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Cast-rolling force model of multi-roll solid–liquid cast-rolling bonding process for fabricating metal cladding materials

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Chinese Journal of Aeronautics 2023年第9期36卷 346-368页

作者： Ce ji Huagui HUANG College of Mechanical and Vehicle Engineering Taiyuan University of TechnologyTaiyuan 030024China Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment of Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China National Key Laboratory of Metal Forming Technology and Heavy Equipment Taiyuan University of TechnologyTaiyuan 030024China College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao 066004China

Based on twin-roll casting technology and multi-roll groove rolling technology,a Multi-Roll Solid-Liquid Cast-Rolling Bonding(MRSLCRB)process was proposed to fabricate Cu/steel cladding bars,which processes the advantages of short flow and ***,it is a typical 3-D thermal-fluid-mechanics coupled problem,and determining cast-rolling force is difficult during the equipment ***,the geometrical evolution of the cast-rolling area was studied,laying the foundation to establish contact boundary equations and analyze mechanical schematics and metal ***,a 3-D steady-state thermal-fluid coupled simulation model,including casting roll,substrate bar,and cladding metal,was *** Kissing Point(KP)height,average outlet temperature,and process window were predicted,and simulation results of the three-roll layout indicate that the KP distribution along the circumferential direction can be considered ***,the engineering cast-rolling force model was derived based on the differential element method and plane deformation *** accuracy was verified by the 3-D finite element model,and the influences of process layouts and technological parameters on the castrolling force were *** the indirect multi-field coupled analysis method,the temperature–pressure evolution and reasonable process window can be predicted,which provides a significant basis for guiding equipment design and improving product quality.

关键词： Cast-rolling force Kissing point Multi-field coupled Numerical simulation Solid-liquid cast-rolling bonding

Application of New Empirical Models Based on Mathematical Statistics in the Through-Flow Analysis

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Journal of Thermal Science 2021年第6期30卷 2087-2098页

作者： FEI Teng ji Lucheng School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The through-flow analysis is an important part in the compressor design *** this part,lots of empirical models are used to predict the compressor aerodynamic *** models are all based on the early experimental results of low-load and low-speed compressors;so,they may not be suitable for modern compressor performance *** this study,several empirical models were reviewed,and two new models to estimate the minimum blade profile loss and minimum-loss deviation angle were established using mathematical ***,the original models with poor accuracy were replaced by these two models in through-flow ***,three compressors(Rotor 67,Stage 35,and a 4-stage repeating stage)were simulated using both the original and new *** final results show that the new models have better accuracy in estimating the performance parameters than the original *** indicates that it is feasible to use mathematical statistical methods to establish the empirical models,and this method provides an idea for the improvement of other empirical models in through-flow program.

关键词： through-flow analysis empirical models blade loss deviation regression analysis

Parton physics from large-momentum effective field theory

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Science China(Physics,Mechanics & Astronomy) 2014年第7期57卷 1407-1412页

作者： ji XiangDong INPAC Department of Physics and Astronomy Shanghai Jiao Tong University Maryland Center for Fundamental Physics Department of Physics University of Maryland College Park

Parton physics,when formulated as light-front correlations,are difficult to study non-perturbatively,despite the promise of lightfront *** an alternative approach to partons have been proposed by re-visiting original Feynman picture of a hadron moving at asymptotically large *** I formulate the approach in the language of an effective field theory for a large hadron momentum P in lattice QCD,LaMET for short.I show that using this new effective theory,parton properties,including light-front parton wave functions,can be extracted from lattice observables in a systematic expansion of 1/P,much like that the parton distributions can be extracted from the hard scattering data at momentum scales of a few GeV.

关键词： partons effective field theory lattice QCD high-energy scattering proton structure

THE ELLIPTIC TYPE NODE CONFIGURATION AND INTERPOLATION IN R^2

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Journal of Computational Mathematics 1998年第3期16卷 257-266页

作者： Ping Zhu (ji’an Teachers College, ji’an 543009, jiangxi, China) 吉安师范专科学校江西吉安 343009

In this paper, we have obtained an expression of the bivariate Vandermonde determinant for the Elliptic Type Node Configuration in R-2, and discussed the possibility of the corresponding multivariate Lagrange, Hermite... 详细信息

关键词： multivariate interpolation polynomial interpolation Birkhoff interpolation node configuration

Metric distortion in the geometric Schottky problem

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Science China Mathematics 2019年第11期62卷 2211-2228页

作者： Lizhen ji Department of Mathematics University of Michigan

The classical Schottky problem is concerned with characterization of Jacobian varieties of compact Riemann surfaces among all abelian varieties, or the identification of the Jacobian locus J(Mg) in the moduli space Ag of principally polarized abelian varieties as an algebraic subvariety. By viewing Ag as a noncompact metric space coming from its structure as a locally symmetric space and J(Mg) as a metric subspace, we compare the subspace metric d and the induced length metric ι on J(Mg). Consequently, we clarify the nature of the metric distortion of the subspace J(Mg) and hence settle a problem posed by Farb(2006) on the metric distortion of J(Mg) inside Ag in a certain sense(see Theorem 1.5 and Corollary 1.6).

