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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.
111

Propriedades tribomec?nicas de superf?cies de tit?nio carbonitretadas por plasma

Rocha, Ricardo Cesar da Silva 02 March 2012 (has links)
Made available in DSpace on 2014-12-17T14:07:03Z (GMT). No. of bitstreams: 1 RicardoCSR_DISSERT.pdf: 2528884 bytes, checksum: 9966cb710cbaa37dcf31b5576ecca1d8 (MD5) Previous issue date: 2012-03-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Interstitial compounds of titanium have been mainly studied due to the large range of properties acquired when C, N, O and H atoms are added. In this work, surfaces of TiCxNy were produced by thermochemical treatments assisted by plasma with different proportions of Ar + N2 + CH4 gas mixture. The Ar gas flow was fixed in 4 sccm, varying only N2 and CH4 gas flows. During the thermochemical treatment, the plasma was monitored by Optical Emission Spectroscopy (OES) for the investigation of the influence of active species. After treatments, C and N concentration profile, crystalline and amorphous phases were analyzed by Nuclear Reaction (NRA). Besides tribomechanical properties of the Ti surface were studied through the nanohardness measurements and friction coefficient determination. The worn areas were evaluated by profilometry and Scanning Electronic Microscope (SEM) in order to verify the wear mechanism present in each material. It has been seen which the properties like nanohardness and friction coefficient have strong relation with luminous intensity of species of the plasma, suggesting a using of this characteristic as a parameter of process / Compostos intersticiais de tit?nio t?m sido extensivamente estudados devido ? larga faixa de propriedades adquiridas quando ?tomos de C, N, O e H s?o adicionados. Neste trabalho, superf?cies de TiCxNy foram produzidas por tratamento termoqu?mico auxiliado por plasma de diferentes misturas de N2 + Ar + CH4. Foi fixado o fluxo de Ar em 4 sccm variando-se os fluxos de N2 e CH4. Durante o tratamento termoqu?mico, o plasma foi monitorado por EEO para investiga??o da influ?ncia das esp?cies ativas. Ap?s o tratamento, as superf?cies das amostras foram analisadas quanto ao perfil de concentra??o de C e N, fases cristalinas e fases amorfas. Tamb?m foram analisadas suas propriedades tribomec?nicas atrav?s da medida de nanodureza e da determina??o do coeficiente de atrito. As ?reas desgastadas foram avaliadas por perfilometria e microscopia eletr?nica de varredura (MEV) com o intuito de verificar os mecanismos de desgastes presentes em cada material. Verificouse que propriedades como dureza e coeficiente de atrito variavam com a intensidade das esp?cies, sugerindo o uso da mesma como par?metro de processos a plasma
112

Comportamento mec?nico e tenacidade ? fratura de ligas de alum?nio 2024 e 7075 submetidas a diferentes tempos de envelhecimento

Cavalcante, Felipe Fernandes 06 May 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-26T23:06:54Z No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-08-30T22:45:53Z (GMT) No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) / Made available in DSpace on 2016-08-30T22:45:53Z (GMT). No. of bitstreams: 1 FelipeFernandesCavalcante_DISSERT.pdf: 15830059 bytes, checksum: 1df43f246bc497f6fb2c86ad9f43fb04 (MD5) Previous issue date: 2016-05-06 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Sabe-se que a grande parte das ligas de alum?nio pode sofrer varia??es significativas em suas propriedades mec?nicas dependendo do tratamento de envelhecimento realizado. Por?m, poucos trabalhos apontam as caracter?sticas dessas ligas em condi??es subenvelhecidas e superenvelhecidas, principalmente em rela??o ? tenacidade ? fratura. Al?m disso, estudos recentes apontam que algumas ligas de alum?nio subenvelhecidas podem sofrer uma esp?cie de auto cura, ou seja, esses materiais podem, quando solicitados devido a algum esfor?o externo, tender a um fechamento de algum defeito como uma trinca devido ? precipita??o din?mica, o que aumentaria sua capacidade de resistir ?s solicita??es. Neste contexto, neste trabalho ? avaliada a rela??o entre a tenacidade ? fratura e a resist?ncia ? tra??o e as condi??es de tratamentos t?rmicos de duas ligas de alum?nio (2024-T351 e 7075-T651), tanto na condi??o de entrega quanto submetidas a tratamentos t?rmicos de solubiliza??o (a 480 0C por 2,5 h) e envelhecimento artificial (145 0C por 8, 10, 16 e 24 h para a 7075, e 190 0C por 1, 3, 5, 8 e 12 h para a 2024), portanto, em condi??es de subenvelhecimento (abaixo do m?ximo de dureza), envelhecida (no ponto de m?xima dureza) e superenvelhecimento (al?m do ponto de m?xima dureza). Os materiais, nestas diferentes condi??es de processamento foram caracterizados do ponto de vista mec?nico - atrav?s dos ensaios de tenacidade ? fratura, utilizando a metodologia de entalhe chevron - KICVM (ASTM 1304), de tra??o uniaxial (ASTM E8M) e dureza HRB (ASTM E18) - e do ponto de vista estrutural, atrav?s da microscopia ?ptica, MEV e EDS. As microestruturas obtidas nas diferentes condi??es s?o avaliadas por MEV e DR-X. Os micromecanismos de fratura das amostras de tra??o e tenacidade ? fratura s?o avaliados por MEV. Em rela??o ? dureza verificou-se, para ambas as ligas, que ouve apenas um pequena tend?ncia de redu??o dos valores obtidos para a amostras envelhecidas em rela??o ao estado de entrega. Os resultados dos ensaios de tra??o indicam tamb?m uma pequena redu??o da resist?ncia das amostras envelhecidas, em rela??o ao estado de entrega. Estes resultados de dureza e tra??o indicam que a m?xima resist?ncia pode ser obtida para tratamentos de envelhecimento por 5 h (2024) e entre 10 e 12 h (7075). Os resultados de tenacidade ? fratura mostram que n?o houve influ?ncia significativa dos tempos de envelhecimento de 8h, 10h, 16h e 24h sobre os valores de KICV para a liga 7075, apesar dos tratamentos de envelhecimento terem aumentado a tenacidade ? fratura em rela??o ao estado de entrega. Em rela??o ? liga 2024, nem todos os resultados de tenacidade ? fratura puderam ser validados em fun??o da trajet?ria de crescimento de trinca fora do regime de abertura (modo I), mesmo para corpos de prova de maiores dimens?es. Este resultado indica que os diferentes tratamentos de envelhecimento da liga 2024 atuaram no sentido de aumentar a tenacidade do material, elevando a amplitude dos eventos inel?sticos ? frente da trinca. / Heat treatable aluminum alloys may experience significant changes in mechanical properties depending on heat treatment developed. Futhermore, a few works discuss about this properties in underaged and overaged conditions, mainly about fracture toughness. Recently, some researches showed that some aluminum alloys in underaged conditions may indicate the self healing phenomenon, in other words, when streched mechanically, the material could present a closure, or a reduction in crack growth ratio due local compressive stress associated to dynamic precipitation. In this context, its valued the relationship between fracture toughness, mechanical properties and heat treatment in two aluminum alloys (2024-T351 e 7075-T651) when submitted to solubilization (480 ?C for 2,5h) and artificial aging (145 ?C for 8h, 10h, 12h, 16h and 24h for 2024-S1 named first set and 7075; and 190 ?C for 1h, 3h, 5h, 8h and 12h for 2024-S2, second set), obtaining underaged, peak hardness and overaged conditions. The samples were featured using fracture toughness tests with a chevron notch, K??? (ASTM E1304); tensile tests (ASTM E8/E8M) and Vickers hardness (ASTM E 384). In structural aspects, this alloys were featured using optical microscopy and scanning electron microscopy (SEM), in microstructural aspects, using energy-dispersive X-ray spectroscopy (EDS). The micromechanisms of fracture surface on chevron samples are showed using SEM. After results, hardness and ultimate tensile stress showed maximum values between 3h and 5h (2024-S2) and approximately 10h and 12h (7075). About 2024-S2 alloy, it is showed the phenomenon of dynamic precipitation in delivery state, underaged and peak aged samples, due little peaks on stress-strain curves. However, in 2024 first and second sets, all results cannot be valid because the samples showed a significant change in fracture mode presenting a mix of mode I + mode II, futhermore, thickness B is not sufficient for attend ASTM E 1304. The 7075 aluminum alloy presented a distinguished behavior, showing independence in properties like fracture toughness and hadness mainly in overaged conditions, because as the hardness value increase in this condition, fracture toughness increased also. Besides that, K??? values showed no much variation besides the different times of aging, despite this values are much high than delivery state condition. About micromechanisms of fracture, all conditions presented dimples, and cleavage fracture associated to coarse precipitates.
113

