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Tuning thermal expansion by a continuing atomic rearrangement mechanism in a multifunctional titanium alloy

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Journal of Materials Science & Technology 2021年第21期80卷 234-243页

作者： D.l.Gong H.l.Wang E.G.Obbard S.J.li R.yang y.l.hao Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang110016China School of Mechanical Engineering Dongguan University of TechnologyDongguan523808China Department of Electrical Engineering and Telecommunications University of New South WalesSydneyNSW2052Australia

As to multifunctional titanium alloys with high strength and low elastic modulus, thermal training is crucial to tune their thermal expansion from positive to negative, resulting in a novel linear expansion which is stable in a wide temperature range. Aided by the high-order Hooke's law of elastic solids,a reversible atomic rearrangement mechanism was proposed to explain the novel findings which are unexpected from typical shape memory alloys. To confirm this continuous mechanism, a Ti-Nb based alloy, which possesses a nanoscale spongy microstructure consisting of the interpenetrated Nb-rich and Nb-lean domains produced by spinodal decomposition, was used to trace the crystal structure change by in-situ high energy synchrotron X-ray diffraction analyses. By increasing exposure time, the overlapped diffraction peaks can be separated accurately. The calculated results demonstrate that, in the nanoscale Nb-lean domains, the crystal structure parameters vary linearly with changing temperature along the atomic pathway of the bcc-hcp transition. This linear relationship in a wide temperature range is unusual for first-order martensitic shape memory alloys but is common for Invar alloys with high-order spin transitions. Furthermore, the alloy exhibits smooth DSC curves free of transformation-induced heat peaks observed in shape memory alloys, which is consistent with the proposed mechanism that the reversible transition is of high-order.

关键词： Coefficient of thermal expansion Multifunctional titanium alloys Spongy microstructure Atomic rearrangement Elastic anisotropy

Ordering-induced Elinvar effect over a wide temperature range in a spinodal decomposition titanium alloy

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Journal of Materials Science & Technology 2023年第19期150卷 245-255页

作者： D.l.Gong H.l.Wang S.H.hao P.liu X.yang y.N.Jiang W.J.Wang K.lin B.li K.Du y.D.Wang R.yang y.l.hao Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Analysis and Testing Center Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Beijing Advanced Innovation Center for Materials Genome Engineering Institute of Solid State ChemistryDepartment of Physical ChemistryUniversity of Science and Technology BeijingBeijing 100083China State Key laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

Temperature-independent elastic modulus is termed as Elinvar effect,which is available by tuning the continuous spin transition of ferromagnetic alloys via composition optimization and the first-order martensitic transformation of shape memory alloys via plastic ***,these reversible mechanisms are restricted generally in a narrow temperature range of less than 300 *** reports,by tuning a spinodal decomposition in a Ti-Nb-based titanium alloy via aging treatment,both the Elinvar effect in a wide temperature range of about 500 K and a high strength-to-modulus ratio of about 1.5%can be obtained by a continuous and reversible crystal ordering *** results demonstrate that the alloy aged at 723 K for 4 h has a nanoscale plate-like modulatedβ+α"two-phase microstructure and its elastic modulus keeps almost constant from 100 to 600 *** and in-situ X-ray diffraction measurements reveal that the crystal ordering parameter of theα"phase increases linearly with temper-ature from 0.88 at 133 K to 0.97 at 523 K but its volume fraction keeps a constant of about 33.8%.This suggests that the continuous ordering of theα"phase toward the high modulusαphase induces a posi-tive modulus-temperature relation to balance the negative relation of the elastically stableβ*** aged alloy exhibits a high yield strength of 1200 MPa,good ductility of 16%and a high elastic admissible strain of 1.5%.Our results provide a novel strategy to extend the Elinvar temperature range and enhance the strength by tuning the crystal ordering of decomposition alloys.

关键词： Titanium alloy Spinodal decomposition Crystal ordering Elinvar effect Mechanical properties

Microstructures and Hardness Properties for β-Phase Ti-24Nb-4Zr-7.9Sn Alloy Fabricated by Electron Beam Melting

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Journal of Materials Science & Technology 2013年第11期29卷 1011-1017页

作者： J.Hernandez S.J.li E.Martinez l.E.Murr X.M.Pan K.N.Amato X.y.Cheng F.yang C.A.Terrazas S.M.Gaytan y.l.hao R.yang F.Medina R.B.Wicker Department of Metallurgical and Materials Engineering The University of Texas at El Paso Shenyang National laboratory for Materials Science Institute of Metal ResearchChinese Academy of Sciences School of Materials Science and Engineering Dalian University of Technology W.M.Keck Center for 3D Innovation The University of Texas at E1 Paso

