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Journal of Magnesium and Alloys 2023年第8期11卷 2891-2900页

作者： Yiping WU Yuzhen JIA Sha Zhang Yu Liu hanqing xiong Gang Chen Department of Mechanical and Electrical Engineering Changsha UniversityChangsha 410003China Bichamp Cutting Technology(Hunan)Co. LtdChangsha 410200China College of Material Science and Engineering Hunan UniversityChangsha Hunan 410082China

Flow softening behavior of a homogenized Mg-7Gd-4Y-1Nd-0.5Zr alloy under compression to a final strain of∼1.8 at elevated temperatures of 450∼550℃ and a constant strain rate of 2s^(−1) has been investigated by optical microscopy,scanning electron microscopy,electron back-scattered diffraction and transmission electron *** results show that true stress first rises to the peak point and then drops to the bottom value and increases again with further increasing strain at each *** dynamic recrystallization(DRX)and continuous DRX contribute to the formation of new fine grains at temperatures 450∼475℃ when the restoration is caused by both DRX and texture change due to extension twinning,resulting in the larger softening degrees compared with the softening effects owing to continuous DRX and discontinuous DRX at 500∼550℃ when twinning activation is suppressed.500℃ is the transition temperature denoting a significant decline in the contribution of twinning and TDRX to the strain with increasing *** cuboid-shape phase exists in both homogenized and compressed samples,while the compositions are varied.

关键词： Mg-Gd-Y alloy Elevated temperature compression Flow softening Dynamic recrystallization

Super-resolution vibrational microscopy by stimulated Raman excited fluorescence

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Light(Science & Applications) 2021年第5期10卷 906-915页

作者： hanqing xiong Naixin Qian Yupeng Miao Zhilun Zhao Chen Chen&Wei Min Department of Chemistry Columbia UniversityNew YorkNY10027USA

Inspired by the revolutionary impact of super-resolution fluorescence microscopy,super-resolution Raman imaging has been long pursued because of its much higher chemical specificity than the fluorescence ***,vibrational contrasts are intrinsically less sensitive compared with fluorescence,resulting in only mild resolution enhancement beyond the diffraction limit even with strong laser excitation *** such,it is still a great challenge to achieve biocompatible super-resolution vibrational imaging in the optical *** 2019 Stimulated Raman Excited Fluorescence(SREF)was discovered as an ultrasensitive vibrational spectroscopy that combines the high chemical specificity of Raman scattering and the superb sensitivity of fluorescence *** we developed a novel super-resolution vibrational imaging method by harnessing SREF as the contrast *** first identified the undesired role of anti-Stokes fluorescence background in preventing direct adoption of super-resolution fluorescence *** then devised a frequency-modulation(FM)strategy to remove the broadband backgrounds and achieved high-contrast SREF *** by newly synthesized SREF dyes,we realized multicolor FM-SREF imaging with nanometer spectral ***,by integrating stimulated emission depletion(STED)with background-free FM-SREF,we accomplished high-contrast super-resolution vibrational imaging with STED-FM-SREF whose spatial resolution is only determined by the signal-to-noise *** our proof-of-principle demonstration,more than two times of resolution improvement is achieved in biological systems with moderate laser excitation power,which shall be further refined with optimized instrumentation and imaging *** its super resolution,high sensitivity,vibrational contrast,and mild laser excitation power,STED-FM-SREF microscopy is envisioned to aid a wide variety of applications.

关键词： field. vibrational resolution

Transient stimulated Raman scattering spectroscopy and imaging

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Light(Science & Applications) 2024年第4期13卷 654-663页

作者： Qiaozhi Yu Zhengjian Yao Jiaqi Zhou Wenhao Yu Chenjie Zhuang Yafeng Qi hanqing xiong National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing 100871China Biomedical Engineering Department College of Future TechnologyPeking UniversityBeijing 100871China

