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Three-dimensional biomagnetic maxwell fluid flow over a stretching surface in presence of heat source/sink

International journal of Biomathematics 2019年第3期12卷 207-226页

作者： m.G.murtaza m.Ferdows j.C.misra e.e.Tzirtzilakis Research Group of Fluid Flow modeling and Simulation Department of Applied mathematics University of Dhaka Dhaka-1000 Bangladesh Centre for Theoretical Studies Indian Institute of Technology Kharagpur Kharagpur 721302 India Fluid Dynamics & Turbomachinery Laboratory Department of mechanical engineering Technological educational Institute of Western Greece 1 m. Aleksandrou Str Koukouli 26334 Patras Greece

The present paper deals with the study of three-dimensional boundary layer flow of biomagnetic maxwell fluid over a plane horizontal surface stretched linearly along two mutually perpendicular directions. Basic principles of magnetohydrodynamics (mHD) and ferro-hydrodynamics (FHD) have been employed. The effect of heat generation/absorption has been taken into consideration. The study is theoretical and is conducted by using a combination of approximate and numerical techniques. By using the method of similarity transformation, the governing nonlinear partial differential equations are converted into a set of coupled ordinary differential equations. In the sequel, a suitable numerical method has been developed to solve the coupled differential equations. The accuracy of the numerical method has been checked by comparing the numerical results with those of an earlier study reported in available literatures. effects of various parameters involved in the study, viz. the magnetohydrodynamic and ferromagnetic parameters, Deborah number, stretching ratio and heat generation on the fluid flow profiles are investigated and the results have been presented graphically. Variations of the skin friction, heat transfer rate and relative wall pressure with change in hydrodynamic and ferromagnetic parameters have also been illustrated. It is found that due to the influence of the Kelvin force, the velocity component in xx-direction is greater than the corresponding one in the hydrodynamic case, but the opposite is true for the velocity component in the yy-direction. We also found that the temperature of the fluid for hydrodynamic flow is greater than that for mHD or FHD flow. It is even greater for BFD flows. The numerical results of the study reveal that the characteristics of blood flow are significantly affected by the presence of a magnetic field.

关键词： Biomagnetic fluid magnetic dipole magnetization heat transfer stretching surface

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microstructural Development and mechanical Properties of Pm Ti-45Al-2Nb-2mn-0.8 vol.%TiB_2 Processed by Field Assisted Hot Pressing

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journal of materials Science & Technology 2014年第11期30卷 1145-1154页

作者： R.munoz-moreno e.m.Ruiz-Navas B.Srinivasarao j.m.Torralba Department of materials Science and engineering Universidad Carlos Ⅲ de MadridAvda.Universidad 3028911 LeganésMadridSpain ImDeA materials Institute C/Eric Kandel 228906 GetafeMadridSpain

A γ-TiAI intermetallic alloy, Ti-45Al-2Nb-2mn （at.%）-0.8 vol.%TiB2, has been processed from gas atomized praalloyed powder by field assisted hot pressing （FAHP）. An initial analysis of the prealloyed powder helped on the understanding of the intermetallic sintering behavior. Atomized powder consisted of α metastable phase that transformed into α2＋γ equilibrium phases by thermal treating. Different powder particle microstructures were found, which influence the microstructure development of the FAHP T-TiAI material depending on the sintering temperature. Duplex, nearly lamellar and fully lamellar microstructures were obtained at the sintaring temperatures above 1000 ℃. Lower consolidation temperatures, below 1000 ℃, led to the formation of an AI rich phase at powder particle boundaries, which is deleterious to the mechanical properties. High compressive yield strength of 1050 mPa was observed in samples with FAHP duplex microstructures at room temperature. Whereas nearly lamellar and fully lamellar microstructures showed yield strength values of 655 and 626 mPa at room temperature and 440 and 425 mPa at 750 ℃, respectively, which are superior in comparison to similar alloys processed by other techniques. These excellent properties can be explained due to the different volume fractions of the α2 and γ phases and the refinement of the Pm microstructures.

关键词： Titanium aluminides Powder metallurgy microstructure mechanical properties Field assisted sintering

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Adsorption properties of Rosmarinus officinalis oil as green corrosion inhibitors on C38 steel in 0.5 m H_2SO_4

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Acta metallurgica Sinica(english Letters) 2010年第1期23卷 13-20页

作者： e.el Ouariachi j.Paolini m.Bouklah A.elidrissi A.Bouyanzer B.Hammouti j-m.Desjobert j.Costa Laboratoire de Chimie Appliqu'ee et environnement Facult'e des SciencesUniversit'e Mohamed PremierBP71760000 OujdaMorocco UmR CNRS 6134 Laboratoire de Chimie des Produits NaturelsUniversit'e de CorseFrance

