xiu-jie SUN Chang-kun ZHANG Zheng JING Qing-hong Department of Ultrasound Beijing Hospital of Ministry of HealthBeijing 100730 China

Background Differential diagnosis of isolated calf muscle vein thrombosis （ICMVT） and gastrocnemius hematoma is essential for early identification of deep vein thrombosis （DVT）.This study aimed to investigate the diagnostic value of high-frequency color Doppler ultrasound for differential diagnosis of ICMVT and gastrocnemius *** A retrospective case series of 35 ICMVT （M∶F,21∶14; mean age （64.5±10.6） years） and 23 gastrocnemius hematoma （M∶F,16∶7; mean age （75.4±11.8） years） patients with bilateral/unilateral lower limb pain was conducted between January 2006 and September *** and the morphology of high-frequency color Doppler ultrasonography of the lower limb deep vein,great saphenous vein,calf muscles,skin,and soft tissue were *** ICMVT hypoechoic signals were characterized by long,tube-like masses on longitudinal sections and oval masses on transverse sections,with apparent muscle thrombosis boundaries,distal and proximal venous connections,and,often,lower limb *** hematoma hypoechoic signals were characterized by large volumes,enhanced posterior hematoma echo,hyperechoic muscle boundaries,no hematoma blood flow,and no DVT,and clear differences in trauma/exercise-and oral anticoagulant-induced hematomas were readily *** to the measurement,the ratio of long diameter/transverse diameter （D/T） in ICMVT patients was about less than 2.0,whereas in gastrocnemius hematoma patients the ratio was more than *** stage isoechoic and hypoechoic signals were detected with gradually increasing ovular anechoic *** muscle fibers in the hematoma due to muscle fractures were *** High-frequency color Doppler ultrasound was found to be a sensitive and reliable method for differential diagnosis of ICMVT and gastrocnemius hematoma due to trauma and exercise or prolonged oral anticoagulant use.

关键词： high-frequency ultrasound calf venous thrombosis hematoma

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生态旅游基本特征及发展对策研究

乡镇经济 2007年第1期23卷 52-55页

作者：许秀杰安徽行政学院图书馆安徽合肥230031

当前生态旅游作为可持续旅游的一种发展模式,正在蓬勃兴起、迅速发展。本文通过对生态旅游内涵和基本特征的分析,提出生态旅游持续、健康发展的基本对策。

关键词：生态旅游特征对策

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期68卷 257-263页

作者： Jiapian Huang Chenxin Wang xu Wang Xiaoyu Zhou Wei Xiao jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

关键词： β-chiral sulfones chiral cyclic sulfinamides sulfur dioxide insertion asymmetric radical cyclization stereoselectivity

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冰冻-解冻法制备CaCO_3纳米粉体

硅酸盐通报 2008年第1期27卷 55-58,70页

作者：徐秀杰孙都成新疆大学化学化工学院乌鲁木齐830046

用无水碳酸钠和无水氯化钙为原料,以Ca^2＋-H2O-CO^2-3反应系统生成碳酸钙沉淀,按碳酸钙与水以质量比为1∶10加入蒸馏水,置冰箱中（-20℃）静态冷冻12h,取出在室温下解冻,过滤后得到样品。TEM和XRD测试结果表明：粒子基本呈球形,晶体粒... 详细信息

用无水碳酸钠和无水氯化钙为原料,以Ca^2＋-H2O-CO^2-3反应系统生成碳酸钙沉淀,按碳酸钙与水以质量比为1∶10加入蒸馏水,置冰箱中（-20℃）静态冷冻12h,取出在室温下解冻,过滤后得到样品。TEM和XRD测试结果表明：粒子基本呈球形,晶体粒径约为40～70 nm,所得产物为方解石型CaCO3。同时提出了“冰切割”机理,并对其形成进行了初步探讨,得出了冰冻-解冻制备纳米碳酸钙的新方法。

关键词：冰冻-解冻 CaCO3 纳米

Role of iron ore in enhancing gasification of iron coke:Structural evolution,influence mechanism and kinetic analysis

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 58-69页

作者： jie Wang Wei Wang xuheng Chen Junfang Bao Qiuyue Hao Heng Zheng Runsheng xu School of Chemistry and Materials Science Hubei Engineering UniversityXiaogan 432000China Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081China Institue of Ironmaking Technology Baosteel Central Research InstituteShanghai 201999China State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China

