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Correlation between boson peak and thermal expansion manifested by physical aging and high pressure

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 72-77页

作者： Rongjie Xue Linzhi Zhao Yunqi Cai Jiaojiao Yi Jinguang Cheng Ping Wen Weihua Wang Mingxiang Pan haiyang bai Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Materials Engineering Jiangsu University of TechnologyChangzhou 213001China College of Materials Science and Opto-Electronic Technology University of Chinese Academy of SciencesBeijing 100049China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

We investigate the effects of high pressure and physical aging on the boson peak and thermal expansion of a typical metallic glass. Specifically, the thermal expansion coefficient and boson peak intensity monotonically decrease during physical *** the increase of high pressure, the boson peak intensity and the thermal expansion coefficient coincidently experience an incipient decrease and then a subsequent increase. The boson peak intensity shows an approximately linear relationship with the thermal expansion coefficient. The thermal expansion can be affected by structural relaxation or rejuvenation, which can reflect the flow units variation and atomic packing of a metallic glass. Our results indicate a direct link between structural relaxation or rejuvenation and fast boson peak dynamics, providing insights into the boson peak behavior and structural heterogeneity of metallic glasses.

关键词： metallic glass thermal expansion boson peak high pressure aging

Highly energetic and flammable metallic glasses

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Science China(Physics,Mechanics & Astronomy) 2020年第7期63卷 68-72页

作者： BangSheng Yu YongHao Sun haiyang bai WeiHua Wang Institute of Physics Chinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBejing 100049China Songshan Lake Materials Laboratory Dongguan 523808China

Energetic materials are solids that release a large amount of energy in combustion. The evaluation depends on both combustion heat and ignition temperature. Conventional non-metallic materials have low ignition temperature but small combustion heat,whereas metals have large combustion heat but high ignition temperatures. We show that many metallic glasses, combining the merits of both metals and non-metals, have large combustion heat, approximately twice that of the non-metals, and low ignition temperature that is several hundreds of Kelvin lower than that of the metals. The ease in igniting metallic glass results from the low thermal conductivity of the materials and the storage of energy in their liquid-like atomic structure. Metallic glass ribbons outweigh metallic nanoparticles due to their high production efficiency, low cost and nontoxicity. The findings suggest that metallic glasses are alternative energetic materials.

关键词： metallic glass energetic particles combustion fast ignition nanoscale materials

Anomalous Specific Heat Behavior of Nanocrystalline Fe at Low Temperatures

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Chinese Physics Letters 1995年第9期12卷 549-552页

作者： bai haiyang LUO Jianlin JIN Duo SUN Jirong Cryogenic Laboratory Chinese Academy of SciencesBeijing 100080 Institute of Physics Chinese Academy of SciencesBeijing 100080

The specific heat of nanocrystalline iron with grain size of 40nm has been measured in the low temperature range from 1.8 to *** anomalous specific heat behavior of nanocrystalline iron is compared to that of the standard bulk *** is found that the electronic specific heat coefficientγobtained at low temperatures decreases by about 50%.A T^(2) term in the heat capacity associated with surface modes has been clearly observed.A large enhancement of the specific heat at temperatures above 16K may be interpreted as the Einstein oscillator contributions.

关键词： grain coefficient heat

Diverse glasses revealed from Chang'E-5 lunar regolith

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National Science Review 2023年第12期10卷 150-163页

作者： Rui Zhao Laiquan Shen Dongdong Xiao Chao Chang Yao Huang Jihao Yu Huaping Zhang Ming Liu Shaofan Zhao Wei Yao Zhen Lu Baoan Sun haiyang bai Zhigang Zou Mengfei Yang Weihua Wang Institute of Physics Chinese Academy of Sciences Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences Qian Xuesen Laboratory of Space Technology China Academy of Space Technology Songshan Lake Materials Laboratory 5. College of Engineering and Applied Sciences Nanjing University China Academy of Space Technology

Lunar glasses with different origins act as snapshots of their formation processes,providing a rich archive of the Moon’s formation and ***,we reveal diverse glasses from Chang’E-5(CE-5) lunar regolith,and clarify their physical origins of liquid quenching,vapor deposition and irradiation damage *** series of quenched glasses,including rotation-featured particles,vesicular agglutinates and adhered melts,record multiple-scale impact *** micro-impact products,like micron-to nano-scale glass droplets or craters,highlight that the regolith is heavily reworked by frequent micrometeorite *** from Apollo samples,the indigenous ultra-elongated glass fibers drawn from viscous melts and the widespread ultra-thin deposited amorphous rims without nanophase iron particles both indicate a relatively gentle impact environment at the CE-5 landing *** clarification of multitype CE-5 glasses also provides a catalogue of diverse lunar glasses,meaning that more of the Moon’ s mysteries,recorded in glasses,could be deciphered in future.

关键词： lunar glasses glass fibers amorphous rims micrometeorite impacts gentle impact environment

Giant enhancement of magnetocaloric effect in metallic glass matrix composite

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Science China(Physics,Mechanics & Astronomy) 2008年第4期51卷 337-348页

作者： WANG YongTian bai haiyang PAN MingXiang ZHAO DeQian WANG WeiHua Institute of Physics Chinese Academy of SciencesBeijing 100080China

The magnetocaloric effect (MCE) has made great success in very low temperature refrigeration, which is highly desirable for application to the extended higher tem-perature range. Here we report the giant enhancement of MCE in the metallic glass composite. The large magnetic refrigerant capacity (RC) up to 103 J·kg-1 is more than double the RC of the well-known crystalline magnetic refrigerant compound Gd5Si2Ge1.9Fe0.1 (357 J·kg-1) and MnFeP0.45As0.55 (390 J·kg-1)(containing either ex-orbitant-cost Ge or poisonous As). The full width at half maximum of the magnetic entropy change (ΔSm) peak almost spreads over the whole low-temperature range (from 303 to 30 K), which is five times wider than that of the Gd5Si2Ge1.9Fe0.1 and pure Gd. The maximum ΔSm approaches a nearly constant value in a wide tem-perature span over 100 K, and however, such a broad table-like region near room temperature has seldom been found in alloys and compounds. In combination with the intrinsic amorphous nature, the metallic glass composite may be potential for the ideal Ericsson-cycle magnetic refrigeration over a broad temperature range near room temperature.

