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Neutron star cooling and GW170817 constraint within quark-meson coupling models

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chinese Physics c 2021年第2期45卷 535-551页

作者： Odilon Louren?o césar H.Lenzi Mariana Dutra Tobias Frederico M.Bhuyan Rodrigo Negreiros césar v.flores Guilherme Grams Débora P.Menezes Departamento de Física Instituto Tecnológico de Aeronáutica DCTA Department of Physics Faculty of Science University of Malaya Atomic Molecular and Optical Research Group Advanced Institute of Materials Science Ton Duc Thang University Faculty of Applied Sciences Ton Duc Thang University Instituto de Física Universidade Federal Fluminense 20420 centro de ciências Exatas Naturais e Tecnológicas UEMASUL Departamento de Física Universidade Federal de Santa Catarina FlorianópolisSC Univ.Lyon Univ.Claude Bernard Lyon 1

In the present work, we used five different versions of the quark-meson coupling(QMc) model to compute astrophysical quantities related to the GW170817 event and the neutron star cooling process. Two of the models are based on the original bag potential structure and three versions consider a harmonic oscillator potential to confine quarks. The bag-like models also incorporate the pasta phase used to describe the inner crust of neutron stars. With a simple method studied in the present work, we show that the pasta phase does not play a significant role. Moreover, the QMc model that satisfies the GW170817 constraints with the lowest slope of the symmetry energy exhibits a cooling profile compatible with observational data.

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Dendritic spine degeneration:a primary mechanism in the aging process

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Neural Regeneration Research 2025年第6期20卷 1696-1698页

作者： Gonzalo flores Leonardo Aguilar-Hernández Fernado García-Dolores Humberto Nicolini Andrea Judith vázquez-Hernández Hiram Tendilla-Beltrán Instituto de Fisiología Benemérita Universidad Autónoma de Puebla(BUAP)PueblaMexico Instituto de ciencias Forenses(INcIFO) Tribunal Superior de Justicia de la Ciudad de México(TSJCDMX).Mexico CityMexico Instituto Nacional de Medicina Genómica(INMEGEN) Mexico CityMexico

Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023).

关键词： aging process stress

Recent Advances in Synthesis and Properties of Hybrid Halide Perovskites for Photovoltaics

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Nano-Micro Letters 2018年第4期10卷 167-200页

作者： c.c.vidyasagar Blanca M.Muoz flores víctor M.Jimnez Prez Universidad Autónoma de Nuevo León Facultad de Ciencias Químicas Ciudad Universitaria School of Basic Sciences and Research in chemistry Rani Channamma University

The progress made by the scientific community in emerging photovoltaic technologies over the past two decades has been outstanding. Numerous methods have been developed for the preparation of hybrid organic–inorganic perovskite solar cells. The power conversion efficiency has been up to 14% by a one-step vacuum deposition technique. A serious concern is the toxicity of the materials. In this review, several methods aimed at resolving these problems to some extent have been compiled, including eco-friendly synthesis. Further efficiency enhancements are expected following optimization, and a better fundamental understanding of the internal electron charge transfer, electron–hole diffusion to the corresponding layers, flexibility, and stability-dependent bandgaps is reported. This paper explores the green synthesis of organic–inorganic perovskites for industrialization. concerning the above facts, a simple low-cost model called‘‘dispersed photovoltaic cells' ' is presented.

关键词： Perovskites Solar cells Organic–inorganic perovskites Synthetic routes Fluorescence

Morphological variation in the short-tailed fruit bat(carollia)in Ecuador,with comments on the practical and philosophical aspects of boundaries among species

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Integrative Zoology 2010年第3期5卷 226-240页

作者： Pablo JARRíN-v. cristina flores Janeth SALcEDO Yasuni Research Station School of Biological SciencesPontifical Catholic University of EcuadorQuitoEcuador center for Ecology and conservation Biology Department of BiologyBoston UniversityMassachusettsUSA central University of Ecuador School of Biology and ChemistryQuitoEcuador

