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[pt] No presente trabalho, a cromatografia eletrocinética capilar micelar (MECC) e a fosforimetria em temperatura ambiente em substrato sólido (SSRTP) foram utilizadas como técnicas analíticas para a determinação de duas estrobilurinas (picoxistrobina e piraclostrobina) e de uma fluoroquinolona (enrofloxacina), respectivamente. As condições ótimas de analise por MECC foram determinadas a partir de um estudo univariado dos seguintes parâmetros experimentais e instrumentais: pH do eletrólito de corrida, concentração do tampão, concentração de surfactante (dodecil-sulfato de sódio - SDS), tipo e quantidade de modificador orgânico, temperatura de trabalho e diferença de potencial aplicada. Depois de definidas as condições ótimas (tampão borato 40 mmol L-1, pH igual a 8,5; SDS 30 mmol L-1; acetonitrila 15 por cento em volume, 25 gruas Celsius e 25 kV) foi realizado um estudo para diminuir o limite de detecção (LD) e o limite de quantificação (LQ) do método. Para tal, foi usado o modo de pré-concentração no capilar denominado modo de empilhamento normal (NSM). Nessa abordagem, as soluções de padrões e amostras foram dissolvidas em uma solução de maior impedância (água: borato 40 mmol L-1 pH igual a 8,5 50:50 por cento v/v). Uma cela de caminho óptico alongado também foi utilizada para a tentativa de aumentar a sensibilidade do método. As curvas analíticas foram construídas com o uso de padrão interno (azoxistrobina) e apresentaram comportamento linear e homocedástico com valores de R2 próximos a 0,999. Com o modo NSM, os valores de LD (xb mais 3sb) e de LQ (xb mais 10sb) para a picoxistrobina e para a piraclostrobina ficaram na ordem de 10-7 mol L-1. A precisão do método (repetitividade e reprodutibilidade interna) apresentaram valores entre 5 e 8 por cento para tempo de migração e área dos picos. O método foi aplicado na análise de urina e água de riacho, ambas fortificadas com as estrobilurinas. As amostras de urina foram previamente passadas em coluna de extração em fase sólida (C-18). As recuperações obtidas para a piraclostrobina foram 75 mais ou menos 4 por cento para as amostras de urina e 94 ou menos 10 por cento para as amostras de água de riacho. Para a picoxistrobina os valores de recuperação foram de 109 mais ou menos 9 por cento e 102 mais ou menos 9 por cento para as amostras de urina e água do riacho respectivamente. As características fosforescentes da enrofloxacina foram estudadas de modo univariado em função de vários parâmetros experimentais tais como o tipo e quantidade de sal de átomo pesado indutor de fosforescência, presença de surfactante modificador de superfície de celulose, influência de concentração hidrogeniônica na solução do analito e estudo do tempo de exposição ao UV para a formação de fotoproduto de sinal mais estável. As melhores condições para o método fosforescente para enrofloxacina foram obtidas em solução básica (solução acetona: NaOH 0,05 mol L-1 50:50 por cento v/v) irradiada com UV por 30 min e substrato contendo 80 Vg de TlNO3. O método foi aplicado em formulações farmacêuticas contendo enrofloxacina e que são utilizadas na medicina veterinária (solução e comprimidos). Um método com a técnica de cromatografia líquida de alta eficiência (HPLC) adaptado da literatura foi utilizado para análise das amostras de enrofloxacina, sendo os resultados comparáveis àqueles obtidos por SSRTP. A curva analítica apresentou resposta linear e homoscedástica na faixa de trabalho escolhida com R2 maior que 0,99. Os valores de LD (xb mais 3sb) e de LQ (xb mais 10sb) foram respectivamente 2,1 and 4,8 ng respectivamente. A precisão (repetitividade e reprodutibilidade interna com troca de analista) do método apresentaram valores entre 2 e 19 por cento. A incerteza de medição do sinal fosforescente foi calculada usando o método sistemático indicado no ISO GUM e valores entre 18 e 26 por cento foram alcançados, com valores de repetitividade com troca de substrato a fonte mais importante de incerteza. No procedimento de validação, os valores de concentração de enrofloxacina encontrados