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Pressure evolution of the Magnetism and Fermi Surface of ybPtBi Probed by a Tunnel Diode Oscillator Based Method

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Chinese Physics Letters 2022年第9期39卷 41-46页

作者： y.e.Huang F.Wu A.Wang y.Chen L.Jiao M.Smidman H.Q.yuan Center for Correlated Matter and Department of Physics Zhejiang UniversityHangzhou 310058China Zhejiang Province Key Laboratory of Quantum Technology and Device Department of PhysicsZhejiang UniversityHangzhou 310058China State Key Laboratory of Silicon Materials Zhejiang UniversityHangzhou 310058China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

A central research topic in condensed matter physics is the understanding of the evolution of various phases and phase transitions under different tuning parameters such as temperature, magnetic field and pressure. To explore the pressure-induced evolution of the magnetism and Fermi surface of the heavy fermion antiferromagnet yb Pt Bi, we performed tunnel diode oscillator based measurements under pressure at low temperatures in high magnetic fields. Our results reveal that the magnetic order strengthens and the Fermi surface shrinks as the pressure increases, which are consistent with typical observations for yb-based heavy fermion compounds. In addition, an anomalous change in the quantum oscillation amplitudes is observed above 1.5 GPa, and determining the origin requires further study.

关键词： Fermi Probe oscillation

Solid Desiccant Dehumidification Techniques Inspired from Natural electroosmosis Phenomena

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Journal of Bionic engineering 2011年第1期8卷 90-97页

作者： B. Li y. y. yan Faculty of engineering University of Nottingham Lenton Firs Building University Park Nottingham NG7 2RD UK

electroosmosis has been shown to be an effective means of different applications in various fields such as Micro-electro-Mechanical systems （MeMS） and biomimetics applications. This paper aims to prove the concept that the electroosmosis phenomena can also be cooperated into larger scale applications in the building service industry like dehumidification or damping proof. The electroosmotic flow inside a porous medium is validated experimentally to further understand the dehumidification mechanism of combined techniques. An experimental test validates that the condensation from the porous medium can be obtained by electroosmotic force generated by external electric field, especially for specific desiccant powders like zeolite and diatomaceous earth. With a range of volts from 5 V to 20 V applying between the testing plates, the maximum flow rate through the cross section in the testing plate achieved during the peak period is 1.35 laL＇min 1. These promising phenomena can act as an alternative way for energy choice in dehumidification industrial field. Further researches on new regeneration methods for solid desiccant dehumidification are required to make the system simple, energy-saving and suitable for small air conditioning units.

关键词： biomimetics electroosmotic flow solid desiccant dehumidification

Friction stir spot welding of SPCC low carbon steel plates at extremely low welding temperature

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Journal of Materials Science & Technology 2019年第5期35卷 733-741页

作者： y.F.Sun H.Fujii y.Sato y.Morisada Joining and Welding Research Institute Osaka University 11-1 Mihogaoka Ibaraki 567-004Japan School of Materials Science and engineering Zhengzhou University Zhengzhou 450001 China

Friction stir spot welding (FSSW) was applied to 2.0 mm thick steel plate cold-rolled commercial (SPCC) low carbon steel plates at a very low rotation speed that ranged from 5 to 50rpm, which was much lower than that generally used for the conventional FSSW technique. Due to the very low heat input, the welding processes could therefore be completed at a peak welding temperature below 160℃. As a result, a significantly refined microstructure with an average grain size of about 0.41μm was formed in the stir zone of the joints and the JI {0-11 } and J2{1-1O} shear textures were the dominant components, which are different from the D1{11-2} and D2{-1-12} shear textures formed in the conventional FSSW joints. In addition, no heat affected zone could be detected along the crosssectional plane of the joints. Although a few void-like non-bonded areas were still observed along the interface between the upper and lower steel plates, the shear tensile loads of the joints increased to about 10.0 kN when welded at a condition of 8t, 20rpm and 30 s, and the joints fractured through the plug failure mode.

关键词： Friction stir spot welding Dynamic recrystallization Microstructure Steel

Improvement of Input Power Dynamic Range for Wavelength Converters Based on Cross-Gain Modulation

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光学学报 2003年第S1期23卷 489-490页

作者： Joon-Hak Bang je-Soo Ko electronics and Telecommunications Research Institute KoreaElectronics and Telecommunications Research Institute Korea

A technique for improving the input power dynamic range of wavelength converters based on cross-gain modulation in a semiconductor optical amplifier is presented.

