Disertación/Tesis

2022
Disertaciones
1
  • PRISCILA DE ALMEIDA SILVA
  • KETALIZATION OF ETHYL LEVULINATE FOR THE PRODUCTION OF POTENTIAL BUILDING BLOCKS IN ORGANIC SYNTHESIS

  • Líder : RAQUEL VIEIRA MAMBRINI
  • MIEMBROS DE LA BANCA :
  • ADRIANA AKEMI OKUMA
  • CLEVERSON FERNANDO GARCIA
  • EUDES LORENCON
  • Data: 14-jul-2022


  • Resumen Espectáculo
  • The intensification of environmental pollution caused by the constant consumption of products of fossil origin has been driving the development of substitutes from sustainable sources, such as those derived from lignocellulosic biomass. The objective of the present work was to synthesize an organic compound with the potential to be used as a building block in organic syntheses from the biomass derivative of ethyl levulinate through the ketalization reaction using the polyalcohol pentaerythritol in the presence of two types of catalysts, carboxylate of mesoporous niobium (CNbM), developed by our research group and the commercial cationic resin Amberlyst®15.

    The development and characterization of CNbM was the object of study of our research group. Since this material proved to be very promising as a catalyst, it was chosen for testing in ketalization reactions within the scope of this dissertation. The cationic resin (Amberlyst®15) was used as a model catalyst since the literature correlates its use with high conversion rates and selectivity for the formation of the ketal group; with this, the results obtained between the two catalysts already described will be compared.
    The present work developed a methodology for the synthesis of the CNbM catalyst. Through the characterization techniques by absorption spectroscopy in the infrared region, thermogravimetry, and X-ray diffraction, it was possible to observe evidence of the occurrence of coordination of the ligand to the metal and consequent obtaining material, based on literature data. The acidity measurement of the niobium-based material was equal to 0.94 mmolH+ gsol-1 which, compared to Amberlyst®15 (4.42 mmolH+ g-solid-1) appears to be of a more moderate nature.
    The ketalization reaction between ethyl levulinate ester and pentaerythritol alcohol took place in a Dean Stark system and according to the characterization analysis by infrared absorption spectroscopy and mass spectrometry with electrospray ionization, the ketal of interest was formed.

2
  • MARIANA DE AGUILAR SANTOS
  • EVALUATION OF CHEMICAL AND BIOLOGICAL ATTRIBUTES OF CONSTRUCTED NICHES USING IRON ORE TAILING: an alternative for the revitalization of degraded areas.

  • Líder : ANDREA RODRIGUES MARQUES
  • MIEMBROS DE LA BANCA :
  • ANDREA RODRIGUES MARQUES
  • ANGELA DE MELLO FERREIRA
  • FABIANA DA CONCEICAO PEREIRA TIAGO
  • FERNANDA BADOTTI
  • PATRICIA SUELI DE REZENDE
  • VALERIA CRISTINA PALMEIRA ZAGO
  • Data: 25-ago-2022


  • Resumen Espectáculo
  • The iron ore extraction industry is one of the important sectors for the Brazilian economy, especially in the Quadrilátero Ferrífero region, Minas Gerais. This activity generates a significant environmental impact on the Campo Rupestre ecosystem and the disposal of the generated tailings is a recurring socio-environmental problem, especially after the failure of two tailings dams in the state. The use of Constructed Niche (CN) is a recently presented technique, which has as its constituent iron ore tailings, topsoil, and binder. The application of the NC technique aims to mimic pre-existing ecological niches in areas degraded by mining activities, by bringing biotic components from the place of interest. This study aimed to characterize the topsoil of a non-degraded area of CR in terms of chemical and mineralogical composition and fertility; to evaluate the effects of new CN constituents (such as bentonite clay and fungal mycelium biocomposite) on its mechanical property and on its biological attributes, such as: microbial biomass carbon (MBC), basal respiration (BR) and metabolic quotient (qCO2 ) and observe the presence of photobiont organisms during the incubation period from 7 and 180 days. The CNs were made by adding different proportions of topsoil from CR of the Serra da Piedade, iron ore tailings (30%), cement (5%), clay (10%) and biocomposite (10%). XRD and XRF analyzes of topsoil identified minerals such as hematite, quartz and goethite and high proportions of Fe oxide and silicon dioxide. Fertility analyzes showed low concentration of nutrients, including Ca, K, P, and CEC (cation exchange capacity), as well as low content of organic matter, C, N and acidic pH. These observed features are typical of ferruginous CR topsoil. The new binders used in the manufacture of CNs did not provide strength to the material, making it necessary to test new proportions in future studies. Only the cement conferred resistance to the CN, as it is a good binder, promoting the cohesion of the constituent particles of the module (topsoil + tailings). The MBC between the controls and the treatments showed no significant difference when compared between the two incubation times, except for the NC containing the biocomposite. The BR results were low for the controls and topsoil + tailings, but in the treatments containing clay and biocomposite the results were significant. The growth of photobionts such as bryophyte gametophytes, pteridophyte prothallus, angiosperm seedlings and algae were observed in topsoil and topsoil+tailings. For CNs containing cement and clay there was the appearance of fungi during the incubation period and, in the time of 180 days, in addition to fungi, the development of angiosperm was observed on the surface of the CN containing the biocomposite. The analyzes of the present study indicate that the CN made with biocomposite has greater potential to act as life development stimulators.

