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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.
1

Low cement structural lightweight concrete with optimized multiple waste mix design / Concreto leve estrutural de baixo consumo de cimento com misturas otimizadas de res?duos

Sampaio, Zodinio Laurisa Monteiro 25 April 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-11-22T20:18:43Z No. of bitstreams: 1 ZodinioLaurisaMonteiroSampaio_TESE.pdf: 4245538 bytes, checksum: 687e089323cb706bdb8dc70fe1aa7593 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-11-23T00:28:27Z (GMT) No. of bitstreams: 1 ZodinioLaurisaMonteiroSampaio_TESE.pdf: 4245538 bytes, checksum: 687e089323cb706bdb8dc70fe1aa7593 (MD5) / Made available in DSpace on 2017-11-23T00:28:27Z (GMT). No. of bitstreams: 1 ZodinioLaurisaMonteiroSampaio_TESE.pdf: 4245538 bytes, checksum: 687e089323cb706bdb8dc70fe1aa7593 (MD5) Previous issue date: 2017-04-25 / The high-energy demand involved in the construction industry and the increasing consumption of concrete made this material an ideal option for the recycling of by-products from various industries such as: porcelain polishing residue (PPR); tire rubber residue (TRR) and limestone residue (LSR). These residues often lack a treatment that contributes to the degradation of the environment. In this sense, the use of by-products that increases the volume of the concrete without damaging significantly its properties, can be a viable option in the production of low-cost and sustainable low-weight concrete (LWC). The main objective of this work was to analyze the mechanical and thermal behavior of structural lightweight concrete (SLWC) with low cement consumption, produced with expanded clay (EC) in replacement of the aggregate and with the addition of PPR, TRR and LSR to replace the small aggregate. For this purpose, a 2? factorial design was used for the choice of SLWC with the best performance in terms of consistency, mechanical properties and density. Subsequently, reductions of 10, 20 and 30% of cement were performed on SLWC that presented better combination of properties and waste consumption and were characterized by mechanical tests. The best SLWC mix resulting from the combination of mechanical properties and cement consumption was characterized by permeability, flexural strength, TG/DTA, XRF, SEM, thermal capacity, thermal conductivity and thermal diffusivity. The results showed that residues contents around 21% presented better combination of properties. By maintaining the amount of residue at optimum levels it was possible to produce a SLWC with good rheological, mechanical and thermal properties with minimum cement consumption. / A alta demanda energ?tica envolvida na ind?stria da constru??o civil e o crescente consumo do concreto, fez com que o concreto se tornasse a op??o ideal para a reciclagem de subprodutos de v?rias industrias tais como: res?duo de polimento de porcelanato PPR; res?duo de borracha de pneu (TRR) e res?duo de pedra calc?ria (LSR). Esses res?duos frequentemente carecem de um tratamento adequando o que acaba contribuindo para a degrada??o do meio ambiente. Nesse sentido, o uso de subprodutos que ir?o aumentar o volume do concreto sem prejudicar muito as propriedades, pode ser uma op??o bastante vi?vel na produ??o de Concretos leves (CL) de baixo custo e sustent?veis. O objetivo geral desse trabalho foi analisar o comportamento mec?nico e t?rmico de concretos leves estruturais (CLE) de baixo teor de cimento produzidos com argila expandida (AE) em substitui??o ao agregado gra?do e com adi??o de PPR, TRR e LSR em substitui??o a parte do agregado mi?do. Para tal foi usado inicialmente um planejamento fatorial 2? para a escolha dos CLE com melhor desempenho em termos de consist?ncia, propriedades mec?nicas e massa espec?fica real. Posteriormente foram realizadas redu??es de 10, 20 e 30% de cimento nos CLE que apresentaram melhores desempenhos e caracterizados atrav?s de ensaios mec?nicos. O melhor tra?o resultante da combina??o de propriedades mec?nicas com o consumo de cimento foi caracterizado mediante ensaios de: permeabilidade; resist?ncia ? flex?o; TG/DTA; FRX; MEV; capacidade t?rmica; condutividade t?rmica e difusividade t?rmica. Por fim. Os resultados mostraram que teores de res?duos em torno de 21% apresentaram melhor combina??o de propriedades. Mantendo os teores de res?duos em n?veis ?timos foi poss?vel produzir um CLE com boas propriedades reol?gicas, mec?nicas e t?rmicas com um consumo m?nimo de cimento.
2

Avalia??o do desempenho de argamassas ? base de cimento Portland para rejuntamento de placas cer?micas tipo II com adi??o de p? de borracha de pneus