关键词： metallic glass magnetocaloric effect composite

Toward an ideal electrical resistance strain gauge using a bare and single straight strand metallic glassy fiber

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Science China(Physics,Mechanics & Astronomy) 2012年第4期55卷 609-613页

作者： YI Jun HUO LiShan ZHAO DeQian PAN MinXiang bai haiyang WANG WeiHua Institute of Physics Chinese Academy of SciencesBeijing 100190China

Electrical resistance strain gauges(SGs) are useful tools for experimental stress analysis and the strain sensing elements in many electromechanical transducers including load cells,pressure transducers,torque meters,accelerometers,force cells,displacement transducers and so *** commonly used commercial crystalline strain sensing materials of SGs are in the form of wire or foil of which performance and reliability is not good enough due to their low electrical resistivity and incapacity to get thin *** SGs with single straight strand strain sensing materials,which are called ideal SG,are highly desirable for more than seven decades since the first SG was ***,we show the development of a type of minuscule length scale strain gauge by using a bare and single straight strand metallic glassy fiber(MGF) with high resistivity,much smaller lengthscale,high elastic limits(2.16%) and especially the super piezoresistance *** anticipate that our metallic glassy fiber strain gauge(MGFSG),which moves toward the ideal SGs,would have wide applications for electromechanical transducers and stress analysis and catalyze development of more micro-and nanoscale metallic glass applications.

关键词：电阻应变计金属玻璃理想纤维直链实验应力分析机电传感器传感材料

Glassy metallic plastics

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Science China(Physics,Mechanics & Astronomy) 2010年第3期53卷 409-414页

作者： LI JianFu, WANG JunQiang, LIU XiaoFeng, ZHAO Kun, ZHANG Bo, bai haiyang, PAN MingXiang & WANG WeiHua Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China Institute of Physics Chinese Academy of Sciences Beijing China

This paper reports a class of bulk metallic glass including Ce-, LaCe-, CaLi-, Yb-, and Sr-based metallic glasses, which are regarded as glassy metallic plastics because they combine some unique properties of both plastics and metallic alloys. These glassy metallic plastics have very low glass transition temperature (Tg^25oC to 150oC) and low Young’s modulus (~20 GPa to 35 GPa). Similar to glassy plastics, these metallic plastics show excellent plastic-like deformability on macro-, micro- and even nano-scale in their supercooled liquid range and can be processed, such as elongated, compressed, bent, and imprinted at low temperatures, in hot water for instance. Under ambient conditions, they display such metallic properties as high thermal and electric conductivities and excellent mechanical properties and other unique properties. The metallic plastics have potential applications and are also a model system for studying issues in glass physics.

关键词： glassy metallic plastic synthesizing low Tg thermoplastic properties

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农业基础设施对粮食生产效率的影响

华东经济管理 2022年第10期36卷 100-109页

作者：张志新李成白海洋山东理工大学经济学院山东淄博255049 东北农业大学经济管理学院黑龙江哈尔滨150030

文章基于农业基础设施类型差异视角,以2000—2019年省级面板数据为基础,使用动态面板两步差分GMM和双重中介效应的方法,探究了不同类型农业基础设施对粮食生产效率的影响以及作用机制。研究结果表明:总体上,农业基础设施对粮食生产效率... 详细信息

文章基于农业基础设施类型差异视角,以2000—2019年省级面板数据为基础,使用动态面板两步差分GMM和双重中介效应的方法,探究了不同类型农业基础设施对粮食生产效率的影响以及作用机制。研究结果表明:总体上,农业基础设施对粮食生产效率有正向影响,但不同类型农业基础设施对粮食生产效率的影响存在明显的差异性,其影响程度依次为农业水利基础设施、交通基础设施、数字基础设施和电力基础设施。进一步通过机制分析发现:一方面,农业基础设施通过提高粮食生产过程中技术水平,从而降低单位粮食生产资源消耗,提高粮食生产效率;另一方面,农业基础设施通过扩大粮食生产规模程度,从而提高粮食生产机械化水平,提升粮食生产效率。

关键词：农业基础设施粮食生产效率技术效应规模效应

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Irradiation Induced Amorphization and Free Enengy Calculation in Immiscible Fe-Cu Multilayers

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Chinese Physics Letters 1993年第9期10卷 531-534页

作者： bai haiyang LIU baixin Department of Materials Science and Engineering Tsinghua UniversityBeijing 100084

Amorphization was achieved by a *** process of ion mixing of multilayered films iii an inuniscible Fe-Cu system with a large positive heat of formation(+19kJ/mol).The free energy diagrtiin of the Fe-Cu system was *** calculation,the inter facial free energy,ferromugnctic effect and the structure ch arac-tenstics were *** calculated Fe-Cu free energy diagram can explain the ainorphization behavior in this imniiscible system.

关键词： system diagram mixing