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Plasma Science and Technology 2017年第1期19卷 7-19页

作者： m g HAFEZ N C ROY m R TALUKDER m HOSSAIN ALI Department of of Applied mathematics University of Rajshahi Rajshahi-6205 Bangladesh Department of mathematics Chittagong University of Engineering and Technology Chittagong-4349Bangladesh Plasma Science and Technology Lab Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi-6205 Bangladesh

A comparative study is carried out for the nonlinear propagation of ion acoustic shock waves both for the weakly and highly relativistic plasmas consisting of relativistic ions and qdistributed electrons and *** Burgers equation is derived to reveal the physical phenomena using the well known reductive perturbation *** integration of the Burgers equation is performed by the（g￠/g）-expansion *** effects of positron concentration,ion–electron temperature ratio,electron–positron temperature ratio,ion viscosity coefficient,relativistic streaming factor and the strength of the electron and positron nonextensivity on the nonlinear propagation of ion acoustic shock and periodic waves are presented graphically and the relevant physical explanations are provided.

关键词： electron-positron-ion plasmas ion acoustic shock and periodic waves weakly and highly relativistic effects Burgers equation

multifaceted nature of membrane microdomains in colorectal cancer

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World Journal of gastroenterology 2011年第6期17卷 681-690页

作者： Kristina A Jahn filip Braet Australian Centre for microscopy and microanalysis The University of Sydney

membrane microdomains or lipid rafts are known to be highly dynamic and to act as selective signal transduction mediators that facilitate interactions between the cell's external and internal *** rafts play an important mediating role in the biology of cancer:they have been found in almost all existing experimental cancer models,including colorectal cancer (CRC),and play key regulatory roles in cell migration,metastasis,cell survival and tumor *** paper explores the current state of knowledge in this field by highlighting some of the pioneering and recent lipid raft studies performed on different CRC cell lines and human tissue *** this literature review,it becomes clear that membrane microdomains appear to be implicated in all key intracellular signaling pathways for lipid metabolism,drug resistance,cell adhesion,cell death,cell proliferation and many other processes in *** signal transduction pathways seem to originate directly from those peculiar lipid islands,thereby orchestrating the colon cancer cells' state and *** confirmed by recent animal and preclinical studies in different CRC models,continuing to unravel the structure and function of lipid rafts-including their associated complex signaling pathways-will likely bring us one step closer to better monitoring and treating of colon cancer patients.

关键词： Actin Caveolae Cytoskeleton Combined imaging Detergent-resistant membranes Drug targeting Electron microscopy Lipid domains membrane rafts Prognosis Staging Tomography Lipid-mediated therapy

The adsorption and corrosion inhibition of 8-hydroxy-7-quinolinecarboxaldehyde derivatives on C-steel surface in hydrochloric acid

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Chinese Journal of Chemical Engineering 2017年第9期25卷 1256-1265页

作者： A.m.Eldesoky S.g.Nozha Engineering Chemistry Department High Institute of Engineering & Technology Al-Qunfudah Center for Scientific Research (QCSR) Al-Qunfudah University College Umm Al-Qura University ministry of Health Domyat Laboratory

The protection influence of 8-hydroxy-7-quinolinecarboxaldehyde derivatives against C-steel corrosion was studied in 2 mol·L^(-1)HCl solutions at 30 °C. measurements were conducted under various experimental conditions using weight loss, potentiodynamic polarization, electrochemical impedance spectroscopy(EIS) and electrochemical frequency modulation(EFm) techniques. These studies have shown that 8-hydroxy-7-quinolinecarboxaldehyde derivatives are very good "green", mixed-type inhibitors. Corrosion rates obtained from both EFm and EIS methods are comparable with those recorded using Tafel extrapolation method, confirming validation of corrosion rates measured by the latter. The inhibitive action of these 8-hydroxy-7-quinolinecarboxaldehyde derivatives was discussed in terms of blocking the electrode surface by adsorption of the molecules through the active centers contained in their structures following Langmuir adsorption isotherm. Quantum chemical method was also employed to explore the relationship between the inhibitor molecular properties and its protection efficiency.

