Thesis (M.C.S.)--Carleton University, 2004. / Includes bibliographical references (p. 110-112). Also available in electronic format on the Internet.

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-06-11T17:44:49Z No. of bitstreams: 0 / Made available in DSpace on 2015-06-11T17:44:49Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:13/05492-9

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-06-11T17:44:49Z No. of bitstreams: 0 / Made available in DSpace on 2015-06-11T17:44:49Z (GMT). No. of bitstreams: 0 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / O presente trabalho abordou o sistema de Tomografia por Coerência Óptica (OCT) e sua aplicação à área de microfluídica. Para tanto, foram realizados testes de caracterização física de circuitos microfluídicos, utilizando modelos 3D (tridimensionais) construídos a partir de imagens de OCT destes circuitos. A técnica foi, assim, avaliada como potencial ferramenta de auxílio na aferição de microcanais. Indo além, este trabalho estuda e desenvolve técnicas de análise para fluxos microfluídicos, em especial técnicas baseadas no padrão de speckle. Em primeiro momento, métodos já existentes foram estudados e aprimorados, como o Speckle Variance OCT, em que foi obtido um ganho de 31% em tempo de processamento. Outros métodos, como o LASCA (Laser speckle Contrast Analysis), baseados na autocorrelação de speckle, são adaptados às imagens de OCT. Derivado do LASCA, o método de análise desenvolvido baseado na autocorrelação de intensidade motivou o desenvolvimento de um arranjo de OCT próprio e software de aquisição customizado, com taxa de amostragem da ordem de 8 kHz. O método proposto foi, então, capaz de distinguir fluxos volumétricos variados, e seus limites de detecção foram testados, comprovando sua viabilidade de aplicação para análise de movimento browniano e fluxos volumétricos abaixo de 10 μl/min. / Dissertação (Mestrado em Tecnologia Nuclear) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP / FAPESP:13/05492-9

The purpose of this Master's Project was to develop an Acid-Base Titration Simulator. It was also to be a part of the California State University - San Bernardino's GTSS, Generic Tutorial System for the Sciences, project. The main benefit is that students will be able to conduct titration experiments over the Internet without being in the laboratory and without costly equipment or dangerous chemicals. Instructors at the high school and college level can demonstrate the key principles of titration.

No description available.

I. An isothermal titration microcalorimeter having a colume of 4 ml and capable of temerature control to ±2 x 10-5°C is described. Major components include a constant temperature water bath controlled to ±3 x 10-4°C, a platinum reation vessel, and an isothermal control circuit consisting of constant Peltier thermoelectric cooling and variable Joule heating controlled by a thermistor in an AC Wheatstone bridge circuit. The calorimeter was tested by measuring the heat of ionization of water and was found to produce data accurate to ± 0.1% where small samples are used such as in the investigation of many biological systems.

The design, construction, and calibration of a precision thermometric titration calorimeter is described. This calorimeter was tested by determining the enthalpy change for ionization of water. The result, 13.34 ±0.03 kcal/mole (standard deviation), is in exact agreement with the best literature values. This standard deviation indicates that, using this calorimeter, ΔH values can be determined with an accuracy of ±0.0.5 kcal/mole. A calorimetric procedure has been developed for the, simultaneous determination of the equilibrium constant, the enthalpy change, and the entropy change for a chemical reaction from a single titration (Entropy Titration). This procedure has been tested by determining pK, ΔH, and ΔS for proton ionization from HPO42- and HSO4-. The method has also been used to determine pK, ΔH, and ΔS values for proton ionization from Adenosine and Ribese. The resultant pK tor each system has an accuracy of about ±0.05 pK unit. Enthalpy and entropy changes for proton ionization have been determined for twenty-six carboxylic acids. The results are discussed in terms of three previous approaches (i.e. inductive, electrostatic, and the linear relation between ΔH° and ΔS°). The results are shown not to fit any of these theories well and reasons for this are proposed. An alternate explanation is proposed based on the observed fit of the carboxylic acid data to a linear ΔG° vs ΔS° plot. The site of proton ionization from adenosine is established to be the ribose moiety. It is also shown that both the 2' and 3' hydroxyl groups are necessary for this acidity to exist in aqueous solution.

