En este trabajo se analizó la factibilidad de alcanzar los límites de descarga de efluentes impuestos por el DSN°90/200, a través, de la evaluación de alternativas de remoción biológica de nutrientes que permitan cumplir con los requerimientos de calidad y/o conlleven optimizar el funcionamiento de los sistemas de tratamiento de aguas servidas.

Para discutir os efeitos magneto-óticos nos calcogenetos de Eu desenvolvemos uma expressão geral para a polarizabilidade de um sistema onde as transições eletrônicas importantes sao de orbitais localizados (orbitais 4f) para estados itinerantes (estados de Wannier 5dt2g). Tratamos em detalhe os elementos de matriz do operador dipolo elétri co levando em conta que o orbital 4f é um estado de muitas partículas. Incluimos explicitamente (numa aproximação simples) nos estados intermediários o potencial coulombiano criado pela lacuna no estado localizado 4f. Apresentamos um cálculo numérico da constante de Verdet e do deslocamento de fase Voigt (fases paramagnética e ferromagnética), dicro! smo circular e linear (fase ferromagnética)para o EuSe. Nosso resultado para a constante de Verdet concorda razoavelmente bem com os resultados experimentais e permite-nos estimar o valor da integral radial (4f|r|5d)~4x10-9cm. / To discuss the magneto-optical effects in the Eu chalcogenides we derive a general expression for the polarizability of a system in which the important electronic transitions are from localized to itinerant orbitals. This expression is applied to a model system in which the electronic transitions take place from a 4f orbital to a 5dt2g Hannier orbital centered at the same cell. We treat in detail the matrix elements of the electric dipole operator taking into account the many-body character of the 4f shell. The Coulow) potential of the intermediate state localized hole is included explici tely vli thin a simple approximation. We present a numerical calculation of the frequency dependent, Verdet constant and Voigt phase shift (paramagnetic and ferromagnetic phases), circular and linear dichroism (ferromagnetic phase) for the EuSe. The fittin~ of the Verdet constant to the experimental results is fairly good and allmv us to estimate the value of the integral (4flrl5d)~4x10-9cm.

Para discutir os efeitos magneto-óticos nos calcogenetos de Eu desenvolvemos uma expressão geral para a polarizabilidade de um sistema onde as transições eletrônicas importantes sao de orbitais localizados (orbitais 4f) para estados itinerantes (estados de Wannier 5dt2g). Tratamos em detalhe os elementos de matriz do operador dipolo elétri co levando em conta que o orbital 4f é um estado de muitas partículas. Incluimos explicitamente (numa aproximação simples) nos estados intermediários o potencial coulombiano criado pela lacuna no estado localizado 4f. Apresentamos um cálculo numérico da constante de Verdet e do deslocamento de fase Voigt (fases paramagnética e ferromagnética), dicro! smo circular e linear (fase ferromagnética)para o EuSe. Nosso resultado para a constante de Verdet concorda razoavelmente bem com os resultados experimentais e permite-nos estimar o valor da integral radial (4f|r|5d)~4x10-9cm. / To discuss the magneto-optical effects in the Eu chalcogenides we derive a general expression for the polarizability of a system in which the important electronic transitions are from localized to itinerant orbitals. This expression is applied to a model system in which the electronic transitions take place from a 4f orbital to a 5dt2g Hannier orbital centered at the same cell. We treat in detail the matrix elements of the electric dipole operator taking into account the many-body character of the 4f shell. The Coulow) potential of the intermediate state localized hole is included explici tely vli thin a simple approximation. We present a numerical calculation of the frequency dependent, Verdet constant and Voigt phase shift (paramagnetic and ferromagnetic phases), circular and linear dichroism (ferromagnetic phase) for the EuSe. The fittin~ of the Verdet constant to the experimental results is fairly good and allmv us to estimate the value of the integral (4flrl5d)~4x10-9cm.

