In the Amazon, Euterpe oleracea Mart. (açaí), is part of the identity of traditional communities, and the fruit is integrated into their everyday sociocultural dynamics. Hydrolysis and pyrolysis of residual biomass can be alternatives to yield sugars, ethanol, biochar and bio-oil. The açaí seeds subjected to oxidative pretreatment followed by acid hydrolysis increased cellulose to fermentable sugars (reaching 23.5%) and second-generation ethanol production (17.441 L t−1). Açaí oil (ca. 30%) was extracted using a Soxhlet apparatus (using hexane as solvent) and detected through gas chromatography coupled to mass spectrometry (GC-MS), where acids accounted for 82.43% of the total composition, while alcohols comprised only 13.15%. For pyrolysis, temperatures (500 and 550 °C), time (20 and 30 min), and activation temperature (750 and 800 °C) were evaluated, resulting in yields of ca. 22% for biochar and 30% for bio-oil. For the bio-oil, the main compounds detected by GC-MS were acids (16.3%), aldehydes (13.08%), amides (12.19%), alcohols (6.72%), and phenols (4.64%). The obtained biochar displayed surface area values of 553.7 m2 g−1 and 10% crystallinity, indicating its more amorphous nature. Amazon Mart açaí, , (açaí) communities dynamics biooil. biooil bio oil. bio-oil reaching 23.5% 235 23 5 secondgeneration second generation 17.441 17441 17 441 (17.44 t−1. t1 t t−1 . 1 t−1) ca (ca solvent GCMS, GCMS GC MS (GC-MS) 8243 82 43 82.43 composition 1315 13 15 13.15% 500 (50 55 °C, C °C 20 (2 3 min, min min) 750 (75 80 evaluated 22 biooil, oil, 16.3%, 163 16.3% 16 (16.3%) 13.08%, 1308 13.08% 08 (13.08%) 12.19%, 1219 12.19% 12 19 (12.19%) 6.72%, 672 6.72% 6 72 (6.72%) 4.64%. 464 4.64% 4 64 (4.64%) 5537 553 7 553. m g1 g g− 10 crystallinity nature (açaí 23.5 2 17.44 1744 44 (17.4 t− (GC-MS 824 8 82.4 131 13.15 50 (5 ( 75 (7 16.3 (16.3% 130 13.08 0 (13.08% 121 12.19 (12.19% 67 6.72 (6.72% 46 4.64 (4.64% 23. 17.4 174 (17. 82. 13.1 16. (16.3 13.0 (13.08 12.1 (12.19 6.7 (6.72 4.6 (4.64 17. (17 13. (16. (13.0 12. (12.1 6. (6.7 4. (4.6 (1 (16 (13. (12. (6. (4. (13 (12 (6 (4

ABSTRACT Proper waste management is a major worldwide concern; waste is disposed of directly into the environment, affecting water, soil and air quality. The development and production of green energy sources is strongly encouraged in modern society. The aim of this study, in accordance with Sustainable Development Goals (SDGs) 1, 2 and 7 of the 2030 Agenda of the UN, is to combine the correct disposal of animal waste with the generation of energy to mitigate the energy insecurity of families in an extremely vulnerable semi-arid region in the north-east of the country using biodigesters. To this end, a conceptual proposal was drawn up for a low-cost, easy-to-maintain and easy-to-use biodigester. A small-scale prototype was used to assess its operation by evaluating the main factors that affect biogas production (pH, temperature and the biomass properties: total solids, fixed solids, volatile solids, concentration of volatile fatty acids and C/N ratio). Evaluation of the test prototype gave satisfactory results that corroborate other studies and make it possible to propose an economically viable and efficient full-scale biodigester for biogas production. concern environment water quality society study SDGs (SDGs 1 203 UN semiarid semi arid northeast north east biodigesters end lowcost, lowcost low cost, cost low-cost easytomaintain easy maintain easytouse use smallscale small scale pH, pH (pH properties solids CN C N ratio. ratio . ratio) fullscale full 20

