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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The prophetic structure of 1-2 Samuel

Patrick, James Earle January 2016 (has links)
The book of 1-2 Samuel, originally one scroll, is an episodic narrative recounting how the ancient Israelite monarchy was established around 1000 BC by the prophet Samuel and the kings Saul and David. For well over a century historical critics have sought to discern the process of its composition, proposing various conclusions with little consensus. Presently it is generally believed that several blocks of traditional material on common themes (e.g. the History of David's Rise) were brought together in the later pre-exilic period as part of the so-called Deuteronomistic History. This thesis chooses to begin with the present limits of 1-2 Samuel (without including, for example, 1Kgs 1-2), and undertakes to apply rhetorical analysis to all fifty-five chapters, episode by episode, each in its final-form position. The particular structural technique that has been discerned throughout this book is inverted parallelism with an unparalleled centre, here termed 'concentrism'. The unique contributions of this thesis are firstly a careful methodology for concentrism in Hebrew narrative, based on Hebrew poetic and oral composition and proposing specific criteria for identifying and verifying such structures. Secondly, the thesis attempts to account for the current position of every episode in the book, discerning how each contributes to the larger work as regards literary structure and rhetorical message. The resulting arrangement demonstrates an overall unity of technique and authorial perspective, focused on the themes of prophecy (hence the thesis title), deliverance from military attack, religious devotion and dynastic succession. The centre of this thesis therefore provides a detailed description of the discovered structure, one chapter for each of the book's two primary segments (1Sam 1 - 2Sam 6; 2Sam 7-24). A lengthy preceding chapter addresses various theoretical issues often raised relating to such concentric patterns (often inadequately labelled 'chiasmus'/'chiastic'). A summary chapter likewise follows the central chapters, revisiting themes of the methodology and drawing conclusions together. An initial chapter outlines past and present compositional theories, and a concluding chapter suggests further avenues of future research.
32

Exalação de radônio-222 em solos: parâmetros para modelagem e métodos de determinação

