Departamento De Ingeniería Mecánica Agrícola

The main aim of this study was to characterize cooked bagasse fi bers from Agave angustifolia Haw. The fi bers were characterized using scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, X-ray Diffrac-tion and chemical analysis. The tensile strength was also tested using fi bers with a uniform length (30 mm). The fi bers were light brown in color, with a mean diameter and length of 501 μm and 144 mm, respectively. Scanning electron microscopy images revealed elliptically shaped cells with varying lumen size. Holocellulose content was approximately 82.12 %, and total lignin content was approximately 20.69 %. Due to the crystallinity and lignin content, the fi bers proved to be thermo-stable until 220 °C. The mean values of tensile strength, Young's modulus, % strain (ε), and ultimate tensile strength were determined via mechanical tests. The results are comparable to those of other common lignocellulosic fi bers, confi rming their potential use as a reinforcing element in a polymer matrix to form a new biodegradable composite. Resumen: El objetivo principal de este estudio fue caracterizar las fi bras de bagazo cocido de Agave angustifolia Haw. Las fi bras fueron caracterizadas a través de microscopia electrónica de barrido, calorimetría diferencial de barrido, análisis termogravimétri-cos, difracción de rayos X y análisis químico. También se realizaron pruebas de resistencia a la tracción usando fi bras de longitud constante (30 mm). Las fi bras presentaron un color marrón claro, con diámetro medio de 501 μm y longitud media de 144 mm. Las imágenes del microscopio electrónico de barrido mostraron células de forma elíptica con diferente tamaño de lumen. El con-tenido de holocelulosa fue alrededor de 82.12 % y el contenido total de lignina de aproximadamente 20.69 %. La fi bra resultó ser térmicamente estable hasta 220 °C debido a la cristalinidad y el contenido de lignina. El esfuerzo de tensión, el módulo de Young, el porcentaje de deformación (ε) y el esfuerzo último de tensión fueron obtenidos de las pruebas mecánicas. Los resultados son comparables a los de otras fi bras lignocelulósicas comunes, lo cual confi rma que estas fi bras tienen potencial como refuerzo en una matriz polimérica para formar un nuevo compuesto biodegradable. Palabras clave: análisis térmico, composición química, cristalinidad, morfología, pruebas mecánicas.

A neural network and a genetic algorithm were used in a hybrid method to get the optimal design parameters of an Agave angustifolia Haw. green leaf shredder. First, a prototype of an experimental machine was built using the design parameters recommended by the literature and calculated using linear equations. Then, the shredder prototype was subjected to experiments. The defibration data with different blade adjustments were obtained with experimental values. The data was configured and trained with an artificial neural network to establish a correlation between the defibration quality and the design parameters. The multi-objective optimization method based on genetic algorithms determined the optimal design parameters of the shredder's functional mechanical elements. The best point was obtained from the least number of broken fibers (2.83%) and the most waste (73.15%). The method used proved suitable to optim ize the design parameters; this was based on actual data obtained by experiments performed with the prototype and then modeled through artificial intelligence methods such as neural networks to determine an optimal solution using evolutionary genetic algorithm methods.

El suelo está compuesto por minerales, materia orgánica, diminutos organismos vegetales y animales, aire y agua. Las plantas y animales que crecen y mueren dentro y sobre el suelo son descompuestos por los microorganismos, transformados en materia orgánica y mezclados con el suelo.

The introduction of information technologies and communication technologies (ICT) in higher education has been a constant that has increased the technological empowerment of universities and adapt these tools to educational programs. In Chapingo Autonomous University (ChAU) seeks to introduce and develop the use of ICT in different Curriculum, both at the undergraduate level, as the graduate and high school level, plus administrative management. In this paper the results obtained on the use of ICT in the program of Agricultural Mechanical Engineering (AME) is exposed.The present study is a quantitative research descriptive, A poll of 57 students graduated with 23 closed reagents that measure both the frequency of use of ICT in the educational program, as some elements of quality through variables applied “always”, “usually”, “sometimes”, “rarely” or “never” to be processed with a Likert scaling with values of 5 to 1. The results reflect the achievements and shortcomings in the use o...