Bitumen acts as a binding agent in asphalt mixtures where it binds the aggregates together. It is known for its potential to heal small cracks and recover its mechanical properties under the right conditions. Though this self-healing property is known, there is currently a lack of knowledge about the mechanisms that drive the process. To optimize the use of this material for pavement design, the healing ability should be better understood and controlled. In this work, it is investigated how neutron imaging can be used to increase the understanding of the mechanisms behind the self-healing in bitumen. As a first step, the sample size requirement set by the measurement technique was determined. In order to detect micro cracks in bitumen by using this technique, the sample must be sufficiently small to allow neutron transmission. On the other hand, too small samples would complicate the structural analysis of the material since less information would be possible to obtain. Bitumen with different dimensions were scanned with neutrons to determine the maximum sample thickness. This work was followed by evaluating the healing capability of fractured bitumen and mastic samples, by using time series neutron tomography. The studied samples had a varying combination of hydrated lime (HL) filler concentration, crack volume, and contact area between the broken pieces. The data acquired from the time series tomography scans was analyzed using a three-dimensional analysis procedure including denoising, segmentation and volume measurements. From the volumetric analysis, it appeared that the initial crack size and crack shape have a large impact on the healing rate. It was found that bitumen, mastic with 20%, and 30% filler content had a similar healing behavior for relatively small crack volumes. When increasing the content of HL in the mastic, the healing rate decreases exponentially, with a drastic decrease after reaching a filler content of about 30%. / Bitumen fungerar som bindemedel i asfaltsblandningar där det binder ihop stenaggregaten. Bitumen är känd för sin förmåga att läka små sprickor och återfå sina mekaniska egenskaper under rätt förutsättningar. Trots att den självläkande egenskapen är välkänd, råder det idag en brist på kunskap om de mekanismer som ligger bakom denna process. För att optimera användandet av bitumen för vägbeläggningar behövs en bättre förståelse kring denna läkande egenskap. I detta projekt undersöks det hur neutronavbildning kan användas för att öka förståelsen kring de mekanismer som ligger bakom den självläkande egenskapen hos bitumen. Som ett första steg bestämdes provstorlekskravet för denna analysteknik. För att möjliggöra detekteringen av små sprickor i bitumen genom att använda denna teknik måste provmaterialet vara tillräckligt tunt för att neutronerna ska kunna transmitteras genom materialet. Allt för små provstorlekar skulle, å andra sidan, försvåra analysen av materialets struktur då informationen man kan erhålla blir mer begränsad. Bitumen med olika provstorlekar skannades med neutroner för att bestämma den maximala provtjockleken. Därefter analyserades den självläkande förmågan hos brutna bitumen- och bitumenmastixprover med tidsserie neutrontomografi. Prover med olika mängder av kalciumhydroxidfiller i bitumenblandningen, olika storlek på sprickvolymen och kontaktytan mellan de brutna provdelarna studerades. Data erhållna från experimenten användes för att göra en 3-dimensionell analys som inkluderade brusreducering av bilder, segmentering och volymmätningar. Från volymanalyserna konstaterades det att den initiala sprickstorleken och sprickformen har en stor inverkan på läkningstakten. Bitumen, mastix med 20%, och 30% filler-additiv uppvisade liknande läkningsegenskaper för relativt små sprickstorlekar. Vid en ökning av mängden filler material i mastixen minskar läkningstakten exponentiellt, med en drastisk minskning när man passerar en filler-koncentration på runt 30%. / <p>QC 210303</p>

