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Crystal orientation and corrosion resistance of CuNi10Fe1Mn alloy billet under rotating electromagnetic field

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Rare Metals 2012年第6期31卷 552-555页

作者： fu yabo Cui Jing Li Tingju Taizhou Univ Sch Phys & Elect Engn Taizhou 318000 Peoples R China Civil Aviat Univ China Sch Airport Tianjin 300300 Peoples R China Dalian Univ Technol Sch Mat Sci & Engn Dalian 116024 Peoples R China

CuNi10Fe1Mn alloy billet under rotating electromagnetic field (REF) was characterized in this work. The change of the crystal orientation was first explored by X-ray diffraction (XRD) and scanning election microscope (SEM); the corrosion resistance was done by three electrodes system, and the natural sea water was used as corrosion medium. The results demonstrate that the strongest crystal orientation is transformed from crystal plane (200) to (111); moreover, the crystal plane (111) whose intensity is the strongest on the cross section and vertical section with REF causes the tubes be rolled easily, and the corrosion resistance of the billet is increasing with REF. As a result, properties of CuNi10Fe1Mn alloy tubes can be improved by REF.

关键词： rotating electromagnetic field (REF) crystal orientation corrosion resistance

Study of ultrahigh-purity copper billets refined by vacuum melting and directional solidification

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Rare Metals 2011年第3期30卷 304-309页

作者： fu yabo CHEN Jie LIU Ning LU Yiping LI Tingju YIN Guomao Key Laboratory of Materials Modification by Laser Ion and Electron Beams Ministry of Education Dalian University of Technology Dalian 116085 China School of Materials Science and Engineering Dalian University of Technology Dalian 116085 China

The purpose of this paper is to study large-sized copper billets refined with 5N ultrahigh purity after vacuum melting and directional solidifi-cation （VMDS）. The precise impurity analysis of copper billets was carried out with a glow discharge mass spectrometer （GDMS）. The re-sults demonstrate that the total concentration of twenty-two impurities is decreased by 63.1wt.%-66.5 wt.%. Ag, P, S, Na, Mg, Se, Zn, In and Bi are easy to be removed due to lgPimp - lgPCu 1.5, and they can be removed effectively under the vacuum condition of 1650-1700 K for 30 min. The electrical conductivity of 5N copper is higher than that of the raw material as the impurity concentrations decrease. The segrega-tion effect in directional solidification can be remarkable when the equilibrium distribution coefficient （k0） value is less than 0.65 due to the strong affinity of Cu for some metallic and non-metallic impurities.

关键词： copper refining vacuum melting directional solidification electrical conductivity

行星轧制条件下Cu-Cr-Zr合金棒坯的裂纹研究(英文)

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稀有金属材料与工程 2015年第3期44卷 567-570页

作者：付亚波崔静曹志强台州学院浙江台州318000 中国民航大学天津300300 大连理工大学辽宁大连116024

通过宏观和微观组织研究了棒坯边部、心部的晶粒尺寸及裂纹。利用横断面和纵断面的SEM微观组织分析了心部的裂纹形成机理。结果表明:边部的晶粒因为完成了动态再结晶,使晶粒比心部更加细化;心部约40μm的微裂纹是由于第二相粒子(体心立... 详细信息

通过宏观和微观组织研究了棒坯边部、心部的晶粒尺寸及裂纹。利用横断面和纵断面的SEM微观组织分析了心部的裂纹形成机理。结果表明:边部的晶粒因为完成了动态再结晶,使晶粒比心部更加细化;心部约40μm的微裂纹是由于第二相粒子(体心立方的沉淀相Cr及金属间化合物Cu51Zr14和Cu5Zr)作为微裂纹的形成源,因为晶粒粗大降低了其强度而诱发。因而细化晶粒能防止微裂纹的形成。裂纹形成机理适合微孔形核、长大和聚合的位错模型。

关键词：裂纹形成机理 Cu-Cr-Zr合金行星轧制位错模型

Enhancing weather predictions: Initial condition sensitivity and error dynamics in data assimilation

