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Effects of Rare Earth Pr/Ce on Tribological Behavior of ADC12 Alloy

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Journal of Wuhan University of Technology(Materials Science) 2021年第1期36卷 136-142页

作者： XU Lixiao YAN Hong LIU Wei xiong junjie School of Mechanical and Electrical Engineering Nanchang UniversityNanchang 330031China Key Laboratory of Light Alloy Preparation and Processing Nanchang 330031China

The microstructure and microhardness of ADC12 alloy that was mixed with 0,0.3,0.6,and 0.9 wt.% rare earth praseodymium/cerium (Pr/Ce) were *** addition of Pr/Ce improved the microhardness of the *** ADC12+0.6 wt% Pr/Ce alloy displayed the smallest grain size and maximal *** tribological behavior of the alloys was tested by the pin-on-disc dry sliding friction pair with a sliding velocity of 0.21 m/s under various loads (20,40,60,80 N).The wear morphology was observed by a scanning electron microscope (SEM) and the wear mechanism was *** result indicated that the wear resistance of ADC12+0.6 wt% Pr/Ce alloy was the most *** wear rate relative to the matrix is reduced by 67.5% under a load of 20 *** wear mechanism is adhesive wear.

关键词： Pr/Ce ADC12 microstructure microhardness wear mechanism

Precise time frequency synchronization technology for bistatic radar

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Journal of Systems Engineering and Electronics 2008年第5期19卷 929-933页

作者： Huang Yulin Yang Jianyu Wu junjie xiong Jintao School of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

A complete method of synchronization technology of bistatic radar using global position system （GPS） is presented. The pulse per second signal （1PPS） is elaborately modified to increase the time synchronization precision and keep loop locking. A very high time synchronization precision is achieved. Using the modified 1PPS to discipline the local OCXO, the reference frequency signal achieves both high long term stability （LTS） and short term stability （STS） properties. An algorithm, named phase abrupt change CFAR is presented to restrain the 1PPS phase abrupt change and keep loop locking. The experimental results indicate that this time and frequency synchronization method is effective and the time synchronization precision of the synchronization system can be improved from ±100 ns to ±25 ns. In addition, the phase noise is improved to 20 dB.

关键词： bistatic radar GPS time synchronization frequency phase synchronization.

A new latency-reducing and energy-efficient protocol for the wireless sensor network

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Frontiers of Electrical and Electronic Engineering in China 2007年第2期2卷 144-150页

作者： xiong junjie QU Yugui LIN Huahui PAN Quanke ZHAO Baohua Department of Electronic Engineering and Information Science MOEMS Key Laboratory of Multimedia Calculation and CommunicationUniversity of Science and Technology of ChinaHefei 230027China

This paper introduces a new protocol routing medium access control(RMAC)that integrates the routing and medium access control(MAC)layer *** can both reduce latency and save energy in the wireless sensor network(WSN)while most others propose protocols that sacrifice latency for *** make RMAC fit WSN better,we designed an easy and efficient routing protocol base station flooding(BSF)and then integrated it with a MAC protocol timing out MAC(TMAC)[1],while traditionally BSF and TMAC work separately at two *** call this two-layer protocol(TLP).We theoretically proved the advan-tages of RMAC over TLP and evaluated RMAC over *** simulation results show that RMAC spends half the latency of TLP,as well as consumes less energy than TLP.

关键词： WSN MAC routing energy efficient latency-reducing

A non-two-dimensional van der Waals In Se semispherical array grown by vapor-liquid-solid method for hydrogen evolution

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Chinese Chemical Letters 2023年第5期34卷 348-351页

作者： Jun Wang Tao Liang Huihui Li junjie xiong Bowen Liu Xiaohui Xu Yang Gao Zhongliang Yu Qiang Zheng Shouting Zhang Bin Wang Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of SciencesTianjin UniversityTianjin 300072China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication National Center for Nanoscience and Technology(NCNST)Beijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Two-dimensional(2D)layered materials with layer-number dependent properties are promising candidates for next-generation noble-metal-free electrocatalytic ***,the main group metal chalcogenides(MMCs)used for this purpose are rarely ***,we report the controlled growth of indium selenide(In Se)with a novel morphology(semispherical array)on a silicon substrate and its application in hydrogen evolution reaction(HER).The formation of the spherical InSe is explained with a vapor-liquid-solid growth mechanism,in which the distribution and size of the spheres could be facilely tuned by the reaction *** InSe semispherical array was demonstrated as more efficient catalyst for HER than the flake-like 2D InSe counterparts,originating from the fully exposed InSe spherical surface with abundant adsorbing sites and the high crystalline quality for electron *** work provides a controlled synthesis way of the layered In Se with a distinct spherical morphology used for the electrocatalysis applications and could be extended to other main group metal chalcogenides.