关键词： of In as be for SOA

Therapeutic potential of exercise-hormone irisin in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1555-1564页

作者： eunhee Kim Rudolph eTanzi Se Hoon Choi Genetics and Aging Research Unit MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMAUSA McCance Center for Brain Health Massachusetts General HospitalBostonMAUSA

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type Ⅲ domain-containing protein 5(FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-β and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-β pathology by increasing the activity/levels of amyloid-β-degrading enzyme neprilysin secreted from astrocytes. Herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

关键词： Alzheimer's disease exercise fibronectin typeⅢdomain-containing protein 5(FNDC5) irisin

Active elastic metamaterials for subwavelength wave propagation control

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Acta Mechanica Sinica 2015年第3期31卷 349-363页

作者： y.y.Chen G.L.Huang Department of Mechanical and Aerospace engineering University of Missouri

Recent research activities in elastic metamaterials demonstrate a significant potential for subwavelength wave propagation control owing to their interior locally resonant mechanism. The growing technological developments in electro/magnetomechanical couplings of smart materials have introduced a controlling degree of freedom for passive elastic metamaterials. Active elastic metamaterials could allow for a fine control of material physical behavior and thereby induce new functional properties that cannot be produced by passive approaches. In this paper, two types of active elastic metamaterials with shunted piezoelectric materials and electrorheological elastomers are proposed. Theoretical analyses and numerical validations of the active elastic metamaterials with detailed microstructures are pre- sented for designing adaptive applications in band gap structures and extraordinary waveguides. The active elastic metamaterial could provide a new design methodology for adaptive wave filters, high signal-to-noise sensors, and structural health monitoring applications.

关键词： Active elastic metamaterials Subwavelengthwave control Adaptive metastructures Smart materials

Microstructure and mechanical properties of TiAl/TiAl joints brazed with a newly developed Ti–Ni–Nb–Zr quaternary filler alloy

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Progress in Natural Science:Materials International 2022年第6期32卷 758-768页

作者： H.S.Ren y.L.Shang X.y.Ren y.J.Jing H.P.Xiong y.y.Cheng Welding and Plastic Forming Division Beijing Institute of Aeronautical Materials

A novel Ti-Ni-Nb-Zr quaternary filler alloy with the composition of Ti-(19～25)Ni-(15～25)(Nb+Zr)(wt.%) was *** filler alloy was composed of(Ti,Nb)ss,(Ti,Zr,Nb)ss+(Ti,Zr)2Ni,α-Ti and Ti2Ni *** was fabricated into filler foil with a thickness of about 45 μm by a rapid solidification *** results indicate that the liquidus temperature of the Ti-Ni-Nb-Zr brazing alloy was about 978℃,and the brazing alloy presented excellent wettability on TiAl *** TiAl joint mainly consisted of β/B2 phase,Ti2Al,Ti2AlNi and α2-Ti3Al *** diffusion of Al atom from base metal to brazed seam led to the formation of Ti2Al and *** that no previously references on XRD pattern of Ti2AlNi compound can be found,Ti2AlNi cast alloy specimen was specially prepared and XRD peaks were specially *** micro-hardness and bending strength tests of the Ti2AlNi phase were carried out,and the results were 761 HV and 192 MPa,*** brazing parameters of 1010 ℃/10 min offered the joint shear strength of 280 MPa at room temperature,and the joints exhibited tensile strength of 372 MPa at room temperature and 340 MPa at 750 ℃,indicating that the newly developed filler alloy could offer a stable high-temperature strength.

关键词： TiAl Brazing Filler alloy Microstructure Mechanical properties

NUMeRICAL SIMULATION OF eXTRUSION OF COMPOSITe POWDeRS PRePAReD By HIGH eNeRGy MILLING

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Acta Metallurgica Sinica(english Letters) 2004年第1期17卷 51-54页

作者： X.Q.Li W.P.Chen W.Xia Q.L.Zhu y.y.Li e.D.Wang College of Mechanical engineering South China University of Technology.Guangzhou 510640 China School of Materials Science and engineering Harbin Institute of Technology Harbin 150001 China

Based on the characteristic of high energy milling and the micromechanics of composite material, a plastic constitutive equation is implemented for milled composite powders. To check the equation, the extrusion of Ti/Al composite powders prepared by high energy milling was simulated. It was from the numerical analysis that the predicted extrusion pressure mounted up with milling time and extrusion ratio increasing, which was perfect agreement with experimental results.

关键词： high energy milling composite powder plastic constitutive equation extrusion numerical simulation

Reduction of structural response to near fault earthquakes by seismic isolation columns and variable friction dampers

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earthquake engineering and engineering Vibration 2010年第1期9卷 113-122页

作者： y.Ribakov Department of Civil engineering Ariel University Center of Samaria

This paper focuses on the investigation of a hybrid seismic isolation system with passive variable friction dampers for protection of structures against near fault earthquakes. The seismic isolation can be implemented by replacing the conventional columns fixed to the foundations by seismic isolating ones. These columns allow horizontal displacement between the superstructure and the foundations and decouple the building from the damaging earthquake motion. As a result, the forces in the structural elements decrease and damage that may be caused to the building by the earthquake significantly decreases. However, this positive effect is achieved on account of displacements occurring in the isolating columns. These displacements become very large when the structure is subjected to a strong earthquake. In this case, impact may occur between the parts of the isolating column yielding their damage or collapse. In order to limit the displacements in the isolating columns, it is proposed to add variable friction dampers. A method for selecting the dampers＇ properties is proposed. It is carried out using an artificial ground motion record and optimal active control algorithm. Numerical simulation of a sevenstory structure shows that the proposed method allows efficient reduction in structural response and limits the displacements at the seismic isolating columns.

关键词： seismic isolating columns variable friction dampers hybrid seismic isolation near fault earthquakes control algorithm