Orientador: Hugo Enrique Hernandez Figueroa / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-03T20:57:56Z (GMT). No. of bitstreams: 1 Oliveira_LucianoPradode_M.pdf: 882154 bytes, checksum: 50a64e4d365accdfb6a88a03078e223a (MD5) Previous issue date: 2004 / Mestrado

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Electrostatic charge generation is unavoidable in gas-solid fluidized beds due to the repeated particle-particle and particle reactor wall contacts and separations. In industrial operations such as in polyethylene production this phenomenon results in the significant problem of reactor wall fouling, known as “sheeting”. To better understand the underlying charging mechanisms involved in gas-solid fluidized beds in an attempt to eliminate and/or reduce the effect a novel on-line electrostatic charge measurement technique was developed, which concurrently provided information on both the degree of fluidized bed electrification and reactor wall fouling. A Faraday cup replaced the windbox of the fluidized bed while another cup was placed at the top of the column. The distributor plate was uniquely designed for the systematic removal of bed particles and those adhered to the column wall for their charge measurement with the bottom Faraday cup, and the charge of the entrained particles was measured by the top Faraday cup. This is the first study which allowed the charge measurement of particles in the bulk of the bed, particles adhered to the column wall, and those entrained, simultaneously. In addition, this method uniquely permitted the evaluations of the degree of reactor wall fouling under different operating conditions. An experimental program was designed to investigate the influence of bed hydrodynamics (fluidizing gas velocity and particle size), fluidization column wall material, and the addition of different solid additives. Fluidizing particles were polyethylene resin from an industrial reactor. Bi-polar charging was observed where the elutriated particles were oppositely charged compared to those in the bulk of the bed and those adhered to the column wall. Particles within the wall coating were also found to be bi-polarly charged. With the resin tested as received, a certain sized particles (350-575 µm) adhered to the column wall. The specific charge of the particles near the column wall was found not to be a definite indication of the amount of wall fouling. Increasing the gas velocity promoted wall fouling and elevated the charge density of the particles within both bubbling and slugging flow regimes. The effect of solid additive injection was examined with two static drivers known to reduce wall fouling in industrial operations, a deactivated catalyst, and the catalyst support. It was found that the catalyst promoted, while one of the static drivers reduced wall fouling.

Le laboratoire LT2C utilise depuis quelques années un procédé sol-gel basse température pour développer un matériau magnéto-optique composite parfaitement compatible avec les technologies d’optique intégrée sur verre. Néanmoins, la qualité actuelle du matériau ne permet pas son utilisation dans l’intégration des composants à effets non-réciproques. Dans le but d’exalter les effets magnéto-optiques et le facteur de mérite du matériau, le laboratoire LT2C s’est orienté vers sa structuration 3D en adaptant une approche basée sur les opales. Cette dernière consiste à fabriquer des opales directes à partir de l’auto-arrangement de microbilles de polystyrène sur un substrat de verre. Les opales sont ensuite infiltrées par une solution sol-gel dopée par des nanoparticules magnétiques de ferrite de cobalt. Après traitement thermique, le polystyrène est dissout dans l’acétate d’éthyle pour obtenir une structure 3D formée de trous d’air dans une matrice de silice dopée. Dans ce cadre, l’objectif des travaux de cette thèse consiste tout d’abord à optimiser au mieux la procédure d’élaboration des opales afin d’améliorer leur qualité structurelle et magnéto-optique. Ensuite, il consiste à réaliser une étude systématique des effets magnéto-optiques dans ces structures 3D pour investiguer le comportement spectral de l’effet Faraday, et ainsi qualifier les modifications apportées au facteur de mérite. Une analyse des images MEB et une caractérisation optique montrent que notre méthode d’élaboration conduit à la fabrication d’opales de bonne qualité structurelle et optique. Les mesures de rotation et d'ellipticité Faraday en fonction du champ magnétique appliqué présentent des cycles d’hystérésis, et mettent en évidence un effet non-réciproque, ce qui surligne le caractère magnéto-optique des opales inverses dopées. Une étude spectrale systématique des effets magnéto-optiques dans ces structures 3D montre deux pics et une atténuation de rotation et d’ellipticité Faraday, respectivement en bords et au centre de la BIP. Cependant, ces modifications spectrales significatives ne conduisent pas à une exaltation de la valeur du facteur de mérite. Cela est principalement dû aux défauts structurels qui diminuent le niveau de transmission de l’opale inverse dopée par rapport la couche de référence / LT2C laboratory uses since recent years a low temperature sol-gel process to develop a magneto-optical composite material that is perfectly compatible with glass integrated optics. However, due to an actual low figure of merit, this material cannot be embedded on integrated non-reciprocal devices. In order to exalt the magneto-optical effects and figure of merit, the LT2C laboratory adopted a process based on opals to 3D structure the material. The selected process consists in elaborating direct opals by self-assembling monodisperse polystyrene microspheres on glass substrate. Those opals are then impregnated with a homogeneous solution of sol-gel silica precursors doped with cobalt ferrite nanoparticles. Resulting samples are later oven dried for 1 hour at 90°C. Finally, polystyrene spheres are dissolved in ethyl acetate to obtain a 3D structure formed by air voids in doped silica matrix. In this context, the objective of this thesis is to optimize the fabrication process of opals in order to improve their structural and magneto-optical quality. Furthermore, it consists in making a systematic study of the magneto-optical effect in these structures in order to investigate the spectral behavior of the Faraday effect and thus quantify the figure of merit. Analysis of SEM images and optical characterization prove that our elaboration process leads to the fabrication of opals with good structural and optical quality. Measurements of Faraday rotation and ellipticity as a function of applied magnetic field show hysteresis loops with an unambiguous non-reciprocal behavior. These observations highlight the magneto-photonic character of the doped inverse opals. A systematic spectral study of the magneto-optical effect in these 3D structures displays two peaks and an attenuation of Faraday rotation and ellipticity, respectively at the edges and the center of the photonic band gap. However, these significant spectral modifications do not increase the value of figure of merit. This ascertainment is primarily due to structural defects that lower the transmission magnitude of the doped inverse opals in comparison to a magneto-optical reference monolayer

