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As working time increases for most people, dining out and staying up late is inevitable, resulting in bad health conditions. The concentrations of calcium and sodium ion in human blood not only respond directly to health conditions, but can also obtain symptoms of different diseases by observing it. This shows that the concentrations of calcium and sodium ion in human blood are an important index of health. In order to manufacture disposable ion sensor and make it easy to measure, this study uses extended gate field effect transistor (EGFET) with an ion selective membrane(ISM) on top of the gate sensitive layer to replace traditional ion sensitive field effect transistor (ISFET). The ISM adsorbs the appointed ion by means of ion selective medicament which is covered by a macromolecule. The main processing steps of the extended gate field effect transistor developed in this study involve at least four photolithographic and two thin-film deposition processes. The influence of the channel¡¦s width to length ratio, the design of channel, the area of the gate sensitive layer, the energy and dose of ion implantation used for the transistor and ion sensor were investigated. Based on the measurement results of the ion sensor, a sensitivity of 40mV/decade with linearity of 98.589 % is measured for calcium ion concentration in human blood ranging from 5 ¡Ñ 10-3 mol/L to 5 ¡Ñ 10-4 mol/L. On the other hand, a sensitivity of 56 mV/decade with linearity of 98.589 % is measured for sodium ion concentration in human blood ranging from 1 mol/L to 10-1 mol/L.

This study examines the effect of motivation on political selective exposure and selective perception using an online experiment. Studies have found that though people have a preference for like-minded political information over counter-attitudinal information, they do not avoid counter-attitudinal political information altogether (Garrett, 2009; Garrett, Carnahan, & Lynch, 2011; Stroud, 2008). This study examines under what conditions people are likely to expose themselves to more like-minded information than counter-attitudinal information and under what conditions people are likely to seek out more counter-attitudinal information than like-minded information. Based on the theory of motivated reasoning and Hart et al. (2009)'s model, I proposed a model that explained selective exposure and selective perception based on motivation. Defense motivation, the motivation to hold attitude-consistent cognitions with one's original attitudes, beliefs, or behaviors, was predicted to increase selective exposure and selective perception. Accuracy motivation, the motivation to arrive at the correct conclusion, was predicted to reduce selective exposure and selective perception. Finally, information utility motivation, the motivation to choose information that has the highest utility, was predicted to reduce selective exposure when counter-attitudinal information was equally useful as attitude-consistent information, but increase selective exposure when attitude-consistent information was more useful than counter-attitudinal information. In both cases, it was predicted that the selective perception pattern would not be changed. The study also tested the additive effect of the three motivations and examined which motivation can override other motivations in determining selective exposure and selective perception. Results showed that accuracy motivation was effective in reducing selective exposure for both strong partisans and those who were not strong partisans. Accuracy motivation can override defense motivation in affecting selective exposure. Information utility alone, defense motivation alone, and the combination of the three motivations produced mixed results. Accuracy motivation was effective in reducing selective perception for those who were not strong partisans. The link between selective exposure and selective perception was not found.

