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.

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

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-06-06T12:34:21Z No. of bitstreams: 1 2010 - Alessandra Medeiros Ribeiro .pdf: 4846590 bytes, checksum: 525d2754e1be01d1117fe6e9f3362d1f (MD5) / Made available in DSpace on 2017-06-06T12:34:21Z (GMT). No. of bitstreams: 1 2010 - Alessandra Medeiros Ribeiro .pdf: 4846590 bytes, checksum: 525d2754e1be01d1117fe6e9f3362d1f (MD5) Previous issue date: 2010-03-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil. / Spectroscopic studies for several comercial flavonoids (flavone (FVA), alphanaphthoflavone (?-NAF), beta-naphthoflavone (?-NAF), thioflavone (TFA), S,Sdioxythioflavone (SDF), flavanone (FNA) and quercetin (QUE)), natural flavonoids (biflavonoids such as agatisflavone (ATF), 7?-O-methylagatisflavone (OMA), amentoflavone (AMF) and (DOF)) and thiochromanone (TCR) were performed in different solvents (acetonitrile (ACN), ethanol (ETOH), cyclohexane (CEX), dichloromethane (DCM) and milli-Q water (AD)). Irradiation of TFA, SDF and TCR in acetonitrile, employing the nanosecond laser flash photolysis, lead to the formation of their corresponding triplet excited state. Fluorescence emission spectroscopy studies showed that commercial and natural flavonoids and thiochromanone are not fluorescent. UV/visible spectroscopy studies for QUE, ATF, OMA, AMF and DOF, in the same previous solvents, revealed that for these flavonoids the ground-state absorption spectrum in polar solvents, such as water or PBS (pH=7.4), is completely different than the obtained in dichloromethane. This difference is more pronounced for ATF. For DOF the absorption spectrum in water shows remarkable variations when compared to that in PBS. The interaction between BSA and the flavonoids QUE, ATF, OMA, AMF and DOF in PBS solution, pH = 7.4, was studied by UV/visible spectroscopy, fluorescence emission spectroscopy, circular dicroism and molecular modelling. From these studies it was clearly demonstrated that the interaction observed was directly dependent on the flavonoid concentration and almost independent on temperature variation. The ground state absorption spectrum for BSA showed a hypsochromic effect on the absorption band around 208 nm, corresponding to the n?* transition of the BSA ?-helix structure, as a function of flavonoid concentration. Similar behavior was observed for the absorption at 280 nm, corresponding to the tryptophan absorption in BSA. The fluorescence emission spectrum for BSA in the presence of QUE, ATF, OMA, AMF and DOF, in PBS, at T = 22?C, 27?C, 32?C, 37?C and 42?C, shows a blue-shift on the protein emission as a function of flavonoid concentration. These results suggest that the BSA chromophore is in a more hydrophobic environment when compared with that sensed by the protein in the absence of the flavonoid. In this case, quenching of BSA fluorescence (tryptophan residues) was clearly observed with the high values obtained for the quenching rate constant kq (? 1013 to 1014 L/mol.s) indicating a static quenching process. The distance (r) observed for the tryptophan residues and the flavonoids was smaller than 7 nm, which indicates that there is a reasonable probability for a non-radiative energy transfer process between tryptophan and the flavonoids, based on the F?rster theory for energy transfer. Circular dicroism results at T = 25?C, 37?C and 42?C revealed a significant decrease on the ?-helix percentage for BSA at 208 nm and 222 nm, corresponding to the n?* transition for the secondary structure of BSA, as a function of flavonoid concentration. These effects can be attributed to the formation of a complex BSA/flavonoid which can induce conformational variations on the BSA structure. Molecular modelling indicates that the main regions for the interaction between flavonoids and ASB are located in hydrophobic cavities on the sub-domains IB and IIA, which contain tryptophan residues (Trp-158 and Trp-237). A large hydrophobic cavity containing the Trp-237 is present in the sub-domain IIA, which is responsible for the formation of the complex flavonoid-BSA through a strong interaction flavonoid-tryptophan. / Estudos espectrosc?picos para diversos flavon?ides comerciais (flavona (FVA), alfanaftoflavona (?-NAF), beta-naftoflavona (?-NAF), tioflavona (TFA), S,S-di?xidotioflavona (SDF), flavanona (FNA) e quercetina (QUE)), flavon?ides naturais (biflavon?ides como agatisflavona (ATF), 7?