Eugenio Gudin versus Roberto Simonsen: desenvolvimentismo, neoliberalismo e a constru??o do Brasil durante o S?culo XX (1940-70) / Eugenio Gudin versus Robert Simonsen: developmentalism, neoliberalism and Brazil's construction during the twentieth century (1940-70)

Tolentino Neto, Leovigildo Melga?o 04 March 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-08-27T00:23:28Z No. of bitstreams: 1 LeovigildoMelgacoTolentinoNeto_DISSERT.pdf: 932895 bytes, checksum: 215339bf6ea8e7be4ef2d24883c35d90 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-09-02T00:35:08Z (GMT) No. of bitstreams: 1 LeovigildoMelgacoTolentinoNeto_DISSERT.pdf: 932895 bytes, checksum: 215339bf6ea8e7be4ef2d24883c35d90 (MD5) / Made available in DSpace on 2016-09-02T00:35:08Z (GMT). No. of bitstreams: 1 LeovigildoMelgacoTolentinoNeto_DISSERT.pdf: 932895 bytes, checksum: 215339bf6ea8e7be4ef2d24883c35d90 (MD5) Previous issue date: 2016-03-04 / O debate sobre industrializa??o est? arraigado a uma cl?ssica pol?mica dentro da economia, que ganhou f?lego ao longo do s?culo XX: planejamento e intervencionismo, de um lado, versus livre mercado do outro. Essa pesquisa busca reacender o debate sobre industrializa??o tomando como foco a cl?ssica discuss?o acerca do planejamento econ?mico, ocorrida na d?cada de 1940, durante o governo Vargas, entre Eugenio Gudin e Roberto Simonsen. O objetivo ? expor como o pensamento expostos pelos autores foram cruciais na constru??o do desenvolvimento econ?mico do Brasil entre as d?cadas de 1940-1970. A pesquisa utilizou m?todo hist?rico-relativista para analisar criticamente o texto original do debate, por conta do contexto latino-americano sob o qual se o mesmo se desencadeou. A an?lise relativista preconiza uma investiga??o de natureza extensa, isto ?, inclinada ao contexto hist?rico e social sob os quais ocorrem a concep??o de ideias. Os relativistas s?o pesquisadores que nutrem interesses nas rela??es da hist?ria do pensamento econ?mico com o arcabou?o intelectual do autor em quest?o; contrariamente aos ortodoxos schumpeterianos, s?o pesquisadores que nutrem interesses nas rela??es da hist?ria do pensamento econ?mico com o arcabou?o intelectual do autor em quest?o. Os resultados da investiga??o realizada mostram que as ideias defendidas por Simonsen foram as molas propulsoras do desenvolvimento do Brasil ao longo do per?odo estudado, dando base para a edifica??o dos principais planos de desenvolvimento da economia nacional: Plano de Metas, Plano de Acelera??o Econ?mica do Governo (PAEG), I Plano Nacional de Desenvolvimento, II Plano Nacional de Desenvolvimento, al?m da cria??o do Banco Nacional de Desenvolvimento econ?mico (BNDE). / The debate on industrialization is bound to a classic controversy within the economy, which gained momentum during the twentieth century: planning and interventionism on the one hand, versus the free market on the other. This research seeks to rekindle the debate on industrialization taking focused the classic discussion of economic planning, which occurred in the 1940s during the Vargas government, between Eugenio Gudin and Roberto Simonsen. The goal is to expose as thought exposed by the authors were crucial in building the economic development of Brazil between the decades of 1940-1970. The research used historical-relativistic method to review the original text of the debate, on behalf of the Latin American context under which it was unleashed. The relativistic analysis calls for extensive research nature, that is, leaning to the historical and social context in which occur the design ideas. Relativists are researchers who nurture interests in the relations of the history of economic thought with the author's own intellectual framework in question. Relativists, contrary to orthodox Schumpeterian, are researchers who nurture interests in the relations of the history of economic thought with the author's own intellectual framework in question. The results of the research show that the ideas defended by Simonsen were the drivers of development in Brazil over the study period, giving the basis for the building of the main development plans of the national economy: Plan Goals, PAEG, I PND II PND and the creation of BNDE.
114

Figura??es do sujeito no romance de Jos? Saramago e Ant?nio Lobo Antunes / Figurations of the subject in the novels by Jos? Saramago and Ant?nio Lobo Antunes

