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

Estudo do potencial antioxidante de diferentes classes de mol?culas isoladas de mel e pr?polis em c?lulas de Saccharomyces cerevisiae / Study of different molecules classes isolated from honey and propolis antioxidant activity in Saccharomyces cerevisiae cells.

Prud?ncio, Edlene Ribeiro 04 August 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-11T13:41:47Z No. of bitstreams: 1 2016 - Edlene Ribeiro Prud?ncio.pdf: 1465673 bytes, checksum: 5714fb486b0694f0e6ac0482d5b775a5 (MD5) / Made available in DSpace on 2017-05-11T13:41:47Z (GMT). No. of bitstreams: 1 2016 - Edlene Ribeiro Prud?ncio.pdf: 1465673 bytes, checksum: 5714fb486b0694f0e6ac0482d5b775a5 (MD5) Previous issue date: 2016-08-04 / Honey and propolis are produced by bees from the nectar and sap collected from plants. In the process, the phenolic compounds derived from secondary metabolism of plants are incorporated into the products mentioned. Honey and propolis samples from multiple regions have been characterized and phenolic compounds can be divided into: hydroxybenzoic acid derivatives, hydroxycinnamic acid derivatives, flavonoids and glycosylated flavonoids. In the literature, there is no consensus among the authors about the values for in vitro antioxidant activity. Moreover, these methods do not represent physiological conditions such as concentration of substrates and metabolites interaction. The yeast Saccharomyces cerevisiae is an alternative tool for a biological assays, since it is similar to mammalian cells. The main goal of this study is to compare the antioxidant potential of different phenolic compounds classes using representatives morin, rutin, chlorogenic acid and syringic acid in control strains (BY4741) and mutant (?sod1 and ?gsh1) of S. cerevisiae. They were evaluated in dose-dependent toxicity, stress tolerance, and lipid peroxidation. All tested phenolic compounds were effective in reducing intracellular oxidative damage, especially the chlorogenic acid in the control strain. When compared to stressed cells, it promoted 75% increase on cell survival rates, compared with 57% on average for the other treatments; and 60% decrease in levels of lipid peroxidation, compared to reductions close to 47% with other treatments. In mutant strains, all compounds presented similar results. Thus, two components of the class hydroxycinnamic acid, caffeic acid and caffeic acid phenethyl ester (CAPE) were tested comparatively. Both acted as an antioxidant in S. cerevisiae, however CAPE was the most toxic substance promoting the most significant increase on reduced glutathione levels among hydroxycinnamic derivatives. This result supports some related research that claims phenolic compounds protectection is related to activation of the antioxidant system as xenobiotic action of these substances / O mel e a pr?polis s?o produzidos por abelhas, a partir da coleta de n?ctar e seiva das plantas. No processo, os compostos fen?licos oriundos do metabolismo secund?rio dos vegetais s?o incorporados aos produtos mencionados. Amostras de mel e pr?polis de diferentes regi?es foram caracterizadas e o conte?do de compostos fen?licos pode ser dividido em: derivados do ?cido hidroxibenzoico, derivados do ?cido hidroxicin?mico, flavonoides e flavonoides glicosilados. Na literatura, valores de atividade antioxidante in vitro descritos divergem consideravelmente entre os autores. Al?m disso, os m?todos in vitro (DPPH, ABTS, FRAPP, dentre outros) n?o representam condi??es fisiol?gicas como concentra??o de substratos e intera??o de metab?litos. A levedura Saccharomyces cerevisie ? uma ferramenta para ensaio biol?gico, uma vez que apresenta elevada semelhan?a com c?lulas de mam?feros superiores no sistema de defesa antioxidante. O objetivo deste trabalho foi comparar o potencial antioxidante de diferentes classes de compostos fen?licos, utilizando os representantes morina, rutina, ?cido sir?ngico e clorog?nico em cepas controle (BY4741) e mutantes (?sod1 e ?gsh1) de S. cerevisiae. Foram avaliados toxidez dose-dependente, toler?ncia ao estresse e peroxida??o lip?dica. Todos os compostos fen?licos testados foram efetivos em reduzir danos oxidativos intracelulares, com destaque para o ?cido clorog?nico na cepa controle. Quando comparado ?s c?lulas estressadas, este promoveu aumentos de 75% de sobreviv?ncia, contra 57% em m?dia dos demais tratamentos; e diminui??o de 60% em n?veis de peroxida??o lip?dica, contra redu??o pr?xima a 47% dos demais tratamentos. Nas cepas mutantes, todas as subst?ncias tiveram resultados semelhantes entre si. Desta forma, outros dois componentes da classe do ?cido hidroxicin?mico, ?cido cafeico e ?ster fenet?lico do ?cido cafeico (CAPE), foram testados comparativamente. Ambos atuaram como antioxidante em S. cerevisiae, entretanto CAPE foi a subst?ncia mais t?xica e tamb?m a que promoveu aumento mais significativo de glutationa reduzida dentre os derivados hidroxicin?micos. Esse resultado corrobora com dados de estudos que apontam que a atividade protetora dos compostos fen?licos est? relacionada a ativa??o do sistema antioxidante por a??o xenobi?tica dessas subst?ncias
32