Queir?s, Jos? Eurico de 15 December 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-06-23T21:56:21Z No. of bitstreams: 1 JoseEuricoDeQueiros_DISSERT.pdf: 2915990 bytes, checksum: 8ca47eabc8fbaa8d3e172df92fb3c088 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-06-28T22:07:28Z (GMT) No. of bitstreams: 1 JoseEuricoDeQueiros_DISSERT.pdf: 2915990 bytes, checksum: 8ca47eabc8fbaa8d3e172df92fb3c088 (MD5) / Made available in DSpace on 2016-06-28T22:07:28Z (GMT). No. of bitstreams: 1 JoseEuricoDeQueiros_DISSERT.pdf: 2915990 bytes, checksum: 8ca47eabc8fbaa8d3e172df92fb3c088 (MD5) Previous issue date: 2015-12-15 / Neste trabalho, avalia-se o desempenho de argamassas ? base de cimento Portland para rejuntamento de placas cer?micas tipo II com adi??o de p? de borracha de pneus inserv?veis. Apresenta-se uma revis?o bibliogr?fica sobre o tema (SEGRE, 1999; MENEGUINI, 2003; FERREIRA, 2009; GUIMAR?ES, 1997; FIORITO, 1994), em que se faz a ancoragem te?rico-metodol?gica de todo o processo investigativo. O universo analisado compreende uma amostra de argamassa para rejuntamento de placas cer?micas tipo II convencional (amostra de refer?ncia) e de mais cinco amostras de argamassas para rejuntamento de placas cer?micas tipo II, compostas com adi??o de p? de borracha de pneu inserv?veis, nas respectivas propor??es de 4, 8, 12, 16 e 20 %. Essas amostras de argamassas foram submetidas aos ensaios de determina??o do ?ndice de consist?ncia (NBR 13276:2005), reten??o de ?gua (NBR 14992 Anexo B:2003), permeabilidade aos 240 minutos (NBR 14992 Anexo G:2003), Absor??o de ?gua por imers?o (NBR 9781:2013), resist?ncia ? compress?o (NBR 14992 Anexo D:2003), resist?ncia ? tra??o na flex?o (NBR 13279:2005), resist?ncia de ader?ncia ? tra??o (NBR 14081 Parte 4:2012) e densidade de massa no estado endurecido (NBR 13280:2005). Constatou-se, a partir das an?lises dos resultados obtidos nos ensaios, a seguinte situa??o: a argamassa de refer?ncia utilizada atendeu ?s exig?ncias estabelecidas nas normas de especifica??es correspondentes para apenas seis do total de oito par?metros avaliados na pesquisa; a argamassa com adi??o de 4,0 % de p? de borracha de pneu atendeu ?s exig?ncias estabelecidas nas normas de especifica??es correspondentes para, apenas, a resist?ncia ? compress?o e a resist?ncia de ader?ncia ? tra??o; as demais argamassas com adi??o de 8,0 %, 12,0 %, 16,0 % e 20,0 % de p? de borracha de pneu atenderam ?s exig?ncias das normas de especifica??es correspondentes, apenas quanto ? resist?ncia de ader?ncia ? tra??o. Esse resultado evidencia a conclus?o de que a adi??o de p? de borracha de pneu n?o confere melhoria de desempenho ?s argamassas. / In this work it is assessed the performance of Portland cement-based mortar to the grouting of type II ceramic plates with the addition of unusable tire rubber powder. It is presented a bibliographical review about the subject in which is done the theoretical and methodological foundation of the whole investigative process. The analyzed universe comprises a sample of mortar to the grouting of conventional ceramic plates type II (reference sample) and five more samples to the grouting of ceramic plates type II, which were made up of the addition of unusable tire rubber powder in the respective proportion (in mass) of 4%, 8%, 12%, 16% and 20%. These mortar samples were subject to the trials of determination of the consistency index (Brazilian Standard NBR 13276:2005), water retention ( Brazilian Standard NBR 14992 Attachment B:2003), permeability in 240 minutes (Brazilian Standard NBR 14992 Attachment G:2003), absorption of water by immersion (Brazilian Standard NBR 9781:2013), resistance to compression (Brazilian Standard NBR14992 Attachment D: 2003), resistance to traction in the flexion (Brazilian Standard NBR 13279:2005), resistance of traction adherence (Brazilian Standard NBR 14081 part 4:2012) and hardened mass density (Brazilian Standard NBR 13280: 2005). It has been found out from the analyzes of the results in the trial the following situation: the reference mortar used met the established requirements in the norms of specifications corresponding to only six from the eight parameters assessed in the research; the mortar with addition of 4,0% of tire rubber powder met the established requirements corresponding to only the resistance to compression and the resistance of adherence to traction. Thus, the other kinds of mortar with addition of 8,0 %, 12,0 %, 16,0 % and 20,0 % of tire rubber powder met the requirements of specifications corresponding to only the resistance to compression and the resistance of adherence to traction. This result concludes that the adding of tire rubber powder does not grant improvement to the mortar of type II grouting to the laying of ceramic plates.
3

Estudo de argamassas de revestimento com res?duo de scheelita / Study of coating mortars with residue scheelite

