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S?ntese e caracteriza??o de ferritas de n?quel dopadas com cobalto e efeito da substitui??o nas suas propriedades magn?ticasRodrigues, ?dila Priscilla Gomes 11 December 2014 (has links)
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Previous issue date: 2014-12-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The ferrite composition Ni1 - xCoxFe2O4 (0 ≤ x ≤ 0.75) were obtained by the method of
microwave assisted synthesis and had their structural and magnetic properties evaluated due
to the effect of the substitution of Ni by Co. The compounds were prepared: according to the
concept of chemical propellants and heated in the microwave oven with power 7000kw. The
synthesized material was characterized by absorption spectroscopy in the infrared (FTIR), Xray
diffraction (XRD) using the Rietveld refinement, specific surface area (BET) , scanning
electron microscopy (SEM) with aid of energy dispersive analysis (EDS) and magnetic
measurements (MAV). The results obtained from these techniques confirmed the feasibility
of the method of synthesis employed to obtain the desired spinel structure, the ferrite, nickel
ferrite as for nickel doped with cobalt. The results from XRD refinement ally showed the
formation of secondary phases concerning stages α - Fe2O3, FeO, (FeCo)O e Ni0. On the other
hand, there is an increase in crystallite size with the increase of cobalt in systems, resulting in
an increased crystallinity. The results showed that the BET systems showed a reduction in
specific surface area with the increase of cobalt and from the SEM, the formation of irregular
porous blocks and that the concentration of cobalt decreased the agglomerative state of the
system. The magnetic ferrites studied showed different characteristics according to the
amount of dopant used, ranging from a very soft magnetic material (easy magnetization and
demagnetization ) - for the system without cobalt - a magnetic material with a little stiffer
behavior - for systems containing cobalt. The values of the coercive field increased with the
increasing growth of cobalt, and the values of saturation magnetization and remanence
increased up to x = 0,25 and then reduced. The different magnetic characteristics presented by
the systems according to the amount of dopant used, allows the use of these materials as
intermediates magnetic / As ferritas de composi??o Ni1−xCoxFe2O4 (0≤x≤0,75) foram obtidas atrav?s do m?todo
de s?ntese assistida por microondas e tiveram suas propriedades estruturais e magn?ticas
avaliadas em fun??o do efeito da substitui??o do Ni pelo Co. Os compostos foram preparados
de acordo com o conceito da qu?mica dos propelentes e aquecidos em forno micro-ondas com
pot?ncia 7000kw. O material sintetizado foi caracterizado por espectroscopia de absor??o na
regi?o do infravermelho (FTIR), difra??o de raios X (DRX), com o uso do refinamento pelo
m?todo de Rietveld, ?rea superficial espec?fica (BET), microscopia eletr?nica de varredura
(MEV) com aux?lio de an?lise por dispers?o de energia (EDS) e medidas magn?ticas (MAV).
Os resultados obtidos, a partir destas t?cnicas confirmaram a viabilidade do m?todo de s?ntese
empregado para a obten??o da estrutura espin?lio desejada, tanto para a ferrita de n?quel
quanto para as ferritas de n?quel dopadas com cobalto. Os resultados do DRX, aliado ao
refinamento, mostraram a forma??o de fases secund?rias tais como as fases α - Fe2O3, FeO,
(FeCo)O e Ni0. Por outro lado, observou-se um aumento no tamanho do cristalito com o
incremento do cobalto nos sistemas, implicando em um aumento da cristalinidade. Os
resultados do BET mostraram que os sistemas apresentaram uma redu??o da ?rea superficial
espec?fica com o incremento do cobalto e a partir do MEV observou-se a forma??o de blocos
porosos irregulares e que o aumento da concentra??o de cobalto dimunuiu o estado de
aglomera??o dos sistemas. As ferritas estudadas apresentaram caracter?sticas magn?ticas
diferenciadas de acordo com a quantidade do dopante utilizado, variando de um material
magn?tico bastante mole (f?cil magnetiza??o e desmagnetiza??o) - para o sistema sem
cobalto - a um material magn?tico com comportamento um pouco mais duro - para os
sistemas contendo cobalto. Os valores do campo coercitivo aumentaram com o crescente
incremento do cobalto, e os valores de magnetiza??o de satura??o e reman?ncia aumentaram
at? x=0,25 e depois reduziram. As caracter?sticas magn?ticas diferenciadas apresentadas pelos
sistemas, de acordo com a quantidade de dopante utilizado, permite o uso desses materiais
como magn?ticos intermedi?rios
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S?ntese, caracteriza??o de ferritas espin?lio com propriedades magn?ticas e absorvedoras de microondasSilva, Jos? Eves Mendes da 08 March 2013 (has links)
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Previous issue date: 2013-03-08 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Were synthesized spinel-type ferrites with general formula Ni0,8Mg0.2-xMxFe2O4,
where M represents the doping Mn, Co or Mn + Co simultaneously, x ranges for the values
0.02, 0.05 and 0.1. The value of x was divided by 2 in cases where M equals Mn and Co
conjugates. We used the citrate precursor method and heat treatment to obtain the phases at
1100?C. The materials were characterized by XRD, TGA/ DTGA, SEM, MAV and
reflectivity measurements by the method of waveguide. Powders to 350?C/3.5 h were
crystalline and nanosized. According to the results this temperature all powders have a
percentage of ferrite phase over 90%. The composition had the addition of Mn and Co
simultaneously showed a higher percentage of secondary phase NiO, 5.8%. The TGA/DTGA
curves indicate that this sample reached phase (s) crystalline (s) at lowest temperatures. The
X-ray diffractograms of the samples calcined at 350?C and 1100?C were treated with the
Rietveld refinament technique. The powders calcined at 1100 ?C/3h in air show to be 100%
except spinel phase composition with 0.02 doping. The micrographs show clusters of particles
with sizes smaller than 1 μm in calcination temperature of 1100?C which agreed with the
result of Rietveld refinement. In the compositions doped with Mn were higher values of
magnetization (45.90 and 53.20 Am2/kg), which did not cause high microwave absorption.
