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母親の主観性を捉える試み : 共通のビデオクリップを使用した実験的方法の妥当性SHIMA, Yoshihiro, UESHIMA, Natsumi, 島, 義弘, 上嶋, 菜摘 30 December 2009 (has links)
No description available.
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Gains and losses in the eyes of the beholder: a comparative study of foreign policy decision making under riskYang, Yi 12 April 2006 (has links)
Prospect theory is a descriptive model of individual decision-making under risk (Kahneman and Tversky 1979). The central tenet of prospect theory posits that the risk orientation of decision-makers is affected by the gains vs. losses domains in which they are situated. Individuals are predicted to be risk-averse in the domain of gains and risk seeking in the domain of losses. Although prospect theory made significant contributions to decision theory, it has important limitations. Foremost, as noted by Levy (1997a), prospect theory is not a complete theory of decision-making. Like rational choice theory, prospect theory attempts to explain choices or outcomes, not the processes through which those choices come about (Abelson and Levi 1985, 235).
In response to this limitation of prospect theory, this dissertation intends to address the following set of puzzles:
Do gains vs. losses domains affect the decision processes in foreign policy decision making? If so, in what way will decision strategies change? That is, what strategies are most likely to be employed when the decision maker is in the domain of gains? And, in contrast, what strategies are the most likely to be utilized when the decision maker is in the domain of losses?
To address these questions, I develop and extend prospect theory to account for the impact of gains vs. losses domains on decision strategy selections by decision makers under risk. A set of testable hypotheses are then derived.
To render a robust test of these hypotheses, I employ a cross-national experimental research design, utilizing American subjects first and then replicating the same experiment with subjects in mainland China. In terms of research instrument, I utilize the computerized decision process tracer  the Decision Board Platform. Specifically, the Âmoves of decision makers are recorded by the Decision Board and then used to identify choices and to infer specific decision strategies.
Statistical analysis of the experimental results demonstrates support for the major hypotheses. A decision maker in the domain of gains is more likely to employ a holistic, alternative-based, compensatory, and maximizing decision strategy than is a decision maker in the domain of losses.
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Price Leverage of Brand: Experiments on Product Categories and Information Quantity EffectsHuang, Hsin-i 09 February 2004 (has links)
Abstract
This study mainly investigated the changing of pricing leverage of brand among different situations, especially, among distinctive product categories and among various levels of product knowledge which consumers obtained. Firstly, the research tries to verify existence of the hypothesized pricing leverage of brand; that is to test (1) the influences of levels of brand awareness on consumers¡¦ price perception; and (2) the effect of brand awareness on consumers¡¦ tolerance over the price increasing. In addition, this research manipulates three other variables, namely: product category, product knowledge which consumer obtained, and consumers¡¦ involvement toward the product in interest, as to seek and explore the conditions on which the pricing leverage of brand can occur.
As experimentation is the method of this study, it utilizes a 3 ( brand awareness: high, middle, low) x 3 ( product category: convenience goods, shopping goods, specialty goods) x 2 ( product knowledge: much, little) x 2 (involvement: high, low) factorial design as its basic framework of experiment design. A focus group depth interview discussion, which participants were from target subject group, was held to collect the appropriate or suitable products, brands, pricing levels, product information, and product attributes, ... etc. The products eventually used in the experiments are six items: fresh milk, toilet tissue, hand-bag, leisure shoes, watch, and digital camera. According to the products chosen, the brand names are selected based on the levels of awareness in the markets in which the subject purchase. The subjects of the experiments are 144 students of National Sun Yat-sen University located in Kaohsiung, Taiwan. There are 815 entries of data obtained from the subject in the experiments.
Factor analysis, ANOVA, and MANOVA are used to analyze the data obtained from the experiment. The analysis findings support several propositional statements, including (1) the higher level of market awareness a brand enjoys, the higher price perception consumers acquire for it; (2) Among the difference product categories, the effect of price leverage of brand varies; (3) there is no influence from the magnitude of product knowledge which consumer obtained on the price leverage of brand.