Atomized, pre-alloyed Ti-24Nb-4Zr-7.9Sn （wt%） powder was used to fabricate solid, prototype components by electron beam melting （EBM）. Vickers microindentation hardness values were observed to average 2 GPa for the precursor powder and 2.5 GPa for the solid, EBM-fabricated products. The powder and solid product microstructures were examined by optical and electron microscopy. X-ray diffraction analyses showed that they had bcc β-phase microstructure. However, it was found by transmission electron microscopy that the EBM-fabricated product had plate morphology with space -100-200 nm. Although the corresponding selected area diffraction patterns can be indexed by β-phase plus α＂-martensite with orthorhombic crystal structure, the dark-field analyses failed to observe the α＂-martensite. Such phenomenon was also found in deformed gum metals and explained by stress-induced diffusion scattering due to phonon softening.

关键词： Biomedical titanium alloy β-Martensite Electron beam melting Hardness Optical and electron microscopy

Variational data encoding and correlations in quantum-enhanced machine learning

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Chinese Physics B 2024年第9期33卷 298-306页

作者： Ming-hao Wang Hua l¨u School of Physics Hubei UniversityWuhan 430062China School of Science Hubei University of TechnologyWuhan 430068China

leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical *** paper tackles two pivotal challenges in the realm of quantum computing:firstly,the development of an effective encoding protocol for translating classical data into quantum states,a critical step for any quantum *** encoding strategies can significantly influence quantum computer ***,we address the need to counteract the inevitable noise that can hinder quantum *** primary contribution is the introduction of a novel variational data encoding method,grounded in quantum regression algorithm *** adapting the learning concept from machine learning,we render data encoding a learnable *** allowed us to study the role of quantum correlation in data *** numerical simulations of various regression tasks,we demonstrate the efficacy of our variational data encoding,particularly post-learning from instructional ***,we delve into the role of quantum correlation in enhancing task performance,especially in noisy *** findings underscore the critical role of quantum correlation in not only bolstering performance but also in mitigating noise interference,thus advancing the frontier of quantum computing.

关键词： quantum machine learning variational data encoding quantum correlation

Enhancing force sensing in a squeezed optomechanical system with quantum nondemolition measurement

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Communications in Theoretical Physics 2024年第1期76卷 49-60页

作者： Shi-lei Chao Zi-hao li Xin-you lü School of Physics Huazhong University of Science and Technology430074 WuhanChina

A theoretical scheme is proposed to enhance the sensitivity of force sensors with quantum nondemolition measurement(QND)in an optomechanical setup assisted by four-tone optical driving and an optical parametric amplifier(OPA).With the help of special drive,the system can be simplified as the typical type of QND for force sensing,so that the backaction noise can be evaded to surpass the standard quantum ***,the added noise can be suppressed owing to the modified optical susceptibility resulting from the *** introducing two oscillators coupling with two charged bodies respectively,the signal can be enhanced with the nonlinearity caused by Coulomb interaction,while the noise presents an exponential ***,considering the homodyne detection effect,the range of system parameters and frequency bands will be *** present investigation may provide a route toward simultaneously evading backaction noise,reducing the mechanical thermal noise,and enhancing the external signal,which can be an alternative design for sensitive devices.

关键词： force sensing optical parametric amplifier quantum non-demolition measurement optomechanical system

Nonreciprocal generation of Schrodinger cat state induced by topology

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 23-30页

作者： Zi-hao li li-li Zheng ying Wu Xin-you lü School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and Technologyand Wuhan Institute of Quantum TechnologyWuhan 430074China Key laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education Jianghan UniversityWuhan 430074China

The Schrodinger cat state produced differently in two directions is anticipated to be a critical quantum resource in quantum information *** exploring the interplay between quantum nonreciprocity and topology in a one-dimensional microcavity array,we obtain the Schrodinger cat state(a pure quantum state)in a chosen direction at the edge cavity,whereas a classical state in the other *** nonreciprocal generation of the cat state originates from the topologically protected chiralitymode excitation in the nontrivial phase,but in the trivial phase,the nonreciprocal generation of cat state ***,our proposal is switchable by tuning the parameters so that a topological phase transition ***,the obtained cat state has nonreciprocal high fidelity,nonclassicality,and quantum coherence,which are sufficient to be used in various one-way quantum technologies,e.g.,invisible quantum sensing,noise-tolerant quantum computing,and chiral quantum *** work provides a general approach to control quantum nonreciprocities with the topological effect,which substantially broadens the fields of nonreciprocal photonics and topological physics.

