The measurement of humidity is rapidly increasing in importance in physical, chemical and biological processes as industry attempts to improve quality and production rates by better control of relative humidity (RH). A novel optical fibre humidity sensor suitable for use in an optical fibre multi-point distributed sensing system has been developed, thus for the first time allowing multipoint measurements of humidity along an optical fibre which can be distributed within an industrial plant or machine without the need for electrical power supplies. The novel point sensor is based on the principle of using the absorption spectrum of a colorimetric reagent (cobalt chloride) immobilised on the surface of the core of a multimode optical fibre by employing a thin gelatin film. The single point sensor has an insertion loss of less than 0.2 dB. Two-wavelength detection is employed to provide referencing to eliminate common mode intensity variation. The basic design, construction and testing of an experimental sensor in the humidity region 20 to 80% RH and temperature range 25 to 50 °C is described. Resolution and Repeatability can be better than 2% RH with a time constant of 0.5 second. A two-wavelength optical time domain reflectometer (OTDR) has been developed and a four-sensor network has been built. The resolution of measurement on the network can be better than 4% RH, but because of noise in the OTDR the resolution value is dependent on averaging time in the instrument.

Ingeniero Civil Químico / Los vidrios biocompatibles han sido ampliamente utilizados en el área clínica en variados usos. El uso del método sol-gel, permitió una mayor versatilidad en la síntesis de éstos, otorgó una mayor área superficial y permitió incorporar modificadores que entreguen propiedades adicionales, con por ejemplo, propiedades antibacteriales. Se sintetizaron biomateriales con la técnica sol gel libre de metales, SiO2 CaO P2O5 (BG) e incorporando plata, SiO2 CaO P2O5 Ag2O (AgBG) y cobre, SiO2 CaO P2O5 CuO (CuBG). Además se controló el grado de incorporación de los metales, creando materiales con un 10% y 5% molar de metales: AgBG(2) y AgBG(1), respectivamente para plata, y CuBG(2) y CuBG(1), respectivamente para cobre. Los materiales sintetizados presentaron las proporciones elementales deseadas, son principalmente amorfos y poseen una alta área superficial, de alrededor de 260 [m2/g]. El material demostró ser biocompatible in-vitro, ya que luego de ser sumergido en SBF (Simulated Body Fluid) presentó un desarrollo de una capa de hidroxiapatita en su superficie, lo que, según con lo reportado el la literatura, se correlaciona directamente con la biocompatibilidad. La incorporación de metales en la síntesis, otorgó a los biovidrios una capacidad bactericida contra la cepa de E. coli DH5α y una cepa clínica de S. mutans, que no se presenta en la ausencia de éstos (BG). Ésta capacidad, medida mediante la concentración mínima bactericida (CMB), no presentó diferencia entre el grado de incorporación de los respectivos metales y es mayor en el caso de los AgBG, con una CMB para E. coli: ~3[mg/mL] en 24 h y ~0,4[mg/mL] en 48 h y para S. mutans: ~1,3 [mg/mL] en 48 h, con respecto a los CuBG, con una CMB para E. coli: ~125[mg/mL] en 24 h y ~7,5[mg/mL] en 48 h y para S. mutans: ~7,5[mg/mL] en 48 h. Este resultado depende de la bacteria y del tiempo de exposición del material a la misma, donde esta diferencia tiende a disminuir con un mayor tiempo de exposición, Si bien, la plata presentó mejores propiedades antibacteriales que el cobre, este último presentó una tendencia a alcanzar los niveles bactericidas de la plata, además hay que considerar el hecho que el cobre es aproximadamente diez veces más barato y menos tóxico para los seres humanos que la plata.