Abstract There are several characteristics that influence fire resistance of load-bearing masonries, wherein stand out the bricks compressive strength. Verification of wall systems fire behavior was conducted as prescribed by NBR 5628. This research aims to comparatively analyze fire resistance in real scale load-bearing walls, considering thermal insulation, structural stability, and airtightness. The thickness of the coating and laying mortar were standardized for all specimens just varying brick geometry and septs design in blocks of EST 60, 100, and 140 class. The obtained results show that the compressive strength of the bricks can induce both the structural stability of the constructive systems and its thermal insulation, being a typically critical characteristic for clay brick walls in a building fire. The sample with the highest compressive strength obtained the shortest local displacement, contributing to mitigate the generation of fissures in the system, enhancing the thermal insulation of the clay brick wall, and, thereby, its fire resistance. loadbearing load bearing masonries 5628 airtightness 60 100 14 class displacement system thereby 562 6 10 1 56 5

Resumo Diversas características influenciam a resistência ao fogo de sistema de parede em alvenaria estrutural, dentre as quais pode se incluir sua resistência à compressão. O comportamento desse sistema é validado experimentalmente conforme a norma NBR 5628. Esse estudo tem como objetivo analisar comparativamente a resistência ao fogo obtida através de ensaios em escala real em alvenaria estrutural, envolvendo as características de isolamento térmico, estanqueidade a passagem de gases e fumaça e estabilidade estrutural. Foram avaliados componentes com a mesma configuração em termos de revestimento e assentamento, assumindo como variável a resistência a compressão dos blocos, tendo sido considerados neste estudo blocos de classe EST 60, 100 e 140. Os resultados obtidos apontam que a resistência à compressão da alvenaria pode influenciar, além da estabilidade estrutural do sistema, também seu isolamento térmico, critério tipicamente crítico para alvenarias de blocos cerâmicos em situação de incêndio. A amostra de maior resistência à compressão apresentou menor deslocamento horizontal, contribuindo para mitigar a geração de fissuras, aumentando a oposição da alvenaria à passagem da temperatura ao longo de sua seção transversal e assim aumentar sua resistência ao fogo. 5628 térmico assentamento 60 10 140 influenciar incêndio horizontal fissuras 562 6 1 14 56 5

RESUMEN El fallo en una máquina eléctrica constituye un proceso inevitable debido a las solicitaciones térmicas, mecánicas, eléctricas y ambientales a las cuales se ven expuestas a lo largo de su vida útil, sin embargo, con una adecuada estrategia de mantenimiento, es posible evitar fallas imprevistas y lograr que la máquina alcance su vida útil. Antes de someter al activo a cualquier régimen de pruebas, es preciso evaluar su historial de operación, debido a que el indicio de cambio inusual en su condición, podría acusar una falla incipiente. Los fallos de mayor ocurrencia en los generadores sincrónicos de polos salientes son los de excentricidad, al estar directamente ligados a síntomas de daños en los cojinetes. La introducción de la componente fundamental de la corriente por el neutro del generador como variable de estado de diagnóstico de la excentricidad, constituye un aporte que optimiza el proceso de gestión del mantenimiento por su fácil manejo y su alto contenido de información.

ABSTRACT The failure of an electrical machine is an unavoidable process due to the thermal, mechanical, electrical and environmental stresses to which it is exposed throughout its useful life, however, with a proper maintenance strategy, it is possible to avoid unforeseen failures and ensure that the machine reaches its useful life. Before subjecting the asset to any testing regime, it is necessary to evaluate its operating history, because the indication of an unusual change in its condition could indicate an incipient failure. The most common failures in salient poles synchronous generators are eccentricity failures, as they are directly linked to symptoms of bearing damage. The introduction of the fundamental component of the current through the neutral of the generator as a state variable for the diagnosis of eccentricity is a contribution that optimizes the maintenance management process due to its easy handling and high content of information.

Abstract The study evaluates the generation and recovery capacity of methane at the Villavicencio Landfill in Colombia, using the LandGEM model. It shows a significant increase in methane generation, rising from about 1.5 million cubic meters in 2010 to over 8.5 million in 2020, indicating a growing urgency to implement effective mitigation measures. It was estimated that by the year 2042, the electrical energy production from methane could be 248.067 kW/day, capable of supplying about 43.705 homes monthly. Additionally, thermal energy generation would be 468.572 kWh/day, useful for industrial processes. Management scenarios were proposed, where, for example, operational optimization could increase electric production to 342.333 kW/day, benefiting more than 60.000 homes monthly. The conclusions highlight the direct correlation between the amount of waste and methane generation, and the significant potential for converting these emissions into energy, pointing towards regional energy self-sufficiency and sustainability. Methane recovery represents a valuable alternative to the dependence on fossil fuels and for the development of a circular economy.