Medeiros, Mauriceia 19 December 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-03-20T23:06:42Z No. of bitstreams: 1 MauriceiaMedeiros_DISSERT.pdf: 1370833 bytes, checksum: 2a4b653b04c33ca8dac562937c6bb131 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-03-24T21:44:40Z (GMT) No. of bitstreams: 1 MauriceiaMedeiros_DISSERT.pdf: 1370833 bytes, checksum: 2a4b653b04c33ca8dac562937c6bb131 (MD5) / Made available in DSpace on 2017-03-24T21:44:40Z (GMT). No. of bitstreams: 1 MauriceiaMedeiros_DISSERT.pdf: 1370833 bytes, checksum: 2a4b653b04c33ca8dac562937c6bb131 (MD5) Previous issue date: 2016-12-19 / O estado do Rio Grande do Norte possui grande concentra??o de scheelita, principal fonte de Tungst?nio, elemento qu?mico importante na produ??o em diversos segmentos industriais. Ao extrair esse material do mineral bruto, toneladas de res?duos s?o geradas e estocadas no meio ambiente. Com isso, este trabalho tem como objetivo analisar o uso do res?duo de scheelita em substitui??o a areia na formula??o de argamassas de revestimento, devido ?s suas caracter?sticas favor?veis. Foram coletadas amostras do res?duo da scheelita na mina Breju?, Munic?pio de Currais Novos/RN, e ap?s sua caracteriza??o inicial, observou-se a aplica??o do res?duo grosso nas argamassas em estudo. Foram preparadas argamassas de tra?os, 1:1:6 e 1:3, ambos em volume, com percentuais de 0%, 25%, 50%, 75% e 100% de substitui??o da areia pelo res?duo grosso de scheelita. Utilizou-se o cimento Portland CP II-Z 32 e a cal hidratada CH-I, com fator ?gua/cimento entre 0,16 e 0,18 para uma consist?ncia de 260 ? 5mm. Posteriormente as argamassas foram analisadas no estado fresco atrav?s dos ensaios de consist?ncia, densidade de massa, reten??o de ?gua e teor de ar incorporado e no estado endurecido atrav?s dos ensaios de resist?ncia ? compress?o e ? tra??o na flex?o, densidade de massa, absor??o de ?gua por imers?o, absor??o de ?gua por capilaridade e m?dulo de elasticidade din?mico. Os resultados encontrados demonstram uma razo?vel melhoria nas propriedades de resist?ncia mec?nica, m?dulo de elasticidade din?mico e reten??o de ?gua das argamassas produzidas com res?duo da scheelita. No entanto, algumas propriedades como a densidade de massa, absor??o de ?gua por imers?o e por capilaridade apresentaram resultados acima do que foi encontrado para as argamassas de refer?ncia, ocasionando argamassas com maior peso, menor trabalhabilidade e maior absor??o de ?gua que as argamassas de refer?ncia. / The state of Rio Grande do Norte has a large concentration of scheelite, the main source of tungsten, an important chemical element for production in various industries. When extracting the raw mineral material, tons of residue are generated and lunges in the environment. This work aims to analyze the use of this residue as a substitute for sand in the formulation of coating mortars. Scheelite residue samples were collected in Breju? mine, Currais Novos/RN, and after its initial characterization, it was observed the application of the thick residue in the mortars in study. Were analyzed mixing mortars by 1:1:6 (cement:lime:sand) and 1:3 (cement:sand), both in volume with percentages of 0%, 25%, 50%, 75% and 100% of the sand replaced by scheelite thick residue. It was used Portland cement CP II-Z 32 and CH-I hydrated lime with ratio water/cement between 0.18 to 0.16 and a consistency of 260 ? 5mm. Subsequently, the mortars were analyzed in the fresh state through the consistency testing, bulk density, water retention and incorporated air content and in the hardened state by the compressive strength test and tensile strength in bending, bulk density, water absorption by immersion, water absorption by capillary and dynamic modulus of elasticity. The experiments of initial characterization of the residue showed that the natural thick residue has a granulometric distribution very close to the natural sand, has a larger amount of fines and a specific mass higher than natural sand, which resulted to an improvement in mechanical resistance and dynamic modulus of elasticity. X-ray fluorescence (XRF) and x-ray diffraction (XRD) analyzes indicated a pozzolanic propensity of the scheelite residue, but the minimum parameters according to NBR 12653 (2014) to be classified as pozzolanic material were not achieved. In the fresh state, the mortars have improved water retention, allowing greater retention of kneading water. The bulk density presented higher results (about 5% higher) and the incorporated air content, smaller (about 2% lower) in relation to the reference mortar, resulting in dense mortars with less workability, compensated because the natural thick residue had a higher content of fines than sand. In the hardened state, the mechanical resistances recorded higher results. The best results for mortars with 100% replacement of the natural aggregate by residue and trace of 1:3. The bulk density in the hardened state kept the bulk density pattern fresh. And the water absorption by both immersion and capillarity were predominantly larger than the reference mortar. In this way, it is possible to affirm that the residue from the extraction of the scheelite is suitable for use in the manufacture of conventional mortars.
4

Contribui??o ao estudo dos concretos compostos com agregados gra?dos de constru??o e demoli??o e cinza volante, em diferentes teores de substitui??o