FARIAS, Emerson Emiliano Gualberto de 30 June 2016 (has links)
Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-08-15T22:41:28Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Emerson Emiliano Gualberto de Farias.pdf: 15008998 bytes, checksum: ec2d44d1a887b066298504f48ce92ee7 (MD5) / Rejected by Alice Araujo (alice.caraujo@ufpe.br), reason: on 2018-08-17T20:19:31Z (GMT) / Submitted by Pedro Barros (pedro.silvabarros@ufpe.br) on 2018-08-17T20:23:14Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Emerson Emiliano Gualberto de Farias.pdf: 15008998 bytes, checksum: ec2d44d1a887b066298504f48ce92ee7 (MD5) / Approved for entry into archive by Alice Araujo (alice.caraujo@ufpe.br) on 2018-08-17T20:55:02Z (GMT) No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Emerson Emiliano Gualberto de Farias.pdf: 15008998 bytes, checksum: ec2d44d1a887b066298504f48ce92ee7 (MD5) / Made available in DSpace on 2018-08-17T20:55:02Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) TESE Emerson Emiliano Gualberto de Farias.pdf: 15008998 bytes, checksum: ec2d44d1a887b066298504f48ce92ee7 (MD5) Previous issue date: 2016-06-30 / CNPq / Na Região Metropolitana do Recife (RMR), encontram-se rochas sedimentares de origem marinha denominadas fosforitos, cuja concentração de urânio aumenta com o teor de P₂O₅ (fosfato) dado o comportamento cristaloquímico similar desta substância. O impacto radiológico devido principalmente à presença de urânio em regiões com ocorrência de depósitos é decorrente da presença de ²²²Rn, um gás nobre formado pelo decaimento do ²²⁶Ra. Em vista disso, o presente trabalho foi desenvolvido com o objetivo de determinar as concentrações de fósforo e ²²⁶Ra, radionuclídeo gerador de ²²²Rn, em fosforitos uraníferos, e estudar os principais parâmetros referentes à exalação e ao poder de emanação de ²²²Rn neste tipo de rocha sedimentar. Para isso, o processo de transporte do gás radioativo na interface rocha/solo/atmosfera foi estudado em solos de Recife, Igarassu e Olinda, incluindo um estudo de caso no Refúgio Ecológico Charles Darwin, localizado em Igarassu, todos no estado de Pernambuco. A caracterização radiométrica do fosforito uranífero foi realizada por Espectrometria Gama de Alta Resolução. A determinação dos teores de fósforo, por outro lado, foi realizada por meio de Espectrometria de Absorção Atômica com Chama. Os ensaios de verificação dos detectores de radônio foram efetuados em uma câmara de calibração construída especificamente para este fim. O desempenho da câmara de calibração foi avaliado a partir da dupla-verificação para as medições de ²²²Rn pelo detector AlphaGUARD certificado pelo fabricante (SAPHYMO®) e comparando com os resultados esperados pelo modelo teórico. Para o estudo do poder de emanação de radônio, porção analítica de aproximadamente 10 g foi acondicionada em câmara de emanação de radônio com volume de 500 mL. A determinação do radônio no interior da câmara foi feita com o detector RAD7. Para o estudo de caso, a concentração de ²²²Rn no solo, sua permeabilidade e a taxa de exalação de radônio foram determinadas em solos florestais do Refúgio Ecológico Charles Darwin previamente selecionados a partir do cintilômetro portátil SRAT SP2 da Saphymo. Para as concentrações de ²²⁶Ra e fósforo no fosforito uranífero, as médias geométricas foram 677 Bq.kg⁻¹ e 2,51%, respectivamente, observando-se regressão linear positiva entre as variáveis em nível de 95% de confiança. A câmara de calibração para detectores de radônio mostrou-se uma ótima ferramenta para a verificação dos detectores AlphaGUARD e RAD7, que foram utilizados nos mais diversos estudos desta pesquisa. Os dados do poder de emanação obtidos neste trabalho são semelhantes aos reportados na literatura, indicando a adequação da metodologia utilizada. Quanto ao estudo de caso no Refúgio Ecológico Charles Darwin, o grau de conservação do solo, a permeabilidade e a concentração do radônio no solo revelaram-se como importantes parâmetros para o transporte do gás no sistema solo-ar. A pesquisa desenvolvida forneceu subsídios para a realização de futuros estudos sobre a determinação da fração de exalação de ²²²Rn em solos tropicais. / Sedimentary rocks of marine origin named phosphorites were found in the Metropolitan Region of Recife (MRR), in which uranium concentration increases with the P₂O₅ content (phosphate) due to the similar crystal chemical behavior. The radiological impact from enriched uranium regions is associated to the presence of ²²²Rn, a noble gas produced during the ²²⁶Rn decay from uranium series. Taking into account such importance, the present work was developed with the objective of determining the ²²⁶Ra (radon precursor) and phosphorus concentrations in uranium-phosphorites and studying the main parameters referring to the exhalation and emanation power of ²²²Rn in this sedimentary rock. For this, the transport process of the radioactive gas in the interface rock/soil/atmosphere was studied in soils from Recife, Igarassu and Olinda, including the study case in the Refúgio Ecológico Charles Darwin, located in the municipality of Igarassu, Pernambuco. The radiometric characterization of uranium-phosphorite was carried out by means of High Resolution Gamma-Ray Spectrometry. The determination of phosphorus contents, by the way, was accomplished by Flame Atomic Absorption Spectrometry. The verification assays of radon detectors were done in a calibration chamber especially constructed for this purpose. The performance of the calibration chamber was evaluated by means of double-verification for ²²²Rn measurements by the detector AlphaGUARD, with certification from Saphymo, and comparing with the expected results from the theoretical model. For the study of radon emanation power, an analytical portion of approximately 10 g was transferred to a radon emanation chamber with volume of 500 mL. The radon determination within the emanation chamber was carried out by means of the detector RAD7, also verified thorough the calibration chamber assays. For the study case, the soil concentration of ²²²Rn, its permeability and the radon exhalation rate were determined in forest soils from the Refúgio Ecológico Charles Darwin, previously selected by means the portable scintillometer SRAT SP2 from Saphymo. For the ²²⁶Ra and phosphorus concentrations, the geometric means were 677 Bq.kg⁻¹ and 2.51%, respectively, obtaining a positive linear regression between variables at the 95% confidence level. The calibration chamber was considered an excellent tool for verifying the AlphaGUARD and RAD7 detectors, which were used in the diverse studies of this research. The obtained data of emanation power were similar to those found elsewhere, corroborating the methodology here applied. According to the case study in the Refúgio Ecológico Charles Darwin, the conservation degree of soils, the permeability and the soil radon concentrations were very important parameters for the gas transport within the air-soil system. The developed research provides knowledge for developing further studies about the ²²²Rn exhalation fraction of tropical soils from uranium enriched regions.
33