Oliveira Neto, Pedro Fernandes de 15 February 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-10-11T20:26:15Z No. of bitstreams: 1 PedroFernandesDeOliveiraNeto_TESE.pdf: 2584466 bytes, checksum: 9e347c2e43df7f46c48bb2fb7b9db69d (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-10-13T20:53:57Z (GMT) No. of bitstreams: 1 PedroFernandesDeOliveiraNeto_TESE.pdf: 2584466 bytes, checksum: 9e347c2e43df7f46c48bb2fb7b9db69d (MD5) / Made available in DSpace on 2016-10-13T20:53:57Z (GMT). No. of bitstreams: 1 PedroFernandesDeOliveiraNeto_TESE.pdf: 2584466 bytes, checksum: 9e347c2e43df7f46c48bb2fb7b9db69d (MD5) Previous issue date: 2016-02-15 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Entre as diversas quest?es sobre o sujeito e suas incid?ncias no texto liter?rio, este estudo prefere a de perscrutar acerca de como o tema ? figurado no romance; isto ?, como se constitui e se apresenta entre as aporias do romanesco, que rela??o mant?m com o externo ao texto (a hist?ria, a sociedade), no que interfere na constru??o da narrativa e na forma do romance, quais quest?es suscitam, s?o algumas proposi??es envolvidas numa leitura que compreende Todos os nomes, de Jos? Saramago e N?o entres t?o depressa nessa noite escura, de Ant?nio Lobo Antunes. Esses romances foram elegidos porque se relacionam, respectivamente, a duas das principais correntes da forma romanesca: um mais integrado ao vi?s objetivo e outro ? tradi??o subjetiva. Sem abolir especificidades, mas ciente que essa n?o ? uma rela??o dicot?mica por compreender que o hiato entre as duas formas se resume basicamente a uma maneira de percep??o diversa do romancista sobre a realidade, este estudo se alimenta das duas posi??es no intuito de lidar com especificidades igualmente diversas de figura??o do sujeito no romance. Assim, este estudo dividiu-se nos tr?s momentos ora designados: (1) revisar sobre como o romance tem constru?do uma concep??o de sujeito desde a ruptura mantida com a epopeia. Essa revis?o privilegia tr?s momentos da hist?ria do romance: a epopeia, a verve realista do s?culo XIX e o romance impulsionado pelas novas formas dos anos 1920. Esse exerc?cio ? intermediado pelas leituras de Krysinski (2007), Luc?ks (2009), Z?raffa (2010), Candido (2007), Rosenfeld (1996), Adorno (2003), Benjamin (2012) entre outros; (2) ler Todos os nomes e perscrutar o exerc?cio das personagens centrais do romance - o Sr. Jos?, a mulher desconhecida, o conservador, a senhora do r?s-do-ch?o direito e o espa?o da Conservat?ria por compreend?-la coadjuvante nesse universo; (3) a partir desse mesmo exerc?cio, a leitura de N?o entres t?o depressa nessa noite escura perscruta as figuras de Lu?s Filipe, Margarida, Am?lia, Ana Maria e Maria Clara. Entre as interse??es alcan?adas na rela??o entre as duas obras est? a compreens?o de que o romance se exercita como artefato de conhecimento sobre sujeito e usa a personagem como figura??o sobre suas posi??es ocupadas na contemporaneidade; s?o obras que compreendem a imin?ncia do fim de uma civiliza??o pela forma avariada de coletividade e vida tornada repeti??o invari?vel. E exp?e ao menos duas formas de ruptura dessa condi??o catastr?fica: o sujeito ? a??o e deve sair para o mundo (Jos? Saramago); a desordem n?o apenas social ? individual e o sujeito ? espera enquanto remenda situa??es poss?veis de compreender o est?gio de degrada??o do homem (Ant?nio Lobo Antunes). S?o obras respons?veis por reafirmar o interesse do romance nas exist?ncias mais arredias e silenciosas por entenderem que nelas esconde-se uma capacidade de reanima??o da exist?ncia e ? tarefa do romancista revel?-la. / Among the several questions about the subject and its occurrences in the literary text, the present study intends to search how this theme is represented in the novel; that is, how it is built and represented in the aporias of the romanesque, the relationships it maintains with what is external to the text (history, society), in what it interferes in the narrative construction and in the form of the novel and which questions they arise, are some of the propositions involved in a reading of All the Names, by Jos? Saramago and N?o entres t?o depressa nessa noite escura, by Ant?nio Lobo Antunes. These novels have been chosen because they are related, respectively, to two of the main trends about the form of the novel: one more integrated to an objective view and a second one more integrated to a subjective tradition. Without abolishing the specificities, but aware that the relationship between the subjective and the objective is not a dichotomy because the gap between these two forms is basically the novelist?s distinct way of perception about reality, these two different positions are considered in order to deal with equally diverse specificities of the figuration of the subject in the novel. Thus, this thesis is divided in three following parts: (1) a review of how the novel has built a conception of subject since the rupture with the epic. This review privileges three different moments in the history of the novel: the epic, the realist verve of the 19th Century and the novel moved by the 1920s new forms. This exercise is helped by the readings of Krysinski (2007), Luc?ks (2009), Z?raffa (2010), Candido (2007), Rosenfeld (1996), Adorno (2003), Benjamin (2012) among others; (2) reading All the Names and peering into the main characters of the novel ? Senhor Jos?, the unknown woman, the registrar, the right ground floor lady and the space of the Central Registry that is taken as a support in this universe; (3) considering the aforementioned exercise, the reading of N?o entres t?o depressa nessa noite escura peers into the characters Lu?s Filipe, Margarida, Am?lia, Ana Maria e Maria Clara. Among the intersections between the two books, there is the understanding that the novel is an artifact of knowledge about the subject as a figuration of its positions occupied in the contemporary world; both books understand the imminent end of a civilization by the damaged collectivity and life becoming invariable repetition. At least two other different means of rupture with this catastrophic condition are exposed: the subject is action and has to face the world (Jos? Saramago); the non-exclusively social disarray is individual and the subject is the waiting while he mends the possible situations to understand human degradation (Ant?nio Lobo Antunes). Both books are responsible for reaffirming the interest of the novel in the most reluctant and silent existences, once they understand these existences hide an ability of reanimation whose revelation is a task of the novelist.
115

N?veis de prote?na bruta e de concentrado em dietas para cordeiros / Levels of crude protein and concentrate in diets for lambs