Silva, S?rgio Roberto da 30 March 2017 (has links)
Submitted by Caroline Xavier (caroline.xavier@pucrs.br) on 2017-06-30T18:08:23Z No. of bitstreams: 1 DIS_SERGIO_ROBERTO_DA_SILVA_COMPLETO.pdf: 2644731 bytes, checksum: 207623c4aecda0de23cefed577f3f2d6 (MD5) / Made available in DSpace on 2017-06-30T18:08:23Z (GMT). No. of bitstreams: 1 DIS_SERGIO_ROBERTO_DA_SILVA_COMPLETO.pdf: 2644731 bytes, checksum: 207623c4aecda0de23cefed577f3f2d6 (MD5) Previous issue date: 2017-03-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Nowadays, searching for alternatives materials for the construction industry has become imperative. Construction and demolition waste (CDW) and by-products from the thermoelectric industries, such as fly ash, are the subject of studies in several segments of the construction industry. Their use can be one of many significant efforts to achieve a more sustainable construction. This paper studies the influence of the interactions and incorporations of CDW and fly ash on the concrete properties. X-ray diffraction (XRD), X-ray Fluorescence Spectrometry (XRF) and particle size distribution analysis were used to characterize the investigated materials. The mechanical properties (compressive strength and splitting strength) and durability (water absorption and carbonation depth) of concrete with different CDW contents (25%, 50%, 75%, and 100%) were investigated as a coarse aggregate (10%, 15%, 25% and 30%) replacing Portland cement in different water/binder ratios (0.40, 0.45, 0.50, 0, 55 and 0.65). Based on the results, it was observed that the addition of fly ash replacing the Portland cement in concretes with CDW causes a reduction in mechanical properties and durability of concretes in the early ages. However, as the fly ash content increases in concretes with CDW there is an increase in the compressive strength ratio (fc91/fc28), and as the time of exposure to CO2 advances the carbonation coefficient tends to decrease. / A busca de novos materiais para o emprego na ind?stria da constru??o civil se faz necess?rio nos dias atuais. O res?duo da constru??o e demoli??o (RCD) e os subprodutos das ind?strias termoel?tricas como a cinza volante s?o objetos de estudos em diversos segmentos da ind?stria da constru??o civil, e a adi??o destes materiais pode ser um dos esfor?os significativos para se alcan?ar uma constru??o mais sustent?vel. Neste trabalho foram estudadas a influ?ncia das intera??es e incorpora??es de RCD e cinza volante nas propriedades dos concretos. Para a caracteriza??o dos materiais investigados foram utilizadas as t?cnicas de Difra??o de raios X (DRX), an?lise qu?mica por Espectrometria de Fluoresc?ncia de raios X (FRX) e an?lise de distribui??o granulom?trica ? laser. Foram investigadas as propriedades mec?nicas (compress?o axial e tra??o por compress?o diametral) e de durabilidade (absor??o d??gua e resist?ncia ? carbonata??o) dos concretos com diferentes teores de RCD (25%, 50%, 75% e 100%) como agregado gra?do reciclado em substitui??o ao gra?do natural e adi??o de cinza volante (10%, 15%, 25% e 30%) em substitui??o ao cimento Portland em diferentes rela??es ?gua/aglomerante (0,40, 0,45, 0,50, 0,55 e 0,65). Com base nos resultados observou-se que a adi??o de cinza volante em substitui??o ao cimento Portland em concretos com RCD causa uma redu??o nas propriedades mec?nicas e de durabilidade nos concretos nas primeiras idades. Entretanto, ? medida que o teor de cinza volante aumenta nos concretos com RCD h? um aumento na taxa de resist?ncia ? compress?o axial (fc91/fc28), e ? medida que o tempo de exposi??o ao CO2 vai se avan?ando o coeficiente de carbonata??o tende a diminuir.
5

Avalia??o da utiliza??o de res?duo de serragem de Pedra de Cariri (RSPC) na produ??o de argamassa

Rios, Safira Ferreira De Melo 21 August 2017 (has links)
Submitted by Jadson Francisco de Jesus SILVA (jadson@uefs.br) on 2018-01-29T23:45:49Z No. of bitstreams: 1 Disserta??o Safira Ferreira de Melo Rios.pdf: 4123737 bytes, checksum: ac40710a6a79f6c8561eb46f6072996b (MD5) / Made available in DSpace on 2018-01-29T23:45:49Z (GMT). No. of bitstreams: 1 Disserta??o Safira Ferreira de Melo Rios.pdf: 4123737 bytes, checksum: ac40710a6a79f6c8561eb46f6072996b (MD5) Previous issue date: 2017-08-21 / The process of extraction and processing of limestone rocks from the Cariri region of Cear? generates an estimated loss of 70% of the total extracted. The volume of waste generated is significant. To mitigate the environmental impacts generated by the inadequate disposition of the sawdust waste from the Cariri stone (RSPC), the aim of this current study is verify the influence of the use of this waste as a partial replacement of the aggregate in the production of mortars. For this, the natural aggregate was replaced by the RSPC at a rate of 10, 20 and 30%. The cement/sand ratio used was 1: 5 by mass, and the consistency index was fixed in 260 ? 5 mm. Were evaluated the properties of the mortars in the fresh state (water retention, incorporated air content, mass density and rheology through squeeze-flow) and in the hardened state (flexural tensile strength, compressive strength, adhesive strength ,drying shrinkage, absorption byimmersion and void index, and absorption by capillary). The replacement of the natural sand by the RSPC provided an improvement both in the properties of the mortar in the fresh state and in the hardened state. With the exception of the shrinkage, which was higher for the mortars with RSPC, and the adhesive strength, which was equivalent to the reference mortar. In this way, it concludes is possible use of the RSPC as a partial replacement of the natural aggregate. / O processo de extra??o e de beneficiamento da rocha calc?ria da regi?o do Cariri cearense (Pedra Cariri), gera uma perda estimada em 70% do total extra?do. Acarretando um significativo volume de res?duos gerados. Com o intuito de mitigar os impactos ambientais gerados pela disposi??o inadequada do res?duo de serragem da pedra Cariri (RSPC), este trabalho tem como objetivo verificar a influ?ncia da utiliza??o do referido res?duo, como substituto parcial do agregado na produ??o de argamassas. Para tanto, foi realizada a substitui??o, em massa, do agregado natural pelo RSPC nos teores de 10, 20 e 30%. O tra?o utilizado foi 1:5, em massa, e o ?ndice de consist?ncia foi fixado em 260 ? 5 mm. Foram determinadas as propriedades das argamassas no estado fresco (reten??o de ?gua, teor de ar incorporado, densidade de massa e reologia por meio do squeeze-flow) e no estado endurecido (resist?ncia ? tra??o na flex?o, resist?ncia ? compress?o, resist?ncia de ader?ncia ? tra??o, retra??o por secagem, absor??o por imers?o e ?ndice de vazios e absor??o por capilaridade). A substitui??o da areia natural pelo RSPC proporcionou melhoria tanto nas propriedades da argamassa no estado fresco, quanto no estado endurecido. Com exce??o da retra??o, que foi maior para as argamassas com RSPC, e da resist?ncia de ader?ncia ? tra??o, que foi equivalente ? argamassa de refer?ncia. Desta forma, conclui-se que ? poss?vel utilizar at? 30% de RSPC em substitui??o ao agregado natural.
6

