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microstructure and mechanical Properties of Backward-extruded mg-Zn-xCa Biomaterials

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Microstructure and Mechanical Properties of Backward-extrude...

中国材料大会2012

作者： Xuejun Li Hui Li Shuangshuang Zhao Ning ma Qiuming Peng State Key Laboratory of metastable materials Science and Technology Yanshan University

ISBN: (纸本)9783037856086

The mg-1.0Zn-xCa （x=0.2, 0.5, 0.8, 1 wt. %） alloys were prepared by zone solidification and backward extrusion technology. The microstructure and mechanical properties of backward-extruded mg-1.0Zn-xCa alloys were investigated. The results showed that these backward-extruded mg-1.0Zn-xCa alloys were mainly composed of equi-axed pentagon-shaped grains and some mg0.9Zn0.03 precipitates. The tensile and compressive strengths of backward-extruded mg-1.0Zn-xCa alloys were greatly improved. The improved mechanical properties are mostly attributed to fine grain strengthening, solid solution strengthening and precipitate strengthening. The results demonstrated that the micro alloying of Ca element was one of effective method to improve the mechanical properties of mg-1.0Zn based biomaterials.

关键词： mg-1.0Zn-xCa alloys Backward extrusion

Seasonal variation of the ion upflow in the topside ionosphere during Subauroral Polarization Streams periods

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Seasonal variation of the ion upflow in the topside ionosphe...

中国空间科学学会空间物理学专业委员会第十五届全国日地空间物理学研讨会

作者： H.Wang S.Y.ma H.Luehr Dept.of Space Physics School of Electronic InformationWuhan University Helmholtz Centre Potsdam-GFZ German Research Center for GeosciencesD-14473 PotsdamGermany

A statistical study has been performed by using two years of DmSP plasma observations to investigate the seasonal effect of SAPS(Subauroral Polarization Streams)on the ion upflow in the duskside ionosphere in the Northern *** are obvious upflows occurring in the topside ionosphere around the SAPS region,exceeding 200 m/s at winter solstice,indicating the important effect of SAPS on the local plasma upward *** SAPS and ion upward velocity show similar seasonal variations,largest in winter and smallest in summer,irrespective of geomagnetic activities.A good correlation is found and a linear relationship is derived between SAPS and the ion upflow *** ion temperature drops down around the SAPS region,which can be explained by the cooler gas ahead of the upwelling hot ion gas due to the frictional *** electron temperature elevates around the SAPS region due to the energy input from the inner *** the ion and electron temperatures are higher in summer than in winter,except for Kp≥4 when the winter and summer electron temperatures are quite *** present work highlights the important role of the SAPS related frictional heating at mid latitudes in the local formation of the strong upward flow,which might provide a direct ionospheric ion source for the plasmasphere in the duskside subauroral region.

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限制定向凝固法制备YBCO超导体单畴生长的分析

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稀有金属材料与工程 2007年第1期36卷 166-169页

作者：曹海涛胡锐寇宏超马丽马晓勇高恩志周廉西北工业大学陕西西安710072

采用定向凝固技术可获得高临界电流密度的YBCO样品。本文研究了YBCO试样在定向凝固过程的融化生长阶段所出现的停止生长现象,并分析了YBCO块材生长前沿的形态和化学成分。结果表明:当生长前沿液相中Y和Ba消耗殆尽而富Cu时,YBCO晶体的生... 详细信息

采用定向凝固技术可获得高临界电流密度的YBCO样品。本文研究了YBCO试样在定向凝固过程的融化生长阶段所出现的停止生长现象,并分析了YBCO块材生长前沿的形态和化学成分。结果表明:当生长前沿液相中Y和Ba消耗殆尽而富Cu时,YBCO晶体的生长就会停止;为连续生长具有一定取向的YBCO样品或大块YBCO超导体,需要将融化生长过程中生长前沿的液相成分调整为富Y和Ba的成分。

关键词：定向凝固 YBCO 超导单畴

阳洼流域土壤137Cs的空间分布及侵蚀研究

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水土保持通报 2008年第2期28卷 27-30,F0002页

作者：马远远马琨马斌徐志友卜崇德宁夏大学农学院银川宁夏750021 宁夏水利厅水土保持局银川宁夏750001

利用137Cs示踪技术,研究了宁南黄土高原阳洼流域土壤137Cs的空间分布和侵蚀特征。研究结果表明,流域137Cs背景值为1966.99Bq/m2,流域内不同土地利用方式下土壤137Cs比活度不同,且有比较明显的137Cs比活度分异。流域内林草地土壤剖面137C... 详细信息

