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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1319-1324页

作者： GAO Ying LIU Di WANG Aiyang ZHANG Song he qianglong REN Shifeng FANG Jie WANG Zihan WANG Weimin State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China Jingdezhen Huaxun Special Ceramics Co.ltd. Jingdezhen 333000China Aerospace Science&Industry Defense Technology Research and Test Center Beijing 100854China

Micrometer-sized diamonds were incorporated into silicon nitride(Si_(3)N_(4))matrix to manufacture high-performance Si_(3)N_(4)-based composites using spark plasma sintering at 1500℃under 50 *** effects of the diamond content on the phase composition,microstructure,mechanical properties and thermal conductivity of the composites were *** results showed that the addition of diamond could effectively improve the hardness of the *** thermal conductivity of Si_(3)N_(4)increased to 52.97 W/m·k at the maximum with the addition of 15 wt%diamond,which was 27.5%higher than that of the monolithic Si_(3)N_(4).At this point,the fracture toughness was 7.54 MPa·m^(1/2).Due to the addition of diamond,the composite material generated a new substance,MgSiN2,which effectively combined Si_(3)N_(4)with ***2 might improve the hardness and thermal conductivity of the materials.

关键词： spark plasma sintering Si_(3)N_(4) diamond thermal conductivity mechanical properties

Fabrication and Property of SiC Ceramic with Large Thickness/Diameter Ratios

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Journal of Wuhan University of Technology(Materials Science) 2020年第3期35卷 506-513页

作者： TAN Lin he qianglong HU Lanxin TIAN Tian WANG Weimin State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness/diameter ratio on the microstructure and density of SiC ceramics was investigated in detail. The experimental results show that the addition of boron and carbon sintering aids can promote the densification process of SiC ceramic, leading to the low sintering temperature and improve mechanical properties. At 1950 ℃, SiC ceramic with a density of 99% exhibits Young's modulus, hardness, and flexural strength of 476 MPa, 28.3 GPa, and 334 MPa, respectively. It is found that long holding time has a positive effect on the uniformity of the microstructure and density distribution of SiC ceramics with large thickness/diameter ratios. Additionally, the sintering additive of boron can solid-solve into SiC, and then facilitate the phase transformation of SiC to form 6H-SiC and 4H-SiC composite ceramics.

关键词： SiC large thickness/diameter ratios mechanical properties uniformity

Microstructure,Mechanical,and Thermal Properties of B4C-TiB2-SiC Composites Prepared by Reactive Hot-pressing

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Journal of Wuhan University of Technology(Materials Science) 2020年第6期35卷 1031-1037页

作者： CAO Yaoqin he qianglong WANG Weimin China helicopter Research and Development Institute Tianjin 300450China The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

B4C-TiB2-SiC composites with excellent properties were prepared by reactive hot-pressing using B4C,TiC,and Si powders as the raw *** phase transition process was investigated by heating the powder mixture to different temperatures and combined with XRD ***2 and SiC phases were synthesized through an in situ reaction,and the mechanical and thermal properties were improved *** and mechanical properties were also studied,and the 60wt% B4C-21.6wt% TiB2-18.4wt% SiC composite showed a relative density of 99.1%,Vickers hardness of 34.6 GPa,flexural strength of 582 MPa,and fracture toughness of 5.08 MPa·m1/*** addition,the values of thermal conductivity and thermal expansion coefficient were investigated,respectively.

关键词： B4C-TiB2-SiC reactive hot pressing microstructures mechanical properties thermal properties

Fabrication of BiVO4：Effect of Structure and Morphology on Photocatalytic Activity and Its Methylene Blue Decomposition Mechanism

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Journal of Wuhan University of Technology(Materials Science) 2016年第4期31卷 791-798页

作者：郭敏娜 he qianglong wang wenjie wu jie 王为民 State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of Technology Wuhan 430070 China

BiVO4 photocatalysts were synthesized by a surfactant free hydrothermal method without any further treatments,and characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,transmission electron microscopy（TEM）,ultraviolet-visible diffuse reflectance spectroscopy（UV-vis DRS）,Raman spectroscopy,and Brunauer-Emmett-Teller（BET） surface area *** photocatalytic activity was evaluated for the degradation of the methylene blue（MB） under visible light *** from the structural and morphological characterization,it is stated that the obtained samples present monoclinic phase,and the pH value has significant influence on the *** enhanced photocatalytic performance was associated with its crystallinity,unique morphology,band gap energy,BET specific surface area,surface charge and adsorption *** recycle experiments results show that the BiVO4 photocatalysts have excellent photo-stability,and we deduced a possible mechanism by examining the effects of the active species involved in the photocatalytic process for MB photocatalytic degradation.