The theoretical calculation of magnetization (MT) was consistent with the results, considering
that there was agreement between the increase of magnetization experimental and theoretical.
It was observed that there was the interrelation of the final effect of absorption with the
thickness of MARE, the composition of ferrimagnetic materials and in particular the specific
values of frequency. The analysis shows that the reflectivity increases in the concentration of
cobalt increased the frequency range and also for absorption 10.17 GHz and 84%,
respectively. The best result of chemical homogeneity and the value of 2.96 x 10-2 tesla
coercive field were crucial for high performance ferrite absorber with 0.1 cobalt. The Cobalt
has high magnetocrystalline anisotropy, it is associated with an increased coercive field, Hc.
Therefore, this property improves the results of reflectivity of spinel ferrites / Foram sintetizadas ferritas do tipo espin?lio com f?rmula geral Ni0,8Mg0,2-xMxFe2O4,
onde M representa os dopantes Mn, Co ou Mn + Co simultaneamente, x varia para os valores
0,02; 0,05 e 0,1. O valor de x foi dividido por 2 nos casos em que M equivale a Mn com Co
conjugados. Foi utilizado o m?todo dos citratos precursores e tratamento t?rmico na obten??o
das fases a 1100?C. Os materiais foram caracterizados por DRX, TGA/DTGA, MEV, MAV e
medidas de refletividade pelo m?todo de guia de ondas. Os p?s a 350?C/3,5h foram cristalinos
e nanom?tricos. De acordo com os resultados nesta temperatura todos os p?s apresentam um
percentual de fase ferrita superior a 90%. A composi??o que teve a adi??o de Mn e Co
simultaneamente apresentou maior percentual de fase secund?ria NiO, 5,8%. As curvas
TGA/DTGA indicam que essa amostra alcan?ou fase(s) cristalina(s) em temperaturas mais
baixas. Os difratogramas de raios X das amostras calcinadas a 350?C e 1100?C foram tratados
pela t?cnica de refinamento Rietveld. Os p?s calcinados a 1100?C/3h em atmosfera ambiente
mostram ser 100% de fase espin?lio exceto a composi??o com 0,02 de dopantes. As
micrografias apresentam aglomerados de part?culas com tamanhos menores que 1 μm na
temperatura de calcina??o de 1100?C, o que concordou com o resultado de refinamento
Rietveld. Nas composi??es dopadas com Mn ocorreram os maiores valores de magnetiza??o
(45,90 e 53,20 Am2/kg), o que n?o acarretou alta absor??o de microondas. O c?lculo te?rico
da magnetiza??o (MT) foi coerente com os resultados, considerando-se que houve
concord?ncia entre o aumento das magnetiza??es experimental e te?rica. Observa-se que
houve interrela??o do efeito final de absor??o com a espessura do MARE, a composi??o do
material ferrimagn?tico em particular e os valores espec?ficos de freq??ncia. A an?lise de
refletividade indica que o aumento na concentra??o de cobalto aumentou a faixa de freq??ncia
e a absor??o para 10,17 GHz e 84%, respectivamente. O resultado indica que a melhor
homogeneidade qu?mica e o valor 2,96 x 10-2 tesla de campo coercitivo foram determinantes
para o alto desempenho absorvedor da ferrita com 0,1 de cobalto. O Cobalto tem alta
anisotropia magnetocristalina, isto est? associado ao aumento do campo coercitivo, Hc.
Portanto, essa propriedade melhora os resultados de refletividade das ferritas espin?lio
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Crescimento e esporula??o de Stemphylium sp. sob diferentes meios de cultura e condi??es de ambiente / Growth and sporulation of Stemphylium sp. under different culture media and environment conditionsSOUZA, Fernanda Corr?a de 08 October 2015 (has links)
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Previous issue date: 2015-10-08 / CAPES / CNPq / FAPERJ / The tomato crop is subject to attack by diseases of different etiologies, especially the gray leaf spot, caused by Stemphylium sp., which infects the aerial part of the plant and has shown higher incidences and losses in growing areas in recent years. Despite the disease importance, few studies are developed to elucidate the aspects of epidemiology and control of the disease. The use of trials involving pathogen inoculations is essential for carrying out these studies, which requires efficient methods of in vitro multiplication. The aim of this study was to verify the influence of some factors applied during incubation on the mycelial growth and sporulation of the pathogen under controlled conditions. Different culture media (V8 juice agar, tomato juice, PDA, oat, carrot, corn flour, tomato leaf and V8+PDA), temperature (25?C; 25+10?C; 25+15?C; 25+20?C; 25/10?C; 25/15?C; 25/20?C), photoperiods (day/night, respectively, of 0h/24h, 4h/20, 6h/18h, 8h/16h and 12h/12h), luminosity (cool white lamps and black light lamps) and stress types applied to the colony (scratching and UV) were tested. Promising factors were determinate and, after this, the virulence of conidia obtained on the selected system was evaluated. Results indicated the tomato juice and V8 juice agar more favorable for growth and sporulation, respectively. The temperature of 25?C continuous favored mycelial growth and alternation of 25?C (day) and 10?C (night) the sporulation. The growth was more stimulated by 12h light/ 12h dark of photoperiod and the sporulation was higher 6h light/ 18h dark. The different light sources had influence on sporulation and cool white lamps were the most stimulating. Not stressed colonies had better results in conidia