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钕在镁合金熔炼过程中行为的热力学分析

中国稀土学报 2020年第5期38卷 661-666,I0003页

作者：栗聖凯邹胜伟李明照山西工程职业学院冶金与环境工程系山西太原030009 太原理工大学材料科学与工程学院山西太原030024

通过理论计算方法对Nd在镁合金熔炼过程中的行为进行了热力学分析,结果表明:Nd和O的结合力大于Mg和O的结合力,镁合金熔体中如果存在MgO, Nd将夺取其中的氧,从而减少MgO对镁合金的不利影响;Nd与MgCl2容易进行反应,Nd的加入可以减少镁合... 详细信息

通过理论计算方法对Nd在镁合金熔炼过程中的行为进行了热力学分析,结果表明:Nd和O的结合力大于Mg和O的结合力,镁合金熔体中如果存在MgO, Nd将夺取其中的氧,从而减少MgO对镁合金的不利影响;Nd与MgCl2容易进行反应,Nd的加入可以减少镁合金中的Cl-,进而提高镁合金的耐蚀性能;Nd在镁合金中和MgO, MgCl2反应时会造成Nd的损耗,要考虑其损耗才能准确控制合金成分;Nd与镁合金的主成分Mg, Al形成化合物。

关键词：镁合金熔炼 Nd 热力学耐蚀性能

Nd Isotopic aNd Model Age Study of the ShaNdong Province, North China Craton: Implications for Correlation with South Korea

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Journal of Earth Science 2019年第5期30卷 938-951页

作者： Feifei Liu Yaoqi Zhou School of Geosciences China University of Petroleum Qingdao 266580 China Function Laboratory for Marine Mineral Resource Geology aNd Exploration National Laboratory for Marine Science and Technology Qingdao 266071 China

The geological units in ShaNdong Province, North China are important parts of the North China Craton aNd offer important insights into their crustal evolutionary history. This paper presents 611 sets of Nd isotopic data of Archean–Mesozoic rocks from ShaNdong including the Luxi, Jiaobei, aNd Sulu terranes, which provides important constraints for crustal growth aNd reactivation. Nd-depleted mantle model ages(TDM) of Archean rocks with positive εNd(t) values showed that ca. 2.9 aNd 2.8–2.7 Ga were the most important periods of crustal growth in the Jiaobei aNd Luxi terranes, respectively, while the period of ca. 2.6–2.5 Ga in the Jiaobei terrane likely iNdicates a coherent event of crustal growth aNd reworking. During the Proterozoic, multi-stage rifting aNd collisional orogenic events possibly led to the reworking of Archean crust in the source region. The Nd isotopic data of the Paleoproterozoic aNd Neoproterozoic rocks from Sulu iNdicated significant reworking of older crust with juvenile magmatic input. Crustal reactivation occurred during the Mesozoic. The younger TDM ages of the Mesozoic rocks with low negative εNd(t) values iNdicate that a juvenile crustal/mantle component was added to the ancient basement. The reactivation reflectes significant crust-mantle interaction via the mechanism of crustal subduction aNd mantle-derived magma uNderplating, or possibly asthenospheric upwelling. In addition, the crustal correlation between ShaNdong aNd Korea(including the Gyeonggi massif, Ogcheon belt, aNd Yeongnam massif) is established in this study. The TDM age distribution provides evidence favoring the affinity relationship between the Gyeonggi massif aNd Ogcheon belt of South Korea aNd the Jiaobei aNd Sulu terranes of ShaNdong, while the Yeongnam massif is more correlated with the South China Block.

关键词： Nd model age crustal growth crust reactivation ShaNdong geochemistry Korea

Generation of high-contrast, joule-level pulses based on Nd:glass chirped pulse amplification laser

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High Power Laser Science aNd Engineering 2016年第4期4卷 1-6页

作者： Xiaoming Lu Yujie Peng Yanyan Li Xinliang Wang Xiaoyang Guo Yi Xu Yuxin Leng State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences School of Physics Science aNd Engineering Tongji University

We demonstrate a high-contrast, joule-level Nd:glass laser system operating at 0.5 Hz repetition rate based on a double chirped pulse amplification(CPA) scheme. By injecting high-contrast, high-energy seed pulses into the Nd:glass CPA stage, the pulse energy is amplified to 1.9 J through two optical parametric CPA stages aNd two Nd:glass amplifiers. The temporal contrast of compressed pulse is measured down to the level of 10^(-8)at tens of ps, aNd 10^(-10) near 200 ps before the main pulse, respectively.

