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Microstructural evolution and mechanical properties of 55NiCrMoV7 hot-work die steel during quenching and tempering treatments

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Advances in Manufacturing 2021年第4期9卷 520-537页

作者： Xing-Sheng Yu Chuan Wu Ru-Xing Shi ya-sha Yuan Luoyang CITIC HIC Casting&Forging Co. LtdLuoyang 471039HenanPeople’s Republic of China National-Local Joint Engineering Laboratory of Intelligent Manufacturing Oriented Automobile Die&Mould Tianjin University of Technology and EducationTianjin 300222People’s Republic of China CITIC Heavy Industries Co. LtdLuoyang 471039HenanPeople’s Republic of China

55NiCrMoV7 hot-work die steel is mainly used to manufacture heavy forgings in the fields of aerospace and *** study aims to clarify the effects of heat treatment on the microstructural evolution and mechanical properties of the steel,in order to find out an optimal heat treatment scheme to obtain an excellent balance of strength,ductility and *** steel was quenched at temperature from 790℃ to 910℃ followed by tempering treatments of 100–650℃ for 5 *** mechanical property tests were carried out by tensile,impact toughness and *** microscope(OM),scanning electron microscope(SEM)and transmission electron microscope(TEM)were used to observe the austenite grains,lath martensite,carbides and fracture *** results show that the quenching temperature mainly influences the austenite grain size and the volume fraction of undissolved carbides(UCs),while the tempering temperature mainly influences the size and morphology of the martensite with a body centered cubic(BCC)and the carbides with a face centered cubic(FCC).The mechanical properties of the steel,including yield and tensile strength,ductility,impact toughness and hardness,get an excellent balance at a quenching range of 850–870*** the tempering temperature increases,the yield and tensile strength and hardness decrease,while the ductility and impact toughness *** variation trends can be further verified by fracture SEM observation and *** with a macro-micro coupled finite element(MMFE)modeling technique,the cooling rate,microstructural evolution and yield strength of the steel were predicted and compared with the tested data.

关键词： Hot-work die steel Microstructural evolution Mechanical properties Heat treatment Macro-micro coupled modeling and simulation

Revised Geometric Measure of Entanglement for Multipartite and Continuous Variable Systems

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Communications in Theoretical Physics 2009年第4期51卷 613-620页

作者： CAO ya WANG An-min Department of Physics Xuzhou Normal University Xuzhou 221116 China Department of Modern Physics University of Science and Technology of China Hefei 230026 China

Based on the revised geometric measure of entanglement （RGME） proposed by us [J. Phys. A： Math. Theor. 40 （2007） 3507], we obtain the RGME of multipartite state including three-qubit GHZ state, W state, and the generalized Smolin state （GSS） in the presence of noise and the two-mode squeezed thermal state. Moreover, we compare their RGME with geometric measure of entanglement （GME） and relative entropy of entanglement （RE）. The results indicate RGME is an appropriate measure of entanglement. Finally, we define the Gaussian GME which is an entangled monotone.

关键词： quantum entanglement symmetric state revised geometric measure of entanglement relative entropy of entanglement

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： ya-Ping shao Zhuo-min Chi Yong-min Liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking

Experimental study of anti-cavitation mechanism of valve lintel natural aeration of high head lock

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Journal of Hydrodynamics 2020年第2期32卷 337-344页

作者： Xin Wang ya-an Hu Jian-min Zhang Hydraulic Engineering Department Nanjing Hydraulic Research InstituteNanjing210029China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing210029China

To study the serious valve top gap cavitation of Datengxia high head single-lift ship lock,the 1:1 scale slice experiment is carried out,to truly reveal the gap flow characteristics,as well as the valve top gap cavitation characteristics and the anti-cavitation mechanism of natural *** kinds of cavitation,namely,the throat cavitation,the mainstream inner cavitation,and the valve plate cavitation,are determined and they are found to occur step-by-step in the gap section in the development of the *** to the anti-cavitation mechanism of the natural aeration,the pressure of the gap flow through the ventilation is increased,to avoid the mainstream inner cavitation and the valve plate cavitation,and to weaken the throat *** negative pressure zone in the gap section gradually extends with the development of the cavitation until the gap section is filled with a stable−10 m water *** the natural aeration measure is employed,the pressure in the gap section approximately reaches the−2 m water head,and the cavitation *** systematic tests reveal the quadratic polynomial relationship between the pressure in the gap and the ventilation per meter *** pressure,which corresponds to the maximum value of the ventilation at the beginning of the gap,approximately reaches the−2 m water head,and the pressure and the ventilation reach the equilibrium state *** the pressure in the gap increases when the valve is opened,the ventilation gradually decreases until the natural aeration *** gap section length for the high head valves has a great effect on the natural aeration and should be long enough to maintain the stable negative pressure in the gap,whereas the throat width has a minimal *** can be used for the anti-cavitation design of the high head lock valve.