production. Thus, the suggested protocol in this study consisted in incubation in V8 juice agar media, alternately temperature of 25?C (day) and 10?C (night), 12h light / 12 h dark photoperiod. The produced conidia in this methodology showed great capacity of infection on tomato plants. / A cultura do tomate est? sujeita ao ataque de doen?as de diferentes etiologias, com destaque para a mancha-de-estenf?lio, causada por Stemphylium sp., que infecta a parte a?rea da planta e tem apresentado maiores incid?ncias e perdas nas ?reas de cultivo nos ?ltimos anos. Apesar da import?ncia desta doen?a, s?o poucos os estudos realizados visando esclarecer aspectos da epidemiologia e controle da doen?a. Para realiza??o desses trabalhos ? fundamental o uso de ensaios que envolvam inocula??es do pat?geno o que requer m?todos eficientes de sua multiplica??o in vitro. O presente trabalho teve o objetivo de avaliar a influ?ncia de alguns fatores sobre o crescimento micelial e esporula??o do pat?geno em condi??es controladas. Diferentes meios de cultura (V8, suco de tomate, BDA, aveia, cenoura, farinha de milho, folha de tomate e V8+BDA), temperatura (25 ?C, 25+10 ?C, 25+15 ?C, 25+20 ?C, 25/10 ?C, 25/15 ?C; 25/20 ?C), fotoper?odo (luz/escuro respectivamente, 0h/24h, 4h/20h, 6h/18h, 8h/16h e 12/12h), luminosidade (l?mpadas brancas frias e l?mpadas de luz negra) e tipos de estresse aplicado ? col?nia (raspagem e comprimento de onda) foram testados. Ap?s a determina??o das melhores combina??es de temperatura, fonte de luz e fotoper?odo avaliou-se a virul?ncia dos con?dios obtidos no sistema selecionado. Os resultados indicaram o meio suco de tomate e V8 como os mais favor?veis ao crescimento e esporula??o respectivamente. A temperatura de 25 ?C cont?nuos favoreceu o crescimento micelial e a altern?ncia de 25 ?C (diurno) e 10 ?C (noturno) a esporula??o. O fotoper?odo 12h luz/12h escuro foi o que mais estimulou o crescimento, j? para esporula??o o estimulo foi maior quando foi oferecido 6h luz/18h escuro. As diferentes fontes de luz utilizadas tiveram influ?ncia marcante na esporula??o, sendo as l?mpadas brancas frias as mais estimulantes. As col?nias que n?o sofreram estresse obtiveram melhores resultados na produ??o de con?dios. Dessa forma, o protocolo sugerido neste trabalho consistiu de inocula??o em meio V8, temperatura alternada de 25 ?C (diurno) e 10 ?C (noturno), fotoper?odo de 6 horas de luz branca/18 horas de escuro. Os con?dios produzidos nesta metodologia apresentam grande capacidade de infec??o de plantas de tomateiro.
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Estudo de caso das iniciativas socioambientais para a gest?o sustent?vel empresarial / Study of environmental initiatives for sustainable management in businessMOURA, Jadiel Guerra de 29 October 2013 (has links)
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Previous issue date: 2013-10-29 / This is a study of the known principles of sustainable management in business environment with social and environmental initiatives, with TV GLOBO?s example. The sustainable potential, pioneering initiatives such as ISO 14001 certification and performance in waste management are covered under the studied models and compared in relation to official standards for sustainability. The bibliographic source which gives the theoretical foundation portfolio primarily comprises the sustainable value of Hart and the main instruments for the sustainable management such as ISO 16000, 26000 standards, reports the GRI indicators and the ISE . The environmental initiatives of the company and the results of performance and environmental care were extracted from published social reports, presentations at conferences, seminars, videos and materials available in various media. Additionally, a questionnaire of commitments to sustainability, interviews and content of programs complement the disclosed data and environmental issues. As a result, we have a evaluation of the range of initiatives, a diagnosis of the potential for creating sustainable value and a comparative analysis of sustainable actions in relation to systems and studied models. / Este trabalho ? um estudo dos princ?pios conhecidos da gest?o sustent?vel no ?mbito empresarial tendo como exemplo as iniciativas socioambientais da TV GLOBO. O potencial sustent?vel, iniciativas como o pioneirismo na certifica??o ISO 14001 e o desempenho na gest?o de res?duos s?o contemplados segundo modelos estudados e comparados em rela??o a par?metros oficiais de sustentabilidade. A fonte bibliogr?fica que d? a fundamenta??o te?rica compreende basicamente o portf?lio de valor sustent?vel de Hart e os principais instrumentos para a gest?o sustent?vel como as normas ISO 16000, 26000, relat?rios do GRI e indicadores do ISE. As iniciativas socioambientais da empresa, bem como os resultados de desempenho e de cuidados ambientais, foram extra?das de balan?os sociais publicados, apresenta??es feitas em congressos, semin?rios, v?deos e materiais disponibilizados em diversas m?dias. Adicionalmente, um question?rio de compromissos com a sustentabilidade, entrevistas realizadas e conte?dos de programas divulgados complementam os dados e os temas socioambientais abordados. Como resultado, temos uma avalia??o do conjunto de iniciativas, diagn?stico do potencial de cria??o de valor sustent?vel e an?lise comparativa de a??es sustent?veis em rela??o aos sistemas e modelos estudados.
