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Journal of Wuhan University of Technology(Materials Science) 2018年第6期33卷 1293-1297页

作者： KESHTKAR Javad VARGAS GARCIA Jorge Roberto GALAVIZ PErez Jorge MARTINEZ TRINIDAD José Escuela Superior de Ingenieria Mecánica y Eléctrica Instituto Politécnico NacionalMéxico07738CDMXMéxico Escuela Superior de Ingenieria Quimica e Industrias Extractivas Instituto Politécnico NacionalMéxico07738CDMXMéxico universidad juárez autònoma de tabasco DivisiònAcadémica Multidisciplinaria de Jalpa de MéndezRibera AltaJalpa de MéndezTabasco86205México

Al-doped ZnO(AZO) powders were prepared by using metal chloride precursors and the sol-gel technique. IR peaks observed at 1590 cm-1 and 1620 cm-1indicated the formation of metal chelate as a consequence of the addition of acetylacetone to the metal chloride solution. TG-DSC analysis of the AZO gels confirmed the formation of metal chelate as evidenced by the development of several weight loss peaks accompanied by the introduction of new endothermic peaks. The resulting AZO gels were annealed at 500, 600, and 800 ℃ to study the effect of annealing temperature. XRD and SEM results showed that crystallization of AZO gels takes place around 600 ℃. Hexagonal wurtzite structure was identified as the main phase for all the samples. In addition, small shift of the XRD(002) peak coupled with XPS results from the AZO powders confirmed the successful doping of the ZnO powders. Micron sized rod-like AZO powders were uniform in dimension and morphology and remained stable even at 800 ℃.

关键词： aluminum doped ZnO rod-like metal chloride sol gel acetylacetone

Rainfall Trend Analysis in the City of Villahermosa, Mexico

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Journal of Geological Resource and Engineering 2019年第1期7卷 9-16页

作者： Ana Victoria Gómez Alejandro Heliodoro Daniel Cruz Suárez División Académica de Ciencias Básicas Universidad Juárez Autónoma de Tabasco Cunduacán 86690 México

In this paper, a study by means of linear regression of rainfall in Villahermosa is proposed, within the study area 5 meteorological stations distributed in the city were analyzed because it is one of the most populated areas of the state, once estimated the data, the non-parametric Mann-Kendall test was used to determine increasing or decreasing linear trends in precipitation. To determine the usefulness of statistical inference, the linear correlation coefficient (r) was calculated, which was 0.86 on average. Statistical efficiency (E) was also calculated, which in all the cases analyzed suggests the viability of statistical inference. As a result of this analysis, a complete rainfall database is presented and evaluated for increasing or decreasing trends for the 1980-2010 period.

关键词： Rainfall linear regression Mann Kendall trend analysis.

A charged star with geometric Karmarkar condition

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Communications in Theoretical Physics 2023年第8期75卷 139-149页

作者： Gabino Estevez-delgado Joaquin Estevez-delgado Rafael Soto-Espitia Antonio Rendón Romero Jorge Mauricio Paulin-Fuentes Facultad de Químico Farmacobiología de la universidad Michoacana de San Nicolás de Hidalgo Facultad de Ciencias Físico Matemáticas de la universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad Universitaria Facultad de Ingeniería Civil de la universidad Michoacana de San Nicolás de Hidalgo Edificio A Ciudad Universitaria Facultad de Ingeniería Mecánica de la universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad Universitaria División Académica de Ciencias Básicas de la universidad juárez autónoma de tabasco

In this paper,we analyse an analytical solution of the Einstein–Maxwell field equations that considers matter with anisotropic pressures in a static and spherically symmetric geometry.We report the manner in which we obtained the solution,which is by means of the Karmarkar condition.For the model,we assume a state equation that describes the interaction of matter from quarks P=(c^(2)ρ-4B_(g))/3 and we consider the presence of electric charge,which can generate that the radial and tangential pressures are not equal.In a graphic manner,we analyse the physical properties of the model,taking as the observational data those of mass 1M⊙and radius7.69 km which were reported for the star Her X-1.The charge values are found between 5.57×10^(18)C≤Q≤1.31×10^(20)C and the interval of the Bag constant Bg∈[118.7,122.13]MeV/fm^(3).Also,we show the stability of the configuration by means of the static stability criteria of Harrison–Zeldovich–Novikov((?M)/?ρc>0),as well as in regards to infinitesimal radial adiabatic perturbation,since the adiabatic indexγ>3.3 which guarantees the stability of the solution.