-O-metilagatisflavona (OMA), amentoflavona (AMF) e diidroochnaflavona (DOF)) e tiocromanona (TCR), foram realizados em diferentes solventes (acetonitrila (ACN), etanol (ETOH), cicloexano (CEX), diclorometano (DCM) e ?gua millliQ (AD)). A irradia??o de TFA, SDF e TCR, em acetonitrila, por fot?lise por pulso de laser de nanossegundo, levou ? forma??o de seus respectivos estados excitados triplete. Por espectroscopia de fluoresc?ncia, verificou-se que os flavon?ides comerciais e naturais, e a tiocromanona n?o apresentam emiss?o de fluoresc?ncia. Por espectroscopia de absor??o no ultravioleta/vis?vel (UV-Vis) para QUE, ATF, OMA, AMF e DOF, nestes solventes, percebeu-se que os espectros em presen?a de solventes polares, como AD, foram bem diferentes dos espectros em DCM, principalmente, para ATF, e os espectros em solu??o de tamp?o PBS (pH = 7,4) foram semelhantes aos em AD, exceto para DOF, apresentando mudan?as substanciais. A intera??o entre ASB e os flavon?ides (QUE, ATF, OMA, AMF e DOF) em solu??o tamponada (PBS, pH = 7,4) foi estudada por espectroscopia no ultravioleta/vis?vel, espectroscopia de emiss?o de fluoresc?ncia, dicro?smo circular e modelagem molecular sendo diretamente dependente da concentra??o adicionada de flavon?ides e muito pouco dependente com a varia??o da temperatura. No UV-Vis ocorreu deslocamento para o azul das bandas de absor??o pr?ximas a 208 nm (correspondente a ASB, referente ?s transi??es n?* da estrutura ?-h?lice da albumina) e 280 nm (correspondente ao triptofano da ASB), em fun??o do aumento de concentra??o dos flavon?ides. Na espectroscopia de fluoresc?ncia (T = 22?C, 27?C, 32?C, 37?C e 42?C) houve deslocamento para o azul na emiss?o da prote?na com o aumento da concentra??o dos flavon?ides, sugerindo que o crom?foro da ASB est? em um ambiente mais hidrof?bico em rela??o ?quele quando para ASB livre. Neste caso, observou-se supress?o da fluoresc?ncia de ASB (res?duos de triptofano), como consequ?ncia de um processo de supress?o est?tica como demonstrado pelos altos valores observados para kq (? 1013 a 1014 L/mol.s). A dist?ncia entre os res?duos de triptofano e os flavon?ides (r) foi menor que 7 nm, um indicativo da grande probabilidade de ocorrer transfer?ncia de energia entre ASB e flavon?ides, de acordo com a teoria de transfer?ncia de energia n?o-radiativa de F?rster (Teoria de F?rster). No dicro?smo circular (T = 25?C, 37?C e 42?C) foi verificada uma diminui??o do % de ?-h?lice da ASB em 208 nm e 222 nm (regi?es de transi??o n?* da estrutura secund?ria ?-h?lice da ASB no espectro de absor??o UV), devido ao aumento de concentra??o dos flavon?ides. Esses efeitos podem ser atribu?dos ? forma??o de um complexo flavon?ide-ASB que pode estar induzindo varia??es conformacionais na ASB. Por modelagem molecular, atrav?s do programa docking, percebeuse que as regi?es principais para a liga??o dos flavon?ides com os s?tios de liga??o da ASB est?o localizadas em cavidades hidrof?bicas nos subdom?nios IB e IIA (consistentes com os s?tios I e II) e os res?duos de triptofano (Trp-158 e Trp-237) de ASB est?o nesses subdom?nios, respectivamente. Existe uma grande cavidade hidrof?bica presente no subdom?nio IIA, onde os flavon?ides podem se ligar com o res?duo de triptofano Trp-237 (melhor s?tio de liga??o), formando o complexo flavon?ide-ASB.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-07-27T13:08:18Z No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) / Made available in DSpace on 2016-07-27T13:08:18Z (GMT). No. of bitstreams: 1 2011 - Queli Cristina Fidelis.pdf: 8250271 bytes, checksum: f51d246c251bca4327f02da1e892ff77 (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico, CNPq, Brasil. / This work describes the phytochemical study of the stems and leaves of Ouratea ferruginea Engl., Ochnaceae. The material for study was collected in the campus of Embrapa in Bel?m, Par? state, and identified by Dra Silvane Taveres Rodrigues. The compounds described in this phytochemistry investigation were isolated by the solvents partition and chromatographyc techniques of the extracts obtained by maceration at room temperature with hexane, ethyl acetate and methanol. The structures were determined through analysis of data provided by IR, 1H and 13C NMR (1D an 2D techniques), mass spectrometry including GCMS and HPLC-MS of natural compounds and some derivatives. From the stem dichloromethane extract friedelin, friedelinol, sitosterol, stigmasterol, campesterol, 3-b-O-Dglucopyranosyl- stigmasterol, 2,6-dimethoxy?benzoquinine, 2,6-dimethoxy-hydroquinone, the isoflavones: 5,4'-dihydroxy-7,3',5'-trimethoxy-isoflavone, 5-hydroxy-7,3',4',5'-tetramethoxyisoflavone, 5,4'-dihydroxy-7,3'-dimethoxy-isoflavone, 7,5-dihydroxy-3',4',5'-trimethoxyisoflavone, 7,5,4?-trihydroxy-3?,5?-dimethoxy-isoflavone, and ferulic and syringic aldehyde were isolated. From the dichloromethane partition of the methanol extract of the stem vanillic acid, 4 ((1E)-3-hydroxy-1-propenyl)-2-methoxyphenol and 3,5-dimethoxy-4-hydroxydihydrocinamaldehyde were isolated. From hexane fraction of methanol extract from the leaves lupeone was isolated, and from the dichloromethane methanol partition were identified the biflavonoids amentoflavone and 7-methyl-amentoflavone, known as sequoiaflavone, along with syringic acid. From the ethyl acetate of the methanol extracts partition the epicatechin which absolute configuration was defined by circular dichroism spectral analysis was isolated. The sequioflanove is been identified in Ochnaceae for the first time. From the polar fraction the total phenol were determined by adapted Folin-Denis and precipitation with casein methods and by NMR spectral analysis. / Este trabalho descreve o estudo fitoqu?mico de caule e folhas da esp?cie vegetal Ouratea ferruginea Engl, Ochnaceae. O material para estudo foi coletado no campus da Embrapa em Bel?m do Par? e identificado pela Dra Silvane Tavares Rodrigues. As subst?ncias descritas nesta investiga??o fitoqu?mica foram isoladas atrav?s de parti??o com solventes e t?cnicas cromatogr?ficos de extratos obtidos atrav?s de macera??o a frio com hexano, acetato de etila e metanol. As estruturas foram determinadas atrav?s da an?lise de dados fornecidos por espectrometria na regi?o do infravermelho, RMN 1H e 13C (t?cnicas 1D e 2D), de massas incluindo CG-EM e CLAE-EM das subst?ncias naturais e de alguns derivados. Do extrato em diclorometano do caule foram isolados friedelina, friedelinol, sitosterol, estigmasterol, campesterol, 3-b-O-D-glicopiranosil-estigmasterol, 2,6-dimetoxi benzoquinona, 2,6-dimetoxi hidroquinona, as isoflavonas 5,4?