nas amostras de medicamento analisadas por SSRTP e por HPLC foram estatisticamente semelhantes (valor de texperimental iguais a 0,48 e 1,04 sendo menor que o valor de tcrítico igual a 2,23). / [en] In the present work, micellar electrokinectic capillary chromatography (MECC) and solid surface room-temperature phosphorimetry (SSRTP) were used as analytical techniques for the determination of two strobilurins (picoxystrobin and pyraclostrobin) and of one fluoroquinolones (enrofloxacin), respectively. The experimental conditions for MECC have been optimized using an univariate approach for the following experimental and instrumental parameters: pH of the working electrolyte, concentration of the buffer, concentration of surfactant (sodium dodecyl-sulphate - SDS), type and amount of organic modifier, working temperature and applied potential. After defined the best conditions (borate buffer 40 mmol L(-1) pH=8.5; 30 SDS mmol L(-1); acetonitrile 15% in volume, 25 ºC and 25 kV), a study was carried through to improve the limit of detention (LD) and the limit of quantification (LQ) of the method. In order to do that, an on-line analyte pre-concentration called normal stacking mode (NSM) was used. In such approach, the standards and samples have been dissolved in a solution of higher impedance (water: borate 40 mmol L(-1) pH=8.5 50:50% v/v). A high sensitivity detection cell also was used to attempt the increasing of the sensitivity of the method. The analytical curves have been constructed with the use of an internal standard (azoxystrobin) and a linear response and homocedastic behavior were observed with R2 values of at least 0.999. The NSM mode allowed the values of LD (x(b) + 3(sb)) and of LQ (x(b) + 10(sb)) in the order of 10(-7) mol L(-1) for picoxystrobina and pyraclostrobina. The precision of the method (repeatability and intermediate precision) was characterized by values between 5 and 8%. The method was applied in the analysis urine and stream water, both type of samples fortified with the strobilurins. The urine sample was previously passed through a solid phase extraction column (C-18). The recoveries achieved for pyraclostrobina were 75  +- 4% for urine and 94  +- 10% for stream water samples. For picoxystrobin, the recovery values were 109  +- 9% and 102  +- 9% respectively for urine and stream water samples. The phosphorimetric characteristics of enrofloxacin have been studied in an unvaried way for experimental parameters such as the type and quantity of phosphorescence inducer (heavy atom salt), surfactant used as cellulose surface modifier, influence of the hidrogenionic concentration in the analyte solution and study of the UV exposition time for the formation of a more signal stable photoproduct. The best conditions for the phosphorimetric method for enrofloxacin were the use of basic solution (solution acetone: NaOH 0.05 mol L-1 50:50% v/v) irradiated with UV for 30 min and cellulose substrates containing 80 Vg of TlNO3. The method was applied in pharmaceutical formulations containing enrofloxacin employed in veterinary medicine (solution and pills). A method based on high efficiency liquid chromatography (HPLC), adapted from literature, was used as a reference method and the the results obtained for enrofloxacin was comparable to the ones achieved by SSRTP. The analytical curve presented linear and homocedastic behavior with R2 values higher than 0.99. The LD (x(b) + 3(sb)) and the LQ (x(b) + 10(sb)) values were 2.1 and 4.8 ng respectively. The precision (repeatability and intermediate precision with change of analyst) of the method presented values between 2 and 19%. The uncertainty of the phosphorescence measurement was calculated using the systematic method indicated in the ISO GUM. Values between 18 and 26% had been achieved, with the repeatability with substrate change the most important source uncertainty. In the validation procedure, enrofloxacin concentration values found in the medicine samples analyzed by SSRTP and HPLC were statistically similar ( t(experimental) value of 0.48 and 1.04 smaller than the t(critic) value of 2.23).

