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Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix composites by crystal plasticity finite element method

中国会计学会2007年学术年会

作者： Tracey Rui Hua jiang lana y. j. liu Simon Hussain Lecturer in Accounting and Finance Newcastle University Business School Newcastle University

It has been documented in prior studies that Chinese companies issuing both A-shares （domestic investors） and B-shares （foreign investors） often report earnings numbers under Chinese GAAP that are notably different from their IAS *** has been cited as evidence of failure in China’s attempts to harmonize their accounting standards with IAS,and that Chinese GAAP earnings numbers may have been ’managed’ upwards because Chinese managers’ incentives are primarily built around Chinese GAAP data,rather then IAS data （***,et al.2002）.However,since the start of 2001,China’s new Accounting Standard for Business Enterprises has been in effect: we provide some of the first empirical evidence on how this new regulation has impacted the China-IAS earnings *** employ both graphical analysis and multivariate regression models to a set of 198 firm-year observations for B-share firms on the Shanghai Stock Exchange for the period *** find evidence of the earnings gap being notably reduced in the years immediately following 2001,consistent with improved de facto *** also find evidence that the earnings gap is significantly greater in those cases where we may expect there to be incentives for earnings management,following US evidence （Burgstahler and Dichev,1997）.That is to say,having controlled for a declining time trend in the mean earnings gap during 2000-03 we find evidence of a significant positive bias in Chinese GAAP earnings in cases where firms make ’manageable’ losses or where earnings are declining.

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journal of Materials Science & Technology 2024年第2期169卷 53-67页

作者： y.B.Zhang S.j.Song F.liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&Testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based constitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co-deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix composites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple compressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered composites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always accompanied by high-stress concentration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb composites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional combination in strength and *** hetero-phase interface chosen by a couple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic correlation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based constitutive modeling Hetero-phase interface Crystal plasticity finite element

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/CdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.y.Huang Z.yang S.y.yang Z.H.Dai y.j.liu j.H.Liao G.y.Zhong Z.j.Xie y.P.Fang S.S.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/CdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)CdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of CdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

Artificial-intelligent-powered safety and efficiency improvement for controlling and scheduling in integrated railway systems

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High-speed Railway 2024年第3期2卷 172-179页

作者： liu j. liu G. Wang y. Zhang W. Beijing National Railway Research & Design Institute of Signal & Communication Group Co. Ltd Beijing 100070 China Engineering Research Center of Railway Industry of Intelligent and Autonomous Train Control Beijing 100070 China

The multi-mode integrated railway system, anchored by the high-speed railway, caters to the diverse travel requirements both within and between cities, offering safe, comfortable, punctual, and eco-friendly transportation services. With the expansion of the railway networks, enhancing the efficiency and safety of the comprehensive system has become a crucial issue in the advanced development of railway transportation. In light of the prevailing application of artificial intelligence technologies within railway systems, this study leverages large model technology characterized by robust learning capabilities, efficient associative abilities, and linkage analysis to propose an Artificial-intelligent (AI)-powered railway control and dispatching system. This system is elaborately designed with four core functions, including global optimum unattended dispatching, synergetic transportation in multiple modes, high-speed automatic control, and precise maintenance decision and execution. The deployment pathway and essential tasks of the system are further delineated, alongside the challenges and obstacles encountered. The AI-powered system promises a significant enhancement in the operational efficiency and safety of the composite railway system, ensuring a more effective alignment between transportation services and passenger demands. © 2024 Beijing jiaotong University

关键词： Artificial intelligence High-speed railway Large-scale mode, system framework Multi-mode railway system Safety and efficiency improvement

Interfacial stress engineering toward enhancement of ferroelectricity in Al doped HfO_(2)thin films

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Chinese Physics B 2024年第9期33卷 637-643页

作者： S X Chen M M Chen y liu D W Cao G j Chen Department of Microelectronics Jiangsu UniversityZhenjiang 212013China Department of Physics Jiangsu UniversityZhenjiang 212013China Guangdong–Hong Kong–Macao joint Laboratory for Intelligent Micro-Nano Optoelectronic Technology Foshan UniversityFoshan 528225China

Ferroelectric HfO_(2)has attracted much attention owing to its superior ferroelectricity at an ultra-thin thickness and good compatibility with Si-based complementary metal-oxide-semiconductor(CMOS)***,the crystallization of polar orthorhombic phase(o-phase)HfO_(2)is less competitive,which greatly limits the ferroelectricity of the as-obtained ferroelectric HfO_(2)thin ***,the crystallization of o-phase HfO_(2)can be thermodynamically modulated via interfacial stress *** this paper,the growth of improved ferroelectric Al doped HfO_(2)(HfO_(2):Al)thin films on(111)-oriented Si substrate has been *** analysis has suggested that nonpolar monoclinic HfO_(2):Al grown on(111)-oriented Si substrate suffered from a strong compressive strain,which promoted the crystallization of(111)-oriented o-phase HfO_(2)in the as-grown HfO_(2):Al thin *** addition,the in-plane lattice of(111)-oriented Si substrate matches well with that of(111)-oriented o-phase HfO_(2),which further thermally stabilizes the o-phase HfO_(2).Accordingly,an improved ferroelectricity with a remnant polarization(2P_(r))of 26.7C/cm^(2) has been *** results shown in this work provide a simple way toward the preparation of improved ferroelectric HfO_(2)thin films.