Stimulated Raman scattering(SRS)has been developed as an essential quantitative contrast for chemical imaging in recent ***,while spectral lines near the natural linewidth limit can be routinely achieved by state-of-the-art spontaneous Raman microscopes,spectral broadening is inevitable for current mainstream SRS imaging *** is because those SRS signals are all measured in the frequency *** is a compromise between sensitivity and spectral resolution:as the nonlinear process benefits from pulsed excitations,the fundamental time-energy uncertainty limits the spectral ***,the spectral range and acquisition speed are mutually *** we report transient stimulated Raman scattering(T-SRS),an alternative time-domain strategy that bypasses all these fundamental conjugations.T-SRS is achieved by quantum coherence manipulation:we encode the vibrational oscillations in the stimulated Raman loss(SRL)signal by femtosecond pulse-pair sequence excited vibrational wave packet *** Raman spectrum was then achieved by Fourier transform of the time-domain SRL *** all Raman modes are impulsively and simultaneously excited,T-SRS features the natural-linewidth-limit spectral line shapes,laser-bandwidth-determined spectral range,and improved ***~150-fs laser pulses,we boost the sensitivity of typical Raman modes to the sub-mM *** all-plane-mirror high-speed time-delay scanning,we further demonstrated hyperspectral SRS imaging of live-cell metabolism and high-density multiplexed imaging with the natural-linewidth-limit spectral resolution.T-SRS shall find valuable applications for advanced Raman imaging.

关键词： scattering excited mutually

Enhanced Mechanical Properties of AA5083 Matrix Composite via Introducing Al_(0.5)CoCrFeNi Particles and Cryorolling

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Acta Metallurgica Sinica(English Letters) 2022年第6期35卷 879-889页

作者： Hao Gu Zhide Li Kaiguang Luo Laxman Bhatta hanqing xiong Yun Zhang Charlie Kong Hailiang Yu State Key Laboratory of High Performance Complex Manufacturing Central South UniversityChangsha 410083China College of Mechanical and Electrical Engineering Central South UniversityChangsha 410083China Mark Wainwright Analytical Center University of New South WalesSydneyNSW 2052Australia Light Alloys Research Institute Central South UniversityChangsha 410083China

High-entropy alloy particles(HEAPs)can markedly enhance the mechanical properties of metal matrix composites(MMCs).In this study,AA5083/Al_(0.5) CoCrFeNi HEAPs MMCs with diff erent HEAPs contents(0,1,and 3 wt%)were prepared via a stir-casting,and then these MMCs sheets were hot rolled(573 K)and cryorolled(77 K),*** mechanical properties of the MMCs sheets were measured by tensile testing and microhardness ***,their microstructures were analyzed by scanning electron microscopy and transmission electron *** revealed that the ultimate tensile strength(UTS)of the as-cast AA5083/Al_(0.5) CoC rF eN i HEAPs MMCs were improved from 203 to 257 MPa by adding 3 wt%*** the mechanical properties of the MMCs sheets were improved after *** cryorolling with 50%rolling reduction ratio,the MMCs with 1 wt%HEAPs had an UTS of 382 MPa,which was 1.9 times that of the MMCs before ***,the strengthening mechanisms of HEAPs and cryorolling on the AA5083/HEAPs MMCs were discussed.

关键词： Metal matrix composite Cryorolling Mechanical properties High-entropy alloy particle

Corrosion behavior of Mg-Zn-Ca amorphous alloys with Nd addition in simulated body fluids

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China Foundry 2014年第6期11卷 503-509页

作者： Qin Chunling Xiao Tongna Li Yongyan Wang Zhifeng Liu Li xiong hanqing Zhao Weimin School of Materials Science and Engineering Hebei University of Technology School of Materials Science and Engineering Central South University

The effects of Nd addition on corrosion behavior of Mg66Zn30Ca4 amorphous alloys in simulated body fluids （SBF） were studied in this paper. Electrochemical properties of the samples before and after corrosion were determined. Surface morphologies of samples after immersion in SBF at 37 ℃ for different times were observed under scanning electron microscope （SEM）. Results show that the corrosion resistance of Mg-based alloys in SBF is improved with the addition of Nd element. The electrochemical properties indicate that microalloying Nd element to the alloys leads to an ennoblement in the open circuit potentials of the alloys and a decrease in the anodic current density in SBF, especially for the Mgee66-xZn30Ca4Ndx alloys with Nd content of 1.0at.%-1.5at.%. It was observed that the surface morphologies of the alloys immersed in SBF change with the Nd addition. A flake- like structure parallel to the alloy substrate formed on the surface of 1.0at.% Nd-containing alloy immersed in SBF for 7 days improves the corrosion resistance of the amorphous alloys by blocking the corrosion liquid from attacking the alloys.