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A Study of Crossflow Electro-microfiltration on the Treatment of Chimical Mechanical Polishing WastewaterTsai, Hsiu-Hui 16 September 2001 (has links)
ABSTRACT
In this study, two chemical mechanical polishing (CMP) wastewaters were treated by crossflow electro-microfiltration. Also studied are the effects of operation parameters on their treatment efficiencies. In the semiconductor industry, presently, CMP has become the key technique to provide global planarization on interlevel dielectrics (ILD) and metal layers of wafers. In general, the post-CMP cleaning process will produce a great quantity of CMP wastewater. Normally, CMP wastewater consists of abrasives of high concentration and stability, chemicals (e.g., oxidant and surfactant), and a tremendous mass of de-ionized water. Because of the negatively charged suspended solids in CMP wastewater, crossflow electro-microfiltration was used to treat this type of wastewater. By applying an electric field to the system, the negatively charged suspended solids were expelled from the membrane surface moving toward the anode. Not only reducing the cake formation on the membrane, enhancement of the filtration rate and permeate flux have also been found when an external electric field is applied to the filtration system. In this investigation, CMP wastewaters obtained from wafer fabs A and B were first characterized by various standard methods. In CMP wastewater A, the suspended solids were found to have a high negative zeta potential, about ¡V78 mV. Its electrical conductivity was determined to be 127.2 £gS/cm. Before testing, each CMP wastewater was pre-filtered using a filter paper of 1.2 £gm in pore size. An experimental design based on the Taguchi method was employed. The L9 orthogonal arrays were utilized to investigate the effects of four experimental factors ( i.e., electric field strength, crossflow velocity, transmembrane pressure, and membrane pore size) on the filtration rate and permeate quality in the crossflow electro-microfiltration system. When the electric field strength applied was lower than the critical electric field strength, increases of the electric field strength, transmembrane pressure, and membrane pore size were found to be beneficial to the filtration rate. The experimental results were further subjected to the analysis of variance and regular analysis. For both CMP wastewaters A and B, the electric field strength and membrane pore size were determined to be very significant parameters. In this filtration system, the optimal treatment efficiency could be achieved by using a higher electric field strength, lower crossflow velocity, higher transmembrane pressure, and larger membrane pore size. The quality of permeate thus obtained was even better than the tap water quality standards. Therefore, the permeate might be worth recycling for various purposes.
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The emergence of the Shenzhen Experimental School as an elite schoolChan, Ying-kit., 陳應杰. January 1994 (has links)
published_or_final_version / Education / Master / Master of Education
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O uso de cobogós como segunda pele em edifícios de escritórios: análise do desempenho lumínico de diferentes geometrias / The use of cobogos as second skin in office buildings: analysis of light performance of different geometriesCordeiro, Ana Carolina Aquareli 27 February 2018 (has links)
Uma das principais características do território brasileiro é a abundância de luz natural, recurso este que deve ser melhor aproveitado no interior das edificações. É fundamental que haja qualidade de iluminação natural incidindo nestes ambientes, principalmente se atividades visuais são desenvolvidas nestes locais. Por outro lado, a radiação solar direta também possui efeitos negativos, e o controle de sua incidência de forma direta nos ambientes internos se faz necessário. Dentro deste contexto, é relevante o uso de estratégias projetuais que, ao mesmo tempo que possibilitem o uso da luz natural, também protejam estes espaços internos da insolação direta, como os cobogós, elementos que permitem a passagem de luz natural e dos ventos, mas controla a incidência da radiação solar direta. O objetivo desta pesquisa é avaliar o desempenho lumínico em salas hipotéticas de escritórios, por meio da utilização de diferentes geometrias de cobogós, levando em consideração as diferentes latitudes, as orientações geográficas e as profundidades das salas. A metodologia consiste na análise do nível de iluminância e da uniformidade da luz nos ambientes estudados. Para este trabalho foram utilizados dois métodos: o método computacional, por meio do programa DIAlux e o método experimental, no qual foram avaliados modelos de escala. Primeiramente, foram apresentadas as análises obtidas