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Copper Oxide Inked with Dye Obtained from the Lactarius Indigo Fungus for Energy Production

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Journal of Materials Science and Chemical Engineering 2022年第11期10卷 36-51页

作者： Abigail Bautista Castañeda Maria Guadalupe Montes De Oca Dulce Yolotzin Medina Velazquez Jorge Iván Aldana González Pedro Adrian Martinez Montolla joan reyes miranda Miguel Angel Barron Universidad Autónoma Metropolitana Departamento de Materiales Ciencias Básicas e Ingeniería Reynosa Tamaulipas México Instituto Politécnico Nacional ESIQIE UPALM S/N Col. Mexico City México

The results obtained from the characterization of a copper deposit on indium doped tin oxide (ITO), inked with natural dye extracted from the Lactarius indigo fungus, for use in Gratzel type solar cells are reported. An electrolyte composed of 0.1 M HNO3 and 0.5 M CuSO4 was used, this solution was prepared for copper deposits on the ITO. Cyclic voltammetry was performed at different scan rates to obtain the reduction zone for deposition between potentials of ?100 to ?500 mV. The dye was obtained from the indigo Lactarius fungus from maceration, once the inked deposits were obtained, characterizations were performed, the initial test was to obtain the Ultraviolet-Visible (UV-visible) of the pure dye, and later the same test was performed on the inked oxide. Electrochemical Impedance Spectroscopy (EIS) was performed on the samples, as well as Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM), to characterize the material properties for its application.

关键词： Copper Oxide Ink Dye Energy Production Indigo Milk Mushroom

Mathematical Modelling of Einstein’s Rate Equations for Zinc Phosphate Glass with Er3+-Yb3+

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Open Journal of Applied Sciences 2021年第9期11卷 1038-1045页

作者： Frida Lissete Flores Rivera Grethell Georgina Pérez-Sánchez Miguel Angel Barron-Meza joan reyes miranda Dulce Yolotzin Medina Velázquez Division of Basic Science and Engineering Universidad Autónoma Metropolitana México City México

There is a constant growth in the demand of data information transmission capacity, that is, more and more people send data, voice, video signals, among others, through communications networks. Due to the above there is great interest in improving network devices, such as optical amplifiers, which must cover a large bandwidth and generate greater gain than those currently available. For this reason in this work a computational simulation for a Quasi-system was carried out three energy levels of Erbium and Ytterbium varying their concentrations and proving that they are optimal candidates in a zinc phosphate matrix as this type of glass contains properties such as, high transparency, low melting point, high thermal stability, high gain density due to high solubility, low refractive index and low dispersion, which makes them optimal as signal amplifiers. The results confirm that by increasing the doping of the Erbium ion the gain of the amplifier decreases, contrary to the Ytterbium ion that by increasing the doping the gain of the amplifier increases.

关键词： Optical Telecommunications Rare Earths Doping Optical Amplifier Gain

Unsteady Non-Uniform Flow of Molten Metals in Rectangular Open Channels

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World Journal of Engineering and Technology 2022年第3期10卷 593-604页

作者： Miguel A. Barron joan reyes Dulce Y. miranda Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

In the metallurgical industries, it is very important to characterize the flow of molten metals in open channels given that they are transported through these devices to different plant sections. However, unlike the flow of water which has been studied since ancient times, the flow of molten metals in open channels has received little attention. The unsteady non-uniform flow of blast furnace molten pig iron in a rectangular open channel is analyzed in this work by numerical solution of the Saint-Venant equations. The influence of mesh size on the convergence of molten metal height is studied to determine the proper mesh and time step sizes. A sinusoidal inflow pulse is imposed at the entrance of the channel in order to analyze the propagation of the resulting wave. The influence of the angle of inclination of the channel and the roughness coefficient of the walls on the amplitude and the dynamic behavior of the height of the molten metal are analyzed. Phase portraits of the channel state variables are constructed and interpreted. Numerical simulations show that as the angle of inclination of the channel increases, the amplitude of the formed wave decreases. From 10 degrees onwards, the peak of the wave descends even below the initial height. On the other hand, the roughness coefficient affects the molten pig iron height profiles in an inverse way than the angle of inclination. The amplitude of the formed wave increases as the roughness coefficient increases.

关键词： Molten Metals Flow Non-Uniform Flow Open Channels Pig Iron Transport Saint-Venant Equations Sinusoidal Pulse Unsteady Flow

Luminescent Properties of the Mn2+Ion in Zinc Phosphate Glass

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Open Journal of Applied Sciences 2021年第11期11卷 1212-1217页

作者： Frida Lissete Flores Rivera Dulce Yolotzin Medina Velazquez Gabriela Verenice Arredondo Martínez Jorge Roberto Oliva Uc Carlos Eduardo Rodriguez Garcia Miguel Angel Barron-Meza joan reyes miranda Autonomus Metropolitan University Material Area Mexico City Mexico Potosino Institute for Scientific and Technological Research Advanced Materials Division San Luis Mexico Faculty of Physics-Mathematics Autonomous University of Coahuila Saltillo Mexico

In the development of new optoelectronic devices, mainly those related to solid state technology (SSL), the generation of luminescent materials with high intensity in visible region and low cost is of vital importance. For this reason, this work presents the luminescent properties of zinc phosphate glasses doped with the manganese ion 2+. The manganese ion offers a series of advantages with respect to rare earths, such as a more accessible cost and an intense emission in the red color that make it a great candidate for the generation of new optoelectronic devices. The methodology for the synthesis is presented in this work, as well as its luminescent properties, for concentrations of 2%, 10%, 13% and 15% atomic.