3
  • PÂMELA VICENTE MARTINS
  • STUDY OF THE ADSORPTION CAPACITY OF ATMOSPHERIC POLLUTANTS IN CHITOSAN-BASED PELLETS AND IRON METAL ORGANIC FRAMEWORK

     

  • Líder : RAQUEL VIEIRA MAMBRINI
  • MIEMBROS DE LA BANCA :
  • LUZIA SERGINA DE FRANCA NETA
  • DIANA QUINTAO LIMA
  • ADRIANA DE ALMEIDA PINTO BRACARENSE
  • Data: 26-ago-2022


  • Resumen Espectáculo
  • The increase in the level of carbon dioxide (CO2) in the atmosphere resulting from anthropogenic emissions is one of the main environmental problems faced by civilization today. The largest source of CO2 emissions worldwide comes from the intensive burning of fossil fuels. As CO2 is one of the main gases responsible for the intensification of the greenhouse effect, the increase in its concentration in the atmosphere causes global warming, which causes numerous environmental impacts. Among the gas separation and purification techniques, the adsorption process has been highlighted as a promising treatment method for presenting advantages such as high efficiency, low energy consumption, easy regeneration, and recycling of adsorbents, in addition to having simple operating conditions, able to operate on a large scale. And to contribute to the adsorption process are the MOFs. Listed by IUPAC as one of the chemical innovations that contribute to a sustainable future, due to their high application potential, particularly acting as adsorbents in gas separation technologies. But because MOFs are a fine powder, they are generally not used in fixed beds due to the large pressure drop these fine particles cause. And to carry out the adsorption process on a larger scale using the fixed bed, these porous materials need to be molded into larger particles, such as pellets. Therefore, the objective of this work was to reproduce the synthesis of a MOF based on iron and terephthalic acid that has already been synthesized by our research group. From the MOF, he synthesized pellets using the natural binder chitosan. The MOF-Fe(BDC) materials, and the Pellets (1:1) and Pellets (2:1) were characterized by IV, TG, XRD, and BET. Through these analyzes, it was possible to infer that the MOF-Fe(BDC) synthesized in this work is the same produced by our research group. And the pellets were obtained and shown to be stable structures. After characterization, MOF-Fe(BDC) and Pellets were applied in gravimetric tests of carbon dioxide adsorption. Since MOF-Fe(BDC) adsorbed 66.60 mg/g of CO2, pellets (1:1) and pellets (2:1) adsorbed 103.60 mg/g and 102.40 mg/g of the pollutant gas, respectively. The materials showed relevant activity as CO2 adsorbents, showing to be promising for application in fixed-bed column.