-diidroxi-7,3?,5?-trimetoxiisoflavona, 5,4?-diidroxi-7,3?-dimetoxi-isoflavona, 5-hidroxi-7,3?,4?,5?-tetrametoxiisoflavona, 7,5-diidroxi-3?,4?,5?-trimetoxi-isoflavona, 7,5,4?-triidroxi-3?,5?-dimetoxiisoflavona, al?m dos alde?dos sir?ngico e fer?lico. Da parti??o em diclorometano do extrato metan?lico do caule foram isolados ?cido van?lico, 4((1E)-3-hidroxi-1-propenil)-2- metoxifenol e 3,5-dimetoxi-4-hidroxi-diidrocinamalde?do. Das folhas foi isolada a lupeona na parti??o em hexano do extrato metan?lico; e na parti??o em diclorometano foram identificados os biflavon?ides amentoflavona e 7-metil-amentoflavona, conhecida como sequoiaflavona, e o ?cido sir?ngico. Na parti??o em acetato de etila foi isolado a epicatequina cuja configura??o absoluta foi definida com an?lise do espectro de dicro?smo circular. A sequioflavona est? sendo registrada pela primeira vez em Ochnaceae. Das fra??es polares foram determinados o teor de fen?is totais e taninos por m?todos de Folin-Denis e precipita??o com case?na, adaptados, al?m de an?lise com espectros de RMN.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-13T12:25:00Z No. of bitstreams: 1 2016 - Sheyla Moreira Gon?alves.pdf: 3716146 bytes, checksum: eaee6e62414cd3d497528f597f1abab5 (MD5) / Made available in DSpace on 2016-10-13T12:25:00Z (GMT). No. of bitstreams: 1 2016 - Sheyla Moreira Gon?alves.pdf: 3716146 bytes, checksum: eaee6e62414cd3d497528f597f1abab5 (MD5) Previous issue date: 2016-02-23 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The use of active packaging incorporated with natural antimicrobials as essential oils (EOs) for food preservation is a modern concept for the food industry. The objective of this study was to characterize cellulose acetate film (CA) incorporated with EOs and their combinations and/or added plasticizer, evaluating the influence of additives on the behavior of these materials. It is characterized as the thickness of the films, visual aspect, chemical structure, surface, mechanical strength, water vapor rate of transmission (WVRT) and antimicrobial activity. Through technique "casting" were obtained films incorporated with 50% (w/v) of EOs oregano or cinnamon or sweet fennel or combinations thereof and/or glycerol (5, 10, 20 and 30% (w/v)). Having as controls only films containing 50% (w/v) glycerol, and CA pure film, a total 41 treatments. The incorporation of EOs did not change the thickness and transparency of the films, but it reduced the WVRT. The color parameters L *, a* and b* were affected by the incorporation with EOs and/or glycerol the films exhibited clear with different colors compared with the AC pure film. Incorporating the most EOs cause increased tensile strength (TS) of the modulus of elasticity (ME) and reduced elongation at break (EB), except for the film with fennel EO (FEO) who presented plasticizer power differing from the other for all the evaluated mechanical parameters. The drilling force (DF) has increased to most films EOs incorporated with the exception of the film incorporated with the three EOs. The scanning electron microscopy (SEM) images revealed that most of the EOs and their combinations did not cause changes in the surface and cross-sectional area of the films, except the film with FEO. In the spectra of infrared spectroscopy with Fourier transform (FTIR), it observed that the interactions between the polymer matrix and most EOs were similar except for the film with FEO. As for the antibacterial efficiency in vitro, only the film incorporated with FEO showed no efficacy against Staphylococcus aureus (Gram +) and Escherichia coli (Gram +). It was observed that glycerol causes increased thickness and WVRT the AC films, however, the active films with EOs does not modify the parameter to most treatments. Transparency was not affected for most films. The addition of glycerol for most films incorporated with EOs caused reduction of TS, the ME and increased EB and DF. From the SEM pictures it can be observed that the glycerol promoted the emergence of porous structures, networked or compact, depending on the EO concentration and glycerol. The FTIR spectral showed that glycerol has different interactions, depending on the embedded EOs. The antibacterial efficiency of films with EO oregano or cinnamon or oregano more cinnamon has been improved with the presence of glycerol, while the others were not affected. In the face of changes in functional properties observed, it