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Science China Mathematics 2024年第4期67卷 919-950页

作者： Xiaoqing Chi hui Zhang Xiaoyun Jiang School of Mathematics and Statistics Shandong UniversityWeihai 264209China School of Mathematics Shandong UniversityJinan 250100China

In this paper,w. first establish a new.fractional magnetohydrodynamic(MHD)coupled flow.and heat transfer model for a generalized second-grade *** coupled model consists of a fractional momentum equation and a heat conduction equation w.th a generalized form of Fourier *** second-order fractional backw.rd difference formula is applied to the temporal discretization and the Legendre spectral method is used for the spatial *** fully discrete scheme is proved to be stable and convergent w.th an accuracy of O(τ^(2)+N-r),w.ereτis the time step-size and N is the polynomial *** reduce the memory requirements and computational cost,a fast method is developed,w.ich is based on a globally uniform approximation of the trapezoidal rule for integrals on the real *** strict convergence of the numerical scheme w.th this fast method is *** present the results of several numerical experiments to verify the effectiveness of the proposed ***,w. simulate the unsteady fractional MHD flow.and heat transfer of the generalized second-grade fluid through a porous *** effects of the relevant parameters on the velocity and temperature are presented and analyzed in detail.

关键词： fractional MHD coupled flow.and heat transfer model generalized second-grade fuid fast method convergence analysis numerical simulation

Berry-Esseen bounds and moderate deviations for the norm, entries and spectral radius of products of positive random matrices

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Science China Mathematics 2024年第3期67卷 627-646页

作者： hui Xiao Ion Grama Quansheng Liu Institut fur Mathematik und Angew.ndte Informatik Universitat HildesheimHildesheim 31141Germany Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China LMBA Universite Bretagne SudCNRS UMR 6205Vannes F-56000France

Let(g_(n))_(n≥1) be a sequence of independent and identically distributed positive random d×d matrices and consider the matrix product G_(n)=g_(n)…g_*** suitable conditions,w. establish the Berry-Esseen bounds on the rate of convergence in the central limit theorem and Cramer-type moderate deviation expansions,for any matrix norm ‖G_(n)‖ of G_(n),its entries G_(n)^(i,j) and its spectral radius ρ(G_(n)).Extended versions of their joint law.w.th the direction of the random w.lk G_(n)x are also established,w.ere x is a starting point in the unit sphere of R~d.

关键词： Berry-Esseen bound Cramér-type moderate deviation product of random matrices operator norm entry spectral radius

Regio-and Stereoselective Polymerization of Bio-based Ocimene by Rare-Earth Metal Catalysts

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Chinese Journal of Polymer Science 2024年第2期42卷 223-229,I0008页

作者： Qi-Yuan w.ng Li-Peng Sang Zhen Zhang Yang Jiang hui Tian Xia Zhao Xiang Guo Shi-hui Li State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei230026China Science and Technology on Aerospace Chemical Pow.r Laboratory Hubei Institute of Aerospace ChemotechonologyXiangyang441003China Shanxi Coal Chemical Industry Technology Research Institute Xi’an710000China Hubei Institute of Aerospace Chemotechonology Xiangyang441003China

Coordination polymerization of renew.ble β-ocimene has been investigated using asymmetric diiminophosphinate lutetium complex1, β-diketiminate yttrium complex 2, bis(phosphino)carbazolide yttrium complex 3, half-sandw.ch benzyl fluorenyl scandium complex 4 and pyridyl-methylene-fluorenyl rare-metal complexes 5a–5c. Complexes 1, 4 and 5a–5c show.trans-1,2-regioselectivities and high activities, of w.ich 5c exhibits excellent isoselectivity(mmmm>99%). Conversely, complexes 2 and 3 promote β-ocimene polymerization to produce isotactic cis-1,4-polyocimenes(cis-1,4>99%, mm>95%). Diblock copolymers cis-1,4-PIP-block-cis-1,4-POc and cis-1,4-PBD-block-cis-1,4-POc are obtained in one-pot reactions of β-ocimene w.th isoprene and butadiene using complex 3. Epoxidation and hydroxylation of polyocimene afford functionalized polyolefins w.th enhanced T_(g)(from-20 ℃ to 79 ℃ and 74 ℃) and hydrophilicity.

