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Shear Model of Metal Melt Flowing on Vibration Wall and Effect of Shear Stress on Solidification Microstructure

Acta Metallurgica Sinica(English Letters) 2018年第6期31卷 650-658页

作者： ren-Guo Guan xiang Wang Ying-Qiu Shang Di Tie Run-Ze Chao School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China School of Materials Science and Engineering Northeastern University Shenyang 110819 China Luoyang Ship Material Research Institute Luoyang 471000China

In this work,the shear model of metal melt flowing on vibration surface is established,and coupling effects of vibration and shear on the distribution of shear stress in melt and melt solidification microstructure are *** results show that the transition of melt from laminar flow to turbulent flow occurs earlier with increasing vibration frequency and vibration *** the laminar flow melt,shear stress in melt decreases with increasing vertical length,but it decreases firstly and then stabilizes with increasing flow *** the turbulent flow melt,shear stress decreases firstly and then stabilizes with increasing vertical length,but it increases with increasing flow *** the increase in vibration frequency and amplitude,shear stress along flow direction in laminar flow melt increases,while shear stresses along both flow direction and vertical direction in turbulent flow melt *** stress in melt decreases with increasing length along vertical *** the increase in flow length,shear stress decreases firstly and then stabilizes in laminar flow melt,while it increases in turbulent flow *** the increase in vibration frequency and amplitude,shear stress increases in laminar flow melt,while it stabilizes in turbulent flow *** on theoretical calculation,the maximum shear stress in melt during vibration shear flow is always much lower than the yield strength of a-Al grain,so the shear stress induced by vibration shear flow cannot break columnar crystal,which agrees with the experiment ***,the model can explain the shear constitutive relation of melt flow on vibration surface relatively well.

关键词： Solidification Flow near surface Shear Vibration Columnar crystal

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Coordinate Transformation and Exact Solutions of Schrodinger Equation with Position-Dependent Effective Mass

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Communications in Theoretical Physics 2007年第6期47卷 1001-1009页

作者： JU Guo-Xing CAI Chang-Ying xiang Yang ren Zhong-Zhou Department of Physics Nanjing University Nanjing 210093 China Department of Physics Jinggangshan University Ji＇an 343009 China Center of Theoretical Nuclear Physics National Laboratory of Heavy-Ion Accelerator Lanzhou 730000 China

Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The eigenfunctions can be expressed in terms of the Jacobi, Hermite, and generalized Laguerre polynomials. All potentials for these solvable systems have an extra term Vm, which is produced from the dependence of mass on the position, compared with those for the systems of constant mass. The properties of Vm for several mass functions are discussed.

关键词： coordinate transformation Schrodinger equation position-dependent mass eigenfunction special functions

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Enzyme Activity in Water-Stable Soil Aggregates as Affected by Long-Term Application of Organic Manure and Chemical Fertiliser

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Pedosphere 2013年第1期23卷 111-119页

作者： LIU Yi-ren LI xiang SHEN Qi-Rong XU Yang-Chun Jiangsu Provincial Key Laboratory for Solid Organic Waste Utilization College of Resources and Environmental SciencesNanjing Agricultural University Institute of Soil Fertilizer and Resource Environment Jiangxi Academy of Agricultural Sciences

The activities of invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase in different fractions of waterstable aggregates (WSA) were examined in long-term (26 years) fertilised soils. The long-term application of organic manure (OM) with chemical fertiliser (CF) significantly increased macroaggregate and decreased microaggregate percentages, enhanced the mean weight diameter, and significantly increased soil total carbon (TC) and total nitrogen (TN) contents of WSA in different size fractions. Combined fertilisation with OM and CF also increased invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase activities of WSA in different size fractions. Enzyme activities were higher in macroaggregates than in microaggregates. The distribution of enzyme activities generally followed the distribution of TC and TN in WSA. The geometric mean of the enzyme activities in different WSA of OM-treated soils was significantly higher than that in soils treated with 100% CF or no fertiliser. The results indicated that the long-term combined application of OM with CF increased the aggregate stability and enzyme activity of different WSA sizes, and consequently, improved soil physical structure and increased soil microbial activity.

关键词： distribution mean weight diameter stability total carbon total nitrogen

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Effect of Transverse Static Magnetic Field on Droplets Transient and Inclusions Evolution During the Electroslag Remelting Process of GCr15 Ingots

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Acta Metallurgica Sinica(English Letters) 2018年第12期31卷 1311-1316页

作者： Qiang Li Yun-Bo Zhong Chu-Xiong Sun Huai Wang Tian-xiang Zheng Wei-Li ren Zhong-Ming ren State Key Laboratory of Advanced Special Steels Shanghai University

The voltage was recorded to investigate the influence of the static magnetic field on droplet evolution during the mag-netically controlled electroslag remelting （MC-ESR） process. MC-ESR experiments were carried out under differentremelting current, and transverse static magnetic fields （TSMF） of 85 mT, 130 mT and 160 mT were *** work was performed to obtain the quantitative data of the droplets. The ASPEX Explorer was utilized toinvestigate the inclusions evolution of GCr15 ingots. The number of the droplets was 31 in 20 s during the traditional ESRprocess and reached 50 and 51 under the MC-ESR process with the TSMF of 85 mT and 130 mT, respectively. Whencompared the traditional ESR process with the MC-ESR process, the inclusions amount reduced 67%.