关键词： photocatalytic surfactant hydrothermal visible crystallinity ultraviolet irradiation Brunauer tetragonal Teller

Refinement of TiB_(2)Powders with High-speed Planetary Mill and Its Effect on TiB_(2)Sinterability

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Journal of Wuhan University of Technology(Materials Science) 2021年第3期36卷 331-337页

作者： HUANG Qiwei AI Ruomeng BAI Wenhui he qianglong WANG Aiyang HU Lanxin WANG Weimin The State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Titanium diboride ceramic was produced via spark plasma sintering(SPS)using finer TiB_(2)powder made by high-speed planetary ball *** effects of ball milling parameters on the composites and particle size of TiB_(2)powder were *** was shown that the average particle size of TiB_(2)powder decreased from 5.8 to 1.59μm and the wear rate of WC balls was 1.58 wt%,when the ball-to-powder weight ratio(BPR),the rotary speed and milling time and were 10:1,600 rpm and 20 min,*** content of WC in TiB_(2)powder can be limited below 4.58 vol%by optimizing the milling *** sintering temperature of TiB_(2)powder milled can be decreased obviously,and the mechanical properties are evidently improved and the microstructure becomes more homogeneous when the powder of TiB_(2)becomes *** relative density,hardness,bending strength,and fracture toughness of the TiB_(2)ceramic fabricated at 1700℃reach the optimal values,which are 98.13%,19.14 GPa,756 MPa,and 5.71 MPa·m~(1/2),*** decrease of TiB_(2)particle size and the introduction of WC are the potential reasons for the improvement of TiB_(2)ceramic performance.

关键词： TiB_(2)ceramic high-speed planetary ball mill particle size WC mechanical property

Ultrafine Grain Tungsten heavy Alloys with Excellent Performance Prepared by Spark Plasma Sintering

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Journal of Wuhan University of Technology(Materials Science) 2020年第2期35卷 393-398页

作者： ZHANG Jingang WANG Weimin JI Wei he qianglong WANG Aiyang TAN Lin YANG Kai State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Institute of Material Science and EngineeringWuhan University of TechnologyWuhan 430070China

Ultrafine grain tungsten heavy alloys (WHAs) were successfully produced from the nano-crystalline powders using spark plasma *** present study mainly discussed the effects of sintering temperature on the density,microstructure and mechanical properties of the *** relative density of 98.12% was obtained at 1 050 ℃,and the tungsten grain size is about 871 *** 1 000 ℃-1 200 ℃,the mechanical properties of the alloys tend to first rise and then goes *** SPS,the alloy exhibits improved hardness (84.3 HRA at 1 050 ℃) and bending strength (987.16 MPa at 1 100 ℃),due to the ultrafine-grained *** fracture mode after bending tests is mainly characterized as intergranular or intragranular fracture of W grains,interfacial debonding of W grains-binding phase and ductile tearing of binding *** EDS analysis reveals a certain proportion of solid solution between W and Ni-Fe binding *** good mechanical properties of the alloys can be attributed to grain refinement and solid solution strengthening.

关键词： tungsten heavy alloys ultrafine grain nano-crystalline powders solid solution strengthening spark plasma sintering

5XZ-10型比重式种子分选机气流孔板布置优化

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农业工程 2024年第3期14卷 65-72页

作者：程丽娟何强龙官鑫刘建明伍永福新疆工程学院控制工程学院新疆乌鲁木齐830022 内蒙古科技大学能源与环境学院内蒙古包头014010 新疆工业职业技术学院新疆乌鲁木齐830022 酒泉奥凯种子机械股份有限公司甘肃酒泉735000

种子的好坏,直接影响粮食产量,优良种子的筛选对于国家粮食安全问题具有重大意义。针对5XZ-10型比重式种子分选机筛面气流分布不均的问题进行单因素试验。利用Fluent软件,采用数值模拟与试验相结合的方法对比重式分选机气室流场进行了... 详细信息

种子的好坏,直接影响粮食产量,优良种子的筛选对于国家粮食安全问题具有重大意义。针对5XZ-10型比重式种子分选机筛面气流分布不均的问题进行单因素试验。利用Fluent软件,采用数值模拟与试验相结合的方法对比重式分选机气室流场进行了求解。为了简化计算量,引入多孔介质模型代替气流孔板。利用数值拟合求解了多孔介质模型参数,建立气室几何模型并验证了模型的可行性。将气流孔板布置高度比例系数α作为单因素变量,得到分选机空气流场及空气动力场的分布特点。为获得合理的筛面气流,讨论了不同的气流孔板高度对气室出口界面气流稳定性、均匀性的影响,发现当α=0.84时,气室出口界面气流稳定性、均匀性较好。确定气流孔板合理的安装高度530 mm,为比重式种子分选机优化设计提供了试验数据及理论依据。

关键词：种子分选机流场分布气流孔板数值模拟种业装备比重分选设备

维普期刊数据库博看期刊

5XZ-10型比重式种子分选机中离心风机流场研究

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农业工程 2024年第4期14卷 85-91页

作者：何强龙程丽娟刘建明官鑫伍永福新疆工业职业技术学院新疆乌鲁木齐830022 内蒙古科技大学能源与环境学院内蒙古包头014010 新疆工程学院控制工程学院新疆乌鲁木齐830022 酒泉奥凯种子机械股份有限公司甘肃酒泉735000