Combust?o catal?tica de metano utilizando espin?lio de cobalto proveniente de ?xidos mistos de Co, Mg e Al obtidos da calcina??o de hidr?xidos duplos lamelares / Catalytic combustion of methane using cobalt spinel from mixed Co, Mg and Al oxides obtained from the calcination of lamellar double hydroxides

Paiva, Maria Clara Adum de 04 August 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-15T11:16:01Z No. of bitstreams: 1 2016 - Maria Clara Adum de paiva.pdf: 2279180 bytes, checksum: d1de128b3d5f5984c844a68538cd255e (MD5) / Made available in DSpace on 2017-05-15T11:16:01Z (GMT). No. of bitstreams: 1 2016 - Maria Clara Adum de paiva.pdf: 2279180 bytes, checksum: d1de128b3d5f5984c844a68538cd255e (MD5) Previous issue date: 2016-08-04 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The demand for electricity production, and the need for thermoelectric use as power generating units, makes it necessary to search for less polluting matrices. In this search the catalytic combustion of methane, both from natural gas and other sources (residue disposal, for example) have shown promising. It is known the use of cobalt oxides is an alternative to the use of catalysts based on noble metals which has shown high performance. In order to potentiate the activity of the cobalt based catalyst, thus reducing both the ignition temperature and the temperature of total burning of methane, this work proposes the production of cobalt-based precursors using different types of layered double hydroxides (LDHs). Cobalt based catalysts partially substituted in layered double hydroxides (LDH Mg, Al and CO32-) were prepared by co-precipitation and impregnation with a nominal content of 9% CoII in LDH, or by impregnating a commercial hydrotalcite (HT). The LDH precursors were characterized by X-ray powder diffraction (XRD) and infrared absorption spectroscopy (FTIR). The XRD patterns indicated a LDH of 3R polytype. XRD showed the presence of Gibbisite in the HT precursor. The infrared spectra of precursor LDHs presented bands related to ?1, ?2 and ?3 vibrations of the carbonate anion, and interlayer water characteristic bands, thus in line with the XRD data. Analysis by XRD of the catalysts after calcination at 800 ?C showed the presence of periclase and spinel phases. Infrared spectra showed bands ascribed to the Mg-O and Co-O stretching in tetrahedral and octahedral sites as well as bands attributed to the Mg-O-Al bond and the cobalt spinel. The catalytic activity of these materials was investigated in the catalytic combustion of methane under kinetic regime, using predetermined reaction conditions to avoid diffusional limitations, resulting in a significant decrease in the combustion temperature, with the higher activity observed for the catalyst prepared by impregnating a commercial HT. Scanning electron microscopy (SEM) and quantitative chemical analysis (EDS) of catalysts with improved performance show both the homogeneous dispersion of the components in the sample surface and the higher aluminum content of the sample supported on HT. / A demanda de produ??o de energia el?trica, e a necessidade do uso de termel?tricas como unidades geradoras de energia, fazem com que seja necess?ria a busca por matrizes menos poluentes. Nessa busca a combust?o catal?tica do metano, tanto proveniente do g?s natural como de outras fontes (res?duo do tratamento de lixo, por exemplo), tem se mostrado promissora. Sabidamente o uso de ?xidos de cobalto ? uma alternativa, que vem mostrando alto desempenho, ao uso de catalisadores a base de metais nobres. Com o intuito de potencializar a atividade do catalisador a base de cobalto, reduzindo assim tanto a temperatura de igni??o quanto a de queima total do metano, esse trabalho prop?e sua produ??o utilizando como precursor diferentes tipos de hidr?xidos duplos lamelares (HDLs). Catalisadores ? base de cobalto parcialmente substitu?dos em hidr?xidos duplos lamelares (HDL de Mg, Al e CO32-) foram preparados por co-precipita??o e impregna??o num teor nominal de 9% de CoII em HDL, ou por impregna??o em hidrotalcita comercial (HT). Os HDLs precursores foram caracterizados por difra??o de raios?X pelo m?todo de p? (DRX) e por espectroscopia de absor??o no infravermelho (FTIR). Os difratogramas indicaram a obten??o de um HDL de politipo 3R. Por meio do DRX foi identificada a presen?a de Gibbisita no suporte de HT. Os espectros de infravermelho dos HDLs precursores presentaram bandas referentes ?s vibra??es ?1, ?2 e ?3 do ?nion carbonato, al?m de bandas caracter?sticas de ?gua interlamelar, estando portanto de acordo com os dados de DRX. A an?lise por difra??o de raios-X dos catalisadores ap?s calcina??o a 800?C mostrou apenas as fases espin?lio e pericl?sio. Os espectros de infravermelho apresentaram bandas atribu?das aos estiramentos Mg?O e Co?O em s?tios tetra?dricos e octa?dricos, assim como bandas caracter?sticas de Mg?O?Al e de Co3O4. A atividade catal?tica desses materiais foi investigada na combust?o catal?tica do metano, em regime cin?tico, empregando-se condi??es reacionais preestabelecidas de forma a evitar limita??es difusionais, obtendo-se uma significativa diminui??o na temperatura de combust?o, sendo que a maior atividade foi observada para o catalisador preparado por impregna??o em HT comercial. Foi realizada microscopia eletr?nica de varredura (MEV) e an?lise qu?mica quantitativa (EDS) para os catalisadores com melhor desempenho, mostrando tanto a dispers?o homog?nea dos componentes na superf?cie das amostras como o maior teor de alum?nio presente na amostra suportada em HT.
33