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2016-06-22T11:34:19Z No. of bitstreams: 0 / Made available in DSpace on 2016-06-22T11:34:19Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Submitted by Daniela Maria de Toledo Ungaro (danielamt_ungaro@yahoo.com.br) on 2018-09-27T12:43:41Z No. of bitstreams: 1 Daniela Ungaro Finalizado para impressão.pdf: 3219565 bytes, checksum: 8ee8e24e21d6105d1be4113a492c91f5 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-09-27T14:48:02Z (GMT) No. of bitstreams: 1 ungaro_dmt_me_sjc.pdf: 3219565 bytes, checksum: 8ee8e24e21d6105d1be4113a492c91f5 (MD5) / Made available in DSpace on 2018-09-27T14:48:02Z (GMT). No. of bitstreams: 1 ungaro_dmt_me_sjc.pdf: 3219565 bytes, checksum: 8ee8e24e21d6105d1be4113a492c91f5 (MD5) Previous issue date: 2018-08-15 / Os objetivos deste estudo foram avaliar, com a ajuda de um modelo matemático, o tempo estimado para ocorrer reparo ósseo em dentes com lesão periapical tratados endodonticamente e comparar o volume da lesão periapical (em mm3) após a utilização de dois tipos de medicação intracanal. Para isso, foram selecionados 34 dentes unirradiculares com lesão periapical de pacientes da Disciplina de Endodontia do ICT/SJC-UNESP que necessitavam de tratamento endodôntico. Após a seleção dos dentes, foram obtidas radiografias periapicais (RP) e tomografias computadorizadas de feixe cônico (TCFC) antes de iniciar o tratamento endodôntico (T0). Os dentes foram divididos em dois grupos de acordo com a medicação intracanal utilizada (n=17): G1 – Hidróxido de cálcio associado à Clorexidina Gel 2% e G2 – Ultracal XS®. Foram obtidas novas radiografias periapicais e tomografias (TCFC) após o término do tratamento endodôntico (T1), sendo outras após 3 meses (T2) e também após 6 meses (T3). Os arquivos das tomografias foram exportados no formato DICOM (Digital Imaging and Communications in Medicine) para avaliar a volumetria das lesões pré e pós tratamento (em voxel/mm3) pelo processo de segmentação semiautomático em todos os períodos de tempo pré-estabelecidos (T0, T1, T2 e T3), por meio do software de livre acesso ITK-SNAP1.4.1 (University of North Carolina, Chapel Hill, NC, USA). Após a análise da volumetria das lesões periapicais em todos os períodos de tempo, os dados obtidos foram utilizados para construir um modelo matemático que foi empregado para estimar o tempo de reparo ósseo das lesões. Os dados obtidos foram analisados estatisticamente pelo Teste t - Student de amostras independentes (p<0,05). Houve diminuição do volume da lesão periapical nos casos tratados endodonticamente e a medicação intracanal utilizada, seja Hidróxido de cálcio + Clorexidina gel 2% ou Ultracal®, não apresentou diferença significativa no tempo de reparo ósseo nem no volume da lesão periapical nos períodos pré-determinados. Não houve diferença na estimativa de tempo de reparo ósseo entre os grupos avaliados, sendo, em média, 249 dias para o G1 e 245 dias para o G2. A utilização de um modelo matemático para estimativa de reparo ósseo pode ser uma alternativa viável na previsão do tempo de reparo dos casos tratados endodonticamente. / The objectives of this study were to evaluate the estimated time for bone repair in teeth with periapical lesions treated endodontically and to compare the volume of the periapical lesion (in mm3) with the help of a mathematical model after the use of two types of intracanal medication. For this, 34 single rooted teeth with periapical lesion were selected from patients of the Endodontic Discipline of the ICT/SJC-UNESP who needed endodontic treatment. After the teeth were selected, periapical radiography (RP) and cone-beam computed tomography (CBCT) were obtained before starting the endodontic treatment. The teeth were divided into two groups according to the intracanal medications used (n=17): G1 - Calcium hydroxide associated with 2% chlorhexidine gel and G2 – Ultracal XS®. New periapical radiographs and tomographys (CBCT) were obtained after endodontic treatment (T1), others after 3 months (T2) and after 6 months (T3). The files of CBCT were exported in DICOM (Digital Imaging and Communications in Medicine) format to evaluate the volumetry of pre and post-treatment lesions (voxel/mm3) by the semi-automatic segmentation process at all the pre-established time periods (T0, T1, T2, T3) through the free access software ITK SNAP-1.4.1 (University of North Carolina, Chapel Hill, NC, USA). After the analysis of the periapical lesion volume in all time periods, the data were used to construct a mathematical model that was used to estimate the bone repair time of the lesion. The data obtained were statistically analyzed by Student's t - test of independent samples (p <0.05). ). There was a decrease in the volume of the periapical lesion in endodontically treated cases and the intracanal medication used, whether calcium hydroxide + chlorhexidine gel 2% or Ultracal®, did not present a significant difference in bone repair time nor in the periapical lesion volume in the predetermined periods. There was no difference in the estimated bone repair time between the groups evaluated, being, on average, 249 days for G1 and 245 days for G2. The use of a mathematical model for estimation of bone repair may be a viable alternative in predicting the repair time of endodontically treated cases.