Resumo A produção de tintas utilizando resíduos de beneficiamento de granito e mármore é uma nova alternativa para contribuir com o desenvolvimento sustentável na construção civil. Entretanto, a carência de estudos sobre a composição e o desempenho dessas tintas inviabiliza a disseminação desse novo material de construção. Logo, este estudo tem como objetivo investigar a composição dessas tintas utilizando ferramentas estatísticas para obter produtos com desempenho compatível com regulamentações técnicas e tintas comerciais. As formulações de tintas foram definidas através de um planejamento de misturas quaternárias. O teor de sólidos, pH, viscosidade, poder de cobertura e resistência à abrasão foram determinados para todas as amostras. As tintas produzidas com resíduos de granito apresentaram melhor poder de cobertura e resistência à abrasão, pois o resíduo de granito apresenta granulometria mais fina, além de ser predominantemente composto por sílica. Por fim, as tintas produzidas neste estudo e as tintas comerciais apresentaram comportamento semelhante, o que corrobora com o aproveitamento do resíduo do processamento de rochas ornamentais na produção de tintas. civil Entretanto Logo quaternárias sólidos pH viscosidade amostras fina sílica fim semelhante

Abstract The production of paints using waste from granite and marble processing is a new alternative to contribute to sustainable development in civil construction. However, the lack of studies on the composition and performance of these paints makes the dissemination of this new construction material unfeasible. Therefore, this study aims to investigate the composition of these paints using statistical tools to obtain products with performance compatible with technical regulations and commercial paints. The paint formulations were defined through a quaternary mixture planning. The solids content, pH, viscosity, hiding power, and abrasion resistance were determined for all samples. The paints produced with granite waste showed better hiding power and abrasion resistance, as granite waste has a finer granulometry, in addition to being predominantly composed of silica. Finally, the paints produced in this study and the commercial paints showed similar behavior, which supports the use of waste from the processing of ornamental rocks in paint production. However unfeasible Therefore planning content pH viscosity samples granulometry silica Finally behavior

Abstract Rural roads serve as pivotal conduits for the transportation of harvested crops to distribution hubs in Guarapuava-PR, a national agricultural focal point. This study evaluated the impact of incorporating brick kilns ashes(BKA) into the lateritic soil of an unpaved roadway. Mixtures of soil and BKA with three distinct granulometries were formulated, featuring substitution rates of 25%, 50%, and 75% ash relative to the total mixture mass,characterized in terms of: particle size distribution, liquid limit (LL), plastic limit (PL), and the optimum point on the compaction curve under modified energy conditions (optimal moisture content and maximum dry bulk density). Results revealed that BKA inclusion led to increases in LL, PL, OMC, CBR, alongside a reduction of MDD and expansion for the majority of mixtures, particularly within granulometry C1 at a 25% content. Finer ashes exhibited prominence in ISC and expansion outcomes. Substitutions of 75% BKA detrimentally affected geotechnical properties; however, granulometric stabilization with BKA proved feasible, particularly in soil-C2 mixtures designated for use as a sub-base. These mixtures met recommended LL and PL parameters, providing effective waste mitigation and presenting an alternative for soil improvement in pavement applications. GuarapuavaPR, GuarapuavaPR Guarapuava PR, PR Guarapuava-PR ashesBKA ashes(BKA roadway formulated 25 50 50% 75 masscharacterized mass characterized , (LL) (PL) optimal density. density . density) OMC CBR C outcomes properties however feasible soilC2 soilC C2 soil-C subbase. subbase sub base. base sub-base parameters applications 2 5 7 (LL (PL

Resumo Estradas vicinais são muito utilizadas para o escoamento da safra da área da colheita até os centros de distribuição na cidade de Guarapuava-PR, referência nacional no setor agrícola. Esta pesquisa avaliou o efeito da adição de cinzas de fornos de olarias (CFO) ao solo laterítico de uma estrada não pavimentada. Foram produzidas misturas de solo e CFO de três diferentes granulometrias, nos teores de substituição de 25%, 50% e 75%, de cinza em relação à massa total da mistura, caracterizadas quanto à:granulometria, limite de liquidez (LL), limite de plasticidade (LP) e ponto ótimo da curva de compactação sob energia modificada (umidade ótima (wot) e peso específico aparente seco máximo (ρdmáx)). Os resultados obtidos mostraram que a adição da CFO foi responsável por aumentos nos parâmetros LL, LP, wot, ISC, bem como pela redução do ρdmáx e da expansão da maioria das misturas, principalmente para a granulometria C1, no teor de 25%. Cinzas mais finas destacaram-se nos resultados de ISC e expansão. Substituições de 75% de CFO prejudicaram as propriedades geotécnicas, mas a estabilização granulométrica com CFO revelou-se viável, especialmente em misturas solo-C2 para utilização como sub-base, atendendo aos parâmetros recomendados de LL e LP, proporcionando mitigação de resíduos e uma alternativa para melhoramento de solos para pavimentação. GuarapuavaPR, GuarapuavaPR Guarapuava PR, PR Guarapuava-PR agrícola (CFO pavimentada granulometrias 25 25% 50 75 mistura àgranulometria, àgranulometria granulometria, à:granulometria , (LL) LP (LP umidade wot (wot ρdmáx. . (ρdmáx)) C1 C destacaramse destacaram se geotécnicas revelouse revelou viável soloC2 soloC C2 solo-C subbase, subbase sub base, base sub-base pavimentação 2 5 7 (LL (ρdmáx) (ρdmáx

ABSTRACT Considering previous studies on the potential use of vinasse in the agricultural sector, this study seeks to design a feed for broilers in three presentations according to the stages of the animal’s feeding program (start 1-14, growth 15-30 and end 31-42 days) that includes vinasse in the formulation. To this end, soybeans were considered as a source of protein, a diet with metabolizable energy between 12,351.06 and 14,025.78 kJ∙kg-1. The granulometry was determined according to the broiler management manuals, and the feed manufacturing process was specified in a block diagram and a flow diagram; in the same way, a test protocol for the use of the feed formulated in a sample of broilers of the Cobb breed. This research suggests that using vinasse in feed formulations for broilers could provide significant benefits to the agricultural sector.