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Estudo do c?tion org?nico 2-etil-1,3,4-trimetilimidaz?lio na s?ntese de ze?litas e ze?tiposMelguizo, Paloma Vinaches 27 October 2017 (has links)
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Previous issue date: 2017-10-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Nesta tese de doutorado estudou-se o agente direcionador de estrutura 2-etil-1,3,4-
trimetilimidaz?lio no contexto da s?ntese de ze?litas e ze?tipos em meio fluoreto.
Inicialmente, foi realizado um estudo aprofundado da ze?lita pura silica HPM-1 para o
entendimento do papel do c?tion na nuclea??o e crescimento zeol?tico, conseguindo explicar a
forma??o dos canais helicoidais e a ordem de apari??o das unidades secund?rias de
constru??o. Subsequentemente, foi empregada uma metodologia de introdu??o de
hetero?tomos em HPM-1 para proporcionar propriedades catal?ticas a esta, nunca tendo sido
empregada o presente m?todo nesta topologia zeol?tica anteriormente. Como resultado,
obtiveram-se tr?s materiais Al-HPM-1 diferentes, que foram caracterizados e testados na
rea??o de dehidrata??o de etanol. Finalmente, foi realizado um estudo explorat?rio do c?tion
org?nico em s?ntese de ze?tipos (com Si, Al e P), resultando em duas fases SAPO: os ze?tipos
CHA e LTA. Foi comprovado que a estrutura SAPO-CHA foi direcionada n?o somente pelo
emprego do composto org?nico e do meio fluoreto, mas sua obten??o foi devida ? temperatura
e a uma combina??o de dilui??o e tempo. No caso do SAPO-LTA, o efeito direcionador foi
consequ?ncia majoritariamente pelo emprego do c?tion org?nico. / In this doctoral thesis the structure-directing agent 2-ethyl-1,3,4-trimethylimidazolium was
studied in the context of zeolite and zeotype synthesis in hydrofluoric media. Initially, it was
deepened into the study of the pure silica zeolite HPM-1 to understand the role of the cation in
the nucleation and growth, explaining the helical channels and the order of secondary building
units formation. Subsequently, an alternative methodology of heteroatom introduction, never
reported for the present material, was also presented to give HPM-1 catalytic properties. As a
result of it, three different Al-HPM-1 samples were obtained, characterized and tested in
ethanol dehydration reaction. Finally, an exploratory study of the organic cation in zeotype
synthesis (with Si, Al and P) was performed, giving two main SAPO phases: CHA and LTA
zeotypes. It was proven that the SAPO-CHA structure was directed not only by the use of the
organic cation and the hydrofluoric media, but also its obtention was influenced by the
temperature and a combination of dilution and time. In the case of the SAPO-LTA, the
directing effect was mainly due to the organic cation.
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S?ntese e caracteriza??o de ?xidos de c?rio e cobalto obtidos por gel-combust?o e Pechini aplicados ?s rea??es de oxida??o de n-hexanoSales, Luciano Leal de Morais 29 April 2008 (has links)
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Previous issue date: 2008-04-29 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Oxide type spinel AB2O4 presents structure adjusted for application in the automobile industry. The spinel of cobalt has many practical applications had its excellent physical and chemical properties such as catalyst in hydrocarbon oxidation reaction. The CeO2 has been used in many of these processes because it assigns to a material with excellent thermal resistance and mechanics, high capacity of oxygen stockage (OSC) among others properties.
This work deals with the synthesis, characterization and catalytic application of spinel of cobalt and CeO2 with fluorita structure, obtained for method of Pechini
and method of Gel-Combustion. The process of Pechini, the puff was obtained at 300 ?C for 2 h in air. In the process of Gel-Combustion the approximately at 350 ?C material was prepared and burnt for Pyrolysis, both had been calcined at 500 ?C, 700 ?C, 900 ?C and 1050 ?C for 2 h in air. The materials of the calcinations had been characterized by TG/DTA, electronic microscopy of sweepings (MEV), spectroscopy of absorption in the infra-red ray (FTIR) and diffraction of X-rays (DRX). The obtained material reaches the phase oxide at 450 oC for Pechini method and 500 ?C for combustion method. The samples were submitted catalytic reaction of n-hexane on superficies of materials. The reactor function in molar ration of 0, 85 mol.h-1.g-1 and temperature of system was 450 ?C. The sample obtained for Pechini and support in alumine of superficial area of 178,63 m2.g-1 calcined at 700 ?C, give results of catalytic conversions of 39 % and the sample obtained for method of gel-combustion and support in alumina of 150 mesh calcined at 500 ?C result 13 % of conversion. Both method were selective specie C1 / O espin?lio de cobalto tem muitas aplica??es pr?ticas devido as suas excelentes propriedades f?sicas e qu?micas tal como catalisador nas rea??es de oxida??o de hidrocarboneto. O CeO2 tem sido utilizado em muitos processos porque designa um material com excelente resist?ncia t?rmica e mec?nica, alta capacidade de estocagem de oxig?nio (OSC) entre outras propriedades. Este trabalho trata da s?ntese e caracteriza??o e aplica??o catal?tica dos ?xidos de cobalto com estrutura espin?lio e CeO2 com estrutura fluorita, obtidos pelo
m?todo de Pechini e pelo m?todo de gel-combust?o. No processo Pechini o puff foi obtido a 300 ?C por 2 h em atmosfera ambiente. No processo de gel-combust?o o material foi preparado e queimado a aproximadamente 350 ?C por igni??o espont?nea e, posteriormente, ambos os p?s foram calcinados a 500 ?C, 700 ?C, 900 ?C e 1050 ?C por 2 h em atmosfera ambiente. Os p?s-resultantes das calcina??es foram caracterizados por TG/DTA, microscopia eletr?nica de varredura (MEV), espectroscopia de absor??o no infravermelho (FTIR) e difra??o de raios X (DRX). O material obtido deve atingir a fase ?xida
a 450 ?C, para Pechini e 500 ?C para gel-combust?o. As amostras foram submetidas a rea??es catal?ticas de n-hexano sobre os catalisadores de Ce/Co. O reator operou a uma raz?o F/W fluxo molar de reagente por grama de catalisador de 0,85 mol.h-1.g-1 e temperatura no leito de 450 ?C. Para amostras obtidas por Pechini calcinadas a 700 ?C e suportada em alumina com
?rea superficial de 178,63 m2.g-1 obteve-se 39 % de convers?o catal?tica. Para as amostras obtidas pelo m?todo de gel-combust?o calcinadas a 500 ?C e
suportada em alumina da Porogel com 150 mesh obteve cerca de 13 % de convers?o catal?tica. Ambos os m?todos foram seletivos a esp?cie C1.