Doctor of Philosophy / Department of Chemistry / Christopher T. Culbertson / My doctoral dissertation consists of three fundamental studies: 1) synthesis of biocompatible materials that can be used as microfluidic substrates, 2) characterizing these materials with respect to properties important to microfluidic fabrication, biochemical separations and concentration enrichment, and 3) employing these novel devices for real world applications in bioanalytical chemistry. The surface properties of a substrate will dramatically affect the resolution and efficiency that can be obtained for a specific CE separation. Thus, the ability to modify the surface is very useful in tailoring a microfluidic chip to a specific separation mode. The substrates we have synthesized for microfluidic devices include metal oxide modified poly(dimethylsiloxane) (PDMS), poly(ethyleneoxide)-PDMS (PEO-PDMS) coblock polymers, and surfactant coated PDMS. The metal oxide modified PDMS materials we synthesized include silica-PDMS, titania-PDMS, vanadia-PDMS and zirconia-PDMS. The surfaces of these materials were characterized using contact angle, X-ray photoelectron spectroscopy (XPS), Raman, transmission electron microscopy (TEM), scanning electron microscopy (SEM), atomic force microscopy (AFM) and electroosmotic mobility (EOM) measurements. All of the metal oxide modified PDMS surfaces were significantly more hydrophilic than native PDMS, suggesting potential application in separations of biopolymers. In addition to being more hydrophilic the EOF and zeta potential of the channels were stable and quite durable with aging. Well characterized silane chemistry was used to derivitize the surface of the PDMS metal oxide surfaces allowing a number of different functionalities to be placed on the surface. This method has the potential for wide applicability in many different fields, but specifically for the fabrication of microstructures that need specific surface chemistries. We have also made a number of advancements using sol-gel chemistry and laminar flow within microfluidic channels to fabricate nanoporous membranes. Sol-gel patterned membranes are a simple and facile method of incorporating nanoscale diameter channels within a microfluidic manifold. These membranes have been used to perform preconcentration of amino acids, proteins and small particles for further analysis and separation using CE. We are also using these membranes for further study in desilanization and protein recrystallization studies.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-08-01T14:15:51Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE_FINAL.pdf: 9343750 bytes, checksum: d6046e58d75229c6c16cedf05999099d (MD5) / Made available in DSpace on 2017-08-01T14:15:51Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE_FINAL.pdf: 9343750 bytes, checksum: d6046e58d75229c6c16cedf05999099d (MD5) Previous issue date: 2017-01-04 / CNPQ / No presente trabalho foram investigadas as propriedades magnéticas e estruturais do composto Y3(Fe1-xZnx)5O12, (x = 0; 0,01; 0,03; 0,05), obtido pelo método sol gel. Também, foram estudados filmes finos de Y3Fe5O12, preparados pelo método de deposição de soluções químicas (sol gel). Para ambos os estudos, utilizaram-se técnicas de caracterização estrutural, morfológica e magnética. Para a síntese das nanopartículas de Y3(Fe1-xZnx)5O12 foram utilizados materiais à base de nitratos e água destilada como solvente. As temperaturas características da decomposição do material foram analisadas utilizando a técnica termogravimétrica e calorimetria diferencial de varredura. Este estudo mostrou que existem várias etapas na formação do material, relacionadas com as perdas de água e de materiais orgânicos e com a formação da fase cristalina. Três famílias de amostras foram sinterizadas nas temperaturas seguintes: i) 900°C, ii) 1000°C iii) 1100°C. A caracterização estrutural do primeiro grupo (900°C) apresentou uma única fase cristalográfica, correspondente à granada de ítrio e ferro. O aumento observado no parâmetro de rede foi relacionado com o maior raio iônico do Zn2+ em relação ao do Fe3+. A morfologia dos grãos foi determinada utilizando a técnica de microscopia eletrônica de varredura, mostrando formatos alongados e aumento do tamanho dos aglomerados com o incremento da concentração de Zn2+. O pico referente ao íon de Zn2+ foi observado mediante a técnica de Espectroscopia de energia dispersiva, corroborando sua presença dentro da estrutura cúbica da granada. A espectroscopia Raman revelou um aumento da intensidade na banda principal (271,8 cm-1) com o incremento da dopagem. A análise magnética mostrou um incremento na magnetização de saturação para a amostra dopada em 1%, enquanto uma diminuição foi observada para as maiores concentrações de Zn2+, associada ao enfraquecimento do acoplamento magnético no sítio octaédrico. A análise estrutural da segunda família de amostras (1000°C) indicou a presença de uma nova fase cristalográfica, pertencente à fase ortorrômbica do YIG, representando 2 % do total da amostra; ao mesmo tempo, no terceiro grupo de amostras (1100°C), se observaram reflexões típicas