Traditionally, the condition of hydroponic nutrient solutions used in controlled environment or greenhouse plant production is obtained by monitoring solution pH and electrical conductivity. These parameters provide greenhouse operators with an overall sense of the solution quality, but do not provide information on individual components of the fertilizer solution. Considering that plant nutrient uptake requirements vary with crop, growth phase and environment, real-time ion-selective measurements represent a significant technological advance in the management of recirculating nutrient solutions. The capacity for the monitoring and control of individual ions in the nutrient solution is the last remaining environment variable for which reliable feedback control does not exist in controlled environment plant production. This technology development study focussed on optical ion-selective sensors, termed ‘optrodes’, for potassium and calcium sensing within nutrient solution. Bulk optrode absorption-based sensors, tailored explicitly for nutrient ion activities within typical hydroponic solutions were theoretically modelled, fabricated and experimentally tested. Experimental data on sensor response time, measuring range, selectivity, repeatability, lifetime and influence of temperature were compiled. These ion-selective bulk optrode membranes were integrated into a custom instrument combining a light source, mini-spectrometer, optical fibres and other associated components. Monitoring and control software was written that collected and converted optical measurements into estimated nutrient ion activities for use in managing nutrient solution quality. Implemented spectral averaging, normalization and ratiometric computations and techniques resulted in sensors that offered the advantage of auto-calibration. The sensors met selectivity requirements in half strength Hoagland nutrient solution and provided repeatable measurements in solutions of different ion activity levels. Potassium and calcium selective membranes demonstrated lifetimes of 30 to 50 hours when constantly immersed in nutrient solution. Strategies for their operational implementation in plant growth systems based upon experimental testing are proposed as are suggestions for future study. The low mass, low volume, low cost and robust nature of these optrodes offer a promising technology for future space-based plant production systems and give them excellent terrestrial technology transfer potential.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal

Las especies de metal con diferentes tamaños (átomos individuales, nanocristales y nanopartículas) muestran un comportamiento catalítico diferente para diversas reacciones catalíticas heterogéneas. Se ha demostrado en la bibliografía que muchos factores que incluyen el tamaño de partícula, la forma, la composición química, la interacción metal-soporte, la interacción metal-reactivo / disolvente, pueden tener influencias significativas sobre las propiedades catalíticas de los catalizadores metálicos. Los desarrollos recientes de metodologías de síntesis bien controladas y herramientas de caracterización avanzada permiten correlacionar las relaciones a nivel molecular. En esta tesis, he llevado a cabo estudios sobre catalizadores metálicos desde átomos individuales hasta nanoclusters y nanopartículas. Al desarrollar nuevas metodologías de síntesis, el tamaño de las especies metálicas puede modularse y usarse como catalizadores modelo para estudiar el efecto del tamaño sobre el comportamiento catalítico de los catalizadores metálicos para la oxidación del CO, la hidrogenación selectiva, la oxidación selectiva y la fotocatálisis. Se ha encontrado que, los átomos metálicos dispersados por separado y los grupos subnanométricos de metal pueden aglomerarse en nanoclusters o nanopartículas más grandes en condiciones de reacción. Para mejorar la estabilidad de los catalizadores subnanométricos de metal, he desarrollado una nueva estrategia para la generación de átomos individuales y clusters en zeolitas. Esas especies subnanométricas de metales son estables en tratamientos de oxidación-reducción a 550 oC. Siguiendo esta nueva metodología de síntesis, este nuevo tipo de materiales puede servir como catalizador modelo para estudiar la evolución de especies subnanométricas de metales en condiciones de reacción. La transformación estructural de las especies subnanométricas de Pt ha sido estudiada mediante microscopía electrónica de transmisión in situ. Se ha demostrado que el tamaño de las especies de Pt está fuertemente relacionado con las condiciones de reacción, que proporcionan importantes conocimientos para comprender el comportamiento de los catalizadores de metales subnanométricos en condiciones de reacción. En la otra línea de investigación para catalizadores de metales no nobles, he desarrollado varias estrategias generales para obtener catalizadores de metales no nobles, ya sea soportados sobre óxidos metálicos o protegidos por capas delgadas de carbono. Estos materiales muestran un rendimiento excelente para varias reacciones importantes, como la hidrogenación quimioselectiva de nitroarenos, incluso cuando se comparan con los catalizadores de metales nobles convencionales. En algunos casos, los catalizadores