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Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 177-192页

作者： m.NAVEED m.ImRAN T.ASGHAR z.ABBAS Department of mathematics Division of Science and TechnologyUniversity of Education Department of mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAm).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： Peclet number

Shift current bulk photovoltaic effect in polar materials—hybrid and oxide perovskites and beyond

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npj Computational materials 2016年第1期2卷 58-69页

作者： liang z Tan Fan zheng Steve m Young Fenggong Wang Shi Liu Andrew m Rappe The makineni Theoretical Laboratories Department of ChemistryUniversity of PennsylvaniaPhiladelphiaPAUSA Center for Computational materials Science United States Naval Research LaboratoryWashingtonDCUSA Geophysical Laboratory Carnegie Institution of ScienceWashingtonDCUSA

The bulk photovoltaic effect(BPVE)refers to the generation of a steady photocurrent and above-bandgap photovoltage in a single-phase homogeneous material lacking inversion *** mechanism of BPVE is decidedly different from the typical p-n junction-based photovoltaic mechanism in heterogeneous ***,there has been renewed interest in ferroelectric materials for solar energy conversion,inspired by the discovery of above-bandgap photovoltages in ferroelectrics,the invention of low bandgap ferroelectric materials and the rapidly improving power conversion efficiency of metal halide ***,as long as the nature of the BPVE and its dependence on composition and structure remain poorly understood,materials engineering and the realisation of its true potential will be *** this review article,we survey the history,development and recent progress in understanding the mechanisms of BPVE,with a focus on the shift current mechanism,an intrinsic BPVE that is universal to all materials lacking inversion *** addition to explaining the theory of shift current,materials design opportunities and challenges will be discussed for future applications of the BPVE.

关键词： mechanism effect ferroelectric

ATOmIzATION CAUSED BY BOTTOm FLOW ENERGY DISSIPATION

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Journal of Hydrodynamics 2001年第1期13卷 23-27页

作者： Hu, m.L. liang, z.C. zeng, Y.H. Wuhan Univ. of Hydraulic and Electr. Wuhan 430072 China

Bottom flow energy dissipation is one of the common energy dissipation methods for flood-releasing structures with high water head. measures of this energy dissipation depend mainly on the turbulent action of hydraulic jump. In this paper, the physical process and the calculating methods of the atomization caused by bottom flow energy dissipation were studied, the computation models of atomization quantity for the self-aerated flow in overflow and hydraulic jump regions are presented, and the main results are of theoretical and practical significance for the hydraulic and electric engineering.

关键词： Energy dissipation Hydraulic jump Hydrodynamics

Preparation Process and Properties of Porous Ecological Concrete

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武汉理工大学学报 2010年第17期32卷 256-260页

作者： liang L m YU H F PAN z F Department of Civil Engineering Nanjing University of Aeronautics &AstronauticsNanjing 210016China

By using waste bricks as aggregate,a kind of porous ecological concrete was prepared and the mixing technique and its properties were studied. Effects of the cement paste fluidity on workability of the porous ecological concrete were investigated,and influences of the water-cement ratio,the aggregate-cement ratio and the aggregate size on compressive strength and porosity of the porous ecological concrete were also discussed. Results show that for preparation of the porous ecological concrete,the aggregates should be enveloped with neat cement paste,and recommended fluidity of the cement paste is 200～235 mm. With the increasing of the aggregate-cement ratio,porosity of the porous ecological concrete increases while the 28 d compressive strength decreases. With increasing of the water-cement ratio,porosity of the porous ecological concrete decreases. And relationship between compressive strength and water-cement ratio of the porous ecological concrete does not follow Bolomey's formula. As a result of this study the porous ecological concrete is prepared,its porosity is 38.93%,the water absorption is 11.39% and the compressive strength is 1.14 mPa.

关键词： aggregate-cement ratio water-cement ratio aggregate size on fluidity of cement paste porous ecological concrete process of paste encapsulated stone porosity compressive strength

Thin-shell wormholes and modified Chaplygin gas with relativistic corrections

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Communications in Theoretical Physics 2023年第12期75卷 84-96页

作者： m z Bhatti z Yousaf m Yousaf Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

In this paper,we analyze thin-shell wormholes from two identical copies of charged static cylindrically symmetric spacetimes using Visser’s‘cut and paste’approach under the influence of f(R,T)gravity Harko,Lobo,Nojiri,and Odintsov(2011,***.D 84,024020).In this scenario,the modified Chaplygin gas supports the exotic matter in the shell which allows,one to examine the dynamics of constructed *** utilize the junction condition to connect the interior and exterior geometries across the hypersurface and calculate different components of the Lanczos equation recently computed by Roza in Rosa(2021,***.D 103,104069).We analyze the stability of the thin-shell wormhole models under linear perturbations while keeping the cylindrical symmetry and also examine the influence of charge on their *** positive quantity of the second derivative of potential at the throat radius might be interpreted as the stability *** find both unstable and stable wormhole solutions for different parameters included in the equation of state and specific forms of considered gravity and illustrate them theoretically as well as *** examine the impact of electric charge on the stability region of a constructed wormhole,which suggests that a wormhole model with a charge may exhibit more stable behavior compared to an uncharged system.