Medida da contaminação radioativa do ar ambiental por radônio-222 e filhos em residências de Campinas-SP, Brasil

Neman, Rodrigo Silvestre 30 March 2000 (has links)
Orientadores: Julio Cesar Hadler Neto, Sergio Roberto de Paulo / Dissertação (mestrado) - Universidade Estadual de Campinas. Insituto de Fisica "Gleb Wataghin" / Made available in DSpace on 2018-07-27T04:22:18Z (GMT). No. of bitstreams: 1 Neman_RodrigoSilvestre_M.pdf: 481840 bytes, checksum: 8e393ca24a2477baba16d3eaaea80843 (MD5) Previous issue date: 2000 / Resumo: Nesta tese efetuamos a primeira aplicação de uma metodologia, desenvolvida em nosso grupo de pesquisa, para a monitoração da contaminação ambiental por Radônio-222 ( 222 Rn) e filhos. Esta aplicação se refere a uma medida de campo em Campinas-SP, onde foram expostos detetores plásticos (CR-39) em 70 residências em dois turnos de duração de seis meses cada, sendo um de verão e outro de inverno. Foram medidas tanto as atividades alfa devido a 222 Rn e filhos ( 218 Po e 214 Po) presentes no ar como as atividades alfa devido à deposição ("plate-out") dos filhos do radônio sobre superfícies materiais. Procurou-se fazer correlações entre as atividades medidas e características dasresidência e/ou da exposição. Com isso fomos capazes de estudar um pouco mais este tipo de contaminação e fatores que podem determinar sua magnitude. No texto também são apresentados os motivos que dificultam a medição desta contaminação, ressaltando com isso uma vantagem de nossa metodologia, que utiliza o detetor plástico, CR-39, como um espectrômetro para partículas alfa / Abstract: In this work we have employed for the first time a Monitoring Methodology, developed by our research group, to study Radon-222 ( 222Rn) and daughters environmental contamination. We carried out a survey in Campinas-SP, Brazil, exposing in the same rooms of 70 dwellings plastic detectors (CR-39) during two successive periods of 6 months: the first one from November/96 to May/97 and the second one from May/97 to December/97. The alpha activities due to 222 Rn and daughters ( 218Po and 214Po) in the air and due to Radon daughters plated-out on material surfaces have been measured and correlated with exposures and dwellings data. This procedure enabled an improvement on the knowledge of this contamination and factors that influence its magnitude . Finally, we have shown up the reasons that make the monitoring of Radon and daughters quite difficult, stressing the main advantage of our methodology, where the plastic detector, CR-39, is employed as an alpha spectrometer / Mestrado / Física / Mestre em Física
34

Medida separada de Radônio-222 e de seus filhos no ar : monitoração na cidade de Poços de Caldas-MG e comparação de atividades envolvendo 2 outras técnicas de medida de Rn-222 no ar

