1000 resultados para Matriz extracelular Teses


Relevância:

20.00% 20.00%

Publicador:

Resumo:

This research was motivated by the requirement of asbestos s replacement in building systems and the need to generate jobs and income in the country side of the state of Bahia, Brazil. The project aimed at using fibers from licuri leaves (syagrus coronata), an abundant palm in the region, to produce composites appropriate for the sustainable production of cement fibre reinforced products in small plants. The composites were produced in laboratory using Portland cement CP-II-F32, sand, water, licuri palm fiber contents of 1.0, 1.5 and 2.0% by weight of binder (two different fiber length) and metakaolin. The latter was chosen as an additional binder for its efficiency to reduce the alkalinity of cementitious matrixes therefore preventing the degradation of vegetable fibers. The characterization of the composite components was carried out by sieving and laser particle size analyses, thermal analysis, fluorescence and X-ray diffraction. The composites performance was evaluated by 3- point-bending tests, compressive strength, ultrasound module of elasticity, free and restrained shrinkage, water capillarity absorption and apparent specific gravity. It has been found that the addition of fibers increased the time to onset of cracking over 200.00% and a 25% reduction in cracks opening in the restrained shrinkage test. The capillary absorption reduced about 25% when compared to fiber-free composites. It was also observed with regard to flexural strength, compressive strength and specific gravity, that the addiction of fibers did not affect the composite performance presenting similar results for compounds with and without fibers. In general it can be stated that the reinforced composite fibers of palm licuri presents physical and mechanical characteristics which enable them to be used in the intended proposals of this research

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis is a translation of work of the Brazilian doctor, Pedro da Silva Nava (1903-1984), in particular, his memoirs and chronicles, articulated with the writings of medicine history, aiming to defend that the autobiographical narratives are sources of research capable of promoting discussions on the expansion of the present at the confluence of complex and unequal society in constant changing process as the Brazilian. The theoretical and methodological support circulates around studies, proposals and thesis by Boaventura Santos about empowering past, destabilizing subjectivity, sociology of absences, cosmopolitan reason and translation work. The empirical support drawn from the literature produced by Nava were analyzed with reference this reasoning and studies that have facilitated the flow of translation among others, the studies of Antonio Candido, Arrigucci Jr., Boris Cyrulnik, Beatriz Sarlo, Ecla Bosi, talo Calvino, Jos Willington Germano, Jos Maria Canado, Lev Vygotsky, Marilena Chau, Paul Riceur and Walter Benjamim, without neglecting what we consider indispensable to scientific research, the production of relevant knowledge and prudent, in view of a decent life. The initial inflections reflect the subject of the Memoirs and its education/training, to then place the Memoir subject in the literary context, scientific, historical and Brazilian poetic (1972-2010), bringing great interpreters and discussing the rationale used by the Narrator that we defend stand closer to the cosmopolitan, showing the formation of narratives whose presence insert itself beforehand to modernist verve, linked to the discursive array against the literature as domination space, disseminated in Brazil in the early twentieth century. So, it articulate with those in which the concerns adjust the construction of the social formation of Brazil as a national heritage through literary narrative that focuses on a historical principle that becomes the past empowering, allowing his rereading, whose converge to memory, the lifestyles, the plurality of language and Brazilian culture, formed by several people, converging into a design not of culture but multiculturalism in Brazil. The memory issue was addressed in the space-time of experiences of being that narrates, shaped by a destabilizing subjectivity that sought to order the testimony of a time, a history and society, retelling them by creative imagination, almost fictional, to make circulate his knowledge about Brazil attached to his medical knowledge, as well as other subjects in his living group and other groups with whom they maintained contact. Thus, he portrayed both tangible and intangible cultural assets of the country as a form of preservation, giving them meanings and sense. It approaches, therefore, from the perspective of sociology of absences, the expansion of the present and by the logic inherent in his narratives of self and Brazil