Santos, Regina Silva 18 July 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T15:55:10Z No. of bitstreams: 2 regina_silva_santos.pdf: 994226 bytes, checksum: 2d65c8a318f4c25b5c82de13adb8fbad (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T15:56:19Z (GMT) No. of bitstreams: 2 regina_silva_santos.pdf: 994226 bytes, checksum: 2d65c8a318f4c25b5c82de13adb8fbad (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-05T15:56:37Z (GMT) No. of bitstreams: 2 regina_silva_santos.pdf: 994226 bytes, checksum: 2d65c8a318f4c25b5c82de13adb8fbad (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-01-05T15:56:37Z (GMT). No. of bitstreams: 2 regina_silva_santos.pdf: 994226 bytes, checksum: 2d65c8a318f4c25b5c82de13adb8fbad (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2013 / Foram conduzidos dois experimentos para avaliar o efeito de dietas, contendo dois n?veis de prote?na bruta e de concentrado sobre o consumo e a digestibilidade aparente total dos nutrientes, o balan?o de nitrog?nio (BN), o pH, a concentra??o de nitrog?nio amoniacal (N-NH3) no r?men, a efici?ncia microbiana e o desempenho em cordeiros. As dietas consistiram de 10,0 e 14,25% de prote?na bruta (PB) e de 40 e 60% de concentrado (CONC), utilizando-se a silagem de milho como volumoso. No ensaio de digestibilidade, foram utilizados quatro cordeiros machos, n?o castrados, F1 Santa In?s x Texel desmamados, com peso vivo m?dio de 21 kg, fistulados no r?men e distribu?dos em quadrado latino 4 x 4, com quatro animais, quatro dietas e quatro per?odos. Cada per?odo experimental teve dura??o de 15 dias, sendo nove dias para adapta??o e seis para coletas. Houve efeito da intera??o tripla (PBxCONCxTempo) sobre os teores de nitrog?nio amoniacal ruminal, enquanto o pH n?o foi afetado. N?o houve efeito da intera??o PB x CONC sobre as vari?veis estudadas. Houve efeito de n?veis de PB sobre o consumo e a digestibildade de PB, bem como, sobre as quantidades de N ingerido, absorvido, urin?rio e retido (BN) e sobre as excre??es de ?cido ?rico. No ensaio de desempenho, foram utilizados 30 cordeiros F1 Santa In?s x Texel, n?o castrados, com peso vivo m?dio de 19 kg, distribu?dos em esquema fatorial 2x2, no delineamento em blocos casualizados, com quatro dietas e oito repeti??es. Al?m desses, mais quatro cordeiros foram abatidos no in?cio da fase experimental, representando os animais refer?ncia. Houve efeito da intera??o de n?veis de PB e de concentrado para os consumos de EE, FDNcp e CNF. Houve efeito de n?veis de PB sobre os consumos de MS, MO, PB, FDNcp, NDT, PDR e PNDR, o GMD, GCPCJ e a CA. Houve efeito dos n?veis de concentrado sobre os consumos de MS, MO, PB, CNF e NDT e sobre GMD, GCPCJ, GCPCJ/GMD e CA. Conclui-se que, dietas com n?vel mais alto de PB ou de concentrado, proporcionam mais alto consumo de nutrientes e melhor desempenho animal. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT Two essays were performed in order to evaluate the effects of diets containing two levels of crude protein and concentrate on the consumption, the total apparent digestibility of the nutrients, the nitrogen balance, the pH, the N-NH3 concentration in the rumen, the microbial efficiency and the performance in lambs. The diets consisted of 10,0 and 14,25% crude protein (CP) and 40 and 60% concentrate, using corn silage as forage. In the digestibility essay, four male lambs were used. The animals were not castrated, F1 Santa In?s x Texel, weaned, rumen fistulated, presented an average live weight of 21 kg and were distributed in Latin square 4 x 4, with four diets and four periods. Each experimental period lasted 15 days, being nine of it for adaptation and six for the collections. Triple interaction (CP x CONC x Time) acted on the ruminal ammonia nitrogen contents, while the pH was not affected. The interaction between CP x CONC had no effect on the studied variables. The CP levels presented an effect on the consumption and the PB digestibility, as for the amounts of ingested, absorbed and urinary nitrogen and for the uric acid excretions. In the performance essays, 30 ?F1 Santa In?s x Texel? castrated lambs were used, presenting an average live weight of 19 kg and distributed in the randomized block design using four treatments and eight replicates. Beside these lambs, other four were slaughtered in the beginning of the experimental phase, representing the reference animals. The PB and the concentrate levels interaction affected the EE, NDFap and NFC consumption. The CP levels also affected the DM, OM, CP, NDFap, TDN, RDP and RUP, ADG, CGBWF and FC consumption. The concentrate levels affected DM, OM, CP, NFCap and TDN and also ADG, CGBWF, GCBWF/ADG and FC replicates. So, we conclude the crude protein and concentrate levels do not affect the nutrients consumption and digestibility, except for the crude protein which is higher in a diet with high protein levels, that also provide higher nitrogen balance values, N-NH3 concentrations and uric acid excretions. The diets containing 14,25% PB or 60% concentrate promote higher nutrients consumptions and better lambs performances.
116

Consumo, digestibilidade e desempenho de ovinos alimentados com casca de maracuj? desidratada / Intake, digestibility and performance of sheep fed with dried passion fruit peel