appears that with the additivation materials it is necessary to characterize them to define their applicability / O emprego de embalagens ativas incorporadas com antimicrobianos naturais, como os ?leos essenciais (OEs) para conserva??o de alimentos, representa um conceito moderno para a ind?stria aliment?cia. Objetivou-se neste trabalho caracterizar filmes de acetato de celulose (AC) incorporados com OEs e suas combina??es e/ou adi??o de plastificante, avaliando as influ?ncias da aditiva??o no comportamento f?sico e mec?nico destes materiais. Caracterizou-se os filmes quanto ? espessura, aspectos visuais, estrutura qu?mica, superf?cie, resist?ncia mec?nica, taxa de transmiss?o ao vapor de ?gua (TTVA) e atividade antimicrobiana. Atrav?s da t?cnica ?casting? foram obtidos filmes incorporados com 50% (p/v) de OEs de or?gano, canela, funcho doce ou suas combina??es e/ou glicerol (5, 10, 20 e 30% (p/v)). Tendo como controles filmes contendo somente 50% (p/v) de glicerol, e filme de AC puro, totalizando 41 tratamentos. A incorpora??o de OEs n?o modificou a espessura e transpar?ncia dos filmes, por?m causou redu??o da TTVA. Os par?metros de cor L*, a* e b* foram afetados pela incorpora??o de OEs e/ou glicerol tendo os filmes apresentado-se claros com diferentes cores em compara??o com o filme de AC puro. A incorpora??o da maioria dos OEs causou aumento da resist?ncia ? tra??o (RT), do m?dulo de elasticidade (ME) e redu??o do alongamento na ruptura (AR), com exce??o para o filme com OE de funcho (OEF) que apresentou poder plastificante diferindo dos demais para todos os par?metros mec?nicos avaliados. A for?a de perfura??o (FP) aumentou para a maioria dos filmes incorporados com OEs, a exce??o do filme incorporado com os tr?s OEs. As imagens de microscopia eletr?nica de varredura (MEV) revelaram que a maioria dos OEs e suas combina??es n?o causaram mudan?as na superf?cie e regi?o transversal dos filmes, a exce??o do filme com OEF. Nos espectros da espectroscopia no infravermelho com transformada de Fourier (FTIR), notou-se que as intera??es entre a matriz polim?rica e a maioria dos OEs foram semelhantes, com exce??o para o filme com OEF. Quanto ? efici?ncia antibacteriana in vitro, somente o filme incorporado com OEF n?o apresentou efetividade contra Staphylococcus aureus (Gram +) e Escherichia coli (Gram -). Foi observado que o glicerol causou aumento da espessura e TTVA nos filmes de AC, por?m, nos filmes ativos com OEs n?o modificou o par?metro para maioria dos tratamentos. A transpar?ncia n?o foi afetada para a maioria dos filmes. A adi??o de glicerol para a maioria dos filmes incorporados com OEs causou redu??o da RT, do ME e aumento do AR e FP. Pelas imagens do MEV observa-se que o glicerol promoveu o surgimento de estruturas porosas, em rede ou compactas, dependendo do OE e concentra??o de glicerol. Os espectros da FTIR demonstraram que o glicerol apresentou diferentes intera??es, dependendo do OE incorporado. A efici?ncia antibacteriana dos filmes com OE de or?gano ou canela ou or?gano mais canela foi melhorada com a presen?a de glicerol, enquanto os demais n?o sofreram influ?ncia. Diante das varia??es nas propriedades funcionais observadas, verifica-se que com a aditiva??o dos materiais ? necess?rio caracteriza??o para definir sua aplicabilidade

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-19T12:48:57Z No. of bitstreams: 1 2016 - Alexandre Rodrigues de Assis.pdf: 4979327 bytes, checksum: 5e0ad89b3f3293076de6fcf16e11f879 (MD5) / Made available in DSpace on 2016-10-19T12:48:57Z (GMT). No. of bitstreams: 1 2016 - Alexandre Rodrigues de Assis.pdf: 4979327 bytes, checksum: 5e0ad89b3f3293076de6fcf16e11f879 (MD5) Previous issue date: 2015-11-30 / The continuous and accentuated development of the digital technologies has provided challenging situations in the educational field. In this context, the use of mobile devices can represent a beneficial time for reflections on the creation of favorable environments for mathematical learning. Particularly the touchscreen devices can contribute to the formation of a new learning space. This research aimed to design, implement and analyze isometries activities using tablet on an ongoing teachers training - in Normal Mode - in Middle Level. The research with characteristics of Design was guided by the following questions: i) how are the touchscreen performances in the resolution of the proposed tasks?; and ii) how do the students handle doing rotations in GeoGebra touch and in Geometric Constructer? As data collection instruments were used (a) researcher records, (b) students' records for the proposed activities, (c) icons sheet, (d) recording audio and video, and (e) recording of touches made in tablet screen using Screen Recorder Pro. The study field was conducted with 10 students of the 1st year in a public school in the metropolitan region of Rio de Janeiro. Besides theoretical reflections we conducted the analysis of episodes that emerged from implementations with GeoGebra touch and Geometric Constructer. By a survey with characteristics of Design and marked theoretical referential in vigotskianas conceptions, we conducted theoretical reflections about