RESUMEN Considerando estudios previos sobre el potencial uso de la vinaza en el sector agropecuario, este estudio busca diseñar un alimento para pollos de engorde en tres presentaciones de acuerdo con las etapas del programa de alimentación del animal (inicio 1-14, crecimiento 15-30 y finalización 31-42 días) que incluya vinaza en la formulación. Para ello, se consideró el grano de soya como fuente de proteína, una dieta con energía metabolizable entre 12.351,06 a 14.025,78 kJ∙kg-1. Se determinó la granulometría de acuerdo con los manuales de manejo de pollos de engorde, y se especificó el proceso de fabricación del alimento en un diagrama de bloques y un diagrama de flujo; de igual forma se propone un protocolo de prueba para el uso del alimento formulado en una muestra de pollos de engorde de la raza Cobb. Esta investigación sugiere que el uso de la vinaza en las fórmulas de los beneficios para pollos de engorde podría aportar importantes beneficios al sector agrícola.

RESUMO Os sistemas de produção integrados surgiram como uma estratégia de produção sustentável na intensificação do uso da terra com impacto mínimo nas funções do ecossistema. Este estudo utilizou ferramentas de agricultura de precisão para investigar a variabilidade espacial de propriedades do solo e da vegetação em área de Integração Lavoura-Pecuária-Floresta (ILPF) e área de Integração Pecuária-Floresta (IPF) em São Carlos, SP, Brasil. Consequentemente, foram avaliados: (1) as propriedades físico-químicas do solo, (2) a resistividade elétrica, e (3) os atributos da cultura do Eucalyptus urograndis que compõem a área de estudo. As amostragens foram realizadas em (1) agosto de 2021 nas profundidades de 0-0,2 e 0,2-0,4 m; (2) outubro de 2021 nas profundidades de 0-0,5, 0-1,0 e 0-2,0 m; e (3) abril de 2021 e abril de 2022. Os resultados indicaram que os valores dos parâmetros de fertilidade do solo foram adequados ao desenvolvimento da cultura e apresentaram baixa variabilidade espacial. As análises de solo indicaram baixa acidez, altos teores de matéria orgânica, teores médios de fósforo, potássio e capacidade de troca catiônica e altos teores de cálcio, magnésio e saturação por base. Entretanto, foram observados locais com maior variabilidade espacial para cálcio, refletindo variabilidade na capacidade de troca catiônica e saturação por base. A granulometria e a resistividade elétrica do solo apresentaram baixa variabilidade espacial na camada superficial. Mesmo sem diferenças nas propriedades do solo, houve diferença de 15% no maior volume de madeira no sistema IPF em comparação ao ILPF. ecossistema LavouraPecuáriaFloresta Lavoura Pecuária Floresta ILPF (ILPF PecuáriaFloresta (IPF Carlos SP Brasil Consequentemente avaliados 1 (1 físicoquímicas físico químicas 2 (2 3 (3 202 00,2 002 0 0,2 0-0, 0,20,4 0204 0,4 4 0,2-0, m 00,5, 005 0,5, 5 0-0,5 01,0 010 1,0 0-1, 02,0 020 2,0 0-2, 2022 acidez orgânica fósforo cálcio base Entretanto superficial 15 ( 20 00 00, 02 0, 0-0 0,20, 04 0,2-0 00,5 05 0,5 01 01, 10 1, 0-1 02, 2, 0-2 0- 0,20 0,2-

ABSTRACT Integrated production systems have emerged as a sustainable production strategy in intensifying land use with minimal impact on ecosystem functions. This study used precision agriculture tools to investigate the spatial variability of soil and vegetation properties in an integrated crop-livestock-forestry (ICLF) and in an integrated livestock-forestry (ILF) area of São Carlos city, SP, Brazil. Consequently, the following were assessed: (1) the soil physicochemical properties, (2) the electrical resistivity, and (3) the attributes of the Eucalyptus urograndis crop comprising the study area. Samplings were performed in (1) August 2021 at depths of 0-0.2 and 0.2-0.4 m; (2) October 2021 at depths of 0-0.5, 0-1.0, and 0-2.0 m; and (3) April 2021 and April 2022. Results indicated that the values for soil fertility parameters were suitable for crop development and presented low spatial variability. Soil analyses indicated low acidity, high levels of organic matter, average cation exchange capacity, phosphorus and potassium contents, high base saturation, and calcium and magnesium levels. However, locations with greater spatial variability for calcium were observed, reflecting cation exchange capacity and base saturation variability. Soil granulometry and electrical resistivity had a low spatial variability at the surface layer. Even without differences in the soil properties, there was a difference of 15% in the larger wood volume in the ILF then ICLF system. functions croplivestockforestry livestock forestry (ICLF livestockforestry (ILF city SP Brazil Consequently assessed 1 (1 2 (2 3 (3 202 00.2 002 0 0.2 0-0. 0.20.4 0204 0.4 4 0.2-0. m 00.5, 005 0.5, 5 0-0.5 01.0, 010 1.0, 0-1.0 02.0 020 2.0 0-2. 2022 acidity matter contents However observed layer 15 system ( 20 00 00. 02 0. 0-0 0.20. 04 0.2-0 00.5 05 0.5 01 01.0 10 1.0 0-1. 02. 2. 0-2 0- 0.20 0.2- 01. 1. 0-1