Sena, Janaina Adna Barbosa 26 September 2011 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T16:55:54Z No. of bitstreams: 2 janaina_adna_barbosa_sena.pdf: 803348 bytes, checksum: 7fcbe004c490cd56b913efb2969519b6 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T16:56:20Z (GMT) No. of bitstreams: 2 janaina_adna_barbosa_sena.pdf: 803348 bytes, checksum: 7fcbe004c490cd56b913efb2969519b6 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-11-18T16:56:20Z (GMT). No. of bitstreams: 2 janaina_adna_barbosa_sena.pdf: 803348 bytes, checksum: 7fcbe004c490cd56b913efb2969519b6 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2011-09-26 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / O experimento foi conduzido no Campus Experimental Moura, no Laborat?rio de Ruminantes do Departamento de Zootecnia da Universidade Federal dos Vales do Jequitinhonha e Mucuri ? Curvelo, MG. Foram utilizados para o ensaio de digestibilidade 12 ovinos, machos mesti?os Santa In?s, alimentados com quatro dietas totais, com diferentes n?veis de substitui??o do feno de Tifton 85 pelo res?duo de maracuj?: 0% (controle); 20%; 40% e 60% de substitui??o. Avaliou-se o consumo e fez-se coleta total de fezes e urina, com devidas amostragens para posteriores an?lises. O delineamento utilizado foi o DIC, com peso inicial como covari?vel. O consumo de nutrientes n?o foi influenciado pelos n?veis de substitui??o. ? exce??o da FDN, n?o houve diferen?a significativa para a digestibilidade aparente dos nutrientes, bem como para o balan?o de nitrog?nio. Para o ensaio de desempenho foram utilizados 20 animais, machos mesti?os Santa In?s, confinados. Os mesmos tratamentos foram testados. Ra??es fornecidas e sobras foram amostradas para an?lises. Pesagens foram realizadas semanalmente para avaliar o ganho de peso. Ao final de 63 dias de confinamento avaliou-se as medidas biom?tricas e os animais foram abatidos. Avaliou-se ent?o, pesos e rendimentos de carca?a, e os componentes n?o-carca?a. O delineamento utilizado foi blocos casualizados, sendo as m?dias submetidas ? an?lise de regress?o pelo PROC GLM do programa estat?stico SAS (SAS, 2002). Os consumos de MS e PB foram influenciados pelos tratamentos, com superioridade para o n?vel de 40% de substitui??o; assim como os ganhos em peso. Para os rendimentos de carca?a os melhores resultados foram registrados para 60% de substitui??o. Para a an?lise de cortes e medidas biom?tricas apenas a paleta e a circunfer?ncia de t?rax diferiram, assim como r?men/ret?culo, omaso e intestino delgado para os componentes n?o-carca?a. Recomenda-se a substitui??o do feno pelo res?duo de maracuj? quando houver redu??o no custo da dieta. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2011. / ABSTRACT The experiment was conducted at Moura?s Experimental Campus, in the Laboratory of Ruminants, Department of Animal Science, University of the Jequitinhonha and Mucuri, in the town of Curvelo, Minas Gerais state, Brazil. There had been used for the digestibility trial 12 sheep, Santa Inez crossbred males fed with four diets in total, with different levels of substitution of Tifton 85 hay by the residue of passion fruit: 0% (control), 20%, 40% and 60% replacements. Consumption was evaluated and there was a total collection of feces and urine, with appropriate samples for further analysis. The experimental design was randomized with initial weight as covariate. The nutrient intake was not influenced by levels of substitution. With the exception of the NDF, there was no significant difference in the apparent digestibility of nutrients, or with nitrogen balance. For the performance test were used 20 confined animals, male crossbred Santa In?s. The same treatments were tested. Rations were supplied and sampled for analysis. Weight measurements were performed weekly to assess weight gain. At the end of 63 days of confinement was evaluated biometric measurements and the animals were slaughtered. Therefore, there have been analyzed, weights and carcass, and non-housing components. The experimental design was randomized blocks, and the means subjected to regression analysis using PROC GLM of SAS statistical software (SAS, 2002). The intake of DM and CP were influenced by treatments with high values to the level of 40% substitution, as well as gains in weight. For carcass yield the best results were recorded for 60% substitution. For analysis of cuts and biometric measures only the palette and chest circumference differed, as well as rumen/reticulum, omasum and small intestine for non-housing components. It is recommended to replace the hay residue of passion when there is a reduction in the cost of the diet
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N?veis de prote?na degrad?vel no r?men em dietas para cordeiros / Levels of rumen degradable protein in diets for lambs

Silva, Janaina de Lima 25 June 2010 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T18:04:13Z No. of bitstreams: 2 janaina_lima_silva.pdf: 2943351 bytes, checksum: eedd3d2b236bb813951c76f45384d9d9 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-11-18T18:04:38Z (GMT) No. of bitstreams: 2 janaina_lima_silva.pdf: 2943351 bytes, checksum: eedd3d2b236bb813951c76f45384d9d9 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) / Made available in DSpace on 2015-11-18T18:04:38Z (GMT). No. of bitstreams: 2 janaina_lima_silva.pdf: 2943351 bytes, checksum: eedd3d2b236bb813951c76f45384d9d9 (MD5) license_rdf: 23898 bytes, checksum: e363e809996cf46ada20da1accfcd9c7 (MD5) Previous issue date: 2010 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / Foram conduzidos dois experimentos para avaliar o efeito de dietas com diferentes n?veis de prote?na degrad?vel no r?men (PDR) sobre o consumo, a digestibilidade aparente total dos nutrientes, o balan?o de nitrog?nio e o desempenho em cordeiros. As dietas consistiram de quatro n?veis de PDR (9,15; 9,97; 10,79 e 11,61% na MS), correspondentes a 14,25; 15,50; 16,75 e 18,00% de PB, com 40% de silagem de milho e 60% de concentrado, na base da mat?ria seca. No ensaio de digestibilidade e balan?o de nitrog?nio foram utilizados oito cordeiros machos inteiros da ra?a Santa In?s, com peso vivo m?dio de 26,9 e 24,7 kg, distribu?dos em dois quadrados latinos 4 x 4. Cada per?odo experimental teve a dura??o de 15 dias, sendo 10 para adapta??o e cinco para coletas. Os animais foram mantidos em gaiolas metab?licas individuais, usando-se sacolas para coleta total de fezes, para fins de c?lculos dos coeficientes de digestibilidade in vivo. A coleta de urina foi realizada durante 24 horas, utilizando-se baldes pl?sticos cobertos com telas, quando mediu-se o volume da quantidade excretada nesse per?odo. N?o houve efeito de n?veis crescentes de PDR sobre os consumos de nutrientes, exceto de PDR. As digestibilidades aparentes totais dos nutrientes, bem como o balan?o de nitrog?nio, tamb?m n?o foram influenciadas pelos n?veis de PDR. No ensaio de desempenho foram utilizados 31 cordeiros machos inteiros da ra?a Santa In?s, com peso vivo m?dio de 22,0 kg, distribu?dos no delineamento inteiramente casualizado, com quatro tratamentos (9,15 a 11,61% de PDR na MS), tr?s com oito repeti??es e um com sete repeti??es. Al?m desses animais, mais quatro foram abatidos no in?cio da fase experimental, representando os animais-refer?ncia na metodologia do abate comparativo. N?o houve efeito de n?veis crescentes de PDR sobre os consumos de nutrientes, exceto de PB, PDR e PNDR, bem como para o peso vivo ao abate, ganho de peso total, ganho m?dio di?rio, convers?o alimentar e caracter?sticas de carca?a (peso, ganho e rendimento). Conclui-se que os n?veis de PDR, de 9,15 a 11,61% na MS das dietas, n?o alteram o consumo de nutrientes, exceto de PB, PDR e PNDR, nem a digestibilidade aparente total dos nutrientes, o balan?o de nitrog?nio e o desempenho de cordeiros. Assim, pode-se recomendar a utiliza??o do n?vel mais baixo de PDR (9,15% na MS, com 14,25% de PB), contribuindo para a redu??o da excre??o de nitrog?nio no ambiente e de custos no sistema de produ??o. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2010. / ABSTRACT Two experiments were conducted to evaluate the effect of diets with different levels of rumen degradable protein (RDP) on the intake, total apparent digestibility of nutrients, nitrogen balance and performance in lambs. Diets consisted of four levels of RDP (9.15, 9.97, 10.79 and 11.61% in DM), corresponding to 14.25, 15.50, 16.75 and 18.00% CP, with 40% corn silage and 60% concentrated on dry matter basis. In the digestibility trial and nitrogen balance were used eight Santa In?s lambs, with average weight of 26.9 and 24.7 kg divided into two 4 x 4 latin squares. Each experimental period lasted 15 days, considering 10 for adaptation and five for collections. The animals were kept in individual metabolic cages, using bags for total fecal collection for purposes of calculating the digestibility in vivo. The urine collection was performed during 24 hours, using plastic buckets covered with canvas, when the volume of the amount excreted in this period was measured. There was no effect of increasing levels of RDP on the nutrients intake, except for RDP. The apparent digestibilities of nutrients and nitrogen balance were also not influenced by levels of RDP. In the performance test were used 31 male Santa In?s lambs, with average weight of 22.0 kg, allotted in a completely randomized design with four treatments (9.15 to 11.61% RDP in DM), three with eight and one with seven replicates. Besides these animals, four were slaughtered in the early experimental stage, representing the reference animals in the methodology of comparative slaughter. There was no effect of increasing levels of RDP on intake of nutrients, except for CP, RDP and RUP as well as the slaughter live weight, total weight gain, average daily gain, feed conversion and carcass traits (weight, gain and yield). We conclude that levels of RDP, from 9.15 to 11.61% in DM of diets, do not alter nutrient intake, except for CP, RDP and RUP nor the total apparent digestibility of nutrients, nitrogen balance and lambs performance. Thus, we can recommend the use of the lower level of RDP (9.15% DM, with 14.25% CP), contributing to the reduction of nitrogen excretion in the environment and of costs in the production system.
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Adsor??o e dessor??o das esp?cies de ars?nio (III e V) e ?cido monometilars?nico, pela K-jarosita, para proposta de remedia??o ambiental