关键词： Biobased monomer Terpenes Ocimene Rare-earths Polymerization Regio/stereoselectivity Elastomer

On hypersurfaces of H2×H2

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Science China Mathematics 2024年第2期67卷 339-366页

作者： Dong Gao hui Ma Zeke Yao School of Science Beijing University of Civil Engineering and Architecture Department of Mathematical Sciences Tsinghua University

In this paper, w. study hypersurfaces of H2× H2. w. first classify the hypersurfaces w.th constant principal curvatures and constant product angle functions. Then w. classify homogeneous hypersurfaces and isoparametric hypersurfaces, respectively. Finally, w. classify the hypersurfaces w.th at most tw. distinct constant principal curvatures, as w.ll as those w.th three distinct constant principal curvatures under some additional conditions.

关键词： constant principal curvature homogeneous hypersurface isoparametric hypersurface 53C42 53B25 53C40

Complex interactions among insect viruses-insect vector-arboviruses

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Insect Science 2024年第3期31卷 683-693页

作者： hui w.ng Qian Chen Taiyun w.i State Key Laboratory of Ecological Pest Control for Fujian and Taiw.n Crops Vector-borne Virus Research CenterFujian Agriculture and ForestryUniversityFuzhouChina

Insects are the host or vector of diverse viruses including those that infect vertebrates,plants,and *** viruses reside inside their insect hosts and are vertically transmitted from parent to *** insect virus-host relationship is intricate,as these viruses can impact various aspects of insect biology,such as development,reproduction,sex ratios,and ***-borne viruses(arboviruses)that cause substantial global health or agricultural problems can also be vertically transmitted to insect vector *** infections w.th insect viruses and arboviruses are common in *** coinfections involve complex interactions,including synergism,dependence,and *** studies have shed light on the influence of insect viruses on the competence of insect vectors for *** this review.w. focus on the biological effects of insect viruses on the transmission of arboviruses by *** also discuss the potential mechanisms by w.ich insect viruses affect the ability of hosts to transmit arboviruses,as w.ll as potential strategies for disease control through manipulation of insect *** of the interactions among insect vectors,insect viruses and arboviruses w.ll provide new.opportunities for development of innovative strategies to control arbovirus transmission.

关键词： arbovirus insect biology insect vectors insect virus interaction transmission

Adhesion Performances Betw.en Tw. Orthotropic Solids Influenced by Temperature Increment

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Acta Mechanica Solida Sinica 2024年第3期37卷 430-443页

作者： Qing-hui Luo Yue-Ting Zhou School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai200092China

The classical adhesive contact models belong to isothermal adhesion theories,w.ere the effect of temperature on adhesion w.s ***,a number of experimental results indicated that the adhesion behaviors can be significantly affected by *** this paper,the tw.-dimensional non-slipping anisothermal adhesion behaviors betw.en tw. orthotropic elastic cylinders are investigated w.thin the framew.rk of the Johnson-Kendall-Roberts *** stated problem is reduced to the coupled singular integral equations by virtue of the Fourier integral transform,w.ich are solved analytically w.th the analytical function *** closed-form solutions for the stress fields in the presence of thermoelastic effect are *** stable equilibrium state of contact system is determined by virtue of the Griffith energy *** effect of temperature difference on adhesion behaviors betw.en orthotropic solids is *** is found that the difference betw.en the oscillatory and non-oscillatory solutions increases w.th increasing the degree of anisotropy of orthotropic *** oscillatory solution cannot be w.ll approximated by the non-oscillatory solution for the orthotropic materials w.th relatively high anisotropy.

关键词： Adhesive contact Non-slipping JKR model Temperature Griffith energy balance

Advancing cell-based therapy in sepsis:An anesthesia outlook

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Chinese Medical Journal 2024年第13期137卷 1522-1534页

作者： hui Ye Xiaoyu Zou Xiangming Fang Department of Anesthesiology and Intensive Care The First Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310003China The Children’s Hospital National Clinical Research Center for Child HealthSchool of MedicineZhejiang UniversityHangzhouZhejiang 312000China

Sepsis poses a health challenge globally ow.ng to markedly high rates of morbidity and *** employing bundle therapy over tw. decades,approaches including transient organ supportive therapy and clinical trials focusing on signaling pathw.ys have failed in effectively reversing multiple organ failure in patients w.th *** and appropriate perioperative management for surgical patients w.th concurrent sepsis is ***,innovative therapies focusing on remedying organ injuries are *** therapy has emerged as a promising therapeutic avenue for repairing local damage to vital organs and restoring homeostasis during perioperative treatment for *** the pivotal role of immune cell responses in the pathogenesis of sepsis,stem cell-based interventions that primarily modulate immune responses by interacting w.th multiple immune cells have progressed into clinical *** strides made in single-cell sequencing and gene-editing technologies have advanced the understanding of disease-specific immune responses in *** antigen receptor(CAR)-immune cell therapy offers an intriguing option for the treatment of *** review.provides a concise overview.of immune cell therapy,its current status,and the strides made in the context of sepsis research,discussing potential strategies for the management of patients w.th sepsis during perioperative stages.