the gestures and touchscreen manipulation and we illustrate the analysis of interactions that emerged from implementations with GeoGebra touch and Geometric Constructer. The results indicate that the use of tablets, linked to the development of tasks considering the specificities of the software contributes to the construction of mathematical concepts and cognitive development. The analysis also revealed that touchscreen manipulation contributed to perform rotations using two or three fingers and performances that refer to the composition of isometric transformations, providing the (re)construction of meanings. / O cont?nuo e acentuado desenvolvimento das tecnologias digitais tem propiciado situa??es desafiadoras no ?mbito educacional. Nesse ?mbito, o uso de aparatos m?veis pode representar um momento prof?cuo para reflex?es sobre a cria??o de ambientes favor?veis ao aprendizado matem?tico. Particularmente, os dispositivos touchscreen podem contribuir para a constitui??o de um novo espa?o de aprendizagem. Esta pesquisa teve como objetivos elaborar, implementar e analisar atividades de isometrias, utilizando tablet, em um curso de forma??o de professores - na Modalidade Normal - em N?vel M?dio. A pesquisa com caracter?sticas de Design foi orientada pelos seguintes questionamentos: i) como s?o as performances de touchscreen na resolu??o das tarefas propostas?; e ii) como os discentes manipulam fazendo rota??es no GeoGebra touch e no Construtor Geom?trico? Como instrumentos de coleta de dados foram utilizados (a) registros do pesquisador, (b) registros dos alunos para as atividades propostas, (c) folha de ?cones, (d) grava??es em ?udio e em v?deo, e (e) grava??o dos toques realizados na tela do tablet utilizando Screen Recorder Pro. O trabalho de campo foi desenvolvido com 10 alunos do 1? ano em uma escola p?blica estadual da regi?o metropolitana no Rio de Janeiro. Al?m de reflex?es te?ricas realizamos a an?lise de epis?dios que emergiram de implementa??es com o GeoGebra touch e Construtor Geom?trico. Mediante uma pesquisa com caracter?sticas de Design e referencial te?rico balizado em concep??es vigotskianas, realizamos reflex?es te?ricas acerca dos gestos e manipula??es touchscreen e ilustramos a an?lise de intera??es que emergiram de implementa??es com o GeoGebra touch e Construtor Geom?tricor. Os resultados indicam que o uso de tablets, vinculada ? elabora??o de tarefas considerando as especificidades do software, contribui para constru??o de conceitos matem?ticos e desenvolvimento cognitivo. As an?lises tamb?m revelaram que manipula??es touchscreen contribuiram para realizar rota??es utilizando dois ou tr?s dedos e performances que remetem ? composi??o de transforma??es isom?tricas, propiciando a (re)elabora??o de significados

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-04T11:32:19Z No. of bitstreams: 1 2016 - Felipe Machado Trombete.pdf: 1613295 bytes, checksum: 957f0b025def400e446f7c3176c76b4c (MD5) / Made available in DSpace on 2017-01-04T11:32:19Z (GMT). No. of bitstreams: 1 2016 - Felipe Machado Trombete.pdf: 1613295 bytes, checksum: 957f0b025def400e446f7c3176c76b4c (MD5) Previous issue date: 2016-03-18 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Mycotoxins are natural contaminants produced by filamentous fungi and they are widely present in food. In wheat grains, the presence of trichothecenes produced by Fusarium spp. and also aflatoxins, produced by Aspergillus spp. are a serious public health problem because they are toxic metabolites to man and animals that remain stable during the industrial processes to which wheat is subjected when manufacturing derived products. One way to reduce such contaminants is to use ozone (O3) in food processing. Due to its high potential as an oxidant, O3 may react with mycotoxins and reduce their toxicity due to molecular degradation. This research aimed to evaluate the effects of different conditions of ozonation on the i) reduction in mycotoxins levels (deoxynivalenol and total aflatoxins); ii): reduction in total fungal count; iii) the effects on chemical, mineral and technological profiles and; iv) the possible differences sensorial profile of the flour obtained from the ozonized grains. In a second phase of this project, a methodology for determination of D3G (deoxynivalenol-3-glucoside), a masked form of DON, using High Performance Liquid Chromatography with photodiode array detector (HPLC-PDA) was optimized and in-house validated. Results obtained from ozonation study showed that O3 reduced total fungal count in approximately 3.0 cycles log CFU/g of wheat grain and deoxynivalenol and total aflatoxins contamination up to 64.3% and 48.0%, respectively. The gaseous ozonation can be applied without negatively changing the chemical, technological and sensory characteristics of the grains and can be considered an excellent method for remediation of fungal and mycotoxin contaminations. Also, the method optimized and in-house validated for determination of D3G by HPLC-PDA showed adequate results and, it could be considered an alternative to mass spectrometry determination of D3G in wheat grains. / Micotoxinas s?o contaminantes naturais, produzidos