Neman, Rodrigo Silvestre 29 March 2005 (has links)
Orientador: Julio Cesar Hadler Neto / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Fisica Gleb Wataghin / Made available in DSpace on 2018-08-04T17:17:02Z (GMT). No. of bitstreams: 1 Neman_RodrigoSilvestre_D.pdf: 1415758 bytes, checksum: 9a19f979cde64f239b4b1cdeadc3726c (MD5) Previous issue date: 2004 / Resumo: Neste trabalho, uma medida das concentrações de radônio e filhos no ar foi conduzida em 39 residências de Poços de Caldas ¿ MG. Esta cidade é conhecida por apresentar altas taxas de radioatividade natural, despertando o interesse de medidas deste tipo. Três técnicas distintas para medir a concentração de radônio foram empregadas: i) técnica do dosímetro NRPB-SSI consistindo em uma câmara de difusão calibrada em câmara de radônio; ii) técnica desenvolvida em nosso grupo de pesquisa sendo uma câmara de difusão calibrada via emulsão nuclear; iii) técnica do carvão ativado. Os dosímetros i e ii foram expostos durante um período de 6 meses. Dentre as 39 residências, 10 foram sorteadas aleatoriamente para monitoração bimestral através da técnica iii. A intercomparação dos resultados das concentrações de radônio, para estas três técnicas, mostrou que as técnicas i e ii são compatíveis entre si e a técnica iii somente é compatível caso sejam observados alguns cuidados na exposição. Empregar a técnica do carvão ativado na forma originalmente proposta (uma única exposição durando aproximadamente uma semana) produz resultados que oscilam bastante. Ao considerar a média das quatro medidas para cada residência obtêm-se resultados mais confiáveis porém, ainda imprecisos, levando a necessidade de um uso mais intensivo desta técnica ao longo de vários meses. Além da concentração de radônio, a técnica ii também mede a concentração dos filhos no ar e a concentração de deposição. As concentrações de radônio obtidas por esta técnica variaram entre 40 e 330 Bq m -3 e o valor médio encontrado foi de 133 ± 11 Bq m -3 .As concentrações dos filhos no ar oscilaram entre 2 e 193 Bq m -3 e o valor médio encontrado foi de 53 ± 7 Bq m -3 . Uma correlação pobre entre a concentração do radônio e a dos filhos no ar foi encontrada, indicando a necessidade de medidas diretas dos filhos, os verdadeiros contaminantes, no lugar de predizê-las utilizando a concentração do pai e um fator de equilíbrio médio / Abstract: In this work the results of an intercomparison employing three distinct techniques for measuring indoor radon activity are discussed: i) NRPB-SSI dosimeter, a diffusion chamber, CR-39 based, calibrated in a controlled radon chamber; ii) our dosimeter, a diffusion chamber, CR-39 based, calibrated via nuclear emulsion; iii) activated charcoal technique. 39 dwellings of Poços de Caldas city (Minas Gerais State, Brazil), located in a high natural radioactivity region, have been monitored during a six month period. Dosimeters i e ii were exposed continuously in all the 39 dwellings and dosimeter iii was exposed 10 of them, randomly chosen. In this case the individual exposures lasted around 5 days and 4 equally time spaced exposures were made in each dwelling. Comparing each dwelling, results produced by techniques i and ii show a great level of concordance. Results of technique iii show fluctuations so that only their mean results statistically agree with the other techniques. In addition to radon activity, dosimeter ii is capable to assess time integrated radon daughters (RD) activities and plated-out activity. Radon activities ranged from 40 to 330 Bq m -3 and their mean value was 133 ± 11 Bq m -3 . Radon daughter activities in the air ranged from 2 to 193 Bq m -3 and their mean value was 53 ± 7 Bq m -3 . A poor correlation between radon activity and RD (the real contaminants) activity in the air was found, indicating the need to directily assess RD concentration instead of assess only radon concentration and employ mean value of equilibrium factor to predict RD concentration / Doutorado / Física / Doutor em Ciências
35

Estimation des émissions de gaz à effet de serre à différentes échelles en France à l’aide d’observations de haute précision / Estimation of greenhouse gases emission at different scales in France using high precision observations

