Trabalhos de Conclusão de Curso - Itapeva

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Cálculos de estrutura eletrônica aplicados ao estudo de sensores químicos baseados em polímeros: derivados de politiofeno
(Universidade Estadual Paulista (Unesp), 2018-11-28) Pinheiro, Marcos Geovanni de Souza [UNESP]; Batagin Neto, Augusto [UNESP]; Universidade Estadual Paulista (Unesp)
Polymeric materials are promising candidates for the manufacture of chemical sensors mainly due to their high versatility of synthesis and low relative cost. In this context, polythiophene derivatives have been considered quite interesting materials. In order to better understand the sensory properties of these materials and propose derivatives with improved features, in the present work electronic structure calculations were carried out to evaluate local reactivities and adsorption processes of gaseous molecules on the structure of polythiophene modified derivatives. The reactivity data were evaluated via Condensed-to-atoms Fukui Indexes by two distinct approaches. From these results, adsorption studies were conducted in two steps. The influence of the chemical species was evaluated and discussed in terms of structural features, energy levels distributions, changes on the optical absorptions, and binding energies. The obtained results indicate the derivative P3HT-Cl as the most promising material for application in the active layer of chemical sensors. In addition, the results also indicate that the presence of reactive side groups can guide and intensify the interaction of the polymers with analytes and avoid their chemical degradation
Caracterização físico-mecânica de painéis OSB submetidos a tratamento térmico em estufa
(Universidade Estadual Paulista (Unesp), 2018-11-23) Santos, Diego Veiga [UNESP]; Campos, Cristiane Inácio de [UNESP]; Universidade Estadual Paulista (Unesp)
The OSB panel is formed by strands arranged in three layers, with the extern parallel and in the interior perpendicular to the anterior layer. By using Pinus Teada and polyurethane resin based on castor oil, the OSB panels were produced and the main objective of this study was to compare the effect of thermal rectification with four different treatments, without the use of thermal rectificationn, thermal rectification 160, 180 and 200o C. It was possible to observe that among the treatments performed T3, with thermal rectification temperature of 180oC, was the one that presented the best class of resistance for the physical properties and smaller reduction of the mechanical properties against the treatment T1 and even with values found in the literature. It also presented a better performance of the panels in contact with water, proving suitable for thermal rectification
Desempenho físico-mecânico de painéis OSB submetidos a tratamento químico com CCA
(Universidade Estadual Paulista (Unesp), 2018-11-26) Santos, Felipe Antonio dos [UNESP]; Campos, Cristiane Inácio de [UNESP]; Universidade Estadual Paulista (Unesp)
The increasing use of wood-base panels some studies have been carried out with the purpose of the best use and improvement of their properties. As well as the rational use of the raw material. Therefore, the objective of this study was to determine the chemical treatment with CCA in OSB panels of pinus and to analyze the influence of the treatment on physical properties such as density, moisture content, swelling and absorption, and mechanical properties such as resistance to static flexion and internal adhesion of the panels. The panels were produced using the melamine-formaldehyde resin with the distribution of the 20% particles at their ends and 60% at the center of the panel. The panels have been characterized according to European standards. The treated panels obtained higher moisture content and lower thickness swelling. Untreated panels meet the requirements for Class 1 OSB panels for internal and non-structural use, as the treated panels have not reached the required minimums for any class
Caracterização anatômica do lenho de Syzygium cumini
(Universidade Estadual Paulista (Unesp), 2017-06-22) Rodrigues, Vanessa Monteiro de Oliveira [UNESP]; Barreiros, Ricardo Marques [UNESP]; Universidade Estadual Paulista (Unesp)
