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Research on semi-solid thixoforming process of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes

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Rare Metals 2005年第4期24卷 381-391页

作者： WANG Kai LIU Changming HAN Zhaotang cao jianyong ZHANG Zonghe College of Mechanical Engineering Chongqing University Chongqing 400044 China Chongqing Magnesium Industry Ltd. Co. Chongqing 401326 China

The investment on semi-solid die casting processes of AZ91D magnesium alloy brackets for generators in JH70-type motorbikes is introduced. The processes of low super-heat and cooling slope for the preparation of billets with non-dendritic microstructure, the remelting of billets for thixoforming and the parameters in the process of semi-sohd thixoforming have been researched. The results show that primary billets with non-dendritical structures can be prepared by forming great amount of nuclei in melt via the process of low super heat. By optimizing the remelting process through adjusting the current of the induced equipment, semi-solid billets with a structure of spherical grains were obtained from the primary billets with non-dendritical structure. The range of 580℃ to 583℃ is the proper remelting temperatures by which the billets have an expected thixotropy and can be transferred to a die-casting machine. The optimized parameters of semi-solid forming in a die-casting machine are as follows： the area of the ingate in the die is 383.5 mm^2, the speed of the pierce of the machine 5 m/s, the shot pressure of the pierce 75 MPa, and the maintenance pressure of the pierce 350 MPa. The castings of brackets for supporting generators in JH70 type motorbikes were formed by adopting the optimized processes and parameters mentioned above.

关键词： semi-solid thixoforming AZ91D magnesium alloy bracket motorbike

Calcium carbonate promotes the formation and stability of soil macroaggregates in mining areas of China

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Journal of Integrative Agriculture 2024年第3期23卷 1034-1047页

作者： Junyu Xie jianyong Gao Hanbing cao Jiahui Li Xiang Wang Jie Zhang Huisheng Meng Jianping Hong Tingliang Li Minggang Xu College of Resources and Environment Shanxi Agricultural UniversityTaigu 030801China Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources Taiyuan 030031China College of Land Science and Technology China Agricultural UniversityBeijing 100193China

We studied changes in the concentrations of aggregate-cementing agents after different reclamation times and with different fertilization regimes,as well as the formation mechanism of aggregates in reclaimed soil,to provide a theoretical basis for rapid reclamation of soil fertility in the subsidence area of coal mines in Shanxi Province,*** this study,soil samples of 0–20 cm depth were collected from four fertilization treatments of a longterm experiment started in 2008:no fertilizer (CK),inorganic fertilizer (NPK),chicken manure compost (M),and50%inorganic fertilizer plus 50%chicken manure compost (MNPK).The concentrations of cementing agents and changes in soil aggregate size distribution and stability were *** results showed that the formation of>2 mm aggregates,the aggregate mean weight diameter (MWD),and the proportion of>0.25 mm water-stable aggregates (WR_(0.25)) increased significantly after 6 and 11 years of *** concentration of organic cementing agents tended to increase with reclamation time,whereas free iron oxide (Fed) and free aluminium oxide(Ald) concentrations initially increased but then *** general,the MNPK treatment signi?cantly increased the concentrations of organic cementing agents and CaCO_(3),and CaCO_(3) increased by 60.4%at 11 years after ***,CaCO_(3) had the greatest effect on the stability of aggregates,promoting the formation of>0.25 mm aggregates and accounting for 54.4%of the variance in the proportion and stability of the *** was concluded that long-term reclamation is bene?cial for improving soil *** MNPK treatment was the most effective measure for increasing maize grain yield and concentration of organic cementing agents and CaCO_(3).