Lopez, Morgan 16 November 2012 (has links)
L’objectif de ma thèse est de conduire et d’utiliser les observations de haute précision de gaz à effet de serre pour estimer les émissions de ces gaz à différentes échelles en France, du locale au régionale. Le réseau français de mesure de gaz à effet de serre, géré par l’équipe RAMCES, est constitué de trois observatoires équipés de systèmes de mesure par chromatographie en phase gazeuse. Ces chromatographes en phase gazeuse sont situés à Gif-sur-Yvette, Trainou (forêt d’Orléans) et au sommet du Puy-de-Dôme. Ils ont été optimisés pour la mesure continue et de haute précision des principaux gaz à effet de serre : CO2, CH4, N2O et SF6. Ayant installé le GC au Puy-de-Dôme au cours de l’année 2010, je présenterai et analyserai en détail la série temporelle obtenue depuis son installation. Les mesures de gaz à effet de serre et des traceurs associés m’ont permis d’utiliser une approche multigaz pour contraindre leurs émissions à différentes échelles. A une échelle départementale et régionale, j’ai utilisé le 222Rn comme traceur de masses d’air pour quantifier les flux surfaciques mensuels de N2O à Gif-sur-Yvette et Trainou. Les émissions annuelles de N2O estimées à Gif-sur-Yvette et Trainou sont respectivement de 0.34/0.51 et 0.52 g(N2O) m-2 a-1. Le cycle saisonnier des émissions de N2O a permis de mettre en évidence l’impact de l’agriculture sur les émissions lors de l’apport d’engrais azoté dans les sols. J’ai mis en évidence une corrélation entre les flux de N2O annuels et les précipitations annuelles à Gif-sur-Yvette. A une échelle locale, j’ai utilisé le CO2 et ses isotopes mesurés lors d’une campagne réalisée pendant l’hiver 2010 à Paris, pour estimer les flux de CO2 parisien. Les mesures de 14CO2 atmosphérique m’ont permis de montrer que les flux de CO2 parisien en hiver sont essentiellement anthropiques (77 %) avec une contribution significative des émissions biogéniques (23 %). L’analyse du 13CO2 à quant à lui mis en évidence que les 77 % d’émission de CO2 d’origine fossile sont dues à 70 % à l’utilisation de gaz naturel et 30 % à l’utilisation de pétrole. / The aim of my PhD is to use high precision measurements to evaluate greenhouse gas emissions at different scales in France, from local to regional. These measurements are made in the framework of the French greenhouse gases network operated by the RAMCES team. Three stations in France are equipped with gas chromatography measurement systems located at Gif-sur-Yvette, Trainou (Orléans forest) and on the summit of Puy-de-Dôme. They were optimized to measure continuously with high precision the main greenhouse gases: CO2 , CH4 , N2O and SF6. In July 2010, I have installed the gas chromatograph at Puy-de-Dôme and I present here the analysis of the past two years. I used an approach with measurements of greenhouse gases and related trace gases to constrain the emissions of greenhouse gases at different scales. At a regional scale, I used the 222Rn as an air mass tracer to quantify the monthly N2O fluxes at Gif-sur-Yvette and Trainou. Annual N2O emissions, derived from the atmospheric approach at Gif-sur-Yvette and Trainou are 0.34/0.51 and 0.52 g(N2O) m−2 a−1 , respectively. I found a clear seasonal cycle of N2O emissions with larger values in spring and summer, demonstrating the large contribution of agricultural emissions from fertilized soils. A correlation between annual N2O fluxes and annual precipitations was observed at Gif-sur-Yvette. At a local scale, I used carbon isotopes to estimate the fossil fuel CO2 contribution. Measurements were performed during a campaign in winter 2010 in Paris. Atmospheric 14 CO2 measurements showed that 77 % of total CO2 emissions are anthropogenic with a significant contribution of biospheric fluxes (23 %). Additionally, 13CO2 analysis showed that natural gas and fuel combustion amounted to 70 % and 30 %, respectively, of fossil fuel emissions.
36

Continuous Atmospheric Radon-222 Concentration Observation in East Asia

Moriizumi, Jun, Ohkuraa, Takehisa, Hirao, Shigekazu, Nono, Yuki, Yamazawa, Hiromi, Kim, Yoon-Shin, Guo, Qiuju, Mukai, Hitoshi, Tohjima, Yasunori, Iida, Takao 08 1900 (has links)
No description available.
37

Death of Jacob : narrative conventions in Genesis 47.28-50.26

Lee, Kerry Dwayne January 2014 (has links)
Regarding the structural logic behind Jacob’s death-bed story (Gen 47.28-50.26), biblical scholars historically have seen its enigmatic features as evidence of diachronic development. Those who treat it as an intentionally composed whole typically either simply assume that intention or else argue for it using only basic logical structures (chiasm, parallel). The story’s composition is better explained, however, through the lens of conventional structures, especially that of a Hebrew death-bed type-scene. In the first chapter I overview approaches to the passage in biblical scholarship and evaluate recent synchronic approaches. Structuralist readings of other biblical texts are considered and mostly dismissed as a precedent, though Propp’s method is similar. I then state my reasons for beginning with 47.28, rather than 47.27. In chapter two, I investigate the first of the four Episodes that make up Jacob’s death-bed story: 47.28-31. Specific issues addressed include: evidence of competing chronologies, phrasal similarities with the chosen-line genealogies of Genesis 5 and 11, and the characterization of Joseph as a Worthy Successor, one of four tale-roles taken by characters in death-bed stories. Chapter three deals with 48.1-22, giving special attention to the similarity of verses 3-12 to covenant-initiation forms, the issue of adoption, the conventional characterization of Joseph and his sons as Worthy Successors, and the grammar of verses 13-20. In chapter four I focus on the climactic aspects of the language of verse 28 and the characterization of all twelve sons as Worthy Co-Successors. Chapter five treats the Preparation and Testament sections (49.29-33) of the fourth and final Episode. Certain words and phrases are best understood in a legal register. In chapter six I turn to the extended conclusion of the fourth Episode, or the Epilogue, which encompasses the three short stories in 50.1-26. All three deal with conventional concerns typically addressed in death-bed stories. Furthermore, 50.22-26 is a conventional death-bed story in its own right. This investigation of conventional structures in Jacob’s death-bed story opens up new and more objective ways of understanding long-recognized problems in the passage as intentional elements, regardless of the process of the text’s composition and transmission.
38