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The way of organization of the constitutional jurisdiction implies the possibility to extend the democratization of the same one in function of the popular participation in the active legitimacy to constitutional process (procedimentalist model) e, at the same time, to assure technical viable decisions fast and to the complex problems of the constitucional law (substancialist model). The comparison with the constitutional jurisdiction of U.S.A. becomes interesting from the knowledge of the wide power to decide experience of Supreme the Court that for a methodology of construction of rights and not simply of interpretation of the Constitution, brought up to date and reconstructed throughout its historical evolution the direction of the norms of basic rights and the North American principles constitutional. Construction while constitutional hermeneutic method of substancialist matrix works with techniques as the measurement of principles, the protection of interests of minorities and the entailing of the basic rights with values politicians, what it can be brought to evidence of the Brazilian constitutional jurisdiction in order to improve the construction of basic rights that comes being carried through for the judicial ativism in control of the diffuse and abstract constitutionality. To define the limits of construction is to search, on the other hand, a dialogue with the procedimentalists thesis, aiming at the widening of the participation of the citizen in the construction of the basic rights for the constitutional process and to argue forms of the society to evaluate the pronounced decisions activist in the controls diffuse and abstract of constitutionality

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The contemporary conjuncture based on the capitalistic knowledge converges to the corporal consciousness that makes us see, feel, taste and hear, be in/to pieces. Disembodied reason legitimate and legislate ways of being and living socially and its development is the dehumanization of human relations causing pain and suffering. The objective of this work is to discuss the body as pedagogical matrix through imagistic/artistic elements: music, painting and literature. Metaphors lead to self knowledge of human subjectivity and approach us to the kaleidoscope of sensitive knowledge and enables learning to learn with the infinite combinations of images, knowledge, feelings and worldviews. The song Memria da Pele comes in the voice of Maria Betnia speak of the memories that are not mine, but are tattooed in me in the memory of skin, singing the memories of a love lived by who tries to forget rationally, but the body insists on remembering. It is password to think about what we are. The short story by Clarice Lispector, entitled Miss Algarve, narrates the life story of an unmarried and virgin woman, and her encounter with an alien called Ixtlan. Until then, she who lived as if every day were a Monday, found herself seduced by the pleasure of having a body in contact with another body, which also allowed her to give visibility to the bodies of others. She had repudiation by the immorality that her body and the other s perspired. The discovery of the body brings important lessons for nursing, involving our body and the others'. The painting the flying bed or Henry Ford Hospital, by Frida Kahlo, is our final metaphor. The traumatic experience of abortion is shown in this painting trough the picture of the artist naked in a hospital bed. This painting invites us to reflect on our work process. We need to think in multiple dimensions of the being and accept the invitation of art, so that the lightness confronts us with the weight imposed by the hegemonic ideology. I believe it is not a single view, but the many views that should justify the knowledge and practices of nursing; what matters is that they are woven into the dialogue, democracy, provided that protagonism of those individuals involved in this process, in the wandering and uncertainty, in the rewiring, solidarity, plurality. To this end, the body must be the great pedagogue that is able to be viewed not as a tapestry seen by the right view, as the logical knowledge sees, but seen by the opposite side in its singular, irregular, discontinuous weavings

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Em Gois, o pequi (Caryocar brasiliense) se destaca, dentre as frutferas nativas do Cerrado, como promissora para a produo comercial. Um dos obstculos para a sua produo em grande escala, no entanto, o fato de que a germinao de sementes seja baixa e irregular. Com o objetivo de avaliar a emergncia de sementes de pequizeiro e o desenvolvimento inicial de mudas oriundas de 16 plantas, aos dez meses aps a colheita, na presena e ausncia de cido giberlico (GA3), foram conduzidos dois experimentos. O primeiro foi implantado em delineamento de blocos ao acaso, com parcelas subdivididas, tendo as matrizes nas parcelas e, nas subparcelas, um tratamento de imerso por 48 horas, em gua pura e em soluo de 500 mg L-1 de GA3. Foram realizadas avaliaes a cada sete dias, para determinao da percentagem final, tempo mdio e ndice de velocidade de emergncia. Para o segundo experimento, foi utilizado delineamento inteiramente casualizado, com nmero variado de repeties, de acordo com o nmero de mudas obtidas no primeiro experimento. Para percentagem, ndice de velocidade e tempo mdio de emergncia, o efeito dos tratamentos foi significativo, sendo que, para os dois primeiros, houve interao significativa entre gentipo e tratamento, para superao da dormncia. Observou-se que a utilizao de 500 mg L-1 de cido giberlico pode minimizar a dormncia em sementes de Caryocar brasiliense e que o crescimento das matrizes em campo foi linear e contnuo, ao longo do tempo.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis intends to show the level of pollutant emissions in the State of Rio Grande do Norte, generated by the final consumption of energy in the many different sectors of the economy. This information was obtained from the energetic matrix and from the pollutant emissions of the State and the data was taken from the Balano Energtico Estadual and from the Sistema de Informaes Energticas da Olade. The result will permit to identify the energy and most polluting economic sectors in Rio Grande do Norte, contributing to energy planning, giving direction to the public policy development that aim at the change of the energy matrix of the State. Also with the objective of reducing pollutant emissions through rationalization, efficiency and energy substitution, which the main objective is to promote the economic development based on energy consumption of less harmful impact on the environment, contributing to establishment of sustainable development