por meio do programa computacional, que simulou quatro salas hipotéticas; duas delas tinham sua abertura composta somente com vidro, e as outras duas, a abertura continha, além do vidro, o cobogó como segunda pele. Para realizar as simulações foi empregada uma diversificada faixa de latitudes do território brasileiro (5ºN à 34ºS). Os resultados demostraram que os parâmetros projetuais como a utilização da sala sem cobogós (somente vidro), a geometria dos elementos vazados e a sua área de abertura, a orientação solar e os períodos analisados (verão e inverno) exerceram uma influência significativa na distribuição e no redirecionamento da luz no ambiente interno das salas estudadas. Com relação ao desempenho de luz no ambiente, o caso 1, entre todos os outros estudados, foi o que mostrou ser mais eficiente e atendeu melhor o requisito de iluminância interna, apesar de se verificar pontos com luminosidade acima de 2000 lux, principalmente na fachada Oeste e no final da tarde. Posteriormente, foram avaliados e comparados os dados 8 simulados com os dados medidos em um modelo de escala, averiguando duas situações definidas: o caso de referência e um dos casos de cobogós para a cidade de São Carlos. Os resultados obtidos por meio do programa DIAlux garantiram valores mais próximos do ideal, já que neste software foram inseridos a latitude, a hora, a orientação, e demais dados que não irão sofrer influências externas. Em contrapartida, o método experimental revelou-se uma ferramenta útil na visualização da distribuição espacial da luz no ambiente estudado. Como conclusão do trabalho, comprovou-se que os cobogós são eficazes dispositivos de sombreamento, pois controlam altos níveis de iluminância em comparação aos ambientes que não apresentaram esses elementos de proteção. / One of the main characteristics of the Brazilian territory is the abundance of natural light, a resource that should be better utilized inside the buildings. It is fundamental that there is quality of natural lighting focusing on these environments, especially if visual activities are developed in these places. On the other hand, the direct solar radiation also has negative effects, and the control of its incidence directly in the internal environments becomes necessary. Within this context, it is important to use design strategies that, while allowing the use of natural light, also protect these indoor spaces from direct sunlight, such as cobogos, elements that allow the passage of natural light and winds, but controls the incidence of direct solar radiation. The objective of this research is to evaluate light performance in hypothetical office rooms through the use of different pavement geometries, taking into account the different latitudes, geographic orientations and depths of the rooms. The methodology consists in the analysis of the level of illuminance and the uniformity of light in the studied environments. For this work two methods were used: the computational method, through the DIAlux program and the experimental method, in which scale models were evaluated. Firstly, the analyzes obtained through the computational program, which simulated four hypothetical rooms, were presented; two of them had their opening composed only of glass, and the other two, the opening contained, besides the glass, the cobogó as second skin. In order to carry out the simulations a wide range of latitudes of the Brazilian territory (5ºN to 34ºS) was employed. The results showed that the design parameters such as the use of the room without cobogos (glass only), the geometry of the leaked elements and their opening area, the solar orientation and the analyzed periods (summer and winter) exerted a significant influence on the distribution and in the redirection of the light in the internal environment of the rooms studied. Regarding the performance of light in the environment, case 1, among all others studied, was shown to be more efficient and better met the requirement of internal illuminance, although points with brightness above 2000 lux, especially in the facade West and late afternoon. Subsequently, the simulated data were compared with the data measured in a scale model, checking two defined situations: the case of reference and one of the cases of cobogos for the city of São Carlos. The results obtained through the DIAlux program 10 guaranteed values closer to the ideal, since in this software were inserted latitude, time, orientation, and other data that will not suffer external influences. In contrast, the experimental method proved to be a useful tool in visualizing the spatial distribution of light in the studied environment. As a conclusion of the work, it was verified that the cobogos are effective shading devices, because they control high levels of illuminance in comparison to environments that did not present these elements of protection.