关键词： Sepsis Perioperative Receptors,chimeric antigen Immunotherapy,adoptive Perfusion Tissue repair Multiple organ failure Shock,septic

w.yl Type Theorem for Bounded Linear Operator and Its Functional Calculus

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Acta Mathematica Sinica,English Series 2024年第2期40卷 528-536页

作者： Gao hui Zi FENG Peng Tong LI School of Mathematics Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

Let H be a complex infinite dimensional Hilbert space and B(H)be the algebra of all bounded linear operators on *** this paper,w. mainly study the operators that satisfy both a-w.yl's theorem and property(R).Also,the operators w.ose functional calculus satisfies the tw. properties are also *** give the features for the operator or its functional calculus for w.ich both a-w.yl's theorem and property(R)hold.

关键词： a-w.yl's theorem property(R) functional calculus

Preventing formation of intermetallic compounds in ultrasonic-assisted Sn soldering of Mg/Al alloys through pre-plating a Ni coating layer on the Mg substrate

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Journal of Magnesium and Alloys 2024年第2期12卷 726-741页

作者： Yingzong Liu Yuanxing Li hui Chen Zongtao Zhu Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031PR China

Magnesium and aluminum alloys are w.dely used in various industries because of their excellent properties,and their reliable connection may increase application of *** compounds(IMCs)affect the joint performance of Mg/*** this study,AZ31 Mg alloy w.th/w.thout a nickel(Ni)coating layer and 6061 Al alloy w.re joined by ultrasonic-assisted soldering w.th Sn-3.0Ag-0.5Cu(SAC)*** effects of the Ni coating layer on the microstructure and mechanical properties of Mg/Al joints w.re systematically *** Ni coating layer had a significant effect on formation of the Mg_(2)Sn IMC and the mechanical properties of Mg/Al *** blocky Mg_(2)Sn IMC formed in the Mg/SAC/Al joints w.thout a Ni coating *** content of the Mg_(2)Sn IMC increased w.th increasing soldering temperature,but the joint strength *** joint w.thout a Ni coating layer fractured at the blocky Mg_(2)Sn IMC in the solder,and the maximum shear strength w.s 32.2 *** pre-plating Ni on the Mg substrate,formation of the blocky Mg_(2)Sn IMC w.s inhibited in the soldering temperature range 240–280℃and the joint strength ***,w.en the soldering temperature increased to 310℃,the blocky Mg_(2)Sn IMC precipitated again in the *** electron microscopy show.d that some nano-sized Mg_(2)Sn IMC and the(Cu,Ni)_(6)Sn_(5)phase formed in the Mg(Ni)/SAC/Al joint soldered at 280℃,indicating that the Ni coating layer could no longer prevent diffusion of Mg into the solder w.en the soldering temperature w.s higher than 280℃.The maximum shear strength of the Mg(Ni)/SAC/Al joint w.s 58.2 MPa for a soldering temperature of 280℃,w.ich w.s 80.7%higher than that of the Mg/SAC/Al joint,and the joint w.s broken at the Mg(Ni)/SAC ***-plating Ni is a feasible w.y to inhibit formation of IMCs w.en joining dissimilar metals.

关键词： Ultrasonic-assisted soldering Mg_(2)Sn Ni coating layer Shear strength

Local Hamilton type Gradient Estimates and Harnack Inequalities for Nonlinear Parabolic Equations on Riemannian Manifolds

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 539-546页

作者： w.n w.NG Da-peng XIE hui ZHOU School of Mathematics and Statistics Hefei Normal UniversityHefei 230601China

In this paper,w. prove a local Hamilton type gradient estimate for positive solution of the nonlinear parabolic equation ut(x,t)=Δu(x,t)+au(x,t) ln u(x,t)+bu^(α)(x,t),on M×(-∞,∞) w.th α∈R,w.ere a and b are *** ... 详细信息

关键词： nonlinear parabolic equation gradient estimate Harnack inequality