This research is to characterize the anatomy of the species Syzygium cumini (Jambolão), as well as to describe and analyze its anatomical elements, such as: size, vessel diameter and ray parenchyma types according to the IAWA (1989), Through investigations carried out, possible through observation in the Microscope (Leica) and assemble the slides using the modified method described by Franklin (1945). Academic support and research material were provided by Unesp Campus of Itapeva. The tree of Syzygium cumini, also known as Jambolão, was collected in the municipality of Itapeva (SP) in the Institution itself. In addition, studies were carried out to estimate tree age, a macroscopic stem analysis, as described by Copant (1973) and Ceccantini and Zenid (2000). The species presented age of 20 years, with density of 0.632 g / cm³ and fibers with dimensions of 1742.94 μm, mean lumen of 10.88 μm and cell wall 8.17 μm. It has a paratracheal axial parenchyma in bands with predominant solitary vessels, with a mean diameter of 108 μm, with few vessels and 8 vessels / mm². In the tangential section, it contains multisseries rays with high cell variability, ranging from 11 to 60 cells per radius, also presents uniseriate rays in a smaller amount, they present height with a mean of 625.24 μm and a fine width of 45.89 µm
Análise do método proposto pela ABNT NBR 7190:1997 para determinação do valor característico à tração normal às fibras para madeiras de reflorestamento da região de Itapeva
(Universidade Estadual Paulista (Unesp), 2018-11-26) Leite, Murilo Augusto Veríssimo [UNESP]; Molina, Julio Cesar [UNESP]; Universidade Estadual Paulista (Unesp)
The application of the characteristic value in the civil sector has been providing promising results in relation to safety concepts in projects, especially in the sizing. The characteristic value is obtained through the probabilistic method and by the centered estimator method, described in ABNT NBR 7190 (1997). The condition for using these methods is to assume of samples with a normal probability distribution. This work had analyze the normality of the data in the results obtained from mechanical tests of normal traction to the fibers, as well as to verify the size of sample to meet the requirements of normality, in addition to comparing the characteristic value by the probabilistic method and centered estimator and the coefficient of eccentricity of the centered estimator equation. To carry out this work reforested wood was used in the region of Itapeva-SP (Eucalyptus Grandis and Pinus E lliottii). Test specimens of normal traction were made to the fibers mechanical tests as recommended. resistance, a simulation was performed by the Bootstrap method with the aid of the software R, to verify the normality of the data, with the Shapiro Wilk test. To eucalyptus from 30 samples, a normal probability distribution was obtained and for the pinus 42 samples. The coefficient of eccentricity that best fit for the species of eucalyptus was 1,00 and for pine species 1,10
Caracterização microestrutural da superliga Inconel 625 no estado bruto de fusão e após tratamentos térmicos de solubilização e envelhecimento
(Universidade Estadual Paulista (Unesp), 2018-11-23) Tanno, Tiemi Manfio [UNESP]; Baldan, Renato [UNESP]; Universidade Estadual Paulista (Unesp)
The superalloys are a group of materials developed for applications that requires high mechanical and corrosion/oxidation resistance at high temperatures. Nowadays, Inconel 625 is the most utilized nickel-based superalloy applied in gas turbines, marine equipment and heat exchanger. Despite this alloy have been developed to be applied in the as-cast state, the precipitation of intermetallic phases and carbides when the alloy is submitted to heat-treatments between 1100 e 1300ºC changes the microstructure and, consequently, the properties of the material. Based on this, the aim of this work were to evaluate and correlate the microstructure (through optical/electronic microscopy and differential thermal analysis techniques) and mechanical property (through hardness tests) of Inconel 625 nickel-based superalloy in the as-cast state and after heat-treatments at different conditions of time and temperature. The thermodynamic simulations with JMatPro (nickel database) were performed to define the heat-treatment conditions. The results of the microstructural characterization (as-cast and heat-treated samples) and the hardness measurements were compared with JMatPro simulations in order to validate the results and the software database. The results allowed understanding the microstructural and mechanical changes that occurs in the Inconel 625 superalloy during the heattreatments. The results were compared with JMatPro simulations in order to validate the experimental results and the program database. The simulations allowed extrapolate the results for real service conditions and evaluate the behavior of the material at high temperatures for long times, condition which is many times inviable in laboratorial scale. In the as-cast and solubilized samples, it was possible to observe the grains, the grain boundaries and the presence of pores and carbides. In the aged samples, it was observed a tendency to increase grain size with increasing time and...