Uma proposta de livro paradid?tico como motiva??o para o ensino de matem?tica / A proposal of paradid?tico book as motivation for the teaching of mathematics

Pinto, Anildo Gon?alves 13 April 2013 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-30T11:30:49Z No. of bitstreams: 1 2013 - Anildo Gon?alves Pinto.pdf: 741613 bytes, checksum: 77ce20085faa9d488f526c25e4d6127c (MD5) / Made available in DSpace on 2017-05-30T11:30:50Z (GMT). No. of bitstreams: 1 2013 - Anildo Gon?alves Pinto.pdf: 741613 bytes, checksum: 77ce20085faa9d488f526c25e4d6127c (MD5) Previous issue date: 2013-04-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / We recognize the importance of an educational material as encouragers and contributors instruments of teaching. In this work, we conducted a historical survey of an educational material in Brazil, their relevance and contribution to the mathematics teaching and other fields of knowledge. As a contribution to the mathematics teaching, an educational mathematic text material was prepared whose main contents discuss about numerical sequences. In the next pages, will be presented an analysis of the research conducted with students and teachers from a public school located in Nil?polis city. / Reconhecemos a import?ncia dos livros paradid?ticos como instrumentos colaboradores e incentivadores do ensino. Neste trabalho fizemos um levantamento hist?rico dos livros paradid?ticos no Brasil, sua relev?ncia e contribui??o para o ensino de matem?tica e outras ?reas do conhecimento. Como contribui??o para o ensino de matem?tica, elaboramos um texto paradid?tico de matem?tica tendo como conte?do principal, sequ?ncias num?ricas. Apresentamos a an?lise da pesquisa realizada com discentes e docentes do ensino m?dio de uma escola estadual do munic?pio de Nil?polis
34

Estudo comparativo dos ?leos essenciais de esp?cies da fam?lia Myrtaceae atrav?s do perfil cromatogr?fico, an?lise multivariada e atividades biol?gicas / Comparative study of the essential oils of Myrtaceae species through the chromatographic profile, multivariate analysis and biological activities

Santos, Frances Regiane dos 19 September 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-08-18T11:50:39Z No. of bitstreams: 1 2016 - Frances Regiane dos Santos.pdf: 3889746 bytes, checksum: 193cd2f941ca3560b1dd12601120624e (MD5) / Made available in DSpace on 2017-08-18T11:50:39Z (GMT). No. of bitstreams: 1 2016 - Frances Regiane dos Santos.pdf: 3889746 bytes, checksum: 193cd2f941ca3560b1dd12601120624e (MD5) Previous issue date: 2016-09-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The Myrtaceae family comprises more than 3,500 species, which are widely distributed on all continents (except Antarctica). The chemical diversity and the biological potential of essential oils extracted from fresh leaves of Myrtaceae species cultivated in the Botanical Garden of UFRRJ were described. Six different species were studied: Eugenia uniflora L. (?pitanga?), Eugenia brasiliensis L. (?grumixama?), Psidium cattleianum Sabine (?ara???), Psidium guajava L. (?goiaba?), Syzygium cumini (?jamel?o?) and Syzygium malaccense (L.) (?jambo?). Chemical, statistical and biological methods were used, with the aid of chromatographic analysis (GC-FID and GC-MS), chemometrics (PCA and HCA statistical analysis) and biological activities (larvicide, trypanocidal, fungicidal and antioxidant) to determine these essencial oils. The essential oil of species E. uniflora L, E. brasiliensis, P.cattleianum and P. guajava showed mainly sesquiterpenes in its compositions, while the oil from S. cumini was rich in monoterpenes and S. malaccense presented, mostly, chemical constituents not derived isoprene metabolites.. The chemometric analysis of GC-MS data of the oils extracted from leaves of six species, discriminated three groups of essential oils, according to the similarity of the composition of volatile components for each species. Specifically, for the P.cattleianum and P. guajava data, the ?-caryophyllene and ?-humuleno constituents could be considered markers of Psidium genus. The biological results suggested that the essential oils of the species studied were effective as they showed larvicide and fungicidal activity . The essential oil of E. uniflora and its isolated furanodiene showed antioxidant activity, with the TBARS method, and also showed potential anti-Trypanosoma cruzi activity, which suggests that both are an interesting alternative to combat infectious diseases such as Chagas disease / A fam?lia Myrtaceae compreende mais de 3.500 esp?cies, que est?o amplamente distribu?das por todos os continentes (exceto Ant?rtida). Este trabalho descreve a diversidade qu?mica e o potencial biol?gico dos ?leos essenciais extra?dos de folhas frescas de esp?cies de Myrtaceae cultivadas no Jardim Bot?nico da UFRRJ. Seis esp?cies diferentes foram estudadas: Eugenia uniflora L.(pitangueira), Eugenia brasiliensis Lam (grumixameira), Psidium cattleianum Sabine (ara?azeiro), Psidium guajava L. (goiabeira), Syzygium cumini (jameleiro) e Syzygium malaccense (L.) Merr. & L. M. Perry (jambeiro vermelho). Os seus ?leos essenciais foram extra?dos por hidrodestila??o e avaliados com o aux?lio de an?lises cromatogr?ficas (CG-DIC e CG-EM), quimiometria (utilizando An?lise de Componentes Principais - ACP e An?lise de Agrupamentos Hier?rquicos ? AAH) e atrav?s de atividades biol?gicas (larvicida, tripanocida, fungicida e antioxidante). O ?leo essencial das esp?cies E. uniflora L, E. brasiliensis P.cattleianum e P. guajava apresentou, principalmente, sesquiterpenos em sua composi??o, enquanto o ?leo de S. cumini foi rico em monoterpenos e o de S. malaccense apresentou constituintes qu?micos n?o oriundos de metab?litos do isopreno. Os resultados obtidos atrav?s da quantifica??o e identifica??o qu?mica dos ?leos essenciais por Cromatografia em Fase Gasosa acoplada a Espectrometria de Massas (CG-EM) aplicadas ?s an?lises quimiom?tricas permitiu discriminar tr?s agrupamentos de ?leos essenciais, de acordo com a similaridade na composi??o de constituintes vol?teis para cada esp?cie. Especificamente para P. cattleianum e P. guajava os constituintes ?-cariofileno e ?-humuleno foram considerados os marcadores do g?nero Psidium. Para os ensaios biol?gicos realizados, os resultados obtidos com os ?leos essenciais das esp?cies estudadas mostraram-se eficazes quanto ? atividade larvicida e fungicida. O ?leo essencial de E. uniflora e o furanodieno isolado apresentaram atividade antioxidante pelo m?todo TBARS, e tamb?m apresentaram potencial atividade tripanocida, sugerindo que ambos sejam uma alternativa interessante para combater doen?as parasit?rias como a doen?a de Chagas
35