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Science China Earth Sciences 2025年第2期68卷 649-652页

作者： Weiwei fu Department of Atmospheric and Oceanic Sciences Fudan UniversityShanghai 200438China Key Laboratory of Polar Atmosphere-ocean-ice System for Weather and Climate Ministry of EducationFudan UniversityShanghai 200438China IRDR International Center of Excellence on Risk Interconnectivity and Governance on Weather Fudan UniversityShanghai 200438China

Data Assimilation(DA) plays a crucial role in modern numerical forecasting(Kalnay, 2002). It has been demonstrated that incorporating real-time observational data into forecast models significantly enhances the accuracy of both shortterm weather forecasts(Bauer et al., 2015;Bannister, 2017)and long-term climate predictions(Karspeck et al., 2013;Mochizuki et al., 2016).

关键词： weather assimilation forecasting

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Reducing the measurement errors in nonadiabatic holonomic quantum computers

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 60-66页

作者： Guo-fu Xu Department of Physics Shandong UniversityJinan 250100China

Nonadiabatic holonomic quantum computers serve as the physical platform for nonadiabatic holonomic quantum *** quantum computation has entered the noisy intermediate-scale era,building accurate intermediate-scale nonadiabatic holo-nomic quantum computers is clearly *** that measurements are the sole means of extracting information,they play an indispensable role in nonadiabatic holonomic quantum ***,developing methods to reduce measurement errors in nonadiabatic holonomic quantum computers is of great ***,while much attention has been given to the research on nonadiabatic holonomic gates,the research on reducing measurement errors in nonadiabatic holonomic quantum computers is severely *** this study,we propose a measurement error reduction method tailored for intermediate-scale nonadiabatic holonomic quantum *** reason we say this is because our method can not only reduce the measurement errors in the computer but also be useful in mitigating errors originating from nonadiabatic holonomic *** these features,our method significantly advances the construction of accurate intermediate-scale nonadiabatic holonomic quantum computers.

关键词： quantum holonomy quantum computation measurement errors

B4C-W2B5复合陶瓷的原位反应制备及其强韧化机理

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陶瓷学报 2019年第4期40卷 451-457页

作者：潘登李树丰张鑫潘渤付亚波西安理工大学材料学院陕西西安710048 西安热工研究院陕西西安710054 台州学院物理与电子工程学院浙江台州318000

碳化硼(B4C)陶瓷因致密化烧结温度高(>2200℃)和断裂韧性与硬度不匹配的关键问题而阻碍了其广泛应用。为了解决以上问题,本文提出采用粉末冶金法(P/M)通过石墨粉(Gr)与硼粉(B)之间的原位反应(in-situ)以降低其致密化烧结温度;同时通过... 详细信息

碳化硼(B4C)陶瓷因致密化烧结温度高(>2200℃)和断裂韧性与硬度不匹配的关键问题而阻碍了其广泛应用。为了解决以上问题,本文提出采用粉末冶金法(P/M)通过石墨粉(Gr)与硼粉(B)之间的原位反应(in-situ)以降低其致密化烧结温度;同时通过添加碳化鹄(WC)以生成板条状的五硼化二铸(W2B5)来提高其断裂韧性的研究思路,制备B4C-W2B5复合陶瓷。实验以硼(B)粉、石墨(Gr)粉以及碳化铸(WC)粉为原料,经过行星式高能球磨制备混合粉末,然后采用放电等离子烧结法(Spark plasma sintering,SPS)在烧结工艺为:压力30 MPa、烧结温度1100℃~1550℃~1700℃三步保温、烧结时间5 min^5 min^6 min的条件下对混合粉末进行固化烧结,分析了W2B5含量对复合陶瓷的微观结构和力学性能的影响,并对增韧机理进行了探讨。结果表明:当产物中B4C:W2B5=4:1(摩尔比),在1700℃下烧结,硬度和断裂韧性能够相平衡,致密度可达到100%,硬度为37.9 GPa,断裂韧性可达7.8 MPa·m^1/2.

