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Psychology: an approach from theory
No full textEl artículo describe la condición científica de la Psicología desde un acercamiento teórico. Se utiliza como método el cualitativo, enfoque pospositivista, paradigma constructivista, técnica la hermenéutica, y para el análisis de los resultados la interpretación. La Psicología pasó de ser una variable difícil de explicar, a una ciencia independiente, capaz de estudiar la mente y conducta humana, prevaleciendo en ella los registros observables, sus objetivos y técnicas, lo que repercute en su confiabilidad y validación científicaThe article describes the scientific condition of Psychology from atheoretical approach. The qualitative method, the post-positivist approach, the constructivist paradigm, the hermeneutics technique, and interpretation for the analysis of the results are used. Psychology went from being a difficult variable to explain, to an independent science, capable of studying the human mind and behavior, prevailing in it observable records, its objectives and techniques, which affects its reliability and scientific validation
A new route of valorization of petrochemical wastewater: recovery of 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethyl benzyl)–1,3,5-triazine-2,4,6-(1h,3h,5h)-trione (cyanox 1790) and its subsequent application in a PP matrix to improve its thermal stability
No full textThe various chemicals in industrial wastewater can be beneficial for improving its circularity. If extraction methods are used to capture valuable components from the wastewater and then recirculate them throughout the process, the potential of the wastewater can be fully exploited. In this study, wastewater produced after the polypropylene deodorization process was evaluated. These waters remove the remains of the additives used to create the resin. With this recovery, contamination of the water bodies is avoided, and the polymer production process becomes more circular. The phenolic component was recovered by solid-phase extraction and HPLC, with a recovery rate of over 95%. FTIR and DSC were used to evaluate the purity of the extracted compound. After the phenolic compound was applied to the resin and its thermal stability was analyzed via TGA, the compound’s efficacy was finally determined. The results showed that the recovered additive improves the thermal qualities of the material
Factors that explain, mediate and moderate business failure: review of publications indexed in Scopus (2015-2022)
No full textExplicar el fracaso empresarial es un tema que ha llamado la atención de investigadores. Sin embargo, predecir cuándo una empresa fracasará, es una limitación que aún se encuentra lejos de ser resuelta. Por este motivo, el objetivo del artículo es caracterizar las variables que explican, moderan y median el fracaso empresarial. Esto se logra a través de una rigurosa revisión de artículos publicados en la base de datos Scopus. Se verificó que el descriptor de búsqueda “Business failure” arrojó resultados más coherentes con el objetivo del estudio. Se limitaron los resultados por las áreas temáticas “Business management and accounting” y “Economics, econometrics and finance” y al periodo comprendido entre los años 2015 y 2022; sin delimitar el país e idioma. La investigación sigue un enfoque cualitativo, método inductivo, de alcance descriptivo y diseño longitudinal. Los principales resultados destacan una tendencia a considerar como variables explicativas, moderadoras y mediadoras del fracaso empresarial, aspectos concernientes a la administración y, en segundo lugar, las relacionadas con el entorno. Además, se evidencia el uso de técnicas de inteligencia artificial que tratan de predecirlo. Se concluye, que de la relación administración-entorno, surgen nuevas fuentes de variables que pueden explicar, moderar y mediar el fracaso empresarial.Explaining business failure is a topic that has drawn the attention of researchers. However, predicting when a company will fail is a limitation that is still far from being resolved. For this reason, the article aims to characterize the variables that explain, moderate, and mediate business failure. This is achieved through a rigorous review of articles published in the Scopus database. It was verified that the search descriptor “Business failure” yielded more consistent results with the study’s objective. The results were limited by the subject areas “Business management and accounting” and “Economics, econometrics and finance” and to the period between 2015 and 2022; without delimiting the country and language. The research follows a qualitative approach, inductive method, descriptive scope, and longitudinal design. The main results highlight a tendency to consider aspects of administration and environment as explanatory, moderating, and mediating variables of business failure. In addition, the use of artificial intelligence techniques that try to predict it is evident. It is concluded that from the administration-environment relationship, new sources of variables arise that can explain, moderate, and mediate business failure