A Hist?ria da geometria descritiva e uma proposta de atividades para o ensino m?dio / The history of descriptive geometry and a proposal for activities for high school

Coutinho Neto, Nelson Rangel 30 August 2014 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-11T11:55:12Z No. of bitstreams: 1 2014 - Nelson Rangel Coutinho Neto.pdf: 1017081 bytes, checksum: 48847c819281a97d7502570c6852b27b (MD5) / Made available in DSpace on 2017-09-11T11:55:12Z (GMT). No. of bitstreams: 1 2014 - Nelson Rangel Coutinho Neto.pdf: 1017081 bytes, checksum: 48847c819281a97d7502570c6852b27b (MD5) Previous issue date: 2014-08-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The Descriptive Geometry had its origin during the Napoleonic Age through the mathematician Gaspard Monge. It arrived in Brazil in the early nineteenth century by imposition of D. Jo?o VI. It excelled mainly as part of the curriculum of higher education courses such as Engineering, Architecture and Arts discipline. In high school, teaching Descriptive Geometry is almost extinct, being restricted to only a few more traditional institutions. However, Descriptive Geometry is closely related to the Space Geometry, Analytical Geometry and Differential and Integral Calculus, so that its application in middle school will be of fundamental contribution to the learning of other geometric concepts / A Geometria Descritiva teve sua origem durante a Era Napole?nica atrav?s do matem?tico Gaspard Monge. Chegou ao Brasil no in?cio do s?culo XIX por imposi??o de D. Jo?o VI. Destacou-se basicamente como disciplina integrante de curr?culos de cursos superiores, tais como Engenharia, Arquitetura e Artes. No ensino m?dio, o ensino da Geometria Descritiva est? praticamente extinto, ficando restrito apenas a algumas institui??es mais tradicionais. Entretanto, a Geometria Descritiva se relaciona intimamente com a Geometria Espacial, a Geometria Anal?tica e os C?lculos Diferencial e Integral, de maneira que sua aplica??o no ensino m?dio poder? contribuir para o aprendizado de outros conceitos geom?tricos
36

Modelagem e simula??o da sedimenta??o e filtra??o utilizando o m?todo de elementos discretos / Modeling and Simulation of Sedimentation and Filtration using the Discrete Element Method