关键词： Luminescence Manganese Advanced Glasses

Blue-Red Tuning Emission of ZnO: Europium Quantum Dots with Different Excitation Wavelengths

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Open Journal of Applied Sciences 2018年第10期8卷 441-445页

作者： Primitivo Ortiz Maldonado Ana K. Chavez-Alvarado Francisco J. Rodríguez Gutierrez joan reyes miranda Dulce Y. Medina Velazquez Miguel A. Barron Elizabeth Garfias García Universidad Autónoma Intercultural de Sinaloa El Fuerte México División de Ciencias Básicas e Ingeniería Universidad Autónoma Metropolitana Reynosa Tamaulipas México

Optoelectronic applications require the development of new fluorescent and efficient luminescent materials, free of toxicity, low in cost, and easy to produce. In this way the synthesis of zinc-oxide (ZnO) quantum dots (QDs) has recently received special attention due to their good optical, electrical and chemical properties with low production costs and blue light emission. In this work ZnO QDs were successfully doped with europium in order to obtain a tunable emission luminescence from blue emission of ZnO to red emission of europium as a function of wavelength excitation. Results show an efficient blue to red tuning when the excitation wavelength was changed from 317 nm to 395 nm, respectively. This opens the possibility of having new optical devices to produce different color emission using the same material.

关键词： Chromaticity Diagram Emission Spectra Europium Luminescence Red-Blue Tuning ZnO Quantum Dots White Light

Uniform Flow of Molten Metals in Rectangular Open Channels

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World Journal of Engineering and Technology 2022年第3期10卷 518-526页

作者： Miguel A. Barron joan reyes Dulce Y. Medina Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

The flow of liquids in open channels has been studied since ancient Rome. However, the vast majority of published reports on flow in open channels are focused on the transport of drinking water and sewage disposal. The literature on the transport of molten metals in open channels is quite scarce. In this work, the uniform flow of pig iron and molten aluminum in rectangular open channels is studied. Specific energy curves are constructed and critical heights are analytically determined. The transition from subcritical to supercritical flow is analyzed as a function of the angle of inclination of the channel and the roughness of its walls. Manning’s equation is applied to the pig iron flow using data reported in the literature for molten aluminum. The need to correct the roughness coefficient for pig iron is observed in order to obtain results consistent with those previously reported.

关键词： Critical Height Froude Number Molten Metal Flow Open Channel Rectangular Channel Uniform Flow

A Straightforward Mathematical Model of Hot Metal Desulphurization

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Open Journal of Applied Sciences 2020年第6期10卷 318-327页

作者： Miguel A. Barron Dulce Y. Medina joan reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

A straightforward kinetic model for the hot metal desulphurization process is presented. The model contains some of the most important parameters and variables that govern the process. The inputs, outputs and parameters of a desulphurization program employed at industry are discussed. The model is able to cope with different injection policies of desulphurizers such as mono- injection, co-injection or multi-injection. When compared to the rotary impeller method, results of this model shows that the weight of lime consumed in the lance injection method is lesser than that consumed in the rotary impeller method for the same conditions of the hot metal charge.

关键词： Desulphurization Hot Metal Kinetic Model Lance Injection Rotary Impeller

Interaction between a Liquid Surface and an Impinging Gas Jet

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World Journal of Engineering and Technology 2021年第4期9卷 793-803页

作者： Miguel A. Barron Dulce Y. Medina joan reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

The water-air and Wood’s metal-air systems are modeled by means of Computational Fluid Dynamics to study the interaction between a liquid surface and an impinging air jet under the near field blowing conditions. The effect of the air jet velocity, the height of the injection lance, and the density of the liquid on the depth of the formed cavity is numerically studied. The CFD results of the cavity depth are compared with results previously reported by other authors. The emergence of the splashing phenomenon is predicted in terms of the critical velocity for each liquid-air system. Besides, the blowing number indicates that the drop generation rate is not significant for jet velocities below the critical velocity, and therefore neither the splashing is significant.

关键词： Cavity Depth CFD Impinging Gas Jet Lance Height Liquid-Gas Interaction Splashing

Analysis of Molten Metal Distribution in the Mold of a Horizontal Centrifugal Casting

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Open Journal of Applied Sciences 2020年第7期10卷 444-454页

作者： Miguel A. Barron Dulce Y. Medina joan reyes Departamento de Materiales Universidad Autonoma Metropolitana Azcapotzalco Mexico City Mexico

It is numerically studied the influence of the angular velocity, the molten metal viscosity, and the mold wall roughness on the molten metal distribution in the mold of a horizontal centrifugal casting process. The undesirable raining phenomenon sometimes arises in horizontal centrifugal casting. It occurs when the molten metal rains or falls from the top of the mold to the bottom while the mold is rotating. Using Computational Fluid Dynamics simulations, the conditions for the emergence of the raining phenomenon were explored in this work. For the system considered, angular velocities less than 77 rad/s cause the emergence of the raining phenomenon and accumulation of the molten metal in the lower part of the mold, whereas angular velocities greater than 77 rad/s produce a constant thickness of the molten metal and prevent raining.

关键词： Angular Velocity Centrifugal Casting Computational Fluid Dynamics Molten Metal Viscosity Wall Roughness