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澳大利亚科学家利用镱元素研制高精确度原子钟

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稀土 2014年第2期35卷 87-87页

西澳大利亚大学副教授约翰-迈克菲伦领导的研究小组研制出精确度达到世界领先水平的原子钟。他们的原子钟将用于一项实验,测量宇宙的一个基本常数。迈克菲伦等人研制的原子钟采用稀土元素镱的原子制造。与采用微波的标准原子钟不同,镱... 详细信息

西澳大利亚大学副教授约翰-迈克菲伦领导的研究小组研制出精确度达到世界领先水平的原子钟。他们的原子钟将用于一项实验,测量宇宙的一个基本常数。迈克菲伦等人研制的原子钟采用稀土元素镱的原子制造。与采用微波的标准原子钟不同,镱原子钟将在更高的光频段下运转,将时间分割成大约10万份,用以获得更高的精确度。为了制造这种原子钟,他们需要使用激光器、光学装置、电子装置、不锈钢和超高真空系统,

关键词：西澳大利亚高精确度原子钟镱元素科学家利用超高真空系统稀土元素

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稀土元素对钛合金的作用机制研究现状及展望

热加工工艺 2019年第9期48卷 1-4页

作者：贾宝华刘翔顾永强李革内蒙古科技大学土木工程学院内蒙古包头014010

在钛合金中添加稀土元素可以改变合金的微观结构而大大改善合金的力学性能。本文在分析稀土合金的制备和稀土元素对合金的作用机制研究基础上,指出可将稀土镱元素对钛合金的作用机制作为未来的研究方向。

关键词：稀土钛合金作用机制镱元素

Effect of Yb additions on microstructures and properties of 7A60 aluminum alloy

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中国有色金属学会会刊：英文版 2008年第1期18卷 28-32页

作者：方华婵陈康华张茁祝昌军 State Key Laboratory of Powder Metallurgy Central South University

Al-Zn-Mg-Cu-Zr alloys containing Yb were prepared by cast *** of 0.30% Yb additions on the microstructure and properties of 7A60 aluminum alloys with T6 and T77 aging treatments was investigated by TEM,optical microscopy,hardness and electric conductivity measurement,tensile test and stress corrosion cracking *** results show that the Yb additions to high strength Al-Zn-Mg-Cu-Zr aluminum alloys can produce fine coherent *** dispersoids can strongly pin dislocation and subgrain boundaries,which can significantly retard the recrystallization by inhibiting the nucleation of recrystallization and the growth of subgrains and keeping low-angle subgrain *** additions can obviously enhance the resistance to stress corrosion cracking and the fracture toughness property,and mildly increase the strength and ductility with T6 and T77 treatments.

关键词： Al-Zn-Mg-Cu合金机械力学腐蚀性能镱元素

High-strength wrought magnesium alloy with dense nano-scale spherical precipitate

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Chinese Science Bulletin 2007年第13期52卷 1867-1871页

作者： YU WenBin CHEN ZhiQian CHENG NanPu GAN BingTai HE Hong LI XueLian HU JinZhu School of Materials Science and Engineering Southwest University Chongqing 400715 China

This paper reported the influences of Yb addition on the precipitate and mechanical properties of wrought magnesium alloy ZK60. The ingots of ZK60-1.78Yb (wt%, 0.26 at%) alloys were cast using permanent mould and extruded at 370℃ . By means of TEM and HRTEM, it was observed that Yb affected the precipitate and precipitation of ZK60-1.78Yb alloys significantly. Dynamic precipitation occurred in the as-extruded alloy and spherical nano-scale precipitate with high density and homoge-neity exhibited in the aged alloys. The precipitate particles were about 5-20 nm in diameter, 10-30 nm in average space length. The tensile test results showed that the ZK60-1.78Yb alloy had excellent pre-cipitation strengthening response with the maximum tensile strength 417.5 MPa at ambient tempera-ture.

关键词：镁合金镱元素动力学沉淀物张力强度

[Na(THF)_（2）(μ_（2）-η^(5)-Cp)(η^(5),η^(5),η^(1)- Cp_(3)Yb)(THF)]_(n):The synthesis and X-ray structure of an anionic organolanthanide polymer formed via self-assembly

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Chinese Science Bulletin 2005年第17期50卷 1843-1845页

作者： HUANG Dan SUN Hongmei LIU Taiqi XU Fan SHEN Qi The Key Laboratory of Organic Synthesis of Jiangsu Province Department of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 China

Cp2Yb·2THF reacts with CpNa in 1:1 molar ratio in THF at 40℃ for 2 h, and the in situ generated ani-onic divalent complex NaYbCp3(THF)n reacts further with an excess of CpH at 40℃ for 48 h, after work-up, affording the trivalent anionic ytterbium complex [Na(THF)2(μ2-η5-Cp) (η5,η5,η1-Cp3Yb)(THF)]n (1) by oxidation reaction of Cp2Yb with CpH. Crystal structure determination reveals that com-plex 1 has one-dimension polymeric chains of distinct Na(THF)2(μ2-η5-Cp)(η5,η5,η1-Cp3Yb)(THF) units, which were formed by the coordination of the bridging Cp ligand with Cp3Yb·THF and Na(THF)2 in η5,η5 mode via self-assembly.

关键词： X-射线有机原子序数阴极自集合系统镱元素复合晶体结构

Ytterbium-doped fiber ring laser in multi-pulse operation

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Optoelectronics Letters 2007年第6期3卷 401-403页

作者： YANG Ling-zhen WANG Yun-cai CHEN Guo-fu WANG Yi-shan ZHAO Wei Physics Department Taiyuan University of Technology Taiyuan 030024 China State Key Laboratory of Transient Optics Technology Xi＇an Institute of Optics and Precision Mechanics ChineseAcademy of Sciences Xi＇an 710068 China

An Ytterbium-doped mode-locked fiber laser using the polarization sensitive isolator and polarization controllers (PC) is reported. In the normal dispersion, the fiber laser can oscillate at the multi-pulse states by adjusting the position of the PC. On the condition that the polarization state isn’t changed, the outputs of Ytterbium-doped mode-locked fiber laser change from single pulse to multi-pulse by increasing the pump power. The fiber laser can achieve different multi-pulse output by adjusting the PC1 and PC2 carefully.

关键词：镱元素纤维环激光多脉冲操作光纤元件

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冶金

中国中小企业 2004年第5期 77-77页