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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

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

Petiveria alliacea Suppresses Airway Inflammation and Allergen-Specific Th2 Responses in Ovalbumin-Sensitized Murine Model of Asthma

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Chinese Journal of Integrative Medicine 2018年第12期24卷 912-919页

作者： Rosa Martha Perez Gutierrez Jose Maria Mota.flores Natural Products Research Laboratory Higher School of Chemical Engineering and Extractive IndustriesInstituto Politecnico Nacional (IPN) Professional Unit Adolfo Lopez Mateos Av. Instituto Politécnico NacionalS/N

Objective： To examine the effect of metanol extract of Petiveria alliacea （PM） on airway inflammation in a murine model of chronic asthma. Methods： Two-month-old male BALB/c mice （n=6-8/group） were sensitized on days 0 and 14 by intraperitoneal injection of 20μg ovalbumin （OvA）. On day 25, the mice received an airway challenge with OvA （3%, w/v, in phosphate buffered saline）. PM was administered orally by oral gavage to mice at doses of 100, 200 and 400 mg/kg body weight once daily from days 18 to 23. Control mice were orally administered phosphate buffered saline （PBS） to induce a model of asthma. At the end of the test, respiratory reactivity was assayed, the total cell number, interleukin-4 （IL-4）, IL-5, IL-13, tumor necrosis factor-alpha （TNF-α） and reactive oxygen species （ROS） in the bronchoalveolar lavage fluid （BALF） were determined and the levels of serum IgE, intercellular cell adhesion molecule 1 （ICAM-1） and eotoxin were measured. In addition, lung tissue was used to qualify the IL-4, IL-5, IL-13, TNF-α and transforming growth factor beta 1 （TGF-β1）. Histologic examination was performed to observe inflammatory cellular infiltration. Results： The administration of PM in comparison with the OvA-only treated group significantly attenuated the infiltration of eosinophUs and other inflammatory cells （P〈0.01）. Airway resistance （RI） in the OvA-only induced group was significantly higher than that of the PBS control group （P〈0.01） when methacholine was added. TNF-α, IgE, TGF-β1 and cytokine levels IL-4, IL-5, IL-β in the BALF decreased compared to control mice （P〈0.01 or P〈0.05）. PM treatment also inhibited the production of chemokines, eotaxin and ICAM-1 in BALF （P〈0.01）, which improved lung function. Histopathological examination revealed that the sensitized treated PM groups had significant lower in inflammatory scores similar to dexamethasone treatments and the untreated group. Conclusion： Administration of PM could inhibit airway inflammation, regulate cyt

关键词： Petiveria alliacea allergy antiinflammation asthma

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

Downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid

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Journal of Integrative Plant Biology 2010年第2期52卷 244-251页

作者： María Josefa López Núez-flores Jorge Gutirrez Laura v.Gómez-Ros Esther Novo Uzal Mariana Sottomayor Alfonso Ros Barceló Department of Plant Biology University of MurciaE-30100MurciaSpain Department of Plant Biology University of La CoruaE-15071La CorunaSpain IBMC University of Porto4150 PortoPortugal

Hypocotyl formation during the epigeal germination of seedlings is under strict hormonal regulation. In a 3 d old Zinnia elegans seedling system, gibberellic acid （GA3） exerts an opposite effect to that exerted by light on hypocotyl photomorphogenesis because GAz promotes an etiolated-like growth with an inhibition of radial （secondary） growth. For this reason, the effect of GA3 on the basic peroxidase isoenzyme from Z. elegans （ZePrx）, an enzyme involved in hypocotyl lignin biosynthesis, was studied. The results showed that GA3 reduces ZePrx activity, similarly to the way in which it reduces seedling secondary growth. This hormonal response is supported by the analysis of the ZePrx promoter, which contains four types of GA3-responsive ***： the W Box/O2S; the Pyr Box; the GARE; and the Amy Box. Taken together, these results suggest that ZePrx is directly regulated by GA3, with this effect matching the inhibitory effect of GA on the hypocotyl secondary growth.

关键词： GA Downregulation of the Basic Peroxidase Isoenzyme from Zinnia elegans by Gibberellic Acid cis Figure

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

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 531-547页

作者： Odilon Lourenço 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 AeronáuticaDCTA12228-900São Josédos CamposSPBrazil Department of Physics Faculty of ScienceUniversity of MalayaKuala Lumpur 50603Malaysia Atomic Molecular and Optical Research Group Advanced Institute of Materials ScienceTon Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam Instituto de Física Universidade Federal Fluminense 20420NiteróiRJBrazil Centro de Ciências Exatas Naturais e TecnológicasUEMASULRua Godofredo Viana 1300Centro CEP:65901-480ImperatrizMaranhãoBrazil Departamento de Física Universidade Federal de Santa CatarinaFlorianópolisSCCP 476CEP 88.040-900Brazil Univ.Lyon Univ.Claude Bernard Lyon 1CNRS/IN2P3IP2I LyonUMR 5822F-69622VilleurbanneFrance

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 *** of the models are based on the original bag potential structure and three versions consider a harmonic oscillator potential to confine *** bag-like models also incorporate the pasta phase used to describe the inner crust of neutron *** a simple method studied in the present work,we show that the pasta phase does not play a significant ***,the QMC model that satisfies the GW170817 constraints with the lowest slope of the symmetry energy exhibits a cooling profile compatible with observational data.

关键词： equation of state compact star cooling in stars quark-meson coupling models tidal deformability neutron star merger

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

Addition of phenolic compounds to bread: antioxidant benefits and impact on food structure and sensory characteristics

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Food Production, Processing and Nutrition 2021年第1期3卷 314-325页

作者： Yesica A.Czajkowska–González Emilio Alvarez–Parrilla Nina del Rocío Martínez–Ruiz Alma A.vázquez–flores Marcela Gaytán–Martínez Laura Ade la Rosa Departament of Chemical Biological Sciences Institute of Biomedical SciencesUniversidad Autónoma de Ciudad JuárezAnillo Envolvente del PRONAF y Estocolmos/nC.P.32310 Cd.JuárezMéxico Programa de Posgrado en Alimentos del Centro de la República(PROPAC) Research and Graduate Studies in Food ScienceSchool of ChemistryUniversidad Autónoma de QuerétaroCentro UniversitarioCerro de las Campanas S/NC.P.76010 Santiago de QuerétaroMexico

The use of flours or phenolic extracts obtained from non-traditional sources or agri-food industry by-products has been a strategy used to formulate new bakery products with characteristics of a functional ***,phenolic compounds present great structural diversity,as well as the ability to interact in a complex way with the macromolecules that constitute the bread ***,the addition of these flours,extracts or pure compounds produces various effects on the microstructure of bread,and several of its sensory *** is mainly due to interactions between phenolic compounds and gluten *** objective of this review is to analyze some of the most recent published works on the addition of phenolic compounds in wheat bread to identify the type of positive and negative effects that have been observed and how they can be related to the physicochemical interactions between phenolic compounds and the macromolecules that constitute the food matrix,mainly *** effect of monomeric and polymeric phenolic compounds on the strength of these interactions and on the properties of dough and bread are discussed.

关键词： condensed tannins hydrolysable tannins phenolic acids gluten food rheology food texture protein-phenolic interactions disulfide bonds non-covalent interactions