Envelhecimento ambiental em compósitos poliméricos à base de tecidos de reforços híbridos

The utilization of synthetic fibers for plastic reinforcement is more and more frequent and this growing interest requires that their mechanic behavior under the most variable conditions of structural applications be known. The use of such materials in the open and exposed to the elements is one of them. In this case, it becomes extremely necessary to study their mechanical properties (strength, stiffness) and the mechanism of fracture by which the environment aging them out. In order to do that, the material must be submitted to hot steam and ultraviolet radiation exposure cycles, according to periods of time determined by the norms. This study proposal deals with the investigation of accelerated environmental aging in two laminated polymeric composites reinforced by hybrid woven made up of synthetic fibers. The configurations of the laminated composites are defined as: one laminate reinforced with hybrid woven of glass fibers/E and Kevlar fibers/49 (LHVK) and the other laminate is reinforced with hybrid tissue of glass fibers/E and of carbon fibers AS4 (LHVC). The woven are plane and bidirectional. Both laminates are impregnated with a thermofix resin called Derakane 470-300 Epoxy Vinyl-Ester and they form a total of four layers. The laminates were industrially manufactured and were made through the process of hand-lay-up. Comparative analyses were carried out between their mechanical properties by submitting specimen to uniaxial loading tractions and three-point flexion. The specimen were tested both from their original state, that is, without being environmentally aging out, and after environmental aging. This last state was reached by using the environmental aging chamber

Avaliação mecânica e microestrutural de compósitos de poliéster com adição de cargas minerais e resíduos industriais

With the current growth in consumption of industrialized products and the resulting increase in garbage production, their adequate disposal has become one of the greatest challenges of modern society. The use of industrial solid residues as fillers in composite materials is an idea that emerges aiming at investigating alternatives for reusing these residues, and, at the same time, developing materials with superior properties. In this work, the influence of the addition of sand, diatomite, and industrial residues of polyester and EVA (ethylene vinyl acetate), on the mechanical properties of polymer matrix composites, was studied. The main objective was to evaluate the mechanical properties of the materials with the addition of recycled residue fillers, and compare to those of the pure polyester resin. Composite specimens were fabricated and tested for the evaluation of the flexural properties and Charpy impact resistance. After the mechanical tests, the fracture surface of the specimens was analyzed by scanning electron microscopy (SEM). The results indicate that some of the composites with fillers presented greater Young s modulus than the pure resin; in particular composites made with sand and diatomite, where the increase in modulus was about 168 %. The composites with polyester and EVA presented Young s modulus lower than the resin. Both strength and maximum strain were reduced when fillers were added. The impact resistance was reduced in all composites with fillers when compared to the pure resin, with the exception of the composites with EVA, where an increase of about 6 % was observed. Based on the mechanical tests, microscopy analyses and the compatibility of fillers with the polyester resin, the use of industrial solid residues in composites may be viable, considering that for each type of filler there will be a specific application

Desenvolvimento e avaliação de padrão de torque para calibração de torquímetros em três faixas de medição

The continuous development of instruments and equipment used as tools or torque measurement in the industry is demanding more accurate techniques in the use of this kind instrumentation, including development of metrological characteristics in torque measurement. The same happens with the needs in calibration services. There is a diversity of methods of hand torque tools in the market with different measuring range but without complaining with technical standards in terms of requirements of quality and reliability. However, actually there is no choice of a torque measuring standard that fulfils, with low cost, the needs for the calibration of hand torque tools in a large number of ranges. The objective of this thesis is to show the development and evaluation of a torque measuring standard device with a conception to allow the calibration of hand torque tools with three levels of torque with an single instrument, promoting reduction of costs and time in the calibration, also offering reliability for the evaluation of torque measuring instrument. To attend the demand in the calibration of hand torque tools it is necessary that the calibration laboratories have a big collection of torque measuring standards, to fulfills the needs of the costumer, what is very costly. The development of this type of torque measuring standard revealed a viable technique and economically making possible the calibration of hand torque tools in different nominal ranges through a single measurement system versatile, efficient and of easy operation

