he extent of BiInO₃ substitution in the perovskite system xBiInO(₃)-(1 - x)PbTiO₃ and the corresponding raise in the transition temperature were investigated using thermal analysis, dielectric measurements, x-ray diffraction, and electron microscopy. Maximum tetragonal perovskite distortion (c/a = 1.082) was obtained for x = 0.20, with a corresponding Curie temperature of 582°C. Phase-pure tetragonal perovskite was obtained for x less than or equal to 0.25. Compound formation after calcining mixed oxide powders resulted in agglomerated cube-shaped tetragonal perovskite particles, which could be fired to 94.7% of theoretical density (TD). Niobium-modified BIPT ceramics with PT contents of 80% and 85% were found to possess significantly lower dielectric loss at elevated temperatures, making it possible to polarize the materials. Piezoelectric properties were measured for a 1.5 mol% Nb -0.15BI-0.85PT composition with a transition temperature of 542°C; the longitudinal piezoelectric coefficient and coercive field were found to be 60 pC/N and 125 kV/cm, respectively. Compositions of xBiLaO₃-(1 − x)PbTiO₃ over the range 0 < x < 0.225 were calcined and sintered. Dielectric constant with temperature and differential scanning calorimetry measurements were in excellent agreement with respect to a Curie-like tetragonal to cubic transformations starting at 495°C for pure PbTiO₃, shifting to lower temperatures with increasing x. For compositions of x > 0.05, a second higher-temperature (∼600°C) endotherm, and matching dielectric anomaly, were consistently observed, for which there were no structural changes indicated by hot-stage x-ray diffraction. This transformation was interpreted to be similar to a Curie transformation in relaxor ferroelectrics in which localized segregation of B-site cations (below the resolution limit of x-ray diffraction) facilitated ferroelectric behavior.

Neste trabalho foram feitas medidas da impedância complexa dos compostos Heusler Pd2MnSn e Pd2MnSb em função da freqüência, temperatura e campo magnético próximo à temperatura de Curie (Tc). Através de análise computacional dos dados, a magnitude da permeabilidade magnética complexa inicial foi obtida assim como sua dependência com a temperatura, freqüência e campo magnético externo. Ambas as componentes real (μ ') e imaginária (μ ") da permeabilidade magnética apresentam máximos pouco abaixo de Tc. Em baixas freqüências esse efeito é mais pronunciado em Pd2MnSn. Nós atribuímos os altos valores obtidos de μ ' nesse composto a uma alta densidade de paredes de domínio gerada por fronteiras de anti-fase (APBs). A dependência da permeabilidade com a freqüência mostra um comportamento relaxacional. Para o composto Pd2MnSn esse comportamento é bem descrito através da fórmula de Debye modificada comα ~ 0,3. Esse comportamento é característico de um sistema onde domínios magnéticos têm uma distribuição com uma ampla faixa de tamanhos que não muda significativamente quando a temperatura se aproxima de Tc. / In this work measurements of the complex impedance of the Heusler compounds Pd2MnSn and Pd2MnSb were made as a function of frequency, temperature and magnetic field near the Curie temperature (Tc). By computational analysis of the experimental data, the magnitude of the complex initial magnetic permeability was obtained as well as its temperature, frequency and external magnetic field dependencies. Both the real (μ ') and the imaginary (μ ") components of the magnetic permeability show maxima just below Tc. In low frequencies this effect is more pronounced in Pd2MnSn. We attribute the high values of μ ' obtained in this compound to a high density of domain-wall generated by anti-phase boundaries (APBs). The frequency dependence of the permeability shows a relaxational behavior. For the Pd2MnSn compound this behavior is well described by a modified Debye formula with α ~ 0,3. This behavior is characteristic of a system where magnetic domains are distributed within a large range of sizes which does not change significantly when the temperature approaches Tc.