4
  • ISIS GABRIELLA DA SILVA BATISTA
  • Development of a portable sampler to capture exhaust emissions from diesel cycle vehicles

  • Líder : PATRICIA SUELI DE REZENDE
  • MIEMBROS DE LA BANCA :
  • PATRICIA SUELI DE REZENDE
  • ADRIANA AKEMI OKUMA
  • PATTERSON PATRICIO DE SOUZA
  • EMERSON FERNANDES PEDROSO
  • ARNALDO FREITAS DE OLIVEIRA JUNIOR
  • Data: 30-ago-2022


  • Resumen Espectáculo
  • In recent years, it has been recognized that vehicular emissions have perfomed a fundamental role in climate change, air pollution and the causes of human diseases linked to the emissions of pollutants such as: nitrogen oxides (NOx), carbon dioxide (CO2), volatile organic compounds (VOC), carbon monoxide (CO), and black carbon (BC). These emissions come mainly from heavy vehicles, powered by diesel oil. Due to the rapid growth of the vehicle fleet in the world and the strong dependence on the road modal for the transport of cargo and passengers, gas emissions in developing countries have been growing strongly, which is negatively affecting many populations. The control and inspection of emissions in this segment is ineffective, since there is not enough manpower or the use of analytical methods capable of identifying and quantifying all pollutants emitted via vehicle exhaust during the evaluation of vehicle conditions. In view of this, this work proposed the development of a portable sampler to capture exhaust emissions from diesel cycle vehicles, both for sampling the gaseous fraction and the particulate fraction, in order to allow the identification and quantification of the compounds present in both phases. As a model analyte for the development and optimization of sampling conditions, carbon dioxide gas was selected, as it is a greenhouse gas and is in high concentration in this emission. From research in the literature and different vehicle evaluation standards, models for the sampler were designed until reaching a model to be prototyped according to the precepts of agile prototyping. Real application tests were carried out with bus transport to optimize the application procedure. The portable sampler is a sustainable product, with low noise, easy cost or that does not require electrical energy for maintenance, calibrations for its operation. A method for CO2 determination by gas chromatography with a dielectric barrier discharge ionization detector (GC/BID) was developed. A scan of compounds was performed by means of two-dimensional gas chromatography with flame ionization detector (GCxGC/FID) to indicate other pollutants that can be studied in sequence to this study, bringing versatility to the application of this sustainable product.

5
  • INGRID DAIANE RESENDE
  • EVALUATION OF THE PERFORMANCE OF THE ULTRAFILTRATION PROCESS APPLIED TO LAUNDRY EFFLUENTS AIMING FOR REUSE AND ITS ENVIRONMENTAL FEASIBILITY

  • Líder : PATRICIA SUELI DE REZENDE
  • MIEMBROS DE LA BANCA :
  • LAURA HAMDAN DE ANDRADE
  • LUZIA SERGINA DE FRANCA NETA
  • MARILIA CARVALHO DE MELO
  • PATRICIA SUELI DE REZENDE
  • WAGNER GUADAGNIN MORAVIA
  • Data: 31-ago-2022


  • Resumen Espectáculo
  • Most human activities depend directly on the use of water, and its consumption has increased more and more, due to the rapid growth of population and cities. The reuse of light gray water, domestic wastewater from washbasins, baths and service areas, has been widely recognized due to high volume and easy access effluents. Gray water from laundries can be domestic or industrial. These effluents are lighter in color and have a low concentration of pollutants when compared to other domestic effluents. Above all, studies involving gray water from laundry are relevant, as it is estimated that 10% of all water used in urban areas is consumed in washing clothes. The reuse of laundry effluents is a way to mitigate water scarcity and reduce the pollution of waterways. The Membrane Separation Processes (PSM) have shown to be effective in the application of these effluents, because the membranes work as a selective barrier for the compounds present in a given liquid fraction. Ultrafiltration (UF) has been shown to be efficient in removing suspended solids, turbidity and organic compounds from laundry effluents. The Life Cycle Assessment (LCA) tool makes it possible to assess the potential environmental impacts arising from different effluent treatment technologies. In view of the above, the present work aims to evaluate the technical and environmental feasibility of the ultrafiltration process when applied to the recovery of gray water from domestic and industrial laundries, aiming at its reuse. Polyvinylidene Fluoride (PVDF) polymeric membranes were used in the conformation of hollow fibers packed in two permeation modules in the shell-tube configuration. The membranes were characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR) and solute rejection test. The modules were coupled to the UF system with tangential flow, pressurized system and operating mode with total recycle. They were characterized in terms of hydraulic permeability and limit flow. The permeation tests were carried out with two effluent matrices: domestic and industrial laundries. The feed and the permeate obtained were characterized physicochemically to verify the efficiency of the UF in the removal of compounds, such as organic matter and solid materials in general. The environmental feasibility was analyzed by the ACV tool with the aid of the OpenLCA software version 1.10.3 and considering three scenarios: coagulation-flocculation with reuse in floor washing (scenario 1), UF with reuse in floor washing (scenario 2) and UF with reuse in the washing stage of the laundry itself (scenario 3). The permeation tests with operation of 40 hours for each of the effluent matrices showed stability of the permeate flow. The physical-chemical characterizations showed better removals for the following parameters: Turbidity (93.2% domestic laundry and 92.7% industrial laundry), Chemical Oxygen Demand (68.7% domestic laundry and 62.6% industrial laundry), Solids Totals (45.3% domestic laundry and 44.6% industrial laundry) and Total Dissolved Solids (25.1% domestic laundry and 39.1% industrial laundry). For the analyzed parameters, the matrices showed viability regarding non-potable reuse according to the NBR 13.969/1997 standard, except for class 1. The LCA indicated that scenario 3 was the most environmentally viable, significantly reducing the consumption of potable water.