Resumen El estudio evalúa la generación y capacidad de recuperación de metano en el Relleno Sanitario de Villavicencio, Colombia, mediante el modelo LandGEM. En donde se observa un aumento significativo en la generación de metano, pasando de alrededor de 1,5 millones de metros cúbicos en 2010 a más de 8,5 millones en 2020, lo que indica una creciente urgencia por implementar medidas de mitigación efectivas. Se estimó que, para el año 2042, la producción de energía eléctrica del metano podría ser de 248.067 kW/día, capaz de abastecer a unos 43.705 hogares mensualmente. Asimismo, se generaría energía térmica de 468.572 kWh/día, útil para procesos industriales. Se plantearon escenarios de gestión, donde, por ejemplo, la optimización operacional podría aumentar la producción eléctrica a 342.333 kW/día, beneficiando a más de 60.000 hogares mensualmente. Las conclusiones resaltan la correlación directa entre la cantidad de residuos y la generación de metano, y el significativo potencial de convertir estas emisiones en energía, apuntando hacia la autosuficiencia y sostenibilidad energética regional. El aprovechamiento del metano representa una alternativa valiosa frente a la dependencia de combustibles fósiles y para el desarrollo de una economía circular.

Abstract: This research proposes two models for the problem of short-term economic dispatch of electrical power systems through nonlinear programming (NLP). The problems raised will be resolved through the cost function of the classic economic dispatch where thermal and hydraulic generation plants will be considered to obtain the electrical power generated in each of the nodes. The proposed methodology will be used for a short-term period of 24 hours with different hourly demand, as it is a short-term dispatch, it focuses on the delivery of power that covers the designated demand in each schedule, so it will not consider a deficit cost or uncertainty in the variables in any of the cases. In the first instance, the model will be developed for a single node with cascade reservoirs, while the second case will be developed in the IEEE 14-bus system. The non-linear programming shows satisfactory results, complying with the operational restrictions implemented in the mathematical model, in addition, the participation of thermal generation is considerably reduced, which represents a lower cost. The first model of a node is validated through bibliography, obtaining an operating cost of $904,990. In the same way, complying with all the designated parameters, the second model obtains a total cost of $129,800, satisfying the total demand in both cases, subject to each of its restrictions.

Resumen: La presente investigación propone dos modelos al problema de despacho económico a corto plazo de los sistemas eléctricos de potencia por medio de la programación no lineal (PNL). Los problemas planteados serán resueltos mediante la función de costo del despacho económico clásico en donde se considerarán centrales de generación térmica e hidráulicas para obtención de la potencia eléctrica generada en cada uno de los nodos, la metodología propuesta será utilizada para un periodo a corto plazo de 24 horas con diferente demanda horaria, al ser un despacho a corto plazo este se enfoca en la entrega de potencia que cubra la demanda designada en cada horario, por lo que no considerará para ninguno de los casos un costo de déficit o incertidumbre en las variables. En primera instancia se desarrollará el modelo para un solo nodo con embalses en cascada, mientras que el segundo caso será desarrollado en el sistema de 14 buses de la IEEE. La programación no lineal muestra resultados satisfactorios cumpliendo con las restricciones operativas implementadas en el modelo matemático, además se reduce considerablemente la participación de generación térmica lo que representa menor costo, el primer modelo de un nodo es validado mediante bibliografía obteniendo un costo de operación de $904.990. De la misma forma, cumpliendo con todos los parámetros designados, el segundo modelo llega a obtener un costo total de $129.802,16 satisfaciendo el total de la demanda en ambos casos, sujeto a cada una de sus restricciones.

Abstract In the field of non-thermal food processing technologies, the application of cold plasma stands out for its rapid growth and broad prospects. Cold plasma is generated by applying energy to ionize a specific gas, producing highly reactive species such as reactive oxygen and nitrogen species, as well as ozone, ions, free radicals, and ultraviolet radiation. The most common configurations for generating cold plasma include dielectric barrier discharge and corona discharge. Key applications and effects include the destruction of biofilms, inactivation of microorganisms, decontamination of mycotoxins, degradation of pesticides, and modification of starches, among others. Proposed mechanisms of action range from chemical and molecular modifications to cellular lysis and genetic damage. This article provides an updated overview of the principles, generation, and applications of cold plasma technology in the food industry.