This thesis deals with the scientific achievements of the inspirational scientist Marie Curie Sklodowska as well as with the issue of acute iradiation sickness. Two goals were set in the work. The first objective was to map the life and scientific work of Mrs. Curie. The second objective was to describe the causes and consequences of acute illness from radiation. At the beginning the theoretical part describes the life of Marie Curie Sklodowska. Her difficult beginnings at the University of Paris and her great achievements- discovering the elements of polonium and radium. Further, the work deals with acute radiation sickness together with basics of radiobiology. In the practical part, I tried to find an answer to this question. Why Mrs. Curie did not die from acute radiation sickness? I have gained a lot of information by studying literature, professional articles and internet resources. Most of the facts were obtained from foreign professional journals because there are not many sources in the Czech language. Thanks to this information, I could deal with this person more detailed. At the same time, in the case of toxic polonium-210, an estimated fatal dose for adults was calculated. In addition, calculations were made of how much Marie Curie Sklodowska would have to isolate and incorporate in order to die for the consequences of acute radiation sickness. For better clarity, the results are summarized in the tables. Safety precautions and health problems associated with work with radioactive elements would not be neglected. Marie Curie Sklodowska probably was not able to create a clean polonium, and therefore probably did not even accept this direct contact, which would be able to cause her death.

Neste trabalho foram feitas medidas da impedância complexa dos compostos Heusler Pd2MnSn e Pd2MnSb em função da freqüência, temperatura e campo magnético próximo à temperatura de Curie (Tc). Através de análise computacional dos dados, a magnitude da permeabilidade magnética complexa inicial foi obtida assim como sua dependência com a temperatura, freqüência e campo magnético externo. Ambas as componentes real (μ ') e imaginária (μ ") da permeabilidade magnética apresentam máximos pouco abaixo de Tc. Em baixas freqüências esse efeito é mais pronunciado em Pd2MnSn. Nós atribuímos os altos valores obtidos de μ ' nesse composto a uma alta densidade de paredes de domínio gerada por fronteiras de anti-fase (APBs). A dependência da permeabilidade com a freqüência mostra um comportamento relaxacional. Para o composto Pd2MnSn esse comportamento é bem descrito através da fórmula de Debye modificada comα ~ 0,3. Esse comportamento é característico de um sistema onde domínios magnéticos têm uma distribuição com uma ampla faixa de tamanhos que não muda significativamente quando a temperatura se aproxima de Tc. / In this work measurements of the complex impedance of the Heusler compounds Pd2MnSn and Pd2MnSb were made as a function of frequency, temperature and magnetic field near the Curie temperature (Tc). By computational analysis of the experimental data, the magnitude of the complex initial magnetic permeability was obtained as well as its temperature, frequency and external magnetic field dependencies. Both the real (μ ') and the imaginary (μ ") components of the magnetic permeability show maxima just below Tc. In low frequencies this effect is more pronounced in Pd2MnSn. We attribute the high values of μ ' obtained in this compound to a high density of domain-wall generated by anti-phase boundaries (APBs). The frequency dependence of the permeability shows a relaxational behavior. For the Pd2MnSn compound this behavior is well described by a modified Debye formula with α ~ 0,3. This behavior is characteristic of a system where magnetic domains are distributed within a large range of sizes which does not change significantly when the temperature approaches Tc.

Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2018-06-14T13:15:05Z No. of bitstreams: 2 PDF - Rejane Maria da Silva Farias.pdf: 32571831 bytes, checksum: 52c440efa51e52383e5d5c65e4d8cf16 (MD5) Produto Educacional - Rejane Maria da Silva Farias.pdf: 9841377 bytes, checksum: 56b2db2a9cbcd7711ebdb77a7a790998 (MD5) / Approved for entry into archive by Secta BC (secta.csu.bc@uepb.edu.br) on 2018-06-18T18:12:25Z (GMT) No. of bitstreams: 2 PDF - Rejane Maria da Silva Farias.pdf: 32571831 bytes, checksum: 52c440efa51e52383e5d5c65e4d8cf16 (MD5) Produto Educacional - Rejane Maria da Silva Farias.pdf: 9841377 bytes, checksum: 56b2db2a9cbcd7711ebdb77a7a790998 (MD5) / Made available in DSpace on 2018-06-18T18:12:25Z (GMT). No. of bitstreams: 2 PDF - Rejane Maria da Silva Farias.pdf: 32571831 bytes, checksum: 52c440efa51e52383e5d5c65e4d8cf16 (MD5) Produto Educacional - Rejane Maria da Silva Farias.pdf: 9841377 bytes, checksum: 56b2db2a9cbcd7711ebdb77a7a790998 (MD5) Previous issue date: 2018-04-02 / The objective of this work was to recover the legacy that Marie Curie raised in her scientific and personal life, seeking to highlight the greatest difficulties and perspectives faced by women in the period when they were based, to be part of the sciences in a masculine universe. We do not intend to construct a biography of the scientist, we try to analyze her legacy more vehemently so as to lead us to understand how, despite the difficulties, Marie Curie went beyond socially established limits and became a reference in research with radioactive elements. For this, we chose to approach our problematic through a qualitative research with a historiographic approach, because we understand that, in this way, we will have greater possibilities to understand the emphasis of our objectives and to have a more meaningful answer to what we propose as problematic. We sought to surround ourselves with the most relevant sources of research for the subject, from some originals to secondary sources of good quality and to be faithful to the events of the life of this scientist who lived from 1867 to 1934 (the period we took as a basis for our analysis). We propose a work loyal to the documents researched, without romanticizing or policing the obtained data evidencing a Marie Curie who was not a born genius, nor did she have super abilities that made her the differential in what she intended to accomplish. It is not based on being different with respect to knowing that Marie comes to stand out in the scientific world. She faced the same, or even more, difficulties that any woman faced in this period to be part of the masculinized universe of the sciences. However, we believe that Marie Curie was a woman who took advantage of the opportunities that have arisen in her life, and was able to deal with the difficulties in a way that every obstacle that arises she has turned into the potentiality to achieve its objectives. / Objetivou-se com o presente trabalho, resgatar o legado que Marie Curie ergueu em sua vida científica e pessoal, buscando evidenciar quais as maiores dificuldades e perspectivas que as mulheres enfrentavam, no período tomado como base, para fazer parte das ciências num universo masculinizado. Não pretendemos construir uma biografia da cientista, procuramos analisar com mais veemência o seu legado de modo que nos leve a entender como, apesar das dificuldades, Marie Curie ultrapassou limites estabelecidos socialmente e tornou-se referencia na pesquisa com elementos radioativos. Para isso, optamos por abordar nossa problemática através de uma pesquisa de caráter qualitativo com abordagem historiográfica, por entendermos que, assim, teremos maiores possibilidades de compreender a ênfase dos nossos objetivos e termos uma mais significativa resposta para o que propomos como problemática. Procuramos nos cercar de fontes de pesquisa mais relevantes possível para a temática, desde algumas originais até fontes secundárias de boa qualidade e ser fiel aos acontecimentos da vida dessa cientista que viveu de 1867 a 1934 (período que tomamos como base para a nossa análise). Propomos um trabalho leal aos documentos pesquisados, sem romancear ou policiar os dados obtidos evidenciando uma Marie Curie que não foi um gênio nato, nem detinha super habilidades que fizesse com que ela fosse o diferencial dentro do que pretendia realizar. Não é baseado em ser diferente com relação a saberes que Marie vem se destacar no mundo científico. Ela enfrentou as mesmas, ou até mais dificuldades que qualquer mulher enfrentava nesse período para fazer parte do universo masculinizado das ciências. Contudo, acreditamos que Marie Curie foi uma mulher que aproveitou as oportunidades que surgiram em sua vida, e soube lidar com as dificuldades de uma maneira que cada empecilho que viesse surgir ela transformou em potencialidade para conseguir seus objetivos.

Neste trabalho foram feitas medidas da impedância complexa dos compostos Heusler Pd2MnSn e Pd2MnSb em função da freqüência, temperatura e campo magnético próximo à temperatura de Curie (Tc). Através de análise computacional dos dados, a magnitude da permeabilidade magnética complexa inicial foi obtida assim como sua dependência com a temperatura, freqüência e campo magnético externo. Ambas as componentes real (μ ') e imaginária (μ ") da permeabilidade magnética apresentam máximos pouco abaixo de Tc. Em baixas freqüências esse efeito é mais pronunciado em Pd2MnSn. Nós atribuímos os altos valores obtidos de μ ' nesse composto a uma alta densidade de paredes de domínio gerada por fronteiras de anti-fase (APBs). A dependência da permeabilidade com a freqüência mostra um comportamento relaxacional. Para o composto Pd2MnSn esse comportamento é bem descrito através da fórmula de Debye modificada comα ~ 0,3. Esse comportamento é característico de um sistema onde domínios magnéticos têm uma distribuição com uma ampla faixa de tamanhos que não muda significativamente quando a temperatura se aproxima de Tc. / In this work measurements of the complex impedance of the Heusler compounds Pd2MnSn and Pd2MnSb were made as a function of frequency, temperature and magnetic field near the Curie temperature (Tc). By computational analysis of the experimental data, the magnitude of the complex initial magnetic permeability was obtained as well as its temperature, frequency and external magnetic field dependencies. Both the real (μ ') and the imaginary (μ ") components of the magnetic permeability show maxima just below Tc. In low frequencies this effect is more pronounced in Pd2MnSn. We attribute the high values of μ ' obtained in this compound to a high density of domain-wall generated by anti-phase boundaries (APBs). The frequency dependence of the permeability shows a relaxational behavior. For the Pd2MnSn compound this behavior is well described by a modified Debye formula with α ~ 0,3. This behavior is characteristic of a system where magnetic domains are distributed within a large range of sizes which does not change significantly when the temperature approaches Tc.

