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Nenhuma / Investigamos neste trabalho as propriedades elétricas e térmicas de 1)compositos resina epóxi/nanotubos de carbono de paredes múltiplas concêntricas (MWNT) manufaturados com 0,1, 0,5 e 1% em massa de MWNT dispersos aleatoriamente na resina; 2)de compósitos reina/buckpaper; 3) de buckpaper (tecido de MWNT).

[pt] A dissertação tem por objetivo propor e validar um sistema gravimétrico para a calibração de medidores de vazão de líquidos. A motivação pela escolha do tema resultou da necessidade identificada junto ao setor de petróleo e gás para assegurar que as medições de vazão demandadas pelo setor sejam rastreáveis a padrões nacionais e satisfaçam as exigências contratuais e regulatórias aplicáveis. A metodologia utilizada permitiu avaliar a confiabilidade metrológica dos instrumentos não-automáticos de pesagem (em conexão ao sistema gravimétrico) e intercomparar, metrologicamente, diferentes alternativas de medição do volume dos reservatórios integrados ao sistema gravimétrico. Os resultados da pesquisa permitiram (i) estimar a confiabilidade metrológica dos instrumentos não-automáticos de pesagem em 0,04 kg para a balança Alfa modelo 3107 e 0,14 g para a balança OHAUS modelo Explorer Pro; e (ii) definir uma faixa de incerteza de 0,02 por cento a 0,05 por cento associada à calibração do sistema gravimétrico, dependendo do volume de fluido de trabalho transferido no processo de calibração. Como conclusão, o sistema gravimétrico para calibração de medidores de vazão de líquidos foi considerado validado à luz das incertezas reportadas, assim contribuindo para o avanço do conhecimento na área da metrologia de vazão. / [en] The objective of this MSc. dissertation is to propose and to validate a gravimetric system for the calibration of flow meters for liquids. The motivation for the choice of this theme resulted from the need identified by the oil and gas sector to ensure that measurements of flow rate demanded by the sector can be traceable to national standards and attend the contractual and regulatory requirements. The methodology used allowed to evaluate the metrological reliability of non-automatic weighing instruments (in connection with the gravimetric system) and compare, metrologically, different options for measurement of volume of reservoirs in connection with the gravimetric system. The research results allowed (i) to estimate the metrological reliability of non-automatic weighing instruments in 0,04 kg for the balance Alfa model 3107 and 0,14 g for the balance OHAUS model Explorer Pro; and (ii) to define an uncertainty range of 0.02 percent to 0.05 percent associated with the gravimetric system, depending of volume of the working fluid transferred in the calibration process. In conclusion, the gravimetric system for calibration of flow meters liquid was considered valid with the reported uncertainties, thus contributing to the advancement of knowledge in the area of flow metrology.