The client is an organization founded and is operational in Sweden, Stockholm. The company focuses on manufacturing of clean tech solutions with its self-developed technology. Their technology generate power from renewable sources. The technology is applied to a substrate which is manufactured inside the factory, today's handling of the substrate must be made more effective. The purpose of the work is to analyze and optimize the handling of substrate in the factory. This includes from substrate manufacturing to storage to the next process in the chain.  The approach to the work began with a background study, preparation of a schedule, development of concepts and concept evaluation. To structure the work, the decision was made to follow the methods developed in the book Six Sigma’s.  The background study gathered information and knowledge about the subject to give a more profound understanding. Market studies were also conducted to find suitable solutions as well as components and products.  Several concepts were developed using brainstorming. The concepts were evaluated intuitively and using Pugh's matrix. The most suitable concept was further developed and dimensioned based on the conditions. Computer models were manufactured for the development and illustration of concepts.  The project resulted in the way the company transfer rolls today is the most optimal with the conditions that exist. The focus was therefore shifted to the development of a paternoster plant for storing rolls. The storage system that was developed holds up to 10 rolls at a time with a weight of 450 kg each. The construction has a maximum height of 3,17 meters, width of 3 meters and a depth of 1,6 meters. The concept will increase the efficiency of the workers by making it easier to sort rolls and reduce the workload.  There are several possibilities for improvement for optimizing the substrate handling in the factory and these are discussed in the last chapter. / Uppdragsgivaren är ett företag grundat och operativa i Sverige, Stockholm. Företaget inriktar sig mot tillverknings av lösningar för grön energi med sin egenutvecklade teknik. Tekniken appliceras på ett substrat som tillverkas i fabriken, dagens hantering av substratet måste effektiviseras och automatiseras. Syftet med arbetet är att analysera och optimera hanteringen av substrat i fabriken. Detta omfattar förflyttningen från substrattillverkning till lagring, till och med nästa process grupp i kedjan.  Tillvägagångssättet för arbetet började med en bakgrundsstudie, upprättning av tidsschema, utveckling av koncept och konceptevaluering. För att strukturera arbetet togs beslutet att följa metoderna framtagna i boken Six Sigmas.  I bakgrundsstudien samlades information och kunskap kring ämnet för att ge en djupare förståelse. Marknadsstudier genomfördes även för att finna lämpliga lösningar samt komponenter och produkter.  Ett flertal koncept utvecklades med hjälp av brainstorming. Koncepten utvärderades med hjälp av Pughs matris. Det mest lämpliga konceptet vidareutvecklades och dimensionerades utifrån förutsättningarna. Datormodeller tillverkades för utveckling och illustrering av koncept.  Projektet resulterade i att sättet förtaget förflyttar rullar idag är det optimalaste med dom förutsättningarna som existerar. Fokuset förflyttades därför till utveckling av ett paternosterverk för lagring av rullar. Lagrings systemet som utvecklades håller upp till 10 rullar samtidigt med en vikt på 450 kg styck. Konstruktionen har en maximal höjd på 3 meter, bredd på 3 meter och ett djup på 1,6 meter. Konceptet kommer öka effektiviteten för arbetarna genom att enklare sortera rullar och minska arbetsbelastningen.  Flera förbättringsmöjligheter finns för optimering av substrathanteringen i fabriken och dessa tas upp i sista kapitlet.