por fungos filamentosos e, podem ocorrer em altos n?veis nos alimentos. Nos gr?os de trigo, a presen?a de tricotecenos, um grupo de micotoxinas produzidas por Fusarium spp. e, aflatoxinas, produzidas por Aspergillus spp., representam um importante problema de sa?de p?blica por serem t?xicas ao homem e animais e muito est?veis aos processos no qual o trigo ? submetido para obten??o de produtos industrializados. Uma forma de reduzir a contamina??o dos alimentos por micotoxinas ? atrav?s do uso do oz?nio (O3) no processamento do alimento. Devido ao alto potencial oxidante do O3, esse pode degradar as mol?culas das micotoxinas, tendo como consequ?ncia a elimina??o ou redu??o de seus efeitos t?xicos. Essa pesquisa teve como objetivos principais avaliar os efeitos de diferentes condi??es de ozoniza??o na i) redu??o de micotoxinas (desoxinivalenol e aflatoxinas) em gr?os de trigo; ii) redu??o nos n?veis de fungos filamentosos; iii) influ?ncia nos par?metros qu?micos, perfil de minerais e par?metros tecnol?gico dos gr?os e da farinha obtida ap?s o processamento e; iv) influ?ncia nas caracter?sticas sensoriais da farinha elaborada a partir dos gr?os ozonizados. Em uma segunda etapa do projeto, um m?todo para determina??o de uma forma modificada do desoxinivalenol (DON), o desoxinivalenol-3-glicos?deo (D3G) foi otimizada e validada intralaboratorialmente, utilizando cromatografia l?quida de alta efici?ncia com detector de arranjo de diodos (CLAE-DAD). Os resultados obtidos dos ensaios de ozoniza??o demonstraram que o O3, nas condi??es experimentais utilizadas, reduziu a contagem de fungos totais em cerca 3,0 logs UFC/g de gr?os e a contamina??o por desoxinivalenol e aflatoxinas totais em at? 64,3 % e 48,0 %, respectivamente. O processo de ozoniza??o n?o influenciou de modo negativo a qualidade qu?mica, tecnol?gica e sensorial dos gr?os de trigo, podendo ser utilizado como um excelente m?todo para remedia??o da contamina??o dos gr?os por fungos e micotoxinas. Resultados adequados tamb?m foram obtidos na valida??o do m?todo de determina??o de D3G por CLAE-DAD, demonstrando que o m?todo ? confi?vel para a determina??o dessa forma mascarada do DON em gr?os e trigo e, pode ser utilizado como um m?todo alternativo a espectrometria de massas para tal an?lise.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-12T13:19:24Z No. of bitstreams: 1 2015 - Wellington Gon?alves Lemos.pdf: 9868472 bytes, checksum: c653096dd1677c18027859c47248be69 (MD5) / Made available in DSpace on 2017-01-12T13:19:24Z (GMT). No. of bitstreams: 1 2015 - Wellington Gon?alves Lemos.pdf: 9868472 bytes, checksum: c653096dd1677c18027859c47248be69 (MD5) Previous issue date: 2015-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Currently working with stellar polyhedra in high school is not registered in official national proposals. Such polyhedra arouse interest in teachers and also the students because of its beauty and also for its conceptual struture. Therefore, the presente work aims to analyze how a classroom dedicated to diversity, and not just to students skill limitations, cognitive and contribues differently for learning each of them when the topic studied are the stellar polyhedra. We show you an interactive room is able to include students who easily exclude school due to a difficulty to perform activity with a feature that exposes its limitations. This architeture of classroom challenges educators to rethink different possiblities for analysis of teaching-learning process. In addition to curricular innovations, we believe that the results of the work bring new perspectives for the analysis of mathematical learning through the use of foldings, adjutments, animations and instutional videos / Atualmente o trabalho com poliedros estrelados no ensino m?dio n?o possui registro nas propostas oficiais nacionais. Tais poliedros despertam interesse nos professores, tamb?m nos alunos, devido sua beleza e tamb?m pela sua estrutura conceitual. Assim, o presente trabalho tem o objetivo de analisar como uma sala de aula interativa voltada para a diversidade, e n?o apenas para limita??es de habilidades dos alunos, contribui cognitiva e diferentemente no aprendizado de cada um deles quando o tema estudado s?o os poliedros estrelados. Mostramos como uma sala interativa ? capaz de incluir alunos que facilmente se excluem da aula devido a uma dificuldade apresentada ao realizar atividade com um recurso que exp?e suas limita??es. Essa arquitetura de sala de aula desafia os educadores a repensarem as diferentes possibilidades para an?lise do processo ensino-aprendizagem. Al?m de propor inova??es curriculares, acreditamos que os resultados do trabalho tragam novas perspectivas para a an?lise do aprendizado matem?tico mediante o uso de dobraduras, planifica??es, anima??es e v?deos did?ticos