Resumen En el ámbito de las tecnologías no térmicas para el procesamiento de alimentos, la aplicación de plasma frío destaca por su rápido crecimiento y amplias proyecciones. El plasma frío se genera aplicando energía que ioniza un gas específico, lo que produce especies altamente reactivas como las reactivas de oxígeno y nitrógeno, además de ozono, iones, radicales libres y radiación ultravioleta. Las configuraciones más comunes para su generación incluyen la descarga de barrera dieléctrica y la descarga corona. Sus aplicaciones y efectos clave abarcan la destrucción de biofilms, inactivación de microorganismos, descontaminación de micotoxinas, degradación de pesticidas y modificación de almidones, entre otros. Los mecanismos de acción propuestos varían desde modificaciones químicas y moleculares hasta lisis celular y daño genético. Este artículo proporciona una visión general actualizada sobre los principios, generación y aplicaciones del plasma frío en la industria alimentaria.

RESUMEN Los concentradores solares lineales son una tecnología prometedora para la generación de energía térmica en el sector industrial. Estos sistemas pueden generar agua caliente o vapor, con temperaturas dentro de un amplio rango en función del proceso o demanda. En este trabajo se presenta el diseño, construcción, montaje y ensayo experimental de un concentrador Fresnel lineal de 1.44 m2 de superficie de espejos. El equipo fue capaz de elevar la temperatura del agua a valores superiores a los 70 ºC, para caudales inferiores a 1 l/min, desarrollando una potencia térmica de 2000 W. A su vez, el equipo ensayado desarrolló potencias superiores a los 5000 W para caudales elevados. Los resultados indican que los concentradores solares lineales son una tecnología viable para la generación de energía térmica en el sector industrial, y que la normalización o modularización en función de la capacidad de producción (l/m2dia) permite proponer a esta tecnología como alternativa a los sistemas de calentamiento pasivo (calefones) disponibles en el mercado.

ABSTRACT Linear solar concentrators are a promising technology for thermal energy generation in the industrial field. These systems can generate hot water or steam, with temperatures within a wide range depending on the process or demand. This work shows the design, construction, assembly, and experimental testing of a linear Fresnel concentrator with a collecting area of 1.44 m2. The device was able to raise the temperature of water to values above 70 °C for flow rates below 1 l/min, developing a thermal power of 2000 W. Additionally, the concentrator developed thermal power output above 5000 W for higher flow rates. The results indicate that linear solar concentrators are a viable technology for the generation of thermal energy in the industrial field, and that standardization based on production capacity (l/m2day) allows this technology to be proposed as an alternative to passive heating systems (water heaters) available on the market.

ABSTRACT The failure of an electrical machine is an inevitable process due to the thermal, mechanical, electrical and environmental stresses to which they are exposed throughout their useful life, however, with an adequate maintenance strategy, it is possible to avoid unforeseen failures and ensure that the machine fulfills its design functions, minimizing the risks of breakdown. The aim of this study is to evaluate a new variable of diagnostic state (VED) of the eccentricity of electric generator set in-service. As a result of the theoretical research carried out, it is determined that the fundamental component of the current through the neutral of the generator constitutes a variable that provides information on the degree of eccentricity of the asset, which can optimize the maintenance management process due to its easy handling and its high content of information on the condition of the rotating machine.

RESUMEN El fallo en una máquina eléctrica constituye un proceso inevitable debido a las solicitaciones térmicas, mecánicas, eléctricas y ambientales a las cuales se ven expuestas a lo largo de su vida útil, sin embargo, con una adecuada estrategia de mantenimiento, es posible evitar fallas imprevistas y lograr que la máquina cumpla sus funciones de diseños, minimizando los riesgos de avería. El presente trabajo pretende evaluar una nueva variable de estado de diagnóstico (VED) de la excentricidad de los generadores eléctricos en los grupos electrógenos en servicio. Como resultado de la investigación teórica realizada, se determina que la componente fundamental de la corriente por el neutro del generador constituye una variable que brinda información del grado de excentricidad del activo, lo cual puede optimizar el proceso de gestión del mantenimiento por su fácil manejo y su alto contenido de información sobre la condición de la máquina rotatoria.