Alvim, Jo?o M?rcio sutana 21 December 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-18T11:33:32Z No. of bitstreams: 1 2016 - Jo?o M?rcio Sutana Alvim.pdf: 4276113 bytes, checksum: 115487153abb7bab43e2a012959a64e4 (MD5) / Made available in DSpace on 2017-09-18T11:33:34Z (GMT). No. of bitstreams: 1 2016 - Jo?o M?rcio Sutana Alvim.pdf: 4276113 bytes, checksum: 115487153abb7bab43e2a012959a64e4 (MD5) Previous issue date: 2016-12-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / In the classic set of unit operations of solid-liquid separation, sedimentation and filtration techniques stand out as critical processing steps for a broad spectrum of industrial activities. In this context, the proper knowledge of the properties and characteristics of the particulate systems directly involved represents an important aspect for the safe and efficient design of equipment and processes. Over the past 20 years, several methodologies were developed to study such phenomena, resulting in a huge library of sedimentation and filtration models available in the literature. This work presents a study based on the use of a particle-scale numerical simulation technique called Discrete Element Method (DEM), to describe the deposition of particulate solids in liquids. Tridimensional simulations of the sedimentation and filtration processes were carried out in a previously known flow field, as a way to test the applicability of the code and its capacity to virtually describe such processes. Cake properties, such as thickness, porosity and permeability were quantified over time and compared qualitatively and quantitatively with literature data. The effects of operational conditions, solids and liquid properties on the particulate model?s response were also investigated through a series of controlled numerical tests. The packing fraction values obtained in this work for the sedimentation process, when compared to the values found in the literature on similar conditions, showed a satisfactory agreement, with deviations smaller than 12% for all the points assessed / Dentro do conjunto cl?ssico das opera??es unit?rias de separa??o s?lido?l?quido, as t?cnicas de sedimenta??o e filtra??o se destacam como etapas de processamento cruciais para um amplo espectro de atividades da ind?stria. Neste contexto, o conhecimento adequado das propriedades e caracter?sticas dos sistemas particulados diretamente envolvidos representa um aspecto importante para o projeto seguro e eficiente de equipamentos e processos. Ao longo dos ?ltimos 20 anos, diversas metodologias foram desenvolvidas para estudar tais fen?menos, resultando em uma ampla biblioteca de modelos de sedimenta??o e filtra??o dispon?vel na literatura. O presente trabalho apresenta um estudo baseado no uso da simula??o num?rica em escala de part?cula, atrav?s do M?todo de Elementos Discretos ou DEM (do ingl?s ?Discrete Element Method?), para descrever a deposi??o de s?lidos particulados em suspens?es. Foram realizadas simula??es da sedimenta??o e filtra??o em tr?s dimens?es como forma de testar o funcionamento do c?digo e a sua capacidade de reproduzir virtualmente tais processos. As propriedades da torta, tais como espessura, porosidade e permeabilidade foram quantificadas ao longo do tempo e comparadas qualitativa e quantitativamente com dados da literatura. A sensibilidade do modelo desenvolvido a varia??es nas condi??es operacionais de simula??o e nas propriedades f?sicas do s?lido e do l?quido tamb?m foi analisada. Os dados de fra??o de s?lidos obtidos nas simula??es da sedimenta??o apresentaram uma concord?ncia satisfat?ria, quando comparados aos valores encontrados na literatura em condi??es similares, apresentando desvios menores do que 12% para todos os pontos avaliados.
37

Dialquilfosforilidrazonas derivadas de isatinas N - substitu?das com potencial atividade biol?gica / Dialkylphosphorylhydrazones derived from Nsubstituted isatins with potential biological activity.

