Sirvi Autor "Silva, F.C." järgi
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Kirje Characterization of materials used in the manufacture of ceramic tile with incorporation of ornamental rock waste(2020) Luiz, N.F.; Cecchin, D.; Azevedo, A.R.G.; Alexandre, J.; Marvila, M.T.; Silva, F.C.; Paes, A.L.C.; Pinheiro, V.D.; Carmo, D.F.; Ferraz, P.F.P.; Hüther, C.M.; Cruz, V.M.F.; Barbari, M.The production of ceramic tiles, such as tiles, has a great environmental impact, either in the extraction of natural raw materials or gas emissions in the burning stages. The use of industrial solid waste in ceramic materials can contribute to the reduction of these impacts, according to the characteristics of solid waste and its interaction with ceramic materials in the processing steps. Thus, this study aimed to characterize the materials needed to make a ceramic tile with incorporation of ornamental rock waste (ORW), thus evaluating its main characteristics regarding the feasibility of this incorporation. The physical characterization of the clays used in the production of ceramic artifacts was performed, and for the waste the mineralogical analyzes were performed, through x-ray diffraction (XRD), microstructure analysis from confocal optical microscopy, after sintering the prototypes and chemical analysis by X-ray spectroscopy (EDX). Soon after the raw materials went through the step of conformation and preparation of the prismatic specimens by the process of extrusion of the ceramic mass, with an incorporation of the ORW in 0% and 15% of the ceramic mass, for its subsequent The prototypes were sintered at three different temperatures (850 °C, 950 °C and 1,050 °C). The specimens were submitted to technological tests of mechanical resistance, water absorption, firing shrinkage and porosity to evaluate the incorporation viability. The results indicated the presence of quartz particles in all raw materials, and also that the clays of the study region are predominantly kaolinitic. The presence of these materials in the ceramic masses directly influences the micrographs, because they result in the formation of liquid phase, inert particles that can turn the site into a stress concentration point and when incorporated in the ORW the specimens met the technical specifications of the Brazilian standard for application on ceramic tiles. The results found in the technological tests carried out, that the incorporation of 15% of ornamental rock waste in both clays did not affect the tile properties, indicating the feasibility of incorporating this waste in civil construction, minimizing the impacts generated.Kirje Ecological footprint of beef consumption in the state of Rio de Janeiro - Brazil(2021) Cunha, J.B.; Cecchin, D.; Amaral, P.I.S.; Silva, F.C.; Azevedo, A.R.G.; Salcedo, I.L.; Hüther, C.M.; Sousa, F.A.; Carmo, D.F.The beef production chain can cause considerable impacts on the environment depending on how it is carried out. The need to discuss the impact of the consumption of this food in a country whose production base is mainly agricultural and livestock is relevant in view of the environmental degradation and scarcity of resources. In this work, the ecological footprint of beef consumption was evaluated using the state of Rio de Janeiro as a case study. Data were collected such as population, productive capacity, annual consumption, cattle weight, grazing equivalence factor. Calculations of livestock density, consumption per capita, productivity, number of oxen, area per capita, and total area required were also carried out. The value found for Total Ecological Footprint was 1,117,995.22 gha and for Ecological Footprint per capita was 0.065 gha. It was found that the ecological footprint per capita is higher than the area destined for each inhabitant of the State which is 0.019 ha. It can be inferred that the consumption of beef as it is currently carried out harms the ecosystem in which production is inserted.Kirje Management alternatives for sandy soils to overcome edaphic limitations in irrigated okra cultivation(Estonian University of Life Sciences, 2024) Rodrigues, N.F.; Tavares, S.R.L.; Silva, F.C.; Hüther, C.M.; Corrêa, G.M.; Oliveira, J.R.; Hamacher, L.S.; Clemente, E.P.Sandy soils are often unsuitable for agriculture due to their poor physical and chemical properties. However, using conditioners can improve these parameters, making these soils viable for cultivation. This study evaluated Red-Yellow Argisol (Clay), Biochar, and Ceramic residues as soil conditioners for Planosol. The experiments were conducted in pots in a greenhouse and the experimental design was completely randomized with three treatments and five replications, compared to a control (100% P). Treatments included Clay (50% P + 570.6 t ha-1 A), Biochar (50% P + 189.9 t ha-1 B), and Ceramic (50% P + 459.9 t ha-1 C). Okra (Abelmoschus esculentus L.) was used to assess the impact on development and productivity over 90 days from transplanting (DAT). Granulometry of conditioners, and the carbon, hydrogen, nitrogen, and ash content were analyzed. For constructed soils, granulometry, bulk density, particle density, and water retention capacity (CRA) were measured before planting. Chemical parameters, including Ca²⁺, Mg²⁺, K⁺, Na⁺, Al³⁺, H⁺, pH, and others, were measured at 0 and 90 DAT. Okra growth parameters, such as height, stem diameter, leaf number, leaf area, stomatal conductance, and