In this review, we present the versatility of biomass and its derivatives obtained through thermal conversion processes (biochar and hydrochar) for applications in the development of electrochemical devices. This work highlights the generation of carbonaceous materials through pyrolysis and hydrothermal carbonization, in addition to proposing strategies to modify their physicochemical properties through activation methodologies to enhance their application as electrode materials. The processes of monitoring and degrading chemical species are discussed based on the diversity of electrodes that can be obtained with these bioderived coals, according to recent contributions available in the literature (2020-2023), which show the wide applicability of these materials in the field of electrochemistry. review biochar hydrochar devices carbonization coals 20202023, 20202023 2020 2023 , (2020-2023) electrochemistry 2020202 202 (2020-2023 202020 20 (2020-202 20202 2 (2020-20 (2020-2 (2020- (2020 (202 (20 (2 (

Abstract Energy sources, like hydro and wind power, present uncertain nature, characteristic that affects the electric power systems operation planning. Such factors require using methodologies capable to handle these uncertainties in interconnected hydro-thermal-wind power systems operation. This work proposes a computational model for the day-ahead unit commitment problem for interconnected hydro-thermal-wind power systems, considering the uncertainties related to wind power, water inflow, and energy demand, employing the Robust Optimization (RO). The optimization model consists in a three-level mixed integer linear programming problem, which is resolved using a two-stage decomposition approach, solved using the column-and-constraint generation algorithm. The model is validated using the 30 nodes IEEE and the 33 nodes Brazilian test system. The model proposed proved to have an operating cost proportional to the level of uncertainty and the methodology employed provides a preventive view of what may occur during the hydro-thermal-wind systems operation, allowing the central system operator to take certain actions in order to ensure reliable operating conditions. In addition, the model allowed the identification of important aspects related to computational costs, such as the verification that constraints that couple the problem in time and space significantly impact the simulation times of the problem. sources nature planning hydrothermalwind thermal dayahead day ahead inflow demand RO. RO . (RO) threelevel three twostage two stage approach columnandconstraint column constraint algorithm 3 conditions addition costs (RO

ABSTRACT A computer system was developed to determine the energy potential in pig’s enterprise with the purpose of using the renewable energy sources. For their design, the IDE NetBeans, version 8.1 was selected as environment. A program named RESCE (renewable energy sources, clean environment) was generated to create hybrid systems, in which a priority order is establish respect to the residuals treatment. In a second phase, an estimate was made to determine the potential of electric energy generation with other sources. The use of this system allow the maximum exploitation of all natural resources, without damage the environment and it is consistent with the concept of circular economy. It is concluded that the program, in addition of allowing the computerization of the use of renewable energy sources in pig enterprise, speeds up decisions-making.

RESUMEN Se desarrolló un sistema informático para la determinación del potencial energético en centros porcinos con el propósito de poder utilizar las fuentes renovables de energía. Para su diseño, se seleccionó como entorno el IDE NetBeans en su versión 8.1. Se generó un programa denominado FREAL (fuentes renovables de energía, ambiente limpio) para crear sistemas híbridos, en el cual se establece un orden de prioridad respecto al tratamiento de los residuales. En una segunda fase, se hizo una estimación para determinar el potencial de generación de energía eléctrica con otras fuentes. El uso de este sistema permite la explotación al máximo todos los recursos naturales, sin dañar al medio ambiente y es consecuente con el concepto de economía circular. Se concluye que el programa, además de que permite la informatización del uso de fuentes renovables de energía en los centros porcinos, agiliza la toma de decisiones.