While researchers debate the value of psychobiographical research, interest in this area is growing on a national and international basis. Every year, the number of psychobiographical studies at universities in South Africa is growing. Psychobiographical research is qualitative research that utilises psychological theory to explore and describe the lives of extraordinary individuals. The primary aim of this psychobiography was to examine the life of Marie Curie (1867–1934) by employing developmental psychologist and psychoanalyst Erik Erikson’s (1959) theory of psychosocial personality development. Marie Curie was chosen as the research subject because of the researcher’s personal interest and the subject’s prominence as a female scientist. She was a Polish-born and naturalised French scientist who conducted pioneering research on radioactivity. Marie Curie’s ground-breaking discoveries changed the way scientists think about matter and energy and introduced a new era in medical knowledge and the treatment of disease. Her life exemplifies a love of science, commitment, and perseverance. Data were collected from several primary and secondary sources on Marie Curie’s life. The researcher developed a data-collection and analysis matrix to facilitate the systematic collection of data and analysis according to Erikson’s stage theory of psychosocial personality development. This psychobiography suggests that unresolved infantile and early childhood crises gave rise to personality traits that eventually contributed to Curie’s extraordinariness. In the case of Curie, personality traits that are often regarded as atypical or malignant, ironically encouraged perseverance, creativity, and productivity. This study complements the psychobiographical studies done in South Africa on extraordinary individuals. It demonstrated the value of psychobiographical research as a teaching instrument, revealed the usefulness of Erikson’s theory, and illustrated the uniqueness of individuals.

This thesis is a study of tailoring amorphous Fe-B-Si based alloy to produce bulk glassy rods by adding Nb. We have prepared rapid quenched thin ribbons (thickness ~12 µm) by melt spinning, and glassy rods of diameter ~1mm by Cu-mold casting based on compositions (Fe0.78B0.13Si0.9)100-xNbx (x=0, 4, 8, 12), and studied their different physical properties. The melt-spun ribbons are found to be X-ray amorphous, whereas some nano-crystallinity is observed in the case of rods. All the ribbons show high saturation magnetization and low coercivity, which are the desirable characteristics of a soft ferromagnet. These ribbons are thus suitable for designing high frequency transformers, and sensors from an applications point of view. With increasing Nb content their saturation magnetization, ferromagnetic Curie temperature, and resistivity are found to decrease as expected. The temperature dependence of electrical resistivity shows small positive temperature co-efficient that is expected for a metallic disordered material. We have also studied the modification of the properties on thermal annealing the (Fe0.78B0.13Si0.9)96 Nb4 ribbon at different temperatures in a neutral atmosphere.

Cette thèse porte sur l’histoire de l’Église catholique romaine entre la fin du XVIIIe et les premières décennies du XIXe siècle. L’itinéraire du barnabite Francesco Luigi Fontana constitue un prisme pertinent pour éclairer d’un jour nouveau les dynamiques internes à la Curie romaine et les sensibilités des collaborateurs de Fontana, lesquelles permettent aussi d’expliquer les solutions apportées aux nombreuses questions intra- et extraecclésiales soumises à Rome. L’étude des prises de décisions fait apparaître une Curie non monolithique mais au sein de laquelle plusieurs solutions étaient envisagées avant l’adoption de celle définitive.Au-delà même de cette perspective, l’enjeu de la présente recherche est d’ordre méthodologique, s’agissant du type d’analyse à conduire et des catégories à adopter pour comprendre les prises de position intellectuelles, politiques et ecclésiologiques des membres de la Curie. Un autre questionnement a trait à l’exercice, qui fait l’objet de récents approfondissements historiographiques, de la biographie et en l’espèce de la figure d’un cardinal placé à la croisée de plusieurs thématiques majeures de la période considérée, interrogeant enfin certains éléments de continuité de l’histoire de la papauté et du catholicisme de la fin de l’époque moderne au début de la période contemporaine / This doctoral thesis is focused on the history of the Roman Church between the end of the 18th Century and the beginning of the 19th Century. Using Francesco Luigi Fontana’s biography, I will describe the ecclesiastical dynamics and the different sensibilities of the curiali (the members of the Roman Curia) who cooperated with the barnabite to find a solution for both intraecclesiali and extraecclesiali problems submitted to Rome from all over the world.Consequently I will outline the developments in policymaking, in order to represent a non-monolithic Roman Curia, in which –conversely– different solutions were examined before making a definitive political decision.Furthermore this doctoral thesis reflects upon the problems linked to the paradigm chosen and upon the opportunity to use a biography and the category of intransigenza –employed in this study to interpret the intellectual, political and ecclesiological opinions of the curiali– to determine the crucial issues and to identify the elements of continuity of ecclesiastical history.

