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Global Solvability,Pattern Formation and Stability to a Chemotaxis-haptotaxis Model with Porous Medium Diffusion

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Acta Mathematica Sinica,English Series 2023年第8期39卷 1597-1623页

作者： Chun hua jin School of Mathematical Sciences South China Normal UniversityGuangzhou 510631P.R.China

In this paper,we deal with the following chemotaxis-haptotaxis system modeling cancer invasion with nonlinear diffusion,ut=Δum−χ∇·(u∇v)−ξ∇·(u∇ω)+μu(1−u−ω),inΩ×R^(+),vt−Δv+v=u,inΩ×R+,ωt=−vω,inΩ×R+,whereΩ⊂R^(N)is a bounded *** first supplement the results of global existence and uniform boundedness of solutions for the case m=2N N+*** for any m>0 and any spatial dimension,we consider the stability of equilibrium,and find that the chemotaxis has a destabilizing effect,that is for the ODEs,or the diffusion-ODE system without chemotaxis,the solutions tend to a linearly stable uniform steady state(1,1,0).When the chemotactic coefficientχis large,the equilibrium(1,1,0)become *** we study the existence of nontrivial stationary solutions via bifurcation techniques withχbeing the bifurcation parameter,and obtain nonhomogeneous *** last,we also investigate the stability of these bifurcation solutions.

关键词： Chemotaxis-haptotaxis porous medium diffusion pattern formation stability

Neottia wuyishanensis(Orchidaceae:Neottieae),a new species from Fujian,China

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Plant Diversity 2021年第5期43卷 426-431页

作者： Bing-hua Chen Xiao-hua jin College of Life Sciences Fujian Normal UniversityFuzhou 350117China State Key Laboratory of Systematic and Evolutionary Botany and Herbarium Institute of BotanyChinese Academy of SciencesBeijing 100093China The Public Service Platform for Industrialization Development Technology of Marine Biological Medicine and Products of the State Oceanic Administration Fujian Key Laboratory of Special Marine Bioresource Sustainable UtilizationSouthern Institute of OceanographyCollege of Life SciencesFujian Normal UniversityFuzhou 350117China

A new species,Neottia wuyishanensis(Neottieae,Orchidaceae),is described and illustrated from Wuyishan,Fujian,eastern China,based on morphological characters and molecular *** phylogenetics indicate that *** is nested within the clade formed by Neottia fugongensis and Neottia ***,*** is similar to *** and ***,but differs from them by having indistinct auricles at the base,and in the shape and size of lobelets.

关键词： China Neottia wuyishanensis New species Orchidaceae

Preparation and Tribological Properties of Ni-P Electroless Composite Coating Containing Potassium Titanate Whisker

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Journal of Materials Science & Technology 2007年第3期23卷 387-391页

作者： Yaxu jin Lin hua School of Materials Science and Engineering Wuhan University of Technology Wuhan 430070 China

Nickel-phosphorus （Ni-P） composite coatings containing potassium titanate （K2Ti6O13） whiskers （PTWs） were prepared by electroless plating. The surface morphology and component of coatings were investigated by scanning electron microscopy （SEM） and energy dispersive X-ray spectroscopy （EDX）, respectively before and after wear test. The tribological performance was evaluated using a pin-on-disk wear tester under dry conditions. It is found that the Ni-P-PTWs composite coatings exhibit higher wear resistance than Ni-P and Ni-P-SiC electroless coatings. The favorable effects of PTWs on the tribological properties of the composite coatings are attributed to the super-strong mechanical properties and the specific tunneling structures of PTWs. The PTWs greatly reinforce the structure of the Ni-P-based composite coatings and thereby greatly reduce the adhesive and plough wear of Ni-P-PTWs composite coatings.