The utilization of iron coke provides a green pathway for low-carbon *** uncover the influence mechanism of iron ore on the behavior and kinetics of iron coke gasification,the effect of iron ore on the microstructure of iron coke was ***,a comparative study of the gasification reactions between iron coke and coke was conducted through non-isothermal thermogravimetric *** findings indicate that compared to coke,iron coke exhibits an augmentation in micropores and specific surface area,and the micropores further extend and *** provides more adsorption sites for CO_(2) molecules during the gasification process,resulting in a reduction in the initial gasification temperature of iron *** the heating rate in non-isothermal gasification can enhance the reactivity of iron *** metallic iron reduced from iron ore is embedded in the carbon matrix,reducing the orderliness of the carbon structure,which is primarily responsible for the heightened reactivity of the carbon *** kinetic study indicates that the random pore model can effectively represent the gasification process of iron coke due to its rich pore ***,as the proportion of iron ore increases,the activation energy for the carbon gasification gradually decreases,from 246.2 kJ/mol for coke to 192.5 kJ/mol for iron coke 15wt%.

关键词： low-carbon ironmaking iron coke gasification structural evolution kinetic model

Increased excitatory amino acid transporter 2 levels in basolateral amygdala astrocytes mediate chronic stress–induced anxiety-like behavior

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Neural Regeneration Research 2025年第6期20卷 1721-1734页

作者： Xirong xu Shoumin xuan Shuai Chen Dan Liu Qian Xiao jie Tu Shenzhen Key Laboratory of Neuroimmunomodulation for Neurological Diseases Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina CAS Key Laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina Guangdong Provincial Key Laboratory of Brain Connectome and Behavior the Brain Cognition and Brain Disease Institute(BCBDI)Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina University of Chinese of Academy of Sciences BeijingChina Faculty of Life and Health Sciences Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong ProvinceChina

The conventional perception of astrocytes as mere supportive cells within the brain has recently been called into question by empirical evidence, which has revealed their active involvement in regulating brain function and encoding behaviors associated with ***, astrocytes in the basolateral amygdala have been found to play a role in the modulation of anxiety-like behaviors triggered by chronic stress. Nevertheless, the precise molecular mechanisms by which basolateral amygdala astrocytes regulate chronic stress–induced anxiety-like behaviors remain to be fully elucidated. In this study, we found that in a mouse model of anxiety triggered by unpredictable chronic mild stress, the expression of excitatory amino acid transporter 2 was upregulated in the basolateral amygdala. Interestingly, our findings indicate that the targeted knockdown of excitatory amino acid transporter 2 specifically within the basolateral amygdala astrocytes was able to rescue the anxiety-like behavior in mice subjected to stress. Furthermore, we found that the overexpression of excitatory amino acid transporter 2 in the basolateral amygdala, whether achieved through intracranial administration of excitatory amino acid transporter 2agonists or through injection of excitatory amino acid transporter 2-overexpressing viruses with GfaABC1D promoters, evoked anxiety-like behavior in mice. Our single-nucleus RNA sequencing analysis further confirmed that chronic stress induced an upregulation of excitatory amino acid transporter 2 specifically in astrocytes in the basolateral amygdala. Moreover, through in vivo calcium signal recordings, we found that the frequency of calcium activity in the basolateral amygdala of mice subjected to chronic stress was higher compared with normal *** knocking down the expression of excitatory amino acid transporter 2 in the basolateral amygdala, the frequency of calcium activity was not significantly increased, and anxiety-like behavior was ob

关键词： anxiety astrocytes basolateral amygdala behavior dihydrokainic acid excitatory amino acid transporter 2 fiber photometry glutamate LDN-212320 transporter

在校大学生政治思想现状与“思政课”教改对策研究——以吉林省大学生为例

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吉林化工学院学报 2011年第6期28卷 3-8页

作者：许修杰吉林化工学院人文社会科学部吉林吉林132022

是在一个2004年省级教研立项完成的基础上提炼的。文章紧密结合调查结果,通过宏观和微观的统计,通过定性和定量的分析,论述了在校大学生政治思想现状,重点分析了其中存在的主要问题,并针对这些存在的问题提出了提高高校"思政课"教学效... 详细信息

是在一个2004年省级教研立项完成的基础上提炼的。文章紧密结合调查结果,通过宏观和微观的统计,通过定性和定量的分析,论述了在校大学生政治思想现状,重点分析了其中存在的主要问题,并针对这些存在的问题提出了提高高校"思政课"教学效果的改进思路。

关键词：认知趋向价值取向利益意识价值判断