关键词： InSe Spherical array 2D materials HER Electrocatalysis

Influence of introducing Zr,Ti,Nb and Ce elements on externally solidified crystals and mechanical properties of high-pressure die-casting Al–Si alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 147-153页

作者： junjie Li Wenbo Yu Zhenyu Sun Weichen Zheng Liangwei Zhang Yanling Xue Wenning Liu Shoumei xiong Center of Materials Science and Engineering School of Mechanical and Electronic Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Traffic&Transportation Engineering Central South UniversityChangsha 410075China Shanghai Synchrotron Radiation Facility Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201204China School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

High pressure die casting(HPDC)AlSi10Mn Mg alloy castings are widely used in the automobile *** can optimize the mechanical properties of castings through heat treatment,while the release of thermal stress arouses the deformation of large integrated ***,the development of non-heat treatment Al alloys is becoming the hot *** addition,HPDC contains externally solidified crystals(ESCs),which are detrimental to the mechanical properties of *** achieve high strength and toughness of non-heat treatment die-casting Al-Si alloy,we used AlSi9Mn alloy as matrix with the introduction of Zr,Ti,Nb,and *** influences on ESCs and mechanical properties were systematically investigated through three-dimensional reconstruction and thermodynamic *** results reveal that the addition of Ti increased ESCs'size and porosity,while the introduction of Nb refined ESCs and decreased ***,large-sized Al_3(Zr,Ti)phases formed and degraded the mechanical *** introduction of Ce resulted in the poisoning effect and reduced mechanical properties.

关键词： aluminium alloy high-pressure die-casting externally solidified crystals non-heat treatment

Effect of Bi/Si Ratio of BiBSi Glass on Its Structure, Properties and Laser Sealing Shear Strength for Vacuum Glazing

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 13-24页

作者： LIU Wei JIAO Jinxu LUO Dusha ZHOU junjie SHI Lifen WANG Weiwei LI Changqing WANG Peng xiong Dehua LI Hong State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Silica-Based Materials Laboratory of Anhui Province CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China State Key Laboratory of Advanced Technology for Float Glass CNBM Research Institute for Advanced Glass Materials Group Co.LtdBengbu 233018China

The low-melting glass of Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi)system was used for the first time for laser sealing of vacuum *** the condition of constant boron content,how the structure and properties vary with Bi/Si ratio in low-melting glass was *** addition,the relationships between laser power,low-melting glass solder with different Bi/Si ratios and laser sealing shear strength were *** results show that a decrease in the Bi/Si ratio can cause a contraction of the glass network of the low-melting glass,leading to an increase of its characteristic temperature and a decrease of its coefficient of thermal *** laser sealing,the copper ions in the low-melting glass play an endothermic role.A change in the Bi/Si ratio will affect the valence state transition of the copper ions in the low-melting *** absorbance of the low-melting glass does not follow the expected correlation with the Bi/Si ratio,but shows a linear correlation with the content of divalent copper *** greater the concentration of divalent copper ions,the greater the absorbance of the low-melting glass,and the lower the laser power required for laser *** shear strength of the low melting glass solder after laser sealing was tested,and it was found that the maximum shear strength of Z1 glass sample was the highest up to 2.67 MPa.

