Group 13 metals play a pivotal role in many areas of research ranging from materials to environmental chemistry. An important facet of these disciplines is the design of discrete molecules that can serve as functional materials for electronics applications and modeling studies. A solution-based synthetic strategy for the preparation of discrete Group 13 hydroxo-aquo tridecamers with utility as single-source precursors for amorphous functional thin film oxides is introduced in this dissertation. Several techniques including 1H-Nuclear Magnetic Resonance (NMR) spectroscopy, 1H-Diffusion Ordered spectroscopy, Solid-state NMR, Dynamic Light Scattering, and Raman spectroscopy are used to acquire structural information necessary for understanding the nature of these precursors in both the solid and solution phases. The dynamic behavior of these compounds has encouraged additional experiments that will pave the way for new studies with significant importance as the environmental ramifications of these compounds become relevant for future technologies. This dissertation includes previously published and unpublished co-authored material.

Submitted by Caroline Falcao (caroline.rfalcao@ufpe.br) on 2017-06-07T16:16:38Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2011-Dissertacao-JacyaraMariaVieira.pdf: 2851659 bytes, checksum: 9717f3b39ee72a29e0b2d9b0da8e4807 (MD5) / Made available in DSpace on 2017-06-07T16:16:38Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) 2011-Dissertacao-JacyaraMariaVieira.pdf: 2851659 bytes, checksum: 9717f3b39ee72a29e0b2d9b0da8e4807 (MD5) Previous issue date: 2011-09 / Ointeresse pelos estudos de biocombustíveis produzidos a partir de óleos vegetais iniciou-sena década de 80, em 1989,por Rudolf Diesel,com a utilização do óleo de amendoim. Por apresentar um teor de 54% de óleo extraído da amêndoa de seu fruto, a oiticica integra uma das novas fontes de oleaginosas estudadas para inserção na matriz energética brasileira para produção de biodiesel. Éuma árvore que pertence a família das Crysobalanaceae,é típica do semiárido nordestino e pode ser encontrada nos estados do Ceará, Paraíba, Piauí e Rio Grande do Norte.Porém, este óleo apresenta característicadeviscosidade eacidez elevadaso que impede seu uso direto na transesterificação. Para tratar a acidez e viscosidade foi realizada uma purificação por degomagem seguida de uma esterificação ácida. O óleo de oiticica apresentou excelente decaimento de acidezapós os tratamentos de degomagem e esterificação aplicados. A degomagem reduziu a acidez em 54,13%(de 15,24 para 6,99 mgKOH/g)e após a esterificação esta acidez foi reduzida em 75,8%(de 15,24 para 2,88mgKOH/g), mostrando a eficiência do processo e a possibilidade de utilização na produção de biodiesel. O óleo bruto e os resultadosde óleo degomado e esterificado foram caracterizadospor análises termogravimétricas, densidade, viscosidade, índice de acidez e índice de saponificação.Com os resultados de densidade e acidez observou-se a influencia do tipo de degomagem utilizadanestes, sendo a aquosa a que apresentou melhor resultado. No processo de esterificação foi analisado a relação álcool:óleo (6:1 e 12:1), o tipo de álcool (metanol e Etanol), o percentual de catalisador (0,1 e 0,7%) e a temperatura (35°C e 75°C) mostrando que a relação álcool óleo e o percentual de acidez influenciam na esterificação sendo a melhor curva de decaimento com 12:1 álcool:óleo, 0,7% de catalisador e 75°C e metanol. Concluindo que estes parâmetros influenciam diretamente no processo sendo a relação álcool:óleo e o percentual de catalisador os parâmetros mais importantes do processo. / Studies of biofuels produced from vegetable oils have emerged in the 1989's by Rudolf Diesel, the use of peanut oil. The Oiticica is atreefamily of Crysobalanaceae, is typical of semi-arid Northeast and can be found in the states of Ceara, Paraiba, Piaui and Rio Grande do Norte. The oil is extracted from the kernel of its fruit, and this corresponds to 54% oil content. The myrtle is inserted between the new sources of oil studied for inclusion in the Brazilian energy for biodiesel production due to high content of oil extracted from its seed. However, this oil has a characteristic viscosity and high acidity which prevents direct use in the transesterification. To treat the acidity and viscosity was performed followed by purification by a degumming acid esterification. Myrtle oil showed excellent acidity decay after degumming and esterification treatments applied. The degumming reduced the acidity in 54,13% and after this acid esterification was reduced by 81,10%, showing the efficiency of the process and the possibility of use in biodiesel production. The crude oil and the results of degummed and esterified were characterized by thermogravimetric analysis, density, viscosity, acid value and saponification index. The results of density and acidity influenced the type used for degumming, and the aqueous presented the best result. In the process of esterification was analyzed the alcohol: oil (6:1 and 12:1), the type of alcohol (methanol and ethanol), the percentage of catalyst (0.1 and 0.7%) and temperature (35 ° C and 75 ° C) showing that the alcohol percentage of oil and acidity influence the esterification being the best decay curve with 12:1 methanol: oil, 0.7% catalyst and 75 ° C and methanol. Concluding that these parameters directly influence the process and the alcohol: oil and the percentage of catalyst the most important parameters of the process.

