Master of Science / Department of Chemical Engineering / Jennifer L. Anthony / Zeolite refers to a microporous material, which is also called a molecular sieve. There are three major industrial applications of zeolites: adsorbents, ion exchangers, and catalysts; and many other minor applications including: sensors, agriculture, medicine, veterinary, hydrogen storage, fuel cells, microreactors, membrane reactors, and racemic separations. Today, zeolite is not limited to aluminosilicate. Researchers are attempting to use other species (such as B, Ga, Ge, Ti, and Zn) to replace aluminum in zeolites framework to accomplish particular applications. In 1991, the first zincosilicate zeolite was synthesized by Annen et al.. Currently, only four zincosilicate zeolites have been synthesized. Theoretically, zincosilicate should balance divalent cations better than aluminosilicate zeolites to provide a stronger acid site especially for hydrogen cracking reactions. Large pore VET type VPI-8 (Li₁.₉₁₄Zn₁.₉₁₄Si₁₅.₀₈₆O₃₄) is the most thermal stable of all the zincosilicate zeolites and has low chemicals cost, however, a high crystallinity VPI-8 required prohibitively long synthesis times or seeded synthesis procedures. In this work, a seed-free short time synthesis zincosilicate zeolite VPI-8 is presented. Methane, also known as natural gas, had become the largest abundant carbon reserve today, more than the amount of the fossil fuel including conventional gas, oil, and coal. Unlike fossil fuel, methane can be recycled from landfill. Methane could be used to produce useful and/or expensive chemicals via syngas conversion to fuel, paraffin, methanol, alcohol, and dimethoxyethane. In addition to pathways via a syngas intermediate, methane could react directly to ethylene, formaldehyde, and aromatics. Because syngas preparation and compression usually expends 60-70% of the capital cost and consumes almost all the energy of operation, more and more researchers are exploring direct methane activation. However, the high stability of methane is one of the limitations, and coking is another limitation. In this work, methane dehydroaromatization (MDA) over zincosilicate zeolite Li-VPI-8 and ion exchanged Ni/Li-VPI-8 are investigated, due to the stronger acid site in zincosilicate than aluminosilicate zeolites. This is the first time to study using zincosilicate as catalyst, capitalizing on the more efficient synthesis methods demonstrated in this work.

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Submitted by Cleide Dantas (cleidedantas@ufpa.br) on 2014-03-07T15:50:18Z No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseInfluenciaMonitoramento.pdf: 1998332 bytes, checksum: 3137599690b5b1f015ab9ab0c585c5ad (MD5) / Approved for entry into archive by Ana Rosa Silva (arosa@ufpa.br) on 2014-05-13T17:13:08Z (GMT) No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseInfluenciaMonitoramento.pdf: 1998332 bytes, checksum: 3137599690b5b1f015ab9ab0c585c5ad (MD5) / Made available in DSpace on 2014-05-13T17:13:08Z (GMT). No. of bitstreams: 2 license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Dissertacao_AnaliseInfluenciaMonitoramento.pdf: 1998332 bytes, checksum: 3137599690b5b1f015ab9ab0c585c5ad (MD5) Previous issue date: 2013 / Redes Ópticas Passivas estão cada vez mais difundidas como rede de acesso de banda larga. Devido à sua importância, tais redes necessitam constantemente de supervisão. Diversas técnicas vêm sendo empregadas para supervisão de redes ópticas, dentre as quais se destacam as que utilizam reflectometria, pois agregam vantagens, tais como: baixo custo, em comparação com outros métodos de supervisão, e não exigência de intervenção na casa do usuário. Esta dissertação apresenta uma estratégia capaz de quantificar, por meio de simulações, o impacto que a técnica de reflectometria no domínio do tempo gera como interferência em transmissões típicas de uma rede WDM-PON. / Passive Optical Networks are increasingly diffused as a broadband access technology. Due to their importance, such networks demands continue supervision scheme. Different techniques could be employed for Optical Network Supervision, among them those using reflectometry have highlighted, because it offer low cost when compared with other monitoring methods and do not require intervention in the user’s home. On the other hand, when doing monitoring, it is expected that this action does not influence the information signal transmitted to the subscriber. In this context, this work aims to quantify, through simulations, how the technique of time domain optical reflectometry interferes on the transmission of a WDM-PON network.

The ability to fabricate a charge-driven water pump is a crucial step toward mimicking the catalytic ability of natural enzyme systems. The first step towards making this water pump a reality is the ability to make a carbon nanotube (CNT) membrane with uniform, 0.8 nm pore diameter. Proposed in this work is a method for synthesizing these carbon nanotubes via VPI-5 zeolite templated, transition metal catalyzed pyrolysis. Using a membrane composed of these CNTs, it is possible to get water molecules to flow single file at a high flow rate, and to orient them in such a way that would maximize their ability to be catalyzed. Additionally, using the ability to plate a monolayer of precious metal catalyst molecules around the exit to the membrane, catalyst efficiency can be maximized by making every catalyst atom come into contact with a substrate molecule. In this work, we also demonstrate the ability to plate a monolayer of precious metal catalyst atoms onto an insulating, mesoporous, support material. By combining these two chemical processes, it is possible to mimic the catalytic efficiency of natural enzyme systems.