关键词： metric distortion Schottky problem noncompact metric space

Probability analysis of contact forces in quasi-solid-liquid phase transition of granular shear flow

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Science China(Physics,Mechanics & Astronomy) 2013年第2期56卷 395-403页

作者： ji ShunYing State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology

The quasi-solid-liquid phase transition exists widely in different fields,and attracts more attention due to its instinctive *** structure of force chains is an important factor to describe the phase transition *** this study,the discrete element model(DEM) is adopted to simulate a simple granular shear flow with period boundary condition on micro *** quasi-solid-liquid phase transition is obtained under various volume fractions and shear *** on the DEM results,the probability distribution functions of the inter-particle contact force are obtained in different shear flow *** normal,tangential and total contact forces have the same *** distribution can be fitted as the exponential function for the liquid-like phase,and as the Weibull function for the solid-like *** describe the progressive evolution of the force distribution in phase transition,we use the Weibull function and Corwin-Ngan function,*** of them can determine the probability distributions in different phases and the Weibull function shows more reasonable ***,the force distributions are discussed to explain the characteristics of the force chain in the phase transition of granular shear *** distribution of the contact force is an indicator to determine the flow phase of granular *** the discussions on the statistical properties of the force chain,the phase transition of granular matter can be well understood.

关键词： granular materials quasi-solid-liquid phase transition force chain statistical characteristics simple shear flow

Existence of Diffusion Orbits in a Lattice System

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Acta Mathematica Sinica,English Series 2013年第6期29卷 1075-1088页

作者： ji LI Department of Mathematics Nanjing University

We study a model which is a periodic lattice system with nearest neighbors coupling. Using the variational methods, we show the existence of diffusion orbits under a generic perturbation of time periodic.

关键词： Hamiltonian system lattice system Aubry-Mather theory variational methods

Ratiometrically Designed Nanocarrier to Impact Major Cancer Pathways for Effective Pancreatic Cancer Treatment

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Chemical Research in Chinese Universities 2020年第6期36卷 1143-1144页

作者： ji jian Key Laboratory of Macromolecule Synthesis and Functionalization of Ministry of Education Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027P.R.China

To achieve secured in vivo drug synergy in stroma-rich pancreatic cancer(PDAC)is not an easy *** and Liu et *** the rational development of a ratiometrically designed nanocarrier to co-package a CDK4/6 cel cycle inhibitor palbociclib(PAL)plus an autophagy inhibitor hydroxychloroquine(HCQ)for efficient PDAC treatment The lead formulation was obtained using a computer software aided in vitro screening,followed by a remote drug co-import into a lipid-coated mesoporous silica *** ratiometric nanocarrier led to the synchronized phar-macokinetic(PK)profile and effective intratumoral buildup of the drug pair post intravenous injection,which otherwise exhibited distinctly different biodistribution *** treatment using PAL/HCQ co-delivery nanoparticle:yielded the most effective shrinkage of PDAC in subcutaneous and orthotopic PANCI mouse *** mechanistic investigation also demonstrated the activation of anti-apoptosis pathway after repetitive nanoparticle injection in mice which promoted the authors to introduce a small molecule anti-apoptosis inhibitor to further improve the performance of their already potent nanoparticle in the PDAC mouse *** work has been published online in Nature Communi cations on August 25,2020.

关键词： injection otherwise treatment

Purely tetrahedral quadruple systems

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Science China Mathematics 2006年第10期49卷 1327-1340页

作者： ji Lijun Department of Mathematics Suzhou University Suzhou 215006 China

An oriented tetrahedron is a set of four vertices and four cyclic triples with the property that any ordered pair of vertices is contained in exactly one of the cyclic triples. A tetrahedral quadruple system of order n (briefly TQS(n)) is a pair (X,B), where X is an nelement set and B is a set of oriented tetrahedra such that every cyclic triple on X is contained in a unique member of B. A TQS(n) (X, B) is pure if there do not exist two oriented tetrahedra with the same vertex set. In this paper, we show that there is a pure TQS(n) if and only if n≡2,4(mod 6),n＞4,or n≡1,5(mod 12). One corollary is that there is a simple two-fold quadruple system of order n if and only if n≡2,4 (mod 6) and n＞4, or n≡1, 5 (mod 12).Another corollary is that there is an overlarge set of pure Mendelsohn triple systems of order n for n≡1,3(mod 6),n＞3, or n≡0,4 (mod 12).

关键词： large set, t-wise balanced design, Mendelsohn triple system, quadruple system.