关键词： Electroslag remelting Static magnetic field Droplet transient Inclusions evolution Electromagnetic vibration effect

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Combined lumbar muscle block and perioperative comprehensive patient-controlled intravenous analgesia with butorphanol in gynecological endoscopic surgery

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World Journal of Clinical Cases 2021年第34期9卷 10540-10548页

作者： Rong-Yu Zhu Si-Qu xiang Dou-ren Chen Department of Anesthesiology Central Hospital of Enshi Tujia and Miao Autonomous PrefectureEnshi 445000Hubei ProvinceChina Department of Pharmacy Huai’an Hospital Affiliated to Xuzhou Medical UniversityHuai’an 223002Jiangsu ProvinceChina

BACKGROUND Laparoscopic surgery has become a common surgical approach for the clinical treatment of intra-abdominal lesions in recent *** hypothesized that lumbar block with postoperative patient-controlled intravenous analgesia(PCIA)by butorphanol after gynecological surgery under general anesthesia would be more effective than PCIA by butorphanol *** To investigate the effect of lumbar block with PCIA by butorphanol after gynecological surgery under general *** This study assessed 120 women scheduled for laparoscopic surgery at our hospital between May 2017 and May *** were divided using a random number table into a research group(those who received quadratus lumborum block combined with PCIA analgesia by butorphanol)and a control group(those who received only PCIA analgesia by butorphanol),with 60 patients in each *** factors,visual analog scale scores for pain,serum inflammatory markers,PCIA compressions,Ramsay scores,and adverse events were compared between groups using a t-test,analysis of variance,orχ2 test,as *** There were no significant differences in demographic factors between groups(all P>0.05).The visual analog scale scores of the research group in the resting state 12 h and 24 h postoperatively were significantly lower than those of the control group(Prences in the levels of serum tumor necrosis factor-α,interleukin(IL)-6,or IL-8 between groups(P>0.05).The serum tumor necrosis factor-αlevels of the research group 24 h postoperatively were significantly lower than those of the control group(P<0.05).The levels of serum IL-6 and IL-8 in the study group 24 h and 48 h postoperatively were significantly lower than those in the control group(P<0.05).CONCLUSION Lumbar block with PCIA with butorphanol after gynecological surgery under general anesthesia significantly improves the analgesic effect and reduces the degree of inflammation,ins

关键词： Quadratus lumborum block Butorphanol Patient-controlled intravenous analgesia Analgesic effect

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Energy-balanced unequal clustering protocol for wireless sensor networks

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The Journal of China Universities of Posts and Telecommunications 2010年第4期17卷 94-99页

作者： JIANG Chang-jiang SHI Wei-ren xiang min tanG Xian-lun College of Automation Chongqing University Chongqing 400044 China College of Automation Chongqing University of Posts and Telecommunications Chongqing 400065 China

Clustering provides an effective way to prolong the lifetime of wireless sensor networks. One of the major issues of a clustering protocol is selecting an optimal group of sensor nodes as the cluster heads to divide the network. Another is the mode of inter-cluster communication. In this paper, an energy-balanced unequal clustering （EBUC） protocol is proposed and evaluated. By using the particle swarm optimization （PSO） algorithm, EBUC partitions all nodes into clusters of unequal size, in which the clusters closer to the base station have smaller size. The cluster heads of these clusters can preserve some more energy for the inter-cluster relay traffic and the ＇hot-spots＇ problem can be avoided. For inter-cluster communication, EBUC adopts an energy-aware multihop routing to reduce the energy consumption of the cluster heads. Simulation results demonstrate that the protocol can efficiently decrease the dead speed of the nodes and prolong the network lifetime.

关键词： wireless sensor networks clustering protocol PSO algorithm multihop routing

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A Novel Diamine,4'-Phenyiphenyi 4-(3",5"-Diaminobenzoyioxy)-benzoate and Longer Side-chain Polyimide

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Chinese Chemical Letters 2005年第9期16卷 1151-1154页

作者： Jin YANG Li Gang ren xiang Yang LIU Yi GU State Key Laboratory of Polymeric Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065

This is a part of our systematic research work on polyimides with mesogenic unit side chain. In this study, a new 4＇-phenylpbenyl 4-（3＂,5＂-diaminobenzoyloxy）benzoate and polyimide were synthesized, and characterized by FTIR, ^1H-NMR, inherent viscosity, mechanical properties, and solubility measurements. The diamine composed with mesogenic unit aryl ester groups and bipbenyl group with longer L/D ratio, was synthesized by two key steps. Firstly, the hydroxy group of 4-hydroxybenzoic acid was protected by acetoxy group for avoiding self- polymerization of 4-hydroxybenzoic acid, and then selectively hydrolyzed after esterification of carboxyl. Secondly, a selective catalysis hydrogenation was adopted to prevent the aryl ester from deoxidation. Based on this diamine, a novel polyimide was prepared by polycondensation of 4＇-phenylphenyl 4-（3＂, 5＂-diaminobenzoyloxy）benzoate and 4-aminophenyl ether（ODA） with 4, 4＇-oxydiphthalic anhydride（ODPA） in N-methyl-2-pyrrolidone （NMP）. The resulting polyimide with longer side chain showed better solubility and more regular structure. Its inherent viscosity is lower than that without side chains, but its modulus and strength not only maintained, even improved.

