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Reciclagem e caracterização de fibra de carbono presente em compósito de resina epóxi
(Universidade Federal de São Carlos, 2013-04-18) Rodrigues, Gleice Guevara Matielli; Botaro, Vagner Roberto; https://lattes.cnpq.br/2907189124654066; https://lattes.cnpq.br/9748384198258105; Paiva, Jane Maria Faulstich de; http://lattes.cnpq.br/7926832511513537; Silva, Nelson Marques da; http://lattes.cnpq.br/0002397929226146
Carbon fiber reinforced epoxy composites are engineering materials whose are used in a wide range of applications in industries such as automotive, aerospace and sporting goods due to the properties of these composites as strength, durability, low weight and low cost. There are in the literature studies of various methods of recycling carbon fiber at the end of life from parts made with this material. This work reports a study of the polyacrylonitrile carbon fiber reinforced polymer recycling from diglicicil epoxy ether of bisphenol A composite. Initial studies were aimed at finding the best condition to remove the polymer matrix and thereby recover the carbon fiber by heat treatment in a muffle furnace. The matrix was removed at 450°C without degradation of the carbon fiber at 2 hours. The removal of the meanly volatile substances was verified with the Gas Chromatography analysis. The carbon fiber was incorporated randomly in the polyurethane matrix without chemical pre-treatment. The confirmation of the removal of the resin carbon fiber was obtained through the Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR). The characterization of the carbon fiber reinforced polyurethane composite was performed using the techniques: Thermogravimetric Analysis (TGA), Dynamic Mechanical Analysis (DMA) and FTIR. Thus, it was observed that the carbon fiber reinforced polyurethane at 2 % and 3% showed improvement in the mechanical properties since the storage modulus value was 3 and 4 times more than pure PU, respectively. Moreover, the glass transition temperature was more than 140°C for the composite polyurethane/carbon fiber and 110°C for the PU pure.
Inconsciente e instinto de morte: um itinerário do debate inicial de Deleuze com a psicanálise
(Universidade Federal de São Carlos, 2013-04-18) Sanches, Aline; Simanke, Richard Theisen; https://lattes.cnpq.br/5431145327759147; https://lattes.cnpq.br/0570819174001324
Masochism: Coldness and Cruelty, published in 1967 by Deleuze criticizes psychoanalysis for sustaining the false notion of sadomasochism, and proposes a distinction between death instinct and death drive, so that sadism and masochism are regarded as different processes and mutually exclusive. Deleuze relies on Freud s arguments, more precisely on the text Beyond the Pleasure Principle (1920), to conceive the death instinct as a transcendental principle and to differentiate it from its psychic representative, the death drive. Deleuze thus initiates a philosophical investigation around the transcendental field and the pleasure principle. This investigation runs parallel to an intense debate on psychoanalytical theory, and continues during his later works. Deleuze appreciates the freudian suggestion of an unconscious functioning indifferent to the pleasure principle and governed by repetition. He proposes to develop the concept in the form of transcendental synthesis of time. Difference and Repetition (1968) places Freud in a dialogue with other philosophers especially Hume, Bergson and Nietzsche and postulates three transcendental syntheses marked by repetition, or three passive syntheses of time, which are constitutive of the unconscious and independent of the pleasure principle. From Deleuze s philosophical advances, a reevaluation of several psychoanalytical concepts begins, founded on an understanding of the death instinct as the positive and originating principle of the repetition, as the power that engenders thinking in thought under the effect of violence. Logic of Sense (1969) leads this line of investigation to the argument that the senses are produced by the power of the paradoxes and identifies the death instinct with no sense. Some concepts of Freud, Klein and Lacan are included in the composition of a new image of philosophy and of what it means to think. Trying to demonstrate that thought and sense are produced in close relationship with the erogenous body, Deleuze returns to the psychosexual development but now from the perspective of his philosophical concepts, and presents his own version of the genesis and dynamics of the psychological instances. In view of this philosophical course taking by Deleuze, this doctoral research proposed to explore his discussion with psychoanalysis, according to a trajectory outlined by the concept of death instinct along these three works. We demonstrate how Deleuze understands and appropriates of some psychoanalytic concepts, linking them with other concepts of his philosophy. We indicate which issues from psychoanalysis were valued in the composition of a transcendental philosophy of difference. From a systematic exposition of the criticisms and proposals that Deleuze addresses to the psychoanalytical field in this particular period, we carried out a confrontation between Deleuze's philosophical interventions and the original psychoanalytical texts. Ultimately, this research intends to contribute to a discussion about the pertinence, coherence and relevance of this debate for both domains.