The mechanisms for the morphological delimitation of species in carollia remain poorly *** is the first study to assess variation in size and shape from strictly geometric *** factors are assessed by statistical perspectives of distribution,overlap and relative *** its overlap,the size of the skull seems to be the most influential character for the discrimination of species,with shape playing a much smaller *** smallest species seems to be the most distinct in shape,not only in terms of distance among centroids in morphometric space,but also in the overall trend and direction of *** to previous studies,sexual dimorphism is not given by size but by distinct shapes of the *** such as the shape of the maxilla,previously described qualitatively as discrete with sharp boundaries,appear to be truly continuous with fuzzy borders among *** morphometric space is a gamut of continuous variation and overlap,the taxonomic error rate for size characters seems to be substantial for the medium-sized species(carollia brevicauda Schinz,1821),with approximately 30–40%of individuals erroneously assigned to a different species after a jackknifed discriminant *** taxonomic error is higher for shape ***,systematic and ecological consequences of the observed patterns of shape and size variation are commented within the context of previously proposed arguments and hypotheses.

关键词： boundaries carollia character state discriminant morphometrics

Dipole and generalized oscillator strength derived electronic properties of an endohedral hydrogen atom embedded in a Debye-Huckel plasma

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Matter and Radiation at Extremes 2018年第5期3卷 227-242页

作者： c.Martínez-flores R.cabrera-Trujillo Instituto de ciencias Físicas Universidad Nacional Autonoma de MexicoAp.Postal 43-8CuernavacaMorelos62251Mexico

We report electronic properties of a hydrogen atom encaged by an endohedral cavity under the influence of a weak plasma interaction. Weimplement a finite-difference approach to solve the Schrodinger equation for a hydrogen atom embedded in an endohedral cavity modeled by theWoods-Saxon potential with well depth v0, inner radius R0, thickness D, and smooth parameter g. The plasma interaction is described by aDebye-Hu¨ckel screening potential that characterizes the plasma in terms of a Debye screening length lD. The electronic properties of theendohedral hydrogen atom are reported for selected endohedral cavity well depths, v0, and screening lengths, lD, that emulate differentconfinement and plasma conditions. We find that for low screening lengths, the endohedral cavity potential dominates over the plasma interaction by confining the electron within the cavity. For large screening lengths, a competition between both interactions is observed. We assessand report the photo-ionization cross section, dipole polarizability, mean excitation energy, and electronic stopping cross section as function of lD and v0. We find a decrease of the Generalized Oscillator Strength (GOS) when the final excitation is to an s state as the plasma screeninglength decreases. For a final excitation into a p state, we find an increase in the GOS as the endohedral cavity well-depth increases. For the caseof the electronic stopping cross section, we find that the plasma screening and endohedral cavity effects are larger in the low-to-intermediateprojectile energies for all potential well depths considered. Our results agree well to available theoretical and experimental data and are afirst step towards the understanding of dipole and generalized oscillator strength dependent properties of an atom in extreme conditions encagedby an endohedral cavity immersed in a plasma medium.

关键词： Oscillator strengths Debye-Huckel plasma cavities Endohedral Energy loss Stopping power

Kcl:Eu^(2+) as a solar Uv-c radiation dosimeter. Optically stimulated luminescence and thermoluminescence analyses

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Journal of Rare Earths 2009年第4期27卷 579-583页

作者： I.Aguirre de cárcer H.L.D'Antoni M.Barboza-flores v.correcher F.Jaque Departamento Física de Materiales Universidad Autónoma Madrid Spain NASA Ames Research center Moffett Field California USA centro de Investig ción en Física Universidad de Sonora México centro Investigaciones Energía y Medioambientales (cIEMAT) Madrid Spain

The KcI：Eu2＋ system response to Uv-c was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It was found that after Uv-c ***, OSL was produced on a wide band of visible wavelengths with decay time that varied by several orders of magnitude depending on the Eu2＋ aggregation state. In spite of the low intensity of solar Uv-c reaching the Earth＇s surface in Madrid （40° N, 700 m a.s.1.）, it was possible to measure the Uv-c radiation dose at 6：48 solar time by using the TL response of the KcI：Eu2＋ system and differentiate it from the ambient beta radiation dose.