ABSTRACT The city of Bahía Blanca, located in the southwest of the province of Buenos Aires, has sustained for several decades a strong process of territorial expansion towards urban peripheral sectors. The use of land in the east and southeast of the city is currently manifested as an important element in the urban structure, sometimes without an adequate geotechnical study to know their response to the loads they can bear when used as physical support for engineering structures. With the aim of characterizing and classifying the soils of the outcropping and subsoil units of the sector, standardized in situ tests were carried out: resistance to penetration to estimate the compactness of the soil in its natural state and density of the soil in situ by the cone of sand method. In the laboratory, the granulometry determination method was applied by wet sieving and the Atterberg limits were determined. Based on the established parameters, the Unified Soil Classification System (USCS) was carried out. The preliminary studies carried out allowed us to define that, in the study area, the soils vary in depth from fine soils, clays of medium to high plasticity and silts of low plasticity, which grade to clayey sands / silty sands. The soils studied are mainly made up of: soils type CH and Cl on the surface that grade to SC and

RESUMEN La ciudad de Bahía Blanca, ubicada en el sudoeste de la provincia de Buenos Aires, sostiene desde hace varias décadas un fuerte proceso de expansión territorial hacia sectores periféricos urbanos. El uso de las tierras en el este y sudeste de la ciudad, se manifiesta actualmente como un elemento importante en la estructura urbana, en ocasiones sin un adecuado estudio geotécnico para estudiar su respuesta ante las cargas que puedan soportar cuando son utilizados como soporte físico de estructuras ingenieriles. Con el objetivo de caracterizar y clasificar los suelos de las unidades aflorantes y del subsuelo del sector, se realizaron ensayos normalizados in situ: resistencia a la penetración para estimar la compacidad del suelo en estado natural y densidad del suelo in situ por el método de cono de arena. En laboratorio se aplicó método de determinación de la granulometría mediante tamizado por vía húmeda y se determinaron los límites de Atterberg. En función a los parámetros establecidos se realizó la Clasificación Unificada de Suelos (Unified Soil Classification System, USCS). Los estudios preliminares realizados permitieron definir que, en el área de estudio los suelos varían en profundidad desde suelos finos, arcillas de plasticidad media a alta y limos de baja plasticidad, que gradan a arenas arcillosas / arenas limosas. Los suelos estudiados están constituidos principalmente por: suelos tipo CH y Cl en superficie que gradan a SC y SM.

RESUMEN El trabajo tuvo el propósito de caracterizar, desde el punto de vista químico, físico, granulométrico y mineralógico, un residuo industrial de hidróxido de calcio generado en el proceso de fabricación de acetileno. Las muestras se analizaron, primeramente, sin neutralizar; luego se realizó el mismo procedimiento, usando ácido sulfúrico a un 98 % de pureza. Para ambos casos, las temperaturas de calentamiento fueron de 500 oC y 900 oC. Para identificar las fases, los patrones de difracción fueron obtenidos usando fuente de radiación de cobre (CuKα, λ=1,5418 Å). Se determinó que el residual presenta CaO y MgO, lo que garantiza su pureza. Al calentarlo sin neutralizar a 500 oC se transforma el hidróxido de calcio y a los 900 oC hay pérdida del carbonato y del agua. En el residual, tanto sin tratamiento como neutralizado, está presente el hidróxido de calcio.

ABSTRACT The purpose of the work was to characterize, from the chemical, physical, granulometric and mineralogical point of view, an industrial residue of calcium hydroxide generated in the acetylene manufacturing process. Samples were first analyzed without neutralization; then the same procedure was performed using 98 % purity sulphuric acid. For both cases, the heating temperatures used were 500 °C and 900 °C. To identify the phases, diffraction patterns were obtained using copper radiation source (CuKα, λ = 1.5418 Å). It was determined that residual contains CaO and MgO, which guarantees its purity; heated at 500 °C, and without neutralizing, calcium hydroxide is transformed and there is loss of water and carbonate at 900 °C. In both untreated and neutralized waste, calcium hydroxide is present.

ABSTRACT Lamellae are a morphological feature of soils that can be observed visually, as horizontal layers or bands of varying quantity, thickness and depth in the soil profile. They are found frequently in soils from the central-west region of the province of Córdoba (Argentina). The objectives of this study are: 1) to identify the presence of lamellae in an area of the province of Córdoba, 2) to characterize their morphological aspects, and 3) to evaluate their effect on soil permeability. The existence of lamellae was confirmed in 195 profiles in the districts of Achiras, Río Cuarto, and Tegua (Córdoba, Argentina). In 54 profiles of Haplustolls, the quantity, thickness, shape, and depth of lamellae were registered. Samples were taken both from the pure lamella profile and from positions above and below it. Particle size distribution, organic matter, and saturated hydraulic conductivity were measured. The number of lamellae per profile ranges from one to four, and they are found at depths between 18 and 48 cm. They are mostly flat and continuous, and have an average thickness of 0.71 cm. In Haplustolls with loamy and sandy loam textures, an average 13% increase in lame llae clay content was observed, particularly in the fine colloid fraction (<0.001 mm). In contrast, an average 20% increase in organic matter content was observed in loamy soils. Saturated hydraulic conductivity was significantly reduced (30%-70%) where lamellae were present, altering soil permeability in sandy loam Haplustolls. This study confirms the presence of lamellae in Haplustolls in the central-west region of Córdoba and their effect on decreasing permeability in sandy loam soils.