Biotecnologia aplicada à segurança pública: estudo e adequação do método da ninidrina para revelação de impressões digitais em superfícies porosas
(Universidade Federal de São Carlos, 2013-04-18) Alves, Manoel Geralcino; Moreira, Fernando Manuel Araújo; https://lattes.cnpq.br/1809254923092721; https://lattes.cnpq.br/3512454094144958
Several works have been done worldwide and are dedicated to the advancement of software that enables the comparison and reading of fingerprints. Literature shows several works related to the development of scientific techniques that allow the improvement in the collection and disclosure of fingerprints left at crime scenes. Some of those techniques are based on the use of high-tech materials and devices, such as gold nanoparticles and thin films made of copper and gold. However, the cost of these techniques is very high for everyday use, especially when considering the financial budgets for police apparatus in developing countries. Attempting to improve economically such viable and efficient techniques in order to permit the disclosure of latent fingerprints left at crime scenes, this work aims the studying and development of the ninhydrin colorimetric method, by performing numerous tests on fingerprints deposited on porous surfaces, such as paper and walls. Once confirmed the viability of ninhydrin employment, both in laboratory and on-site, and also having adjusted the optimum temperature for rapid revelation; this study provides the use of image-processing software, enabling the expert to compare, in real time, even at the site of criminal traces, the fingerprint image found with the official registry database, thus, obtaining the identity of the offender within a short period of time.
Estudo da alumina anódica porosa como sensor para diferentes gases
(Universidade Federal de São Carlos, 2013-04-18) Guerreiro, Haroldo de Almeida; Chiquito, Adenilson José; https://lattes.cnpq.br/7087360072774314; https://lattes.cnpq.br/1014103626919593
In this project we studied the porous anodic alumina as a possible application in gas sensors with high sensitivity. Initially we seek a configuration of anodic porous alumina (PA) and the type of gas or vapor in which both matched with great sensitivity by observing the photoluminescence of this material. Furthermore we sought to understand the mechanism of detecting the substance to a broader reach and optimizing the use of alumina sensor. A manufacturing already well tested with oxalic acid, only changing the anodization time for the same voltage or current density, was adopted for a small variation of samples with good ordering. Samples were also produced with and without pore opening. The optical properties of the porous film thus obtained were investigated by photoluminescence (PL) emitted perpendicularly to these pores, while the film was subjected to a controlled atmosphere of vapor of ethanol or methanol. The control parameters of temperature and vapor concentration was possible by the construction and use of a thermostated cell adapted to a spectrofluorimeter. The spectrum of each sample was monitored with time since deposition of alcohols in the cell was made with micro-syringe into the liquid phase and then evaporate. This perpendicular direction of luminescence emission of alumina allowed the oscillation of the already known PL presents peaks with much more defined and so much more resolution for changes in wavelength. Furthermore, it expressed the presence of the TE and TM modes separately in luminescence for some samples made at a higher concentration of oxalic acid in the electrolyte. The sensitivity to ethanol vapor for this PL technique allows detection of ethanol concentrations much smaller than the other until now achieved by using porous silicon. Based on studies about the source of the luminescence of the material and the construction of the interference pattern produced by the film type Fabry-Perot, a hypothesis was constructed for the modification of luminescence by ethanol vapor. Adsorption of molecules of ethanol/methanol by its hydroxide OH-, in the color centers F+ along the surfaces of the pores, modifies the average longitudinal position of the sources of luminescence in a critical geometry (near total internal reflection), which changes rapidly the reflectivity of the interface pores/air, altering the entire Fabry-Perot system for this adopted configuration, i.e., PL perpendicular to the pores. The simple change of the luminescence emission from frontal to lateral direction of the film provided an peak oscillation with lasers devices width, without the need to optically confine this film, as in the case of porous silicon sensors. This configuration may have contributed to or be reason for the great sensitivity (relative to the optical porous sensors for ethanol as the porous silicon) as it uses the part of the luminescence that interacts with more pores exposed to ethanol vapor. The reversible behavior and with better response just at room temperature, qualifies the PA system for construction of curves calibration, as well for various types of use in sensor which interfere very little in vapor concentration. The temporal behavior of the spectrum of a sample, under ethanol vapor, may be due to a rapid change in reflectivity of the interface pores/air for this selected PL "grazing", at an angle close to the internal total internal reflection. The change in reflectivity for this type of Fabry- Perot system and confined causes changes in both the shape of the spectrum oscillation, similar to the change in the coefficient of finesse, as in the displacement of the peak position in wavelengths.