Zampirolli, Leticia Silotti 27 May 2009 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-10-05T11:53:08Z No. of bitstreams: 1 2009 - Leticia Silotti Zampirolli.pdf: 25893124 bytes, checksum: bd44115917dd331e511dc65cd22738a1 (MD5) / Made available in DSpace on 2017-10-05T11:53:08Z (GMT). No. of bitstreams: 1 2009 - Leticia Silotti Zampirolli.pdf: 25893124 bytes, checksum: bd44115917dd331e511dc65cd22738a1 (MD5) Previous issue date: 2009-05-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / A series of new dialkylphosphorylhydrazones (phosphorohydrazidic acid, N?-[1,2-dihydro-2- oxo-(R1)-3H-indole-3-iliden]- dialkyl esters was synthesized and characterized by IR, 1H, 13C and 31P NMR and mass spectroscopy. These dialkylphosphorylhydrazones were synthesized in three steps. The first step involved the synthesis of different dialkylphosphites which are obtained by the reaction of PCl3 with three mols of the corresponding alcohols. The second step consisted of the reaction between the dialkylphosphites and hydrazine in a two phase system, leading to the formation of the dialkylphosphorylhydrazines. Finally, the last step was the condensation of these dialkylphosphorylhydrazines with different N-substituted isatins. The analysis of the 1H, 13C and 31P NMR spectra showed the existence of the two possible diastereoisomers E and Z for compounds 1, 2, 6, 10 and 12, while for the remaining compounds only the Z isomer is present. Ten of these compounds were preliminarily tested for their inhibition potential against two protozoa (Trypanosoma cruzi and Leishmania amazonensis). All compounds tested showed cell proliferation inhibition of 98% at 50 ?M for Leishmania amazonensis, whereas for T. cruzi, inhibition of epimastigote cell proliferation was found to be higher than 75% for all compounds tested except 6, which showed a 59% inhibition. These ten compounds were also evaluated against Plasmodium falciparum, affording inhibitions higher than 90% for a 1mM concentration. These compounds were also investigated for their fungicidal activity against phytopatogenic Rhizoctonia solani and Fusarium oxysporum. Compounds 9 and 11 showed a miscelial growth inhibition of 58% for Rhizoctonia solani while compound 12 afforde a 72% inhibition. Compounds 1, 2, 11 and 12 gave Fusarium oxysporum inhibition higher than 52%. Finally, the compounds synthesized were also evaluated for their inhibitory potential against lettuce seed germination and it was observed that the same compounds which showed fungicidal activity were not able to inhibit seed germination. / Uma s?rie de 16 dialquilfosforilidrazonas (?cido fosforoidraz?dico, N? -[1,2-diidro-2-oxo-(R1)- 3H- indol-3-ilideno] -, ?ster de dialquila), sendo todas in?ditas, foram sintetizadas e caracterizadas pelas t?cnicas de espectrometria de IV, RMN de 1H, RMN de 13C, RMN de 31P e massas. As novas dialquilfosforilidrazonas foram sintetizadas em tr?s etapas de rea??o. A primeira etapa consistiu na s?ntese de diferentes fosfitos de dialquila que foram obtidos atrav?s da rea??o do tricloreto de f?sforo (PCl3) com tr?s mols do ?lcool correspondente. Na segunda etapa, a rea??o dos fosfitos de dialquila com a hidrazina, em um sistema bif?sico, levou ? forma??o das dialquilfosforilidrazinas. A ?ltima etapa foi a condensa??o destas dialquilfosforilidrazinas com diferentes isatinas substitu?das. A an?lise dos espectros de RMN de 1H, RMN de 13C, RMN de 31P das dialquilfosforilidrazonas mostraram a coexist?ncia dos dois poss?veis diastereois?meros E e Z, para os compostos 1, 2, 6, 10 e 12, enquanto que para os compostos restantes observou-se apenas o diastereois?mero Z. Dos compostos sintetizados, dez foram avaliados preliminarmente quanto ao potencial inibit?rio de prolifera??o de dois protozo?rios (Trypanosoma cruzi e Leishmania amazonensis). Para Leishmania amazonensis todos os compostos testados apresentaram inibi??o da prolifera??o celular de 98 % a 50 ?M. Enquanto que para T.cruzi verificou-se inibi??o da prolifera??o celular de epimastigotas superior a 75% para todos compostos testados, a exce??o do composto (6) cuja inibi??o foi de 59 %. Esses dez compostos tamb?m foram avaliados frente ao protozo?rio Plasmodium falciparum apresentando inibi??o superior a 90 % para todos os compostos testados, a uma concentra??o de 1mM. Essas dialquilfosforilidrazonas tamb?m tiveram a a??o fungicida avaliada frente aos fungos fitopatog?nicos (Rhizoctonia solani e Fusarium oxysporum). Em Rhizoctonia solani os compostos (9) e (11) apresentaram inibi??o do crescimento miscelial de 58 %, j? o composto (12) apresentou inibi??o de 72%. Para o Fusarium oxysporum destacaram-se os compostos (1, 2, 11 e 12) com inibi??o superior a 52 %. Esses compostos tamb?m foram avaliados quanto ao potencial inibit?rio de germina??o em sementes de alface e verificouse que os mesmos compostos que apresentaram efeitos fungist?ticos, n?o inibiram a germina??o de sementes de alface.
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Curr?culo m?nimo do Estado do Rio de Janeiro: reflex?es sobre a disciplina biologia / Minimum curriculum of the State of Rio de Janeiro: Reflections on the discipline biology