Nanostructures have potential for use in state-of-the-art applications such as sensing, imaging, therapeutics, drug delivery, and electronics. The ability to fabricate and engineer these nanoscale materials is essential for the continued development of such devices. Because the morphological features of nanomaterials play a key role in determining chemical and physical properties, there is great interest in developing and improving methods capable of controlling their size, shape, and composition. While noble nanoparticles have opened the door to promising applications in fields such as imaging, cancer targeting, photothermal treatment, drug delivery, catalysis and sensing, the synthetic processes required to form these nanoparticles on surfaces are not well-developed. Herein is a detailed account on efforts for adapting established solution-based seed-mediated synthetic protocols to structure in a substrate-based platform. These syntheses start by (i) defining heteroepitaxially oriented nanostructured seeds at site-specific locations using lithographic or directed-assembly techniques, and then (ii) transforming the seeds using either a solution or vapor phase processing route to activate kinetically- or thermodynamically-driven growth modes, to arrive at nanocrystals with complex and useful geometries. The first series of investigations highlight synthesis-routes based on heterogeneous nucleation, where templates serve as nucleation sites for metal atoms arriving in the vapor phase. In the first research direction, the vapor-phase heterogeneous nucleation of Ag on Au was carried out at high temperatures, where the Ag vapor was sourced from a sublimating foil onto adjacent Au templates. This process transformed both the composition and morphology of the initial Au Wulff-shaped nanocrystals to a homogeneous AuAg nanoprism. In the second case, the vapor-phase heterogeneous nucleation of Cu atoms on Au nanocrystal templates was investigated by placing a Cu foil next to Au templates and heating, which caused the Cu atoms from the foil to sublimate from the foil and heterogeneously nucleation on the surface of the immobilized Au seeds. This process caused the composition and morphology of the Au Wulff-shape to transform into a homogeneous AuCu nanotriangle. Lastly, we characterized the morphological features and composition, optical properties, and also the catalytic and photocatalytic performance toward hydrogenation of 4-nitrophenolate. The second series of investigations highlight synthetic routes utilizing competencies of substrate-based techniques with colloidal chemistry. We have demonstrated two substrate-based syntheses yielding bimetallic nanostructures where shape control was achieved through (i) facet-selective capping agents and (ii) additive and subtractive process. In the first case a citrate-based cubic structure has been synthesized in the presence or absence of ascorbic acid and the role of each has been considered in shape control. Reactions were carried out in which Ag+ ions were reduced onto substrate-immobilized Ag, Au, Pd, and Pt seeds. It was discovered that for syntheses lacking ascorbic acid, citrate acts as both the capping and the reducing agent, resulting in a robust nanocube growth mode; however, when ascorbic acid was included in these syntheses, then the growth mode reverted to one that advances the octahedral geometry. The conclusion of these results was that citrate, or one of its oxidation products, selectively caps (100) facets, but where this capability was compromised by ascorbic acid. In the second case, galvanic replacement reactions have been carried out on immobilized cubic and Wulff structures to create the substrate-based nanoshells and nanocages, where the prepositioned templates were chemically transformed into hollow structures. In this novel research, Wulff-shaped templates of Au, Pt, or Pd, formed through the dewetting of ultrathin films, were first transformed into core−shell structures through the reduction of Ag+ ions onto their surface and then further transformed through the galvanic replacement of Ag with Au. Detailed studies were provided highlighting discoveries related to (i) alloying, (ii) dealloying, (iii) hollowing, (iv) crystal structure and (vi) the localized surface plasmon resonance (LSPR). Overall, a series of synthetic strategies based on physical and chemical vapor deposition were devised and validated to achieve novel substrate- based nanomaterials with different shapes and compositions for a variety of applications such as sensing, plasmonics, catalysis, and photocatalysis. The novel research in this dissertation also takes advantage of competencies of substrate-based techniques with colloidal chemistry and, brings this rich and exciting chemistry and its associated functionalities to the substrate surface. / Mechanical Engineering