关键词： thermo-luminescence rare-earth-doped alkali halides solar ultraviolet dosimeter environmental radiation

Asphaltene Erosion Process in Air Plasma: Emission Spectroscopy and Surface Analysis for Air-Plasma Reactions

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Plasma Science and Technology 2012年第4期14卷 303-311页

作者： H.MARTINEZ O. flores J.c. POvEDA B. cAMPILLO Institute of Physical Sciences Autonomous National University of Mexico chemistry Faculty Autonomous National University of Mexico

Optical emission spectroscopy （OES） was applied for plasma characterization during the erosion of asphaltene substrates. An amount of 100 mg of asphaltene was carefully applied to an electrode and exposed to air-plasma glow discharge at a pressure of 1.0 Torr. The plasma was generated in a stainless steel discharge chamber by an ac generator at a frequency of 60 Hz, output power of 50 W and a gas flow rate of 1.8 L/min. The electron temperature and ion density were estimated to be 2.15±0.11 ev and （1.24±0.05）× 10^16 m^-3, respectively, using a double Langmuir probe. OES was employed to observe the emission from the asphaltene exposed to air plasma. Both molecular band emission from N2, N2＋, OH, cH, NH, O2 as well as cN, and atomic light emission from v and Hγ were observed and used to monitor the evolution of asphaltene erosion. The asphaltene erosion was analyzed with the aid of a scanning electron microscope （SEM） equipped with an energy dispersive X-ray （EDX） detector. The EDX analysis showed that the time evolution of elements c, O, S and v were similar and the chemical composition of the exposed asphaltenes remained constant. Particle size evolution was measured, showing a maximum size of 2307 μm after 60 min. This behavior is most likely related to particle agglomeration as a function of time.

关键词： asphaltene erosion surface analysis optical emission spectroscopy pulsedplasma glow discharge

Resveratrol effects on neural connectivity during aging

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Neural Regeneration Research 2016年第7期11卷 1067-1068页

作者： Gonzalo flores Rubén Antonio vázquez-Roque Alfonso Diaz Instituto de fisiología Benemerita Universidad autónoma de Puebla.14 Sur 6301PueblaMexico Departamento de Farmacia Facultad de Ciencias químicasbenemérita Universidad autónoma de PueblaPueblaMexico

Aging has been considered a natural process of any living *** rate of aging depends on many factors,including genetic and environmental *** this reason,many researchers in this field suggest that aging is an epigeneti... 详细信息

关键词： resveratrol connectivity older hippocampus neuronal metabolism cortical Aging cortex PPAR

cerium extraction by metallothermic reduction using cerium oxide powder injection

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Journal of Rare Earths 2011年第1期29卷 74-76页

作者： J.S.Luna A A.flores v R.Muiz v A.F.Fuentes J.Torres N.Rodríguez R J.c.Ortiz P.Orozco cINvESTAv Unidad Saltillo Saltillo-Monterrey Highway Km.13.5P.O.Box 66325000SaltilloCoahuilaMéxico Faculty of Engineering Autonomous Univer-sity of CoahuilaCamporedondo UnitSaltilloCoahuilaMéxico Department of Metal Mechanics Technological Institute of SaltilloV.Carranza Blvd 2400SaltilloCoahuilaZC 25280México Academic Unit of Engineering Autonomous University of CoahuilaLopez Velarde Av.ZacatecasZac.ZC 98060

This work presented the feasibility of cerium recovery by Al-Mg alloy through the metallothermic reduction of ceO2 to obtain a master alloy Al-4%ce. The master alloy obtained in this investigation was for the grain refinement and modification of Al-Si alloys. The reagent was incorporated into a molten alloy using the submerged powder injection technique, and metallic samples were obtained during injection. chemical and microstructural analyses （by inductively coupled plasma （IcP） and scanning electron microscopy （SEM）, respectively） confirmed the possibility of ce uptake in the bath （0 to 4 wt.%）, as ceO2 was reduced through metallothermic reactions in the molten alloys. Based on the characterization of reaction products, the sequence of the reaction was proposed.

关键词： cerium recovery metallothermic reduction reaction products rare earths