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Avaliaram-se os efeitos da incluso de fitase e de sua matriz nutricional em raes contendo sorgo sobre o desempenho das aves, a qualidade dos ovos, a ingesto e a excreo e reteno de fsforo e nitrognio em poedeiras comerciais. Utilizaram-se 180 poedeiras comerciais, distribudas em delineamento inteiramente ao acaso em esquema fatorial 2 2 + 1, com dois nveis de fitase (0 e 500 FTU/kg de rao) e dois nveis de substituio do milho pelo sorgo (50 e 100%) e uma rao testemunha (isenta de sorgo e fitase), constituindo cinco tratamentos com seis repeties de seis aves. As raes foram base de milho e farelo de soja, sem fitase e sorgo, considerando a matriz nutricional da fitase. O desempenho e a qualidade dos ovos foram avaliados em quatro perodos de 28 dias. Ao final do experimento, um ensaio de metabolismo foi realizado para quantificar a ingesto, excreo e reteno aparente de fsforo e nitrognio e avaliar a viabilidade econmica das raes. Ao considerar a matriz nutricional da fitase, as exigncias em energia, clcio, fsforo, protena e aminocidos foram atendidas, mesmo com a reduo dos nveis nutricionais da dieta, e o desempenho e a qualidade dos ovos no foram comprometidos. A adio de fitase nas raes possibilitou reduzir todos os parmetros econmicos avaliados. O sorgo pode substituir totalmente o milho e ser o nico gro energtico da dieta.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Cento e oitenta poedeiras comerciais Isa Brown, com 60 semanas de idade, foram distribudas em delineamento inteiramente ao acaso, em esquema fatorial 2 2, com dois nveis de fitase (0 e 500 ftu/kg de rao) e dois de farelo de girassol (4 e 8%), totalizando cinco dietas, avaliadas com seis repeties de seis aves. As dietas foram formuladas a partir de uma rao controle, base de milho e farelo de soja, isenta de fitase e farelo de girassol, valorizando na formulao das dietas a matriz nutricional da fitase. O perodo experimental foi dividido em quatro ciclos de 28 dias cada. A matriz nutricional preconizada para fitase permitiu o atendimento pleno das exigncias das aves, mesmo quando as dietas foram formuladas com nveis nutricionais reduzidos, isso quando desconsiderados os nutrientes presentes na matriz nutricional da enzima, de acordo com recomendao da empresa produtora. A adio de fitase na dieta reduz a excreo de fsforo pelas aves e melhora os parmetros econmicos. A incluso de farelo de girassol no nvel de 8% prejudica a produo de ovos, mas no afeta os demais parmetros de desempenho e qualidade dos ovos.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In this study were conducted experimental procedures for determination of variation of the expandability of rigid polyurethane foam (PUR) from a natural oil polyol (NOP), specifically the Castor oil plant, Ricinus communis, pure and additions of the vermiculite in phase dispersed in different percentage within a range from 0% to 20%, mass replacement. From the information acquired, were defined the parameters for production of bodies of test, plates obtained through controlled expansion, with the final volume fixed. Initially, the plates were subjected to thermal performance tests and evaluated the temperature profiles, to later be extracted samples duly prepared in accordance with the conditions required for each test. Was proceeded then the measurement of the coefficient of thermal conductivity, volumetric capacity heat and thermal diffusivity. The findings values were compared with the results obtained in the tests of thermal performance, contributing to validation of the same. Ultimately, it was investigated the influence that changes in physical-chemical structure of the material had exerted on the variation of thermophysical quantities through gas pycnometry, scanning electron microscopy (SEM) combined with energy dispersive X-ray fluorescence spectroscopy (EDXRF), infrared spectroscopy using Fourier transform (FTIR), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). Based on the results obtained was possible to demonstrate that all load percentage analyzed promoted an increase in the potential expansion (PE) of the resin. In production of the plates, the composites with density near at the free expansion presented high contraction during the cure, being the of higher density adopted as definitive standard. In the thermal performance tests, the heating and cooling curves of the different composites had presented symmetry and values very close for lines of the temperature. The results obtained for the thermophysical properties of composites, showed little difference in respect of pure foam. The percentage of open pores and irregularities in the morphology of the composites were proportionate to the increment of vermiculite. In the interaction between the matrix and dispersed phase, there were no chemical transformations in the region of interface and new compounds were not generated. The composites of PUR-NOP and vermiculite presented thermal insulating properties near the foam pure and percentage significantly less plastic in its composition, to the formulation with 10% of load