6
  • FRANCIELE APARECIDA PLOTASIO DUARTE
  • Vinasse improving by electrodialysis combined with nanofiltration aiming at technical and environmental sustainability.

     
     
  • Líder : WAGNER GUADAGNIN MORAVIA
  • MIEMBROS DE LA BANCA :
  • LAURA HAMDAN DE ANDRADE
  • LUZIA SERGINA DE FRANCA NETA
  • PATRICIA SUELI DE REZENDE
  • WAGNER GUADAGNIN MORAVIA
  • Data: 02-sep-2022

  • Resumen Espectáculo
  • The sugar and alcohol industries in Brazil have great economic, social and environmental importance, being responsible for most of the occupation in rural areas and renewable and clean energy production. Despite the contribution to socioeconomic growth with the generation of jobs and wealth, this sector also stands out for its high polluting potential. The vinasse, liquid tailings generated in large quantity in the distillation process of fermented sugarcane juice to obtain ethanol, can trigger a number of impacts on the environment when managed incorrectly, as this effluent has high organic load, low pH, high corrosivity and high potassium contents. One of the alternatives that has been most used by the plants, as a way of final disposal of the effluent, is fertigation, which the vinasse is pumped or transported by channels and sprinkled over the sugarcane fields. However, the application of vinasse in agricultural soil was limited by means of standards, because this effluent contained high concentrations of potassium, which may favor the formation of neutrally charged chemical complexes that are easily leached. The complex formed between K+ and NO3- is environmental worrying because nitrate is a major pollutant of water. Therefore, the present study aims to benefit the vinasse in such a way as to extract its potential, contributing to the eco-efficiency of the ethanol production chain. With the idea of reusing resources in a closed-loop concept that is driven by the principle of “circular economy”, where applications of new techniques and best practices help reduce waste generation, boost recycling and reduce the use of inputs virgins, bringing even more sustainability. With this will be used in the proposed processing, the electrodialysis for the dilution of potassium present in the vinasse, adhering the effluent for fertigation. The cathode concentrate of the electrodialysis will be submitted to nanofiltration, while allowing, ate the same time, to recondition the electrolyte solution and generate a solution rich in potassium, can serve as an input for the fertilizer industry. In order to achieve greater efficiency in the processing of the vinasse, the optimal operational conditions of the processes involved will be determined through of the design technique of experiments. The optimization of operating conditions will be carried out in two stages: through an exploratory phase employing factorial planning to investigate the effects of process factors in order to identify its significance; and then by comparative analysis, where the critical values of the conditions of the factors involved will be determined according to the variable response of interest. It is expected that the results of this research provide support for a better understanding of the phenomena that occur throughout the studied processes and serve as a technical subsidy for applications for the processing of vinasse.