The modern critics offer two different approaches regarding characterization in Golden Age Spanish theatre. The first approached, used by the majority of literary critics, consists in assuming that that the reader has to discover something that is hidden in the text. According to this approach, stage characters are creations of the author who, like a great architect, produces personalities that the reader has to discover. On the other hand, there are critics who claim that the characters have to be constructed by the reader. (José María Ruano de la Haza, Víctor Dixon). The main goal of my thesis is to elaborate a methodology for the constriction of dramatic characters and apply it to the six “prototypical” characters described in the classic study by Juana de José Prades.

Forward osmosis (FO) is an osmotically driven process that uses a high concentration draw solution to pull water across a semipermeable membrane from a feed solution. Wastewater, seawater, or other contaminated water sources may be used as a feed solution. In FO, the final product is not clean water but a diluted draw solution. However, FO may be combined with another process, e.g. reverse osmosis (RO). The resulting hybrid process offers advantages compared to the RO process in, for example, seawater desalination. Thin-film composite (TFC) membranes have been used in pressurized processes such as RO due to their thick porous support layer and their ability to endure high hydrostatic pressures. However, the presence of a thick porous layer is detrimental for FO processes. It is responsible for the internal concentration polarization (ICP) inside the membrane, reducing the osmotic driving force and the overall water flux. The characterization of membranes in FO applications is key for understanding how different intrinsic parameters affect membrane performance. In this work, a previously developed methodology for characterizing TFC membranes was improved. Experimental data was obtained from a laboratory-scale FO system, and the experimental data was used to determine three intrinsic transport parameters, namely the water permeance, the salt permeance and the porous layer structural parameter. With this method, the characterization of TFC membranes can be achieved based exclusively on FO data. A sensitivity analysis has highlighted the impact of the intrinsic transport parameters on an FO membrane performance.

Isobutylamine N-hydroxylase (IBAH) and flavin reductase (FRED) from Streptomyces viridifaciens are part of a two-component flavin-dependent monooxygenase enzyme system that catalyze the conversion of isobutylamine (IBA) to isobutylhydroxylamine (IBHA), a key step in the formation of valanimycin, an azoxy antibiotic. In this work, we present the over-expression, purification and biochemical characterization of this two-component enzyme system. IBAH and FRED were expressed and purified to homogeneity as separate proteins. FRED exhibited the oxidoreductase activity by catalyzing the oxidation of NADPH. The hydroxylation activity of IBAH was confirmed using liquid chromatography – mass spectrometry (LC-MS). Steady state kinetic data showed an oxidation activity of the monooxygenase component which proceeded at 1.97 ± 0.06 s⁻¹ as measured from oxygen consumption and in product formation, the rate was 0.012 ± 0.001 s⁻¹ , suggesting a high degree of uncoupling between product formation and oxygen consumption. In pre-steady state kinetic characterization studies, the FRED-catalyzed reduction of FAD by NADPH occurred at a rate of 10.0 ± 0.2 s⁻¹ and the KM was 490 ± 40 µM. The rate of reduction was ~1.5-fold decreased in the presence of substrate IBA whiles the KM was 500 ± 50 µM. NADH showed a markedly reduced rate of reduction with a kred of 0.34 ± 0.03 s⁻¹ with an apparent KM of 3000 ± 500 µM. The rate of flavin re-oxidation in the absence of monooxygenase IBAH was 4.79 × 10⁻⁹ M-1 s⁻¹. Our results suggest a reaction mechanism for the IBAH monooxygenase system controlled by the oxidation half reaction that may be modulated by a complex formation between the reductase and monooxygenase components. / Master of Science in Life Sciences

