Laura Alicia Paniagua-Solar

The thermal and electrical phenomena that occur when a Peltier cell is subjected to temperature changes or a potential difference are known as the Seebeck and Peltier effects. Basically, the Peltier effect arises when the junction of two metals is subjected to a potential difference, and this generates a temperature difference. Similarly, if the metals are subjected to a temperature gradient, they generate an electrical potential differential. In particular, this work contemplates the characterization of a [Tin]Tellurium-Bismuth type Peltier cell subjected to temperature changes and electrical potential differences, where the Seebeck and Peltier coefficients, the work function, the efficiency of the Tellurium Bismuth materials in this conversion, and the basic parameters to characterize and understand the physical phenomena that occur in a cell of this type are determined.

Las personas que viven en zonas remotas o rurales en México tienen mayor dificultad para acceder a servicios básicos como son: agua, drenaje, energía eléctrica, estufas de gas LP entre otras. La implementación de tecnologías sustentables como lo son las estufas solares de acumulación ofrecen una alternativa para satisfacer las necesidades de cocción de alimentos, en este trabajo se presenta el diseño y simulación de dos estufas solares de acumulación una tipo convencional y prisma hexagonal; los resultados obtenidos muestran que la estufa hexagonal alcanza una temperatura de 30°C más alta comparada con la tradicional; asimismo, una eficiencia térmica y potencia de cocción mayor, lo que indica puede ser una alternativa para su implementación en zonas rurales donde el acceso a gas LP es nulo.

The applicability of clinoptilolite zeolites in controlling the emission of greenhouse gases (GHGs) such as CO₂, the most significant GHG, is investigated herein. In this research, Mexican natural zeolites (ATN) originating from an Atzinco deposit in the state of Puebla were used. Samples of modified clinoptilolite (ATH4, ATH3, ATH2 and ATH1) were obtained from the starting material by acid treatment of various intensities. Inverse gas chromatography was used to evaluate CO₂ adsorption in clinoptilolite, natural and chemically modified. Adsorption of CO₂ was investigated in the temperature range of 433–573 K, using a TCD detector, and He as a carrier gas. The experimental CO₂ adsorption data were processed by Freundlich and Langmuir equations. The degree of interaction between CO₂ and the dealuminated clinoptilolite samples was examined through the evaluation of the isosteric enthalpy of adsorption. This calculation was made by using the Clausius–Clapeyron equation, which established the following sequence: ATH1 > ATH2 > ATH4 > ATN > ATH3. The nanoporosity of these clinoptolite zeolites from new deposit in sedimentary rocks was studied through HRADS adsorption of N₂. Simultaneously, these zeolites were, respectively, characterized by XRD, EDS, and SEM. Micropores are described by the Dubinin–Asthakov distribution. Various adsorption mechanisms that occur in these nanoporous materials at different relative pressures can be visualized. The quantitative determination of starting mineral is described as: Ca-Clinoptilolite (88.76%) >> Montmorillonite (11.11%) >> quartz (0.13%). The Si/Al molar ratio after acid treatment is: ATH4 > ATH2 > ATN > ATH3 > ATH1. The Langmuir specific surface area (A_SL) varies as follows: ATN > ATH2 > ATH4 > ATH3 > ATH1. At the same time, the V_Σ values are as follows: ATN > ATH4 > ATH3 > ATH1 > ATH2.

Currently, technological alternatives are being sought for the substitution of fossil fuels for different reasons.One of the most relevant is the protection of the environment, to have an improvement in this aspect, the generation of energy through clean sources is sought. The PEMFC (Proton Exchange Membrane Fuel Cell) type fuel cells are an excellent alternative for the generation of clean energy because the residues of the fuel cell are mainly water and heat. In the present work, clinoptilolite zeolite was used to produce clean energy by a fuel cell using bioethanol as fuel. Zeolite showed promising results when used in combination with carbon and hydrogel as a solid electrolyte. The material was characterized by scanning electron microscopy and x-ray electron microscopy. The result showed a maximum power of 0.00589241 mW in a surface of 900 mm2 , which is considered a positive result. The catalyst is functional to produce energy by an electrooxidation reaction using bioethanol in a fuel cell at a low cost compared to traditionally platinum-based catalysts.