Relevância:

20.00% 20.00%

Publicador:

Resumo:

In the execution of civil engineering works, either by wasting during the coating of wall or demolition of gypsum walls, the generation of the gypsum waste involves serious environmental concerns. These concerns are increased by the high demand of this raw material in the sector and by the difficulties of proper disposal byproduct generated. In the search for alternatives to minimize this problem, many research works are being conducted, giving emphasis in using gypsum waste as fillers in composites materials in order to improve the acoustic, thermal and mechanical performances. Through empirical testing, it was observed that the crystallization water contained in the residue (CaSO4.2H2O) could act like primary agent in the expanding of the polyurethane foam. Considering that polyurethane produced from vegetable oils are biodegradable synthetic polymers and that are admittedly to represent an alternative to petrochemical synthetic polyurethane, this research consist an analysis of the thermal behavior of a composite whose matrix obtained from a resin derived from the expansive castor oil seed, with loads of 4%, 8%, 12% and 16% of gypsum waste replacing to the polyol prepolymer blend. Contributors to this analysis: a characterization of the raw material through analysis of spectroscopy by Fourier transform infrared (FTIR), chemical analysis by X-Ray Fluorescence (XRF) and mineralogical analysis by X Ray Diffraction (XRD), complemented by thermo gravimetric analysis (TGA). In order to evaluate the thermo physical properties and thermal behavior of the composites manufactured in die closed with expansion contained, were also carried tests to determine the percentage of open pore volume using a gas pycnometer, scanning electronic microscopy (SEM), in addition to testing of flammability and the resistance to contact with hot surfaces. Through the analysis of the results, it appears that it is possible to produce a new material, which few changes in their thermo physical properties and thermal performance, promotes significant changes and attractive to the environment

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Use of natural fibres as a reinforcement material in the manufacture of composites show a series of advantages: availability, biodegradability, low weight and regeneration in relation to synthetic fibres, thus justifying its utilization. In the present research work, composites were developed with chicken feathers (KF), using unsaturated polyester resin as matrix, for diversified applications, mainly in the furniture/timber industry.At present, in Brazil the chicken feathers are used as part of the animal feed, even though this material possesses low aggregated value. The chicken feathers are hollow, light and resistant. After washing with water at room temperature, a part of the chicken feathers were treated with 2% NaOH. Composites were manufactured using treated and untreated chicken feathers with unsaturated orthothalic polyester resin and 1% peroxide as catalyser, obtained in the commerce. Samples with size 150x25x3 mm for mechanical tests were cut by laser in the composite plate. Mechanical analyses were carried out in the Laboratrio de Metais e Ensaios Mecnicos UFRN. All the analyses were in accordance with ASTM standards. SEM analyses were also carried out on the samples.In the analyses of the results obtained, it was observed that the composites made with untreated chicken feathers showed better results (Traction 11.406 MPa and 9.107 MPa Bending 34.947 and 20.918 MPa for samples with and without treatment respectively) compared to the composite with treated feathers. Very low values of the water absorption results, evidenced the impermeability characteristic of the feathers. From the SEM images, the structure, fracture and the fibre/matrix adsorption can be evidenced. In the flammability test, it was observed that despite the feathers having sulfur as a constituent, natural inhibitor of flame, no burning support of the composites, because the manufacturing process of the composite