Estudo da incorporação de resíduo industrial polimérico ao CAP

This work presents the incorporation of an industrial polymeric waste into a petroleum asphalt cement with penetration grade 50-60 (CAP 50-60). The main goal of this research is the development of a polymer-modified asphalt, with improvements in its physical properties, in order to obtain a more resistant material to the traffic loads. Furthermore, the use of this polymeric waste will result in economic and environmental benefits. The CAP 50-60 used in this research was kindly supplied by LUBNOR Lubrificantes e Derivados de Petróleo do Nordeste (produced in Fazenda Belém Aracati - Ceará) and the industrial polymeric waste was provided by a button manufacturer industry, located in Rio Grande do Norte state. This polymeric waste represents an environmental problem due to its difficulty in recycling and disposal, being necessary the payment by the industry to a landfill. The difficulty in its reuse is for being this material a termofixed polymer, as a result, the button chips resulting from the molding process cannot be employed for the same purpose. The first step in this research was the characterization of the polymeric waste, using Differential Scanning Calorimetry (DSC) Infrared spectroscopy (IR spectroscopy), and Thermogravimetric analysis (TGA). Based on the results, the material was classified as unsaturated polyester. After, laboratory experiments were accomplished seeking to incorporate the polymeric waste into the asphalt binder according to a 23 experimental factorial design, using as main factors: the polymer content (2%, 7% and 14%), the temperature of the mixture (140 and 180 oC) and the reaction time (20 and 60 minutes). The characterization of the polymer-modified asphalt was accomplished by traditional tests, such as: penetration, ring and ball softening point, viscosity, ductility and flash point temperature. The obtained results demonstrated that the addition of the polymeric waste into the asphalt binder modified some of its physical properties. However, this addition can be considered as a feasible alternative for the use of the polymeric waste, which is a serious environmental and technological problem.

Desenvolvimento de um reator fotoquímico aplicável no tratamento de efluentes fenólicos presentes na indústria do petróleo

With water pollution increment at the last years, so many progresses in researches about treatment of contaminated waters have been developed. In wastewaters containing highly toxic organic compounds, which the biological treatment cannot be applied, the Advanced Oxidation Processes (AOP) is an alternative for degradation of nonbiodegradable and toxic organic substances, because theses processes are generation of hydroxyl radical based on, a highly reactivate substance, with ability to degradate practically all classes of organic compounds. In general, the AOP request use of special ultraviolet (UV) lamps into the reactors. These lamps present a high electric power demand, consisting one of the largest problems for the application of these processes in industrial scale. This work involves the development of a new photochemistry reactor composed of 12 low cost black light fluorescent lamps (SYLVANIA, black light, 40 W) as UV radiation source. The studied process was the photo-Fenton system, a combination of ferrous ions, hydrogen peroxide, and UV radiation, it has been employed for the degradation of a synthetic wastewater containing phenol as pollutant model, one of the main pollutants in the petroleum industry. Preliminary experiments were carrier on to estimate operational conditions of the reactor, besides the effects of the intensity of radiation source and lamp distribution into the reactor. Samples were collected during the experiments and analyzed for determining to dissolved organic carbon (DOC) content, using a TOC analyzer Shimadzu 5000A. The High Performance Liquid Chromatography (HPLC) was also used for identification of the cathecol and hydroquinone formed during the degradation process of the phenol. The actinometry indicated 9,06⋅1018 foton⋅s-1 of photons flow, for 12 actived lamps. A factorial experimental design was elaborated which it was possible to evaluate the influence of the reactants concentration (Fe2+ and H2O2) and to determine the most favorable experimental conditions ([Fe2+] = 1,6 mM and [H2O2] = 150,5 mM). It was verified the increase of ferrous ions concentration is favorable to process until reaching a limit when the increase of ferrous ions presents a negative effect. The H2O2 exhibited a positive effect, however, in high concentrations, reaching a maximum ratio degradation. The mathematical modeling of the process was accomplished using the artificial neural network technique

Secagem do resíduo industrial da acerola em leito de jorro: estudos fluidodinâmicos e análise do desempenho do secador