关键词： High head lock valve top gap cavitation natural aeration slice experiment

CUSTOMS REGULATIONS OF THEPEOPLE'S REPUBLIC OF CHINA CONCERNING THE CONTROL OVER DECLARANTS

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大经贸 1997年第5期 87-89页

作者： yang ya sha

Chapter Ⅰ General Provisions Article 1 This set of regulations has been formulated in accordancewith the Customs Laws of the People’s Republic of China andOther Related laws and regulations for the purpose of strengthening the control over declarants, preserving the order of customs clearanceand standardizing the customs clearance. Article 2 the term "declarants" as used in these Regulations refers tosuch personnel who have obtained the qualifications of a declarant andregistered with the customs according to the procedures as provided inthese Regulations, and shall declare at the customs import and exportgoods. Article 3 The customs of the People’s Republic of China shall be thecompetent institution responsible for the qualification examinations, registration of declarants and supervision and control over the performanceof declarants. Article 4 Delarants shall abide by the relevant national laws rulesand regulations as well as the relevant customs regulations, declare

关键词：入门

The Global Well-posedness of Strong Solutions to 2D MHD Equations in Lei-Lin Space

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Acta Mathematicae Applicatae Sinica 2023年第3期39卷 647-655页

作者： Bao-quan YUAN ya-min XIAO School of Mathematics and Information Science Henan Polytechnic UniversityJiaozuo 454000China

In this paper, we study the Cauchy problem of the 2D incompressible magnetohydrodynamic equations in Lei-Lin space. The global well-posedness of a strong solution in the Lei-Lin space χ^(-1)(R^(2)) with any initial data in χ^(-1)(R^(2)) ∩ L^(2)(R^(2)) is established. Furthermore, the uniqueness of the strong solution in χ^(-1)(R^(2)) and the Leray-Hopf weak solution in L^(2)(R^(2)) is proved.

关键词： 2D MHD equations strong solutions Lei-Lin space weak-strong uniqueness

Anterior segment OCT application in quantifying posterior capsule opacification severity with varied intraocular lens designs

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International Journal of Ophthalmology(English edition) 2021年第9期14卷 1384-1391页

作者： sha-sha Yu Cheng-Zhe Lu ya-Wen Guo Yun Zhao Xiao-Yong Yuan Tianjin Eye Hospital Tianjin Key Lab of Ophthalmology and Visual ScienceTianjin Eye InstituteClinical College of OphthalmologyTianjin Medical UniversityNankai University Eye HospitalTianjin 300020China

AIM:To evaluate the application of anterior segmentoptical coherence tomography(AS-OCT)in posterior capsule opacification(PCO)severity assessment and analyse the relationship between PCO severity and intraocular lens(IOL)***:PCO patients were prospectively ***-sectional images of the anterior segment at horizontal and vertical meridians were acquired with *** area of the IOL-PC(posterior capsular)space and PCO severity(area,thickness,and density at 3 mm and 5 mm IOL optic regions)were *** relationship between PCO severity and visual acuity,comparisons of PCO severity and IOL-PC space using varied IOL designs were ***:One hundred PCO eyes were ***-PC space,PCO thickness and area were positively correlated with axial *** addition,PCO area and thickness were positively correlated with visual acuity when it was≤0.52 log *** cut-off level of visual acuity should be 0.52 log *** varied IOL designs,3-piece C haptic IOL showed a smaller PCO area and thickness than the 1-piece 3 haptic IOL and 1-piece 4 haptic *** area and thickness values for an IOL with a diameter≤11.0 mm was greater than for an IOL with a diameter of 12.5 mm,and the differences were statistically *** area and thickness increased when IOL haptic angulation increased(from 0 to 12 degrees).CONCLUSION:In PCO eyes,cut-off level of visual acuity is 0.52 log *** more severe PCO,visual acuity maybenot enough to describe the visual function *** severity and IOL-PC space are significantly correlated with axial length and IOL design and material.

关键词： posterior capsule opacification anterior segment-optical coherence tomography IOL-posterior capsule space IOL-posterior capsule distance severity

Detection of electron-phonon coupling in two-dimensional materials by light scattering

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Nano Research 2021年第6期14卷 1711-1733页

作者： Jia-min Lai ya-Ru Xie Jun Zhang State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China CAS Center of Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing101408China Beijing Academy of Quantum Information Science Beijing100193China

Electron-phonon coupling affects the properties of two-dimensional(2D)materials significantly,leading to a series of novel *** light scattering provides a powerful experimental tool to explore electron-phonon interaction in 2D *** review gives an overview of the basic theory and experimental advances of electron-phonon coupling in 2D materials detected by Raman and Brillouin scattering,*** the Raman scattering part,we review Raman spectroscopy studies of electron-phonon coupling in graphene,transition metal disulfide compounds,van der Waals heterostructures,strongly correlated systems,and 2D magnetic *** the Brillouin scattering part,we extensively introduce Brillouin spectroscopy in non-van der Waals 2D structures,including temperature sensors for phonons and magnons,interfacial Dzyaloshinsky-Moriya.interaction and spin torque in multilayer magnetic structures,as well as exciton-polariton in semiconductor quantum well.

关键词： electron-phonon coupling Raman scattering Brillouin scattering two-dimensional(2D)materials

LU Invariants and Canonical Forms and SLOCC Classification of Pure 3-Qubit States

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Communications in Theoretical Physics 2006年第4期45卷 596-600页

作者： DI yao-min Cao ya Department of Physics Xuzhou Normal University Xuzhou 221116 China

In this paper the entanglement of pure 3-qubit states is discussed. The local unitary （LU） polynomial invariants that are closely related to the canonical forms are constructed and the relations of the coefficients of the canonical forms are given. Then the stochastic local operations and classlcal communication （SLOCC） classification of the states are discussed on the basis of the canonical forms, and the symmetric canonical form of the states without 3-tangle is discussed. Finally, we give the relation between the LU polynomial invariants and SLOCC classification.

关键词： 3-qubit state canonical form LU invariant SLOCC classification