Submitted by CARMEN HANNUD CARBALLEDA ADSUARA null (adsuara.psicologia@gmail.com) on 2016-09-01T12:47:29Z No. of bitstreams: 1 Dissertação Carmen. Defesa.pdf: 1776255 bytes, checksum: 62e793485de77458dd34a8d099cf0da7 (MD5) / Rejected by Ana Paula Grisoto (grisotoana@reitoria.unesp.br), reason: Solicitamos que realize uma nova submissão seguindo a orientação abaixo: O arquivo submetido está sem a ficha catalográfica. A versão submetida por você é considerada a versão final da dissertação/tese, portanto não poderá ocorrer qualquer alteração em seu conteúdo após a aprovação. Corrija esta informação e realize uma nova submissão contendo o arquivo correto. Agradecemos a compreensão. on 2016-09-01T12:52:17Z (GMT) / Submitted by CARMEN HANNUD CARBALLEDA ADSUARA null (adsuara.psicologia@gmail.com) on 2016-09-01T13:03:06Z No. of bitstreams: 1 Dissertação Carmen. Defesa.pdf: 1849489 bytes, checksum: 1fd00455460ad33e2e54318047b92f50 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-02T13:48:46Z (GMT) No. of bitstreams: 1 adsuara_ch_me_arafcl.pdf: 1849489 bytes, checksum: 1fd00455460ad33e2e54318047b92f50 (MD5) / Made available in DSpace on 2016-09-02T13:48:46Z (GMT). No. of bitstreams: 1 adsuara_ch_me_arafcl.pdf: 1849489 bytes, checksum: 1fd00455460ad33e2e54318047b92f50 (MD5) Previous issue date: 2016-07-01 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Os Terena de Araribá, Terra Indígena no Estado de São Paulo, reconhecem o Mato Grosso do Sul como seu território de origem, de onde saíram em 1930, por meio de uma ação do Serviço de Proteção aos Índios. A partir dessa mudança, seu ideal de vida plena vem sendo reinventado na perspectiva unatí yapey, inspirada e motivada por referências cotidianas das aldeias onde até hoje vivem seus parentes. Nesse contexto, este trabalho estudou a concepção de bem viver Terena em Araribá, em sua intersecção com uma construção de corpo e de pessoa. Partindo das relações cotidianas, o método etnográfico possibilitou identificar alguns estados considerados indesejáveis e encaminhados a especialistas pelos próprios Terena. Assim, foi possível esmiuçar um pouco da cosmovisão Terena e suas matizes no âmbito do bem viver, das relações de cuidado e cura. / The Terena Araribá, an indigenous land in the State of São Paulo, recognize Mato Grosso do Sul as their original territory, which was left in 1930 because of an action of Indian Protection Service. Since this change, their ideal of full life has been reinvented through the so-called unatí yapey perspective, which is inspired and motivated by everyday references of villages where their relatives currently live. In this context, this paper studied the design of living well in Terena Araribá and its intersection with building of body and individual. Starting from everyday relationships, a range of ethnographic tools made it possible to identify some states considered undesirable and as requiring specialists by Terena people themselves. It was possible to scrutinize some of the Terena worldview and its nuances concerning good life and care and healing relations. / CNPq: 133276/2015-5

The objective of this study is to develop a fast curing phenolic formaldehyde (PF) and polymeric diphenyl methane isocyanate (MDI) based hybrid resin system for wood products applications. Various formulas of PF resins were synthesized with different formaldehyde to phenol ratio, sodium hydroxide to phenol and isocyanate group (-NCO) to hydroxyl group (-OH) molar ratios. The shear bonding strength property was used to evaluate and optimize the formulations by appropriate sample preparation. The optimized resins were characterized by rheometer, Fourier transform infrared spectroscopy (FTIR) and other methods. In order to eliminate the influence of hydroxyl groups from water in the PF resin, a frozen dried method was applied to remove the water while keeping PF resin in liquid state. Acetone was used to disperse the hybrid co-polymer to improve the mobility of the mixture of frozen dried PF resins and MDI. An unexpected phenomenon was observed when the two resins were mixed in acetone and a sharp reaction occurred. This led to an assumption that acetone promoted the curing of hybrid resin. The effect of acetone on the curing behavior of hybrid resin was studied by differential scanning calorimetry (DSC), confocal laser scanning microscope (CLSM) and other techniques. It was confirmed that acetone promoted the curing of the co-polymer system. The gel time of hybrid resin with acetone decreases sharply compared to that of pure phenolic resin and original hybrid resin. Acetone also helped the hybrid resin to have better penetration behavior by improving the mobility and this also resulted in less variation of the strength distribution. Finally, lap shear samples were prepared at room temperature curing commercial polyurethane (PU), phenol-resorcinolormaldehyde resin (PRF) and laboratory made hybrid resins based on PF and MDI to compare the shear strength of different resins under different application conditions. The strength reduction of frozen dried PF with acetone/MDI is the lowest in humidity, temperature and humidity-temperature conditions. With just humidity condition, its shear strength reduction is significantly lower than that of any other resins including the solid wood control.