In this research, the drying process of acerola waste was investigated by using a spouted bed drier. The process was conducted using high density polyethylene inert particles with the objective of producing an ascorbic acid-rich final product. The fruit waste was ground and used to prepare different water-maltodextrin suspensions. Initially, fluidynamical experiments were conducted in order to evaluate the feeding effect on the spouted bed drier fluidynamics behavior. The experimental planning 23 + 3 was used to investigate the effect of the following variables: solids concentration, drying air temperature, intermittence time, production efficiency, solids retention and product losses by elutriation of fine particles on drier walls. The effect of selected independent variables on the drier stability was also evaluated based on a parameter defined as the ratio between the feed suspension volume and the total inert particles volume. Finally, the powder quality was verified in experiments with fixed feed flow and varying air drying temperature, drying air velocity and intermittence time. It was observed that the suspension interferes in the spouted bed drier fluidynamics behavior, and higher air flow is necessary to stabilize the drier. The suspension also promotes the expansion of the spouted bed diameter, decreases the solid circulation and favors the air distribution at the flush area. All variables interfere in the spouted bed performance, and the solids concentration has a major effect on the material retention and losses. The intermittence time also has great effect on the stability and material retention. When it comes to production efficiency, the main effect observed was the drying air temperature. First order models were well adjusted to retention and losses data. The acerola powder presented ascorbic acid levels around 600 to 700 mg/100g. Similar moisture and ascorbic acid levels were obtained for powders obtained by spouted bed and spray drier. However, the powder production efficiency of the spray drier was lower when compared to spouted bed drier. When it comes to energetic analysis, the spray drier process was superior. The results obtained for spouted bed drier are promising and highly dependent on the operational parameters chosen, but in general, it is inferred that this drying process is adequate for paste and suspension drying

Projeto e Operação em Escala Semi-Industrial de um Equipamento para Tratamento de Águas Produzidas na Indústria do Petróleo Utilizando Nova Tecnologia: misturador-decantador à inversão de fases - MDIF

The aim of this work is to use a new technology in the treatment of produced wastewaters from oil industry. An unit for treat produced waters called UTMDIF, was designed, installed and operated in an industrial plant for treatment of effluents from oil industry. This unit operates by means of the method of separation of phase inversion and can become a promising alternative to solve the problem of oil/water separation. This method constitutes the basis of the working of a new design of mixersettler of vertical configuration which occupies small surface area. The last characteristic becomes specially important when there is limitation on the lay-out of the plant, for example, over maritime platforms to explore oil. This equipment in a semi-industrial scale treats produced wastewaters contaminated with oil at low concentrations (ranging from 30 to 150 mg/L) and throughputs of 320 m3/d (47,4 m3 m-2 h-1). Good results were obtained in oil/water separation which leads to the necessary specification to discharge those wastewaters. Besides, the non dependence of the efficiency of separation in spite of the salinity of the medium becomes the equipment an attractive new technology to treat wastewaters containing oil at low concentrations

Estudo de técnicas para o tratamento alternativo de efluentes oleosos oriundos da industrialização da castanha de caju

An evaluation project was conducted on the technique of treatment for effluent oil which is the deriving process to improve cashews. During the evaluation the following techniques were developed: advanced processes of humid oxidation, oxidative processes, processes of biological treatment and processes of adsorption. The assays had been carried through in kinetic models, with an evaluation of the quality of the process by means of determining the chemical demand of oxygen (defined as a technique of control by means of comparative study between the available techniques). The results demonstrated that the natural biodegradation of the effluent ones is limited, as result using the present natural flora in the effluent one revealed impracticable for an application in the industrial systems, independent of the evaluation environment (with or without the oxygen presence). The job of specific microorganisms for the oily composite degradation developed the viability technique of this route, the acceptable levels of inclusion in effluent system of treatment of the improvement of the cashew being highly good with reasonable levels of removal of CDO. However, the use combined with other techniques of daily pay-treatment for these effluent ones revealed to still be more efficient for the context of the treatment of effluent and discarding in receiving bodies in acceptable standards for resolution CONAMA 357/2005. While the significant generation of solid residues the process of adsorption with agroindustrial residues (in special the chitosan) is a technical viable alternative, however, when applied only for the treatment of the effluent ones for discarding in bodies of water, the economic viability is harmed and minimized ambient profits. Though, it was proven that if used for ends of I reuse, the viability is equalized and justifies the investments. There was a study of the photochemistry process which have are applicable to the treatment of the effluent ones, having resulted more satisfactory than those gotten for the UV-Peroxide techniques. There was different result on the one waited for the use of catalyses used in the process of Photo. The catalyses contained the mixing oxide base of Cerium and Manganese, incorporated of Potassium promoters this had presented the best results in the decomposition of the involved pollutants. Having itself an agreed form the gotten photochemistry daily paytreatment resulted, then after disinfection with chlorine the characteristics next the portability to the water were guarantee. The job of the humid oxidation presented significant results in the removal of pollutants; however, its high cost alone is made possible for job in projects of reuses, areas of low scarcity and of raised costs with the capitation/acquisition of the water, in special, for use for industrial and potable use. The route with better economic conditions and techniques for the job in the treatment of the effluent ones of the improvement of the cashew possesses the sequence to follow: conventional process of separation water-oil, photochemistry process and finally, the complementary biological treatment