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Método de Espectroscopia de Mistura de Níveis para Medida de Momentos de Quadrupolo Nucleares / Level Mixing Spectroscopy method to measure the Nuclear Quadrupole MomentumKliewer, Marcus 20 August 1999 (has links)
Momentos de quadrupólo elétricos de estados isoméricos nucleares com vidas médias entre 10 nanosegundos e 100 milisegundos podem ser medidos com o método Espectroscopia de Mistura de Níveis (Level Mixing Spectroscopy- LEMS), utilizando campos magnéticos variáveis aplicados em núcleos implantados em materiais hospedeiros que possuam gradientes de campo elétrico. O Campo magnético externo pode ser substituido pelo campo hiperfino de materiais ferromagnéticos e sua variação poderia ser controlada variando a temperatura. O objetivo deste trabalho é verificar a viabilidade desta substituição. Implementamos o método LEMS no Laboratório Pelletron usando como caso teste o estado isomérico de 398 KeV do 69Ge que possui todas as suas propriedades nucleares conhecidas (meia vida, spin, momento magnético, momento de quadrupolo elétrico). Ele foi produzido pela reação 56Fe(16O, 2pn)69Ge com o feixe de 16O à 53 MeV (LAB) de energia, e depois implantado em Gadolínio que é ferromagnético abaixo de Tc = 289K. Medimos a anisotropia da radiação gama emitida por esse núcleo em função da temperatura. A comparação entre as medidas da anisotropia em função da temperatura, com medidas da anisotropia em função do campo magnético externo, feita pelo grupo de Leuven/Bélgica, nos levou a duas interpretações possíveis. Na primeira, supondo a interação elétrica constante e independente da temperatura, obtemos um campo magnético hiperfino anômalo para o Gd. Na segunda análise, obtivemos o campo hiperfino variando linearmente com a magnetização, admitindo gradientes de campo elétrico dependentes da temperatura. Medidas futuras usando monocristal de Gd poderão resolver esta ambiguidade, bem como medidas TDPAD (Time Diferencial Perturbed Angular Distribuition) em função da temperatura, na qual se mede diretamente o campo hiperfino. / The Level Mixing Spectroscopy method allows to measure the eletric quadrupole moments of high spin isomeric nuclear states (10ns < t < 100ms) produced in nuclear reactions. The magnetic interaction is usualy created by an intense external magnetic field. The eletric quadrupole interaction can be created by recoi-implantation of the nuclei in non-cub crystals, used as hosts. The external magnetic field can then be replaced by the hiperfine fields of ferromagnetic materials, controling its intensity by temperature variation. The purpose of the research performed for this work is to verify the viability of this replacement. We adapt the LEMS method to be used in the Pelletron Laboratory. We choose the isomeric state at 398 KeV exitation energy in the 69Ge nucleus as a test case, because it has all nuclear properties well known (half-life, spin, magnetic moment, eletric quadrupole moment). It was produced by the 56Fe(16O, 2pn)69Ge reaction, with a 16O beam at 53 MeV, and implanted and stopped in a Gadolinium host, which is a ferromagnet from low temperatures up to Tc=289 K. We measure the anisotropy of the emitted gama ray as a function of the temperature of the host. The comparison of this measurement with another of the anisotropy as a function of an external magnetic field strength, done by the Leuven/Belgium group, show us two possibilities. In the first, we suppose that the eletric interaction is cosntant and independent of temprature and we obtain an anomalous magnetic hyperfine field for Gd. In the second one, we obtain a hyperfine field that follows the magnetization if we assume eletric field gradientes that are temperature dependent. New measurements by using Gd monocrystal and the TDPAD (Time Diferencial Perturbed Angular Distribution) method may solve this ambiguity.