do composto franklinita. Estes resultados, junto ao observado nas curvas de TG-DSC, sugeriram a presença de um composto metaestável. O momento magnético em função do campo aplicado, na família de amostra sinterizada a 1000°C, apresentou uma diminuição na magnetização de saturação com o incremento da concentração de Zn2+. As curvas da magnetização em função da temperatura foram ajustadas a partir da lei de Bloch, obtendo valores similares aos reportados na literatura para o YIG dopado com outros íons. Para a preparação dos filmes de Y3Fe5O12, foi desenvolvida uma metodologia química geral, a qual tem por base o álcool isopropílico, usado como solvente na primeira família de filmes e 2-methoxyethanol como solvente na síntese modificada. A caracterização estrutural dos filmes obtidos com álcool isopropílico mostrou a fase cristalográfica ortorrômbica como majoritária e picos que cristalizam na fase cúbica. Além disso, todos os filmes apresentaram deformações morfológicas provocadas pela interação filme-substrato de silício. A largura de linha por FMR obtida encontra-se entre 75 e 78 Oe. No filme obtido a partir da síntese modificada observou-se a fase cúbica do YIG como predominante, com pequenas reflexões da fase ortorrômbica. A imagem de microscopia eletrônica de varredura mostrou a formação de um filme uniforme, com uma pequena quantidade de poros distribuída uniformemente na superfície. A medida de ressonância ferromagnética com o ajuste mostrou uma largura de linha de 53 Oe. Correspondendo ao valor mais baixo reportado na literatura para filmes finos de YIG sobre substrato de silício e usando métodos químicos. / The magnetic and structural properties of Y3(Fe1-xZnx)5O12, (x = 0; 0,01; 0,03; 0,05) obtained by the sol gel method were investigated. As well, thin films of Y3Fe5O12, prepared using spin-coating of chemical solutions (sol-gel) were characterized. The synthesis of Y3(Fe1-xZnx)5O12 nanoparticles was using precursors based on nitrates and distilled water as the solvent. The decomposition temperatures of dried gel were examined using the Thermogravimetry and Differential Scanning Calorimetry techniques. There are several steps in the decomposition of the dried gel; related to the loss of water and organic materials, as well as the formation of the crystalline phase. Three families of samples were prepared at different temperatures of the thermal treatment: i) 900°C, ii) 1000°C and iii) 1100°C. The structural characterization of the first group (900°C) presented a single crystallographic phase, corresponding to the yttrium iron garnet. The increasing in lattice parameter was associated to the largest ionic radius of Zn2+ ions compared to the Fe3+ ions. The morphology of the grains was determined using scanning electron microscopy, showing elongated shapes and a growing of agglomerates as Zn2+ concentration increases. The characteristic peak of Zn2+ was observed by Dispersive Energy Spectroscopy, increasing the intensity with the dopant concentration, corroborating the presence of the element within the cubic structure of the garnet. Raman spectroscopy revealed an increasing in the main band (271.8 cm-1) and the octahedral sites are more likely for the substitution of Fe3+ by Zn2+. The measurements showed the maximum value for magnetic saturation in the 1% doped sample, while a decreasing was observed for highest concentrations of Zn, associated to the weakening of the magnetic coupling across the octahedral site. The structural analysis of the second group of samples (1000°C heat treatment), showed the yttrium iron garnet and the orthorhombic phase (until 2%). The third group of samples (1100°C heat treatment) showed yttrium iron garnet and the orthorhombic phase (until 4%) and typical reflections of Franklinite (until 4%). The magnetic moment versus the applied field, in the family of samples sintered at 1000°C, showed a decreasing in the saturation magnetization as Zn2+ concentration increases. The results of fittings according to Bloch's law showed magnetic parameters similar in values, compared to those reported in the literature for YIG doped with other ions. The second part of our study aim the preparation of thin films of Y3Fe5O12 using sol gel based in isopropyl alcohol (in the first tentative) and 2-methoxyethanol in the modified synthesis. The structural characterization of samples obtained using isopropyl alcohol, showed the orthorhombic crystallographic phase as majority and peaks of the cubic phase. All samples showed a cracked morphology due to the film-substrate interaction and the FMR linewidth ranges from 75 Oe until 78 Oe. In the film obtained from the modified synthesis (using 2methoxyethanol), we observed the majoritary cubic phase of YIG and small reflections of the orthorhombic phase. The scanning electron microscopy image shows a uniform film with pores evenly distributed on the surface. The ferromagnetic resonance measurement and the fitting by the derivative of the Lorentzian function, showed a linewidth of 53 Oe. It is the lowest value reported in the literature for thin films of YIG on silicon substrate and using chemical methods.