Theoretical–experimental study of the action of trace amounts of formaldehyde, propionaldehyde, and butyraldehyde as inhibitors of the ziegler–natta catalyst and the synthesis of an ethylene–propylene copolymer
No full textThe copolymer synthesis process can be affected by failures in the production process or by contaminating compounds such as ketones, thiols, and gases, among others. These impurities act as an inhibiting agent of the Ziegler–Natta (ZN) catalyst affecting its productivity and disturbing the polymerization reaction. In this work, the effect of formaldehyde, propionaldehyde, and butyraldehyde on the ZN catalyst and the way in which it affects the final properties of the ethylene-propylene copolymer is presented by analyzing 30 samples with different concentrations of the mentioned aldehydes along with three control samples. It was determined that the presence of formaldehyde 26 ppm, propionaldehyde 65.2 ppm, and butyraldehyde 181.2 ppm considerably affect the productivity levels of the ZN catalyst; this effect increases as the concentration of aldehydes is higher in the process; likewise, these impurities affect the properties of the final product, such as the fluidity index (MFI), thermogravimetric analysis (TGA), bending, tension, and impact, which leads to a polymer with low-quality standards and less resistance to breakage. The computational analysis showed that the complexes formed by formaldehyde, propionaldehyde, and butyraldehyde with the active center of the catalyst are more stable than those obtained by the ethylene-Ti and propylene-Ti complexes, presenting values of −40.5, −47.22, −47.5, −5.2 and −1.3 kcal mol−1 respectivel
Wood waste-based functionalized natural hydrochar for the effective removal of Ce(III) ions from aqueous solution
No full textIn this study, a sustainable and easily prepared hydrochar from wood waste was studied to adsorb and recover the rare earth element cerium (Ce(III)) from an aqueous solution. The results revealed that the hydrochar contains several surface functional groups (e.g., C–O, C = O, OH, COOH), which largely influenced its adsorption capacity. The effect of pH strongly influenced the Ce(III) removal, achieving its maximum removal efficiency at pH 6.0 and very low adsorption capacity under an acidic solution. The hydrochar proved to be highly efficient in Ce(III) adsorption reaching a maximum adsorption capacity of 327.9 mg g−1 at 298 K. The kinetic and equilibrium process were better fitted by the general order and Liu isotherm model, respectively. Possible mechanisms of Ce(III) adsorption on the hydrochar structure could be explained by electrostatic interactions and chelation between surface functional groups and the Ce(III). Furthermore, the hydrochar exhibited an excellent regeneration capacity upon using 1 mol L−1 of sulfuric acid (H2SO4) as eluent, and it was reused for three cycles without losing its adsorption performance. This research proposes a sustainable approach for developing an efficient adsorbent with excellent physicochemical and adsorption properties for Ce(III) removal
Biocatalysis: an eco-friendly scenario for the manufacturing of APIs
No full textNowadays, the worldwide demand for Active Pharmaceutical Ingredients (APIs) requires novel, cost-effective, safe, and environmentally friendly synthetic processes. Given this scenario, biocatalysis has started to take an ever-growing impact on industrial chemical processes [1,2]. The application of enzymes to catalyze industrial reactions has the potential to make chemical processes less contaminant and more sustainable, in accordance with the concept and principles of Green Chemistry [3]. Moreover, biocatalysis offers additional advantages, such as the possibility to perform one-pot reactions, a higher region- and stereo-selectivity, or the absence of intermediates that require tedious purification steps, which make enzyme-mediated processes a powerful ally for a successful industrial implementation of a process
Guías de laboratorio de lenguaje, cognición y pensamiento