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La représentation de l'acte violent et le rapport à la violence chez la personne incarcérée pour délit ou crime, quel outil psychothérapique ? : investigations phénoménologique et psychanalytique auprès de détenus en Martinique / The representation of the violent acts and the relation to violence in individuals incarcerated for misdemeanors and other offenses, which psychotherapeutic tool ? : Phenomenological and psychoanalytical research of prisoners in MartiniqueLina, Victor 12 December 2017 (has links)
Partant d’une pratique clinique en milieu pénitentiaire, nous nous sommes rendus compte de l’importance de la violence tant de celle contenue dans les motifs d’incarcération que celle amenée comme une énigme silencieuse dans les problématiques subjectives pouvant se faire entendre à la faveur des entretiens à visée thérapeutique que nous avons avec les personnes incarcérées.Au moyen d’outils prélevés dans des champs de recherche se référant à la méthode expérimentale, nous avons procédé à des observations et les avons traduites au moyen de traitements statistiques pour en tirer des conclusions faisant écho aux hypothèses formulées en amont. Cette approche a été confrontée à celle de la clinique en psychologie en prenant appui sur l’analyse et la construction de cas. Des cas et vignettes ont été exposés dans le but d’en prélever la part transversale ou généralisable d’un fonds singulier.Cette méthodologie comparative est utilisée comme une opportunité pour nous permettre d’interroger le choix épistémologique parfois implicite auquel nous nous sommes référés. Ce détour s’est présenté comme une nécessité didactique, propice, à consolider notre désir de savoir et, à être soumis à un examen critique.Ce parcours heuristique nous a permis de mettre à l’étude les énigmes toujours particulières que nous lègue chaque patient et parmi elles, des blessures anciennes et silencieuses qui accompagnent un malaise postcolonial dont l’un des modes prévalents d’expression sans parole est l’agir violent. Ce qui ne fait pas équivaloir l’agir violent à une maladie mais à une rupture en quête de sens ou encore à une manifestation d’un défaut de sens.Le travail thérapeutique avec les personnes détenues reçues comme patients montre que le traitement par la parole peut être une opportunité pour initier une autre forme d’élaboration subjective par le truchement d’un moment de reconnaissance. / Initiating from a clinical practice at a penitentiary, we realized the importance of violence both on grounds for incarceration and presented as a silent enigma in the subjective problems that can be heard through therapeutic interviews that we have with prisoners.Using tools taken from research fields based on the experimental method, observations were made and translated using statistical methods to draw conclusions in relation with the hypothesis formulated beforehand.This approach was compared with that of clinical psychology supported by analysis and case construction. Cases and thumbnails have been exhibited in order to extract the common factor of a singular framework.This comparative methodology’s purpose allow us to interrogate the sometimes implicit epistemological choice by which we are driven. This detour presented itself as a didactic necessity, conducive at consolidating our desire to know and to be subjected to a critical examination.This heuristic path allowed us to study the ever-present enigmas left to us by each patient and among them the old and silent wounds that accompany postcolonial discomfort, one of the prevalent modes of speechless expression is act violently. This does not equate violent action as a disease but as a fracture in the search for meaning or as a demonstration of a deficience of meaning.The therapy sessions of the detainees received as patients shows that treatment via speech can be an opportunity to initiate another form of subjective elaboration through a moment of recognition.