de metales no nobles pueden incluso alcanzar selectividades para productos inviables que no ha sido posible conseguir en catalizadores de metales nobles convencionales, que es causado por la diferente ruta de reacción en catalizadores de metales no nobles. Sin embargo, la espectroscopía fotoelectrónica de rayos X a presión ambiente ha revelado que la irradiación de la luz puede modular la selectividad a los alcoholes y los hidrocarburos C2 +, lo que abre una nueva posibilidad para ajustar el comportamiento catalítico de los catalizadores metálicos. Con base en los trabajos anteriores de diferentes aspectos relacionados con catalizadores metálicos heterogéneos, las perspectivas sobre las direcciones futuras hacia una mejor comprensión del comportamiento catalítico de diferentes entidades metálicas (átomos individuales, nanoagrupamientos y nanopartículas) de una manera unificadora también se han dado en esta tesis. / Les espècies metàl·liques de diferents dimensions (àtoms individuals, nanoclusters i nanopartícules) mostren diferents comportaments catalítics per a diverses reaccions catalítiques heterogènies. S'ha demostrat a la literatura que, molts factors que inclouen la mida de la partícula, la forma, la composició química, la interacció amb el suport metàl·lic, la reacció metàl·lica i la interacció amb dissolvents poden tenir influències significatives sobre les propietats catalítiques dels catalitzadors metàl·lics. Els desenvolupaments recents de metodologies de síntesi ben controlades i eines de caracterització avançada permeten relacionar les relacions a nivell molecular. En aquesta tesi, he realitzat estudis sobre catalitzadors metàl·lics d'àtoms únics a nanoclústers i nanopartícules. Mitjançant el desenvolupament de noves metodologies de síntesi, la mida de les espècies metàl·liques es pot modular i utilitzar com a catalitzadors model per estudiar l'efecte de mida sobre el comportament catalític dels catalitzadors metàl·lics per a l'oxidació de CO, hidrogenació selectiva, oxidació selectiva i fotocatàlisi. S'ha trobat que, els àtoms metàl·lics dispersos individualment i els clústers metàl·lics subnanomètrics poden aglomerar-se en nanoclústeres o nanopartícules més grans en condicions de reacció. Per millorar l'estabilitat dels catalitzadors subnanomètrics de metall, he desenvolupat una nova estratègia per a la generació d'àtoms i racimos en zeolites. Aquestes espècies metàl·liques subnanométricas són estables en tractaments de reducció d'oxidació a 550 oC. Després d'aquesta nova metodologia de síntesi, aquest nou tipus de materials poden servir com a model de catalitzador per estudiar l'evolució de les espècies metàl·liques subnanométricas en condicions de reacció. La transformació estructural de l'espècie Pn subnanométrica ha estat estudiada per microscòpia electrònica de transmissió in situ. S'ha demostrat que la mida de les espècies de Pt està fortament relacionada amb les condicions de reacció, que proporcionen idees importants per comprendre el comportament dels catalitzadors de subnanometria en condicions de reacció. En l'altra línia de recerca dels catalitzadors de metalls no nobles, he desenvolupat diverses estratègies generals per obtenir catalizadors de metalls no nobles recolzats en òxids metàl·lics o protegits per capes de carboni primes. Aquests materials presenten un excel·lent rendiment per a diverses reaccions importants, com la hidrogenació quimioelectiva de nitroarenes, fins i tot quan es comparen amb els catalitzadors convencionals de metall noble. En alguns casos, els catalitzadors de metalls no nobles poden fins i tot aconseguir selectivitats a productes no factibles que no s'han pogut assolir en catalitzadors de metall noble convencionals, que es deuen a la via de reacció diferent en catalitzadors de metalls no nobles. No obstant això, s'ha observat una espectroscòpia de fotoelèctria de raigs X amb pressió d'atmosfera que la irradiació lleugera pot modular la selectivitat als alcohols i hidrocarburs C2 +, la qual cosa obre una nova possibilitat per sintonitzar el comportament catalític dels catalitzadors metàl·lics. A partir d'aquests treballs de diferents aspectes relacionats amb els catalitzadors metàl·lics heterogenis, també s'ha donat en aquesta tesi perspectives sobre les futures orientacions cap a una millor comprensió del comportament catalític de diferents entitats metàl·liques (àtoms individuals, nanoclústers i nanopartícules). / Metal species with different size (single atoms, nanoclusters and nanoparticles) show different catalytic behavior for various heterogeneous catalytic reactions. It has been shown in the literature that, many factors including the particle size, shape, chemical composition, metal-support interaction, metal-reactant/solvent interaction, can have significant influences on the catalytic properties of metal catalysts. The recent developments of well-controlled synthesis methodologies and advanced characterization tools allow to correlate the relationships at molecular level. In this thesis, I have carried out studies on metal catalysts from single atoms to nanoclusters and nanoparticles. By developing new synthesis methodologies, the size of metal species can be modulated and used as model catalysts to study the size effect on the catalytic