O Distrito Grafitífero Aracoiába-Baturité apresenta depósitos do tipo gnaisse grafitoso (minério disseminado) e veio (minério maciço) com diferentes origens genéticas e com características físicas e ambientes geológicos de formação próprios. O minério tipo gnaisse grafitoso é de origem sedimentar, singenético, com teores de 1,5 a 8% de C, que se distribuem ao longo de duas extensas faixas paralelas, hospedadas na Subunidade Baturité, que constitui um importante metalotecto regional. A associação de grafita metamórfica disseminada em metassedimentos da Sequência Acarápe constitui um geoindicador de antiga bacia sedimentar neoproterozóica e, também, pode ser considerado como zona de geosutura resultante do subsequente fechamento de um oceano primitivo. As rochas desta subunidade correspondem na paleogeografia da Sequência Acarápe aos fácies de sopé de talude e de planície abissal. O minério tipo veio (fluido depositado) é epigenético e, com teores entre 20% e 70% de C, forma corpos tabulares e bolsões, controlados em escala local por estruturas de alívio (falhas, fraturas, zonas de contato, eixos de dobras etc.) que permitiram a percolação de soluções penumatolíticas relacionadas ao corpo plutônico de Pedra Aguda. As variações dos valores das relações entre isótopos estáveis de carbono (δ13C) na grafita do minério disseminado são de -26,72 a -23,52 e do minério maciço de -27,03 a -20,83, revelando sinal de atividades biológicas (bioassinaturas) e permitem afirmar que a grafita das amostras acima são derivadas de matéria orgânica. Foram apresentados os principais guias de prospecção para grafita e testados os seguintes métodos geofísicos: Eletro-Resistividade; GPR - Ground Penetrating Radar; Magnetometria; VLF (Very Low Frequency); e Polarização Induzida Espectral (IPS) / Resistividade (ER). A conjugação dos métodos de Polarização Induzida Espectral (IPS) e Eletro Resistividade (ER) foi o que demonstrou a melhor eficiência. Com relação à determinação do teor de carbono por termogravimetria (ATG), que é o método mais utilizado para este elemento. Verificou-se, que as faixas de queima atribuídas ao carbono no minério do Distrito de Aracoiába-Baturité (340 a 570C e de 570 a 1050C) eram diferentes das faixas do minério de Minas Gerais (350C a 650C e 650C a 1.050C). Esta constatação indica a necessidade de se determinar previamente as faixas de temperatura para cada região pesquisada. / The Aracoiába-Baturité Graphite-bearing District has graphitic gneiss deposits (disseminated ore) and vein (solid ore) with different genetic origins and their own physical characteristics and geological environments. The graphite gneiss ore is of sedimentary, syngenetic origin, with 1.5% to 8% C content, which is distributed along two long parallel belts, hosted in the Baturité Sub-unit, which consists of a major regional metallotect. The association of metamorphic graphite disseminated in metasediments of the Acarápe Sequence consists of a geoindicator of an old Neo-Proterozoic sedimentary basin and also can be considered a geosuture zone, the result of the subsequent closing of a primitive ocean. The rocks of this subunit correspond in the paleogeography of the Acarápe Sequence to the facies of the bottom of a slope and of an abyssal plain. The vein ore (deposited fluid) is epigenetic and, with C contents of between 20% and 70%, forms tabular bodies and pockets, controlled on a local scale by relief structures (faults, fractures, contact zones, fold axes, etc.), which allowed seepage of pneumatolithic solutions relating to the plutonic body of Pedra Aguda. The variations in the values of the ratios between stable carbon isotopes (δ13C) in the graphite of the disseminated ore are -26.72 to -23.52 and of the solid ore -27.03 to -20.83, showing a sign of biological activities (biosignatures), and it can be said that the graphite of the above samples is derived from organic matter. The main prospecting guides for graphite were presented and the following geophysical methods tested: Electro-resistivity (ER); Ground Penetrating Radar (GPR); Magnetometry; Very Low Frequency (VLF); and Spectral Induced Polarization (SIP) / Electro-resistivity (ER). It was found that the combination of the Spectral Induced Polarization (SIP) and Electro-resistivity (ER) methods proved the most efficient. In relation to determining the carbon content using thermogravimetry (TG), which is the most commonly used method for this element, it was found that the bands of burning attributed to the carbon in the ore in the Aracoiába-Baturité District (340 to 570C and from 570oC to 1050C) were different from the bands of the ore in Minas Gerais (350C to 650C and 650C to 1050C). This finding suggests the need to determine beforehand the temperature ranges for each region studied.