关键词： Mg alloy amorphous alloy corrosion behavior SBF electrochemical measurements

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时域相干拉曼散射技术浅析(特邀)

激光与光电子学进展 2024年第6期61卷 135-144页

作者：余乔智祁亚峰熊汗青北京大学未来技术学院国家生物医学成像科学中心北京100871

相干拉曼散射(CRS)技术作为一种重要的无标记化学成像技术,通过相干激发分子协同振动对拉曼散射信号进行增益,显著地提高了成像速度,广泛应用于材料学、生物化学、肿瘤诊断、药代动力学等领域。超快脉冲激光器的出现实现了亚皮秒持续时... 详细信息

相干拉曼散射(CRS)技术作为一种重要的无标记化学成像技术,通过相干激发分子协同振动对拉曼散射信号进行增益,显著地提高了成像速度,广泛应用于材料学、生物化学、肿瘤诊断、药代动力学等领域。超快脉冲激光器的出现实现了亚皮秒持续时间的脉冲输出,使得通过脉冲激发实现大量振动模式的同步相干激发成为新的CRS实现途径。从相干拉曼散射基本原理出发,介绍时域相干拉曼散射的主要实现途径,着重讨论时域受激拉曼散射(SRS)和时域相干反斯托克斯拉曼散射(CARS)的最新进展与应用。

关键词：拉曼光谱技术相干拉曼散射受激拉曼散射相干反斯托克斯拉曼散射时域频域

Resonance-assisted light–control–light characteristics of SnS_2 on a microfiber knot resonator with fast response

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Photonics Research 2018年第12期6卷 1137-1143页

作者： HUIHUI LU ZHONGMIN WANG ZHIJIN HUANG JUN TAO hanqing xiong WENTAO QIU HEYUAN GUAN HUAZHUO DONG JIANGLI DONG WENGUO ZHU JIANHUI YU YONGCHUN ZHONG YUNHAN LUO JUN ZHANG ZHE CHEN Guangdong Provincial Key Laboratory of Optical Fiber Sensing and Communications Department of Optoelectronic EngineeringJinan University Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Education Institutes Jinan University

An all-optical light–control–light functionality with the structure of a microfiber knot resonator (MKR) coated with tin disulfide (SnS_2) nanosheets is experimentally demonstrated. The evanescent light in the MKR [with a resonance Q of ～59,000 and an extinction ratio (ER) of ～26 dB] is exploited to enhance light–matter interaction by coating a two-dimensional material SnS_2 nanosheet onto it. Thanks to the enhanced light–matter interaction and the strong absorption property of SnS_2, the transmitted optical power can be tuned quasi-linearly with an external violet pump light power, where a transmitted optical power variation rate ΔT with respect to the violet light power of ～0.22 dB∕mW is obtained. In addition, the MKR structure possessing multiple resonances enables a direct experimental demonstration of the relationship between resonance properties (such as Q and ER), and the obtained ΔT variation rate with respect to the violet light power. It verifies experimentally that a higher resonance Q and a larger ER can lead to a higher ΔT variation rate. In terms of the operating speed, this device runs as fast as ～3.2 ms. This kind of all-optical light–control–light functional structure may find applications in future all-optical circuitry, handheld fiber sensors, etc.