关键词： improved ferroelectricity interfacial stress engineering compressive strain HfO_(2)

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-y alloys with adjusting y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.liu S.j.liu B.Wang W.B.Sun X.j.liu Z.W.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xy alloys with different phase compositions were prepared by various y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-y and describe the details of the second *** tests were performed at room temperature(RT),200℃,and 300℃to study the impact of the y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high y content promotes a microstructure refinement and increases the volume fraction of the second *** the y content increases,different Mg-Zn-y ternary phases appear:I-phase(Mg_(3)Zn_(6)y),W-phase(Mg_(3)Zn_(3)y_(2)),and LPSO phase(Mg_(12)Zny).When the y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at RT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the y *** addition,the compressive deformation behaviors of the porous Mg-Zn-y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium Rare earth elements Microstructure Compressive behavior Energy absorption characteristic

Effect of Al_(2)O_(3)on the Mechanical Properties of(B_(4)C+Al_(2)O_(3))/Al Neutron Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： j.X.Cai B.M.Shi N.Li y.liu Z.G.Zhang y.N.Zan Q.Z.Wang B.L.Xiao Z.y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)O_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)O_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)O_(3)content on the tensile properties of(B_(4)C+Al_(2)O_(3))/Al *** was found that the pinning effect of Al_(2)O_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)O_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)O_(3))/Al composites High-temperature strength

STCF conceptual design report (Volume 1): Physics & detector

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Frontiers of physics 2024年第1期19卷 1-154页

作者： M.Achasov X.C.Ai L.P.An R.Aliberti Q.An X.Z.Bai y.Bai O.Bakina A.Barnyakov V.Blinov V.Bobrovnikov D.Bodrov A.Bogomyagkov A.Bondar I.Boyko Z.H.Bu F.M.Cai H.Cai j.j.Cao Q.H.Cao X.Cao Z.Cao Q.Chang K.T.Chao D.y.Chen H.Chen H.X.Chen j.F.Chen K.Chen L.L.Chen P.Chen S.L.Chen S.M.Chen S.Chen S.P.Chen W.Chen X.Chen X.F.Chen X.R.Chen y.Chen y.Q.Chen H.y.Cheng j.Cheng S.Cheng T.G.Cheng j.P.Dai L.y.Dai X.C.Dai D.Dedovich A.Denig I.Denisenko j.M.Dias D.Z.Ding L.y.Dong W.H.Dong V.Druzhinin D.S.Du y.j.Du Z.G.Du L.M.Duan D.Epifanov y.L.Fan S.S.Fang Z.j.Fang G.Fedotovich C.Q.Feng X.Feng y.T.Feng j.L.Fu j.Gao y.N.Gao P.S.Ge C.Q.Geng L.S.Geng A.Gilman L.Gong T.Gong B.Gou W.Gradl j.L.Gu A.Guevara L.C.Gui A.Q.Guo F.K.Guo j.C.Guo j.Guo y.P.Guo Z.H.Guo A.Guskov K.L.Han L.Han M.Han X.Q.Hao j.B.He S.Q.He X.G.He y.L.He Z.B.He Z.X.Heng B.L.Hou T.j.Hou y.R.Hou C.y.Hu H.M.Hu K.Hu R.j.Hu W.H.Hu X.H.Hu y.C.Hu j.Hua G.S.Huang j.S.Huang M.Huang Q.y.Huang W.Q.Huang X.T.Huang X.j.Huang y.B.Huang y.S.Huang N.Hüsken V.Ivanov Q.P.ji j.j.jia S.jia Z.K.jia H.B.jiang j.jiang S.Z.jiang j.B.jiao Z.jiao H.j.jing X.L.Kang X.S.Kang B.C.Ke M.Kenzie A.Khoukaz I.Koop E.Kravchenko A.Kuzmin y.Lei E.Levichev C.H.Li C.Li D.y.Li F.Li G.Li G.Li H.B.Li H.Li H.N.Li H.j.Li H.L.Li j.M.Li j.Li L.Li L.Li L.y.Li N.Li P.R.Li R.H.Li S.Li T.Li W.j.Li X.Li X.H.Li X.Q.Li X.H.Li y.Li y.y.Li Z.j.Li H.Liang j.H.Liang y.T.Liang G.R.Liao L.Z.Liao y.Liao C.X.Lin D.X.Lin X.S.Lin B.j.liu C.W.liu D.liu F.liu G.M.liu H.B.liu j.liu j.j.liu j.B.liu K.liu K.y.liu K.liu L.liu Q.liu S.B.liu T.liu X.liu y.W.liu y.liu y.L.liu Z.Q.liu Z.y.liu Z.W.liu I.Logashenko y.Long C.G.Lu j.X.Lu N.Lu Q.F.Lü y.Lu y.Lu Z.Lu P.Lukin F.j.Luo T.Luo X.F.Luo y.H.Luo H.j.Lyu X.R.Lyu j.P.Ma P.Ma y.Ma y.M.Ma F.Maas S.Malde D.Matvienko Z.X.Meng R.Mitchell A.Nefediev y.Nefedov S.L.Olsen Q.Ouyang P.Pakhlov G.Pakhlova X.Pan y.Pan E.Passemar y.P.Pei H.P.Peng L.Peng X.y.Peng X.j.Peng K.Peters S.Pivovarov E.Pyata B.B.Qi y.Q.Qi W.B.Qian y.Qian C.F.Qiao j.j.Qin j.j.Qin L.Q.Qin X.S.Qin T.L.Qiu j.Rademacker C.F.Redmer H.y.Sang Anhui University Hefei 230039China Beihang University Beijing 100191China Budker Institute of Nuclear Physics Novosibirsk 630090Russia CAS Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Cavendish Laboratory University of CambridgeJJ Thomson AveCambridge CB30HEUnited Kingdom Central China Normal University Wuhan 430079China Central South University Changsha 410083China China University of Geosciences Wuhan 430074China China University of Mining and Technology Xuzhou 221116China École Polytechnique Fédérale de Lausanne(EPFL) LausanneSwitzerland Fudan University Shanghai 200433China Goethe University Frankfurt D-60325 Frankfurt am MainGermany Guangxi Normal University Guilin 541004China Guangxi Uninversity Nanning 530004China Hangzhou Institute for Advanced Study UCASHangzhou 310024China Hebei Normal University Shijiazhuang 050024China Hebei University Baoding 071002China Hefei University of Technology Hefei 230601China Helmholtz Institute Mainz Staudinger Weg 18D-55099 MainzGermany Henan Normal University Xinxiang 453007China Henan University Kaifeng 475004China High Energy Physics Center Chung-Ang UniversitySeoul 06974Korea Higher School of Economy 11 Pokrovsky Bulvar Moscow 109028Russia Huangshan University Huangshan 245000China Hubei University of Automotive Technology Shiyan 442002China Hunan Normal University Changsha 410081China Hunan University of Science and Technology Xiangtan 411201China Hunan University Changsha 410082China Indiana University BloomingtonIndiana 47405USA Inner Mongolia University Hohhot 010021China Institute of Advanced Science Facilities Shenzhen 518107China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Institute of Physics Academia SinicaTaipeiTaiwan 11529China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190China jilin University Changch