关键词： chirped pulse amplification Nd glass temporal contrast

Silver nanorods absorber for passively Q-switched Nd,Gd:CaF_2 laser

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Chinese Optics Letters 2018年第2期16卷 98-102页

作者：吴永静逄思远祖玉倩彭倩倩杨济民刘杰苏良碧 ShaNdong Provincial Key Laboratory of Optics aNd Photonic Device School of Physics and ElectronicsShandong Normal University Synthetic Single Crystal Research Center Shanghai Institute of Ceramics Chinese Academy of Sciences Key Laboratory of Transparent aNd Opto-functional Inorganic Materials Shanghai Institute of CeramicsChinese Academy of Sciences Institute of Data Science aNd Technology Shandong Normal University

Using a novel silver nanorods absorber with a localized surface plasmon resonance absorption peak at 1.06 μm,we obtain a diode-pumped passively Q-switched（PQS） Nd,Gd：CaF2 disordered crystal laser output. Its PQS pulse laser performances are studied comprehensively aNd systematically in this Letter. The single pulse energy aNd peak power can be attained to 2.15 μJ aNd 2.06 W, respectively.

关键词： Gd Ca Nd Silver nanorods absorber for passively Q-switched Nd,Gd:CaF2 laser

Micromagnetic simulation on magnetic properties of Nd2Fe14B/α-Fe nanocomposites with Fe nanowires as the soft phase

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Frontiers of Materials Science 2018年第4期12卷 348-353页

作者： Wei LI Lizhong ZHAO Zhongwu LIU School of Materials Science aNd Engineering South China University of TechnologyGuangzhou 510640China

Fe nanowire array with strong shape anisotropy was employed as the soft phase in Nd-Fe-B based nanocomposites. The effects of the Fe nanowire distribution on magnetic properties of the nanocomposites were investigated by micromagnetic simulation. The results iNdicate that the shape anisotropy of Fe wires added in the same direction as the uniaxial magnetocrystalline anisotropy of the hard phase cannot increase the coercivity of the nanocomposite. When the nanowires are distributed perpeNdicular to the easy axis of the hard phase, the shape anisotropy of soft phase can retard the moments from rotating to the full reversed direction, leading to enhanced coercivity. In addition, with increasing the nanowire diameter, the coercivity of the nanocomposite decreases, but the dipolar interaction shows different roles in magnetic reversal of nanocomposite for different distributions of nanowires. The current results suggest that the coercivity of the Nd2Fe14B/α-Fe nanocomposite can be enhanced by introducing the soft magnetic nanowire array with the diameter less than the exchange length aNd with the long axis along the direction other than the easy axis of hard phase.

关键词： Nd 2 Fe 14 B/α-Fe nanocomposite micromagnetic simulation Fe nanowires shape anisotropy exchange coupling

Passively Q-Switched Nd:YVO_4 Laser Using a Gold Nanotriangle Saturable Absorber

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Chinese Physics Letters 2018年第6期35卷 33-36页

作者：秦琦李平白金玺王丽丽刘丙海陈晓寒 School of Information Science aNd Engineering and Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong University

A passively Q-switched Nd：YVO4 laser at 1064 nm is demonstrated based on a gold nanotriangle saturable absorber（GNT SA）.UNder a pump power of 3.82 W,the maximum average output power of 218mW is achieved,correspoNding to a slope efficiency of 12.9%.The minimum pulse width is 165ns aNd the maximum pulse repetition rate is 300kHz at the pump power of 3.48 W.Our results prove that the GNT SA is a promising saturable absorber for near-infrared lasers.