关键词： reclamation time manure combined with inorganic fertilizer soil aggregate stability cementing agents CaCO_(3)

Observation of Multiple Broadband Alfvénic Chirping Modes in HL-2A NBI Plasmas

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Chinese Physics Letters 2021年第5期38卷 41-45页

作者： Liming Yu Wei Chen Xiaoquan Ji Peiwan Shi Xuantong Ding Zhongbing Shi Ruirui Ma Yumei Hou Yonggao Li Jiaxian Li jianyong cao Wulyu Zhong Min Xu Xuru Duan Southwestern Institute of Physics Chengdu 610041China Key Laboratory of Materials Modification by Laser Ion and Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China

Multiple broadband Alfvenic chirping modes(CMs),with frequencies in the wide range of f-35-150 kHz and chirping down rapidly,are found in HL-2A neutral beam injection plasmas,and the CMs can even *** frequency chirping down process can be completed within-1 ms,and the frequency shift can reach 30-50 *** CMs propagate in ion diamagnetic drift directions *** toroidal mode number is confirmed to be n=1,2,3 and 4 for the f-35-65,55-90,70-120 and 100-150 kHz CMs,*** CMs are more like to be energetic-particle continuum modes(EPMs),since the modes almost locate on the Alfven continuum.

关键词： kHz Observation of Multiple Broadband Alfv nic Chirping Modes in HL-2A NBI Plasmas NBI

Microwave Reflectometry on HL-2A Tokamak

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Southwestern Institute of Physics Annual Report

Southwestern Institute of Physics Annual Report 2005年第1期 32-34页

作者： LIU Zetian XIAO Weiwen DING Xuantong cao jianyong SHI Zhongbing LI Yingliang LU Jie LUO Cuiwen

One of the most important electron density diagnostics, microwave reflectometry, has been developed on many large and medium nuclear fusion devices in recent years . Not only the electron density profiles with high temporal and spatial resolutions, but also the profiles of plasma rotation and turbulence can be obtained with this diagnostic system.

关键词： Microwave scanning frequency RF modulation reflection and receiver

Particle Confinement Improvement by Current Ramp on the HL-1M Tokamak

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中国核科技报告 2002年 885-888页

作者： YAN Longwen WANG Enyao LIU Yong QIAN Jun CHEN Liaoyuan TIAN Peihong ZHOU Yan cao jianyong YAO Lianghua

The scaling laws of energy confinement are very significant for confinement improvement. A typical scaling law of ohmic heating with low effective charge and radiation power is given by Goldston[1]

关键词： Particle confinement Current ramp Energy confinement

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列阵平顶光束大气传输的热晕效应

光学学报 2019年第1期39卷 278-283页

作者：李晓庆曹建勇丁洲林季小玲四川师范大学物理与电子工程学院四川成都610101 四川大学物理科学与技术学院四川成都610064

研究了热晕效应对相干合成和非相干合成的列阵平顶光束在大气中传输的影响。结果表明:当列阵平顶光束在大气中传输且存在横向风时,光斑呈月牙状;相干合成时,光斑内存在多个光强峰值;非相干合成时,光斑内始终保持一个峰值;相对于列阵平... 详细信息

研究了热晕效应对相干合成和非相干合成的列阵平顶光束在大气中传输的影响。结果表明:当列阵平顶光束在大气中传输且存在横向风时,光斑呈月牙状;相干合成时,光斑内存在多个光强峰值;非相干合成时,光斑内始终保持一个峰值;相对于列阵平顶光束的相干合成,非相干合成受热晕的影响较小;光束阶数N越大的列阵平顶光束受热晕的影响越小,即相对于列阵平顶光束,列阵高斯光束(N=1)受热晕的影响更大;光束传输效率在自由空间中随着N的增大而减小,在大气中则随着N的增大而增大;在大气中且功率相同时,列阵平顶光束的传输效率优于列阵高斯光束的传输效率。

关键词：物理光学大气光学热晕效应列阵平顶光束相干合成非相干合成

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轿车副车架的路谱试验及可靠性分析

工程与试验 2012年第2期52卷 20-22,76页

作者：曹建永国家机动车产品质量监督检验中心(上海) 上海201805

相对电子产品可靠性试验而言,机械产品可靠性试验理论问题还处于不成熟的阶段。本文对机械可靠性试验做了简单的介绍,依据某车型副车架的受力分析,通过建立有效的试验台架,合理设计试验方案,对试验数据进行可靠性分析,给出改进方法,对... 详细信息

相对电子产品可靠性试验而言,机械产品可靠性试验理论问题还处于不成熟的阶段。本文对机械可靠性试验做了简单的介绍,依据某车型副车架的受力分析,通过建立有效的试验台架,合理设计试验方案,对试验数据进行可靠性分析,给出改进方法,对副车架优化分析,从而阐述可靠性试验在汽车零部件检验中的应用。