M.S.

The intent of this research was to enhance our knowledge of aqueous phenolformaldehyde resin cure as it is affected by the elevated water vapor pressures that occur during hot-pressing of a wood-based composite. Microdielectric spectroscopy (DEA) was used to monitor the cure reaction, and thermomechanical analysis (TMA), swelling tests and scanning electron microscopy (SEM) techniques were used to characterize the final resin-network. Microdielectric results showed that as the water vapor pressure of the sy stem increases the time to gelation increases. It was also found that the injection of saturated water vapor sharply decreased the gelation time when compared to the other water vapor environmental conditions. In addition, it was found that the higher the water vapor pressure the lower the residual ion viscosity. Thermomechanical analysis and swelling test experiments showed that as the water vapor pressure increases the glass transition temperature and the cross-link density of the cured resin-network decreases. Considerable differences in the morphology of the network were found using SEM. Thus, it can be established that during the curing process under elevated water vapor pressures of a liquid phenol-formaldehyde adhesive some water is trapped into the resin network and it is acting as a plasticizer. A theoretical approach to model the cure kinetics of phenol-formaldehyde has been developed. The model is based on the occurrence of two simultaneous processes (condensation polymerization and evaporation of water) and on the concentration dependency of the activation energy of polymerization. / Ph. D.

This investigation covered a general study of the effects of the partial loads on the twenty-eight day strength of concrete. Special emphasis was placed on those loads and times of loading that produced the greatest strengths. The work was done using one mix. However, the results for this mix will probably be characteristic of other mixes. all the work,including the making and testing of cylinders, tests for aggregates, slump tests, etc., was done according to the A. S. T. M. standards. It is quite natural that,while investigating one problem, many other interesting problems are thought of in relation to the work, There are some problems related to partial loads that might warrant future study and research, some of these being as follows: 1. A study of the effects of partial loads during the early curing period on concrete beams. 2. A study of the effects of partial loads during the early curing period on various mixes of concrete. 3. A study of conditions actually existing in structures. 4. A study of sections of concrete cylinders cut in various planes which would include concrete that had been partially loaded and concrete that had not been partially loaded. This might lead to a discovery of why the effects of partial loading are produced. / Master of Science

The resin transfer molding (RTM) process has been identified as a cost-effective fabrication technique for producing composite materials from geometrically complex reinforcements. Processing models can be used to determine the temperature and pressure cycles which will produce a finished part with the best properties in the shortest time. This work involved the development and verification of a processing model for RTM. The processing model is based on the assumption that infiltration can be described as flow through a porous medium. Flow through porous media, as governed by D’Arcy’s law, depends on the viscosity of the fluid and the microstructure of the interconnected pores. Infiltration by thermosetting resin systems is assumed to behave as a Newtonian fluid with a time and temperature dependent viscosity. The kinetics of the resin can be described by mathematical expressions determined from standard thermal analysis techniques. The reinforcement is assumed to be a homogenous, anisotropic material which exhibits strain stiffening, hysteresis and plastic deformation. D’Arcy’s law describes the porous material in terms of the material permeability. Kozeny-Carman’s relationship is used to relate the porosity to the permeability. Solution of D’Arcy’s law is accomplished in a quasi-steady state manner by an evolving mesh finite element technique. After infiltration is completed, the model continues to predict the temperature, degree of cure and viscosity of the resin. The equations governing the unsteady heat transfer are solved with an existing cure model by the finite difference method. Results of the processing model include estimates of infiltration, gel and cure times as well as the cured thickness and fiber volume fraction. Test laminates were fabricated, mechanically tested, and compared to prepregged laminate results. Construction of one of the test laminates was simulated with the processing model to verify the accuracy of the simulation. / Master of Science