Estabelecimento de metodologia para determinação de 222Rn por espectrometia de cintilação em líquido para aplicação em estudos de reservatórios de petróleo

Thiago César de Oliveira 18 April 2008 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The purpose of the present work is to develop an analytical methodology for the determination of 222Rn in surface water and in groundwater that will make possible the use of this radionuclide as a natural tracer in oil reservoirs. In secondary (or attended) oil recovery processes in oil fields, there is a necessity of developing new methods for labeling compounds that can act as tracers that can be used to obtain information on the performance of those procedures, aiming at their optimization. One other option that requires further tests is the utilization of naturally occurring radionuclides as radiotracers for this same purpose. The radioisotope 222Rn has been chosen for use as a tracer because it is an alpha emitter that is naturally produced in the reservoir rocks system and becomes partitioned in a well-defined proportion between the water and oil phases of the reservoir. The methodology that will be used for the quantification of the radon is based on the Liquid Scintillation Spectrometry (LSC) technique. This technique is one of the most sensitive methods of radiation counting, and the most used one for determining and quantifying alpha and beta radiation. The analyses of the standards and samples were carried using two distinct cocktail types: water miscible and immiscible, namely Ultima GoldTM AB and OptiscintTM cocktails, respectively. The efficiencies for each cocktail has been calculated, and this pointed to which cocktail performed better (in terms of better a/b separation and less interference). In this investigation a Liquid Scintillation Spectrometer Quantulus 1220 (Perkin Elmer) is used, provided with a pulse shape analyzer (PSA) that allows separate counting of a and b emissions. Care was taken during sample collection in order to minimize radon losses. For calibration of the Quantulus 1220 spectrometer, a 226Ra standard solution (SRM 4967A - NIST) with an activity of 2482 Bq g−1 was used. The effect of quenching and the interferences due to other radionuclides in the measurement have also been studied. Radon analyses were been performed both in surface water and groundwater. The samples were collected at the CDTN/CNEN premises, sited within the urban region in Belo Horizonte. / A proposta deste trabalho foi desenvolver uma metodologia analítica para determinação de 222Rn em água de abastecimento público e subterrânea, visando futuramente sua utilização em campos de produção de petróleo. Na produção secundária (ou assistida) do petróleo há a necessidade do desenvolvimento de novas técnicas e compostos que possam atuar como traçadores, visando maximizar a produção. O radioisótopo 222Rn foi escolhido para ser utilizado como traçador, por ser um emissor a natural, estar presente no sistema e particionar em proporções bem definidas entre as fases aquosa e oleosa. A metodologia empregada para a quantificação do radônio baseou-se na técnica de Espectrometria de Cintilação em Líquido (LSC ). Esta técnica é um dos métodos de contagem mais sensíveis, amplamente utilizado para detecção e quantificação das radiações alfa e beta. As análises dos padrões e amostras foram realizadas utilizando dois coquetéis distintos: Ultima GoldTM AB, miscível em água e OptiscintTM, imiscível em água. As eficiências para cada coquetel foram calculadas, determinando qual coquetel apresenta melhor performance (melhor separação a/b e menor interferência). O desenvolvimento deste trabalho utilizou o Espectrômetro Quantulus 1220 (Perkin Elmer), o qual possui um analisador de forma de pulso (PSA) que permite a separação de emissões alfa e beta. As coletas das amostras foram otimizadas visando minimizar a perda de 222Rn. Para calibração do espectrômetro Quantulus 1220, foi utilizado um padrão de 226Ra (SRM 4967A - NIST) com atividade de 2482 Bq g−1. Os efeitos de "quench"e possíveis interferências devido à outros radionuclídeos, no processo de extração, foram estudados. As análises de radônio foram realizadas em águas de abastecimento público e subterrânea. As coletas foram realizadas em Belo Horizonte, nas dependências do CDTN/CNEN.
39