RESUMEN El término “lamela” hace referencia a un rasgo morfológico de los suelos que se observa a simple vista en el perfil en forma de capas o bandas horizontales en cantidad, espesor y profundidades variables. Las mismas se encuentran en suelos del centro oeste de la provincia de Córdoba (Argentina). Los objetivos de este trabajo son: 1) registrar la presencia de lamelas en un área de la provincia de Córdoba, 2) caracterizar aspectos morfológicos y 3) evaluar el efecto de su presencia en la permeabilidad. Se comprobó la existencia de lamelas en 195 perfiles en las pedanías Achiras, Río Cuarto y Tegua (Córdoba, Argentina). En 54 perfiles de Haplustoles se registró la cantidad, espesor, forma y profundidad de lamelas. Se tomaron muestras en el perfil de lamela pura y en posiciones sobre y debajo de la misma. Se midió granulometría, materia orgánica y conductividad hidráulica saturada. La cantidad de lamelas por perfil oscila entre una a cuatro, con un espesor promedio de 0,71 cm, mayoritariamente de forma plana y continua y a profundidades entre 18 y 48 cm. En Haplustoles de textura franca y franca arenosa se comprobó un 13% promedio de ganancia en el contenido de arcilla de la lamela, particularmente de la fracción fina del coloide (< 0,001 mm). En contraste, el contenido de materia orgánica se incrementó un 20% promedio en los suelos de textura franca. Se comprobó también que la presencia de lamela en Haplustoles de textura franca arenosa, altera significativamente la permeabilidad del suelo, reduciendo la conductividad hidráulica saturada en la porción del horizonte que contiene la lamela, entre un 30 a un 70%. Este trabajo confirma la presencia de lamelas en Haplustoles del centro oeste de Córdoba y que provocan una disminución de la permeabilidad en suelos de textura franca arenosa.

Abstract We present the results of ongoing research on different clay sources at Antofagasta de la Sierra, evaluating their potential for pottery-making. It included outcrops mapping, sample collection, petrographic characterisation and experimental archaeology to characterise different clay sources in Antofagasta de la Sierra. The former allowed locating and analysing clay components and the experimentation defined clay behaviour during pottery-making, both before and after firing. Our analyses established different categories based on clay appropriateness for pottery making: highly appropriate, slightly appropriate and non-appropriate clays. According to experimentation, this difference takes place after firing, as many highly-plastic and plastic clays disaggregate and peel off generating slightly hard and disaggregated fabrics due to the presence of small to large carbonate inclusions. These results provide a reference for archaeological studies of fabrics including the composition, granulometry and abundance of inclusions naturally present in local clays. In addition, data from experimental archaeology such as malleability and plasticity, contraction rate, thermal resistance and strength will help define the processes involved in pottery manufacture.

Resumen Presentamos los primeros resultados de una investigación, cuyo objetivo principal fue estudiar las diferentes fuentes de arcilla de Antofagasta de la Sierra y evaluar su potencialidad para la manufactura cerámica. A partir del mapeo de los distintos afloramientos, la toma de muestras, el análisis petrográfico y la arqueología experimental, se caracterizaron distintas fuentes de arcilla de Antofagasta de la Sierra. Los primeros estudios posibilitaron ubicar y analizar los componentes de las mismas y la experimentación permitió evaluar los comportamientos de las arcillas en los procesos de manufactura cerámica, antes y después de la cocción. Los análisis implementados permitieron establecer diferentes categorías en función de su adecuación a la producción cerámica: arcillas muy aptas, arcillas poco aptas y arcillas no aptas. Los resultados de la experimentación permitieron observar que esta diferencia tiene lugar luego del proceso de cocción, en el cual muchas de las arcillas que presentan una buena a muy buena plasticidad y maleabilidad, se disgregan y descascaran dando como resultado cerámicas con poca dureza y una textura disgregable debido, en todos los casos, a la presencia de inclusiones de carbonatos de tamaños medianos a grandes. Esta información resultará útil a la hora de abordar el estudio de la tecnología cerámica, al proporcionar datos de referencia para el análisis arqueológico, como la composición, la granulometría y la abundancia de los clastos presentes en las arcillas locales.

Abstract Mining is the largest economic activity in Peru, contributing a considerable percentage of the country's Gross Domestic Product. However, the process of this activity evidences several socio-environmental conflicts. The generation of mining waste or expressed as mining tailings from the various processes is a latent threat that affects the spheres of sustainable development. The objective of this study was to propose the valorization of mining tailings as aggregates for road construction in the Andean region of Peru under a circular economy approach. Consequently, several analyses were carried out to evaluate its viability, such as the meteorological factor of precipitation, acidity or alkalinity, elements present in the sample, granulometry, California Bearing Ratio (CBR) and Marshall test. The results have shown that the proposal complies with the parameters established at the national level with a stability of 877.67 kg and a 25% utilization of mine tailings. In conclusion, the use of mine tailings as aggregates for construction is a viable proposal for road construction under a circular economy approach. Finally, the analysis of the valorization of mining waste in other elements of the construction sector is recommended to continue promoting the circular economy and sustainable development.

Resumen La minería en el Perú es la más grande actividad económica aportando un porcentaje considerable al Producto Bruto Interno nacional. Sin embargo, el proceso de esta actividad evidencia diversos conflictos socio-ambientales. La generación de residuos mineros o expresados como relaves mineros provenientes de los diversos procesos es una amenaza latente que afecta las esferas del desarrollo sostenible. Este estudio tuvo como objetivo la propuesta de valorización de relaves mineros como áridos para la construcción de carreteras en la región andina del Perú bajo un enfoque de economía circular. En consecuencia, se realizó diversos análisis para evaluar su viabilidad como el factor meteorológico de precipitación, acidez o alcalinidad, elementos presentes en la muestra, granulometría, California Bearing Ratio (CBR) y prueba Marshall. Los resultados han demostrado que la propuesta cumple con los parámetros establecidos a nivel nacional con una estabilidad de 877,67 kg y un aprovechamiento del 25% de los relaves mineros. En conclusión, el uso de relaves mineros como áridos para la construcción es una propuesta viable para la construcción de carreteras bajo un enfoque de economía circular. Finalmente, se recomienda el análisis de valorización de residuos mineros en otros elementos del sector construcción para continuar promoviendo la economía circular y desarrollo sostenible.