behavior of metal catalysts for CO oxidation, selective hydrogenation, selective oxidation and photocatalysis. It has been found that, singly dispersed metal atoms and subnanometric metal clusters may agglomerate into larger nanoclusters or nanoparticles under reaction conditions. To improve the stability of subnanometric metal catalysts, I have developed a new strategy for the generation of single atoms and clusters in zeolites. Those subnanometric metal species are stable in oxidation-reduction treatments at 550 oC. Following this new synthesis methodology, this new type of materials can serve as model catalyst to study the evolution of subnanometric metal species under reaction conditions. The structural transformation of subnanometric Pt species has been studied by in situ transmission electron microscopy. It has been shown that the size of Pt species is strongly related with the reaction conditions, which provide important insights for understanding the behavior of subnanometric metal catalysts under reaction conditions. In the other research line for non-noble metal catalysts, I have developed several general strategies to obtain non-noble metal catalysts either supported on metal oxides or protected by thin carbon layers. These materials show excellent performance for several important reactions, such as chemoselective hydrogenation of nitroarenes, even when compared with conventional noble metal catalysts. In some cases, non-noble metal catalysts can even achieve selectivities to unfeasible products which has not been possible to achieve on conventional noble metal catalysts, which is caused by the different reaction pathway on non-noble metal catalysts. Nevertheless, it has been revealed by ambient-pressure X-ray photoelectron spectroscopy that light irradiation can modulate the selectivity to alcohols and C2+ hydrocarbons, which opens a new possibility for tuning the catalytic behavior of metal catalysts. Based on the above works from different aspects related with heterogeneous metal catalysts, perspectives on the future directions towards better understanding on the catalytic behavior of different metal entities (single atoms, nanoclusters and nanoparticles) in a unifying manner have also been given in this thesis. / Liu, L. (2018). Heterogeneous Metal Catalysts: From Single Atoms to Nanoclusters and Nanoparticles [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/113169 / TESIS

Method selective laser melting can produce metal parts by using 3D printing. This diploma thesis deals with the influence of process parameters on the workability of AlSi9Cu3 high-strength aluminum alloy using selective laser melting. The theoretical part deals with relations between process parameters and identifies phenomena occurring during the processing of metals by this technology. It also deals with conventionally manufactured aluminum alloy AlSi9Cu3. In the work, material research is performed from single tracks tests, porosity tests with different process parameters and mechanical testing. Here are showing the trends of porosity change at scanning speed, laser power, individual laser stop distance, bulk energy, and powder quality. The workability of the material can be judged by the degree of relative density achieved. Simultaneously the values of the achieved mechanical properties of the selected process parameters are presented. The data obtained are analyzed and compared with literature.

Yes / The MIMO technology towards achieving future generation broadband networks design criteria is presented. Typical next generation scenarios are investigated. The MIMO technology is integrated with the OFDM technology for effective space, time and frequency diversity exploitations for high speed outdoor environment. Two different OFDM design kernels (fast Fourier transform (FFT) and wavelet packet transform (WPT)) are used at the baseband for OFDM system travelling at terrestrial high speed for 800MHz and 2.6GHz operating frequencies. Results show that the wavelet kernel for designing OFDM systems can withstand doubly selective channel fading for mobiles speeds up to 280Km/hr at the expense of the traditional OFDM design kernel, the fast Fourier transform.

Misophonia is a sensory disorder where specific stimuli, usually auditory, trigger the fight-flight-freeze response, causing extreme reactions, typically anger, panic, or anxiety. Research into treatment for misophonia is limited, primarily consisting of case studies applying common methods of therapy. However, research into similar disorders like tinnitus shows that there are many avenues of treatment that should be investigated, including audiological treatment. To apply audiological treatment to misophonia, selective noise cancelling must be used to control specific trigger sounds. In this research, a basic selective noise cancelling algorithm was developed using a convolutional neural network and was evaluated using a survey. Participants rated their reaction to trigger sounds, non-trigger sounds, and trigger sounds that had been selectively cancelled. The misophonic reactions to selectively cancelled sounds were significantly less than to trigger sounds. This shows that selective noise cancelling could be used to apply audiological treatments to misophonia.