Determinação de Dados de Equilíbrio Líquido-Vapor para Sistemas Hidrocarbonetos e Desenvolvimento de uma Nova Célula Dinâmica

In the present work are established initially the fundamental relationships of thermodynamics that govern the equilibrium between phases, the models used for the description of the behavior non ideal of the liquid and vapor phases in conditions of low pressures. This work seeks the determination of vapor-liquid equilibrium (VLE) data for a series of multicomponents mixtures of saturated aliphatic hydrocarbons, prepared synthetically starting from substances with analytical degree and the development of a new dynamic cell with circulation of the vapor phase. The apparatus and experimental procedures developed are described and applied for the determination of VLE data. VLE isobarics data were obtained through a Fischer's ebulliometer of circulation of both phases, for the systems pentane + dodecane, heptane + dodecane and decane + dodecane. Using the two new dynamic cells especially projected, of easy operation and low cost, with circulation of the vapor phase, data for the systems heptane + decane + dodecane, acetone + water, tween 20 + dodecane, phenol + water and distillation curves of a gasoline without addictive were measured. Compositions of the equilibrium phases were found by densimetry, chromatography, and total organic carbon analyzer. Calibration curves of density versus composition were prepared from synthetic mixtures and the behavior excess volumes were evaluated. The VLE data obtained experimentally for the hydrocarbon and aqueous systems were submitted to the test of thermodynamic consistency, as well as the obtained from the literature data for another binary systems, mainly in the bank DDB (Dortmund Data Bank), where the Gibbs-Duhem equation is used obtaining a satisfactory data base. The results of the thermodynamic consistency tests for the binary and ternary systems were evaluated in terms of deviations for applications such as model development. Later, those groups of data (tested and approved) were used in the KijPoly program for the determination of the binary kij parameters of the cubic equations of state original Peng-Robinson and with the expanded alpha function. These obtained parameters can be applied for simulation of the reservoirs petroleum conditions and of the several distillation processes found in the petrochemistry industry, through simulators. The two designed dynamic cells used equipments of national technology for the determination Humberto Neves Maia de Oliveira Tese de Doutorado PPGEQ/PRH-ANP 14/UFRN of VLE data were well succeed, demonstrating efficiency and low cost. Multicomponents systems, mixtures of components of different molecular weights and also diluted solutions may be studied in these developed VLE cells

Opiniões de professores do ensino médio: refletindo sobre os projetos escolares e a interdisciplinaridade

Official documents indicate to a curriculum organization that promotes the dialogue in different areas of knowledge. Among the proposals strategies are the "School Projects". This research appears from the staff need evidenced in the development of practice of the researcher in recent years as Pedagogical Advisor in high school. The comments made in the daily work on the kinds of projects and how they were developed in the school, generated concerns. They aroused the interest in further the discussion, aiming to reflect with teachers about the implementation of a pedagogic action on the use of educational projects in the classroom, as a didactic strategy which promotes the learning of students. In this sense, it seeks to develop studies and discussions by the application of questionnaires and the holding of a workshop with teachers in the area of Science of Nature and Mathematics in private high school institutions from Natal, searching opinions of them as the preparation and development of school projects. As general purpose, it aims to contribute with elements to the reflection of the teachers on the use of this strategy of education. For both, we propose: the knowledge of ideas/opinions of teachers on planning, development and evaluation of projects, both disciplinary and interdisciplinary, identifying the main difficulties of these teachers about the work with projects at school; reviewing projects developed at school after the press conference in a meeting with teachers, incorporating the identified aspects as weak points. In the course of the methodology research, questionnaires were used with open and closed questions for the lifting of preliminary ideas for teachers in order to subsidize the planning of a developed meeting later in the school itself on the subject in question. 10 teachers took part of the first step and 17 in the second one (pressconference). In the third stage, an individual interview was carried out and analysis of projects already developed. It is observed that, as the main difficulty for the development of projects in school, pointed to the time factor in the planning team, followed by excessive working hours for teachers that, generally, also work in other schools. Some teachers say they do not develop projects for not having knowledge of how to develop school projects, neither disciplinary, nor interdisciplinary