ABSTRACT Introduction: The extruded products in Cuba are produced from corn meal, a raw material obtained from imported corn grain. Extrusion technology allows the production of products from flour mixtures. Objective: To determine the adequate proportion of the corn and rice flour mixture and the extruder operating temperature. Materials and Methods: A granulometric analysis of both flours was made. Mixtures of corn flour (M) and rice four (A) were prepared. An industrial extruder with a capacity of 200 kg/h and a nozzle diameter of 4 mm was used. The experimental variables were M/A ratio (90 M/10 A, 75 M/25 A y 60 M/40 A) and temperature (190 y 210 °C). The investigated variables were expansion and humidity as well as those corresponding to the sensorial evaluation. Results and Discussion: Rice flour shows a finer granulometry than corn flour; this may limit its level of addition to the mixture. The investigated variables were found to be independent of temperature, but dependent on the proportion of the flours. From the desirability function, the best result was obtained for 60 M/40 A and 190 ºC. Conclusions: Corn and rice flours have similar starch content. The level of rice flour addition is determined by the incorporation of smaller particle sizes into the mixture. The overall sensory quality, according to the desirability function, was 7.4, equivalent to good.

RESUMEN Introducción: Los productos extruidos en Cuba se elaboran a partir de harina de maíz, materia prima obtenida de la importación del maíz en grano. La tecnología de extrusión permite elaborar productos a partir de mezclas de harinas. Objetivo: Determinar la proporción adecuada de la mezcla de harinas de maíz y arroz y la temperatura de operación del extrusor. Materiales y Métodos: Se realizó un análisis granulométrico de ambas harinas. Se prepararon mezclas de harina de maíz (M) y harina de arroz (A). Se utilizó un extrusor industrial de 200 kg/h de capacidad y 4 mm de diámetro de boquilla. Las variables experimentales fueron la proporción M/A (90 M/10 A, 75 M/25 A y 60 M/40 A) y la temperatura (190 y 210 °C). Las variables investigadas fueron el índice de expansión y la humedad, así como las correspondientes a la evaluación sensorial. Resultados y Discusión: La harina de arroz presenta una granulometría más fina que la de maíz; ello puede limitar su nivel de adición a la mezcla. Las variables investigadas resultaron independientes de la temperatura, pero dependientes de la proporción de las harinas. A partir de la función de deseabilidad se obtuvo el mejor resultado para 60M/40A y 190 °C. Conclusiones: Las harinas de maíz y arroz tienen un contenido de almidón similar. El nivel de adición de harina de arroz queda determinado por la incorporación a la mezcla de partículas con menor tamaño. La calidad sensorial global, según la función de deseabilidad fue de 7,4 equivalente a buena.

Resumen El objetivo fue determinar un modelo matemático para calcular la velocidad de deposición del lodo resultante del lavado de áridos de la Unidad Empresarial de Base del Jobo de Sagua de Tánamo, el cual es transportado por tuberías. Se efectuó muestreo, análisis granulométricos y densimétricos y se utilizó un diseño de experimento factorial completo con cuatro pruebas y dos réplicas cada una. La variable de entrada, porcentaje de sólidos, se estudió a cuatro niveles (4 %, 12 %, 20 % y 28 %). Se determinó que la arcilla contenida en el lodo por su granulometría predominante inferior a 40 µm clasifica como limo. Asimismo, se reveló que la densidad del sólido es 1 901 kg/m3. Se compararon los resultados de la velocidad de deposición determinados por medición indirecta y los que se predicen por cálculos utilizando el modelo de Durand, con el objetivo de mejorar la precisión y confiabilidad de este, obteniendo un error relativo de coincidencia inferior al 5%. Se determina una función de corrección que cuantifica la relación entre la velocidad de sedimentación gravitatoria y la velocidad de deposición.

Abstract The objective was to determine a mathematical model to calculate the deposition velocity of the mud resulting from the washing of aggregates from the Jobo Base Business Unit of Sagua de Tánamo, which is transported by pipelines. Sampling, granulometric and densimetric analyzes were carried out and a complete factorial experiment design with four tests and two replications each was used. The input variable, percentage of solids, was studied at four levels (4%, 12%, 20% and 28%). It was determined that the clay contained in the mud, due to its predominant granulometry of less than 40 µm, classifies as silt. It was also revealed that the density of the solid is 1,901 kg/m3. The results of the deposition velocity determined by indirect measurement and those predicted by calculations using the Durand model were compared, with the aim of improving its precision and reliability, obtaining a relative coincidence error of less than 5%. A correction function is determined that quantifies the relationship between gravitational sedimentation velocity and deposition velocity.

ABSTRACT Ore from the Yarusyacán District was analyzed in this research study, revealing the presence of sphalerite type 2, with a particle size ranging from 35 to 150 microns. Other species found included quartz, pyrite, pyrrhotite, calcium and potassium silicates, calcium carbonates, galena, chalcopyrite, and iron hydroxides. Based on the mineralogical characterization, laboratory tests were conducted that showed that dosing a secondary collector known as cuprocyanide can control the recovery and quality of the zinc concentrates in the third cleaning feed. Results showed that a 35 g/t dosage of cuprocyanide recovered 73.80% of zinc, whereas a 50 g/t dosage recovered only 52.94%. This demonstrated that both zinc grade and recovery increase when cuprocyanide is dosed in greater quantities; however, the excess of this reagent tends to decrease said values.