关键词： B4C-W2B5 放电等离子烧结原位反应断裂韧性

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定向凝固结合电子束制备高纯铜的研究

真空科学与技术学报 2011年第4期31卷 495-499页

作者：陈洁付亚波刘宁卢一平李廷举大连理工大学材料科学与工程学院大连116024

对定向凝固结合电子束制备5N高纯铜进行了研究。首先采用真空感应熔炼4N(99.99%)阴极铜并进行定向凝固实验,然后利用电子束对定向凝固后的铸锭进行重熔精炼,利用辉光放电质谱仪进行成分分析。实验结果表明:真空熔炼可以有效去除铜中饱... 详细信息

对定向凝固结合电子束制备5N高纯铜进行了研究。首先采用真空感应熔炼4N(99.99%)阴极铜并进行定向凝固实验,然后利用电子束对定向凝固后的铸锭进行重熔精炼,利用辉光放电质谱仪进行成分分析。实验结果表明:真空熔炼可以有效去除铜中饱和蒸气压高的杂质;通过定向凝固,杂质元素含量沿铸锭轴向逐渐升高;经过组合工艺提纯后,总杂质含量由13.6×10-6降低至4.0×10-6,铜的纯度提高至99.9996%。

关键词：真空熔炼定向凝固电子束阴极铜

Energy injection, transport, and dissipation in Earth's magnetosphere

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Science China Earth Sciences 2025年第2期68卷 363-388页

作者： Huishan fu Jinbin CAO School of Space and Earth Sciences Beihang UniversityBeijing 100191China Key Laboratory of Space Environment Monitoring and Information Processing Ministry of Industry and Information TechnologyBeijing 100191China

The Earth's magnetosphere is a region occupied by many artificial satellites, and also is a region that spacecraft must cruise during the deep-space exploration. In this sense, the Earth's magnetosphere is closely related to human activity and is a candidate for us to expand our living space. Generally, the Earth's magnetosphere can preclude most energetic particles from the Sun and the interstellar space, effectively protecting human beings on the Earth from being attacked and thus making the Earth to be a habitable planet. However, in some conditions, the Earth's magnetosphere becomes dynamic and energetic, and consequently may damage the artificial satellites, threaten the astronauts' health, and disrupt the ground infrastructure, which leads to a decline in the national economy. Therefore, investigating how energy is injected into the magnetosphere, how it is transported in the magnetosphere, and how it is ultimately dissipated in the magnetosphere are the key issues in space physics. Targeting these key issues, in this paper, we review the recent progress on them. Particularly, we introduce the relevant scientific questions,models, methods, and spacecraft missions, for better building a physical link among the energy injection, transport, and dissipation in the magnetosphere, present an energy chain of the magnetosphere, reveal the relationship between such energy chain and the space weather events, and discuss the forecasting and warning methods for energetic-particle events in the magnetosphere. The magnetospheric energy chain discussed in this paper will help us reveal the mechanisms of space weather events, establish the models of space environment, and forecast the disastrous space weather events.

关键词： Earth's magnetosphere Energy injection Energy transport Energy dissipation

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Ideal balanced pairs in extriangulated categories

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Science China Mathematics 2025年第2期68卷 271-284页

作者： Rongrong Xu Xianhui fu School of Mathematics and Statistics Northeast Normal UniversityChangchun 130024China

Let C=(C,E,s)be an extriangulated *** this paper,we give the notion of ideal balanced pairs in C and some equivalent characterizations of ideal balanced *** show that there is a one-to-one correspondence between balanced pairs and ideal balanced pairs satisfying certain conditions when C is of a negative first *** also prove that there is a bijective correspondence between ideal balanced pairs(I,J)and additive subfunctors F■E with enough projective morphisms and enough injective morphisms in C.

关键词： extriangulated category ideal balanced pair strong-precovering ideal ideal cotorsion pair