关键词： wormholes gravitation mathematical and relativistic aspects of cosmology

Complexity of charged anisotropic spherically symmetric fluids in f(G)gravity

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Communications in Theoretical Physics 2023年第3期75卷 91-104页

作者： z Yousaf m z Bhatti m m m Nasir Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The previous ideology of complexity factor for the dynamical spheres[Herrera et al 2018,***.D,98,104059]is extended for the influence of charge.A dynamical spherically symmetric non-dissipative and dissipative self-gravitating structure is examined in the presence of maxwell f(G)gravity to examine the complexity *** pattern of evolution is studied with the minimal complexity *** complexity factor remains the same for the structure of fluid distribution,while we examine homologous constraints for the most basic evolution *** calculate the structure scalars which play an important role in order to understand the fundamental properties of the *** fluid is geodesic as well as shearing for the dissipative case and there is a large number of *** the non-dissipative fluid distribution,a shear-free,homogeneous and isotropic,geodesic fluid correlates with the evolving homologous and vanishing complexity *** implication of the condition of vanishing complexity factor and stability are discussed at the end.

关键词： gravitation anisotropy complexity hydrodynamics

A pathway to improve low-cycle fatigue life of face-centered cubic metals via grain boundary engineering

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Journal of materials Science & Technology 2022年第18期113卷 82-89页

作者： X.J.Guan z.P.Jia S.m.liang F.Shi X.W.Li Department of materials Physics and Chemistry School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of materials Ministry of EducationNortheastern UniversityShenyang 110819China

To probe a pathway to improve the low-cycle fatigue life of face-centered cubic(FCC)metals via grain boundary engineering(GBE),the tension-tension fatigue tests were carried out on the non-GBE and GBE Cu-16 at.%Al alloys at relatively high stress *** results indicate that the cyclic strain localiza-tion and cracking at grain boundaries(GBs)can be effectively suppressed,especially at increased stress amplitude,by an appropriate GBE treatment that can result in a higher resistance to GB cracking and a greater capability of compatible ***,the sensitivity of fatigue life to stress amplitude can be weakened by GBE,and the low-cycle fatigue life of Cu-16 at.%Al alloys is thus distinctly improved.

关键词： Cu-Al alloy Grain boundary engineering Fatigue life Crack nucleation Stress amplitude

STUDY ON GRANULATION mECHANISmS OF γ+(Fe,mn)3C EUTECTICS IN AUSTENITE STEEL COmPOSITES

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Acta metallurgica Sinica(English Letters) 2003年第6期16卷 449-456页

作者： G.F.liang z.m.Xu Q.C.Jiang J.G.Li SchoolofmaterialsScienceandTechnology ShanghaiJiaotongUniversityShanghai200030China SchoolofmaterialsScience JilinUniversityChangchun130025China

Results presented in this paper contribute to investigation of the granulation mechanisms of γ+(Fe,mn)3C eutectics in the austenite matrix composites (abbreviated EAmC). The specimens corresponding to the nominal composition of eutectic with controlled RE(Ce)-mg agent modifier additions have been unidirectional solidified with a constant growth rate of 2.18μm/s at a fixed temperature gradient of 800K/cm using vertical Bridgeman method. With the RE-mg agent modifier, the transition of solid/liquid (S/L) interface from columnar to dendrite (CDT), refinement and developed branching of γ and (Fe,mn)3C phases in the eutectics, and the transition of growth style from faceted-nonfaceted (F/NF) to nonfaceted-nonfaceted (NF/NF) for γ and (Fe,mn)3C phases in the eutectic have been observed and investigated theoretically. Those can explain the granulation of γ+(Fe,mn)3C eutectics in the as cast because the roundness increases with the developed lateral branching of primary austenite dendrites, refinement of eutectics, and NF/NF growth of γ and (Fe,mn)3C phases in the eutectic.

关键词： composite RE-mg agent granulation unidirectional solidifica-tion

Correlation Between Local Atomic Symmetry and mechanical Properties in metallic Glasses

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Journal of materials Science & Technology 2014年第6期30卷 551-559页

作者： m.z.Li Department of Physics Renmin University of China Beijing Key Laboratory of Opto-Electronic Functional materials & micro-nano Devices Renmin University of China

The local atomic symmetry was investigated and discussed for understanding mechanical, vibrational and dynamical properties in metallic glasses. Local five-fold symmetry was defined based on the ratio of pentagons to the total number of faces in a Voronoi cluster analyzed by Voronoi tessellation method. It is found that the plastic deformation prefer to be initiated in the regions with less degree of local five-fold symmetry （LFFS） and propagate gradually toward the region with more degree of LFFS. On the other hand, the local structures having less degree of LFFS contribute more to the soft low-frequency modes, and thus the so-called boson peak, while those with more degree of LFFS participate more in moderate- and high- frequency modes in metallic glasses. The relationship between local atomic symmetry and structural heterogeneity, mechanical heterogeneity, and glass transition was also discussed. It is shown that local atomic symmetry could be a general structural indicator in metallic liquids and glasses for better understanding the structure-property relationship in amorphous alloys.

关键词： metallic glasses Atomic symmetry Deformation molecular dynamics