The alloys FeMnSi and Fe2MnCrSi were obtained in arc furnace in a helium atmosphere at the water-cooled copper ingot mold with the double remelting. Homogenizing annealing of the samples was carried out in a vacuum furnace at 950°C. X-ray analysis was carried out for structure investigation of the alloys. The diffraction patterns were obtained on the X-ray diffractometer Bruker D8 Advance, measurement results were processed using software FullProf v.2.05. Measurement of magnetization isotherms and dependences of the magnetization of alloys on magnetic field were carried out with vibration magnetometer7407 VSM (Lake Shore Cryotronics) in magnetic fields up to 1.7 T at temperature 80 – 400 K. Changes in magnetic part of entropy in various magnetic fields from 0.01 to 1.7 T calculated from isotherms. For sample Fe1.75Mn1.25Si it is shown that at the Curie temperature dependence of the changes of entropy on the magnetic field is almost linear. Obtained dependence of the magnetization on the field at temperatures Tc - 50 K (Tc – the Curie temperature) for all investigated compounds showed that the magnetization of samples decreases with increasing concentration of manganese and chromium. The Curie temperature for alloys Fe3-xMnxSi decreases with increasing of manganese concentration. For alloys Fe2Mn1-xCrxSi the Curie temperature increase with with increasing of chromium concentration. ∆T-effect for all compounds was measured by direct method on an automated installation for measurement of the specific heat and magnetocaloric effect MagEq MMS SV3 (AMT&C) in magnetic field 1.7 T at temperature 85-370 К. The magnitude of the magnetocaloric effect of the investigated compounds kept constant in the investigated manganese and chromium concentration range including at room temperature. / В дуговой печи были получены сплавы FeMnSi и Fe2MnCrSi в атмосфере гелия на водоохлаждаемой медной изложнице с двухкратной переплавкой. Гомогенизирующий отжиг образцов проводился в вакуумной печи при температуре 950°С. Для исследования структуры всех сплавов был проведен рентгеноструктурный анализ. Дифрактограммы были получены на рентгеновском дифрактометре Bruker D8 Advance, результаты измерения были обработаны с использованием программного обеспечения FullProf v.2.05. На вибрационном магнитометре 7407 VSM (Lake Shore Cryotronics) в магнитных полях до 1.7 Тл в температурном интервале от 80 до 400 K проведены измерения изотерм намагниченности и измерена зависимость намагниченности сплавов от магнитного поля. Рассчитано по изотермам изменение магнитной части энтропии в различных полях от 0.01 до 1.7 Тл. Для образца Fe1.75Mn1.25Si показано, что при температуре Кюри зависимость изменения энтропии от величины поля почти линейна. Полученные зависимости намагниченности от поля при температурах Tc – 50 К (Tc – температура Кюри) для всех исследуемых соединений показали, что намагниченность образцов уменьшается при увеличении концентрации марганца и хрома. Температура Кюри сплавов Fe3-xMnxSi уменьшается с ростом концентрации марганца. При увеличении концентрации хрома в соединении Fe2Mn1-xCrxSi температура Кюри растет. На автоматизированной установке для измерения магнитокалорического эффекта и теплоемкости MagEq MMS SV3 (AMT&C) измерен прямым методом ∆T-эффект всех соединений в магнитном поле 1.7 Тл в диапазоне температур 85-370 К. Величина магнитокалорического эффекта изученных соединений сохраняется неизменной в исследованном диапазоне концентраций марганца и хрома в том числе и при комнатной температуре.