关键词： Bi2O_(3)-B2O_(3)-SiO_(2)(BiBSi) Bi/Si ratio low-melting glass laser sealing vacuum glazing

生物酶/过硫酸铵对胍胶压裂液破胶作用机制研究

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石油钻探技术 2024年第6期52卷 126-130页

作者：熊俊杰中海油能源发展股份有限公司工程技术分公司天津300452

为有效降低胍胶压裂液破胶后产生的残渣对地层造成的伤害,通过分析不同破胶方式下胍胶压裂液破胶液分子的物理化学性质,探究了生物酶及过硫酸铵/生物酶复合破胶剂对胍胶压裂液的破胶作用机理。研究发现,与过硫酸铵破胶剂相比,生物酶及... 详细信息

为有效降低胍胶压裂液破胶后产生的残渣对地层造成的伤害,通过分析不同破胶方式下胍胶压裂液破胶液分子的物理化学性质,探究了生物酶及过硫酸铵/生物酶复合破胶剂对胍胶压裂液的破胶作用机理。研究发现,与过硫酸铵破胶剂相比,生物酶及过硫酸铵/生物酶复合破胶剂能更有效地降低破胶液的相对分子质量和分子尺寸;胍胶压裂液破胶液中的主要降解产物是二糖—五糖。胍胶压裂液破胶液残渣分析表明,残渣分子中甘露糖与半乳糖的含量比只有0.38,导致其水溶性差,这也是其存在残渣的主要原因。同时,模拟试验结果表明,注酸可以有效降解胍胶压裂液破胶液残渣含量,提高支撑剂导流能力。研究结果为破胶剂优选和降低胍胶压裂液破胶液残渣造成的伤害提供了理论依据。

关键词：胍胶压裂液破胶剂残渣支撑剂导流能力

混合稀土变质对ADC12铝合金组织及性能的影响

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材料科学与工艺 2016年第1期24卷 18-24页

作者：熊俊杰闫洪揭小平南昌大学机电工程学院南昌330031 南昌市轻合金材料制备与加工重点实验室(南昌大学) 南昌330031

为了解混合稀土Pr/Ce变质对ADC12合金组织及性能的影响,采用光学显微镜、扫描电镜、能谱分析等手段对其进行观察和分析.结果表明:当加入质量分数0.6%的Pr/Ce时,组织中粗大的初生α-Al相枝晶已变得较为细小,甚至有些α-Al晶粒变得圆整了... 详细信息

为了解混合稀土Pr/Ce变质对ADC12合金组织及性能的影响,采用光学显微镜、扫描电镜、能谱分析等手段对其进行观察和分析.结果表明:当加入质量分数0.6%的Pr/Ce时,组织中粗大的初生α-Al相枝晶已变得较为细小,甚至有些α-Al晶粒变得圆整了,富铁相则由原来的条状、块状变为颗粒状,较均匀地分布在晶粒边界上,而共晶Si相也呈细小弥散分布的颗粒状;混合稀土Pr/Ce能与该合金成分中的Al、Si、Fe、Cu 4种元素结合生成稀土金属间化合物,这些化合物在扫描电镜下呈亮白色,其形貌有针状、块状、颗粒状3种;此外,当Pr/Ce的质量分数为0.6%时,该合金具有良好的综合力学性能,其抗拉强度达到251.67 MPa,延伸率达3.04%,分别比基体合金的提高了34.91%和51.24%.

关键词： Pr/Ce 变质 ADC12合金组织和性能断口

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百兆瓦级电化学储能电站能量管理研究综述

高电压技术 2023年第1期49卷 72-84页

作者：李建林王哲曾伟熊俊杰北方工业大学储能技术工程研究中心北京100144 国网江西省电力有限公司电力科学研究院南昌330096

储能电站能量管理技术对于提高储能电站运行效率、降低全生命周期成本的重要性与日俱增。为此,首先阐述了百兆瓦级电化学储能电站相关政策、标准及发展现状;其次针对电化学储能电站的数据处理技术和通讯技术架构、应用现状进行详细分析... 详细信息

储能电站能量管理技术对于提高储能电站运行效率、降低全生命周期成本的重要性与日俱增。为此,首先阐述了百兆瓦级电化学储能电站相关政策、标准及发展现状;其次针对电化学储能电站的数据处理技术和通讯技术架构、应用现状进行详细分析;再次,对储能电站的外部需求及调度管理技术进行了归纳总结,并阐明储能系统中各电池簇级、模组级中的能量管控技术;最后对百兆瓦级电化学储能电站能量管理技术的未来工作进行了展望。

关键词：百兆瓦级电化学储能能量管理技术数据处理技术通讯技术外部调度管理技术系统内部管理技术