关键词：可靠性加速试验统计分析疲劳寿命

基于TiH_2粉末短流程制备高性能钛的研究

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材料研究学报 2016年第10期30卷 737-744页

作者：肖平安陈超曹杰义宋建勇李志华湖南大学材料科学与工程学院长沙410082

以极细TiH_2粉末为原料,采用压制/真空烧结的方法制备细晶或者超细晶钛,并通过HIP进一步提高钛的致密度以保障力学性能;同时还研究了添加少量Y对钛制品的影响。通过拉伸试验评价了所得钛制品的力学行为,并对显微组织和断口开展了系统分... 详细信息

以极细TiH_2粉末为原料,采用压制/真空烧结的方法制备细晶或者超细晶钛,并通过HIP进一步提高钛的致密度以保障力学性能;同时还研究了添加少量Y对钛制品的影响。通过拉伸试验评价了所得钛制品的力学行为,并对显微组织和断口开展了系统分析。研究结果表明,由极细TiH_2粉末分解而来的钛粉具有优秀的烧结性能,在600~900℃发生快速致密化,当烧结温度≥1000℃时制品的相对致密度〉97%。随着烧结温度的提高,制品的晶粒逐步长大,但是在1150℃下真空烧结2 h后平均晶粒度仍然小于10 mm。拉伸试验结果表明,纯钛制品的抗拉强度在700~1032 MPa之间,而含Y钛制品的抗拉强度〉750 MPa,且延伸率为8%~10%。TiH_2分解对所获Ti粉起始晶粒度的遗传性影响和钛粉中固溶态H对晶粒合并长大的阻碍作用,是利用极细TiH_2粉末短流程制备细晶或者超细晶钛的机理。

关键词：金属材料氢化钛钛超细晶力学性能

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高危妊娠孕产妇相关危险因素分析

中国实用护理杂志 2019年第13期35卷 961-964页

作者：王建英陈瑶陈芳曹建用中山大学附属第五医院产科珠海519000

目的分析高危妊娠的高危因素、可转变因素转归率及妊娠结局,总结高危妊娠管理经验,使其合理化,规范化,提高孕妇和围生儿的健康,保障母婴安全。方法将2016年1月至2017年3月进行产检的6472例孕妇,根据高危妊娠相关管理办法及实施细则进行... 详细信息

目的分析高危妊娠的高危因素、可转变因素转归率及妊娠结局,总结高危妊娠管理经验,使其合理化,规范化,提高孕妇和围生儿的健康,保障母婴安全。方法将2016年1月至2017年3月进行产检的6472例孕妇,根据高危妊娠相关管理办法及实施细则进行高危因素筛查,并对高危孕妇进行系统管理。结果1610例高危妊娠孕妇,≥3种高危因素者163例占10.12%,2种高危因素者391例占24.29%,1种高危因素者1056例占65.59%;前5位高危因素为流产史、年龄、妊娠高血压或轻度子痫前期、先兆早产和34周以上的孕妇胎膜早破;高危妊娠孕妇中,19~25岁249例占11.29%;26~30岁441例占18.27%;31~34岁536例占36.49%;≥35岁384例占23.85%。可转变危险因素妊娠高血压、先兆早产、内分泌疾病和产前出血,转正常率分别为32.77%占58/177、83.21%(109/131)、46.88%(45/96)和83.13%(69/83);剖宫产率最高的年龄段为≥35岁的孕产妇,随年龄的减少,剖宫产率逐渐下降;阴道助产率最高的年龄组为31~34岁高危妊娠孕产妇,但各组差异不多;围生儿死亡率最高的为≥35岁的孕产妇(χ^2=24.989、4.189、4.344,P<0.05)。≥35岁的孕产妇发生子痫、产褥感染和产后出血的风险均明显高于其他年龄的孕产妇,差异有统计学意义(χ^2=10.823、14.594、25.306,P<0.05)。结论高危妊娠的影响因素较多,对影响因素进行筛查、识别和管理,重视健康教育,促进医院管理和社区管理合作,加强高危妊娠的管理,有助于降低高危孕产妇严重不良妊娠结局,改善母婴预后。

关键词：高危妊娠高危因素管理效果