Die vorliegende Arbeit beschreibt die Entwicklung von SiO2-basierten nano- und mikroskalig strukturierten Schichten, welche eine Temperaturstabilität > 500 °C sowie eine Strukturtreue > 90 % aufzeigen. Diese wurden unter Verwendung von hybridpolymeren, partikelmodifizierten Sol-Gel-Vorstufen via UV-basierter Nanoimprintlithographie (UV-NIL) hergestellt. Der Einfluss chemischer und verfahrenstechnischer Syntheseparameter auf die anorganische Netzwerkbildung der flüssigen Vorstufe (hybridpolymerer Binder), die Polymerisation und Verdichtung der hybridpolymeren Sol-Gel-Schichten während der thermischen Härtung sowie deren Strukturierung via UV-NIL wurden im Detail untersucht und die erhaltenen Zusammenhänge mit den resultierenden Materialeigenschaften korreliert. Dabei dienten die Kenntnisse hinsichtlich des Schrumpf- und Verdichtungsverhaltens von planaren Schichten als Basis für die daraus hergestellten, strukturierten Schichten. / The present work describes the development of SiO2-based nano- and microstructured coatings with temperature stability > 500 °C and structure fidelity > 90 %. The coatings were produced via UV-nanoimprintlithography (UV-NIL) by using particle modified, hybrid sol-gel-precursors. The influence of synthesis chemical and process parameters on formation of inorganic network of the hybrid binder, polymerisation and densification of hybrid sol-gel-films during thermal annealing and imprinting of the hybrid sol-gel-films were investigated and correlated with resulting material properties. The results of shrinkage and densification of planar coatings were used to characterize the structured coatings.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第20234号 / 医博第4193号 / 新制||医||1019(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 安達 泰治, 教授 横出 正之, 教授 鈴木 茂彦 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Ziel dieser Arbeit war es, ein Schichtsystem auf Basis des Sol-Gel-Prozesses zu entwickeln, um Lighttrapping in Si-Dünnschichtsolarzellen zu erzeugen. Die Grundlage dieses Schichtsystems bilden SiO2-Partikel, die über den Stöber-Prozess hergestellt werden. Es zeigte sich, dass sich die Rauheit und der Haze der Schichten über die Partikelgröße und Schichtdicke einstellen lassen. Um die mechanische Stabilität der reinen Stöber-Schichten zu verbessern, kamen verschiedene Binder zum Einsatz. Beste Ergebnisse zeigten Binder basierend auf löslichen Vorstufenpulvern, da diese dem Stöber-Sol beigemischt werden konnten und so Binder und Partikel gleichzeitig aufgebracht werden konnten. Auf diese Weise entstehen mechanisch stabile, lichtstreuende Schichten. Zum Einsatz kam zunächst ein TiO2-Binder. Durch eine anschließende Glättung der Stöber-TiO2-Streuschichten mit SiO2 entsteht eine defektfreie, aber dennoch raue Oberfläche. Zusätzlich wird ein beträchtlicher Teil des Lichts in große Winkel gestreut. Es konnte gezeigt werden, dass sich auf den SiO2-geglätteten Stöber-TiO2-Streuschichten ZnO:Al deponieren lässt, wobei die elektrischen Eigenschaften von der Dicke der Glättung abhängen. Auch die elektrischen Eigenschaften der Si-Dünnschichtsolarzellen hängen von der Glättung bzw. der Dicke der Glättung ab. Dies gilt insbesondere für die von der Materialqualität abhängigen Parameter Füllfaktor FF und offen Klemmenspannung VOC. Insgesamt fallen die Parameter jedoch noch gegenüber Referenzzellen auf geätztem Frontkontakt zurück. Vor allem aber wurde die hohe Zellreflexion aufgrund der Glas-TiO2-Grenzfläche als primäres Problem identifiziert. Dennoch konnte bei einer Glättungsdicke von 200 nm sehr gutes Lighttrapping beobachtet werden. Verantwortlich hierfür ist sehr wahrscheinlich die Großwinkelstreuung der Stöber-TiO2-Streuschichten. Um die Zellreflexion zu verringern, wurde der Brechungsindex des Binders und der Glättungsschichten an den Stack aus Substrat, Streuschicht und ZnO:Al-Schicht angepasst. Idee war es, durch Einbringen eines Al2O3-Vorstufenpulvers eine niedrigbrechende Komponente bereitzustellen, um durch Mischung von Al2O3- und TiO2-Vorstufenpulver freie Hand über den Brechungsindex des Binders und der Glättung zu erhalten. Da sich das Volumenverhältnis von SiO2-Partikeln zu Binder bei verschiedenen Al2O3-TiO2-Verhältnissen nur schwer bestimmen lässt, wurde lediglich ein reiner Al2O3-Binder in den Streuschichten eingesetzt. Die Einstellung des Brechungsindex beschränkte sich allein auf die Glättungsschichten. Um Stöber-Al2O3-Streuschichten mit hoher Rauigkeit und geringen Defekten zu erzielen, muss das Binder-zu-Partikel-Verhältnis angepasst werden. Beste Ergebnisse ergaben sich bei einem Al2O3-Gehalt von 2% im Sol. Aufgrund der hohen Rauigkeit besitzen die Streuschichten einen hohen Haze und wegen des geringen