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Valida??o de conte?do do instrumento para consulta de enfermagem na visita domiciliar ?s pessoas com les?o medular: um enfoque no autocuidado / Content validation of instrument for consultation in nursing home visits to people with spinal cord injury: a focus on self-careCoura, Alexsandro Silva 06 February 2013 (has links)
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Previous issue date: 2013-02-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This study aimed to validate the contents of an Instrument for Nursing Consultation in the Home Visit of people with Spinal Cord Injury (INCEVDOP-LM), based on the Self-Care Deficit Theory. The methodological development study was conducted with spinal cord injured (SCI) people ascribed in the Family Health Units the city of Natal/RN/Brazil, and with the nurses of these institutions. The study was conducted from Januray 2012 to January 2013 in two phases: the first aimed to identify the need for self-care of persons with SCI, and the second to develop and validate the INCEVDOP-LM. The first phase consisted of a census study of people with SCI living in Natal/RN. In the second phase, a non-probabilistic convencience sample of subjects was selected to form two groups: First stage - Group 1 of the first stage was comprised by 73 adults with SCI diagnosed with paraplegia or tetraplegia, with cognitive function preserved and that were registered to some family health unit; Group 2 of the Second phase was composed of six experts that were nurses with doctoral formation, scientific experience in the area of technology development or assistance to persons with SCI, and with publications in periodicals Qualis A2. Data collection of the first phase was conducted through home visits of people with SCI that responded three instruments: Questionnaire I (comprised of demographic and socioeconomic variables), The Competency Rating Scale for Self-care (ASA) and the Barthel Index (an instrument for evaluation of functional capacity). The research for the second phase was conducted in two stages: I-construction of the INCEVDOP LM; II-validation of the INCEVDOP-LM. The instrument and an evaluation form were forwarded to the experts for the validation. The correlations between the responses were analyzed by the Kappa test, with accepting values of>0.75. The evaluation criteria were: organization, clarity, simplicity, readability, appropriateness of vocabulary, objectivity, accuracy, reliability and suitability and the positive responses with frequency values of≥90% were considered excellent. The chi-square test was used to investigate the differences between proportions. The study attended to the principles of Human Rights CNS Resolution 196/96. Results were reported by means of four articles derived from the study. The findings indicate that the items that showed disagreement among experts (k=0.02) were diagnoses, interventions and evaluation of the nursing features pertaining to the domains of Nutrition, Hygiene, Elimination, Physical, Social and Psychological, and of the Ability to perform work activities feature. Agreement among the experts were reported for the other items, with kappa ranging from 0.72 to 1. After removing items with disagreement, all criteria achieved excellent rates and no significant differences were observed between the proportions of responses of evaluation of experts (p>0.05). We conclude that the instrument shows validity to serve as a guide for nurses to conduct a systematic consultation during the home visit to people with spinal cord injury, with emphasis on self-care. The instrument must go through other levels of validation when applied in the clinical setting / Objetivou-se validar o conte?do de um Instrumento para Consulta de Enfermagem na Visita Domiciliar ?s Pessoas com Les?o Medular (INCEVDOP-LM), baseado no modelo conceitual da Teoria do D?ficit de Autocuidado. Estudo de desenvolvimento metodol?gico, realizado com as pessoas com LM adscritas nas Unidades de Sa?de da Fam?lia (USF) de Natal e com os enfermeiros dessas institui??es, no per?odo de janeiro de 2012 a janeiro 2013. O estudo foi desenvolvido em duas fases: a primeira para identificar as necessidades de autocuidado das pessoas com LM, e a segunda para desenvolver e validar o INCEVDOP-LM. Na primeira fase foi realizado o censo de pessoas com LM residentes em Natal/RN. Na segunda fase a amostragem foi n?o-probabil?stica por conveni?ncia. Foram formados dois grupos: Primeira fase - G1: 73 pessoas com LM diagnosticadas por especialista, com paraplegia ou tetraplegia, adultas, fun??o cognitiva preservada e adscritas a alguma USF; Segunda fase - G2: seis juizes enfermeiros, com titula??o de doutor, produ??o cient?fica na ?rea de desenvolvimento de tecnologias ou assist?ncia ?s pessoas com LM e publica??o com qualis A2. Para coleta de dados, na primeira fase, foram realizadas visitas domiciliares as pessoas com LM e aplicados tr?s instrumentos: Question?rio I (vari?veis demogr?ficas e socioecon?micas), Escala de Avalia??o da Compet?ncia para o Autocuidado (ASA) e ?ndice de Barthel (avalia??o da capacidade funcional). Na segunda fase, a pesquisa foi desenvolvida em duas etapas: I. Constru??o do INCEVDOP-LM; II. Valida??o do INCEVDOP-LM. O instrumento foi encaminhado, juntamente com um formul?rio de avalia??o, para aprecia??o dos especialistas, sendo a concord?ncia entre eles analisada por meio do teste Kappa, aceitando-se valores >0,75. Os crit?rios avaliados foram: organiza??o, clareza, simplicidade, facilidade de leitura, adequa??o do vocabul?rio, objetividade, precis?o, credibilidade e adequa??o. Considerou-se como