关键词： general relativity exact solutions anisotropic fluid Karmarkar condition

Macroscopic Quantum Behaviour of Periodic Quantum Systems

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Journal of Modern Physics 2014年第1期5卷 44-50页

作者： A. Martín-Ruiz J. Bernal Adrián Carbajal-Domínguez Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. Mexico universidad juárez autónoma de tabasco División Académica de Ciencias Básicas Cunduacán México

In this paper we introduce a simple procedure for computing the macroscopic quantum behaviour of periodic quantum systems in the high energy regime. The macroscopic quantum coherence is ascribed to a one-particle state, not to a condensate of a many-particle system;and we are referring to a system of high energy but with few degrees of freedom. We show that, in the first order of approximation, the quantum probability distributions converge to its classical counterparts in a clear fashion, and that the interference effects are strongly suppressed. The harmonic oscillator provides a testing ground for these ideas and yields excellent results.

关键词： Matrix density Quantum Interference Classical Limits

Relativistic charged stellar modeling with a perfect fluid sphere

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Communications in Theoretical Physics 2023年第9期75卷 113-121页

作者： Joaquin Estevez-delgado Joel Arturo Rodríguez Ceballos Jorge Mauricio Paulin-Fuentes JoséVega Cabrera Antonio Rendón Romero Facultad de Ciencias Físico Matemáticas de la universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad UniversitariaMorelia MichoacánCP 58040Mexico Facultad de Químico Farmacobiología de la universidad Michoacana de San Nicolás de Hidalgo Tzintzuntzan No.173Col.MatamorosMorelia MichoacánC.P.58240Mexico División Académica de Ciencias Básicas de la universidad juárez autónoma de tabasco Carretera Cunduacán-Jalpa Km.1Col.La Esmeralda86690CunduacánTabascoMexico Facultad de Ingenieria Mecanica de la universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad UniversitariaCP 58030Morelia MichoacánMexico

In this report we present the generalization of a solution to Einstein's equations with perfect fluid for the case of Einstein–Maxwell with perfect fluid.The effect of the charge is reflected by a parameter,ν,and its interval is determined by the positivity condition from the pressure in the interior of the star.It is shown that the solution is stable according to the Zeldovich criteria as well as in relation to the criteria of the adiabatic index.The compactness,u=GM/c^(2)R,of this charged model is greater than it is for the chargeless case as a result of the effect of the presence of the charge.This allows it to represent stars with a high compactness,in particular a graphic analysis is presented for the star SAX J1808.4-3658 with mass M=1.435M_(⊙)and radius R=7.07 km.From these data and employing the solution,we obtain that the total maximum charge for the star is Q=2.4085×10^(20)C.

关键词： general relativity exact solutions charged fluid stars models

Interlayer distance effects on absorption coefficient and refraction index change in p-type double-δ-doped GaAs quantum wells

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Chinese Physics B 2019年第12期28卷 186-190页

作者： H Noverola-Gamas L M Gaggero-Sager O Oubram Instituto de Investigaciones en Ciencias Básicas y Aplicadas Universidad Autónoma del Estado de Morelos MorelosCuernavaca 62209Mexico Division Academica de Ingeniería y Arquitectura Universidad Juárez Autonoma de TabascoCunduacan 8660Mexico Centro de Investigación en Ingeniería y Ciencias Aplicadas Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico Facultad de Ciencias Químicas e Ingeniería Universidad Autónoma del Estado de MorelosCuernavaca 62209Mexico

In the framework of the Thomas–Fermi(TF) approach, a model for the p-type double-δ-doped(DDD) system in Ga As is presented. This model, unlike other works in the literature, takes into account that the Poisson equation associated with the system is nonlinear. The electronic structure is calculated for heavy and light holes. The changes in the electronic structure result of the distance d between the doped layers are studied. In particular, the relative absorption coefficient as well as the relative refractive index change is calculated as a function of the incident photon energy for heavy holes. The effect of the interlayer distance exhibits, in the absorption coefficient, a red shift of the peak position and a decrease in amplitude when the distance increases. In addition, the relative refractive index change node has a red shift as well as the interlayer distance increases. The calculations show that the effect of the separation between layers has a greater influence on the linear terms. These results are very important for theoretical calculations and engineering of optical and electronic devices based in δ-doped Ga As.