Projetos de letramento na educação de jovens e adultos: o ensino da escrita em uma perspectiva emancipatória

This ethnographical research-action is included in the Applied Linguistics area and its study object is related to literacy projects (KLEIMAN, 2000), since they bring a new sense to the literacy practices in school and emphasizes the agentive writing character and the role of the discursive genres in the formation of literacy agents who aim at the action and the social change. Considering the emancipatory potential that these didactic organizations have in the civic literacy of those who live in social risk and vulnerability situations our aim in this investigation is: to reflect about the role of the redefinition of the literacy school practices and investigate how the action of teachers and students as literacy agents occur. The specific aims are: to promote literacy events which encourage the writing practice for the action and social change; to comprehend how the identity construction of the literacy student-agent occurs by the reflection of its agency process in the literacy projects; to identify teaching strategies and procedures which enable the development of emancipatory language practices; to investigate the axiological values constructed by the learners in and about the writing work in literacy projects. Our discussion is based on the language conception supported by Bakhtin (BAKHTIN/VOLOSHINOV, 2000; BAKHTIN, 1990, 2003); in literacy studies (KLEIMAN, 1995; BAYNHAM, 1995; BARTON; HAMILTON; IVANIC, 2000, LAZERE, 2005); on critical studies which defend the idea that the texts are ideological instruments able to give power to the individuals (MCLAREN, 1988, 1991, 1997, 1999, 2000, 2001; FREIRE, 1971, 1978, 1979, 1982, 1992, 1996, 2001a, 2001b, 2009; GIROUX, 1983, 1986, 1990, 1992, 1997, 1999, 2003; APPLE, 1989); on the social genre approach inspired by the New Rhetoric (BAZERMAN, 2005, 2006, 2007; MILLER, 1984, 2009). The data were generated between 2006 and 2010 in the Youth and Adult Education (YAE), in public schools in Natal-RN. The research permitted us to deduce, firstly, that the redefinition of the work with discursive genres provide the learner to read and write to act discursively in the social world, earning, thus, empowerment, autonomy and emancipation; secondly, that involving the students in literacy projects goes beyond didactic competence related to specificities and content domain. It is necessary that the teacher is certain about to whom, what, why and how to teach and that he/she gets a reflexive posture, becoming a learner as well; thirdly, that through the literacy practices which were developed, the collaborators of the research have constructed a more conscious and a more critical view in relation to the language and to the world where they live through the social-political writing and they have improved as interventive and politicized citizens

Lazer na terceira idade: desenvolvimento humano e qualidade de vida

The article aimed to understand the concept of leisure and understanding that older people have about their benefits to the quality of life as part of the idleness of the population. We used a sample of subjects living in the city of Bauru, SP, aged less than fifty years, of both sexes and economically disadvantaged class. It was used in literature, documentary and field. We developed an intervention project that aimed to education for leisure. It was the conclusion that public policies are necessary and qualified professionals for construction projects and equipment to expand the Recreation, spreading it and reaching the people of old age since previous stages of life. Materials with simple and low cost, the project of intervention, it reached the recreation-education and education for leisure satisfactorily.