RESUMEN En este trabajo de investigación, se analizó un mineral de la zona de Yarusyacán, cuya mineralogía reveló la presencia de esfalerita tipo 2 con una granulometría de 35 a 150 micras, además de especies como cuarzo, pirita, pirrotita, silicatos de calcio y potasio, carbonatos cálcicos, galena, calcopirita e hidróxidos y óxidos de hierro. Sobre la base de la caracterización mineralógica, se realizaron pruebas a nivel de laboratorio que demostraron que la recuperación y la calidad de los concentrados de zinc pueden ser controladas a partir de la dosificación de un colector secundario, cuprocianuro, en la alimentación de la tercera limpieza. Los resultados de las pruebas demostraron que la dosificación de 35 g/t recuperó el 73.80% de Zn; en cambio, la dosificación de 50 g/t recuperó solo el 52.94%. De esta manera, quedó demostrado que tanto la ley como la recuperación de zinc aumentan cuando se dosifica cuprocianuro en mayor cantidad; sin embargo, el exceso de este reactivo tiende a disminuir estos valores.

Abstract Finding ways to reuse residue is an alternative not only to reduce its presence in urban and natural environments, but also to reduce costs and consumption of resources by industries. The objective of this paper is to evaluate the properties of concretes made by replacing conventional coarse and fine aggregates with marble residue. Morphological, granulometry, specific gravimetry and crystalline phase analyses were carried out in the aggregates. The composition of the constituents, by mass, was 1:1,2:3 of Portland cement CPIII-32 RS, fine aggregates, and coarse aggregate, respectively, with the addition of 0.4 of water, molded and cured in water. About 25 concrete samples were made, varying the amount of coarse/fine aggregate in the cement mass according to the aggregates proportions of: A= 100% gravel/ 100% sand, B= 100% coarse RRO/ 50% fine RRO + 50% sand, C= 50% coarse RRO + 50% gravel/ 100% fine RRO, and D = 100% coarse RRO/100% fine RRO. The cylindrical samples measuring ∅50 x 100 mm were subjected to water absorption and compressive strength tests, and the results were compared with standards and literature. The water absorption was smaller than 2.5% and the compressive strength values were between 27-33 MPa, close to the resistance of cement used. Composition B presented the best results among the others, indicating the possibility of using the residue from marble for production of concretes for various purposes such as low load paving, sidewalks, blocks, among others. However, for interlocking floors, higher performance cement should be used to achieve the required strength. This type of concrete adds value to the residue and mitigates environmental impacts. environments industries Morphological granulometry constituents 11,23 1123 1 1,2 3 2 1:1,2: CPIII32 CPIII 32 CPIII-3 RS respectively 04 0 4 0. coarsefine A gravel sand 50 C RRO100 RRO/100 ∅5 10 tests literature 5 2.5 2733 27 33 27-3 MPa others paving sidewalks blocks However floors impacts 11 23 11,2 112 12 1, 1:1,2 CPIII3 CPIII- RRO10 RRO/10 ∅ 2. 273 27- 11, 1:1, RRO1 RRO/1 1:1 1:

Resumo Encontrar formas de reaproveitar resíduos é uma alternativa não só para reduzir sua presença em ambientes urbanos e naturais, mas também para reduzir custos e consumo de matérias primas pelas indústrias. O objetivo deste trabalho é avaliar as propriedades de concretos fabricados através da substituição de agregados graúdos e miúdos convencionais por resíduo de mármore. Foram realizadas análises de morfologia, granulometria, massa específica e da fase cristalina dos agregados. A composição dos constituintes, em massa, foi 1:1,2:3 de cimento Portland CPIII-32 RS, agregados miúdos e agregados graúdos, respectivamente, com adição de 0,4 de água, moldados e curados em água. Foram confeccionadas cerca de 25 amostras de concreto, variando a quantidade de agregado graúdo/fino na massa de cimento de acordo com as proporções de agregados de: A= 100% brita/ 100% areia, B= 100% RRO grosso/ 50% RRO fino + 50% areia, C= 50% RRO grosso + 50% cascalho/ 100% RRO fino, e D = 100% RRO grosso/100% RRO fino. As amostras cilíndricas medindo ∅50 x 100 mm foram submetidas a testes de absorção de água e resistência à compressão, e os resultados obtidos foram comparados com algumas normas e com a literatura. A absorção de água foi inferior a 2,5% e a resistência à compressão ficou entre 27-33 MPa, valor próximo à resistência do cimento utilizado. A composição B apresenta os melhores resultados entre as demais, indicando a possibilidade de utilização do resíduo do mármore para produção de concretos para diversas finalidades como pavimentação de baixa carga, calçadas, blocos, entre outros. No entanto, para pisos intertravados, deve-se utilizar cimento de maior desempenho para atingir a resistência necessária. Esse tipo de concreto agrega valor ao resíduo e mitiga os impactos ambientais. naturais indústrias morfologia granulometria constituintes 11,23 1123 1 1,2 3 2 1:1,2: CPIII32 CPIII 32 CPIII-3 RS respectivamente 04 0 4 0, graúdofino graúdo brita areia 50 C cascalho grosso100 grosso/100 ∅5 10 literatura 5 2,5 2733 27 33 27-3 MPa utilizado demais carga calçadas blocos outros entanto intertravados devese deve se necessária ambientais 11 23 11,2 112 12 1, 1:1,2 CPIII3 CPIII- grosso10 grosso/10 ∅ 2, 273 27- 11, 1:1, grosso1 grosso/1 1:1 1:

RESUMO Neste estudo objetivou-se caracterizar a zona hiporreica de um trecho do rio Ipojuca através de análises dos sedimentos e da meiofauna desse ambiente. Foram realizadas coletas de amostras em dois pontos, (Ponto 1: 8º17'28.2” S; 35º59'38.6” W e Ponto 2: 8º17'48.1” S; 35º56'12.2” W), e em três períodos: verão (novembro/2018), período de transição (março/2018) e inverno (junho/2018). O material mais representativo foi classificado como silte, variando entre grosso, médio e fino. Foram contabilizados 678 indivíduos da meiofauna, distribuídos em quatro taxa mais representativos, Rotifera (41%), Nematoda (40%), Annelida (11%) e Copepoda (5%). A análise PERMANOVA indicou diferenças significativas para os fatores Tempo (p = 0,0009) e Espaço (p = 0,0261). Não houve relação significativa entre a estrutura da comunidade da meiofauna e as variáveis do ambiente hiporreico. As diferenças observadas podem estar ligadas a qualidade da água, que também variou entre os pontos e os períodos estudados. objetivouse objetivou se 1 8º1728.2 8º17282 º 8º17 28.2 28 2 8º17'28.2 S 35º5938.6 35º59386 35º59 38.6 38 6 35º59'38.6 8º1748.1 8º17481 48.1 48 8º17'48.1 35º5612.2 35º56122 35º56 12.2 12 35º56'12.2 W, , W) novembro/2018, novembro2018 novembro novembro/2018 2018 (novembro/2018) março/2018 março2018 março (março/2018 junho/2018. junho2018 junho junho/2018 . (junho/2018) silte grosso fino 67 representativos 41%, 41 41% (41%) 40%, 40 40% (40%) 11% 11 (11% 5%. 5 5% (5%) p 0,0009 00009 0 0009 0,0261. 00261 0,0261 0261 0,0261) hiporreico água estudados 8º1728 8º1728. 8º1 282 28. 8º17'28. 35º5938 35º5938. 35º5 386 38. 3 35º59'38. 8º1748 8º1748. 481 48. 4 8º17'48. 35º5612 35º5612. 122 12. 35º56'12. novembro201 novembro/201 201 (novembro/2018 março/201 março201 (março/201 junho201 junho/201 (junho/2018 (41% (40% (11 (5% 0,000 0000 000 0026 0,026 026 8º172 8º 8º17'28 35º593 35º 35º59'38 8º174 8º17'48 35º561 35º56'12 novembro20 novembro/20 20 (novembro/201 março/20 março20 (março/20 junho20 junho/20 (junho/201 (41 (40 (1 (5 0,00 00 002 0,02 02 8º17'2 35º59'3 8º17'4 35º56'1 novembro2 novembro/2 (novembro/20 março/2 março2 (março/2 junho2 junho/2 (junho/20 (4 ( 0,0 8º17' 35º59' 35º56' novembro/ (novembro/2 março/ (março/ junho/ (junho/2 0, (novembro/ (março (junho/ (novembro (junho

ABSTRACT This study characterized the hyporheic zone of a stretch of the Ipojuca River through analysis of the sediments and meiofauna of this environment. Samples were collected at two points (Point 1: 8°17'28.2” S; 35°59'38.6” W and Point 2: 8°17'48.1” S; 35°56'12.2” W) and in three periods: summer (November/2018), transition period (March/2018), and winter (June/2018). The most representative material was classified as silt, varying between coarse, medium, and fine. 678 meiofauna individuals were counted, distributed in four more representative taxa, Rotifera (41%), Nematoda (40%), Annelida (11%), and Copepoda (5%). The PERMANOVA analysis indicated significant differences for the period (p = 0.0009) and space (p = 0.0261) factors. There was no significant relationship between the meiofauna community structure and hyporheic environment variables. The observed differences may be linked to water quality, which also varied between the points and periods studied. 1 8°1728.2 817282 8°17 28.2 8 17 28 2 8°17'28.2 S 35°5938.6 3559386 35°59 38.6 35 59 38 6 35°59'38.6 8°1748.1 817481 48.1 48 8°17'48.1 35°5612.2 3556122 35°56 12.2 56 12 35°56'12.2 November/2018, November2018 November November/2018 , 2018 (November/2018) March/2018, March2018 March March/2018 (March/2018) June/2018. June2018 June June/2018 . (June/2018) silt coarse medium fine 67 counted taxa 41%, 41 41% (41%) 40%, 40 40% (40%) 11%, 11 11% (11%) 5%. 5 5% (5%) p 0.0009 00009 0 0009 0.0261 00261 0261 factors variables quality studied 1728 8°1728. 81728 817 8°1 282 28. 8°17'28. 5938 35°5938. 355938 3559 35°5 386 38. 3 35°59'38. 1748 8°1748. 81748 481 48. 4 8°17'48. 5612 35°5612. 355612 3556 122 12. 35°56'12. November201 November/201 201 (November/2018 March201 March/201 (March/2018 June201 June/201 (June/2018 (41% (40% (11% (5% 0.000 0000 000 0.026 0026 026 172 8°1728 8172 81 8° 8°17'28 593 35°5938 35593 355 35° 35°59'38 174 8°1748 8174 8°17'48 561 35°5612 35561 35°56'12 November20 November/20 20 (November/201 March20 March/20 (March/201 June20 June/20 (June/201 (41 (40 (11 (5 0.00 00 0.02 002 02 8°172 8°17'2 35°593 35°59'3 8°174 8°17'4 35°561 35°56'1 November2 November/2 (November/20 March2 March/2 (March/20 June2 June/2 (June/20 (4 (1 ( 0.0 8°17' 35°59' 35°56' November/ (November/2 March/ (March/2 June/ (June/2 0. (November/ (March/ (June/ (November (March (June