Memoria para optar al título de Ingeniero Civil Matemático / El presente es un estudio del fenómeno de la Inestabilidad de Faraday en una celda de Hele-Shaw especialmente delgada lo que provocó histéresis en el cambio de estado de equilibrio. Este escrito consiste de tres capítulos. El primero es teoría de la resonancia y el segundo y tercero describen dos experimentos en donde se generan patrones sobre la superficie de un fluido en una celda de Hele-Shaw sometida a vibración. En el primer capítulo se explica el concepto de resonancia en un péndulo en casos con y sin roce, luego se pasa al concepto de resonancia paramé- trica, primero en un péndulo y luego en una cadena de péndulos en donde el pivote tiene un movimiento sinusoidal vertical, llegando a obtener ecuaciones de amplitud de estos fenómenos oscilatorios. En el segundo capítulo se estudia experimentalmente la formación de patro- nes en un fluido contenido en una celda Hele-Shaw vibrada verticalmente. Se usa una celda de acrílico para que sea transparente y se pueda ver el patrón y grabar con una cámara rápida puesta a un lado del montaje. En el tercer capítulo se estudia lo mismo que en el capítulo anterior pero inclinando el sistema en un pequeño ángulo (lo que produce un efecto de agregar ruido al sistema) y en vez de una cámara puesta a un lado se usa un láser que se refleja en la superficie del fluido y luego llegando a una pantalla. Se observa la figura que hace el láser en la pantalla. / CMM - Conicyt PIA AFB170001