利用空气动力学原理进行种子分选,空气流场的分布至关重要。针对农业机械装置中气流均匀性问题,以5XZ-10型比重式种子分选机中离心风机为原型,利用Solidworks软件建立离心风机几何模型,运用Fluent软件对离心风机内部流场及出口流场进行... 详细信息

利用空气动力学原理进行种子分选,空气流场的分布至关重要。针对农业机械装置中气流均匀性问题,以5XZ-10型比重式种子分选机中离心风机为原型,利用Solidworks软件建立离心风机几何模型,运用Fluent软件对离心风机内部流场及出口流场进行数值模拟计算。通过仿真试验得到离心风机流场分布,对风机出口速度分布云图及矢量图结果进行分析,发现风机内部流场受到机械结构的干扰,气流在风机出口界面分布较不均匀,提出了离心风机流场优化措施,包括双叶轮双入口单出口离心风机入口增设集流器、对固定盘与叶轮的连接进行密封、风机出口采用钢板网对出口气流进行均匀性改善。在距离风机出口上方0.13 m处安装钢板网,增设钢板网后风机出口气流均匀性指数由0.88提升至0.90,提升率2.27%,解决了风机提供的气流流经5XZ-10型比重式种子分选机筛面时的均匀性问题。

关键词：离心风机流场数值模拟气流均匀性种子分选机

维普期刊数据库博看期刊

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胸椎胸骨复合型骨折的疗效分析

岭南现代临床外科 2010年第4期10卷 277-279页

作者：贺强龙汕头市潮阳区大峰医院骨科广东广州515154

目的评价胸椎胸骨复合型骨折的不同方式的治疗效果。方法对31例胸椎胸骨复合型骨折病例的治疗进行回顾性分析。31例患者均合并有多处创伤,其中胸椎压缩性骨折15例,骨折脱位11例,爆裂型骨折5例;完全性神经损伤5例,不完全神经损伤16例,无... 详细信息

目的评价胸椎胸骨复合型骨折的不同方式的治疗效果。方法对31例胸椎胸骨复合型骨折病例的治疗进行回顾性分析。31例患者均合并有多处创伤,其中胸椎压缩性骨折15例,骨折脱位11例,爆裂型骨折5例;完全性神经损伤5例,不完全神经损伤16例,无神经损伤10例。手术治疗20例(单纯胸骨手术4例,胸椎手术12例,胸椎胸骨联合手术5例),非手术治疗11人。结果随访时间0.5～5年,平均2.4年。患者均有不同程度的恢复。术后3例完全性神经损伤患者神经功能无明显改善;2例出现迟发型神经功能损害。余27例病情无加重;16例不完全神经损伤患者中3例恢复正常,9例有改善,4例无改善。结论胸骨胸椎复合型骨折多伴有神经损伤及其他多处创伤,病情复杂多变,应根据患者情况制定个体化治疗方案;早期固定胸骨有助于维持脊柱的稳定性,有效预防或延缓脊柱侧弯等疾患的发生进展。

关键词：胸椎胸骨复合型骨折

Low-Complexity Integrated Super-Resolution Sensing and Communication with Signal Decimation and Ambiguity Removal

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ZTE Communications 2024年第3期22卷 48-55页

作者： DAI qianglong ZHOU Zhiwen XIAO Zhiqiang ZENG Yong YANG Fei CheN Yan National Mobile Communications Research Laboratory Southeast UniversityNanjing 210096China Purple Mountain Laboratories Nanjing 211111China Wireless Technology Lab. 2012 LabShanghai Huawei Technolo-gies Co.LtdShanghai 201206China

Integrated sensing and communication(ISAC)is one of the main usage scenarios for 6G wireless *** most efficiently utilize the limited wireless resources,integrated super-resolution sensing and communication(ISSAC)has been recently proposed to significantly improve sensing performance with super-resolution algorithms for ISAC systems,such as the Multiple Signal Classification(MUSIC)***,traditional super-resolution sensing algorithms suffer from prohibitive computational complexity of orthogonal-frequency division multiplexing(OFDM)systems due to the large dimensions of the signals in the subcarrier and symbol *** address such issues,we propose a novel two-stage approach to reduce the computational complexity for super-resolution range estimation *** key idea of the proposed scheme is to first uniformly decimate signals in the subcarrier domain so that the computational complexity is significantly reduced without missing any target in the range ***,the decimation operation may result in range ambiguity due to pseudo peaks,which is addressed by the second stage where the total collocated subcarrier data are used to verify the detected *** with traditional MUSIC algorithms,the proposed scheme reduces computational complexity by two orders of magnitude,while maintaining the range resolution and *** results verify the effectiveness of the proposed scheme.

关键词： ISSAC sparse decimation range ambiguity two-stage approach