关键词： GNT Nd Passively Q-Switched Nd:YVO4 Laser Using a Gold Nanotriangle Saturable Absorber SA

High-beam-quality, 5.4 J, 5 Hz diode-pumped Nd:YAG active mirror laser amplifier

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Chinese Optics Letters 2018年第12期16卷 42-44页

作者：刘晶李磊施翔春陈汝风王建磊陈卫标 Shanghai Key Laboratory of All Solid-State Laser aNd Applied Techniques Shanghai Institute of Optics and Fine MechanicsChinese Academy of Sciences

A high-beam-quality diode-pumped neodymium-doped yttrium aluminum garnet(Nd:YAG) active mirror laser amplifier was demonstrated. The size of the Nd:YAG crystal was 48 mm × 42 mm × 11 mm with 0.6 at.% Nd doped. When the pump energy was 26.8 J aNd the input energy was 0.3 J, the output pulse energy reached 5.4 J, aNd the pulse width of 11.3 ns at a 5 Hz repetition rate was obtained for the two gain modules in three-pass amplification, with correspoNding optical-to-optical efficiency of 21.2%. The beam quality was measured as M_x^2=2.48 aNd M_y^2=2.43 in horizontal aNd vertical directions, respectively.

关键词： YAG Hz diode-pumped Nd:YAG active mirror laser amplifier High-beam-quality Nd

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拉萨地体东南部整体地壳成分及其成因分析

地球科学 2019年第6期44卷 1809-1821页

作者：郭京梁张宏飞徐旺春郭亮吴耀崔丹丹中国地质大学地球科学学院湖北武汉430074 中国地质大学地质过程与矿产资源国家实验室湖北武汉430074

造山带地壳结构和成分的基本特征对于认识大陆地壳成分演化和区域成矿背景具有重要意义.综合青藏高原拉萨地体东南部地球物理、高温高压岩石物性和岩浆岩地球化学资料,分析该地区地壳整体成分特征,并探讨其可能成因.该地区平均地壳波速... 详细信息

造山带地壳结构和成分的基本特征对于认识大陆地壳成分演化和区域成矿背景具有重要意义.综合青藏高原拉萨地体东南部地球物理、高温高压岩石物性和岩浆岩地球化学资料,分析该地区地壳整体成分特征,并探讨其可能成因.该地区平均地壳波速显著低于全球大陆和造山带地壳的平均值,表明地壳整体具有中酸性成分,下地壳特征也可由中性岩石(残余体性质的中性含石榴石麻粒岩)解释.拉萨地体东南部整体地壳成分特征应与多阶段长英质化有关,包括碰撞前大陆弧演化阶段(以堆晶或残余体下地壳拆沉为主)和碰撞后高原垮塌阶段(以加厚下地壳拆沉为主,伴随印度古老长英质陆壳物质的俯冲回返/构造底侵).拉萨地体是研究大陆地壳成分演化的绝佳区域,亟待进一步开展多学科综合研究.

关键词：大陆地壳成分演化拆沉 Nd 同位素冈底斯青藏高原岩石学

Nd对铸态Mg-10Gd-0.7Al合金组织和力学性能的影响

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材料热处理学报 2021年第9期42卷 58-67页

作者：王凌浩单陇红黎志勇广东理工学院工业自动化系广东肇庆526100

采用熔炼铸造法制备了Mg-10Gd-xNd-0.7Al(x=0,1,1.5,2 mass%)合金,通过光学显微镜、X射线衍射仪、扫描电镜、能谱仪和电子拉伸试验机等设备研究了Nd对铸态Mg-10Gd-0.7Al合金组织和力学性能的影响,结合边-边匹配理论讨论了Nd对合金晶粒... 详细信息

采用熔炼铸造法制备了Mg-10Gd-xNd-0.7Al(x=0,1,1.5,2 mass%)合金,通过光学显微镜、X射线衍射仪、扫描电镜、能谱仪和电子拉伸试验机等设备研究了Nd对铸态Mg-10Gd-0.7Al合金组织和力学性能的影响,结合边-边匹配理论讨论了Nd对合金晶粒的细化机理。结果表明:铸态Mg-10Gd-0.7Al合金的组织由粗大的α-Mg基体、Mg_(5) Gd相和Al_(2) Gd相组成,添加Nd元素后,合金产生了新相Al_(2) Nd和Mg_(41) Nd_(5),且细化了晶粒;随着Nd添加量的增加,铸态Mg-10Gd-xNd-0.7Al合金的室温拉伸力学性能先升高后降低,当Nd的添加量为1.5 mass%时,合金综合力学性能最好,其抗拉强度为200.32 MPa,屈服强度为175.47 MPa,伸长率为4.43%;加入Nd后,合金的断裂方式由脆性断裂逐渐转变为韧性断裂。

关键词： Mg-10Gd-0.7Al合金 Nd 细化机理力学性能