Knowledge of the coronal magnetic field is crucial for understanding (1) the heating mechanism(s) of the solar corona, (2) the acceleration of the fast solar wind, and (3) the structure and dynamics of coronal mass ejections (CMEs). Observation of Faraday rotation (FR) is one of the best remote-sensing techniques for determining plasma properties in the corona and can provide information on the plasma structure of a CME shortly after launch, shedding light on the initiation process. I used the Karl G. Jansky Very Large Array (VLA) to make sensitive Faraday rotation measurements to investigate the general plasma structure of the corona, properties of coronal plasma inhomogeneities and waves, and transients associated with coronal mass ejections. To enhance my measurements of FR transients, I also developed an algorithm in the Common Astronomy Software Applications (CASA) package to mitigate ionospheric Faraday rotation. In August, 2011, I made FR observations at 5.0 and 6.1 GHz of the radio galaxy 3C 228 through the solar corona at heliocentric distances of 4.6 - 5.0 solar radii using the VLA. Observations at 5.0 GHz permit measurements deeper in the corona than previous VLA observations at 1.4 and 1.7 GHz. These FR observations provided unique information on the magnetic field in this region of the corona. My data on 3C 228 provide two lines of sight (separated by 46 arcseconds, 33,000 km in the corona). I detected three periods during which there appeared to be a difference in the Faraday rotation measure between these two closely spaced lines of sight, which I used to estimate coronal currents; these values (ranging from 2.6 to 4.1 GA) are several orders of magnitude below that which is necessary for significant coronal heating (assuming the Spitzer resistivity). I also used the data to determine upper limits (3.3 and 6.4 rad/m⁻²along the two lines of sight) on FR fluctuations caused by coronal waves. These upper limits are comparable to and, thus, not inconsistent with the theoretical models for Alfvén wave heating of the corona by Hollweg et al. (2010). To support the needs of the low frequency radioastronomical community as well as my own research of coronal FR transients, I developed a new calibration algorithm for CASA that uses GPS-based global ionosphere maps of the Total Electron Content (TEC) to mitigate ionospheric Faraday rotation. The Earth's ionosphere introduces direction- and time-dependent effects over a range of physical and temporal scales and so is a major source for unmodeled phase offsets for low frequency radioastronomical observations. It has become common practice to use global ionospheric models derived from the Global Positioning System (GPS) to provide a means of externally calibrating low frequency data. However, CASA, which was developed to meet the data post-processing needs of next generation telescopes such as the VLA and the Atacama Large Millimeter/submillimeter Array (ALMA), did not have the capability to make ionospheric corrections before I implemented this calibration algorithm. I investigated several data centers as potential sources for global ionospheric models and chose the International Global Navigation Satellite System Service data product because data from other sources are generally too sparse to use without additional interpolation schemes. I employed these ionospheric corrections in reducing VLA observations made in August, 2012, at 1 - 2 GHz of a “constellation” of radio sources through the solar corona at heliocentric distances that ranged from 5 - 15 solar radii. Of the nine sources observed, three were occulted by CMEs: 0842+1835, 0900+1832, and 0843+1547. In addition to my radioastronomical observations, which represent one of the first active hunts for CME Faraday rotation since Bird et al. (1985) and the first active hunt using the VLA, I obtained white-light coronagraph images from the LASCO/C3 instrument aboard SOHO to determine the Thomson scattering brightness, BT. BT is proportional to the electron plasma density and provides a means to independently estimate the plasma density and determine its contribution to the observed Faraday rotation. A constant density force-free flux rope embedded in the background corona was used to model the effects of the CMEs on BT and FR. In the case of 0842+1835, the flux rope model underestimated the peak value in BT and did not reproduce the decreasing BT inside the inner cavity region of the CME; however, there was satisfactory agreement between the model and the observed FR. The single flux rope model successfully reproduces both the observed BT and FR profiles for 0900+1832. 0843+1547 was occulted by two CMEs. Therefore, I modeled observations of 0843+1547 using two flux ropes embedded in the background corona. The two flux rope model successfully reproduces both BT and FR profiles for 0843+1547 and, in particular, the two flux rope model successfully replicates the appropriate slope in FR before and after occultation by the second CME and predicts the observed change in sign to FR > 0 at the end of the observing session. I briefly discuss the plasma densities ( 6 - 22 x 10³ cm⁻³) and axial magnetic field strengths (2 - 12 mG) inferred from my models and compare them to the modeling work of Liu et al. (2007) and Jensen et al. (2008), as well as previous CME FR observations by Bird et al. (1985).

Parametric resonance is a particular type of resonance in which a parameter in a system changes with time. A particularly interesting case is when the parameter changes in a periodic way, which can lead to very intricate behavior. This di↵ers from periodic forcing in that solutions are not necessarily periodic. A system in which parametric resonance is realized is when a fluid bath is shaken periodically, which leads to an e↵ective time dependent gravitational force. This system will be used to study the onset of surface waves in a bath with non-uniform topography. A linear model for the surface waves is derived from the Euler equations in the limit of shallow waves, which includes the geometry of the bottom and surface tension. Experiments are performed to compare with the proposed model and good qualitative agreement is found. Another experiment which relies on a shaking fluid bath is that of bouncing fluid droplets. In the case of two droplets the shaking allows for a larger bouncing droplet to attract a smaller moving droplet in a way that creates a bound system. This bound system is studied and shows some analogous properties to quantum systems, so a quantum mechanical model for a two dimensional atom is studied, as well as a proposed model for the droplet-wave system in terms of equations of fluid mechanics.