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Particuology 2017年第4期15卷 129-137页

作者： Carlos M. Romero Luna Luis R. Carrocci Gretta L.A.F. Arce Ivonete avila UNESP - Sflo Paulo State University School of Engineering Department of Energy Laboratory of Combustion and Carbon Capture (LC3) CEP 12.516-410 Guaratinguetd SP Brazil INPE - Brazilian Space Research Institute Combustion and Propulsion Associated I.aboratory CEP 12.630-000 Cachoeira Paulista SP Brazil UNJFSC -Jose Faustino Sanchez Carrion National University Faculty of Chemical and Metallurgical Engineering Advanced Materials and Nanotechnology Research Group Huacho Lima Peru

In simulations of fluidized beds using computational fluid dynamics （CFD）, the description of gas-solid flow hydrodynamics relies on a drag model to account for the momentum transfer between gas and solid phases. Although several studies of drag models have been published, there have been few investigations of the application of lattice Boltzmann method （LBM）-based drag models to bubbling fluidized bed simu- lations. In the present study, a comprehensive comparison of empirical and LBM-based drag models was carried out to assess the performance of these models during simulations of gas-solid flow hydrodynam- ics in a bubbling fluidized bed. A CFD model using the MFIX code based on the Eulerian-Eulerian approach and the kinetic theory of granular flow was used to simulate a 2D bubbling fluidized bed with Geldart B particles. The simulation results were validated by comparison with experimental data. Statistical anal- ysis of the results shows that LBM-based drag models can reliably model gas-solid flow hydrodynamics in a bubbling fluidized bed.

关键词： CFD Drag model Gas-solid flow hydrodynamics Bubbling fluidized bed

The Abbreviated Symbol of Living Forms, Unit and Growth

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Fudan Journal of the Humanities and Social Sciences 2016年第3期9卷 465-491页

作者： Humberto ortega-Villasenor Genaro Quinones Trujillo Department of Literary Studies University of Guadalajara Sierra de Tapalpa #1336 (EntreIxtepete y Cuicuilco) Col. Pinar de La Calma C.P. 45080 Zapopan Jalisco Mexico Industrial Technological System DGETI-Jalisco Ministry of Public Education Paseo de lasMagnolias #1966 (Entre Paseo de los Cafetos y Paseo de los Granados) FraccionamientoTabachines MExico C.P. 45188 Zapopan Jalisco Mexico

This essay is written in the form of a mosaic. It intersperses simple language, primary and secondary quotes within text, footnotes and epigraphs from classical thinkers and cutting-edge researchers. It invites readers, be they casual or experienced, to a certain play of irony and fantasy in their reflection on the main thrust of the argument. The essay is divided into two parts. The first seeks to introduce the readers to some of the main concerns of frontier science and the Philosophy of Science at the beginning of this millennium： the Universe Models proposed by scientists from fields related to Physics and Mathematics in their eagerness to explain more and more discoveries and to lay out a solid new scientific paradigm. We are convinced that the leap between sidelines and insides--when confronting straightforward style with systematic contrast--does not lessen the rigor of research, and serves to lighten the density of the topic by projecting nuances and resonance onto the logos and its concatenation. It may also serve to vivify field and figure, in order to recreate the fertile delight that generally comes from a good reading of deep *** the second part, we attempt to subtly demonstrate a fortunate discovery： the validity and solidity of the laws of Nature, upheld on the basis of their abstract mathematical expression （the Number Phi （φ）, the goldennumber or golden section）, which despite having faded into oblivion, buried under centuries of disuse in the fields of Aesthetics and Art, has proven to be useful as a critical instrument and a template for concrete solutions that we wish to share. We believe that this Model may serve not only to answer some of the scientific issues that we have referred to, but to redirect the discussion itself, and break the logjam of many frontier forums that place conditions on the application of the Models pro- duced over the last century. Having glimpsed those realms where analysis and common sense come together for ad

关键词： Universe models Scientific paradigm Mathematical expression Number Phi

Implant surface features as key role on cell behavior

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BIOCELL 2022年第5期46卷 1151-1156页

作者： RAFAEL SCAF DE MOLON MARTA MARIA ALVES PEREIRA ERICA DORIGATTI DE avila Federal University of Rio de Janeiro Rio de Janeiro21941-617Brazil São Paulo State University Araraquara14801-930Brazil

It has been recognized that physical and chemical properties of biomaterial surfaces mediate the quality of extracellular matrix(ECM)that may affect cell *** nature,ECM is a heterogeneous three-dimensional superstructure formed by three major components,glycosaminoglycan,glycoconjugate,and protein,that anchors cellular compartments in tissues and regulates the function and the behavior of *** in the biointerface alter the quality of ECM and morphology through cell surface receptors,which,in turn,enable it to trigger specific cell signaling and different cellular *** fact,a number of strategies have been used to improve the functionality of surfaces and direct cell behavior through precisely designed ***,we aimed to discuss,through a science-based viewpoint,the biomaterial surface features on cell behavior and analyze the impact of cell physical modification on dental implant development.

