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Characterizing microstructure and texture after recrystallization annealing of Hi-B steel with simutaneous decarburization and nitriding

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Journal of Iron and Steel Research International 2017年第12期24卷 1215-1222页

作者： Li xiang Zhe Rong Bing Fu Hai-jun wang sheng-tao Qiu National Engineering Research Center of Continuous Casting Technology China Iron and Steel Research Institute Group School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

How to manufacture the high magnetic induction grain-oriented silicon steel（Hi-B steel）by the process featured with the primary recrystallization annealing was demonstrated,during which nitriding and decarburizing were simultaneously realized in *** the techniques of optical microscope,scanning electronic microscope and electron backscattered diffraction,both the microstructure and the texture in the samples were *** samples had been subjected to nitriding to different nitrogen contents at two specified temperatures using the two defined microstructural parameters：the grain size inhomogeneity factorσ＊and the texture factor *** former is the ratio of the mean value to standard deviation of grain sizes;the latter is the ratio of the total volume fraction of the harmful textures to that of beneficial textures including {110}〈001〉.When the N content increased from 0.0055%to 0.0330%after the annealing at both 835 and 875°C,the resultant recrystallized grain size decreased butσ＊changed little;whilst the rise of annealing temperature from 835 to 875°C resulted in the increase in both grain size andσ＊.Moreover,either the injected N content or temperature had insignificant influence on the components of primary recrystallization texture developed during ***,the increase of temperature led to the decreases in both intensity and volume fraction of{001}〈120〉and{110}〈001〉textures but increases in the{114}〈481〉andγfiber textures and the resultant decrease of AR.

关键词： Hi-B steel Simultaneous nitriding and decarburizing annealing Primary recrystallization Microstructure Texture

Microstructure and Mechanical Properties of AZ31 Mg Alloy Fabricated by Pre-compression and Frustum Shearing Extrusion

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 235-244页

作者： Kun sheng Li-Wei Lu Yao xiang Min Ma Zhong-Chang wang Hunan Provincial Key Laboratory of High Efficiency and Precision Machining of Difficult-to-Cut Material Hunan University of Science and Technology College of Materials Science and Engineering Hunan University of Science and Technology Department of Quantum Materials Science and Technology International Iberian Nanotechnology Laboratory(INL)

The AZ31 Mg alloys were processed by 6% pre-compression and frustum shearing extrusion at various temperatures, and the microstructure, texture and mechanical properties of the resulting alloys are systematically investigated. The results show that the grain size monotonically increases from 6.4 to 12.6 lm and the texture intensity increases from 6.7 to 9.6with the increase in the extrusion temperature. The combining effect of the pre-twinning and the frustum shearing deformation is found to contribute to the development of the weak basal texture in Mg alloys. The Mg alloy sheet produced at the extrusion temperature of 563 K exhibits excellent mechanical properties. The yield strength, ultimate tensile strength and elongation for the extruded alloys are 189.6 MPa, 288.4 MPa and 24.9%, respectively. Such improved mechanical properties are comparable or even superior to those of the alloys subjected to other deformation techniques, rendering the pre-compression and frustum shearing extrusion a promising way for further tailoring properties of Mg alloys.

关键词： AZ31 magnesium alloy Frustum shearing extrusion Microstructure Mechanical property Dynamic recrystallization

Ultrafine-Grained Microstructure and Improved Mechanical Behaviors of Friction Stir Welded Cu and Cu–30Zn Joints

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Acta Metallurgica Sinica(English Letters) 2018年第8期31卷 878-886页

作者： Yan-Fei wang Jian An Kun Yin Ming-Sai wang Yu-sheng Li Chong-xiang Huang School of Aeronautics and Astronautics Sichuan University Nano Structural Materials Center School of Materials Science and Engineering Nanjing University of Science and Technology

Ultra-strong joints of pure Cu and Cu–30Zn alloy were obtained by friction stir welding under flowing water. The effects of heat inputting condition and material characteristics on the morphologies, microstructures and mechanical properties of welding joints were studied. Defect-free stirring zones of pure Cu and Cu–30Zn were characterized by onion-ringed structure and plastic flowing bands, respectively. Both low stacking fault energy and fast cooling condition contributed to the formation of small recrystallized grains less than 1 μm in stirring zones. The welding joints in both materials exhibited enhanced mechanical performances due to ultrafine-grained microstructure in stirring zones and disappearance of soft heataffected-zone. The technique of digital image correlation was used to study the tensile deformation behaviors of welding joints and verify the improved tensile properties.