关键词： double delta-doping p-type GaAs layers electronic structure Thomas–Fermi approach nonlinear optical properties

Effect of <i>Carica papaya</i>Leaf Extract on Serum Lipids and Liver Metabolic Parameters of Rats Fed a High Cholesterol Diet

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Health 2015年第9期7卷 1196-1205页

作者： Alma M. Zetina-Esquivel Carlos A. Tovilla-Zárate Crystell Guzmán-Garcia Arturo Rodríguez-Hernández Andrés E. Castell-Rodríguez Jorge L. Ble-Castillo Angela Avila-Fernandez Isela E. juárez-Rojop juan C. Díaz-Zagoya Centro de Investigación División Académica de Ciencias de la Salud Universidad Juárez Autónoma de Tabasco Villahermosa México División Académica Multidisciplinaria de Comalcalco Universidad Juárez Autónoma de Tabasco Comalcalco México Unidad de Medicina Familiar 10 Instituto Mexicano del Seguro Social Xalapa México División de Investigación Facultad de Medicina Universidad Nacional Autónoma de México México D. F. México

Hyperlipidemia plays an important role in the development of atherosclerosis, the main cause of death in the world. In this study, the lipid-lowering effect of Carica papaya leaf in rats fed with a high cholesterol diet was evaluated. Daily doses of C. papaya extract 0, 31, 62 or 125 mg/kg body weight were orally administered in 300 μl polyethylene glycol to hypercholesterolemic rats;it was also administered 62 mg/kg body weight of the extract to rats with normal diet. After a 20-day treatment, the animals were sacrificed;blood and liver were analyzed. Hypercholesterolemic rats showed an increased serum and liver cholesterol, triacylglycerols, and atherogenic index. The C. papaya extract produced a significant decrease of serum and liver cholesterol concentrations in hypercholesterolemic rats, but did not modify serum or liver triacylglycerols;however, the extract reduced the atherogenic index in a dose-dependent manner. C. papaya treatment decreased LDL-C and increased HDL-C in serum significantly. When the oxygen consumption was evaluated in phosphorylating and resting states, the respiratory control in hypercholesterolemic rats mitochondria was lower than in normal diet rats. However, a higher respiratory control in hypercholesterolemic rats mitochondria was observed after C papaya treatment. The liver morphological data are in accordance with serum and liver biochemical values. Our data support that C. papaya has a significant hypocholesterolemic action and HDL-C raising effect on rats fed with a cholesterol-rich diet, however, the precise metabolites responsible of this effect remain unknown.

关键词： Serum Lipids Carica papaya Cholesterol Mitochondria

Diabetic Patients develop Greater Intensity of Postoperative Pain than Non-Diabetics after Open Cholecystectomy: A Pilot Study

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Journal of Biosciences and Medicines 2021年第6期9卷 67-75页

作者： Rocío Adriana Martínez-Alpuche Erick Mauricio Brindis-Fuentes Crystel Guadalupe Guzmán-Priego Francisco Valenzuela-Priego Leonor Ivonne Parra-Flores Jorge Elías Torres-López Pain Mechanisms Laboratory División Académica de Ciencias de la Salud Universidad Juárez Autónoma de Tabasco Villahermosa Tabasco México department of Anaesthesiology Hospital Regional de Alta Especialidad “Dr. Juan Graham Casasús” Villahermosa Tabasco México