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Space Science was built using a composite made of plaster, EPS, shredded tires, cement and water. Studies were conducted to thermal and mechanical resistance. Inside the mold EPS plates were placed in order to obtain a higher thermal resistance on the wall constructed, as well as to give it an end environmentally friendly in view of both the tire and the EPS occupy a large space in landfills and year need to be degraded when released into the environment. Compression tests were performed according to ABNT blocks to seal, measurements of the temperature variation in the external and internal walls using a laser thermometer and check the temperature of the indoor environment using a thermocouple attached to a digital thermometer. The experiments demonstrated the heat provided by the composite values from the temperature difference between the internal and external surfaces on the walls, reaching levels of 12.4 C and room temperature in the interior space of the Science of 33.3 C, remaining within the zone thermal comfort for hot climate countries. It was also demonstrated the proper mechanical strength of such a composite for sealing walls. The proposed use of the composite can contribute to reducing the extreme housing shortage in our country, producing popular homes at low cost and with little time to work

Relevância:

20.00% 20.00%

Publicador:

Resumo:

With a view to revitalizing public environments through criteria that include economy, tourism, aesthetics and respect for the environment, this paper proposes a model of kiosk manufactured with composite material blocks, to be employed as a public instrument. . The model consists of a structure composed of planned blocks and manufactured in cement-based composite, gypsum, ground and water, having the styrofoam inside filled with pet bottles of 500 ml dose. The social and environmental issue is the critical point of the work when it can, through the reuse of environmentally harmful materials such as polyethylene terephthalate PET, using such modules for the construction of various areas of Commerce, promoting the protection of the environment combined with the improvement of the quality of life of the population. The tourism factor, which is significant in the economy of the North, is also considered as the modulated kiosk has a visual aspect innovative and differentiated. The environmental issue is addressed by encouraging the reuse of PET material and EPS (polystyrene)

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Composite materials can be defined as materials formed from two or more constituents with different compositions, structures and properties, which are separated by an interface. The main objective in producing composites is to combine different materials to produce a single device with superior properties to the component unit. The present study used a composite consisting of plaster, cement, EPS, tire, PET and water to build prototype solar attempt to reduce the manufacturing cost of such equipment. It was built two box type solar cookers, a cooler to be cooled by solar energy, a solar dryer and a solar cooker concentration. For these prototypes were discussed the processes of construction and assembly, determination of thermal and mechanical properties, and raising the performance of such solar systems. Were also determined the proportions of the constituents of the composite materials according to specific performance of each prototype designed. This compound proved to be feasible for the manufacture of such equipment, low cost and easy manufacturing and assembly processes

Relevância:

20.00% 20.00%

Publicador:

Resumo:

One of the waste generated during the drilling of oil wells are gravel which are impregnated of drilling fluid. This residue consists of highly toxic chemicals, including toxic metals. This study suggests an alternative process to the treatment of this waste, by incorporating it the form of raw material in the ceramic matrix , and by solidification and stabilize the metals present, Aluminum (Al), Iron (Fe), Manganese (Mn) and Zinc (Zn). The raw materials were characterized by the techniques of X ray fluorescence (FRX), X ray diffraction (DRX), laser granulometry (GL), thermogravimetry (TG) and differential thermal analysis (ADT). To evaluate the percentage of gravel effect the environmental and technological properties were obtained from formulations containing 0, 10 and 20 % by weight of gravel in the ceramic matrix. After sintering at temperatures 1080, 1120 and 1160 C, the samples were tested for water absorption, the linear shrinkage firing, voltage of rupture and solubility. The results obtained showed that the stabilization by solidification, is a viable alternative to safe disposal of waste drilling. Ceramics products can be used in the manufacture of solid bricks