The purpose of this research was to obtain information on the requirements for successfully drying mechanically harvested Virginia peanuts by artificial means. The work was performed at the Tidewater Research Station, Holland, Virginia. It was performed in bulk-type bins which were seven feet deep. Two tests, which consisted of four treatments and four replications each, were conducted. One of the replication bins in each treatment was divided into one-foot depth sections. The drying tests were conducted using intermittent heat which was designed to give the prescribed temperature rise when the ambient relative humidity was above 75 percent. The drying potential ranged from 12 cfm/ft³ and a 10 F temperature rise to 9 cfm/ft³ and a 3 F temperature rise. Original moisture contents of the peanuts tested were 43 percent and 31 percent. Weights of the bins were taken during the tests, thereby permitting the calculation of the moisture contents at any time. Drying rate curves were obtained from this. Quality analyses of the peanuts after drying were performed in order to determine the best drying treatment. These included: Fat Acidity, Shelling Damage, and Damaged Kernels from Commercial Grade. The Shelling Damage Tests showed that the lowest drying potential was best. The Fat Acidity Test indicated that the drying potential in all of the treatments was satisfactory when drying Virginia peanuts with an original moisture of 31 percent in a seven-foot depth. However, it appeared that the potential was not adequate to dry peanuts with a 43 percent moisture content in a depth greater than five feet. No information was obtained from the damaged kernels in the commercial grade. The resistance to air flow and the analyses of quality of the end product gave no indication that the sectioning of the bins had any effect on drying as compared with the full depth bins. This can be important in later research from the standpoint of obtaining additional data on drying rates and progression of the drying layer through bulk type bins of Virginia peanuts. / Master of Science

Viscoelastic polymer materials are being actively considered as a novel material for semiconductor packaging applications as a result of their ability to develop strong adhesive bonds at lower temperatures. Viscoelastic thermoset materials are impacted by the stresses generated during the curing process, which is also accompanied by a dissipation of thermal energy. There is a need to develop a generic modeling formulation that is applicable to any material of interest in order to enable the study of different bonding materials and develop optimized curing cycles. This study reports a numerical formulation to evaluate the stress generated and energy dissipated during the cure of viscoelastic polymers. A generalized method to define the transient variation of degree of cure was developed using a 4th order Runge Kutta approximation. The mathematical formulation was implemented using a novel evaluation methodology that helped reduce the computational power requirement. The commercially-available 3501-6 resin was simulated as a characteristic material in this study. The numerical model was validated against analytically derived solutions for both a single Maxwell model, and a Generalized Maxwell Model (GMM) for cases of constant-strain inputs, and subsequently for sinusoidal strain inputs, wherein, material properties were considered to be constant or varying linearly with degree of cure. A good agreement was obtained between the present model and analytical solutions.

Charge transfer (CT) complexes have been used in a number of radiation polymerisation processes including grafting and curing. The complexes studied include donor (D) monomers like vinyl ethers and vinyl acetate (VA) with acceptor (A) monomers such as maleic anhydride (MA). Both UV and EB have been utilised as radiation sources. The complexes are directly grafted to these substrates in the presence of radiation. The complexes yield novel copolymers when radiation cured with concurrent grafting improving the properties of the finished product. The term cure grafting has been proposed for this concurrent grafting process. Studies in basic photografting work to complement the cure grafting have been proposed. The role of solvent in grafting is discussed, particularly the effect of aromatics in photografting to naturally occurring trunk polymers like wool and cellulose. The effect of the double bond molar ratio (DBMR) of the DA components in grafting is examined. The ultraviolet (UV) conditions for gel formation during photografting, hence the importance of homopolymer yields in these processes is reported. A plausible mechanism to explain the results from this photografting work is proposed. The significance of these photografting studies in the related field of curing, especially in UV and ionising radiation (EB) systems, is discussed. EB curing and cure grafting of charge transfer (CT) monomer complexes is investigated. The EB results are compared with UV curing and cure grafting of the same complexes. The work has been extended to include EB/UV curing and cure grafting of thiolene systems. The significance of these results in the potential commercial application of these complexes is discussed. Variables affecting the UV/EB curing and cure grafting of thiolenes on cellulose have been studied. These include effect of varying the type of olefin, increasing the functionality of the thiol, use of acrylate monomers and oligomers in hybrid systems, altering the surface structure of the cellulose and finally the role of air in these processes particularly with EB. Photopolymerisation of the thiol-enes in bulk has also been investigated. The thesis content is based on the published work of 14 research papers over the course of the project. / Doctor of Philosophy (PhD)

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