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Acoustic streaming and Sun's meridional circulation

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Research in Astronomy and Astrophysics 2016年第9期16卷 101-106页

作者： jose manuel Valverde Faculty of Physics University of Seville

A vast number of physical processes involving oscillations of a bounded viscous fluid are relevantly influenced by acoustic streaming. When this happens a steady circulation of fluid develops in a thin boundary adjacent to the interface. Some examples are refracted sound waves, a fluid inside a spherical cavity undergoing torsional oscillations or a pulsating liquid droplet. Steady streaming around circular interfaces consists of a hemispherically symmetric recirculation of fluid from the equatorial plane to the polar axes closely resembling the meridional circulation pattern observed in the Sun＇s convection zone that determines the solar cycle. In this paper, it is argued that the acoustic pulsations exhibited by the Sun would lead to acoustic streaming in the boundary of the convection zone. A simple estimation using a typical dominant frequency of 3 mHz and the observed surface oscillation amplitude yields a steady streaming velocity Us - 10 m s^-1, which is on the order of the meridional circulation velocity observed in the Sun＇s convection zone.

关键词： Sun general -- Sun helioseismology -- Sun granulation -- Sun oscillations -- Sun fun-damental parameters -- Sun activity

Magnetic field assisted fluidization:A modified Richardson-Zaki equation

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China Particuology 2007年第1期5卷 61-70页

作者： jose manuel Valverde Antonio Castellanos Faculty of Physics Universidad de Sevilla Avenida Reina Mercedes s/n 41012 Sevilla Spain

Magnetic particles can be uniformly fluidized by coupling the gas flow with an externally imposed magnetic field. Interparticle forces generated by the magnetic field cause aggregation of the particles in chain-like structures preferentially oriented along the magnetic field lines. In the present paper, we study the implications of the formation of these special types of aggregates on the empirical Richardson-Zaki （RZ） equation, originally proposed to describe the expansion of fluidized beds of non-aggregated particles. We have addressed two important issues, namely the flow regime, which is a function of the size of the aggregates, and the effect of shape and orientation of the chain-like aggregates with respect to gas flow on fluid drag. We propose a modified RZ equation （MRZE） in which the velocity scale, given by the terminal settling velocity of the individual aggregates, and the RZ exponent are predetermined as a function of the chain length. The chain length depends on the ratio of the magnetic energy to gravitational energy, and is estimated from the magnetic field intensity, and particle magnetization, size and density. Predictions of the MRZE are successfully compared with published results in the literature on the expansion of magnetic particles in the presence of externally applied magnetic fields.

关键词： Fluidization Geldart B Magnetic particles Aggregation Richardson-Zaki equation

Critical evaluation of transit policies in Lima,Peru;resilience of rail rapid transit(Metro)in a developing country

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Green Energy and Intelligent Transportation 2024年第5期3卷 23-33页

作者： manuel jose Martinez Representante Legal Instituto de Avance del Transporte Peruano EIRLCalle Schrader 179dpto.202Lima 41San BorjaLimaPeru

This paper evaluates rail transit within the context of the transit policies implemented in Lima,*** it reviews the implementation of rapid transit,and bus ***,it evaluates the outcomes of such policies by using Total Factor Productivity for policy effectiveness,Data Envelopment Analysis for rapid transit performance,and Generalized Cost of Travel for *** paper finds that implementation failed in enforcing key requirements for rail transit regarding penetration of CBD and short transfers to bus transit;and that the basic assumptions of bus reform did not hold regarding bus oversupply,bus congestion or bus *** paper also finds that outcomes of policies failed dramatically in achieving the planning goals;however,rail transit(Metro)shows high level of resilience in serving large ridership at high *** the other hand,bus reform was associated with a disproportionate increase of motorization,well over the effect of income growth or car attractiveness,and more related to the excessive reduction of bus transit capacity ill-advised from unproved bus reform *** paper recommends expanding rail rapid transit due to its intensive use of green renewable energy and its potential of demand growth if combined with modern Intelligent Transportation services,but this opportunity can be wasted without the proposed policy constraint to achieve lower Generalized Cost of Travel at any governmental intervention for bus reform,instead of just reducing bus transit capacity as ***,this paper recommends government to government contracts to build rail transit and to enforce proper planning.