Hott, Rodrigo de Carvalho January 2016 (has links)
Data de aprova??o ausente. / ?rea de concentra??o: Qu?mica Anal?tica. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2016-12-21T17:35:27Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) rodrigo_carvalho_hott.pdf: 1415995 bytes, checksum: f0a923f5addbb9b380763851a41b99e6 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-01-31T13:51:38Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) rodrigo_carvalho_hott.pdf: 1415995 bytes, checksum: f0a923f5addbb9b380763851a41b99e6 (MD5) / Made available in DSpace on 2017-01-31T13:51:38Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) rodrigo_carvalho_hott.pdf: 1415995 bytes, checksum: f0a923f5addbb9b380763851a41b99e6 (MD5) Previous issue date: 2016 / A elevada toxicidade e potencial de acumula??o de ars?nio em diversos ambientes t?m incentivado pesquisas de novos m?todos de remo??o desse ?on em ?guas contaminadas. Dentre os diversos processos utilizados, a adsor??o contendo ?xidos de ferro tem apresentado bons resultados na remedia??o de ambientes aqu?ticos contaminados por ars?nio. Entretanto, muito do ars?nio liberado no ambiente aqu?tico ? proveniente de efluentes de minera??o, que apresenta meio extremamente ?cido, o que impossibilita a a??o da maioria dos adsorventes utilizados. Neste contexto, a K-jarosita surge como alternativa na remo??o de ars?nio em ambientes contaminados devido sua estabilidade neste ?mbito de baixo pH. Os estudos deste trabalho foram realizados no campus do Mucuri da UFVJM e tiveram como objetivo sintetizar, caracterizar e avaliar atrav?s de ensaios de adsor??o a efetividade de nanopart?culas de k-jarosita na remo??o de ars?nio inorg?nico (III e V) e ars?nio org?nico (?cido monometilars?nico-MMA) em ?gua contaminada, bem como a dessor??o destes elementos promovendo a libera??o dos s?tios de adsor??o dos nanomateriais. A K-jarosita foi caracterizada atrav?s da difratometria de raios-X, com seus pontos de reflex?o estando de acordo com o arquivo padr?o JCPDS 36-427. Seus dados difratom?tricos foram refinados pelo m?todo de Rietveld, caracterizando sua estrutura como rombo?drica de densidade 3,045g cm-3. Apresenta uma ?rea superficial de 9 m2 determinada atrav?s do m?todo BET, sendo uma estrutura mesoporosa, com poros apresentando volume de 0,034 cm3 g-1 e tamanho m?dio de 90?, determinados pelo m?todo BJH. Nos testes de adsor??o, os estudos cin?ticos demonstraram que a K-jarosita apresenta uma r?pida adsor??o, tendo o As(V) sido mais adsorvido que os demais. Com rela??o ao efeito de competi??o de ?nions, foram realizados ensaios com NO3-, PO43- e SO42-, sendo observada pouca interfer?ncia dos ?ons nitrato e fosfato, e um efeito de aumento de adsor??o do ?on sulfato com rela??o ao As (V). No caso do pH, foram avaliadas as faixas de pH do meio ?cido ao meio alcalino, sendo que nestas foi verificada maior estabilidade da K-jarosita em pH pr?ximo de 3, fora do qual ocorre sua desestabiliza??o com forma??o de outros ?xidos de ferro. A dessor??o ocorre em pH acima de 12, sendo o As-i (V) e o As-o MMA os mais facilmente liberados. Foram avaliadas isotermas de Langmuir, Freundlich, Langmuir-Freundlich e Redlich-Peterson, sendo todas adequadas ? adsor??o de ars?nio pela K-jarosita, tendo o modelo de Langmuir-Freundlich apresentado um melhor ajuste. A capacidade m?xima de adsor??o pelas nanopart?culas de K-jarosita foi de 11,12 mg g-1 para As (III), de 18,26 mg g-1 para As (V) e de 13,35 mg g-1 para MMA. Em an?lise de amostras de ?guas superficiais de rios contaminados por ars?nio, provenientes do munic?pio de Paracatu/MG, todas ficaram ap?s a adsor??o por K-jarosita abaixo dos limites estabelecidos pela legisla??o vigente. Foi realizada tamb?m a recupera??o do ars?nio ap?s dessor??o na forma de Ag3AsO4, o qual apresentou grande efici?ncia em ensaios de fotocat?lise, que tamb?m foram realizados. E como forma de funcionalizar o uso das nanopart?culas de K-jarosita, foram desenvolvidos prot?tipos de filtros que apresentaram grande efici?ncia na remo??o do ars?nio em amostras de ?gua. Atrav?s deste estudo, foi poss?vel verificar que a K-jarosita apresenta grande potencial de ser utilizada como forma de remedia??o ambiental em ambientes aquosos contaminados por ars?nio. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, [2016]. / The high toxicity and potential of arsenic accumulation in different environments have encouraged works of new ion removal methods in contaminated water. Among the various processes used, the adsorption containing iron oxides has shown good results in the remediation of aquatic environments contaminated by arsenic. However, much of the arsenic is released into the aquatic environment from mining waste, which presents extremely acid medium, which prevents the action of most adsorbents used. In this context, the K-jarosite is an alternative in the removal of arsenic in contaminated environments due to its stability in the context of low pH. Studies of this work were carried out in the Mucuri campus from UFVJM and aimed to synthesize, characterize and evaluate through adsorption tests the effectiveness of K-jarosite nanoparticles in inorganic arsenic removal (III and V) and organic arsenic (monometilars?nic acid -MMA) in contaminated water and desorption of these elements promoting the release of nanomaterials adsorption sites. The K-jarosite was characterized by diffraction of X-rays, with their reflection points are in accordance with the standard file JCPDS 36-427. Its difratom?trics data were refined by the Rietveld method, characterizing its structure and density of rhombohedral 3,045g cm-3. Having a surface area of 9 m2 determined by the BET method, being a mesoporous structure with pores having volume of 0.034 cm3 g-1 and 90 ? average size determined by the BJH method. In adsorption tests, kinetic studies have shown that K-jarosite has a rapid adsorption, and the As (V) was adsorbed more than the others. With respect to anions competition effect, tests were performed with NO3-, PO43- and SO42-, and observed little interference of nitrate and phosphate ions, and sulfate ion adsorption increased effect with respect to As (V). In the case of pH, the pH ranges from acid to alkaline medium were evaluated, and these were verified increased stability of K-jarosite at pH around 3, out of which a destabilization occurs with formation of other iron oxides. The desorption occurs at pH above 12 and the As-i (V) and o-MMA to more easily released. Langmuir isotherms were evaluated, Freundlich, Langmuir-Freundlich and Redlich-Peterson, all being suitable for the adsorption of arsenic by K-jarosite having the model of Langmuir-Freundlich presented a better fit. The maximum adsorption capacity for K-jarosite nanoparticles was 11.12 mg g-1 for As (III) 18.26 mg g-1 to As (V) and 13.35 mg g-1 for MMA . In analysis of surface water samples from contaminated rivers by arsenic, from the Paracatu city / MG, all they were after adsorption by K-jarosite below the limits established by law. It also performed the recovery of arsenic desorbed in the form of Ag3AsO4, which showed great efficiency in photocatalysis tests were also performed. And as a way to functionalize the use of K-jarosite nanoparticles filter prototypes were developed that showed high efficiency in the removal of arsenic in water samples. Through this study, we found that K-jarosite has potential to be used as a form of environmental remediation in aqueous environments contaminated by arsenic.
119