In this research an approach to all optical delta sigma modulator (ADSM) has been elaborated. Two important components of ADSM; "leaky integrator" and "inverted bi-stable quantizer" were modeled, on the basis of cross gain modulation of the Semiconductor Optical Amplifier (SOA). The simulations (via VPI photonics) were all in micrometer scale (suitable for chip fabrication). By simulating each element of ADSM the whole circuit was simulated and results have been showed and analyzed. By investigating the ADSM, the limiting factor for reaching higher frequencies (THz) was recognized to be the quantization device. Thus a new optical switch was introduced, for the first time so called "proteresis." By applying proteretic bi-stable device in the delta sigma modulator, the resonance frequency was improved minimum two fold from 295MHz to 575MHz without making any change in hysteretic bi-stable switch. The broad impact of this research is on the digital technologies that can be utilized in high-speed signal processing. The prime examples are the RF technologies used in military and civilian applications. Furthermore introduction of proteresis opens a new research gate for compensating delay in almost every system.

Made available in DSpace on 2016-04-18T21:39:47Z (GMT). No. of bitstreams: 4 Erik Aceiro Antonio1.pdf: 1548083 bytes, checksum: 089690da04ba664ec23f802cb3975826 (MD5) Erik Aceiro Antonio2.pdf: 1618157 bytes, checksum: efefcd4d6d658d457615e8757d4175d8 (MD5) Erik Aceiro Antonio3.pdf: 2722615 bytes, checksum: a3f70f5fd3c8b07408a62f1d5a6cfbc2 (MD5) Erik Aceiro Antonio4.pdf: 1214557 bytes, checksum: 8bf6858d70baeb72941ce7c5cc104437 (MD5) Previous issue date: 2008-06-30 / The advent of the Internet and the development of Information and Communication Technologies (ICT s)generated new spaces for communication and collaboration between groups of people in geographically distinct regions. The association of Web technology with instrument automation and control by computer has made possible the development of the so called Remote Laboratories or WebLabs - distributed environments that allow to access and control experiments remotely through a network or the Internet in real time and with the sensation of presence. In this work, a WebLab was developed for the study and caracterization of a WDM (Wave Division Multiplexing) system, aiming to support and complement activities in faceto-face and distance courses on Optical Communications. Drivers and graphic user interfaces (GUI s) were developed with the software LabVIEW for control and data acquisition of instruments used in a remote experiment to measure the basic features of a WDM system. An application was also developed with the software VPI for the numerical simulation of Bit Error Rate (BER) measurements. This work is part of the activities related to the participation of the Mackenzie Photonics Laboratory in the KyaTera Project of FAPESP s TIDIA Program. / O advento da Internet e o desenvolvimento das Tecnologias da Informação e Comunicação (TIC s) geraram novos espaços para a comunicação e colaboração entre grupos de pessoas localizadas em regiões geograficamente distintas. A associação da tecnologiaWeb com a automação e controle de instrumentos por computador tornou possível o desenvolvimento dos chamados Laboratórios Remotos ou WebLabs - ambientes distribuídos que permitem o acesso e controle remoto de experimentos através de uma rede de comunicação ou da Internet em tempo real e com sensação de presença. Neste trabalho, foi desenvolvido um WebLab para estudo e caracterização de um sistema WDM (Wave Division Multiplexing), destinado a apoiar e complementar atividades em cursos de Comunicações Ópticas presenciais e a distância. Foram desenvolvidos drivers e interfaces gráficas de usuário (GUI s) com o software LabVIEW para o controle e aquisição de dados dos instrumentos utilizados em um experimento remoto de medida das características básicas de um sistema WDM. Também foi desenvolvido um aplicativo com o software VPI que permite simular a medida da Taxa de Erro de Bit (BER) do sistema. Este trabalho é parte das atividades relacionadas à participação do Laboratório de Fotônica Mackenzie no Projeto KyaTera do Programa TIDIA da FAPESP.