利用137Cs示踪技术,研究了宁南黄土高原阳洼流域土壤137Cs的空间分布和侵蚀特征。研究结果表明,流域137Cs背景值为1966.99Bq/m2,流域内不同土地利用方式下土壤137Cs比活度不同,且有比较明显的137Cs比活度分异。流域内林草地土壤剖面137Cs呈现指数分布模式,坡耕地剖面的137Cs则呈均匀分布模式。不同土地利用方式下土壤137Cs的面积活度表现为沟台>林草地>农耕坡地,其中农耕坡地、沟台地土壤侵蚀、沉积表现出较大的变异,变异系数达65%以上。阳洼流域土壤侵蚀模数与137Cs比活度呈现出相反的分布趋势,但都明显具有斑块状和条带状分布的特点。流域土壤以中、强度侵蚀为主,中、强度侵蚀面积占流域总面积的46%,在流域土壤侵蚀防治中坡耕地仍是治理的关键。

关键词：空间分布137Cs 土壤侵蚀阳洼流域

Scaffold-regulation buffered moS_(2)anode kinetics for high-performance Na-/K-ion storage

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Journal of materials Science & Technology 2023年第14期145卷 14-24页

作者： Tuzhi Xiong Xincheng Yao David Adekoya Hao Yang m-Sadeeq Balogun College of materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082China Centre for Clean Environment and Energy Griffith School of EnvironmentGold Coast CampusGriffith UniversityQLD4222Australia Guangxi Key Laboratory of Electrochemical Energy materials School of Chemistry&Chemical EngineeringGuangxi UniversityNanning 530004China

Designing a highly conductive scaffold with unique function has great significance in elevating the stor-age properties of molybdenum sulfide(moS_(2))for sodium-and potassium-ion ***,we show that forming a three-dimensional(3D)highly conductive dual backbone that consists of titanium nitride nanowires(TiN)coated on 3D carbon fiber(CF)could suppress the poor conductivity of moS_(2).Theo-retical calculations predict that both TiN and CF boost the electronic conductivity,while the moS_(2)will promote high ionic adsorption owing to the suitable adsorption *** as-prepared CF@TiN/moS_(2),with mass loading up to 12.5 mg cm^(−2),achieves a high areal capacity of up to 5.40 mah cm^(−2)under the current density of 0.6 ma cm^(−2)for sodium *** excellent performance of the hybrid can be attributed to buffer and conductivity enhancer features,allowing Na-ion to directly have contact with the CF@TiN/moS_(2)hybrid.A series of electrochemical analyses including cyclic voltammetry and symmetric cell analyses affirm the significant improvement in transport *** importantly,the CF@TiN/moS_(2)also achieves a high areal capacity of 3.29 mah cm^(−2)under the current density of 0.3 ma cm^(−2)as anode material for potassium ion batteries(PIBs),demonstrating that the scaffold-regulated strategy is a feasible strategy to enhance the kinetics of moS_(2)-based anodes for secondary-ion batteries and beyond.

关键词： moS_(2)nanosheets Flexible conductive TiN nanowires Kinetics High areal capacity Sodium-and potassium-ion batteries

Artemyrianosins A-J,cytotoxic germacrane-type sesquiterpene lactones from Artemisia myriantha

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Natural Products and Bioprospecting 2022年第1期12卷 199-210页

作者： Xin Zhang Yun-Bao ma Xiao-Feng He Tian-Ze Li Chang-An Geng Li-Hua Su Shuang Tang Zhen Gao Ji-Jun Chen State Key Laboratory of Phytochemistry and Plant Resources in West China Yunnan Key Laboratory of Natural Medicinal ChemistryKunming Institute of BotanyChinese Academy of Sciences132#Lanhei RoadKunming 650201YunnanPeople’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Ten new germacrane-type sesquiterpenoids,artemyrianosins A-J(1-10),were isolated from the aerial parts of Arte-misia *** structures were elucidated by spectral analyses including UV,IR,HRESImS,1D and 2D NmR,ECD and the absolute configurations of compounds 1 and 7-9 were characterized using X-ray *** isolates were tested their cytotoxicity against three human hepatoma cell lines(HepG2,Huh7,and SK-Hep-1),and com-pounds 1-3,7,and 10 showed cytotoxicity with IC50 values ranging from 43.7 to 89.3μ*** them,the most active compound 3 exhibited activity against three human hepatoma cell lines with IC50 values of 43.7μm(HepG2),47.9μm(Huh7),and 44.9μm(SK-Hep-1).