Abstract Beach classification models are widely used to describe the state of the beach in response to the prevailing environmental conditions and have set the theoretical grounds for equilibrium and in-plant profile models of a beach and their various applications. This study determined the morphodynamic state of 54 sandy biogenic beaches on the northeast coast of Cuba. This was done based on the identification of coastal geoforms found in land works between August 2018 and March 2022 and the geoforms identified in high-resolution satellite images from Google Earth Pro (CNES/Airbus, Maxar Technologies). In addition, on 12 representative beaches on the northeast coast, we explored whether the coastal geoforms indicative of certain morphological states observed during fieldwork match those predicted by the Ω dimensionless parameter or Dean’s index, which classified beaches as dissipative, reflective, and intermediate. The main geomorphological features include an average beach width of more than 50 m, an 11 m-wide face, and a narrow or absent flat zone with a mean height of 1.35 m, lacking cusps and rhythmic topography, except for 26 % of beaches and only in winter. The submerged zone shows a low sand bar without rip currents. Coral reefs that protect the beaches from the highest waves in 93 % of the cases represent the distinctive geomorphological feature of the beaches studied. The dimensionless parameter confirmed that the beaches of Cuba’s northeast coast correspond to intermediate morphodynamic states with a trend toward reflective rather than dissipative modal states. These findings correspond to the coastal geoforms and sediment granulometry on the beaches studied. The figures obtained with the dimensionless parameter Ω and the sedimentary characteristics of the beaches are consistent with the characteristics of intermediate beaches reported by Australian researchers, but we did not find the geoforms for intermediate beaches reported by them. The beaches studied showed no rip currents, chains of coastal furrows, low-tide terraces, marked rhythmic topography, and cusps. Other studies have also pointed out that the beach classification proposed by Australian researchers, which considers the characteristics of waves and the sedimentation rate, is not always applicable. In the study area, this is mainly due to the presence of coral reefs close to the coast, low wave energy, and the influence of geological factors, in addition to the prevalence of longitudinal over transverse sand transport. Our results confirm that beach classification considering their morphodynamic state is essential to understanding the spatio-temporal dynamics of the hydrodynamic processes on beaches and contributes to a better local and regional knowledge of them. In addition, they highlight that the hydrodynamic and sedimentary characteristics of each coastline should be studied before using beach equilibrium profile models and the equations derived from them for erosion control actions.

Resumen Los modelos de clasificación de playa son ampliamente usados para describir el estado de la playa en respuesta a las condiciones ambientales reinantes y han establecido las bases teóricas sobre los modelos de perfil de equilibrio y en planta de una playa y sus diversas aplicaciones. En el estudio se determina el estado morfodinámico en 54 playas biogénicas arenosas del litoral nororiental de Cuba, a partir de la identificación de las geoformas litorales encontradas en trabajos de terrenos, para el periodo comprendido entre agosto de 2018 y marzo del año 2022, y las geoformas identificadas en imágenes satelitales de alta resolución de Google Earth Pro (CNES/Airbus, Maxar Technologies). Además, se comprobó en 12 playas representativas del litoral nororiental, si las geoformas litorales observadas en los trabajos de campo, indicativas de ciertos estados morfológicos, se corresponden con las pronosticadas mediante el parámetro adimensional Ω o Índice de Dean, que permite clasificar las playas en disipativas, reflejantes e intermedias. Como rasgos geomorfológicos fundamentales destacan un ancho medio de la playa superior a 50 m, una cara de 11 m de ancho y bermas estrechas o ausentes, con altura media de 1.35 m, sin la presencia de cúspides y topografías rítmicas, excepto en el 26% de las playas y únicamente en la etapa invernal. En la parte sumergida aparece una barra de arena de poca altura, sin la presencia de corrientes de resaca. La presencia de arrecifes coralinos que protegen las playas del oleaje de mayor altura, en el 93% de los casos, constituye el rasgo geomorfológico más significativo de las playas objeto de estudio. El cálculo del parámetro adimensional confirmó que las playas del litoral nororiental de Cuba corresponden a estados morfodinámicos de tipo intermedio y tienden más a estados modales reflejantes que disipativos, resultados que se corresponden con las geoformas litorales y la granulometría de los sedimentos encontrados en las playas objetos de estudio. Aun cuando las características reportadas por investigadores australianos, para playas intermedias coincidan con los valores pronosticados mediante el cálculo del parámetro adimensional Ω y con las características sedimentarias de las playas, las geoformas reportadas por estos, para playas intermedias, no fueron encontradas en las playas objeto de estudio. En ellas no aparecen corrientes de retorno, cadenas de surcos litorales, terrazas de bajamar, marcada topografía rítmica y cúspides. Otros estudios también han señalado que no siempre se cumple la clasificación de las playas, que tiene en cuenta las características de las olas y la velocidad de caída de los sedimentos, propuestas por investigadores australianos, debido particularmente a la presencia de arrecifes coralinos cercanos a la costa, la baja energía del oleaje y el control geológico. A ello habría que añadir el predominio del transporte longitudinal de arena sobre el transporte transversal en el área de estudio. Los resultados confirman que la clasificación de las playas, atendiendo a su estado morfodinámico es esencial para comprender la dinámica espacio-temporal de los procesos hidrodinámicos que tienen lugar en las playas y un mejor conocimiento local y regional de las mismas. Además, reafirman la necesidad de contar con estudios específicos de las características hidrodinámicas y sedimentarias propias de cada litoral, antes de extrapolar modelos de perfil de equilibrio en playas y las ecuaciones que se deriven de ellos en las actuaciones para el control de la erosión.