Santos, Gisele Lopes do 01 June 2017 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-03-14T12:18:08Z No. of bitstreams: 1 2017 - Gisele Lopes dos Santos.pdf: 3827549 bytes, checksum: bb5ae05f3998cf1fc3f662ddc86731d0 (MD5) / Made available in DSpace on 2018-03-14T12:18:08Z (GMT). No. of bitstreams: 1 2017 - Gisele Lopes dos Santos.pdf: 3827549 bytes, checksum: bb5ae05f3998cf1fc3f662ddc86731d0 (MD5) Previous issue date: 2017-06-01 / This work has as objective reflect on the emergence and implementation of the Minimum Curriculum (CM) in the State Education Network, specifically in the Biology discipline, in 2012, presented by the State Department of Education of the State of Rio de Janeiro (SEEDUC). From the socio-historical studies of the curriculum, it is sought to understand the elements that supported the emergence and implantation of the CM and how this proposal refines the external evaluations in the state, ENEM (National High School Exam) and SAERJ (Evaluation of Education in the State of Rio de Janeiro). This work constitutes a qualitative research, based on theoretical and methodological, based on the curricular studies dialoguing with the empirical sources constituted by the documents related to the emergence and implantation of the curriculum (information of the SEEDUC website, Resolution 4.866 of February 14, 2013, Minimum Curriculum of Biology, Earnings by Results SEEDUC) and by published articles on the subject. The initial objective is that through the interbreeding of these written sources one can construct a narrative about the minimal curriculum of the biology curricular component. From the analysis of the official documents regarding the CM, with regard to the concept of skills and competences, it is possible to note its proximity to the external evaluations, since the curriculum and other strategies created by SEEDUC aim to corroborate with the increase of the index Of State education in external evaluations such as IDEB (Indicator and Development of Basic Education). The CM of Biology presents skills and competences, which SEEDUC claims to be organized progressively in the official document - from the simplest or most concrete, towards a more complex or abstract one. However, analyzing this document, the two-month course distributed in the CM of biology, it is possible to sustain that this progression of contents does not always happen, it presents in a sparse and irregular form. In this sense, it was possible to perceive when analyzing the document of the CM of Biology that the teaching continues to be presented in a fragmented way; Hindering the student to associate what he / she learns in school with his daily life. After analyzing the CM of Biology, the idea that the meanings of the concepts of competences and abilities, although approaching the cognitive-constructivist side of Perrenoud, is also moved towards Tyler's compartamentalism, when he centralizes his questions in External evaluations, the accountability curriculum and performativity / Este trabalho tem como objetivo refletir sobre o surgimento e implanta??o do Curr?culo M?nimo (CM) na rede Estadual de Educa??o, especificamente na disciplina Biologia, em 2012, apresentado pela Secretaria de Estado de Educa??o do Estado do Rio de Janeiro (SEEDUC). A partir dos estudos s?cio-hist?ricos do curr?culo, busca-se compreender os elementos que sustentaram o surgimento e implanta??o do CM e como esta proposta se afina as avalia??es externas presentes no estado, ENEM (Exame Nacional do Ensino M?dio) e SAERJ (Sistema de Avalia??o da Educa??o do Estado do Rio de Janeiro). Este trabalho constitui uma pesquisa qualitativa, a base te?rico-metodol?gica, apoiou-se nos estudos curriculares dialogando com as fontes emp?ricas constitu?das pelos documentos relativos ao surgimento e implanta??o do curr?culo (informa??es do site da SEEDUC, Resolu??o 4.866 de 14 de fevereiro de 2013, Curr?culo M?nimo de Biologia, Bonifica??o por Resultados SEEDUC) e por artigos publicados a respeito do tema. O objetivo inicial ? que se possa atrav?s do intercruzamento destas fontes escritas construir uma narrativa a respeito do curr?culo m?nimo da componente curricular biologia. A partir da an?lise dos documentos oficiais a respeito do CM, no que se refere ao conceito de habilidades e compet?ncias, nota-se sua proximidade com as avalia??es externas, visto que o curr?culo e outras estrat?gias criadas pela SEEDUC almejam corroborar com a eleva??o do ?ndice da educa??o do Estado em avalia??es externas como o IDEB (Indicador e Desenvolvimento da Educa??o B?sica). O CM de Biologia apresenta habilidades e compet?ncias, as quais a SEEDUC argumenta estar organizada de forma progressiva no documento oficial ? da mais simples ou concreta, em dire??o a uma mais complexa ou abstrata. Todavia, analisando este documento, os bimestres letivos distribu?dos no CM de biologia, ? poss?vel sustentar que esta progress?o de conte?dos nem sempre acontece, apresenta-se de forma esparsa e irregular. Neste sentido, foi poss?vel perceber ao analisar o documento do CM de Biologia que o ensino continua a ser apresentado de forma fragmentada; obstaculizando o estudante associar o que aprende na escola com seu cotidiano. Ap?s an?lise do CM de Biologia, sustenta-se a ideia de que os sentidos dos conceitos de compet?ncias e habilidades embora se aproximem da vertente cognitivoconstrutivista, de Perrenoud, tamb?m se movimenta em dire??o ao compartamentalismo de Tyler, quando centraliza suas quest?es em avalia??es externas, no curr?culo do accountability e na performatividade.
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Estudo te?rico das rea??es de abstra??o e adi??o do radical hidroxila com o 2,5-dimetilfurano / Theoretical study of abstraction and addiction reactions of hydroxyl radical with 2,5-dimethylfuran