Torrefação do bagaço de cana-de-açucar para fins energéticos
(Universidade Estadual Paulista (Unesp), 2018-11-30) Melles, Victor [UNESP]; Luna, Carlos Manuel Romero [UNESP]; Universidade Estadual Paulista (Unesp)
Bagasse and straw are residues from the industrial processing of sugarcane that constitute an important source for cogeneration of energy in the sugar-alcohol sector, but the bagasse presents properties as a high moisture content, low density and low energy density, resulting in a low energy efficiency of the biomass and loss of materials due to deterioration. One of the alternatives for improving these properties is the application of the torrefaction process, which consists of a thermal pretreatment of biomass in that the raw biomass is heated in an inert atmosphere at temperatures of 200 to 300 ° C. The torrefaction process allows the conversion of raw biomass into solid fuel suitable for combustion and gasification. Torrified biomass has better properties, such as higher energy density, lower hydrophilic nature, lower ratio of O / C and H / C atoms, and greater ease of storage and transport. In this work, it is proposed to conduct thermal studies to evaluate the applicability of the torrefaction process in the residual sugarcane bagasse in a sugar-alcohol industry. The experiments were run at 200 and 300 °C for 30 and 60 minutes. In order to verify the effect of the roasting process on the thermal characteristics of the bagasse, the results of the higher heating value (HHV) were analyzed, which allow to evaluate the energetic gain in the torrified bagasse, and the results of the thermogravimetric tests that determine the conversion rates and the reaction rate coefficients. The torrified BCA showed an increase in HHV, reduction of moisture content and reduction of material volume in all cases
Estudo sobre a avaliação da qualidade de shapes de skates e o desenvolvimento de metodologias para caracterização física e mecânica
(Universidade Estadual Paulista (Unesp), 2018-11-20) Marangon, Rodrigo de Mata [UNESP]; Morais, César Augusto de Galvão [UNESP]; Universidade Estadual Paulista (Unesp)
Since the creation of skateboarding in the 1950s, it has been possible to observe the growth of skateboarding as a sport, from a recreational practice to Olympic sport status. This evidences the significant increase in the number of practitioners of this sport and the development of applied science in the area. A fundamental part of the skateboard, the deck is a laminated plywood board where the axles that receive the wheels are fixed, this product suffers damages due to the efforts undergone during the practice of the sport. The evaluation of the quality and characteristics of the skateboard are important to guarantee and ensure the quality of the products and the practice of the sport, as well as the safety of the practitioners. For the analysis of the physical and mechanical characteristics, six different types of tests were performed, in ten types of commercial decks, all with different combinations of wood, adhesive and reinforcement, two of them specially developed for this work. In this context, tests were carried out to determine the specific mass, determination of the moisture content, determination of bonding quality, determination of resistance to static bending, determination of the resistance to static bending in real scale and analysis of energy absorption, being the last two new methodologies. At the end, the results of each of the steps were analyzed and the deck types were ranked based on values of relevance for each measured variable. It was concluded the importance of the use of glass fiber reinforcement and epoxy adhesive to increase mechanical strength, however, it must be taken into account the increase in its specific mass. After finishing the ranking, one of the lines formed by Acer saccharum sheets and epoxy adhesive showed the best performance of the analyzed variables. With clearer information about the characteristics of the deck configurations, it is expected that the companies can have a better orientation regarding...