ABSTRACT Improving natural ventilation during animal transportation is a promising approach for promoting animal well-being and reducing losses. The objective of this study was to evaluate in silico the efficiency of devices (airfoils and deflectors) used for cooling trailers during the transportation of pigs. Device performance was assessed using computational fluid dynamics (CFD) simulations and 3D modeling of the enthalpy profile of a trailer, and adaptive mesh generation was employed to construct a computational mesh. Turbulence treatments were performed using RANS model and k-ω SST models. The results revealed that compared with the conditions observed in commercial transportation, the use of an airfoil increased the airflow and reduced the enthalpy within the assessed trailer (-5.4%). Likewise, the use of deflectors resulted in a reduction in enthalpy (-3.04%), although their use led to a translocation of the thermal core to the front region of the upper floor of the trailer. Nevertheless, the use deflectors has been proven to be more efficient when combined with an airfoil. In conclusion, the results obtained from our CFD simulations provide evidence to indicate that it is possible to optimize ventilation within transport containers using aerodynamic devices. wellbeing well being losses airfoils pigs (CFD D kω k ω models 5.4%. 54 5.4% . 5 4 (-5.4%) Likewise 3.04%, 304 3.04% , 3 04 (-3.04%) Nevertheless conclusion 5.4 (-5.4% 30 3.04 0 (-3.04% 5. (-5.4 3.0 (-3.04 (-5. 3. (-3.0 (-5 (-3. (- (-3 (

Abstract The purpose of this study was to evaluate the cleanliness of Interstitial Free (IF) steels produced in a Ruhrstahl Heraeus (RH) vacuum degasser by determining the level of Al2O3 and Al-Ti-O inclusion types generated in three different process conditions: i) steel processed without thermal intervention; ii) steel processed with chemical heating and iii) steel processed with cooling by the scrap addition. The inclusion formation and remotion during these processes were analyzed. The influence of homogenization time was also studied. The content of inclusions was measured by a Scanning Electron Microscope (SEM) with an automated counting system denoted as Automated Steel Cleanliness Analysis Tool (ASCAT). This method can provide the size and composition of non-metallic compounds. The results have shown that the Ruhrstahl Heraeus (RH) process can improve the remotion efficiency of the inclusions, such as those larger than 2.5 mm, which is due to the molten steel circulating in RH vessel. For some inclusion types, higher concentrations were detected, but their size was smaller. For a heat where it was necessary to apply chemical heating using Al addition and O injection, there was detected a higher concentration of inclusions when compared with that cooled by scrap addition. In cooling heats, there is a strong generation of small and thin inclusions (<1.0 mm) that are very difficult to be removed from liquid steel. The size of the Al2O3(s) type is around eight times larger than Al-Ti type inclusions. IF (IF (RH AlO Al2O AlTiO Ti conditions i intervention ii iii analyzed studied SEM (SEM ASCAT. ASCAT . (ASCAT) nonmetallic non metallic compounds 25 2 5 2. mm vessel smaller injection heats <1.0 10 1 0 (<1. Al2O3s AlOs s Al2O3(s AlTi (ASCAT <1. (<1 <1 (< < (

Abstract Strong concerns over greenhouse gas emissions have required the construction of non-polluting energy sources such as wind farms and photovoltaic plants. This need, combined with recent technological developments, has enabled the global installed capacity of wind farms in particular to grow from a negligible level in 2001 to more than 900 GW in 2023. However, due to the high variability of wind, this energy source is non-dispatchable, i.e., it cannot be controlled by operators to meet demand in a short amount of time. This problem can be mitigated by the allocation of energy storage systems (ESSs) to appropriate buses. This paper proposes an optimization model for the allocation of large-scale ESSs using a genetic algorithm (GA) and a linear multi-period optimal power flow (LMOPF). The GA enables the best allocation of the ESS to buses, their dimensions (i.e., selection of the power and energy of the ESS) and four types of technology. The LMOPF is used to perform system planning for a horizon of np periods, and to carry out the generation dispatch of a high voltage hydro-thermal-wind system and the charging and discharging processes of the ESS allocated by the GA. Due to the large size of the system and the complexity of resolution, a single-phase network model was chosen, and reactive power was disregarded. The model was tested using a system in the south of Brazil. The results showed that the optimal allocation of ESSs allowed for a hydroelectric energy time-shift, reducing the daily costs of operation. nonpolluting non polluting plants need developments 200 90 2023 However nondispatchable, nondispatchable dispatchable, dispatchable non-dispatchable ie i e i.e. time (ESSs buses largescale scale (GA multiperiod multi period LMOPF. . (LMOPF) (i.e. technology periods hydrothermalwind hydro thermal resolution singlephase single phase chosen disregarded Brazil timeshift, timeshift shift, shift time-shift operation 20 9 202 i.e (LMOPF (i.e 2