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-01-20T13:13:06Z No. of bitstreams: 1 2013 - Mauro Meliga Wysard Junior.pdf: 3560905 bytes, checksum: 2826a580c7e2ec9ebe3a9e07daacb4f7 (MD5) / Made available in DSpace on 2017-01-20T13:13:06Z (GMT). No. of bitstreams: 1 2013 - Mauro Meliga Wysard Junior.pdf: 3560905 bytes, checksum: 2826a580c7e2ec9ebe3a9e07daacb4f7 (MD5) Previous issue date: 2013-10-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The need to reduce environmental impacts while maintaining economic efficiency of various processes has motivated research to develop cheaper and sustainable technologies, to replace those already employed in the industrial sectors. Thus, recycling and utilization of natural materials such as coconut fiber or marine animal shells, is envisioned as an alternative to reduce the environmental impact and at the same time the use of these components in industrial processes reduces operational costs. In this context the biosorbents are included, such as coconut fibers and chitosan, which have high applicability to processes for removing metal ions, and are widely available at low cost. In addition, the problem found in the recovery of these adsorbents and adsorbate after the adsorption process can be bypassed by setting biosorbents in polymeric matrixes, obtaining larger parts, which facilitates the separation steps. Thus, this work aims to develop porous composite adsorbent properties, from the physical mixture of maleic anhydride polyethylene (PE-g-MA), coconut fiber (FC), chitosan (Q), and sodium chloride (NaCl) used as porogen agent), and assess the capacity of these new porous composite in the removal of metallic chromium (III) Ion, since this is a residue present in large industrial activities such as electroplating. The porosity of this material was obtained by leaching of NaCl, present in the composition of composite material. For this assessment, we conducted a trial planning, where could be evaluate the influence of particle size of coconut fiber and the amount of chitosan on adsorption process efficiency, as well as the pH of an aqueous solution containing the chromium (III) adsorbate. With the results could be concluded that the model used in planning was valid for the evaluation of the significance of these variables, as well as the trend of better removal of chromium (III), which took place in the higher pH values (between 6 and 7) and in the presence of increased amounts of chitosan (7.5-8.6 g). The granulometric size range of coconut fiber that was more favorable was between 0.097-0.142 mm. Analyzing these porous composites by spectroscopy in the infrared (FTIR), X-ray diffraction (XRD), water absorption and scanning electron microscopy (SEM), you can see and confirm the strong interaction between the components of the mixture, possibly by interfering in the process efficiency of adsorption of chromium / A necessidade de reduzir impactos ambientais e ao mesmo tempo manter a efici?ncia econ?mica de diversos processos, vem motivando o meio acad?mico a realizar pesquisas voltadas para o desenvolvimento de novas tecnologias mais baratas e sustent?veis, que possam substituir as j? empregadas nos setores industriais. Desta forma, a reciclagem e a utiliza??o de mat?rias-primas naturais como a casca de coco e carapa?as de animais marinhos ? vislumbrada como uma alternativa para a redu??o do impacto ambiental, e ao mesmo tempo, pela utiliza??o desses componentes em processos industriais com a finalidade de reduzir custos operacionais. Neste contexto encontram-se os biossorventes naturais, como a fibra de coco e a quitosana, que apresentam alta aplicabilidade em processos de remo??o de ?ons met?licos, e uma grande disponibilidade a baixo custo. Al?m disso, o problema encontrado na recupera??o desses adsorventes e do adsorvato ap?s o processo de adsor??o pode ser contornado pela fixa??o dos biossorventes em matrizes polim?ricas, obtendo-se pe?as de maior volume, o que facilita as etapas de separa??o. Assim, este trabalho teve como objetivo desenvolver comp?sitos porosos com propriedades adsorventes, a partir da mistura f?sica de polietileno graftizado com anidrido maleico (PE-g-MA), fibra de coco (FC), quitosana (Q) e cloreto de s?dio (NaCl) utilizado como agente porog?nico), e avaliar a capacidade de adsor??o desses novos comp?sitos porosos na remo??o do ?on met?lico cromo (III), j? que este, ? um res?duo presente em grandes atividades industriais, como a galvanoplastia. Com esta finalidade, foi realizado um planejamento experimental, onde foi avaliada a influ?ncia do tamanho das part?culas de fibra de coco e da quantidade de quitosana na efici?ncia do processo de adsor??o, assim como o pH da solu??o aquosa contendo o adsorvato cromo (III). Com os resultados pode-se concluir que o modelo usado no planejamento experimental foi v?lido para a avalia??o da signific?ncia dessas vari?veis, como para as melhores condi??es de remo??o do cromo (III), as quais aconteceram nos valores mais elevados de pH (entre 6 e 7) e na presen?a de maiores quantidades de quitosana (7,5-8,6 g). A faixa granulom?trica da fibra de coco que se mostrou mais favor?vel foi de 0,097-0,142 mm. Analisando esses comp?sitos porosos por espectroscopia na regi?o do infravermelho (FTIR), difra??o de raios-X (DRX), absor??o de ?gua e microscopia eletr?nica de varredura (MEV), p?de-se constatar e confirmar a forte intera??o ocorrida entre os componentes da mistura, possivelmente, interferindo na efici?ncia do processo de adsor??o do cromo (III).