关键词： Friction stir welding Ultrafine grain Mechanical properties Stacking fault energy Digital image correlation(DIC)

Theoretical Studies on the Stabilities and Hydrogen Bond Actions of (H_2O)_n Clusters

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Chinese Journal of Structural Chemistry 2006年第9期25卷 1078-1084页

作者： MENG xiang-Jun wang Ke-Cheng WU Wen-sheng LI Bing-Huan wang De-Jin Department of Chemistry Tangshan Teacher＇s College Tangshan Hebei 063000 China Department of Light Industrv and Chemistry Zhaoqing University Guangdong 526061 China

The stable configurations and hydrogen bond nature of （H2O）n clusters （n = 3-6） have been investigated by the B3LYP method at the 6-31＋＋g^＊＊ level. Upon calculation, four conclusions have been drawn：（1） In the （H2O）3-5 clusters, cyclic configurations were confirmed to be the most stable. But in the （H2O）3-4 ones, only cyclic configurations could be observed. From n = 5 （（H2O）5 clusters）, three-dimensional configuration could be found：（2） In the （H2O）6 clusters, all configurations are inclined to be three-dimensional except the most stable configuration which is cyclic; （3） The stable order of （H2O）6 clusters indicates that it is the arrangement of hydrogen bond that plays a decisive role in the cluster stabilities, the zero-point energy is also important, and cluster stabilities are independent on the number of hydrogen bonds; （4） There exist strong cooperativity and superadditivity in the （H2O）n clusters.

关键词： quantum chemistry B3LYP (H2O)n clusters hydrogen bond cooperativity

Dislocation neutralizing in a self-organized array of dislocation and anti-dislocation

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Chinese Physics B 2019年第11期28卷 251-257页

作者： Feng-Lin Deng xiang-sheng Hu Shao-Feng wang Department of Physics and Institute for Structure and Function Chongqing UniversityChongqing 400030China Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China

A one-dimensional(1 D) self-organized array composed of dislocation and anti-dislocation is analytically investigated in the frame of Peierls theory. From the exact solution of the Peierls equation, it is found that there exists strong neutralizing effect that makes the Burgers vector of each individual dislocation in the equilibrium array smaller than that of an isolated dislocation. This neutralizing effect is not negligible even though dislocations are well separated. For example, when the distance between the dislocation and the anti-dislocation is as large as ten times of the dislocation width, the actual Burgers vector is only about 80% of an isolated dislocation. The neutralizing effect originates physically from the power-law asymptotic behavior that enables two dislocations interfere even though they are well separated.

关键词： dislocation array neutralizing exact solution

Gas-solid Flow Characteristics in High-density CFB

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Journal of Thermal Science 2012年第4期21卷 354-358页

作者： Xue-yao wang Bao-guo Fan sheng-dian wang xiang Xu Yun-han Xiao Research Center for Clean Energy and Power Chinese Academy of SciencesKey Laboratory of Advanced Energy and Power Chinese Academy of Sciences (Institute of Engineering Thermophysics) Beijing China

The gas-solid flow characteristics in the riser of a high density CFB of square (0.27 m×0.27 m×10.4 m) or circu-lar (? 0.187m×10.4 m) cross section, using Geldart B particles (quartz sand), was investigated experimentally. The influence of riser structure on the hydrodynamic behaviors of a high-density circulating fluidized bed was investigated. The solid circulation rate was up to 321 kg/(m2s) with the circular cross-section under the operating conditions of the main bed air velocity 12.1 m/s and loosen wind and back-feed wind flow 25.1 m3/h. Different operating conditions on realizing high density circulation was analyzed, while both solids circulation rate and particle holdup depended highly on operating conditions. The circulating gas-solid flow was accompanied by an evidently-dense character in the riser's bottom zone and became fully developed in the middle and upper zones.