关键词： Artemisia myriantha Artemyrianosins A-J Germacrane-type sesquiterpenoids Cytotoxicity

Effects of multi-pass Friction Stir Processing on microstructures and mechanical Properties for 1060Al/Q235 Explosive Composite Plate

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Effects of Multi-pass Friction Stir Processing on Microstruc...

2019年焊接研究与技术开发新进展研讨会

作者： Jian Wang Yun Cheng Bo Li Cheng Chen Zongyi ma School of mechanical and Power Engineering Nanjing Tech University School of materials Science and Engineering Jiangsu University of Science and Technology Additive manufacturing and Intelligent Equipment Research Institute School of Mechanical and Power Engineering East China University of Science and Technology Shenyang National Laboratory for materials Science Institute of Metal Research Chinese Academy of Science

The aluminum/steel composite plate is often made by explosive welding owing to the high production efficiency. However, high production efficiencies often lead to steel cuttings, holes, cracks and other defects at the interface, therefore, multi-pass friction stir processing(m-FSP) for the repair of composite plate should be investigated. Results show that m-FSP has obvious repairing effects on the interface of aluminum/steel explosive composite plate. However, m-FSP can also form tunnel defects in the aluminum, especially when the passes are one and two. When the passes are three, m-FSP can eliminate the defects at the interface and reduce the tunnel defects through the plastic flow of aluminum. Since the shear strength of the composite plate after m-FSP has been improved, the above experimental ideas provide new ideas and methods for the repair of composite plates.

关键词： friction stir processing aluminum/steel explosive composite plate multi-pass bonding interface mechanical properties

Investigating the permeability of fractured rock masses and the origin of water in a mine tunnel in Shandong Province,China

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Investigating the permeability of fractured rock masses and ...

中国科学院地质与地球物理研究所2015年度（第15届）学术年会

作者： Jie Guo Haijun Zhao Fengshan ma Kepeng Li Chunhu Zhao Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of Sciences XI' an Research Institute of China Coal Technology & Engineering Group Corp.

The coastal Sanshandao mine is threatened by the overlying Quaternary water and *** an introduction to the geology and hydrogeological conditions in the mine area,a detailed hydrogeological survey and sampling were conducted and hydrochemical and stable isotopic(δ H andδO)tests on various waters were carried out to characterize the origin of water in the mine *** and statistical analysis indicated that the northwest-trending fractures with large dip angles and long trace lengths are well developed in the northeast compared with those in the southwest of the *** permeability coefficients of the rock masses are in the range 4.19×10-2.25×10m/s,indicating that the fractured rock masses have generally low *** seepage water had higher values of EC,total dissolved solids,and concentrations of most elements than the seawater and saline ***,the isotope composition of the waters indicated that the seepage water was more isotopically enriched than seawater but less than *** proportions of the three different sources were calculated based on hydrochemical and isotopic ***,the mine water was composed of 72%seawater,14.8%brine,and 13.2%atmospheric precipitation,***,some preventive measures are essential to avoid the probability of seawater inrush.

关键词： fractured rock mass isotope ratio permeability tensor Sanshandao mine water seepage

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铝合金表面微弧氧化涂层制备工艺设计

轻合金加工技术 2009年第12期37卷 45-48,57页

作者：全伟胡正前 Chernega.S.m. 马晋武汉理工大学机电学院湖北武汉430070 乌克兰国立技术大学工程物理系

用微弧氧化技术对铝合金表面进行强化处理,利用正交试验设计优化试验方案,按五因素(Na2SiO3浓度、KOH浓度、H3BO3浓度、H2O2浓度、微弧氧化电压)、四水平得到正交表,合理安排微弧氧化试验,达到优化微弧氧化工艺条件的目的;并用综合平衡... 详细信息

用微弧氧化技术对铝合金表面进行强化处理,利用正交试验设计优化试验方案,按五因素(Na2SiO3浓度、KOH浓度、H3BO3浓度、H2O2浓度、微弧氧化电压)、四水平得到正交表,合理安排微弧氧化试验,达到优化微弧氧化工艺条件的目的;并用综合平衡法评价各因素对陶瓷膜硬度和厚度影响的主次顺序和可能最优水平。结果表明,铝合金微弧氧化陶瓷膜的硬度和厚度受各因素水平的影响显著,其中Na2SiO3的浓度对陶瓷膜硬度和厚度两指标的影响最大;在最优工艺条件下(Na2SiO3浓度6 g/L、H3BO3浓度1.5 g/L、KOH浓度0.5 g/L、H2O2浓度X4、微弧氧化电压340V),陶瓷膜致密层硬度达到1 700 HV,膜层总厚度约200μm。

关键词：微弧氧化正交试验工艺设计陶瓷膜