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Efeitos de uma intervenção em grupo em habilidades sociais para universitários na perspectiva da análise do comportamento / Effects of a group intervention on social skills for college students from the perspective of behavioral analysisMoretto, Laísa Aparecida [UNESP] 05 October 2017 (has links)
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Previous issue date: 2017-10-05 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O termo habilidades sociais (HS) é utilizado para indicar um conjunto de comportamentos aprendidos e necessários nas interações sociais. O estudo das habilidades sociais e suas aplicações torna-se relevante porque tais comportamentos colaboram para desempenhos sociais satisfatórios. A universidade exige diversos repertórios dos alunos, incluindo os interpessoais, contudo, a literatura ainda carece de estudos experimentais quanto a efeitos de intervenções. Este estudo objetivou avaliar os efeitos de um treinamento de habilidades sociais para universitários em dois desenhos experimentais: o experimental de grupo e o delineamento de linha de base múltipla de sujeito único. No estudo experimental de grupo participaram 14 universitários, 9 no Grupo Experimental (GE) e 5 no Grupo Controle (GC), avaliados quanto à HS e saúde mental (SM). O GE foi avaliado no pré-teste, passou pela intervenção, em seguida pelo pós-teste e, seis meses depois, seguimento. Enquanto que, o GC passou pela avaliação de linha de base (LB) 1 e, 3 meses depois, período que o grupo experimental passava pela intervenção, a LB 2. O tratamento dos dados, utilizando estatísticas descritivas e inferenciais, apontou melhora significativa para o GE nas avaliações de pós-teste e seguimento. A mesma análise entre as LB 1 e LB 2 do GC não indicou mudança estatisticamente significativa, sugerindo que os ganhos do GE podem ser atribuídos à intervenção. Assim, os dados expõem ampliação do repertório de HS e diminuição de indicadores de ansiedade e depressão apenas no GE. O estudo com delineamento de ensaio clínico randomizado contou com a participação de 5 universitários, avaliados no âmbito das HS e de SM. Os universitários foram avaliados na LB 1, três meses depois na LB 2, passaram pela intervenção, pós-teste e, seis meses depois, reavaliados no seguimento. Os resultados não apontaram mudanças significativas entre as avaliações de LB 1 e 2, já entre LB 2 e pós-teste, há indicativos de ampliação do repertório de HS, principalmente dos participantes que fizeram as tarefas de casa, e melhora em indicadores de SM, também foi observada a manutenção de resultados no seguimento. De maneira geral, os dados de pós-teste e, principalmente, de seguimento indicaram que a intervenção teve efeitos na promoção do repertório de HS e na redução de sintomas de ansiedade e depressão em universitários. Diante disso, discute-se a validade da intervenção descrita neste estudo enquanto política pública a ser adotada para os anos iniciais da universidade. / The term social skills are used to indicate a set of behaviors learned and needed in social interactions. The study of social skills and their applications become relevant because such behaviors contribute to satisfactory social performance. The university requires diverse student repertoires, including the interpersonal ones, and the literature still lacks experimental studies on the effects of interventions. This study aimed to evaluate the effects of a social skills training for university students in two experimental designs: the experimental group and the single subject multiple baseline design. In the experimental group study, 14 university students participated, 9 in the Experimental Group (EG) and 5 in the Control Group (CG), evaluated for social skills and mental health. The EG was evaluated in the pre-test, followed by the intervention, then by the post-test and, six months later, follow-up. Meanwhile, the GC underwent baseline assessment (BL) 1 and, 3 months later, the period the experimental group went through the intervention, BL 2. Data treatment, using descriptive and inferential statistics, indicated a significant improvement for the EG in the post-test and follow-up evaluations. The same analysis between the BL 1 and LB 2 of the CG did not indicate a statistically significant change, suggesting that the gains of the EG can be attributed to the intervention. Thus, the data show an increase in the social skills repertoire and a decrease in anxiety and depression indicators in the EG alone. The study with a randomized clinical trial design consisted of the participation of 5 university students, evaluated in the scope of social skills and mental health. The students were evaluated in LB 1, three months later in LB 2, underwent the intervention, post-test and, six months later, reassessed in the follow-up. The results did not indicate significant changes between the LB 1 and 2 assessments, between LB 2 and post-test, there are indicative of the expansion of the social skills repertoire, mainly of the participants who did the housework, and improvement in mental health indicators, maintenance of follow-up results was also observed. In general, post-test data, and mainly follow-up data, indicated that the intervention had effects on the promotion of HS repertoire and the reduction of anxiety and depression symptoms in university students. Therefore, the validity of the intervention described in this study is discussed as a public policy to be adopted for the initial years of the university.