Brechungsunterschied zwischen Glas und Binder eine hohe Transmission. Die Glättung der Streuschichten im Al2O3-TiO2-System ist nur mit Hilfe einer zusätzlichen SiO2-Glättungsschicht und einer reduzierten Dicke auf 50 nm möglich. Auf den reinen defektreichen Streuschichten tendieren die Al2O3-TiO2-Schichten selbst zu Rissbildung. Zur Untersuchung der ZnO:Al-Deposition wurde eine Glättungsdicke von 200 nm gewählt. Die erwies sich als zu gering. Die aufgebrachten ZnO:Al-Schichten wiesen größere Poren und kleinere Oberflächendefekte auf. Die Anpassung des Brechungsindex der Glättungsschichten an die ZnO:Al-Schicht erwies sich nicht als vorteilhaft. Die reine Al2O3-Glättung zeigt auch nach der ZnO:Al-Deposition die höchste Transmission. Die Winkelverteilung des Streulichts der Stöber-Al2O3-Streuschichten ist gegenüber den Stöber-TiO2-Streuschichten zu kleineren Winkeln verschoben. Dennoch wird ein größerer Anteil des Lichts in große Winkel gestreut, als es bei der geätzten ZnO:Al-Referenz der Fall ist. Trotz der Defekte in den ZnO:Al-Schichten konnten auf den Stöber-Al2O3-Streuschichten funktionierende Tandemzellen hergestellt werden. Der Füllfaktor und die offene Klemmenspannung fallen nur geringfügig hinter die der Referenzzelle zurück. In der Kurzschlussstromdichte machen sich die verringerte Zellreflexion und das sehr gute Lighttrapping bemerkbar, so dass das Niveau der Referenz erreicht werden konnte. Zu beachten ist allerdings, dass gerade im langwelligen Lighttrapping-Spektralbereich die gleiche EQE erreicht wurde, trotz immer noch leicht erhöhter Zellreflexion. Die letzte Versuchsreihe konnte zeigen, dass die entwickelten Schichten sich sehr gut zur Erzeugung von Lighttrapping in Si-Dünnschichtsolarzellen eignen. / The aim of this thesis was to develop a coating system based on the sol-gel process to generate light trapping in Si thin film solar cells. The foundation of this coating system are SiO2 particles which are produced by the Stöber process. The roughness and the haze of the layers can be adjusted by means of the particle size and layer thickness. To improve the mechanical stability of the pure Stöber layers different binders were used. The best results were found in binders based on soluble precursor powders, as they could be mixed with the Stöber sol so that binders and particles could be applied simultaneously. This results in mechanically stable, light-scattering layers. Initially, a TiO2 binder was used. A subsequent smoothing of the Stöber-TiO2 scattering layers with SiO2 results in a defect-free but nevertheless rough surface. In addition, a considerable part of the light is scattered in large angles. It was shown that ZnO: Al can be deposited on the SiO2 -smoothed Stöber-TiO2 scattering layers, the electrical properties depending on the thickness of the smoothing. The electrical properties of the Si thin-film solar cells also depend on the smoothing or the thickness of the smoothing. This is especially true for the material quality dependent parameters fillfactor FF and open circuit voltage Voc. Overall, however, the parameters still fall short of reference cells on etched front contact. Most importantly, the high cell reflectance was identified as the primary problem due to the glass-TiO2 interface. Nevertheless, very good light trapping could be observed with a smoothing thickness of 200 nm. This is most likely due to the large-angle scattering of the Stöber-TiO2 scattering layers. In order to reduce the cell reflection, attempts have been made to adapt the refractive index of the binder and the smoothing layers to the stack of substrate, scattering layer and ZnO:Al. The idea was to provide a low refractive component by adding an Al2O3 precursor powder in order to obtain full control on the refractive index of the binder and the smoothing by mixing Al2O3 and TiO2 precursor powders. Since the volume ratio of SiO2 particles to binders is difficult to determine at different Al2O3-TiO2 ratios , only a pure Al2O3 binder was used in the scattering layers. The adjustment of the refractive index was limited solely to the smoothing layers. To achieve Stöber-Al2O3 scattering layers with high roughness and low defects, the binder-to-particle ratio must be adjusted. The best results were obtained with an Al2O3 content of 2% in the sol. Due to the high roughness, the scattering layers have a high Haze and a high transmission because of the small difference in refraction index between glass and binder. The smoothing of the scattering layers in the Al2O3-TiO2 system is only possible with the aid of an additional SiO2 smoothing layer and a reduced thickness to 50 nm . On the pure defect-rich scatttering layers, the Al2O3 -TiO2 layers themselves tend