Atividade acaricida, inibi??o da acetilcolinesterase e an?lise qu?mica de res?duos agroindustriais

Bispo, Jorge Luiz Peixoto 27 April 2018 (has links)
Submitted by Verena Pereira (verenagoncalves@uefs.br) on 2018-07-12T21:46:04Z No. of bitstreams: 1 JORGE LUIZ PEIXOTO BISPO.pdf: 1928389 bytes, checksum: 3d95674032c8b830a0db8b942fc740ae (MD5) / Made available in DSpace on 2018-07-12T21:46:04Z (GMT). No. of bitstreams: 1 JORGE LUIZ PEIXOTO BISPO.pdf: 1928389 bytes, checksum: 3d95674032c8b830a0db8b942fc740ae (MD5) Previous issue date: 2018-04-27 / The aim of this study was to analyze the in vitro efficacy of crude extracts of agroindustrial residues obtained from fruits against engorged females of Rhipicephalus microplus, using the adult immersion test. The first chapter gathers studies about the fruits used in this study and the bovine ectoparasites of economic importance. In the second chapter, the fruit residues of Spondias mombin, Tamarindus indica, Genipa americana and Citrus latifolia were submitted to maceration with ethanol to obtain the extracts. Engorged females were collected for acaricidal evaluation. The treatments consisted of six groups with extracts at 50 mg mL-1 concentration and two control groups (positive: fipronil and negative: 70 % ethanol). The extract of S. mombin fruit peel showed an acaricidal efficiency of 96.37 %. In order to investigate the mechanism of acaricide action, the in vitro effect of the extracts against acetylcholinesterase was evaluated and only the extract of the bagasse of C. latifolia showed a correlation with the acaricide effect. The extracts were monitored by high performance liquid chromatography and identified derivatives of phenolic compounds. In the third chapter, the fruit extract of S. mombin presented an acaricidal efficacy of 98.4 % at a concentration of 12.5 mg mL-1 and larvicidal efficacy of 84.8 % at a concentration of 25 mg mL-1. After fractionation of the S. mombin extract, the fraction with the major inhibition potential of the acetylcholinesterase enzyme was identified. The active fraction was analyzed by gas chromatography and a mixture of unsaturated fatty acids and terpenoids were identified, which act synergistically in the acaricidal action / O presente trabalho teve como objetivo analisar a efic?cia in vitro dos extratos bruto de res?duos agroindustriais contra f?meas ingurgitadas de Rhipicephalus microplus, utilizando o teste de imers?o de adultos. O primeiro cap?tulo re?ne estudos sobre os frutos utilizados neste trabalho e os ectoparasitos bovinos de import?ncia econ?mica. No segundo cap?tulo, os res?duos dos frutos de Spondias mombin, Tamarindus indica, Genipa americana e Citrus latifolia foram submetidos a macera??o com etanol para obten??o dos extratos. F?meas ingurgitadas foram coletadas para avalia??o acaricida. Os tratamentos foram constitu?dos por seis grupos com extratos na concentra??o 50 mg mL-1 e dois grupos controles (positivo: fipronil; e negativo: etanol 70 %). O extrato da casca do fruto de S. mombin apresentou efic?cia de 96,37 %. Com o intuito de investigar o mecanismo de a??o acaricida, foi avaliado o efeito in vitro dos extratos frente a acetilcolinesterase e apenas o extrato do baga?o de C. latifolia apresentou correla??o com o efeito acaricida. Os extratos foram monitorados por cromatografia l?quida de alta efici?ncia e identificado derivados de compostos fen?licos. No terceiro cap?tulo o extrato da casca do fruto de S. mombin apresentou uma efic?cia acaricida de 98,4 % a uma concentra??o de 12,5 mg mL-1 e efic?cia larvicida de 84,8 % a uma concentra??o 25 mg mL-1. Ap?s o fracionamento do extrato de S. mombin, foi identificada a fra??o com maior potencial de inibi??o da enzima acetilcolinesterase. A fra??o ativa foi analisada por cromatografia gasosa e identificou-se mistura de ?cidos graxos insaturados e terpen?ides, que agem sinergicamente na a??o acaricida
7