Maturidade em gerenciamento de projetos no contexto da gestão estratégica no setor público: análise na Secretaria de Estado da Tributação do Rio Grande do Norte

This paperwork attempts to measure the project management maturity in the State Department of Taxation in Rio Grande do Norte. Project management has shown to be a critical component to any organization success, as the projects are directly related to a set of activities resulting into organizational innovations such as products, services and processes; and its improvement is directly aligned with the strategic management. Methodologically, this paperwork uses both a quantitative and qualitative approach that will be applied to the coordinators, sub-coordinators, and directors of the Regional Offices of the State Department of Taxation. In the theoretical reference it is about the public management and analyzes the strategic management in contemporary public administration. Presents the maturity in project management is by discussing the main models: CMM, Capability Maturity Model; PMMM, Project Management Maturity Model; OPM3, Organization Project Maturity Model and the Prado-MMGP, Modelo de Maturidade em Gerenciamento de Projetos. From this analysis, considering attributes as an aid in taking strategic positioning, access to the model, possibility of benchmarking and continuous improvement, the Prado-MMGP model was the most appropriate for this research process. It has been proved that the State Department of Taxation shows a very low project management maturity level. Regarding the acceptance of the maturity dimensions by the State Department, it is still in an early developmental stage, as one of the dimensions showed a poor performance while the rest showed a regular one. In contrast with similar organizations, the maturity results have shown to be below the national average. The maturity assessment enables in the institution the implementation of a plan for institutional growth with the creation of sector strategic and project management

Natal, outra cidade : o papel da Intendência Municipal no desenvolvimento de uma nova ordem urbana(1904-1929)

The present work regards, as its subject, the management of the urban space. It aims to survey the role assumed by the Conselho de Intendência Municipal de Natal (Municipal Stewardship Council of Natal) in the formation of a new urban order between the years of 1904 and 1929. For a better comprehension of the object of research, the milestone of the time span analyzed in this work was receded to the year of 1890, specifically at the first chapter of this dissertation. In this chapter, we will turn our attention towards an analysis of the referred council, on the regulation of its operation, the relations of this institution with the state government and its mechanisms of action in the city, among other topics. In the next chapter, we will delve into an elite who administrated the city of Natal during the first republic, understanding that the analysis of the formation of a modern city project by the Municipal Stewardship undergoes the comprehension of those who leaded this institution. In the third chapter, we will examine the limits of the municipal management to put into practice its projects to the upraise of a new Natal, between the years of 1904 and 1921. The last chapter, on its turn, presents a new Stewardship, reformulated after a process of administrative streamlining, and a city that transforms itself, especially during the O Grady tenure by receiving major constructions, which alter its main features. We will regard, as the main resources of this study, articles from the daily newspapers A República (The Republic) and Diário de Natal (Daily Natal), dictums, announcements, laws, state decrees and the messages disclosed by the state government. To build a way of analysis, we make use of authors such as Anthony Giddens, Peter Burke and Laurent Vidal, among many others who discuss concepts related to the proposed theme

A Psicologia do trabalho e das organizações na formação do psicólogo no Brasil

This research has aimed to analyze the presence of the Work and Organizational Psychology (WOP) at the psychologist s undergraduate education after 2004 s National Curricular Guidelines in Brazil. It has investigated in 43 Brazilian undergraduate courses of Psychology how their Course Pedagogical Projects (CPPs) approach the WOP issues. For that investigation, the CPPs, the subjects programmes related to the WOP and the curriculum grid have been accurately read and analyzed. Categories created by similar studies have also been used. The studied knowledge field has been cited by 41 courses, mainly on the definition of the egress s professional profile, on the expected competences and on the psychologist s formation process lines. Moreover, 28 courses have disposed curricular emphasis on the WOP and 12 have provided professional practices on that Psychology s field. All the courses have displayed, at least, one subject related to the WOP and in 29 cases there have been found between two and six subjects concerned to that field of Psychology, occupying nearby 10% of the whole courses credit hours. It has been verified that the Work and Organizational Psychology is allied to discussions about Quality of Life and Health of the Worker, bonded to work prescriptions at the Personnel Management departments and in other places such as syndicates. Additionally, 37% (147) of the WOP s subjects concerns to the contents of the Work Psychology, 21% (81) relates to the Organizational Psychology, 18% (71) are about Industrial Psychology s topics and 14% (55) debates the field generically. The most often issues are: Recruitment and Selection (25 courses); Training, Development, Learning and Education (24); and Work and Mental Health (24). Those topics have assumed three functions: providing principles for the acting at the WOP field; tutoring psychologists to analyze their own workplaces; and offering a comprehension of the human being mediated by the Work. It has been concluded that the WOP is incorporated on the psychologist s undergraduate education by considering the increasing of its presence and the occurrence of its traditional and emergent topics