Velofarynxinsufficiens (VFI) innebär en nedsatt förmåga att under tal och födointag stänga till mellan mun- och näshåla vilket leder till ett avvikande tal. Operation med svalglambå är en metod som kan användas för att behandla VFI och tidigare forskning har visat goda resultat avseende dess effekt på talet. Dock menar vissa forskare att operationen kan ha negativa effekter och att den bakomliggande orsaken till insufficiensen kan påverka graden av framgång. Aktuell studie ämnade undersöka huruvida operation med svalglambå påverkade talet vid VFI samt belysa om några skillnader fanns mellan olika patientgrupper avseende operationens effekt på tal. De olika patientgrupperna var (a) patienter med spalt, (b) patienter med spalt i kombination med ett syndrom eller en sekvens och (c) patienter med VFI utan förekomst av spalt. Eftersom tidigare studier dessutom indikerat att postoperativ talbehandling hos logoped kan vara relevant för vissa patienter undersöktes det också under vilka omständigheter det skedde. Journaler, inklusive perceptuella lyssnarbedömningar av talet genomförda av logopeder, och enkätsvar studerades för de 66 patienter som deltog. Dessa utgjorde 43,1% av alla 153 patienter som genomgått operation med svalglambå på Akademiska sjukhuset i Uppsala år 2000-2011. Talbedömningar genomförda före och ett år efter operation visade att talet förbättrades avseende förståelighet (p<0,001), hypernasalitet (p=0,005) och tryckreducerad artikulation (p=0,001) samtidigt som hyponasalitet inte ökade (p=0,55). Patienter med spalt i kombination med syndrom eller sekvens uppvisade större förbättring av hypernasalitet jämfört med de andra grupperna (p=0,037). 32 patienter gick i postoperativ talbehandling hos logoped och patienter med enbart spalt fick behandling i något högre utsträckning än patienter med gomspalt i kombination med syndrom eller sekvens. Kompensatorisk artikulation var den enda talavvikelsen vars förekomst kunde relateras till att patienten gick i postoperativ talbehandling. Resultaten indikerar att operation med svalglambå är en lämplig metod för att behandla VFI oavsett bakomliggande orsak. Nyckelord: Velofarynxinsufficiens, svalglambå, LKG, syndrom, primär VFI, talavvikelse, talbehandling / Velopharyngeal insufficiency (VPI) refers to the failure of separating the oral cavity from the nasal cavity during speech and deglutination. This leads to increased airflow through the nose and is the cause of resonance disturbances such as hypernasality and nasal emission. Previous studies evaluating the success of pharyngeal flap surgery to treat VPI have indicated satisfying result although some studies stress side effects due to postoperative constrictions. The underlying cause of VPI has been shown to influence the postoperative result. With this background we investigated the differences in speech, pre-, and one year post pharyngeal flap surgery and compared the three groups (a) cleft palate, (b) cleft palate in combination with a syndrome or a sequence, and (c) VPI without cleft palate. We also investigated the co-occurance of postoperative speech therapy regarding different speech parameters and the underlying cause of VPI. 66 of the 153 patients who underwent a pharyngeal flap surgery at Akademiska sjukhuset in Uppsala 2000-2011 agreed to participate in the study. 32 patients attended postoperative speech therapy. The data was collected through medical records and a survey and included perceptual analyses of speech pre-, and post surgery performed by speech and language pathologists. According to the results from the perceptual assessment, the pharyngeal flap surgery resulted in improved speech; intelligibility (p<0.001), hypernasality (p=0.005) and weak consonant pressure (p=0.001). Hyponasality did not increase significantly (p=0.55). Patients with cleft palate in combination with a syndrome or a sequence showed greater improvement regarding hypernasality (p=0.037). The only speech disturbance co-occurring with the presence of postoperative speech therapy was compensatory articulation. Patients with cleft palate seemed to receive postoperative speech therapy in a higher extent than patients with cleft palate in combination with a syndrome or a sequence. These results indicate that pharyngeal flap surgery is a successful way of treating VPI disregarding underlying cause. Keywords: Velopharyngeal insufficiency, pharyngeal flap, cleft palate, syndrome, primary VPI, speech deviation, speech therapy

Bile acids in the small intestines of animals serve to breakdown fats and fatsoluble vitamins. Most of the bile acids are reabsorbed into the enterohepatic circulation, but approximately five percent of these bile acids pass into the large intestine. These bile acids are swiftly deconjugated by the bacterial population, and then subjected to further intestinal bacterial chemical modifications. The most significant of these modifications are 7α-dehydroxylations which form secondary bile acids (deoxycholate and lithocholate). Much research has illuminated the 7α-dehydroxylation pathway: of particular interest is the bile acid inducible operon, for which Clostridium scindens VPI 12708 serves as the model organism. There is a lack of knowledge on how this operon is regulated, so the goal of this project was to create a genetic construct consisting of upstream regulatory elements, a bile acid inducible promoter, and a ϐ- glucuronidase reporter. Cloning strategies utilized PCR to amplify desired DNA fragments and sewing methodology to combine DNA fragments. DNA fragments were ligated into plasmids and transformed into competent E. coli. Transformants were evaluated for the desired reporter gene fusion by blue/white screening, additional PCR, and/or restriction digestion. The bile acid inducible promoter was successfully amplified, and the upstream sequence and uidA (ϐ- glucuronidase) reporter was demonstrated. However, no E. colitransformants were demonstrated to possess the baiP-uidA gene fusion. The project strategy is plausible and data regarding the bile acid inducible promoter are greatly needed.