Made available in DSpace on 2016-12-23T14:08:10Z (GMT). No. of bitstreams: 1 Marcelo Aiolfi Barone - cap 00 - 01 - 02 - 03 - 04.pdf: 1483841 bytes, checksum: f4e05e25d485e179dfceea82acfc06b7 (MD5) Previous issue date: 2012-10-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho utiliza um protótipo de escala laboratorial do medidor primário pipe prover de modo a avaliar a sua conformidade com os requisitos estabelecidos por normas técnicas e examinar a incerteza da medição da vazão realizados, além de verificar a reprodutibilidade das medições, testes com esferas de diferentes diâmetros, a influência de parâmetros operacionais tais como a variação da pressão de operação e comparação com o teste gravimétrico. O protótipo é feito de tubos plástico com dimensões definidas estatisticamente. Dentro do tubo, uma esfera de elastômero interferente é impulsionada por um escoamento fornecido por uma bomba centrífuga. O sistema de detecção usa sensores de luz infravermelha capaz de detectar a passagem das esferas sem causar interferência ou bloqueio na tubulação. O sistema de aquisição de dados é automático e registra o tempo de trânsito da esfera através de cada pulso de sinal detectado bem como os pulsos gerados por um medidor calibrado tipo turbina, como comparação da avaliação das incertezas de processo utilizando o desempenho da técnica dos sensores infravermelhos / The work uses a laboratory scaled prototype of primary pipe prover flowmeter in order to assess conformity with the requirements established by technical standards and examine the uncertainties of flow measurement performed, besides to check the reproducibility of measurements, tests with spheres of different diameters, the influence of operating parameters such as operating pressure variation and comparison with gravimetric test. The prototype is plastic tubing and considering statically defined dimensions. Inside tubing, an interfering elastomer sphere is driven by flow provided by a centrifugal pump. The detection system uses infrared light sensors able to detect the spheres passage causing pipeline interference or blockage. The acquisition data system is automatic and records the sphere transit time through each pulse signal detected as well as the pulses generated by a calibrated turbine meter, as comparison of the evaluation of process uncertainties using the technique performance with infrared sensors

The fields of health care and environment control have an increasing demand for sensors able to detect low concentrations of specific molecules in gaseous or liquid samples. The recent introduction of microfabricated devices in these fields gave rise to sensors with attractive properties. A cutting edge technology is based on guided acoustic waves, which are perturbed by events occurring at the nanometer scale. A first part of the thesis investigates the Love mode waveguide, a versatile structure in which a thin film is guiding the acoustic wave generated in a piezoelectric substrate. A systematic analysis of its sensitivity was obtained using a transmission line model generalized to discriminate the rigid or viscous nature of the probed layers. We developed a novel integrated combination of the Love mode device with a Surface Plasmon Resonance optical sensor to quantify the thickness and the composition of soft layers. The electromagnetic interferences in the recorded signal were modeled to determine the phase velocity in the sensing area and to provide new mechanisms for an enhanced sensitivity. The experimental aspects of this work deal with the fabrication, the important issue of the packaging and the sensitivity calibration of the Love mode biosensor. A second part of the thesis investigates nanocrystalline diamond under the form of a thin film membrane suspended to a rigid silicon frame. The high mechanical and chemical resistance of nanocrystalline diamond, close to single-crystal diamond, open ways to membrane based acoustic sensors such as Flexural Plate Wave and thin Film Bulk Acoustic Resonators (FBAR). A novel dynamic characterization of the thin film is reported and the properties of composite FBAR devices including a diamond thin film membrane and a piezoelectric aluminum nitride layer are assessed using the perturbation theory. This study is applied to evaluate the high sensing potential of the first prototype of an actual diamond-based composite FBAR.