frequ?ncia excelente de respostas positivas valores ≥90%. Utilizou-se o teste Qui-quadrado para investigar as diferen?as entre as propor??es observadas. Foram considerados os princ?pios da Resolu??o 196/96. Os resultados foram apresentados por meio de 4 artigos cient?ficos derivados da pesquisa. Verificou-se que os itens diagn?sticos, interven??es e avalia??o de enfermagem das facetas dos dom?nios Nutri??o, Higiene, Elimina??o, F?sico, Social e Psicol?gico e a faceta Capacidade para realizar atividades laborais apresentaram discord?ncia entre os especialistas (k=0,02). Nos demais itens ocorreu concord?ncia, com kappa variando de 0,72 a 1. Ap?s a supress?o dos itens com discord?ncia entre os especialistas, todos os crit?rios atingiram ?ndices excelentes e n?o ocorreram diferen?as significativas entre as propor??es das respostas da avalia??o dos especialistas (p>0,05). Conclui-se que o instrumento apresenta validade para servir como guia para os enfermeiros na realiza?ao da consulta sistematizada de enfermagem na visita domiciliar ?s pessoas com les?o medular, com enfoque no autocuidado, devendo passar por outros n?veis de valida??o quando aplicado no ?mbito cl?nico
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Novas fronteiras petrol?feras no Brasil : uma an?lise da necessidade de nova regulamenta??o da ?rea do pr?-sal sob a ?tica constitucionalFontes, Grazielly dos Anjos 06 September 2010 (has links)
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Previous issue date: 2010-09-06 / The Oil industry in Brazil has gone through several stages during the economical, political and social historical process. However, the significative changes have happened in the last fifteen years, due to market opening arising from the relaxation of the state monopoly over the Oil deposits and its derivatives. The edition of the Constitutional Amendment #9, changing the first paragraph of the 177th item of the Federal Constitution, marked the end of a stiffness about the monopoly that the Brazilian state kept in relation to the exploration and research of Oil and Gas. The economical order was fundamental to actualize the idea contained in the #9 Amendment, since its contents has the power to set up measures to be adopted by public power in order to organize the economical relations from a social viewpoint. The new brazilian Oil scenery, called pre-salt, presents itself in a way to amaze the economical markets, in addition to creating a new perspective to the social sector. This work will identify, in this new scenario, the need for change in the legal system. Nevertheless, this subject must not be treated in a thoughtless way: being an exhaustible good, we shall not forget that the future generations also must benefit from the exploration of natural resources recently discovered. The settlement of a new regulatory mark, including the change in the concession contract model to production and sharing is one of the suggested solutions as a bill in the National Congress, in an attempt to ensure the sovereignty of the nation. The constitutionality of a new regulatory mark is questioned, starting from an analysis of the state monopoly, grounding the comprehnsions in the brazilian constitutions, the relevance of the creation of Petrobras for self-assertion of the state about the monopoly of Oil and derivatives, and its posture after the Constitutional Amendment n? 9 (1995), when a company stops having control of the state monopoly, beginning to compete in a fairly way with other companies. The market opening and private initiative are emphasized from the viewpoint of the Constitutional Principles of the Economical and Social Order. The relaxation of the monopoly regarding the exploratory activity in the Federal Constitution doesn't deprive from the Union the ownerships of underground goods, enabling to this federal entity to contract, directly or by concession of exploration of goods, to state-owned or private companies. The existing oil in the pre-salt layer transforms the scenario from very high risk to low risk, which gives the Union the possibility of defining another way of exploring this resources in the best interests of the Public Administration / A ind?stria do petr?leo no Brasil passou por v?rias etapas durante o processo hist?rico econ?mico, pol?tico e social. Todavia, suas significativas mudan?as ocorreram nos ?ltimos quinze anos, atrav?s da abertura do mercado decorrente da flexibiliza??o do monop?lio estatal sobre as jazidas de petr?leo e seus derivados. A edi??o da Emenda Constitucional n? 9, alterando o par?grafo 1?, do art. 177 da Constitui??o Federal, caracterizou o fim de uma rigidez quanto ao monop?lio que o Estado brasileiro mantinha em rela??o ? pesquisa e explora??o de petr?leo e g?s. A ordem econ?mica foi fundamental para efetivar a id?ia contida na Emenda n? 9, visto que seu conte?do tem o cond?o de estabelecer medidas a serem adotadas pelo poder p?blico a fim de organizar as rela??es econ?micas, sob o vi?s social. O novo cen?rio petrol?fero brasileiro, denominado pr?