This dissertation focuses on the development of low-temperature co-fired ceramics (LTCC) technology for power converter magnetics integration. Because magnetic samples must be fabricated with thick conductors for power applications, the conventional LTCC process is modified by cutting trenches in the LTCC tapes where conductive paste is filled to produce thick conductors to adapt to this requirement. Characterization of the ceramic magnetic material is performed, and an empirical model based on the Steinmetz equation is developed to help in the estimation of losses at frequencies between 1 MHz to 4 MHz, operating temperature between 25 °C and 70 °C, DC pre-magnetization from 0 A/m to 1780 A/m, and AC magnetic flux densities between 5 mT to 50 mT. Temperature and DC pre-magnetization dependence on Steinmetz exponents are included in the model to describe the loss behavior. In the development of the LTCC chip inductor, various geometries are evaluated. Rectangular-shaped conductor geometry is selected due to its potential to obtain a much smaller footprint, as well as the likelihood of having lower losses than almond-shaped conductors with the same cross-sectional area, which are typically a result of screen printing. The selected geometry has varying inductance with varying current, which helps improve converter efficiency at light load. The efficiency at a light-load current of 0.5 A can be improved by 30 %. Parametric variation of inductor geometry is performed to observe its effect on inductance with DC current as well as on converter efficiency. An empirical model is developed to describe the change in inductance with DC current from 0 A to 16 A for LTCC planar inductors fabricated using low-permeability tape with conductor widths between 1 mm to 4 mm, conductor thickness 180 μm to 550 μm, and core thickness 170 μm to 520 μm. An inductor design flow diagram is formulated to help in the design of these inductors. Configuring the inductor as the substrate carrying the semiconductor and the other electronic components is a next step to freeing the surface area of the bulky component and improving the power density. A conductive shield is introduced between the circuitry and the magnetic substrate to avoid adversely affecting circuit operation by having a magnetic substrate in close proximity to the circuitry. The shield helps reduce parasitic inductances when placed in close proximity to the circuitry. A shield thickness in the range of 50 μm to 100 μm is found to be a good compromise between power loss and parasitic inductance reduction. The shield is effective when its conductivity is above 10⁷ S/m. When a shield is introduced between the inductor substrate and the circuitry, the sample exhibits a lower voltage overshoot (47 % lower) and an overall higher efficiency (7 % higher at 16 A), than an inductor without a shield. A shielded active circuitry placed on top of an inductive substrate performs similarly to a shielded active circuitry placed side-by-side with the inductor. Using a floating shield for the active circuitry yields a slightly better performance than using a grounded shield. / Ph. D.

Low substrate regulated microaerophilic behavior (LSRMB), as measured by changes in microaerophilic band formation in semi-solid medium, was observed in several aerobic bacteria isolated from subsurface soils, Antarctic dry valley soils, an eutrophic pond, a mesophilic pond, an oligotrophic lake and activated sludge. Similar behavior was also exhibited by five Pseudomonas and two Bacillus type strains from culture collection. Isolates identified with LSRMB formed a typical band of growth below the surface of low substrate (10 mg/l of peptone, tryptone, yeast extract and glucose) semi-solid medium. Surface growth was obtained when the substrate concentration was increased (1000 mg/l of each of the above mentioned substrates). LSRMB was observed in phylogenetically disparate groups, with all the Pseudomonas and two Bacillus species testing positive for the trait. One of the Gram-negative isolates, strain VT10, was identified by phylogenetic analysis based on its 16S rDNA sequence. High 16S rDNA sequence similarity (99%) was observed with the recently discovered Pseudomonas jessenii (CIP 105274T) type strain. Strain VT10 was used as a model to examine this LSRMB, and show the relationship between oxygen stress and low-substrate growth media. The concentration of 17:0 cyclopropane fatty acid, a common stress indicator, increased 5-fold, and four additional proteins were produced when P. jessenii strain VT10 was grown at low-substrate levels and when the dissolved oxygen concentration was increased from 26 microM to 241 microM. The stress responses by P. jessenii could be due its LSRMB. This study shows that low-substrate regulated microaerophilic behavior helps some microorganisms to track the oxygen minima in their habitat and thus effectively move to an environment, which allows them to thrive. In addition to the above mentioned taxis in response to oxygen concentration, organisms may use chemotaxis to a chemical compound. Quantification of chemotaxis can be extremely difficult. To quantify chemotaxis in an easier fashion, a simplified capillary chemotaxis assay, utilizing a hypodermic needle, syringe and disposable pipette tip was developed. The method was applied to two strains of subsurface microaerophilic bacteria. Strain VT10 was chemotactically attracted toward dextrose, glycerol, and phenol, which could be used as sole carbon sources, and toward maltose, which could not be used. The deep subsurface isolate MR100 (phylogenetically related to P. mendocina) showed no tactic response to these compounds although it could use dextrose, maltose, and glycerol as carbon sources. The chemotaxis results obtained by the new method were verified by using the swarm plate assay technique. The simplified technique may be useful for routine chemotactic testing. / Ph. D.