关键词： Public transportation Bus rapid transit Rail transportation Bus transit Developing countries Resilient

Kinetic and morphology study of alginate-vineyard pruning waste biocomposite vs. non modified vineyard pruning waste for dye removal

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Journal of Environmental Sciences 2015年第12期27卷 158-167页

作者： Xanel Vecino Rosa devesa-Rey Salvador Villagrasa jose M.Cruz Ana B.Moldes Chemical Engineering Department School of Industrial Engineering (EEI)University of VigoCampus As Lagoas-Marcosende Defense University Center Naval AcademyUniversity of Vigo Materials Engineering Department School of Industrial Engineering (EEI)University of VigoCampus As Lagoas-Marcosende

In this work a comparative bioadsorption study between a biocomposite consisting of hydrolysed vineyard pruning waste entrapped in calcium alginate spheres and non entrapped vineyard residue was carried *** have demonstrated that the biocomposite based on lignocellulose-calcium alginate spheres removed 77.3% of dyes,while non entrapped lignocellulose eliminated only removed 27.8% of colour *** experimental data were fitted to several kinetic models（pseudo-first order,pseudo-second order,Chien-Clayton model,intraparticle diffusion model and Bangham model）; being pseudo-second order the kinetic model that better described the adsorption of dyes onto both *** addition,a morphological study（roughness and shape） of alginate-vineyard biocomposite was established under extreme conditions,observing significant differences between hydrated and dehydrated alginate-vineyard *** techniques used to carry out this morphological study consisted of scanning electron microscopy（SEM）,perfilometry and 3D surface analysis.

关键词： Immobilized alginate-vineyard Dyes Kinetic studies Roughness Spherical shape

Contrasting size-dependent life history strategies of an insular lizard

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Current Zoology 2020年第6期66卷 625-633页

作者： Andreu Rotger jose manuel Igual Giacomo Tavecchia Animal Demography and Ecology Unit GEDAIMEDEA(CSIC-UIB)c M.Marques 2101790EsporlesSpain

In many species with continuous growth,body size is an important driver of life-history tactics and its relative importance is thought to reflect the spatio-temporal variability of selective *** developed a deterministic size-dependent integral projection model for 3 insular neighboring lizard populations with contrasting adult body sizes to investigate how size-related selective pressures can influence lizard life-history *** each population,we broke down differences in population growth rates into contributions from size-dependent body growth,survival,and feeundity.A life table response experiment(LTRE)was used to compare the population dynamics of the 3 populations and quantify the contributions of intrinsic demographic coefficients of each population to the population growth rate(z).Perturbation analyses revealed that the largest adults contributed the most to the population growth rate,but this was not true in the population with the smallest adults and size-independent *** we were not able to identify a single factor responsible for this difference,the combination of the demographic model on a continuous trait coupled with an LTRE analysis revealed how individuals from sister populations of the same species follow different life strategies and showed different compensatory mechanisms among survival,individual body growth,and *** results indicate that body size can play a contrasting role even in closely-related and closely-spaced populations.

关键词： body size capture-recapture integral projection model Lilfords lizard size-dependent mortality

The role of solvents in the formation of methylammonium lead triiodide perovskite

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Journal of Energy Chemistry 2022年第5期31卷 393-400页

作者： Junke Jiang jose manuel Vicent-Luna Shuxia Tao Materials Simulation andModelling.Department of Applied Physics Eindhoven University of Technology.Eindhoven 5600 MB.the Netherlands Center for Computational Energy Research Department of Applied PhysicsEindhoven University of Technology.Eindhoven 5600 MB.the Netherlands

Metal halide perovskites(MHPs) are gaining increasing attention as low-cost, high-performance semiconductors for optoelectronics. In particular, their solution processing is compatible with the largescale manufacturing of thin-film devices, including solar cells and light-emitting *** the coordination chemistry in precursor-solvent solution and atomistic mechanisms of film formation is of great importance for optimizing the optoelectronic properties of the final *** the methylammonium lead triiodide(MAPbI_(3)) as an example, we study the complex evolution of the molecular species from the solution to the initial stage of the crystallization by using a combination of density functional theory(DFT) calculations and ab-initio molecular dynamics(AIMD) simulations. We focus on the widely employed solvents DMSO and DMF, analyze the structures and energies of the iodoplumbate complexes in the form of simple complex of [PbI_(m)L_(n)]^(2-m))_(x) and polymeric iodoplumbates of([PbI_(m)L_(n)]^(2-m))_(x). Based on the calculated formation enthalpies, we propose reaction schemes of MAPbI_(3) formation in DMSO, DMF and DMF-DMSO binary solvent and explain the advantages of the binary *** highlight the important role of NH...O hydrogen bonds in the formation of iodoplumbates *** calculations indicate unbalanced reaction energies at several elementary reaction steps in either DMF(formation of [PbI_(4)L_(n)]^(2-) being highly favourable) or DMSO(formation of [PbI_(5)L_(n)]^(3- )being retarded).Mixing a small amount of DMSO in DMF gives rise to a better balance in the energies and, therefore,potentially better equilibria in the overall crystallization process and better quality of the final perovskite films.