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-02-15T12:59:57Z No. of bitstreams: 1 2016 - George William Bravo de Oliveira.pdf: 3064412 bytes, checksum: cc8573a6729fd178716b872c68208cd7 (MD5) / Made available in DSpace on 2017-02-15T12:59:57Z (GMT). No. of bitstreams: 1 2016 - George William Bravo de Oliveira.pdf: 3064412 bytes, checksum: cc8573a6729fd178716b872c68208cd7 (MD5) Previous issue date: 2016-02-24 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES/OBEDUC / The learning process of introductory studies, the orthogonal projective system and constituent elements (point, line and plane), used in Geometry for high school students in technical training courses makes it difficult to develop spatial vision and graphic representation. Learning to see allows the student to understand the formation of projections and return to the practice of observation. Three-dimensional visualization produces recognition of the projected image. The development of this learning cannot be restricted to study based only on programmed handouts with forms or feedback solutions.This Design-Based Research developed and implemented a system of security cameras to aid in visualization. This innovation provided for the construction of an educational experience that fosters collaborative learning through interaction with three-dimensional models of the objects to be represented in graphic drawings. The proposal to investigate the practice of graphic representation and strategies for development of this graphic language was carried out with students, aged between 14 and 17 years, in high school at a state technical school. Data collection was done by the researcher in research logs, activities proposed in class and recordings from security cameras positioned to capture the image ?pura. Results underline the importance of creating an educational process applied to technical drawing that develops the act of the careful observation and integration of objects and images with the main aspects of projective drawing. This enables the learning of the concepts of descriptive geometry and facilitates the visualization of the trihedral system and the design of the principal orthographic views (front, top and side) utilizing varied teaching strategies / O processo de aprendizagem dos estudos introdut?rios, do sistema projetivo ortogonal e de elementos constituintes (ponto, reta e plano), estudados em Geometria Descritiva por alunos do Ensino M?dio de cursos de forma??o t?cnica, encontra dificuldade no desenvolvimento da vis?o espacial e da representa??o gr?fica. Aprender a ver ? uma possibilidade que ? aberta nessa proposta para entendimento da forma??o das proje??es e retomar a pr?tica de observa??o. A visualiza??o em tr?s dimens?es gera reconhecimento da imagem realizada. O desenvolvimento desse aprendizado n?o pode ser restrito ao estudo com base em apostilas programadas com formas ou gabarito de solu??es. Esta ? uma Pesquisa de Desenvolvimento que elaborou e aplicou um sistema de c?meras de seguran?a como aux?lio na visualiza??o. A inova??o valorizou a constru??o de uma experi?ncia de ensino que favore?a o aprendizado de forma colaborativa, e a intera??o com as possibilidades de montagem dos objetos a serem representados e sua representa??o gr?fica. A proposta de investigar a pr?tica da representa??o gr?fica e as estrat?gias para desenvolvimento desta linguagem, foi realizada com estudantes de faixa et?ria entre 14 e 17 anos, do Ensino M?dio em uma escola t?cnica estadual. A coleta de dados foi feita mediante di?rios do pesquisador, de atividades propostas nas aulas e de grava??es provenientes de c?meras de seguran?a posicionadas para captar a imagem da ?pura. Resultados sublinham a import?ncia de cria??o de um processo para a educa??o do olhar aplicado ao desenho t?cnico mediante uma pr?tica que desenvolva o ato de observar. A integra??o com objetos e a gera??o de imagens com os aspectos principais do desenho projetivo. Favorecer o aprendizado dos conceitos de Geometria Descritiva e facilitar a visualiza??o do sistema tri?drico e o desenho das vistas ortogr?ficas principais (vista frontal, superior e lateral) com o uso de estrat?gias did?ticas variadas