The superτ-charm facility(STCF)is an electron–positron collider proposed by the Chinese particle physics *** is designed to operate in a center-of-mass energy range from 2 to 7 GeV with a peak luminosity of 0.5×10^(35) cm^(–2)·s^(–1) or *** STCF will produce a data sample about a factor of 100 larger than that of the presentτ-charm factory—the BEPCII,providing a unique platform for exploring the asymmetry of matter-antimatter(charge-parity violation),in-depth studies of the internal structure of hadrons and the nature of non-perturbative strong interactions,as well as searching for exotic hadrons and physics beyond the Standard *** STCF project in China is under development with an extensive R&D *** document presents the physics opportunities at the STCF,describes conceptual designs of the STCF detector system,and discusses future plans for detector R&D and physics case studies.

关键词： electron–positron collider tau-charm region high luminosity STCF detector conceptual design

Universal insertion of molecules in ionic compounds under pressure

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National Science Review 2024年第1期11卷 120-128页

作者： Feng Peng yanming Ma Chris j.Pickard Hanyu liu Maosheng Miao College of Physics and Electronic Information Luoyang Normal University Department of Chemistry and Biochemistry California State University Northridge State Key Laboratory of Superhard Materials & Key Laboratory of Material Simulation Methods and Software of Ministry of Education College of Physics Jilin University International Center of Future Science Jilin University Department of Materials Science & Metallurgy University of Cambridge Advanced Institute for Materials Research Tohoku University Department of Earth Science University of California Santa Barbara

Using first-principles calculations and crystal structure search methods, we found that many covalently bonded molecules such as H2, N2, CO2, NH3, H2O and CH4may react with NaC l, a prototype ionic solid,and form stable compounds under pressure while retaining their molecular structure. These molecules,despite whether they are homonuclear or heteronuclear, polar or non-polar, small or large, do not show strong chemical interactions with surrounding Na and Cl ions. In contrast, the most stable molecule among all examples, N2, is found to transform into cyclo-N5-anions while reacting with NaC l under high pressures. It provides a new route to synthesize pentazolates, which are promising green energy materials with high energy density. Our work demonstrates a unique and universal hybridization propensity of covalently bonded molecules and solid compounds under pressure. This surprising miscibility suggests possible mixing regions between the molecular and rock layers in the interiors of large planets.

关键词： molecule-solid hybrid materials high-pressure crystal structure prediction density functional theory planet interior