关键词： response fast experimental optical multiple pump can tin

强基面织构AZ31合金压缩过程中的孪晶对行为

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稀有金属材料与工程 2020年第2期49卷 429-434页

作者：熊汉青吴懿萍贾寓真谢邵辉李国锋长沙学院湖南长沙410003 湖南泰嘉新材料科技股份有限公司湖南长沙410200

挤压态AZ31合金在室温下沿挤压方向进行压缩变形,合金中产生大量的拉伸孪晶。综合分析了孪晶对的斯密特因子(SF)和应变兼容因子(m_f),其中孪晶对包括相连的孪晶对和非相连的孪晶对。结果表明:相连的孪晶对优先在取向差约为25°的相邻晶... 详细信息

挤压态AZ31合金在室温下沿挤压方向进行压缩变形,合金中产生大量的拉伸孪晶。综合分析了孪晶对的斯密特因子(SF)和应变兼容因子(m_f),其中孪晶对包括相连的孪晶对和非相连的孪晶对。结果表明:相连的孪晶对优先在取向差约为25°的相邻晶粒的晶界上形核。大约88%的相连孪晶对具有很高的斯密特因子,大约76%的相连孪晶对具有很高的应变兼容因子。低斯密特因子的孪晶对的发生能够通过高应变兼容因子进行解释。大约23%的非相连孪晶对的应变兼容因子接近于0。

关键词： AZ31合金孪晶斯密特因子应变兼容因子

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钳工实训中训练项目的开发实践

科技创新导报 2022年第2期19卷 176-178页

作者：熊翰卿张家界航空工业职业技术学院湖南张家界427000

机电专业钳工实训在高职教育当中是一门具有较强基础性的金工实训学科,且其在实训过程中也具有较大强度,其中,场地环境较差、传统实训方式单调、教学内容不具新意等问题导致学生学习兴趣较低。基于此,本文将主要针对如在高职钳工实训课... 详细信息

机电专业钳工实训在高职教育当中是一门具有较强基础性的金工实训学科,且其在实训过程中也具有较大强度,其中,场地环境较差、传统实训方式单调、教学内容不具新意等问题导致学生学习兴趣较低。基于此,本文将主要针对如在高职钳工实训课程当中的训练项目加以有效开发与实践展开相关探讨分析,强调实践教学策略会导致学生缺乏基本原理的认知能力,过多地偏向实操教学方法会导致学生缺乏对原理的认知、对实际操作缺乏深入的掌握。

关键词：高职钳工实训项目训练研究

锂离子电池封装用Al-Ni层状材料的复合过程及应用特性研究（英文）

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稀有金属材料与工程 2016年第5期45卷 1100-1105页

作者：余琨熊汉青戴翌龙滕飞范素峰乔雪岩文利中南大学湖南长沙410083 烟台南山学院山东烟台265713

采用冷轧复合工艺制备了用于锂离子电池封装用的层状Al-Ni双金属复合带材。针对轧制复合工艺和热处理退火工艺对Al-Ni双金属复合带材界面化合物种类、结构及其应用特性进行了研究。结果表明：合适的轧制变形量是实现Al层和Ni层复合的关... 详细信息

采用冷轧复合工艺制备了用于锂离子电池封装用的层状Al-Ni双金属复合带材。针对轧制复合工艺和热处理退火工艺对Al-Ni双金属复合带材界面化合物种类、结构及其应用特性进行了研究。结果表明：合适的轧制变形量是实现Al层和Ni层复合的关键因素,在本实验中复合轧制的变形量应控制在50%-60%之间。在后续退火工艺中,Al层和Ni层界面上首先形成的是Al3Ni相,该相有利于Al层和Ni层实现牢固的冶金结合。随着退火时间的延长,随后会形成较脆性的Al3Ni2相,该相以层状形式存在两层金属中间,容易造成Al层和Ni层金属的剥离,因此通过退火工艺控制界面化合物形成的类型和结构十分重要。实验发现,在698-748 K温度范围内退火1 h的轧制复合Al-Ni双金属复合带材,具有好的抗折弯效果、稳定的焊接性能和合适的电阻值,可以作为锂电池封装材料来进行使用。

关键词： Al-Ni层状复合材料轧制复合界面