Rosmarinus officinalis essential oil obtained by hydrodistillation was tested as corrosion inhibitor of steel in 0.5 m H2SO4 using weight loss measurements, and electrochemical .polarisation methods. Results obtained indicate that the corrosion rate is reduced and R. officinalis oil adsorbs on the metal surface and then inhibits corrosion process. Its inhibition efficiency increases with oil increasing content to reach 61% at 1 g/L. Polarisation curves indicate that RO acts as a cathodic inhibitor. The inhibition efficiency of naturally oil remains slightly constant with the rise of temperature. Chemical analysis of R. officinalis essential oil was carried out using capillary GC and GC/mS. The oil composition was characterized by high amount of oxygenated monoterpene （77%） with 1,8-cineol （52.1%） as main component. Discussion of adsorption was investigated on the the isotherm adsorption of essential oil on basis of essential oil composition. Finally the steel has been also reported.

关键词： Rosmarinus officinalis oil Adsorption Corrosion Inhibition Steel 1,8-cineol

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H∞ synchronization of chaotic neural networks with time-varying delays

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Chinese Physics B 2013年第11期22卷 244-252页

作者： O. m. Kwon m. j. Park ju H. Park S. m. Lee e. j. Cha School of electrical engineering Chungbuk National University Department of electrical engineering Yeungnam University School of electronic engineering Daegu University Department of Biomedical engineering School of Medicine Chungbuk National University

In this paper, we investigate the problem of H∞ synchronization for chaotic neural networks with time-varying delays. A new model of the networks with disturbances in both master and slave systems is presented. By constructing a suitable Lyapunov–Krasovskii functional and using a reciprocally convex approach, a novel H∞ synchronization criterion for the networks concerned is established in terms of linear matrix inequalities （LmIs） which can be easily solved by various effective optimization algorithms. Two numerical examples are given to illustrate the effectiveness of the proposed method.

关键词： chaotic neural networks time-varying delays H∞ synchronization Lyapunov method

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Capsule endoscopy in suspected small bowel Crohn's disease:economic impact of disease diagnosis and treatment

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World journal of Gastroenterology 2009年第45期15卷 5685-5692页

作者： jonathan A Leighton Ian m Gralnek Randel e Richner michael j Lacey Frank j Papatheofanis Division of Gastroenterology and Hepatology Mayo Clinic ScottsdaleAZ 85259United States Rappaport Faculty of medicine Technion-Israel Institute of Technology GI Outcomes Unit Departments of Gastroenterology and Ambulatory Care Services Rambam Health Care Campus The Neocure Group SherbornMA 01770 United States Division of Health Policy Departments of Radiology and Economics University of California San DiegoSan Diego CA 92103United States

AIm: To model clinical and economic benef its of capsule endoscopy (Ce) compared to ileo-colonoscopy and small bowel follow-through (SBFT) for evaluation of suspected Crohn’s disease (CD). meTHODS: Using decision analytic modeling, total and yearly costs of diagnostic work-up for suspected CD were calculated, including procedure-related adverse events, hospitalizations, off ice visits, and medications. The model compared Ce to SBFT following ileo-colonoscopy and secondarily compared Ce to SBFT for initial evaluation. ReSULTS: Aggregate charges for newly diagnosed, medically managed patients are approximately $8295. Patients requiring aggressive medical management costs are $29 508; requiring hospitalization, $49 074. At sensitivity > 98.7% and specifi city of > 86.4%, Ce is less costly than SBFT. CONCLUSION: Costs of Ce for diagnostic evaluationof suspected CD is comparable to SBFT and may be used immediately following ileo-colonoscopy.

关键词： Capsule endoscopy Costs Crohn's disease Disease management

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Weak Continuity of Riemann Integrable Functions in Lebesgue-Bochner Spaces

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Acta mathematica Sinica,english Series 2010年第2期26卷 241-248页

作者： j.m.CALABUIG j.RODRíGUeZ e.A.SNCHeZ-PReZ Instituto Universitario de matemlica Pura y Aplicada Universidad Politcnica de Valencia

In general, Banach space-valued Riemann integrable functions defined on [0, 1] （equipped with the Lebesgue measure） need not be weakly continuous almost everywhere. A Banach space is said to have the weak Lebesgue property if every Riemann integrable function taking values in it is weakly continuous almost everywhere. In this paper we discuss this property for the Banach space LX^1 of all Bochner integrable functions from [0, 1] to the Banach space X. We show that LX^1 has the weak Lebesgue property whenever X has the Radon-Nikodym property and X＊ is separable. This generalizes the result by Chonghu Wang and Kang Wan [Rocky mountain j. math., 31（2）, 697-703 （2001）] that L^1[0, 1] has the weak Lebesgue property.