关键词： 8-Hydroxy-7-quinolinecarboxaldehyde derivatives C-steel HCl EFm

modeling and Simulation of microstructurally Small Crack Formation and growth in Notched Nickel-base Superalloy Component

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Journal of materials Science & Technology 2014年第3期30卷 203-212页

作者： g.m.Owolabi H.A.Whitworth Department of mechanical Engineering Howard University

Studies on microstructurally small fatigue cracks have illustrated that heterogeneous microstructural features such as inclusions, pores, grain size distribution as well as precipitate size distribution and volume fraction create stochasticity in their behavior under cyclic loads. Therefore, to enhance safe-life and damage-tolerance approaches, accurate modeling of the influence of these heterogeneous microstructural features on microstructurally small crack formation and growth from stress raisers is necessary. In this work, computational micromechanics was used to predict the high cycle fatigue of microstructurally small crack formation and growth in notched polycrystalline nickel-base superalloys and to quantify the variability in the driving force for formation and growth of microstructurally small crack from notch root in the matrix with non-metallic inclusions. The framework involves computational modeling to obtain three-dimensional perspectives of microstructural features influencing fatigue crack growth in notched nickel-base superalloys, which accounts for the effects of nonlocal notch root plasticity, loading, microstructural variability, and extrinsic defects on local cyclic plasticity at the microstructure-scale level. This approach can be used to explore sensitivity of minimum fatigue lifetime to microstructures. The simulation results obtained from this framework were calibrated to existing experimental results for polycrystalline nickel-base superalloys.

关键词： microstructuraliy small crack Crystal plasticity Nickel-base superalloy Fatigue life

SURFACE FINITE ELEmENTS FOR PARABOLIC EQUATIONS

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Journal of Computational mathematics 2007年第4期25卷 385-407页

作者： g. Dziuk C.m. Elliott Abteilung für Angewandte mathematik University of Freiburg Hermann-Herder-Straβe 10 D-79104Freiburg i. BrGermany Department of mathematics University of Sussex Falmer Brighton BN1 9RF United Kingdom

In this article we define a surface finite element method （SFEm） for the numerical solution of parabolic partial differential equations on hypersurfaces F in R^n＋1. The key idea is based on the approximation of F by a polyhedral surface Гh consisting of a union of simplices （triangles for n = 2, intervals for n = 1） with vertices on Г. A finite element space of functions is then defined by taking the continuous functions on Гh which are linear affine on each simplex of the polygonal surface. We use surface gradients to define weak forms of elliptic operators and naturally generate weak formulations of elliptic and parabolic equations on Г. Our finite element method is applied to weak forms of the equations. The computation of the mass and element stiffness matrices are simple and straightforward. We give an example of error bounds in the case of semi-discretization in space for a fourth order linear problem. Numerical experiments are described for several linear and nonlinear partial differential equations. In particular the power of the method is demorrstrated by employing it to solve highly nonlinear second and fourth order problems such as surface Allen-Cahn and Cahn-Hilliard equations and surface level set equations for geodesic mean curvature flow.

关键词： Surface partial differential equations Surface finite element method geodesic curvature Triangulated surface.

CFD Based Determination of Dynamic Stability Derivatives in Yaw for a Bird

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Journal of Bionic Engineering 2007年第4期4卷 201-208页

作者： m. A. moelyadi g. Sachs Aeronautics and Astronautics Department Bandung Institute of Technology Ganesha 10 40132 Bandung Indonesia Institute of Flight mechanics and Flight Control Technische Universitt München Boltzmannstrasse 15 85748 Garching Germany

Dynamic yaw stability derivatives of a gull bird are determined using Computational Fluid Dynamics（CFD） method. Two kinds of motions are applied for calculating the dynamic yaw stability derivatives CNr and CNβ. The first one relates to a lateral translation and, separately, to a yaw rotation. The second one consists of a combined translational and rotational motion. To determine dynamic yaw stability derivatives, the simulation of an unsteady flow with a bird model showing a harmonic motion is performed. The flow solution for each time step is obtained by solving unsteady Euler equations based on a finite volume approach for a small reduced frequency. Then, an evaluation of unsteady forces and moments for one cycle is conducted using harmonic Fourier analysis. The results of the dynamic yaw stability derivatives for both simulations of the model show a good agreement.

关键词： dynamic yaw stability CFD Fourier analysis unsteady aerodynamics reduced frequency

Sweet ionic liquids-cyclamates: Synthesis, properties, and application as feeding deterrents

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Science China Chemistry 2012年第8期55卷 1532-1541页

作者： PERNAK Juliusz WASINSKI Krzysztof PRACZYK Tadeusz NAWROT Jan CIENIECKA-ROSLONKIEWICZ Anna WALKIEWICZ filip mATERNA Katarzyna Poznan University of Technology Faculty of Chemical Technology pl. M. Sklodowskiej-Curie 2 60-965 Poznan Poland Plant Protection Institute-National Research Institute ul. Wegorka 20 60-318 Poznan Poland Institute of Industrial Organic Chemistry ul. Annopol 6 03-236 Warsaw Poland

In this paper, we show that sweet quaternary ammonium, pyridinium, and imidazolium cyclamates are cheap, thermally stable, surface and biologically active ionic liquids, with potential application as feeding deterrents.