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Método de Espectroscopia de Mistura de Níveis para Medida de Momentos de Quadrupolo Nucleares / Level Mixing Spectroscopy method to measure the Nuclear Quadrupole MomentumMarcus Kliewer 20 August 1999 (has links)
Momentos de quadrupólo elétricos de estados isoméricos nucleares com vidas médias entre 10 nanosegundos e 100 milisegundos podem ser medidos com o método Espectroscopia de Mistura de Níveis (Level Mixing Spectroscopy- LEMS), utilizando campos magnéticos variáveis aplicados em núcleos implantados em materiais hospedeiros que possuam gradientes de campo elétrico. O Campo magnético externo pode ser substituido pelo campo hiperfino de materiais ferromagnéticos e sua variação poderia ser controlada variando a temperatura. O objetivo deste trabalho é verificar a viabilidade desta substituição. Implementamos o método LEMS no Laboratório Pelletron usando como caso teste o estado isomérico de 398 KeV do 69Ge que possui todas as suas propriedades nucleares conhecidas (meia vida, spin, momento magnético, momento de quadrupolo elétrico). Ele foi produzido pela reação 56Fe(16O, 2pn)69Ge com o feixe de 16O à 53 MeV (LAB) de energia, e depois implantado em Gadolínio que é ferromagnético abaixo de Tc = 289K. Medimos a anisotropia da radiação gama emitida por esse núcleo em função da temperatura. A comparação entre as medidas da anisotropia em função da temperatura, com medidas da anisotropia em função do campo magnético externo, feita pelo grupo de Leuven/Bélgica, nos levou a duas interpretações possíveis. Na primeira, supondo a interação elétrica constante e independente da temperatura, obtemos um campo magnético hiperfino anômalo para o Gd. Na segunda análise, obtivemos o campo hiperfino variando linearmente com a magnetização, admitindo gradientes de campo elétrico dependentes da temperatura. Medidas futuras usando monocristal de Gd poderão resolver esta ambiguidade, bem como medidas TDPAD (Time Diferencial Perturbed Angular Distribuition) em função da temperatura, na qual se mede diretamente o campo hiperfino. / The Level Mixing Spectroscopy method allows to measure the eletric quadrupole moments of high spin isomeric nuclear states (10ns < t < 100ms) produced in nuclear reactions. The magnetic interaction is usualy created by an intense external magnetic field. The eletric quadrupole interaction can be created by recoi-implantation of the nuclei in non-cub crystals, used as hosts. The external magnetic field can then be replaced by the hiperfine fields of ferromagnetic materials, controling its intensity by temperature variation. The purpose of the research performed for this work is to verify the viability of this replacement. We adapt the LEMS method to be used in the Pelletron Laboratory. We choose the isomeric state at 398 KeV exitation energy in the 69Ge nucleus as a test case, because it has all nuclear properties well known (half-life, spin, magnetic moment, eletric quadrupole moment). It was produced by the 56Fe(16O, 2pn)69Ge reaction, with a 16O beam at 53 MeV, and implanted and stopped in a Gadolinium host, which is a ferromagnet from low temperatures up to Tc=289 K. We measure the anisotropy of the emitted gama ray as a function of the temperature of the host. The comparison of this measurement with another of the anisotropy as a function of an external magnetic field strength, done by the Leuven/Belgium group, show us two possibilities. In the first, we suppose that the eletric interaction is cosntant and independent of temprature and we obtain an anomalous magnetic hyperfine field for Gd. In the second one, we obtain a hyperfine field that follows the magnetization if we assume eletric field gradientes that are temperature dependent. New measurements by using Gd monocrystal and the TDPAD (Time Diferencial Perturbed Angular Distribution) method may solve this ambiguity.
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