关键词： Riemann integral Bochner integral Lebesgue-Bochner space weak Lebesgue property

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Paleoecological Response of Corals to the end-Triassic mass extinction： An Integrational Analysis

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journal of earth Science 2018年第4期29卷 879-885页

作者： George D Stanley jr Hannah m e Shepherd Autumn j Robinson University of montana Paleontology Center Missoula MT 59812 USA

The end-Triassic （also Triassic-jurassic） mass extinction severely affected life on planet earth 200 million years ago. Paleoclimate change triggered by the volcanic eruptions of the Central Atlantic magmatic Province （CAmP） caused a great loss of marine biodiversity, among which 96% coral genera were get lost. However, there is precious little detail on the paleoecology and growth forms lost between the latest Triassic extinction and the early jurassic recovery. Here a new pilot study was conducted by analyzing corallite integration levels among corals from the latest Triassic and early jurassic times. Integration levels in corals from the Late Triassic and early jurassic were determined through both the Paleobiology Database as well as from a comprehensive museum collection of fossil corals. Results suggest that in addition to a major loss of diversity following the end-Triassic mass extinction, there also was a significant loss of highly integrated corals as clearly evidenced by the coral data from the early jurassic. This confirms our hypothesis of paleoecological selectivity for corals following the end-Triassic mass extinction. This study highlights the importance of assigning sim- ple to advanced paleoecological characters with integration levels, which opens a useful approach to understanding of mass extinction and the dynamics of the recovery.

关键词： coral loss integration level end-Triassic mass extinction paleoecology

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Hysteresis loop behaviors of ferroelectric thin films: A monte Carlo simulation study

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Chinese Physics B 2015年第11期24卷 492-496页

作者： C.m.Bedoya-Hincapié H.H.Ortiz-varez e.Restrepo-Parra j.j.Olaya-Flrez j.e.Alfonso PCm Computational Applications Universidad Nacional de Colombia Univesidad Santo Tomás Universidad de Caldas AFIS Análisis de Fallas Integridad y Superficies Universidad Nacional de Colombia Grupo de Ciencia de materialesy superficies Departamento de Física Universidad Nacional de Colombia

The ferroelectric response of bismuth titanate Bi4Ti3O12 （BIT） thin film is studied through a monte Carlo simulation of hysteresis loops. The ferroelectric system is described by using a Diffour Hamiltonian with three terms： the electric field applied in the z direction, the nearest dipole-dipole interaction in the transversal （x-y） direction, and the nearest dipole-dipole interaction in the direction perpendicular to the thin film （the z axis）. In the sample construction, we take into consideration the dipole orientations of the monoclinic and orthorhombic structures that can appear in BIT at low temperature in the ferroelectric state. The effects of temperature, stress, and the concentration of pinned dipole defects are assessed by using the hysteresis loops. The results indicate the changes in the hysteresis area with temperature and stress, and the asymmetric hysteresis loops exhibit evidence of the imprint failure mechanism with the emergence of pinned dipolar defects. The simulated shift in the hysteresis loops conforms to the experimental ferroelectric response.

关键词： ferroelectrics bismuth titanate hysteresis loop dipolar defects

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Alternatives for large-scale production of cultured beef: A review

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journal of Integrative Agriculture 2015年第2期14卷 208-216页

作者： matilda S m moritz Sanne e L Verbruggen mark j Post Department of Physiology Maastricht UniversityMaastricht 6229 ER The Netherlands Department of Physics Chemistry and Biology Linkping UniversityLinkping SE-581 83 Sweden

Cultured beef is a method where stem cells from skeletal muscle of cows are cultured in vitro to gain edible muscle tissue. For large-scale production of cultured beef, the culture technique needs to become more efficient than today＇s 2-dimensional（2D） standard technique that was used to make the first cultured hamburger. Options for efficient large-scale production of stem cells are to culture cells on microcarriers, either in suspension or in a packed bed bioreactor, or to culture aggregated cells in suspension. We discuss the pros and cons of these systems as well as the possibilities to use the systems for tissue culture. either of the production systems needs to be optimized to achieve an efficient production of cultured beef. It is anticipated that the optimization of large-scale cell culture as performed for other stem cells can be translated into successful protocols for bovine satellite cells resulting in resource and cost efficient cultured beef.

关键词： cultured beef microcarriers aggregated cells packed bed bioreactor cell culture

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Velocity-Based moving mesh methods for Nonlinear Partial Differential equations

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Communications in Computational Physics 2011年第8期10卷 509-576页

作者： m.j.Baines m.e.Hubbard P.K.jimack Department of mathematics The University of ReadingRG66AXUK. School of Computing University of LeedsLS29JTUK

This article describes a number of velocity-based moving mesh numerical methods for multidimensional nonlinear time-dependent partial differential equations(PDes).It consists of a short historical review followed by a detailed description of a recently developed multidimensional moving mesh finite element method based on *** element algorithms are derived for both mass-conserving and non mass-conserving problems,and results shown for a number of multidimensional nonlinear test problems,including the second order porous medium equation and the fourth order thin film equation as well as a two-phase *** applications and extensions are referenced.

关键词： Time-dependent nonlinear diffusion moving boundaries finite element method Lagrangian meshes conservation of mass

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