Santos, Than?zia Ferraz 28 August 2015 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-30T17:17:07Z No. of bitstreams: 1 2015 - Than?zia Ferraz Santos.pdf: 1742658 bytes, checksum: 07706cbaaa52be04cb7ec04d0d453fa2 (MD5) / Made available in DSpace on 2017-05-30T17:17:07Z (GMT). No. of bitstreams: 1 2015 - Than?zia Ferraz Santos.pdf: 1742658 bytes, checksum: 07706cbaaa52be04cb7ec04d0d453fa2 (MD5) Previous issue date: 2015-08-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / In this work, potential energy surfaces for the reactions of hydroxyl radical and 2,5-dimethylfuran were studied using the Density Functional Theory. The stationary points, such as reactants, pre-barrier complex, transition states and products were located at BHandHLYP/aug-cc-pVDZ and M06-2X-cc-pVDZ levels by geometry optimization, followed by the calculations of vibrational frequencies. Single point calculations using CCSD(T) were also explored. Thermodynamics properties of enthalpy, entrophy and Gibbs free energies have been determinated at 298,15 K within the conventional equations of Statistical Thermodynamics. The results suggest different addition mechanisms, since an analysis of the potential energy surface (PES) in BHandHLYP/ aug-cc-pVDZ points to paths going through a pi-type intermediary, while in M06-2X/aug-cc-pVDZ the intermediary would have a sigma-type interaction. About the abstraction reactions, only the PES obtained in M06-2X/aug-cc-pVDZ level points to the formation of a pre-barrier complex. The rate coefficients have been determined on the basis of the Variational Transition State Theory, with the kcvt program. The coefficient obtained at CCSD(T)/aug-cc-pVDZ//BHandHLYP/aug-cc-pVDZ for the mechanism which includes the participation of ?-PC is ???????=48,4?10?11, cm? molec-1 s-1, approximately 4 times higher than the experimental rate coefficient. Deviations of this magnitude are considered satisfactory in theoretical calculation of kinetic parameters. Addition of OH should be the main degradation pathway for furan and its derivatives, during daytime. Moreover, it was possible to clarify the effect of the formation of pre-barrier complexes in the reactions between DMF and OH radicals and propose rate coefficients in the high temperature region, which can be applied in combustion studies / Neste trabalho, as superf?cies de energia potencial para as rea??es do radical hidroxila (OH) com o 2,5-dimetilfurano (DMF) foram estudadas em detalhes, utilizando a Teoria do Funcional de Densidade. Pontos estacion?rios como reagentes, complexos pr?-barreira, estados de transi??o e produtos foram localizados por procedimentos de otimiza??o de geometria, acompanhado do c?lculo das frequ?ncias vibracionais, em n?veis BHandHLYP/aug-cc-pVDZ e M06-2X/aug-cc-pVDZ. C?lculos single point a partir da metodologia coupled-cluster com simples e duplas excita??es com tratamento perturbativo das triplas conectadas, CCSD(T), tamb?m foi explorado. Propriedades termodin?micas de entalpia, entropia e energia livre de Gibbs foram calculadas a 298,15 K atrav?s das equa??es da Termodin?mica Estat?stica. Os resultados sugerem mecanismos de adi??o diferentes, j? que uma an?lise da superf?cie de energia potencial (SEP) em BHandHLYP/aug-cc-pVDZ aponta para caminhos passando por um intermedi?rio do tipo pi, enquanto em M06-2X/aug-cc-pVDZ o intermedi?rio seria do tipo sigma. Na abstra??o, apenas a SEP obtida em M06-2X/aug-cc-pVDZ aponta para a forma??o de um intermedi?rio pr?-barreira. Coeficientes de velocidade foram determinados com base na Teoria do Estado de Transi??o Variacional, com aux?lio do programa kcvt. O coeficiente CCSD(T)/aug-cc-pVDZ//BHandHLYP/aug-cc-pVDZ para o mecanismo que inclui a participa??o do ?-PC ? de ???????=48,4?10?11 cm? molec-1 s-1, superestimado em rela??o ao coeficiente experimental em aproximadamente 4 vezes. Desvios dessa magnitude s?o esperados em c?lculos te?ricos, especialmente quando envolvem mol?culas volumosas. Pode-se constatar que a adi??o de OH deve ser a principal rota de degrada??o para o furano e seus derivados durante o dia. Al?m disso, foi poss?vel esclarecer o efeito da forma??o de intermedi?rios pr?-barreira nas rea??es entre DMF e o radical OH.
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L?gica matem?tica e estrat?gias para a solu??o de problemas matem?ticos / Mathematical logic and strategies for solving mathematical problems

Silva, Pablo Vieira Carvalho 30 June 2016 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-05-31T17:28:56Z No. of bitstreams: 1 2016 - Pablo Vieira Carvalho Silva.pdf: 1591495 bytes, checksum: 23e5c1de4092f3df312f440079012ae0 (MD5) / Made available in DSpace on 2017-05-31T17:28:56Z (GMT). No. of bitstreams: 1 2016 - Pablo Vieira Carvalho Silva.pdf: 1591495 bytes, checksum: 23e5c1de4092f3df312f440079012ae0 (MD5) Previous issue date: 2016-06-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The mathematical logic has been removed and forgotten from the curriculum minimum of basic education for some time, despite the clear benefit that it can add to the student?s cognitive not only in mathematics study but also in his day by day decision-making. This study aims to rescue the discussion of its importance to the study in the basic levels, not doing it by traditional ways, but through problem solving techniques also using the Polya phases. Joining to this work, there are activities that were applied to a first year group of high school at a public school in Rio de Janeiro. / A l?gica matem?tica h? algum tempo foi retirada e esquecida do curr?culo m?nimo do ensino b?sico da educa??o brasileira, mesmo diante dos claros benef?cios que a mesma pode acrescentar ao cognitivo do educando n?o s? no estudo da matem?tica como em tomadas de decis?es do seu dia a dia. Este trabalho tem por finalidade resgatar a discuss?o de sua import?ncia para o estudo nas s?ries b?sicas, n?o o fazendo por vias tradicionais, mas sim atrav?s de t?cnicas de resolu??o de problemas utilizando tamb?m para isso as fases de Polya. Junto deste trabalho, apresentamos atividades aplicadas ao primeiro ano do ensino m?dio de uma escola estadual do Rio de Janeiro

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