No full textEl compendio de guías de laboratorio de lenguaje, cognición y pensamiento enfocadas a la psicología, incluyen prácticas que les permiten a los estudiantes fortalecer habilidades al aplicar conceptos de la asignatura en un ambiente de laboratorio. Esta guía articula experiencias fundamentales que incluyen normativa de seguridad aplicable, recursos a utilizar, procedimientos, cálculos y un cuestionario de análisis. Con ello, los estudiantes podrán consolidar los conocimientos teórico-prácticos al aplicar conceptos de las temáticas de la asignatura de lenguaje, cognición y pensamiento.Relación entre Pensamiento y Lenguaje 3 -- 1. Introducción 4 -- 2. Conceptos Básicos 4 -- 3. Elemento de Competencia 5 -- 4. Logro 5 -- 5. Escenario de Aprendizaje 5 -- 6. Método de Implementación de la Práctica 7 Recursos 7 Procedimiento 7 Resultado de la Práctica 8 -- 7. Bibliografía
Energy evaluation of pumping systems in a clean water plant: a case study
No full textThis paper presents a methodology based on the ISO-50001 standard to assess the energy impact of replacing standard-efficiency motors with high-efficiency motors driven by variable speed drives in an industrial pumping system. The methodology includes the inspection and installation of the new technology, measurements, data processing, and analysis of the results. In addition, an energy efficiency indicator, an energy baseline, and a Pareto diagram are used, while the harmonics generated by new technologies are evaluated. The contribution of the methodology is that it allows for a comprehensive energy diagnosis using easily measurable data like electricity consumption and water flow, replacing the measurement of the motor's mechanical power in industrial conditions, which is a current challenge. The methodology applied in the case study showed that the technological changes saved 36% of energy and that the variable speed drives increased current harmonics by 10%
Assessment for learning: Tensions and challenges in the framework of learning outcomes energized through teaching practice - case of Universidad de la Costa-UNICOSTA
No full textThis work is based on the systematization of academic processes at Universidad de la Costa, making a valuable contribution to pedagogical reflection on the significance of evaluation as a process that ensures learning through classroom-based support. The objective is to describe the tensions, challenges, and achievements among the individuals who drive the evaluation process. While all elements of learning assessment are important, formative assessment has garnered significant interest. It involves teachers providing continuous feedback to students, enabling them to be aware of their learning progress. This empowers students to identify their current situation, needs, and the necessary actions to develop their general and specific skills. To achieve this, a comprehensive integration of actions and transformations was undertaken, involving all institutional stakeholders involved in learning assessment. This led to teachers strengthening their diagnostic, formative, and summative functions, recognizing the fundamental roles of teachers and students in the learning process. This process allowed for the identification of uncertainties and challenges in the culture of learning assessment, and facilitated institutional actions aimed at enhancing assessment practices through the analysis of learning outcomes. These outcomes serve as a basis for continuous improvement
Identifying, quantifying, and recovering a sorbitol-type petrochemical additive in industrial wastewater and its subsequent application in a polymeric matrix as a nucleating agent
No full textCurrently, polypropylene (PP) is highlighted using sorbitol-based clarifying agents since these agents are high quality, low cost, and work as a barrier against moisture, which makes PP ideal for packaging food, beverages, and medical products, among others. The use of analytical methods capable of recovering these additives in wastewater streams and then reusing them in the PP clarification stage represents an innovative methodology that makes a substantial contribution to the circular economy of the PP production industry. In this study, a method of extraction and recovery of the Millad NX 8000 was developed. The additive was recovered using GC-MS and extracted with an activated carbon column plus glass fiber, using an injection molded sample, obtaining a recovery rate greater than 96%. TGA, DSC, and FTIR were used to evaluate the recovered additive’s glass transitions and purity. The thermal degradation of the recovered additive was found to be between 340 and 420 °C, with a melting temperature of 246 °C, adopting the same behavior as the pure additive. In FTIR, the characteristic absorption peak of Millad NX 8000 was observed at 1073 cm−1, which indicates the purity of the extracted compound. Therefore, this work develops a new additive recovery methodology with high purity to regulate the crystallization behavior and of PP