Estudo experimental da lixiviação da escória de FeSiMn
(Universidade Estadual Paulista (Unesp), 2018-11-29) Cuba, João Pedro Barros [UNESP]; Luna, Carlos Manuel Romero [UNESP]; Universidade Estadual Paulista (Unesp)
Ferro-Manganese (FeMn) alloys industry produces important raw materials for steelmaking, which are High Carbon Ferro-Manganese (HC FeMn) and Ferro-SiliconManganese (FeSiMn). However, production process generates several types of solid waste, being the most important the FeSiMn slag. Many researches have been conducted aiming at the utilization of FeSiMn slag in cement production, but few works aiming the extraction of added value elements by leaching process. Thus, in this work, the leaching of FeSiMn slag was studied in order to extract elements of interest. For this purpose, FeSiMn slag was donated by Maringá Ferro-Ligas. FeSiMn slag passed through crushing and milling processes, physical and chemical characterization tests, particle size analysis, x-ray diffraction analysis and x-ray fluorescence were performed. A parametric study of leaching with HCl solutions at three distinct concentrations and temperature ranges respectively, was carried out, in order to analyze the effects of concentration and temperature. The time of reaction and the solid: liquid (S:L) ratio used were maintained constant. The results show different characteristics for each condition analyzed, in some cases two solid phases were obtained, in others a colloid. The solid phases were characterized using x-ray diffraction and x-ray fluorescence. Finally, the yield of the process with respect to the elements of greatest interest (Mn, Si, Ca and Al) was calculated. In this work, the leaching test that presented the best result was the one performed using 1 molar of HCl and temperature of 95°C. In this test the final mass concentration of SiO2 was 68.40%, and the yield of the process was 59%
Análise da potencialidade de geração de energia elétrica a partir do biogás de aterro sanitário na cidade de Itapeva/SP
(Universidade Estadual Paulista (Unesp), 2018-11-30) Rossini, Matheus Henrique [UNESP]; Luna, Carlos Manuel Romero [UNESP]; Universidade Estadual Paulista (Unesp)
The increase in population and in consumption of goods and services, stimulated by technological innovations, directly influences on generation of municipal solid waste (MSW) and the use of resources for generating energy, increasing greenhouse gas emissions, as well as other problems associated with MSW. Even with the establishment of the National Policy on Solid Waste, the disposal of MSW is classified as inadequate according to CETESB, not only in Itapeva/SP but in most of the municipalities in Brazil. Thus, the study consisted in applying USEPA's (1998 and 2005) and World Bank (Scholl Canyon) biogas generation models to estimate the methane production from Itapeva/SP MSW. The input parameters were the same for each model. The values obtained for the methane generation potential (L0) and for the methane (k) generation rate were 99.33 m3CH4 / ton. RSU and 0.06, respectively. It was considered 9 different cases in relation to the time of reception of residues in the landfill and the increase in the MSW generation rate. For each of the 9 cases, the total production of CH4 (m3), the average amount of electric energy available per year and the percentage of Itapeva's population that could benefit from such energy were obtained. For the more conservative case (case 1), it would be possible to benefit 0.46% of the population, while 1.55% would benefit from the more optimistic forecast (case 9). In addition, special cases were applied to obtain the amount of RSU needed to benefit 50% of the population. Finally, the portion of the benefited population was obtained in each of the initial cases, considering the RSU generation rate as being the sum of Itapeva's and some of the neighboring munipalities' RSU generation rate. In this case, the amount of available energy and the share of the beneficiary population were increased. Although some assumptions were conservative and can be better refined, the results...
Avaliação da qualidade de colagem de elementos de MLC confeccionados com madeiras de eucalipto e resina fenólica
(Universidade Estadual Paulista (Unesp), 2018-11-26) Páschoa, Douglas Pontes [UNESP]; Molina, Julio Cesar [UNESP]; Universidade Estadual Paulista (Unesp)
To increase the wood solutions, the country has adopted new construction techniques, which use wood by-products, among which can be cited Laminated Wood (MLC). The present work consisted in evaluating the proposed standard ABNT NBR PN 02: 126.10- 001-5, putting in practice the glued laminated wood elements with respect to the tests of shear strength and delamination of the glue line for wood of Eucalyptus, obtained by means of reforestation of the region of Itapeva-SP. In the mechanical characterization of the wood, they were subjected to compression tests parallel to the fibers, parallel shear to the fibers and static bending. The confection of glued laminated wood was accomplished through the application of the resorcinol formaldehyde resin to the glueing of the lamellae of wood. All of them were classified mechanically and visually. The tests were carried out, evaluating the quality of bonding of the resin to the wood. In the delamination of the glue line an autoclave was constructed, built specifically for this test. The other tests were performed in the universal test machine (EMIC) with a capacity of 300 kN, available at the Material Properties Laboratory of UNESP of Itapeva-SP. Glue bonding was not satisfactory, with maximum percentages of glue line delamination of 71.40 %. The average shear strength of the glue lines - considering the same MLC element - did not show significant differences between them