     
     
7
  • NATÁLIA CRISTINA MORAIS FERNANDES
  • Characterization of chemical products obtained from the lignin degradation by fungi Trametes villosa

  • Líder : FERNANDA BADOTTI
  • MIEMBROS DE LA BANCA :
  • ADRIANA AKEMI OKUMA
  • ANA MARIA DE RESENDE MACHADO
  • ARISTOTELES GOES-NETO
  • FERNANDA BADOTTI
  • Data: 27-sep-2022

  • Resumen Espectáculo
  • The biological valorization of lignin as a raw material for the production of fuel and and value-added chemical products allows for the implementation of sustainable biorefineries, as it is a renewable input. Lignin is a highly recalcitrant compound found in all types of plants, which is part of the complex known as lignocellulose. The lignocellulose complex is a fibrous matrix formed by cellulose, hemicellulose and lignin. The best known applications are for cellulose and hemicellulose, and lignin presents the greatest challenge from an industrial point of view, due to the need for depolymerization. However, there is great interest in studying the use of lignin, since it has a structure rich in aromatic groups. In nature, the complete degradation of plants is carried out by fungi and bacteria. Currently, several species of fungi with high potential for lignin degradation are known. The process of degradation of plant material is complex, and different microorganisms, enzymes and finely regulated and interconnected metabolic pathways are involved. This work aims to characterize the chemical products formed from the microbiological degradation of lignin. For this, two different sources of lignin were used as substrate, synthetic alkaline lignin and lignin from sugarcane bagasse and subjected to degradation by the fungus Trametes villosa CCMB561. After 10 days of incubation, the supernatant of experiment was collected and analyzed for the presence of chemical compounds. For the characterization of the substances formed during the process of microbiological degradation of lignin, the samples obtained were submitted to analysis of Gas Chromatography - Mass Spectrometry (GC-MS) and Spectrophotometry in the Ultraviolet and visible region (UV-vis). The degradation of lignin by fungi and enzymes are well described in the scientific literature. However, the products derived from the microbiological of lignin degradation are still little know, thus allowing a vast field for study. The prospection of products from the biological degradation of lignin will expand the potential of application of lignin as a matrix of chemical inputs.

8
  • HENRIQUE GIÁCOMO PEREIRA MENEZES
  • Trapping of polycyclic aromatic hydrocarbons from heavy-duty vehicles emissions using IT-FEX in tube device and analysis by gas chromatography

  • Líder : PATRICIA SUELI DE REZENDE
  • MIEMBROS DE LA BANCA :
  • ADRIANA AKEMI OKUMA
  • CLEVERSON FERNANDO GARCIA
  • JANICE CARDOSO PEREIRA ROCHA
  • PATRICIA SUELI DE REZENDE
  • PATTERSON PATRICIO DE SOUZA
  • Data: 06-oct-2022


  • Resumen Espectáculo
  • The high demand in the delivery of domestic and industrial supplies has caused a significant increase in the amount of cargo vehicles in transit in Brazil, with the road modal as the main one in the transportation of goods and supplies in the national territory. These vehicles, for using mostly diesel oil as fuel, are responsible for a significant emission of volatile organic compounds (VOCs) into the atmosphere, especially a class called polycyclic aromatic hydrocarbons (PAHs), known for their high carcinogenicity. In order to detect and quantify the PAHs from vehicle emissions of this class, we used a standard reference chemical mixture (SQR) of 15 PAHs (from one to six aromatic rings) and developed an analytical method for gas chromatography instrumentation coupled to a dielectric barrier discharge ionization detector (GC/BID), using the IT-FEx polydimethylsiloxane (PDMS) polymer-phase-coated in-tube extraction device. The fabricated devices were subjected to physicochemical characterizations using Thermogravimetric Analysis (TG) and Absorption Spectroscopy in the Infrared (IR) region. The thickness of the polymeric film was evaluated by electronic miscroscopy with a digital camera (10x magnification), resulting in approximately 29 μm. The interaction of the PAHs with the IT-FEx polymeric phase was evaluated, both in aqueous medium (equilibrium kinetics) and in gaseous medium (dynamic phase), being the equilibrium time (aqueous) equal to 25 min and the dynamic analysis (gaseous) equal to 30 s. A better interaction was observed between medium-sized PAHs with PDMS (four aromatic rings) compared to smaller (one to three rings) and larger ones (five to six rings), in both phases (aqueous and gaseous). Emissions from two diesel-powered heavy-duty vehicles (2006 - P5 and 2012 - P7) were evaluated using the IT-FEx coupled to a vehicular sampler (trapping of VOCs by the PDMS film) and analyzing them by GC/BID and GCxGC/FID, which made it possible to observe the difference in the pollutant profile from each emission (mainly through the 3D visualization of the chromatograms referring to the analysis in the GCxGC/FID), with the 2006 vehicle having a greater amount of VOCs detected compared to the 2012. The presence of PAHs was also detected for both (according to their respective retention times compared to those obtained by the standard PAHs solution), being phenanthrene, fluoranthene, benzo[a]anthracene and chrysene for the 2006, and benzo[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[k]fluoranthene for the 2012.