关键词： Potassium titanate whiskers Electroless plating Composite coating Tribological properties

Kantorovich’s theorem for Newton’s method on Lie groups

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 978-986页

作者： WANG jin-hua LI Chong Department of Mathematics Zhejiang University of Technology Hangzhou 310032 China Department of Mathematics Zhejiang University Hangzhou 310027 China

The convergence criterion of Newton’s method to find the zeros of a map f from a Lie group to its corresponding Lie algebra is established under the assumption that f satisfies the classical Lipschitz condition, and that the radius of convergence ball is also obtained. Furthermore, the radii of the uniqueness balls of the zeros of f are estimated. Owren and Welfert (2000) stated that if the initial point is close sufficiently to a zero of f, then Newton’s method on Lie group converges to the zero; while this paper provides a Kantorovich’s criterion for the convergence of Newton’s method, not requiring the existence of a zero as a priori.

关键词： Newton's method Lie group Kantorovich's theorem Lipschitz condition

Analysis of φ-divergence for Loglinear Models with Constraints under Product-multinomial Sampling

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 93-104页

作者： Ying-hua jin Yao-hua Wu Department of Statistics and Finance University of Science and Technology of China Faculty of Applied Mathematics Guangdong University of Technology

The loglinear model under product-multinomial sampling with constraints is considered. The asymptotic expansion and normality of the restricted minimum C-divergence estimator （RMDE） which is a generalization of the maximum likelihood estimator is presented. Then various statistics based on C-divergence and RMCDE are used to test various hypothesis test problems under the model considered. These statistics contain the classical loglikelihood ratio test statistics and Pearson chi-squared test statistics. Ia the last section, a simulation study is implemented.

关键词： loglinear model product-multinomial sampling Restricted minimum C-divergence estimator(RMDE) C-divergence test statistics

Effect of Growth Temperature on Carbon Nanotube Grafting Morphology and Mechanical Behavior of Carbon Fibers and Carbon] Carbon Composites

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Journal of Materials Science & Technology 2017年第1期33卷 65-70页

作者： Lei Feng Ke-Zhi Li jin-hua Lu Le-hua Qi State Key Laboratory of Solidification Processing Carbon/Carbon Composites Research Center Northwestern Polytechnical University Xi'an 710072 China School of Mechatronic Engineering Northwestern Polytechnical University Xi'an 710072 China

High-purity carbon nanotubes （CNTs） with different orientation and lengths were grafted on carbon fibers （CFs） in woven fabrics by using double injection chemical vapor deposition and adjusting the growth temperature. Scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and Raman investigations reveal that the grafted CNTs change from being predominantly aligned and uniform in di- ameter to absolutely disordered and variable in diameter, whilst they show significantly increased crystallinity, as the growth temperature is increased from 730 ~C to 870 ~C. In tensile tests of fiber bundles, much more strength degradation of CFs was observed after the growth process at higher temperature than that at lower temperature. These hybrid preforms produced at different growth temperatures were used to reinforce carbon/carbon （C/C） composites. An increment of 34.4% in out-of-plane compressive strength （OCS） was obtained for the composites containing CNTs grown at 730℃, while the OCS increment exhibits an obvious decrease with increasing the growth temperature. Compared with the higher growth temperature, the lower temperature contributes to the decrease in the strength loss of reinforcing fibers and meanwhile the growth of large extending length of CNTs, which can provide long reinforcement to the pyrocarbon matrix, and thus increase the compressive strength better.

关键词： Carbon nanotubes Carbon fibers Chemical vapor deposition Carbon/carbon composites Mechanical strength

Strengthening mechanisms of reduced activation ferritic/martensitic steels:A review

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International Journal of Minerals,Metallurgy and Materials 2021年第3期28卷 335-348页

作者： jin-hua Zhou Yong-feng Shen Nan Jia Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China The State Key Lab of Rolling&Automation Northeastern UniversityShenyang 110819China