Projeto de uma turbina eólica de eixo vertical em bambu
(Universidade Estadual Paulista (Unesp), 2018-11-28) Campos, Bruno Dueñas Proença de [UNESP]; Amasifen, Juan Carlos Cebrian [UNESP]; Universidade Estadual Paulista (Unesp)
Nowadays Brazil's energy matrix is mainly composed of renewable sources. Although the matrix is diversified, it basically depends on hydropower plants which are highly dependent on the capacity of the water reservoirs. In current climate change scenarios, reservoirs are affected by constant drought, which reduces the capacity to generate electricity. One way to meet the demand for energy is to use alternative sources such as photovoltaic and wind power. In this sense, the use of wind as an alternative source is increasingly growing and gaining space in the national and world scenario, mainly by the use of wind turbines that allow the transformation of wind power into electric power. These equipment are widely used in wind farms installed in extensive geographic areas with relatively high wind speeds. In addition, Vertical Axis Wind Turbines (TEEV) have gained space in the transformation of energy basically by the ability to obtain electrical energy in residential, commercial and urban areas with lower wind speeds and wind speeds, so TEEVs can be easily implemented in several environments, ranging from an urban building to an open field. In this context, this project develops and analyzes the feasibility of using a vertical-axis wind turbine, manufactured using bamboo, in order to obtain a final product that provides satisfactory results, using a natural and sustainable raw material, with a long lifespan, and more simplified forming process, without the need for robust equipment. The results show that bamboo has great potential to be considered as an alternative material for manufacturing blades of TEEVs
Análise do potencial biodegradativo da levedura Saccharomyces cerevisiae na remoção de corantes têxteis e efluente coletado de uma lavanderia industrial têxtil: um estudo da biorremediação
(Universidade Estadual Paulista (Unesp), 2018-11-22) Ercolini, Sofia Tafuri [UNESP]; Goveia, Danielle [UNESP]; Universidade Estadual Paulista (Unesp)
Technological innovation in the textile industrial area has contributed positively to the world economy, however, this innovation generates impacts to the environment due to the large production of industrial waste that is often discarded in the water bodies without adequate treatment. These pollutants from the textile industry are characterized by high coloration and difficult degradation, thus, the waste generated by the textile industry has become a major concern in terms of pollution of water resources and the alteration of their ecosystem. Among the existing treatments, bioremediation is emerging as an object of research in several areas. It is a methodology that fits the principles of Green Chemistry, since it aims at the design of microorganisms that degrade toxic substances in innocuous forms. Saccharomyces cerevisiae yeast is an optional aerobic microorganism that has the ability to adapt metabolically under aerobic or anaerobic conditions while maintaining its high growth rate. The objective of this study was to analyze the biodegradable potential of yeast Saccharomyces cerevisiae in the removal of textile dyes by the spectrophotometric analysis of molecular absorption in the visible ultraviolet region. For the best evaluation of the biodegradable potential of the yeast Saccharomyces cerevisiae, the orange and methyl indigo carmine dyes were used in this work and then applied in industrial laundry effluent. The results indicate that the yeast is capable of biodegrading both dyes. However, it showed a higher biodegradability when exposed to the indigo dye solution, reducing its coloration by 53%. In addition, the suspension was able to biodegrade the textile effluent throughout the reaction period. The yeast was able to reduce the initial effluent concentration by up to 87%, thus, bioremediation through the use of yeast Saccharomyces cerevisiae proved to be effective for the treatment of wastewater from textile laundries
Avaliação da influência da variação da geometria de peças de madeira Pinus elliottii na frequência e rigidez por métodos não destrutivos de ensaio
(Universidade Estadual Paulista (Unesp), 2018-06-28) Silva, Vitor Afonso Neves [UNESP]; Morales, Elen Aparecida Martines [UNESP]; Universidade Estadual Paulista (Unesp)