Impactos da superestimulação ovariana sobre a diferenciação das células da granulosa bovina

Santos, Priscila Helena dos January 2017 (has links)
Orientador: Anthony César de Souza Castilho / Resumo: A superestimulação ovariana é uma biotecnologia amplamente empregada na espécie bovina para a obtenção de múltiplas ovulações. Com este objetivo diversos protocolos superestimulatórios surgiram, dentre eles o protocolo P-36 e sua variação, o protocolo P-36/eCG. Ambos os tratamentos utilizam o hormônio folículo estimulante (FSH) na indução do crescimento folicular. Como é acreditado que no último dia do tratamento, as células da granulosa folicular possuam receptores do hormônio luteinizante (LH; LHR), duas últimas doses de FSH foram substituídas pela administração de gonadotrifina coriónica equina (eCG; P-36/eCG). A molécula de eCG possui atividade tanto LH quanto FSH por se ligar a ambos receptores, aumentando a resposta ovulatória. Os dois tratamentos têm demonstrado eficácia quanto ao desenvolvimento de oócitos competentes para a produção embrionária, no entanto pouco se sabe sobre seus efeitos na diferenciação celular no folículo ovariano. Por isso, o presente estudo investigou os efeitos da superestimulação ovariana com FSH (P-36) ou FSH combinado com eCG (P-36/eCG) sobre aspectos bioquímicos e a produção de hormônios esteroides. Adicionalmente, quantificou-se a abundância de miRNAs reguladores da expressão do mRNA do LHR e outros miRNAs relacionados com o desenvolvimento folicular ovariano. Os resultados obtidos mostram que os tratamentos superestimulatórios alteram o perfil bioquímico intrafolicular e a concentração de estradiol no plasma. Aliado a isso, também alteram... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Ovarian overstimulation is a biotechnology widely used in the bovine species to obtain multiple ovulations. With this objective, several protocols were introduced, including the P-36 protocol and its variation, the P-36/eCG protocol. Both treatments use follicle stimulating hormone (FSH) to induce the follicular growth. As it is believed that on the last day of treatment, follicular granulosa cells have luteinizing hormone (LHR) receptors, two last doses of FSH have been replaced by administration of equine chorionic gonadotrifine (eCG; P-36/eCG). The eCG molecule has LH and FSH activity by binding to both receptors, increasing the ovulatory response. Both treatments has demonstrated efficacy in the development of oocytes competent for embryo production, however little is known about their effects on cell differentiation in the ovarian follicle. Therefore, the present study investigated the effects of ovarian superstimulation using FSH (P-36) or FSH combined with eCG (P-36/eCG) on biochemical aspects and production of steroid hormones. In addition, the abundance of miRNAs regulating the expression of LHR mRNA and other miRNAs related to ovarian follicular development. Results demonstrated that superstimulatory treatments alter the intrafollicular biochemical profile and the plasma estradiol concentration. In addition, they also alter the expression of LHR and miRNAs regulating LHR mRNA expression, possibly modulating ovulatory capacity in superstimulated ovarian follicles. / Mestre
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Methods of measuring the properties of ionized gases at high frequencies

January 1952 (has links)
Sanborn C. Brown, David J. Rose. / I. Measurements of Q / Sanborn C. Brown, David J. Rose -- II. Measurement of electric field / David J. Rose, Sanborn C. Brown -- III. Measurement of discharge admittance and electron density / Sanborn C. Brown, David J. Rose -- IV. A null method of measuring the discharge admittance / Lawrence Gould, Sanborn C. Brown. / January 22, 1952 -- v.1. / Includes bibliographies. / Army Signal Corps Contract no. DA36-039 sc-100, Project no. 8-102B-0. Dept. of the Army Project no. 3-99-10-022.

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