Destoxifica??o do farelo de mamona (Ricinus Communis L.) por extrus?o termopl?stica / Detoxification of castor oil (Ricinus communis L.) Thermoplastic Extrusion

Silva, B?rbara Amorim 25 February 2011 (has links)
Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2016-10-04T16:19:04Z No. of bitstreams: 1 2011 - B?rbara Amorim Silva.pdf: 5390134 bytes, checksum: 32ec2143250d4b2b5d5a8de98ea88d9d (MD5) / Made available in DSpace on 2016-10-04T16:19:04Z (GMT). No. of bitstreams: 1 2011 - B?rbara Amorim Silva.pdf: 5390134 bytes, checksum: 32ec2143250d4b2b5d5a8de98ea88d9d (MD5) Previous issue date: 2011-02-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / The castor bean (Ricinus communis L) is a plant family Euphorbiaceae. Considered an oil of high economic value because this has a clearly defined market for the oil extracted from its seeds. The cake, which is a residue of this extraction, stands out for its high protein content. Among the proteins found in the cake stands ricin, a cytotoxin, which not allows its use as an alternative protein source for animal feed. In this study was used the extrusion-cooking technology, combined application of calcium hydroxide Ca(OH)2 in order to inactivate the protein fraction containing ricin. The extrusion process of cake castor oil was carried out using a Brabender DS20 cannon short. Was used the response surface methodology to investigate the effect of the interaction of parameters in the study. Was used a central composite design in order to evaluate the moisture effects (14%, 16%, 18%, 20%, and 21%), temperature (116?C, 130?C, 150?C, 170?C and 180?C) and concentration of Ca(OH)2.. As a comparative sample was used castor beans which were crushed to extract oil and cake which used as a sample without heat treatment, as standard. For the evaluation of physical-chemical, it was utilized methods of AOAC. The quantification of proteins was realized using the method of Bradford and the protein profile was electrophoresis-SDS-PAGE. Was used to mark the Biorad electrophoresis the methodology observed using the of preparation of the gels described by LaemmLi (1970). The results indicated that most of the different treatments performed totally changed the structure of ricin. Indizatily the possibility of total hydr?lise of this macromolecule. The application of extracts of castor oil in the gel electrophoresis allowed the observation of a clear chain A (RTA) and 38 kDa molecular weight B (RTB) molecular weight 36kDa. For the crude protein extract of bran molar mass chains A and B were approximately 37 kDa and 35 kDa respectively. The levels of protein extracted from the bran decreased 89% after extrusion. The results indicated that all treatments changed entirely the structure of ricin with the possibility of their having been a total hydrolysis of the polymer. According to tests performed and observed results, we conclude that the thermoplastic extrusion process is a suitable technology to decrease the activity of ricin / A mamoneira (Ricinus communis L.) ? uma planta da fam?lia Euforbi?cea que vem sendo muito estudada como fonte alternativa na produ??o de biodisel. O farelo, res?duo gerado ap?s a extra??o do ?leo da semente utilizando solvente, apresenta alto teor de prote?nas. Dentre as prote?nas encontradas na torta destaca-se a ricina, uma citotoxina, que inviabiliza sua utiliza??o como fonte prot?ica alternativa para alimenta??o animal. No presente estudo empregamos a extrus?o termopl?stica, associada ? aplica??o de hidr?xido de c?lcio Ca (OH)2 com o objetivo de inativar a fra??o prot?ica que contem a ricina. O processo de extrus?o do farelo de mamona foi realizado utilizando uma extrusora BRABENDER DS20 de canh?o curto. Utilizou-se a metodologia de superf?cie de resposta para verificar o efeito da intera??o dos par?metros estabelecidos no estudo. Foi utilizado um delineamento composto central rotacional a fim de avaliar os efeitos dos n?veis de umidade (14%, 16%, 20% e 21%), temperatura (116?C, 130?C, 150?C, 170?C e 180?C) e concentra??o Ca(OH)2.. Como amostra comparativa foi utilizada sementes de mamona da cultivar Paragua?? as quais foram esmagadas em prensa expeller at? extrair o ?leo e cuja torta foi utilizada como padr?o por apresentar maior integridade das cadeias polipept?dicas. Para a avalia??o das caracter?sticas f?sico-qu?micas, foram utilizados m?todos da AOAC, para quantifica??o de prote?nas foi utilizado o m?todo de Bradford e para avalia??o do perfil prot?ico foi utilizada a eletroforese- SDS-PAGE, atrav?s do sistema de eletroforese da marca Biorad com a metodologia de prepara??o dos g?is descrita por Laemmli (1970). Os m?todos de purifica??o usando a di?lise e precipita??o com sulfato de am?nio favoreceu para um bom rendimento quanto ao teor de prote?na, principalmente a ricina. A aplica??o dos extratos da torta de mamona no gel de eletroforese permitiu a observa??o n?tida das cadeias A (RTA) massa molar 38 kDa e B (RTB) massa molar 36kDa. Para o extrato prot?ico do farelo bruto a massa molar das cadeias A e B ficaram em torno 37 kDa e 35 kDa respectivamente. Os n?veis de prote?na extra?da do farelo diminu?ram 89% ap?s a extrus?o. Os resultados indicaram que todos os tratamentos realizados modificaram totalmente a estrutura da ricina, com possibilidade de ter havido hidr?lise total desta macromol?cula. De acordo com os ensaios realizados e resultados observados, conclui-se que o processo de extrus?o termopl?stica ? uma tecnologia adequada para diminuir a atividade da ricina. Palavras-chave: Citotoxina, Eletroforese
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Efeito da aplica??o de res?duo de perfura??o de po?o de petr?leo no desenvolvimento de cevada (Hordeum vulgare L.) / Effect of application of drill cuttings from oil well in the development of barley (Hordeum vulgare L.)