The study of the mechanical characterization of wood is of fundamental importance for a more efficient use of reforestation species in structures, compared to other materials and the properties are widely known, especially in a time when wood is a sustainable practice. The Impulse Excitation Technique (TEI) is a type of nondestructive test where the impact force is induced by an acoustic sequence through natural frequencies of vibration, from which the dynamic modulus of elasticity can be constructed the handheld to success in the modula of elasticity in the static bending to the wood. This work has the general objective of evaluating the influence of the variation in the dimensions of pieces of wood of Pinus elliottii in parameters of the non destructive method of impulse excitation test, for the pre-classification of the same ones for use in structures. It was concluded that, for the samples of Pinus elliottii used, the length interferes significantly in the frequency obtained, which does not occur with the widths. For the test specimens of 115 x 5.0 x 5.0 cm the dynamic elastic moduli (Ed), obtained by the impulse excitation test, did not differ statistically from those obtained by the destructive static bending test (EM), which also occurred with the dynamic elastic moduli (Ed) related to the test specimens of 45 x 5.0 x 2.5 cm in relation to the modulus of elasticity in the traction parallel to the fibers (Et0), demonstrating the effectiveness of TEI in evaluation of the pieces of Pinus elliottii used
Caracterização de resíduos de poda, amostragem de poluentes advindos de sua queima e eficiência de combustão
(Universidade Estadual Paulista (Unesp), 2018-06-11) Neves, Vanessa Ferreira [UNESP]; Cieslinski, Juliana Esteves Fernandes [UNESP]; Universidade Estadual Paulista (Unesp)
As urban pruning waste is almost entirely destined for landfills along with all other wastes, there is an environmental concern with the possible products coming from the contact between them and with the early termination of the life of the landfill due to large spaces occupied by bulky pruning waste. A satisfactory and environmentally acceptable solution for such waste would be the use as a fuel, i.e. for energy purposes. This project, therefore, had as objective to characterize the pruning residue for later use as biomass fuel in direct burning. The chemical characterization of the pruning residues obtained at the Itapeva Experimental Campus (UNESP) was carried out by means of the immediate chemical analysis with the determination of the average moisture content (12.03%), to characterize these characteristics. its direct relation with the calorific value of biomass (PCS); (71.11%), a fraction that expresses the ease of ignition and burning of the fuel and greatly influences the gaseous flow profile in the furnace and the chemical reaction rate, that is, it plays an important role in the initial stages of combustion of biomass; of the ash content (5.71%), which shows the residues coming from the combustion of the organic components and oxidation of the inorganics and can negatively influence the PCS. By calculation, the fixed carbon content (23.18%) was determined, which is the remaining mass after the release of the volatile compounds excluding the ash and the moisture content. In addition to the chemical characterization, it is necessary to characterize the energy of a fuel and, with that, the residues in question were analyzed in calorimeter to obtain the superior calorific value (PCS). The mean value found was 17013 J / g (to the moisture content of approximately 16%). Sequentially, the chemical analysis of the cell wall of the biomass was carried out as extractive content (13.80%), lignin content (36.27%), and holocellulose content...
Produção de biocombustíveis a partir da pirólise lenta do bagaço de cana-de-açúcar
(Universidade Estadual Paulista (Unesp), 2018-01-30) Vieira, Samuel Faria [UNESP]; Luna, Carlos Manuel Romero [UNESP]; Universidade Estadual Paulista (Unesp)
This work aims to obtain biofuels, biochar and bio-oil through the process of slow pyrolysis of sugarcane bagasse. In this work the effect of different temperatures (300, 400 and 500 ° C) on the biochar and bio-oil yield, as well as some properties, was evaluated. For the experimental tests the heating rate, particle size (250-500 μm) and a constant flow of entrainment gas were kept constant. The physico-chemical and energetic characterization of the products of the slow pyrolysis were carried out by different methods, such as immediate, compositional, pH and high calorific value (PCS) analysis. The results showed that the maximum yield of the bio-oil (52%) was obtained at 300øC, pH 3.5 and a PCS of 10.45 MJ / kg. Biochar yielded a yield of 34% at 300øC, pH 8.1 and PCS of 28.23 MJ / kg. The results show that the higher the temperature, the lower the amount of the solid fraction (biochar), the temperature did not influence significantly the PCS of the biofuels and that the reactivity of the biochar is higher in lower temperatures. It is believed that the physico-chemical properties, as well as the origin of matter and its process, directly influence the quality of biofuels. Several applications can be approached for these products, however, much is discussed regarding bio-oil as a complement to fuels and biochar in the generation of energy, increasing the share of renewable energy in the Brazilian energy matrix