Background: Pre-clinical and clinical studies have shown that inflammatory pain intensity is increased under diabetes condition. Open cholecystectomy (OC) is a surgical procedure with predictable postoperative pain. However, the comparison of postoperative pain due to open cholecystectomy in diabetic and non-diabetic patients remains unknown. The research question to answer was whether diabetic patients undergoing OC development greater intensity of postoperative pain than non-diabetic patients. Methods: The study was conducted between june 2016 and February 2018 at the Regional Hospital of High Specialty “Dr. juan Graham Casasús” of Villahermosa, tabasco, Mexico. Seventy patients in two groups of 35 patients each scheduled for OC under general anesthesia were studied. Pain was assessed using the 11-point numerical rating scale (NRS). The primary endpoint was to know NRS pain scores after awaking of general anesthesia. Secondary outcomes included the time of onset of pain and comparing NRS scores between diabetic and non-diabetic patients undergoing OC. Results: Diabetic patients reported significantly greater intensity pain than non-diabetic patients. The mean overall pain score in the diabetic and non-diabetic patients was 7.2 ± 0.3 and 5.3 ± 0.3 (P = 0.0002), respectively. Furthermore, 60% of diabetic patients had severe pain (NRS ≥ 8) compared to 20% of non-diabetics (P = 0.006). The time to onset postoperative pain was about 35 minutes in both groups (P = 0.876). Conclusions: Diabetic patients undergoing OC have greater intensity postoperative pain and also more frequency of patients with severe pain scores compared with non-diabetic patients. Therefore, analgesic treatment in those patients should consider this point in order to provide a satisfactory postoperative analgesia.

关键词： Postoperative Pain Inflammatory Pain Cholecystectomy Diabetes Observational Study

Influence of the starter culture on the volatile profile of processed cocoa beans by gas chromatography–mass spectrometry in high resolution mode

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Food Bioscience 2022年第3期47卷 595-603页

作者： K.G.Alvarez-Villagomez C.A.Ledesma-Escobar F.Priego-Capote V.J.Robles-Olvera P.García-Alamilla Unidad de Investigación y desarrollo en Alimentos TecNM/Instituto Tecnológico de VeracruzMiguel Ángel de Quevedo 2779VeracruzVer.Mexico Academic Division of Agriculture and Livestock Science Universidad Juárez Autónoma de TabascoCarreteraVillahermosa-Teapa Km 25La HuastecaCentroTabasco86280Mexico department of Analytical Chemistry Campus of RabanalesUniversity of CordobaSpain Maimonides Institute of Biomedical Research (IMIBIC) Reina Sofia University HospitalSpain Consortium for Biomedical Research in Frailty & Healthy Ageing CIBERFESCarlos III Institute of HealthSpain

Cocoa is the main component of chocolate.It is widely accepted that cocoa quality largely depends on the processing,especially the fermentation step.Traditionally,fermentation takes place spontaneously by the endogenous microbiota;however,the process can lead to poor quality and heterogeneity of the final product.In this study,we evaluated the influence of the starter culture on the profile of volatiles during fermentation of commercial volumes of Mexican cocoa.Volatiles were also analyzed in post-fermented cocoa samples obtained after drying,roasting,and conching.Our results revealed a most desirable volatile profile in cocoa fermented with starter culture,mainly due to the higher relative content of alcohols(40%)and aldehydes(3.5%),but also due to a lower acidity(dehydes<0.5%).Additionally,it is remarkable,the higher content of pyrazines in the inoculated samples after processing.

关键词： Cocoa beans Starter culture Cocoa fermentation Postfermentation Volatile compounds Mass spectrometry

The Classical Limit of the Quantum Kepler Problem

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Journal of Modern Physics 2013年第6期4卷 818-822页

作者： A. Martín-Ruiz J. Bernal Alejandro Frank Adrián Carbajal-Dominguez Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. México Instituto de Ciencias Nucleares Universidad Nacional Autónoma de México México D.F. México Centro de Ciencias de la Complejidad Universidad Nacional Autónoma de México México D.F. México universidad juárez autónoma de tabasco División Académica de Ciencias Básicas Cunduacán México

The classical limit of the quantum mechanical Kepler problem is derived by using a simple mathematical procedure recently proposed. The method is based both on Bohr’s correspondence principle and the local averages of the quantum probability distribution. We illustrate in a clear fashion the difference between Planck’s limit and Bohr’s correspondence principle. We discuss the confinement effect in macroscopic systems.

关键词： Kepler Problem Classical Limits