This review summarizes the strengthening mechanisms of reduced activation ferritic/martensitic(RAFM)***-angle grain boundaries,subgrain boundaries,nano-sized M_(23)C_(6),and MX carbide precipitates effectively hinder dislocation motion and increase high-temperature strength.M23C6 carbides are easily coarsened under high temperatures,thereby weakening their ability to block *** properties are improved through the reduction of M23C6 ***,the loss of strength must be compensated by other strengthening *** review also outlines the recent progress in the development of RAFM *** dispersion-strengthened steels prevent M23C6 precipitation by reducing C content to increase creep life and introduce a high density of nano-sized oxide precipitates to offset the reduced *** plastic deformation methods can substantially refine subgrains and MX carbides in the *** thermal deformation strengthening of RAFM steels mainly relies on thermo-mechanical treatment to increase the MX carbide and subgrain *** procedure increases the creep life of TMT(thermo-mechanical treatment)9Cr-1W-0.06Ta steel by~20 times compared with those of F82H and Eurofer 97 steels under 550℃/260 MPa.

关键词： reduced activation ferritic/martensitic steel strengthening mechanism high-angle grain boundary subgrain boundary precipitate

A novel heterogeneous Co(Ⅱ)-Fenton-like catalyst for efficient photodegradation by visible light over extended pH

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Science China Chemistry 2020年第12期63卷 1825-1836页

作者： Wu-hua Chen jin-hua Xiong Xue Teng jin-Xiao Mi Zhi-Biao Hu Haifeng Wang Zuofeng Chen Fujian Provincial Colleges and University Engineering Research Center of Solid Waste Resource Utilization(Longyan University) College of Chemistry and Material ScienceLongyan UniversityLongyan 364012China Shanghai Key Laboratory of Chemical Assessment and Sustainability School of Chemical Science and EngineeringTongji UniversityShanghai 200092China Key Laboratory for Advanced Materials Centre for Computational Chemistry and Research Institute of Industrial CatalysisEast China University of Science and TechnologyShanghai 200237China Department of Materials Science and Engineering College of MaterialsXiamen UniversityXiamen 361005China

A novel Co^Ⅱ-Fenton-like heterogeneous catalyst,(H3O)2[Co^Ⅱ(phen)(H2O)2]2[Mo^Ⅵ5O15(PO4)2]·4H2O (phen=1,10-phenanthroline,C12N2H8)(1),is synthesized and utilized for photocatalytic degradation of organic dyes and antibiotic in a wide range of *** experimental results show that 1 acting as the Fenton-like catalyst with H2O2 exhibits remarkable activity at pH 3–9 under vis-light irradiation and is merited with excellent recyclability and reusability.A variety of analytical methods,including in-situ electron paramagnetic resonance (EPR) spectroscopy and density functional theory (DFT) calculations,are applied to study the mechanism on generation of·OH and O2^·-radicals for photocatalytic *** suggests that,unlike the classical Fenton process involving the redox transformation of the central cations,the generation of·OH and O2^·-radicals is associated with the substitution of the coordinating water molecules at Co(Ⅱ) by H2O2 and/or OOH^-,followed by the light-driven O–O bond cleavage and *** outcomes of this study are striking which overcome the obstacles in the classical Fe^Ⅱ-Fenton process,including the slow redox transformation between Fe(Ⅱ) and Fe(Ⅲ) and the production of massive iron precipitates especially at elevated *** opens up new avenues for the development of the high-performance Fenton(-like) catalysts for photocatalytic degradation over extended pH and provides new insight into the related process.

关键词： Co^Ⅱ-Fenton-like reagent polyoxometalate photocatalytic degradation density functional theory(DFT)calculations in-situ EPR spectroscopic analysis

Novel Localized Excitations of Nonlinear Coupled Scalar Fields

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Communications in Theoretical Physics 2008年第6期49卷 1365-1372页

作者： LI jin-hua WU huang-Jiao Department of Physics and Center of Nonlinear Science Ningbo University Ningbo 315211 China

Some extended solution mapping relations of the nonlinear coupled scalar field and the well-known φ^4 model are presented. Simultaneously, inspired by the new solutions of the famous φ^4 model recently proposed by Jia, huang and Lou, five kinds of new localized excitations of the nonlinear coupled scaiar field （NCSF） system are obtained.

关键词： nonlinear coupled scalar field solitary wave structure mapping and deformation approach