关键词： Schr?dinger cat state nonreciprocity topology

Effect of CO_(2) Opposing Multiple Jets on Thermoacoustic Instability and NO_(x) Emissions in a lean-Premixed Model Combustor

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Journal of Thermal Science 2024年第1期33卷 207-221页

作者： ZHOU hao HU liubin Institute for Thermal Power Engineering State Key Laboratory of Clean Energy UtilizationZhejiang UniversityHangzhou 310027China

This paper experimentally studied the effect of CO_(2) opposing multiple jets on the thermoacoustic instability and NO_(x) emissions in a lean-premixed model *** feasibility was verified from three variables:the CO_(2) jet flow rate,hole numbers,and hole diameters of the *** indicate that the control effect of thermoacoustic instability and NO_x emissions show a reverse trend with the increase of open area ratio on the whole,and the optimal jet flow rate range is 1-4 l/min with CO_(2) opposing multiple *** this flow rate range,the amplitude and frequency of the dynamic pressure and heat release signals CH~* basically decrease as the CO_(2) flow rate increases,which avoids high-frequency and high-amplitude thermoacoustic *** amplitude-damped ratio of dynamic pressure and CH*can reach as high as 98.75% and 93.64% with an optimal open area ratio of 3.72%.NO_(x) emissions also decrease as the jet flow rate increases,and the maximum suppression ratio can reach 68.14%.Besides,the flame shape changes from a steep inverted "V" to a more flat "M",and the flame length will become shorter with CO_(2) opposing multiple *** research achieved the synchronous control of thermoacoustic instability and NO_(x) emissions,which could be a design reference for constructing a safer and cleaner combustor.

关键词： thermoacoustic instability lean-premixed model combustor CO_(2)opposing multiple jets open area ratio NO_(x)emissions

Electrode particulate materials for advanced rechargeable batteries:A review

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Particuology 2024年第3期86卷 160-181页

作者： Mingyang Ma Miao Du yan liu Hongyan lü Jialin yang Zelin hao Jinzhi Guo Xinglong Wu MOE Key laboratory for UV light-Emitting Materials and Technology Northeast Normal UniversityChangchunJilin130024China Department of Chemistry Northeast Normal UniversityChangchunJilin130024China

The demand for large-scale energy storage is increasing due to the decreasing non-renewable resources and deteriorating environmental *** rechargeable batteries with high energy density and long cycle performance is an ideal choice to meet the demand of energy storage *** development of excellent electrode particles is of great significance in the commercialization of nextgeneration *** ideal electrode particles should balance raw material reserves,electrochemical performance,price and environmental *** them,the development of electrode particulate materials with excellent electrochemical properties is the top priority at *** this review,the typical researches of electrode materials are summarized in terms of crystal structure,morphology,pore structure,surface and interface ***,the structural characteristics and improvement methods of transition metal oxides,polyanionic compounds,Prussian blue and their analogues are ***,the different effects of particulate morphology,pore,surface and interface structure on the performance of electrode materials are *** designing high-performance electrode materials,preparation route should be set according to the particle properties of the materials and the synergistic effect of various optimization methods should be *** the same time,in addition to the electrode materials,other components of the rechargeable batteries,such as current collector,separator and electrolytes,should be optimized to improve the overall performance of the *** review would provide important guiding principle for designing high-performance electrode particulate materials.

关键词： Particulate properties Electrode materials Rechargeable batteries

Morphology and phylogenetic placement of Mallomonas vietnamica(Synurales,Chrysophyceae)from China

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Journal of Oceanology and limnology 2024年第4期42卷 1325-1335页

作者： Junxue hao Fangru NAN Junping lÜ Qi lIU Xudong lIU Shulian XIE Jia FENG School of life Science Shanxi UniversityTaiyuan 030006China

The newly described chrysophyte,Mallomonas vietnamica,is reported for the first time in China from specimens collected in Guizhou Province,SW *** morphological characteristics were studied using light and scanning electron *** species was described based on morphological characteristics,including cell size,scale size,dome,V-rib,and ***,molecular sequencing of *** was conducted and a phylogenetic tree was constructed based on concatenated SSU,lSU,and rbc l *** phylogenetic tree led us to suggest raising a new section named Uncatusipedae for this *** study provides new molecular data from the genus Mallomonas and enriches our understanding of the species diversity and geographical distribution of the genus Mallomonas in China.

关键词： Chrysophyta Mallomonas vietnamica phylogenetic study taxonomy