CARVALHO, Michel Miranda de 26 April 2013 (has links)
CNPq / Faced with the need to implement a sustainable development, and seeking solutions for protecting the environment, the management of residues has undergone marked changes. Companies are increasingly involved in the optimization of residues produced in their production processes. The oil industry participates in this search by funding research and development of environmentally sound technologies. This study aimed to evaluate the development of barley plants (Hordeum vulgare L.) in soils incubated with drill waste from oil well treated by washing to eliminate the influence of sodium. Two residues generated during drilling of the well 7-SMC-50D-AL were selected to be used in two assays: one in pots planted with barley, and one with leaching columns. For the pots testing the residues were washed with water, using a ratio of 1:5, aiming to reduce the effects of the sodium. Thus, the washing treatment defined two other conditions: residue washed and unwashed. The quantity of residue added to the soil was defined in order to obtain the barium concentrations of 300 mg kg-1, 600 mg kg-1 and 1200 mg kg-1. The soil moisture was maintained at 70% of field capacity. The experimental units were kept incubated for 30 days, and covered with plastic bags to prevent water loss by evaporation. The plants sowing was made using 10 seeds in each pot, and after the thinning with 30 days there was left 4 plants per pot. After the harvesting, the plants were separated into root, shoot and grain; and it was evaluated the absorption of the elements barium, iron, manganese, calcium, sodium, zinc and potassium. The results showed that the residues of the centrifugal and the dryer promoted an increased production of plant dry matter, especially in the treatment with the residue washing. For the test columns, there was no washing of the residues. The same doses were tested with two conditions of humidity (70% of field capacity and reduced condition, simulating the presence of a ground water table). During the incubation the pH and the redox potential (Eh) were monitored until, in the reduction condition, values close to ? 200 mV were obtained, and then, waiting for 30 days to ensure the occurrence of the reduction reactions. After that, the leaching test proceeded, simulating rainfall and collecting the extract leachate to evaluate the barium content. The geochemical fractionation of barium was done using a modification of the BCR method. The fractionation results showed that the reduction condition provided greater availability of barium, increasing the bioavailable fraction for both cuttings. In the leaching test, there was an increase in barium level in the reduction condition, due to the reduction of sulfate to sulfide. / Diante da necessidade de implementar o desenvolvimento sustent?vel, buscando solu??es para a prote??o do meio ambiente, a gest?o de res?duos tem passado por mudan?as marcantes. As empresas est?o cada vez mais envolvidas na otimiza??o de res?duos produzidos em seus processos produtivos. A ind?stria petrol?fera participa dessa busca por solu??es atrav?s do financiamento de pesquisas e do desenvolvimento de tecnologias ambientalmente seguras. Este trabalho teve como objetivo avaliar o desenvolvimento de plantas de cevada (Hordeum vulgare L.) em solos incubados com res?duos de perfura??o de po?o de petr?leo tratados com lavagem para eliminar a influ?ncia do s?dio. Foram selecionados dois res?duos gerados durante a perfura??o do Po?o7-SMC-50D-AL para serem utilizados em dois ensaios: um com vasos cultivados com cevada e outro com colunas de lixivia??o. Para o ensaio com vasos foi feita a lavagem dos res?duos em ?gua, na propor??o 1:5, visando diminuir os efeitos do s?dio. Dessa forma, o tratamento de lavagem definiu duas condi??es: res?duo lavado e res?duo n?o lavado. A quantidade de res?duo adicionada ao solo foi definida de modo a atingir as concentra??es de b?rio de 300 mg kg-1, 600 mg kg-1 e 1200 mg kg-1. A umidade do solo foi mantida a 70% da capacidade de campo. As unidades experimentais permaneceram incubadas por 30 dias, cobertas com sacos pl?sticos para evitar a perda de ?gua por evapora??o. Em seguida foi feita a semeadura, utilizando 10 sementes em cada vaso, e com o desbaste ap?s 30 dias restaram apenas 4 plantas por vaso. Ap?s a coleta as plantas foram separadas em raiz, parte a?rea e gr?os e foi avaliada a absor??o dos elementos b?rio, ferro, mangan?s, c?lcio, s?dio, zinco e pot?ssio. Os resultados obtidos demonstraram que os res?duos do secador e da centr?fuga promoveram aumento da produ??o de mat?ria seca pelas plantas, principalmente no tratamento lavado. Para o ensaio com colunas n?o houve lavagem dos res?duos. Foram testadas as mesmas doses em duas condi??es de umidade (70% da capacidade de campo e ambiente reduzido com presen?a de l?mina de ?gua). Durante a incuba??o foi feito o monitoramento de pH e potencial redox (Eh) at? que, na condi??o de redu??o, fossem atingidos valores pr?ximos de -200 mV, aguardando por 30 dias para assegurar a ocorr?ncia das rea??es de redu??o. Em seguida foi feito o ensaio de lixivia??o, simulando uma precipita??o e coletando o extrato lixiviado para avalia??o quanto ao teor de b?rio. Foi feito o fracionamento geoqu?mico do elemento b?rio utilizando-se o m?todo BCR com algumas modifica??es. Os resultados mostraram que no fracionamento as fra??es biodispon?vel para ambos os res?duos na condi??o de redu??o proporcionou uma maior disponibilidade do b?rio. Na lixivia??o houve um aumento dos teores de b?rio na condi??o de redu??o proporcionado pela redu??o de sulfato a sulfeto.
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Influ?ncia do tratamento de lavagem de res?duos de perfura??o de po?os de petr?leo no desenvolvimento de plantas de arroz (Oryza sativa) / Influence of the treatment of dry waste from drilling of oil wells in the development of rice plants (Oryza sativa)