Hematitas nanoparticuladas como fotocatalisadores potenciais para degrada??o qu?mica de contaminantes org?nicos em meio aquoso e a produ??o de hidrog?nio por fragmenta??o molecular da ?gua e da am?nia

Melo, Edilailsa Janu?rio de 22 February 2017 (has links)
Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2017-06-02T22:41:13Z No. of bitstreams: 2 edilailsa_januario_melo.pdf: 2845467 bytes, checksum: 55f2a32335b696129bb30309f301b7ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2017-06-22T12:28:16Z (GMT) No. of bitstreams: 2 edilailsa_januario_melo.pdf: 2845467 bytes, checksum: 55f2a32335b696129bb30309f301b7ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) / Made available in DSpace on 2017-06-22T12:28:16Z (GMT). No. of bitstreams: 2 edilailsa_januario_melo.pdf: 2845467 bytes, checksum: 55f2a32335b696129bb30309f301b7ee (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O desenvolvimento de novos semicondutores fotocatalisadores, em particular os ativos na produ??o de hidrog?nio por fragmenta??o molecular da ?gua e da am?nia (presente no lixiviado de biodigestores ou de aterros sanit?rios e em efluentes industriais), tem dominado a ordem priorit?ria de interesse nas tecnologias avan?adas para a gera??o de energia limpa. Este trabalho teve como objetivo principal avaliar a produ??o fotocatalisada de hidrog?nio gasoso, a partir da fragmenta??o molecular da ?gua ou da am?nia, por uso da hematita pura ou da hematita dopada com os c?tions met?licos cobalto, n?quel, cobre e zinco como materiais semicondutores. Os materiais preparados por coprecipita??o foram caracterizados pelas t?cnicas de EDX, MEV, DRX, espectroscopia M?ssbauer, FTIR, BET e XPS. A taxa da produ??o de hidrog?nio foi avaliada por medidas de densidade da corrente gerada pelo H2(g) evolu?do da fragmenta??o molecular da ?gua ou da am?nia, em c?lula fotoeletroqu?mica (PEC). Foram tamb?m realizados testes fotocatal?ticos, sob luz vis?vel, com as hematitas, pura e com dopantes, como fotocatalisadores para degrada??o do corante ?ndigo de carmim, utilizado como mol?cula modelo, simulando a decomposi??o de substrato org?nico poluente em ?gua presente em efluentes industriais. Os resultados dos testes de degrada??o do corante mostraram que as hematitas dopadas com cobre e zinco tiveram relativamente alta atividade na degrada??o do corante; os melhores resultados foram obtidos com a hematita com zinco. Na evolu??o do hidrog?nio da fotocat?lise da ?gua, a dopagem com c?tions met?licos n?o alterou significativamente a atividade fotoeletroqu?mica da hematita. Ainda assim, a amostra de hematita dopada com n?quel foi a que apresentou um discreto aumento da densidade de corrente, maior propor??o de hidrog?nio gasoso produzido, sob radia??o com comprimento de onda maior do que 450 nm. A densidade de corrente gerada da degrada??o da am?nia foi maior, se comparada ? fragmenta??o da ?gua. No entanto, a dopagem tamb?m n?o alterou de forma significativa a atividade PEC dos materiais. Das amostras de hematitas dopadas, a com cobre foi a que apresentou os melhores resultados fotoeletroqu?micos, ainda que abaixo da efici?ncia fotoeletroqu?mica da hematita pura. / Disserta??o (Mestrado) ? Programa de P?s-gradua??o em Biocombust?veis, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / Technological developments of semiconductors to be used as photocatalysts for hydrogen production and for the degradation of organic pollutants in water in different circumstances, such as ammonia sluggishness from biodigesters and organic residues from industrial effluents, are strongly challenging the interest of the scientific community. The main objective of this work was to evaluate the molecular hydrogen production from the molecular fragmentation of water and ammonia using pure hematite and cobalt, nickel copper and zinc dopant prepared as co-precipitators as semiconductor materials. The materials prepared were characterized by EDX, MEV, XRD, M?ssbauer, FTIR, BET and XPS spectroscopy. The evaluation of the hydrogen production was carried out through measurements of current densities generated by the decomposition of water and ammonia in a photoelectrochemical cell (PEC). Photocatalytic tests were also carried out under visible light using pure hematite and with dopants as photocatalysts for the degradation of carmine indigo dye used as a model molecule. The results of the dye degradation tests showed that copper and zinc doped hematite increased dye degradation, and the best results were obtained for zinc hematite. In the evolution of hydrogen from water, the doping with metallic cations did not significantly alter photoelectrochemical activity of hematite, the hematite with nickel was the sample that presented a small increase in current density when in the presence of light. The current density generated by the ammonia degradation and consequent hydrogen production was higher when compared to water, however, doping also did not significantly alter the PEC activity of the materials, comparing the materials, the hematite with copper was the sample that presented the best results.
120