关键词： ionic liquids cyclamates deterrents biological activity

Scaling of residual displacements in terms of elastic and inelastic spectral displacements for existing SDOF systems

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Earthquake Engineering and Engineering Vibration 2020年第1期19卷 71-85页

作者： m.g.Harikrishnan Vinay K.gupta Department of Civil Engineering Indian Institute of Technology Kanpur

Structures undergoing inelastic displacements during earthquake ground motions are known to sustain some amount of residual displacements, which may make them unusable or unsafe. In this study an attempt is made to estimate residual displacements for elastic-perfectly-plastic single-degree-of-freedom oscillators with a given lateral strength ratio. It is observed in the case of a class of ground motions that there are no trends in the dependence of residual displacement on the temporal features of the ground motion, and thus any estimation of residual displacements should be carried out only in the statistical sense. Statistical estimation of residual displacement spectrum via normalization with respect to inelastic or elastic spectral displacements is considered, and it is found that normalization with respect to inelastic spectral displacements is preferable. Expressions for residual displacement spectra are proposed for both types of normalizations and for the givenlateral-strength-ratio type oscillators.

关键词： residual displacement spectrum lateral strength ratio elastic-perfectly-plastic oscillator inelastic displacement spectrum elastic displacement spectrum horizontal ground motions

Hartree-Fock-Roothaan Calculations for ground States of Some Atoms Using minimal Basis Sets of Integer and Noninteger n-STOs

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Chinese Journal of Chemistry 2004年第11期22卷 1262-1266页

作者： gümü■ Sedat ZSO■AN Telhat Department of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEYDepartment of Physics Amasya Education Faculty Ondokuz Mayis University 05189 Amasya TURKEY

Hartree-Fock-Roothaan (HFR) calculations for ground states of some atoms, i.e. He, Be, Ne, Ar, and Kr have been performed using minimal basis sets of Slater type orbitals (STOs) with integer and noninteger principal quan-tum numbers (integer n-STOs and noninteger n-STOs). The obtained total energies for these atoms using minimal basis sets of integer n-STOs are in good agreement with those in the previous literature. On the other hand, for the case of minimal basis sets of noninteger n-STOs, although the calculated total energies of these atoms agree well with the results in literature, some striking results have been obtained for atoms Ar and Kr. Our computational re-sults for the energies of atoms Ar and Kr are slightly better than those in literature, by amount of 0.00222 and 0.000054 a.u., respectively. The improvement in the energies of atoms Ar and Kr may result from the efficient cal-culations of one-center two-electron integrals over noninteger n-STOs. For some atomic ions in their ground state, HFR calculations have been carried out using minimal basis sets of noninteger n-STOs. The obtained total energies for these atomic ions are substantially lower than those available in literature.

关键词： Hartree-Fock-Roothaan Slater type orbital

DISSOLUTION KINETICS OF PHOSPHATE ORE IN ACIDIC SOLUTIONS

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Chinese Journal of Chemical Engineering 1994年第2期2卷 13-22页

作者：马三剑 E.T.m.J.martynowicz g.J.Witkamp g.m.vanRosmalen Faculty of Chemical Technology and material Science Delft University of TechnologyLeeghwaterstraat 442628RZ DelftThe Netherlands

The dissolution kinetics of Florida and Jordan phosphate ore was studied in diluted nitric acid (0.2, 0.5, 1.0 mol ·L-1), and in phosphoric acid (55 wt% H3PO4) aqueous solutions. It was found that the hydrogen ions concentration is a controlling factor, but the calcium ions concentration can not affect the dissolution rate in the range of 0.0 and 2.0 wt% Ca2+. The effects of temperature, stirring intensity and the size of ore particles were also investigated. The transfer of hydrogen ion depends on the diffusion, while the calcium ions transfer is assumed to be depended on mechanically stripping. The shrinking core model with hydrogen ions diffusion control match the experimental results.

关键词： dissolution kinetics phosphate ore diffusion mechanically stripping hydrogen calcium ions concentration shrinking core model