关键词： MAPbI_(3) Perovskite formation Solvents DFT

Unexplained liver laceration after metastasis radiofrequency ablation

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World Journal of Gastroenterology 2009年第40期15卷 5103-5105页

作者： Esther Ua Javier Trueba jose manuel Montes Medical Oncology Service Clinical University Hospital of Valladolid Radiology Service Clinical University Hospital of Valladolid

Many studies have established the role of radiofrequency (RF) ablation as a minimally invasive treatment for liver metastases. Although relatively safe, several complications have been reported with the increased use of RF ablation. We describe here a case of unexplained liver laceration after a RF procedure. A woman who presented a solitary metachronous liver metastasis underwent RF ablation treatment for this lesion. Six hours later the patient displayed fatigue and pallor. Emergency blood tests showed a haemoglobin level of < 7 g/dL and markedly elevated transaminase levels. A computed tomography examination revealed two areas of liver laceration with haematoma, one of them following the path of the needle and the other leading away from the f irst. Following a blood transfusion, the patient was haemodynamically stable and completely recovered 24 h later. The patient remained in bed for 1 wk. No surgical intervention was required, and she was discharged 1 wk later.

关键词： Colon cancer Liver haemorrhage Liver laceration Liver metastases Radiofrequency ablation

Phenolic compounds of green tea: Health benefits and technological application in food

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 709-719页

作者： jose manuel Lorenzo Paulo Eduardo Sichetti Munekata Meat Technological Center of Galicia Galicia Street No.4 Parque Tecnolgico de Galicia San Cibrao das Vinas Department of Food Engineering Faculty of Animal Science and Food Engineering University of Sao Paulo

Green tea has been an important beverage for humans since ancient times, widely consumed and considered to have health benefits by traditional medicine in Asian countries. Green tea phenolic compounds are predominately composed of catechin derivatives, although other compounds such as flavonols and phenolic acids are also present in lower proportion. The bioactivity exerted by these compounds has been associated with reduced risk of severe illnesses such as cancer, cardiovascular and neurodegenerative diseases. Particularly, epigallocatechin gallate has been implicated in alteration mechanisms with protective effect in these diseases as indicated by several studies about the effect of green tea consumption and mechanistic explanation through in vitro and in vivo experiments. The biological activity of green tea phenolic compounds also promotes a protective effect by antioxidant mechanisms in biological and food systems, preventing the oxidative damage by acting over either precursors or reactive species. Extraction of phenolic compounds influences the antioxidant activity and promotes adequate separation from green tea leaves to enhance the yield and/or antioxidant activity. Application of green tea phenolic compounds is of great interest because the antioxidant status of the products is enhanced and provides the product with additional antioxidant activity or reduces the undesirable changes of oxidative reactions while processing or storing *** this scenario, meat and meat products are greatly influenced by oxidative deterioration and microbial spoilage, leading to reduced shelf life. Green tea extracts rich in phenolic compounds have been applied to increase shelf life with comparable effect to synthetic compounds, commonly used by food industry. Green tea has great importance in general health in technological application, however more studies are necessary to elucidate the impact in pathways related to other diseases and food applications.

关键词： Phenolic profile Healthy Neurodegenerative diseases Extraction of polyphenols Antioxidant mechanism Food stability

Contributions to data transmission at critical moments on unmanned aerial vehicles

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Chinese Journal of Aeronautics 2023年第8期36卷 247-257页

作者： jose Enrique RODRIGUEZ David SEGURADO manuel SANCHEZ jose Javier MARTINEZ Rafael GONZALEZ National Institute of Aerospace Technology Madrid 28850Spain Department of Computer Science University of AlcalaAlcala de HenaresMadrid 28054Spain

As for unmanned aircraft, the knowledge of the aircraft performance is directly related with the navigation, guidance, and control system programming. Therefore, the measured data in each phase of the flight must be sufficiently precise to obtain a good characterization of *** article proposes new methods of sending information to ground, which make it possible to know the aircraft behavior accurately, and for this purpose, four contributions have been made for ALO(Avión Ligero de Observación, Spanish acronym for Light Observation Aircraft). Currently, the characterization is based on data obtained at ten samples per second, insufficient to acquire detailed knowledge of what happened during the whole flight of an aircraft. As a result of these contributions, many more samples per second of accelerations and angular velocities are obtained at the most critical moments of the flight, such as takeoff or landing. Among the improvements included are data compression techniques, providing references to locate the measured data in time and identifying labels of each parameter.

关键词： Critical moments Data transmission Datacompression tech-niques Radio-modem Recommended Standard 232(RS-232) Unmannedaerial vehicle