关键词： Polyimide film materials side-chain synthesis

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Evolution of Al2O3 inclusions by cerium treatment in low carbon high manganese steel

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Journal of Iron and Steel Research International 2017年第9期24卷 925-934页

作者： Hao Li Yan-chong Yu xiang ren Shao-hua Zhang She-bin Wang College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024ShanxiChina

The influence of cerium（Ce）treatment on the morphologies,size and distributions of Al_2O_3 inclusions in low carbon high manganese steel was investigated by OM,SEM-EDS and theoretical *** results showed that Ce can modify the morphologies and types of Al_2O_3 *** Ce treatment,the irregular Al_2O_3 inclusions were replaced by smaller and dispersive spherical cerium *** effects of treatment time and Ce content on the evolution of Al_2O_3 inclusions were *** indicated that Al_2O_3 inclusions were wrapped by rare earth inclusions to form a ring like shape Ce-enriched band around the *** was established to elucidate the evolution mechanism of Al_2O_3 *** kinetics of inclusions was discussed qualitatively to analyze the velocity controlled *** was found that diffusion of Ce^（3＋）and Al^（3＋）in solid inclusion core and the formed intermediate layer would be the limited step during the evolution process.

关键词： Low carbon high manganese steel Inclusion Cerium treatment Evolution mechanism Transferring kinetics

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Impacts of the stratospheric quasi-biennial oscillation on the tropospheric circulation and climate in the Northeast Asia-North Pacific region in early summer

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Atmospheric and Oceanic Science Letters 2023年第3期16卷 14-19页

作者： xiang Gao Jinggao Hu Rongcai ren Yifan Shen Key Laboratory of Meteorological Disaster Ministry of Education(KLME)/Joint International Research Laboratory of Climate and Environmental Change(ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science and TechnologyNanjingChina State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina

本文研究了平流层准两年振荡(QBO)对东北亚-北太平洋地区初夏对流层环流和地表气温的影响.在QBO西风位相年,东北亚至北太平洋地区存在一支由QBO引发的平均经向环流异常,该经向环流异常可在东北亚至北太平洋地区激发正涡度,并形成异常气... 详细信息

本文研究了平流层准两年振荡(QBO)对东北亚-北太平洋地区初夏对流层环流和地表气温的影响.在QBO西风位相年,东北亚至北太平洋地区存在一支由QBO引发的平均经向环流异常,该经向环流异常可在东北亚至北太平洋地区激发正涡度,并形成异常气旋式环流.气旋左侧出现的异常偏北风导致6月东北亚地表气温下降.QBO东风位相年的结果与西风位相年大致相反.这些结果为QBO对热带外地区天气,气候的影响提供了新的证据,并为东北亚初夏地表气温的预测提供了新的线索。

关键词：平流层准两年振荡平均经向环流初夏时期地表气温热带外对流层

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BTC-Shadow: an analysis and visualization system for exposing implicit behaviors in Bitcoin transaction graphs

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Frontiers of Computer Science 2023年第6期17卷 167-169页

作者： Ding BAO Wei ren Yuexin xiang Weimao LIU Tianqing ZHU Yi ren Kim-Kwang Raymond CHOO School of Computer Science China University of GeosciencesWuhan 430074China Hubei Key Laboratory of Intelligent Geo-Information Processing Wuhan 430074China NSFOCUS Technologies Group Co. Ltd.Beijing 100089China School of Computing Sciences University of East AngliaNorwich NR47TJUK Department of Information Systems and Cyber Security University of Texas at San AntonioSan AntonioTX 78249-0631USA

1 Introduction A Bitcoin ledger comprises a sizable number of transaction records,which can be utilized to make it easier to track and analyze the traits and patterns of cryptocurrency-related *** facilitate the visual analysis of Bitcoin,numerous tools with various aims have been *** example,MiningVis[1]and SuPoolVisor[2]are the analytics systems for Bitcoin mining pools,as well as[3-5]focus on the Bitcoin transaction graphs ***,due to our previous research requirements for Bitcoin transaction graphs,none of the available tools can provide exploring the features of connection related to the address and observe significant visual ***,using these tools is challenging to navigate to abnormal node clusters effortlessly from large node groups and then analyze the local interlink characteristics between transaction nodes with interactive analytics.

关键词： analytic implicit utilized

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