关键词： HDCFB gas-solid flow solids circulation rate

Practical synthesis of methyl(E)-2-(3-(3-(2-(7-chloro-2- quinolinyl)ethenyl)phenyl)-3-oxopropyl)benzoate,a key intermediate of Montelukast

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Chinese Chemical Letters 2012年第5期23卷 518-520页

作者： Liang He Yang Hui Guo Ya Ping wang xiang Jing wang Ji Zhang Wen sheng xiang Department of Biochemical Engineering Northeast Agricultural UniversityHarbin 150030China Zhejiang Hisun Pharmaceutical Co. Ltd.Taizhou 318000China

A novel and practical synthetic route is presented for the preparation of methyl-（E）-2-（3-（3-（2-（7-chloro-2-quinolinyl）ethenyl） phenyl）-3-oxopropyl）benzoate,the key intermediate of Montelukast,a leukotriene *** main diarylpropane framework was prepared via a polarity conversation reaction resulting in an acyl anion equivalent followed by a nucleophilic substitution *** overall yield of this approach was 61%.This method is simple for operation and suitable for industrial production.

关键词： Montelukast Synthesis Intermediate Polarity conversion

甲亢患者血清血管紧张素转换酶和一氧化氮检测的相关性研究

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现代检验医学杂志 2005年第1期20卷 39-40页

作者：顾向明王胜岚黄阶胜中山市中医医院检验科广东中山528400 广东中山生物工程有限公司广东中山528437

目的探讨甲亢患者血清血管紧张素转换酶和一氧化氮的变化及它们间的相互关系。方法采用硝酸还原法、化学比色法和放免法分别检测41名甲亢患者及25名健康对照组血清一氧化氮(NO)、血管紧张素转化酶(ACE)和T3、T4的含量。结果甲亢患者血... 详细信息

目的探讨甲亢患者血清血管紧张素转换酶和一氧化氮的变化及它们间的相互关系。方法采用硝酸还原法、化学比色法和放免法分别检测41名甲亢患者及25名健康对照组血清一氧化氮(NO)、血管紧张素转化酶(ACE)和T3、T4的含量。结果甲亢患者血清NO、ACE及T3、T4含量明显高于对照组(P0.05)。甲亢患者ACE与NO含量呈正相关(r=0.264,P<0.05)。结论甲亢患者血清NO和ACE含量的变化均对其病情的观察和指导治疗有重要意义。

关键词：甲状腺功能亢进血管紧张素转化酶一氧化氮

Optimal Deployment Patterns for k-Coverage and k-Connectivity 3D WSNs in Underground Tunnel

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Journal of Electronic Science and Technology 2017年第3期15卷 303-312页

作者： wang-sheng Fang Gao-xiang Lei Zhong-Dong Hu Jin Li Faculty of Information Engineering Jiangxi University of Science and technology Ganzhou 341000

In this paper,we first model the mining structure as a arched shape in terms of the tunnel *** on the regularly placement of nodes in that model,a set of deployment patterns for seamless coverage and k-connectivity is proposed,i.e.1-and ***,we figure out the maximum horizontal distance of tangent plane to determine the placement of nodes for k-coverage（k=1,2）.Besides,the mathematical relations between the communication radius and the sensing radius are derived,when the network keeps k-coverage（k=1,2） and k-connectivity（k=2,3） under certain regularity constrains for various ***,we demonstrate the optimality of several approaches that we have proposed in the aspect of energy consumption and network lifetime.

关键词： Index Terms--Arched mine tunnel coverage,connectivity deployment patterns maximum horizontaldistance wireless sensor network (WSN).