关键词： Biomaterial Cell adhesion Surface chemistry Surface topography

Quantum nonlocal effects in individual and interacting graphene nanoribbons

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Light(Science & Applications) 2015年第1期4卷 513-517页

作者： Ivan Silveiro Juan Manuel Plaza ortega F Javier Garcia de Abajo ICFO-Institut de Ciencies Fotoniques Mediterranean Technology Park08860 Castelldefels(Barcelona)Spain ICREA-Institucio Catalana de Recerca i Estudis Avanc¸ats Passeig Lluis Companys 2308010 BarcelonaSpain

We show that highly doped graphene ribbons can support surface plasmons at near-infrared frequencies when their width is in the nanometer range,leading to important nonlocal and finite quantum-size corrections,such as sizable *** magnitude of these effects is assessed by comparing classical and quantum-mechanical models to describe graphene *** precisely,we examine individual and interacting 6–8 nm wide zigzag and armchair ribbons doped to 0.4–1.5 eV Fermi *** find a strong influence of nonlocal effects on the orientation of graphene edges,with plasmons in zigzag ribbons undergoing strong quenching when their energy is below the Fermi *** is also affecting the hybridization between ribbon plasmons in dimers and arrays for separations below a few ***,the removal of a single row of atomic bonds in a ribbon produces a strong plasmon frequency shift,whereas the removal of bonds along an array of rows separated by several nanometers in an extended sheet causes a dramatic increase in the *** the fundamental interest of these results,our work supports the use of narrow ribbons to achieve electro-optical modulation in the near infrared.

关键词： graphene graphene plasmons graphene ribbons metamaterials plasmonics

Fabrication and characterisation of random and aligned electrospun scaffolds to investigate hypothalamic stem/progenitor cell behaviour

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Engineered Regeneration 2024年第1期5卷 11-20页

作者： Selina Beal Iain Stewart Paul Hatton Marysia Placzek Ilida ortega School of Clinical Dentistry and Insigneo Institute Claremont CrescentUniversity of SheffieldSheffield S102TAUK School of Biosciences University of SheffieldEnglandUK National Heart and Lung Institute Imperial CollegeLondon SW36LYUK

Tanycytes are stem/progenitor cells that reside in the hypothalamus of the adult vertebrate *** can be cultured as free-floating neurospheres in vitro but tend to spontaneously differentiate over *** we asked whether morphological cues provided by engineered polymer scaffolds can modify spontaneous ***-derived neurospheres were cultured on electrospun scaffolds,prepared with either random or aligned fiber *** dispersed widely on the scaffolds,and-on aligned scaffolds-were highly organized,orientated parallel to the *** analysis showed that cells cultured on aligned scaffolds showed significantly greater expression of the neural stem/progenitor cell marker,NrCAM and reduced expres-sion of differentiated cell markers in comparison to those cultured on random *** this shows that tanycytes respond to local engineered cues,and that a morphologically constrained environment can better main-tain tanycytes as stem *** aligned scaffold culture system provides a powerful tool to better investigate this novel stem/progenitor cell population.

关键词： Scaffold Tanycytes Neural stem/progenitor cells Fiber alignment Electrospinning

Λ■ production in p collis

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Chinese Physics C 2010年第9期34卷 1462-1464页

作者： P.G.ortega D.R.Entem F.Fernández Grupo de ísica Nuclear and IUFFyM Universidad de Salamanca

We describe the production of Λ Λ in pp collisions using a constituent quark model which has been successfully applied to the N N system.

关键词： non-relativistic quark model hyperon-antihyperon production

Enhanced magnetic modulation of light polarization exploiting hybridization with multipolar dark plasmons in magnetoplasmonic nanocavities

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Light(Science & Applications) 2020年第1期9卷 1547-1560页

作者： Alberto Lopez-ortega Mario Zapata-Herrera Nicolo Maccaferri Matteo Pancaldi Mikel Garcia Andrey Chuvilin Paolo Vavassori CIC nanoGUNE-BRTA Donostia-San SebastianDonostia 20018Spain Department of Physics and Materials Science University of LuxembourgL-1511 LuxembourgLuxembourg Department of Physics Stockholm University10691 StockholmSweden IKERBASQUE Basque Foundation for ScienceBilbao 48013Spain