9
  • POLIANA VICENTE MARTINS
  • SYNTHESIS AND CHARACTERIZATION OF HYBRID MEMBRANES CONTAINING COPPER MOF WITH POTENTIAL USE IN WASTEWATER TREATMENT

  • Líder : LUZIA SERGINA DE FRANCA NETA
  • MIEMBROS DE LA BANCA :
  • ALINE BRUNA DA SILVA
  • HELEN CONCEIÇÃO FERRAZ
  • LUZIA SERGINA DE FRANCA NETA
  • PRISCILA PEREIRA SILVA CALDEIRA
  • RAQUEL VIEIRA MAMBRINI
  • Data: 18-nov-2022

  • Resumen Espectáculo
  • Membrane separation processes (PSM) are classified as a promising technology due to their technical and economic viability. PSM present inherent limitations to the separation process due to concentration polarization and scale formation on the membrane surface. Aiming to minimize these limitations and increase their separation performance, the development of hybrid membranes has been observed, through the incorporation of inorganic particles in the polymer matrix of the membrane. Due to their eccentric characteristics, metalorganic networks (MOFs), a class of porous materials, have been widely used in the production of hybrid membranes improving the separation properties. Given the above, the present work aims to synthesize hybrid membranes containing a polymeric matrix consisting of polyetherimide (PEI) impregnated with MOF based on the ligand 1,4-benzenedicarboxylate (bdc) and Cu(II). The hybrid membranes obtained were characterized by X-ray diffraction (XRD), infrared absorption spectroscopy (FTIR), thermogravimetric analysis (TG), and by scanning electron microscopy (SEM). Hybrid membranes were analyzed for hydrophobicity by measuring contact angles, stability against an oxidizing environment, porosity measurements and their performance regarding the permeation flux. The membranes were submitted to an oxidation test to investigate their activity as catalysts activating H2O2 in the removal of the blue of methylene. Hybrid membranes showed a higher percentage of removal when compared to membranes containing only PEI, evidencing its catalytic activity. In addition to indicating a high dispersion of MOFCu in the polymeric matrix, this being a point important in the synthesis of hybrid membranes. The hybrid membrane with the highest content of MOFCu showed a more pronounced hydrophilic character and greater hydraulic permeability. Therefore, incorporating MOF into the polymeric matrix had positive results for the synthesis of hybrid membranes.

10
  • SABRINA PETRILLO SAMPAIO
  • Biomateriai production using fungi and agrcultural waste 

  • Líder : FERNANDA BADOTTI
  • MIEMBROS DE LA BANCA :
  • FERNANDA BADOTTI
  • ANGELA DE MELLO FERREIRA
  • ANDREA RODRIGUES MARQUES
  • ARISTOTELES GOES-NETO
  • Data: 29-nov-2022

  • Resumen Espectáculo
  • Materials derived from petroleum are used for the most diverse applications, however the process of deterioration or decomposition of most of these materials is slow which results in a major environmental problem A promising alternative to replace petroleum derivatives are biomaterials produced from fungal mycelia grown on plant residues (biocomposites) that are completely biodegradable and have the potential to generate materials with diverse mechanical properties. This project aims to evaluate the mechanical properties of mycocomposites produced with sugarcane bagasse residues and the cultivation of fungi of the species Trametes villosa and Ganoderma lucidum. Specifically, density, compressive strength, water absorption and thermogravimetric analysis are analyzed. In addition, we analyzed the influence of adding mining tailings to culture media. The results obtained for density ranged from 74.5 kg/m³ to 220.62 kg/m³. The thermogravimetric analysis showed an initial degradation temperature of ± 250 ° C, in relation to water absorption the analysis showed a non-linear behavior of the water absorption curve, explained by the hydrophobic nature of the mycelium and the hydrophilic nature of the fibers.

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