-sal, apresenta-se de forma a surpreender os mercados econ?micos, al?m de criar uma nova perspectiva para o setor social. O presente trabalho identificar? no novo cen?rio a necessidade de mudan?a do regime jur?dico, todavia, esse assunto n?o pode ser tratado de forma imediatista: como se trata de um bem esgot?vel n?o se deve esquecer que as gera??es futuras tamb?m precisam beneficiar-se da explora??o dos recursos naturais rec?m-descobertos. O estabelecimento de um novo marco regulat?rio, incluindo a mudan?a do modelo de contrato concess?o para produ??o e partilha ? uma das solu??es propostas a n?vel de projeto de lei no Congresso Nacional na tentativa de garantir a soberania da na??o. Questiona-se a constitucionalidade de um novo marco regulat?rio, partindo-se da an?lise do monop?lio estatal, resgatando a compreens?o nas constitui??es brasileiras, a relev?ncia da cria??o da Petrobras para auto-afirma??o do Estado quanto ao monop?lio de petr?leo e derivados, e sua postura ap?s a Emenda Constitucional n? 9 de 1995 quando a empresa deixa de ter o controle do monop?lio estatal, passando a concorrer de forma igualit?ria com outras empresas. Ressalva-se a abertura do mercado e a iniciativa privada sob ?tica dos Princ?pios Constitucionais da Ordem Econ?mica e Social. A flexibiliza??o do monop?lio quanto a atividade explorat?ria na Constitui??o Federal n?o retira da Uni?o a propriedade dos bens do subsolo, possibilitando a este ente federal a contrata??o direta ou atrav?s de concess?o da explora??o do bem a empresas estatais ou privada. O petr?leo existente na camada pr?-sal, transforma um cen?rio de alt?ssimo risco em baixo risco, o que confere a Uni?o a possibilidade de determina??o de outra forma de explorar esses recursos de forma a fazer vale os interesses prim?rio da Administra??o P?blica
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LCD-OpenPACS: sistema integrado de telerradiologia com aux?lio ao diagn?stico de n?dulos pulmonares em exames de tomografia computadorizadaFirmino Filho, Jos? Mac?do 04 December 2015 (has links)
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Previous issue date: 2015-12-04 / O c?ncer de pulm?o ? uma das principais causas de morte no mundo. A sua alta taxa de mortalidade est? relacionada com detec??o da patologia em est?gios avan?ados. De acordo com a literatura, a tomografia computadorizada (TC) ? a modalidade de imagem mais indicada para a detec??o precoce de n?dulos pulmonares. No entanto, ela impacta diretamente na carga de trabalho dos radiologistas. Pesquisadores propuseram v?rios sistemas automatizados para auxiliar os radiologistas na detec??o do c?ncer de pulm?o. Entretanto, a utiliza??o desses sistemas necessitava de altera??es no fluxo de trabalho cl?nico e altos custos de implanta??o. Visando solucionar estas barreiras, o presente trabalho prop?e uma nova abordagem para detec??o de n?dulos pulmonares, em exames de tomografia computadorizada (TC), baseado no descritor Histograma do Gradiente Orientada (HoG) e M?quina de Vetor de Suporte (SVM). Al?m disso, ? proposto uma aplica??o desta abordagem num sistema de telerradiologia, chamado LCD-OpenPACS, gratuito e c?digo fonte aberto. Este sistema ? uma extens?o do sistema OpenPACS que ? um sistema de comunica??o e arquivamento de imagens m?dicas que possui c?digo fonte aberto e multiplataforma desenvolvido pelo Laborat?rio de Inova??o Tecnol?gica em Sa?de (LAIS) do Hospital Universit?rio Onofre Lopes (HUOL). O m?todo proposto ? formado por cinco etapas: aquisi??o das imagens, segmenta??o, detec??o de n?dulos suspeitos, extra??o das caracter?sticas e classifica??o (elimina??o de falsos positivos). O m?todo proposto foi validado com 100 n?dulos (identificados por, pelo menos, dois radiologistas) e 101 n?o n?dulos (por exemplo, tecido, vasos sangu?neos e outras estruturas que n?o representavam n?dulos cancer?genos) e apresentou uma sensibilidade de 98,03% com 9,6 falso positivo por caso em 0,18 s. O sistema detectou n?dulos pulmonares cancer?genos (solit?rios, opacidade em vidro fosco e n?dulos justavascular) entre 3 mm e 30 mm. Entretanto, a etapa de segmenta??o do sistema ainda n?o est? apresentando resultados satisfat?rios na presen?a de n?dulos justapleurais e outras patologias graves que alteram a opacidade dos contornos pulmonares. As principais contribui??es do presente trabalho foram o desenvolvimento do novo m?todo de detec??o de n?dulos pulmonares e a proposta do sistema de telerradiologia que minimiza as altera??es do fluxo de trabalho cl?nico e o custo de implanta??o, podendo ser utilizado pelo sistema de sa?de brasileiro (SUS). Ainda s?o necess?rias mais pesquisas para aperfei?oar o sistema proposto, principalmente melhorar o processo de segmenta??o das imagens pulmonares. Como trabalhos futuros, propomos mensurar caracter?sticas dos n?dulos (por exemplo, malignidade e volume), avaliar a evolu??o do tratamento oncol?gico e seu poss?vel progn?stico. / Lung cancer is one of the most common types of cancer and has the highest mortality
rate. Patient survival is highly correlated with early detection. Computed Tomography technology
services the early detection of lung cancer tremendously by offering aminimally
invasive medical diagnostic tool. However, the large amount of data per examination makes
the interpretation difficult. This leads to omission of nodules by human radiologist.
This thesis presents a development of a computer-aided diagnosis system (CADe) tool
for the detection of lung nodules in Computed Tomography study. The system, called
LCD-OpenPACS (Lung Cancer Detection - OpenPACS) should be integrated into the
OpenPACS system and have all the requirements for use in the workflow of health facilities
belonging to the SUS (Brazilian health system). The LCD-OpenPACS made use of
image processing techniques (Region Growing and Watershed), feature extraction (Histogram
of Gradient Oriented), dimensionality reduction (Principal Component Analysis)
and classifier (Support Vector Machine). System was tested on 220 cases, totaling 296
pulmonary nodules, with sensitivity of 94.4% and 7.04 false positives per case. The total
time for processing was approximately 10 minutes per case. The system has detected pulmonary
nodules (solitary, juxtavascular, ground-glass opacity and juxtapleural) between
3 mm and 30 mm.