Enhancing magneto-optical effects is crucial for reducing the size of key photonic devices based on the non-reciprocal propagation of light and to enable active ***,we disclose a currently unexplored approach that exploits hybridization with multipolar dark modes in specially designed magnetoplasmonic nanocavities to achieve a large enhancement of the magneto-optically induced modulation of light *** broken geometrical symmetry of the design enables coupling with free-space light and hybridization of the multipolar dark modes of a plasmonic ring nanoresonator with the dipolar localized plasmon resonance of the ferromagnetic disk placed inside the *** hybridization results in a low-radiant multipolar Fano resonance that drives a strongly enhanced magneto-optically induced localized *** large amplification of the magneto-optical response of the nanocavity is the result of the large magneto-optically induced change in light polarization produced by the strongly enhanced radiant magneto-optical dipole,which is achieved by avoiding the simultaneous enhancement of reemitted light with incident polarization by the multipolar Fano *** partial compensation of the magnetooptically induced polarization change caused by the large re-emission of light with the original polarization is a critical limitation of the magnetoplasmonic designs explored thus far and that is overcome by the approach proposed here.

关键词： polar light enable

Insights on the crosstalk between dendritic cells and helper T cells in novel genetic etiology for mendelian susceptible mycobacterial disease

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Cellular & Molecular Immunology 2018年第12期15卷 1091-1094页

作者： Emma Rey-Jurado Magdalena S.Pizarro-ortega Alexis M.Kalergis Millennium Institute on Immunology and Immunotherapy Departamento de Genética Molecular y MicrobiologíaFacultad de Ciencias BiológicasPontificia Universidad Católica de ChileSantiago 8330644Chile Departamento de Endocrinología Facultad de MedicinaPontificia Universidad Católica de ChileSantiago 8330644Chile

Mendelian susceptibility to mycobacterial disease(MSMD)is an inherited predisposition to infections by Bacille-Calmette Guérin(BCG)vaccine or by environmental *** etiology of MSMD has been associated with up to nineteen different genetic mutations in interferon(IFN)-γ-related genes.1 Although mycobacteria susceptibility-associated genetic mutations are rare in the population,their diagnosis is crucial for an efficient and timely *** et al.2 have recently described an autosomal recessive deficiency in the signal peptidase-like 2 A(SPPL2-a)as a new genetic etiology for MSMD in three patients that had suffered BCG dissemination disease.

关键词： mendelian susceptibility to mycobacterial disease SPPL2a deficiency cDC2 mycobacterial-specific priming IFN-γ

Optimal Coordinated Operation of Distributed Static Series Compensators for Wide-area Network Congestion Relief

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1374-1384页

作者： Camilo Andres Ordonez M Antonio Gomez-Exposito Guillermo EVinasco M Jose Maria Maza-ortega IEEE Smart Wires Union CityUSA Department of Electrical Engineering University of SevilleSevillaSpain Interconexion Electrica SA Intercolombia Sevilla Spain

Relieving network congestions is a critical goal for the safe and flexible operation of modern power systems, especially in the presence of intermittent renewables or distributed generation. This paper deals with the real-time coordinated operation of distributed static series compensators(DSSCs) to remove network congestions by suitable modifications of the branch reactance. Several objective functions are considered and discussed to minimize the number of the devices involved in the control actions, the total losses or the total reactive power exchanged, leading to a non-convex mixed-integer non-linear programming problem. Then, a heuristic methodology combining the solution of a regular NLP with k-means clustering algorithm is proposed to get rid of the binary variables, in an attempt to reduce the computational cost. The proposed coordinated operation strategy of the DSSCs is tested on several benchmark systems, providing feasible and sufficiently optimal solutions in a reasonable time frame for practical systems.

关键词： Distributed static series compensation(DSSC) flexible AC transmission system(FACTS) mixed-integer non-linear programming(MINLP) wide-area network control

Welfare and Market Impacts of Food Safety Measures in China: Results from Urban Consumers' Valuation of Product Attributes

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Journal of Integrative Agriculture 2014年第6期13卷 1404-1411页

作者： David L. ortega H. Holly Wang Nicole J. Olynk Widmar Department of Agricultural Foodand Resource EconomicsMichigan State University Department of Agricultural Economics Purdue University

This study provides an economics assessment of various food safety measures in China. A choice experiment approach is used to elicit Chinese consumer preferences for various food safety attributes using data from a 2008 urban consumer survey. An alternative welfare calculation is used to model aggregate market impacts of select food safety measures. Our results show that the largest welfare gains are found in the current government-run certiifcation program. The implementation of a third-party certiifcation system, a traceability network and a product label would generate signiifcant value and would help reduce current system inefifciencies in China. This study builds on previous research and provides an alternative approach for calculating consumer valuation of safety and quality attributes that can be used to estimate aggregate economic and welfare impacts.

关键词： food safety consumer welfare food policy China