Software Defined Radios (SDRs) are systems in which components such as filters, modulators, demodulators, etc., typically implemented in hardware are instead implemented in software. Thus, SDR systems shift signal processing from analog to digital domain. The signal processing is performed in reconfigurable devices like General Purpose Processors (GPP) or Field Programmable Gate Arrays (FPGA). The resulting flexibility of SDR systems brings in many advantages to wireless communications such as improved interoperability, adaptation capability and more future-proof hardware. Various prototype/laboratory friendly hardware are available such as Universal Software Radio Peripherals (USRPs), developed by Ettus Research, which in combination with software interfaces such as GNU Radio can be used to design and implement a Software Defined Radio(SDR) system. This has in turn enabled numerous research opportunities and advancements in field of wireless communication. However one major drawback of these simple USRP devices is that they are un-calibrated in terms of power or voltage and hence give the results in relative terms/counts. This poses a disadvantage in real world scenarios where parameters such as power measured in milliwatts or dBm, are used to design, implement, and test devices and systems and to collect and interpret experimental results. Lack of connectivity with these metrics leads to the USRP devices being confined to proof of concept implementation and demonstrations, and limits their utility for experimentation. In this thesis an attempt has been made to calibrate the USRPN210 (with WBX daughter board) devices and derive some calibration factors that would help relate the experimental results obtained from the USRP and GNU Radio combination to real world metrics. This also makes the result-set clearer and easily understandable. Several experiments were conducted to understand and characterize the performance of the USRP under different conditions. Experiments such as determination of 1-dB compression point, Third order intercept point helped understand the linearity range of the device under transmitter and receiver operations. The 3rd order input intercept point for USRPN210 device with WBX board with calibration was found to be around 0.25 dBm, which is closer to the expected value of 0 dBm at 400 MHz. Amplitude and frequency stability tests over the operational frequency range of the daughter board helped to note if change in frequency produced any variation in the received or transmitted power. Also variation with respect to gain helped derive a reference table for transmitted power, which could be used in for future experiments. Conducting these experiments over a sample of 10 USRPs helped in obtaining standardized values and benchmarking them. The factors obtained were also used in some experiments like path loss modeling, position location estimation in order to determine their effectiveness and impact on such applications. Although, these factors obtained may not be directly applicable to all USRP devices, as in any analog circuitry, and also since they are conducted relative to some specific applications such as the predefined spectrum analyzer utility of GNU Radio (UHD_FFT.grc), they do help to understand the basis of derivation of calibration metrics resulting from the various experiments and also provide a platform for future work in this area to obtain more uniform and globally acceptable results. All photos by the author unless cited, 2014. / Master of Science

Laser-induced breakdown spectroscopy (LIBS) has been established as a rapid, in situ, and real-time spectroscopic analytical technique for material characterization. It is very handy for the study of all kinds of materials irrespective of their state. After being used for a Mars mission, LIBS has gained global attention and many scientific researches are investigating its applications. The main objective of this dissertation is to study the possibility of using laser spectroscopic sensing techniques for material characterization and if possible, to develop methodologies. Studying molecular emission spectra for elemental analysis is a relatively new trend in the spectroscopic field. Molecular emission from SrCl and SrO observed in LIBS spectra were analyzed and compared with atomic emission from Sr. Calibration models were developed using both molecular bands and atomic spectral peaks. The determination of nutritional elements in crops, vegetables, and fruits is very important to evaluate their nutritional status. The LIBS technique was applied to identify the nutritional elements present in cauliflower and broccoli, and to evaluate the difference between organic and conventional vegetables in terms of nutritional elements. Principal component analysis (PCA) and one-to-one comparison using Student's t-test were employed for discrimination between organic and conventional vegetable flowers. Early iron and steel production in the state of Pennsylvania (United States) mostly utilized blast furnaces that were operated by charcoal as a primary fuel, followed by anthracite, then coke. The process left behind a by-product known as blast furnace slag. Blast furnace slag, non-metallic in nature, appears to have various industrial applications. LIBS was used for the analysis of charcoal blast furnace slags and qualitative as well as quantitative analyses were demonstrated. To evaluate the possibility of using the LIBS technique to detect and quantify rare earth elements, three consecutive studies were executed. Firstly, pure oxides of six rare earth elements were studied and then real samples directly taken from natural ores were analyzed. In the third step, two rare earth elements (Eu and Yb) in aqueous solutions were studied by underwater LIBS and the pressure effect on the plasma emission is discussed.

A test system was commissioned to characterize commercial thermoelectric modules to be used in the Pizza Oven Waste Energy Recovery (POWER) system for Pizza Pizza restaurants. The objective of this testing was to obtain and classify the thermoelectric material parameters of the Bi2Te3 within commercial thermoelectric generator (TEG) modules. These parameters consisted of the Seebeck coefficient, the thermal conductivity and the electrical resistivity. Together they provide the normalized figure of merit for the thermoelectric material which is a performance indicator for energy efficiency at a given operating temperature. From this research, a two phase methodology was developed that was able to extract the desired values from these modules. Material quality and device composition was first assessed with tools such as SEM and EDS. During this phase, dimensional and elemental data was gathered and a finite element model was constructed to ensure the validity of the primary selected test method for this research which was the Harman technique. The results obtained with this method were all three of the aforementioned thermoelectric parameters as well as a direct measurement of the figure of merit. Thermal and electrical losses for the TEG1B-12610-5.1 module were characterized from room temperature to 200°C using this process. It was determined that the thermal losses were more dominant and could be approximated using a function of T4 to within 1% of their calculated values. This process can be applied to any model of TEG to forecast these losses. To assist with future research, a secondary test method known as the Parallel Thermal Conductance technique was researched and a proposed model of it was designed for use in temperatures up to 300°C. Due to the relatively short test time of the Harman Technique, it was also used to effectively bin incoming groups of TEGs used in the POWER system so that they could be placed strategically in different areas of heat flow based on their measured performance. An increase of 13.2% was observed in the electrical output of the system after the binning had occurred. / Thesis / Master of Applied Science (MASc)

This study attempted to classify the characters in Greene's dramas and among other things, the study tried to show which characters are individuals and which are types.

No description available.