Engineering directly impacts current and future regulatory policy decisions. The foundation of air pollution control and air pollution dispersion modeling lies in the math, chemistry, and physics of the environment. Therefore, regulatory decision making must rely upon sound science and engineering as the core of appropriate policy making (objective analysis in lieu of subjective opinion). This research evaluated particulate matter and ammonia concentration data as well as two modeling methods, a backward Lagrangian stochastic model and a Gaussian plume dispersion model. This analysis assessed the uncertainty surrounding each sampling procedure in order to gain a better understanding of the uncertainty in the final emission rate calculation (a basis for federal regulation), and it assessed the differences between emission rates generated using two different dispersion models. First, this research evaluated the uncertainty encompassing the gravimetric sampling of particulate matter and the passive ammonia sampling technique at an animal feeding operation. Future research will be to further determine the wind velocity profile as well as determining the vertical temperature gradient during the modeling time period. This information will help quantify the uncertainty of the meteorological model inputs into the dispersion model, which will aid in understanding the propagated uncertainty in the dispersion modeling outputs. Next, an evaluation of the emission rates generated by both the Industrial Source Complex (Gaussian) model and the WindTrax (backward-Lagrangian stochastic) model revealed that the calculated emission concentrations from each model using the average emission rate generated by the model are extremely close in value. However, the average emission rates calculated by the models vary by a factor of 10. This is extremely troubling. In conclusion, current and future sources are regulated based on emission rate data from previous time periods. Emission factors are published for regulation of various sources, and these emission factors are derived based upon back-calculated model emission rates and site management practices. Thus, this factor of 10 ratio in the emission rates could prove troubling in terms of regulation if the model that the emission rate is back-calculated from is not used as the model to predict a future downwind pollutant concentration.

The fields of health care and environment control have an increasing demand for sensors able to detect low concentrations of specific molecules in gaseous or liquid samples. The recent introduction of microfabricated devices in these fields gave rise to sensors with attractive properties. A cutting edge technology is based on guided acoustic waves, which are perturbed by events occurring at the nanometer scale. A first part of the thesis investigates the Love mode waveguide, a versatile structure in which a thin film is guiding the acoustic wave generated in a piezoelectric substrate. A systematic analysis of its sensitivity was obtained using a transmission line model generalized to discriminate the rigid or viscous nature of the probed layers. We developed a novel integrated combination of the Love mode device with a Surface Plasmon Resonance optical sensor to quantify the thickness and the composition of soft layers. The electromagnetic interferences in the recorded signal were modeled to determine the phase velocity in the sensing area and to provide new mechanisms for an enhanced sensitivity. The experimental aspects of this work deal with the fabrication, the important issue of the packaging and the sensitivity calibration of the Love mode biosensor. A second part of the thesis investigates nanocrystalline diamond under the form of a thin film membrane suspended to a rigid silicon frame. The high mechanical and chemical resistance of nanocrystalline diamond, close to single-crystal diamond, open ways to membrane based acoustic sensors such as Flexural Plate Wave and thin Film Bulk Acoustic Resonators (FBAR). A novel dynamic characterization of the thin film is reported and the properties of composite FBAR devices including a diamond thin film membrane and a piezoelectric aluminum nitride layer are assessed using the perturbation theory. This study is applied to evaluate the high sensing potential of the first prototype of an actual diamond-based composite FBAR.

In the past decade, tremendous progress has been made in organic field effecttransistors. Fused oligothiophenes and anthracene molecules are fascinatingmacromolecules having unique optoelectronic properties. These compounds are successfully employed as active components in optoelectronic devices including field effect transistors. Our goal is to design and synthesize conjugated molecular materials, which are highly functionalized through structural modifications in order to enhance their electronic, photonic, and morphological properties. The main desire is to synthesize novel organic fused-arenes having efficient charge carrier mobilities, as well as to optimize optical properties for organic field effect transistors (OFETs). Novel series of fused arene molecules of 9,10-di(thiophen-3-yl)anthracene (1), trans-2,5-(dianthracene-9- vinyl)thiophene (2), trans-5,5’-(dianthracene-9-yl)vinyl)- 2,2’-bithiophene (3), 5,5’-di(2 thiophene)-2,2’-bithiophene (4) , 9,10-(divinyl)anthracene core with 1- phenylcarboxypyrene (6) and polymers of poly(anthracene-co-bithiophene) (5) and poly(anthracene) (7) have been synthesized as promising materials for organic field effect transistors (OFETs). These compounds were confirmed and characterized by 1H-NMR, FT-IR, and elemental analysis. Their optical, thermal, and electronic properties were investigated using UV-Vis and photoluminescence spectroscopy, and thermogravimetric analysis respectively. Future studies will focus on evaluating OFETs performance of these material.