?Vou te proteger?: a Educa??o Patrimonial como estrat?gia para prote??o e valoriza??o do patrim?nio arqueol?gico do munic?pio de Fel?cio dos Santos, MG.

Macedo, Thaisa Dayanne Almeida 30 June 2017 (has links)
O orientador mencionado na lista da Folha de Aprova??o, conforme consta na vers?o impressa do trabalho. / ?rea de concentra??o: Ci?ncias Humanas. / Linha de pesquisa: Hist?ria, Cultura e Arqueologia. / Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2018-04-03T12:42:01Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaisa_dayanne_almeida_macedo.pdf: 7456673 bytes, checksum: 29c01cd6e85ebd015aad3c40037a4528 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2018-04-09T17:15:11Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaisa_dayanne_almeida_macedo.pdf: 7456673 bytes, checksum: 29c01cd6e85ebd015aad3c40037a4528 (MD5) / Made available in DSpace on 2018-04-09T17:15:11Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) thaisa_dayanne_almeida_macedo.pdf: 7456673 bytes, checksum: 29c01cd6e85ebd015aad3c40037a4528 (MD5) Previous issue date: 2017 / Universidade Federal dos Vales do Jequitinhonha e Mucuri (UFVJM) / Este trabalho tem como por finalidade relatar as experi?ncias as reflex?es decorrentes de uma experi?ncia de Educa??o Patrimonial realizada na cidade de Fel?cio dos Santos- MG. Parte-se do princ?pio de que mais do que um conjunto de conceitos, a Educa??o Patrimonial apresenta-se como base de conhecimento capaz de gerar nos indiv?duos a no??o de cidadania, voltada para a necessidade de sensibilizar acerca do patrim?nio (material e imaterial). O estabelecimento de metodologias e pr?ticas que cooperam para a valoriza??o e apropria??o do patrim?nio arqueol?gico ? significativamente importante para a valoriza??o e preserva??o dos bens culturais e das mem?rias e narrativas interligadas a eles. Pois, trata-se de tentar compreender o olhar das comunidades perante as identidades e hist?rias do seu pr?prio lugar e com as express?es culturais em torno delas. Nesse sentido, a pesquisa aqui apresentada se fundamenta na diversidade das mem?rias e nas multiplicidades de hist?rias, contos e causos, como pressuposto para criar aproxima??es entre o conhecimento cient?fico e a comunidade. Possui como foco principal uma regi?o que por algum tempo tem sido local de desenvolvimento de pesquisas no campo da arqueologia pelo Laborat?rio de Arqueologia e Estudo da Paisagem (LAEP/CEGEO/UFVJM). Almeja-se, assim, a constru??o metodologias e pr?ticas que possam dar significados sociais e culturais aos vest?gios arqueol?gicos e hist?ricos, possibilitando ?s comunidades detentoras deste patrim?nio a compreens?o da import?ncia da prote??o, valoriza??o e respeito (sobre) do patrim?nio hist?rico, arqueol?gico e cultural. Considera-se a Arqueologia P?blica como um aparato adequado para ser utilizado neste tipo de estudo, uma vez que, em seus princ?pios valoriza envolvimento do p?blico, em uma constru??o do conhecimento cient?fico atrav?s da interface entre Arqueologia-Sociedade. Dessa forma, o desejo por conhecer e divulgar o patrim?nio cultural da cidade acabou por colocar o p?blico envolvido como sujeitos fundamentais para os objetivos por n?s tra?ados. Cabe salientar que antes de tudo, a pesquisa nos revelou que h? um universo imerso nas comunidades que precisa ser conhecido. E que conhecer esse universo ? uma responsabilidade social reservada aos pesquisadores e profissionais que aventuram atr?s de descobertas naquelas terras. / Disserta??o (Mestrado Profissional) ? Programa de P?s-Gradua??o em Ci?ncias Humanas, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2017. / This work aims to report the experiences of the reflections resulting from a Heritage Education experience held in the city of Fel?cio dos Santos - MG. It is assumed that more than one set of concepts, Heritage Education presents itself as a knowledge base capable of creating in individuals the notion of citizenship, focused on the need to raise awareness about the heritage (material and immaterial). The establishment of methodologies and practices that cooperate for the valorization and appropriation of the archaeological heritage is significantly important for the valuation and preservation of the cultural assets and of the memories and narratives interconnected to them. It tries to understand the community's view of the identities and histories of their own place and the cultural expressions around them. In this sense, the research presented here focuses on the diversity of the memories and on the multiplicities of stories, oral and non-oral. All of them are seen as a presupposition to create approximations between scientific knowledge and the community. It has as main focus a region which for some time has been a place of research development in the field of archeology by the Laboratory of Archeology and Landscape Studies (LAEP / CEGEO / UFVJM). It is hoped, therefore, to construct methodologies and practices that can give social and cultural meanings to the archaeological and historical vestiges. It will enable the communities that hold this patrimony to understand the importance of protection, valorization and respect (about) the historical, archaeological, and cultural patrimony. Public archeology is considered as a suitable apparatus to be used in this type of study, since, in its principles it values public involvement in a construction of scientific knowledge through the interface between Archeology and Society. In this way, the desire of knowing and divulging the cultural heritage of the city ended up putting the public involved as fundamental subjects for the goals we have set. It should be noted that, first of all, this research has revealed to us that there is a universe immersed in the communities that needs to be known. And that knowing this universe it is a social responsibility reserved for researchers and professionals who venture behind discoveries in those lands.

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