chlorophyll a fluorescence dry biomass and leaf nutrient contents (N, P, K, Ca, Mg, Na) were assessed at 90 DAT. Results indicated that conditioners improved the physical and chemical properties of the Planosol and the physiological parameters of okra. Biochar increased phosphorus and potassium, while Clay enhanced nitrogen and sodium for okra cultivation.Kirje Productive efficiency and density and viscosity studies of biodiesels from vegetable oil mixtures(2021) Correia, R.C.B.; Silva, F.C.; Barros, M.M.; Maria, A.C.L.; Cecchin, D.; Souza, L.A.; Carmo, D.F.Currently in Brazil the minimum content of biodiesel in mixtures is 11% and, according to Brazilian laws, the goal is to reach 15% in volume in diesel fuel available for final consumers by 2023. Therefore, studies about different matrices of biodiesel and distinct mixtures are essential. The present work had two goals, the first one was to analyse physico-chemical properties of 16 biofuels produced from soybean and cotton oils, using S10 diesel, in mixtures B8, B10, B20 and B30. The second goal was to verify the vantages and disadvantages of biodiesel production through prior mixing of the oils, before and after the transesterification process. All biofuels produced presented results of specific mass values at 20 °C and kinematic viscosity at 40 °C within the limits established by ANP Resolution no 30/2016 and International Resolutions. The soybean B20 biofuel showed the best overall results, with the second highest production yield of 65.36%, the fifth lowest kinematic viscosity with 3.48 mm s -1 . The mixture of soybean and cotton oils before the transesterification process presented the highest production yield when compared with the production from a single oil or biodiesel mixtures. The results found proved to be satisfactory and corroborate to continue with the increase of biodiesel in the mixture with diesel to B15 until 2023 and support the possibility of planning for a gradual increase of this mixture in the following years.Kirje Response surface for biodiesel production from soybean oil by ethylic route(2020) Souza, L.A.; Silva, F.C.; Maria, A.C.L.; Belem, A.L.; Cecchin, D.; Barros, M.M.Petroleum has been the most consumed energy source in the world, but it tends to run out due its non-renewable character. Among biofuels, biodiesel has emerged as the main candidate to substitute petroleum diesel. The present study aimed to identify the maximum yield point of biodiesel production by generating a response surface using molar ratio, temperature and agitation time as independent variables, and yield as a dependent variable. From the response surface, it is observed that the increase in temperature and reaction time leads to reduced yield. The configuration that resulted in maximum yield of 93.30% was 12:1 molar ratio, 30 °C temperature and 30-minute reaction time. From the chromatographic analysis it was possible to identify five different fatty acids in the composition of the biodiesels. Total saturated fatty acids (palmitic and stearic acids) ranged from 41.53% to 42.09% and total unsaturated fatty acids including monounsaturated and polyunsaturated fatty acids (oleic, linoleic and linolenic acids) ranged from 57.92% to 58.48%. According to the results of the physicochemical analyses, the specific mass at 68°F is in agreement with Brazilian, American and European specifications, ranging from 877.46 kg m-3 to 879.64 kg m-3 . The kinematic viscosity at 104 °F ranged from 4.49 mm² s -1 to 4.82 mm² s -1 . The acid value obtained did not vary within the limits established by the norms, and values between 0.54 and 2.74 mg KOH g -1 were observed.Kirje Sustainability indicators in cooperative management of recyclable materials(2020) Aramian, C.B.; Barcelos, F.; Silva, F.C.; Cecchin, D.; Azevedo, A.R.G.; Carmo, D.F.Following the promulgation of the National Solid Waste Policy in 2010, legal provisions, government programs and sectoral agreements have been implemented, but without the expected efficiency in relation to recycling. It should be noted that Cooperatives of Recyclable Material Pickers (CRMP) should play a leading role in this regard, but they do not have adequate management to be economically, socially and environmentally sustainable, depending on assistance to maintain the activity. Aiming to elucidate this issue, in this paper was made an institutional diagnosis of the category of waste pickers using the Gramacho region in the city of Duque de Caxias (Rio de Janeiro) as a case study. It was carried out an evaluation of the historical context of the neighbourhood, and it was drawn up a semi-structured questionnaire in 12 of the 18 cooperatives in the region. The data were interpreted through a SWOT matrix and the Venn diagram. A matrix was proposed and elaborated with 15 sustainability indicators specific to the CRMC reality in order to evaluate and monitor the management of cooperatives. After collecting the primary data, it was possible to validate the matrix of indicators with indexes of cultural, economic, political and ecological sustainability of the cooperatives. It was found that the matrix of indicators facilitated the understanding of the data and the comparison between the indicators. This tool can help decision-making, creation of action plans and identification of demands by the cooperative waste pickers themselves, without the presence of an analyst or technician.