Estudo da reatividade de subestruturas de lignina via cálculos de estrutura eletrônicas
(Universidade Estadual Paulista (Unesp), 2018-06-15) Maia, Rosangela Almeida [UNESP]; Batagin Neto, Augusto [UNESP]; Universidade Estadual Paulista (Unesp)
Lignin is one of the most abundant natural material around the world, accounting for about a quarter of the woody tissue composition of plants. In general it is well known that these highly branched aromatic biopolymers are formed from the polymerization of p-coumarol, coniferol and sinapol alcohols, however the structural connection between these structures is still not known in detail. In this work, we have employed electronic structure calculations to investigate local reactivities and details about the connectivity between the basic subunits of lignins. Condensed-to-atoms Fukui indexes, local softness and hard and soft acids and bases principle were employed in the analyses. The results allow to identify reactive regions on the monomer and dimer structures, that allows to propose routes of lignin polymerization/degradation from these reduced structures
Caracterização química e estudo dos efeitos das variáveis de polpação kraft e soda do línter de algodão
(Universidade Estadual Paulista (Unesp), 2017-11) Rodrigues, Claudinei Henrique Ferreira [UNESP]; Caraschi, José Cláudio [UNESP]; Universidade Estadual Paulista (Unesp)
Cotton linter is currently a by-product of the cotton industry, the fiber being closest to cotton seed. Failure to remove this fiber can cause problems, especially in machines that redo planting seeds in the field and can clog the nozzles from which the seeds emerge. The use of this linter can be a revolution in the cotton agroindustry, since it is currently seen as an agent that ends up disrupting the process. In search of new sources of raw material for the production of pulp, the industry invests every year in research in this sector. The variables of pulping, be they kraft or soda, are very important to know the ideal conditions to obtain a raw material of good quality, and with a good yield, with a great financial return. The degree of polymerization of the cellulose is one of the main factors to be analyzed when it is desired to prepare pulp for dissolution. The conditions analyzed in this study were of active alkali varying between 10%, 12%, 14% and 16% for the soda and kraft pulp, with the difference only in sulphidity for kraft pulping, alternating between 15% and 25%, all in percentage volume of solution per volume of cooking liquor. The pulping conditions were kept unchanged at 160 ° C maximum temperature, 60-minute digester heating ramp and baking for 90 minutes, all in a 5:1 ratio of liquor:linter. The results were satisfactory due to the self-degree of polymerization of the cotton pulp cellulose, especially the sulphide kraft pulps up to 15%, where the degree of polymerization increased as the active alkali was increased
Modelagem de uma lâmina de serra de fita submetida a força de corte paralela
(Universidade Estadual Paulista (Unesp), 2018-06-20) Machado, Elder Jesus Lima [UNESP]; Bôas, Daniel Villas [UNESP]; Souza, Alexandre Jorge Duarte de [UNESP]; Universidade Estadual Paulista (Unesp)
Used in the unfolding of wood logs the band saw blade undergoes several types of cyclic stresses that can cause fatigue damage. Among these efforts are the shear forces, which are essential for the correct sizing of the machine. The present work aims to analyze the influence of the parallel shear force on the longitudinal normal stress (σy). For this purpose, two models were constructed use the Finite Element Method (MEF) use commercial software ABAQUS® 6.14. The results indicated an increase in tensile stress along the blade, especially in the region near the bottom of the tooth, but not enough to cause any damage to the tool
Estudo térmico da combustão de biomassa
(Universidade Estadual Paulista (Unesp), 2017-11-21) Macedo, Lucas Carvalho Novaes de [UNESP]; Cieslinski, Juliana Esteves Fernandes [UNESP]; Universidade Estadual Paulista (Unesp)
The Brazilian energy matrix has been going through a change, where it occurs a decrease in energetic supply by the non-renewable fuels inducing an increase in renewable fuels supply. Therefore, the biomass is a clean and flexible source of energy. With the expansion of Brazilian agricultural production due to the amount of arable land, studies point out a perspective on agricultural production growth, consequently, an increase in biomass production in this country. For that reason, this work aimed to analyses the energy aspects of biomass, determining the superior and inferior calorific value, experimentally and through calculations. To the experimental determination of SCP, it was used the calorimeter C 5000 Control Package 1/12. The experimental results showed that the studied biomass, rice husk, sugarcane bagasse and corn straw, brought up an SCP of 14,16 MJ/kg, 16,71 MJ/kg and 16,92 MJ/kg, respectively

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