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Estudo da influ?ncia de tensoativos em sistemas microemulsionados na extra??o de g?lio e alum?nioLucena Neto, Marciano Henrique de 25 November 2005 (has links)
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Previous issue date: 2005-11-25 / Gallium is an important material used in the electronic industry whose demand in the world market is increasing in view of its potential applications. A selective technique is required to allow for the production of the metal, separated from aluminium. Due to the fact that microemulsions constitute an attractive alternative to metal extraction procedures, microemulsified systems have been employed as gallium-selective extraction agents. Two surfactants have been synthesized: sodium 12-N,N-diethylamino-9,10-dihydroxyestearate (AMINE) and saponified coconut oil (SCO), both produced from raw materials readily available in Northeastern Brazil. Also, the commercial extraction agent KELEX-100, conventionally used with the same purpose, has been used in this work for comparison. The optimization of the extraction process with microemulsions was carried out by investigating the influence of some parameters, namely the type of cosurfactant, the cosurfactant/surfactant (C/S) ratio, the pH and concentration of metals in the aqueous phase. Pseudoternary diagrams, which are representative of the microemulsified systems under study, have been constructed in order to establish the boundaries of the regions where the several Winsor systems are formed. An experimental planning methodology (Scheff? Net) has been used to optimize the extraction. The extraction percentage values were as high as 100% for gallium and 99.99% for aluminium for the system with KELEX-100; 96.6% for gallium and 98.8% for aluminium for the system containing AMINE; and 88% for gallium and 85% for aluminium for the system with SCO. The microemulsified system chosen for presenting the best results in gallium extraction was composed by SCO/isoamyl alcohol/kerosene/Bayer licquor with a C/S ratio of 28 and pH of the original aqueous phase of 6.0. The selectivity that has not been observed in the extraction stage was accomplished in the reextraction process using HCl. For the KELEX-100 system, gallium was reextracted at 100% with 6M HCl and aluminium was reextracted at 100% with 0.8M HCl. For the AMINE system, the reextraction percentages were also 100% for both metals, using 6M HCl for gallium and 0.5M HCl for aluminium. On the other hand, the reextraction percentages for the system with SCO were as high as 84% for gallium and 92% for aluminium, with HCl in the same concentrations as those used in the AMINE system. Finally, an optimized system was applied in the gallium extraction process employing a reciprocating perforated-plates extractor. As a result, the metal content was extracted at a recovery rate of 95% for gallium and 97% for aluminium / O g?lio ? um importante material utilizado na ind?stria eletr?nica, cuja demanda no mercado mundial est? crescendo em raz?o de suas aplica??es. A obten??o do metal necessita de um m?todo seletivo para separ?-lo do alum?nio. Sendo as microemuls?es uma alternativa atrativa para a extra??o de metais, decidiu-se utilizar sistemas microemulsionados como extratantes seletivos ao g?lio. Dois tensoativos foram sintetizados; o 12-N,Ndietil-amino-9,10-dihidroxiestearato de s?dio (AMINADO) e o ?leo de coco saponificado (OCS), obtidos de mat?rias-prima dispon?veis na regi?o Nordeste do Brasil. O extratante comercial KELEX-100, convencionalmente utilizado com essa mesma finalidade, foi usado neste trabalho para compara??o. A otimiza??o do processo de extra??o por microemuls?es foi realizada atrav?s do estudo da influ?ncia de par?metros, tais como: tipo de cotensoativo, raz?o C/T, pH e concentra??o de metais na fase aquosa. Os diagramas pseudotern?rios, representativos dos sistemas microemulsionados em estudo, foram estabelecidos no sentido de delimitar as regi?es de exist?ncia dos sistemas de Winsor. Uma metodologia de planejamento experimental (Rede Scheff?) foi usada para otimizar a extra??o. O percentual de extra??o atingiu valores de at? 100 % para o g?lio e 99,99% para o alum?nio para o sistema com o KELEX-100; 96,6 % para o g?lio e 98,8 % para o alum?nio no sistema contendo AMINADO; 88 % para o g?lio e 85 % para o alum?nio no sistema com OCS. O sistema microemulsionado selecionado por apresentar os melhores resultados na extra??o do g?lio foi composto de: OCS/?lcool isoam?lico/querosene/licor de Bayer a uma raz?o C/T igual a 28 e pH da fase aquosa igual a 6. A seletividade que faltou ? extra??o foi atingida na etapa de reextra??o utilizando-se solu??es de HCl. Para o sistema com o KELEX-100, reextraiu-se g?lio a 100% com HCl 6M e alum?nio a 100% com HCl 0,8M. No caso do sistema com AMINADO, os percentuais de reextra??o de ambos os metais tamb?m foram de 100%, usando-se HCl 6M para g?lio e HCl 0,5 M para o alum?nio. Por outro lado, para o sistema com OCS, os percentuais de reextra??o foram tais que 84% do g?lio e 92% do alum?nio foram recuperados com HCl nas mesmas concentra??es empregadas no caso do AMINADO. Um sistema otimizado foi, finalmente, aplicado na extra??o do g?lio em um extrator de pratos perfurados rec?procos (EPPR) e permitiu a extra??o deste metal com uma taxa de recupera??o de g?lio a 95% e alum?nio a 97%
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