to crack. To investigate the ZnO:Al deposition, a smoothing thickness of 200 nm was chosen. That turned out to be too low . The applied ZnO:Al layers had larger pores and smaller surface defects. The adjustment of the refractive index of the smoothing layers to the ZnO:Al layer did not prove to be advantageous. The pure Al2O3 smoothing shows the highest transmission even after the ZnO:Al deposition. The angular distribution of the scattered light of the Stöber-Al2O3 scattering layers is shifted towards smaller angles than the Stöber-TiO2 scattering layers. Nevertheless, a larger fraction of the light is scattered into large angles than is the case with the etched ZnO:Al reference. Despite the defects in the ZnO:Al layers , functional tandem cells could be prepared on the Stöber- Al2O3 scattering layers. The fill factor and the open circuit voltage fall only slightly behind those of the reference cell. The short-circuit current density, the reduced cell reflection and the very good light trapping are noticeable, so that the level of the reference could be reached. It should be noted, however, that the same EQE was achieved in the long-wavelength light trapping spectral range, despite the still slightly increased cell reflection. The last series of experiments showed that the developed layers are very well suited for the generation of light trapping in Si thin-film solar cells.

The use of sol-gel immobilization in the fabrication of microarrays is a relatively new approach that has shown potential to become a leading methodology in this field. However, there are a limited number of assay systems that have been reported using this method. Furthermore, methods to produce high-density sol-gel-derived microarrays have not been reported. Herein, two novel assays utilizing sol-gel-derived microarrays are presented. In the first case, the solid phase of sol-gel-derived microarrays was employed as a detection platform for monitoring the activity of glycogen synthase kinase 3-β (GSK3β) in solution using a phosphospecific stain. Using this assay format, the ability to detect hyperphosphorylated product over the pre-phosphorylated substrate was demonstrated and a z' value of 0.49 was obtained, indicating amenability to small molecule screening. Secondly, a fluorogenic assay for acetylcholinesterase (AChE) was development that is compatibility with sol-gel derived microarrays and standard imaging instrumentation. A thiol-reactive fluorogenic dye, typically used for detection of thiolated oligonucleotides, was successfully used to monitor AChE activity both in solution and in silica. Further, a functional sol-gel-derived AChE microarray was fabricated and activity on array was detected. We have also reported on the optimization of materials for the fabrication of high-density kinase microarrays using sol-gel immobilization. By employing a directed criteria-based screen, optimal materials were quickly and efficiently identified. Two materials, 1.5SS/1PV A/Glycerol and 0.25DGS, were identified as the optimal materials for fabrication of sol-gel-derived functional microarrays. / Thesis / Master of Science (MSc)

No description available.

The functionality of a novel 3-dimensional betavoltaic battery design will be investigated to improve conversion efficiency over existing planar devices. A beta-emitting isotope of nickel, Ni-63, is embedded in the volume of empty space between self-assisted p-i-n junction gallium phosphide nanowires to improve the beta capture efficiency. Parameters such as nanowire pitch, diameter, and height will influence the efficiency and were investigated thoroughly. Material selection was performed based on the following considerations. Gallium phosphide is chosen to achieve a high open circuit voltage under beta exposure. Ni-63 has an optimal beta energy spectrum for a nanowire device and a half-life of 101 years for long term application. The majority of the work focused on the development of the fabrication process, particularly the radioactive source deposition. The method used for embedding the source was a citrate-based sol-gel which was spun onto the sample. This method was modified for this nanowire application and specific challenges to the process are outlined. Furthermore, the obstacles of working with radioactive materials will be discussed. The first nanowire-based betavoltaic device is reported to produce beta-generated current and achieved a beta conversion efficiency of 0.03%. Investigation of the junction was performed to provide future improvements to the efficiency. Additionally, simulated IV curves for a non-active sample exhibited a possible conversion efficiency of 1.92%. / Thesis / Master of Applied Science (MASc)