LIMA, Leilane da Silva 04 March 2013 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-10-04T17:50:04Z No. of bitstreams: 1 2013 - Leilane da SIlva Lima.pdf: 2571314 bytes, checksum: 6a887a80293fe4214d8df0859a55db54 (MD5) / Made available in DSpace on 2017-10-04T17:50:04Z (GMT). No. of bitstreams: 1 2013 - Leilane da SIlva Lima.pdf: 2571314 bytes, checksum: 6a887a80293fe4214d8df0859a55db54 (MD5) Previous issue date: 2013-03-04 / CNPq / A major environmental issue is the impact caused by the extraction of primary materials and the waste disposal. The industry tries to change that with adjustments in the production chain to reduce impacts to the environment. However, this is a subject that has few studies. This study aimed to evaluate the development of rice plants (Oryza sativa) in soils incubated with waste from drilling oil wells, treated by washing to eliminate the influence of sodium and under two moisture conditions. Two residues generated during the drilling of the well 7-SMC- 50D AL were selected. Subsequently, the residue washing was done in water with the 1:5 proportions, to reduce the effects of sodium. Thus, the washing treatment defined two conditions: washed and unwashed residues. The amount of residue added to the soil was set to achieve concentrations of barium of 300 mg kg-1, 600 mg kg -1 and 900 mg kg-1. The soils were kept in two moisture conditions (70% of field capacity and waterlogged to get a reduced condition). During the incubation of vessels the redox potential (Eh) was monitored until values close to -200 mV was reached, in the reduction condition. After reaching these values, we waited up to 30 days before transplanting the rice seedlings and the test starting. Samples were collected from each experimental unit, and the elements barium, iron, manganese, calcium, sodium and potassium were analyzed. The rice was planted, and went throughout the vegetative cycle (approximately 3 months) until the plants were harvested for analysis. The results showed that the residues from the dryer and the centrifuge, with and without washing, in the oxidized condition, did not affect the dry matter yield of the rice plants. However, the soil reduction condition promoted increasing concentrations of barium absorbed by plants, and reduced the iron level. In the treatments with the residue and reduction condition, the solubilization of barium combined with a moderate iron deficiency possible interfered on dry matter production. / Uma grande quest?o ambiental ? o impacto causado pela extra??o de materiais prim?rios e pela deposi??o de res?duos. A ind?stria tenta mudar esse cen?rio com adequa??es ao longo da cadeia produtiva para diminuir os impactos ao meio ambiente. Entretanto, essa ? uma ?rea ainda pouco estudada.Este trabalho teve como objetivo avaliar o desenvolvimento de plantas de arroz (Oryza sativa) em solos incubados comres?duos de perfura??o de po?o de petr?leo tratados com lavagem para eliminar a influ?ncia do s?dio e sob duas condi??es de umidade. Foram selecionados dois res?duos gerados durante a perfura??o do Po?o7-SMC-50D-AL. Posteriormente, foi feita a sua lavagem em ?gua, na propor??o 1:5, visando diminuir os efeitos do s?dio. Dessa forma, o tratamento de lavagem definiu duas condi??es: res?duo lavado e res?duo n?o lavado. A quantidade de res?duo adicionada ao solo foi definida de modo a atingir as concentra??es de b?rio de 300 mg kg-1, 600 mg kg-1 e 900 mg kg-1. Os solos foram mantidos em duas condi??es de umidade (70% da capacidade de campo e reduzido com presen?a de l?mina de ?gua). Durante a incuba??o dos vasos foi monitorado o potencial redox (Eh) at? que, na condi??o de redu??o, fossem atingidos valores pr?ximos de -200mV. Ap?s atingir esses valores, aguardou-se 30 dias para o transplantio das mudas de arroz e in?cio da realiza??o do ensaio. Foram coletadas amostras de cada unidade experimental, onde foram feitas an?lises dos elementos b?rio, ferro, mangan?s, c?lcio, s?dio e pot?ssio. Foi realizado o plantio do arroz, permanecendo durante todo ciclo vegetativo (aproximadamente 3 meses) at? serem colhidas as plantaspara an?lise. Os resultados obtidos demonstraram que os res?duos do secador e da centr?fuga, com e sem lavagem, na condi??o de oxida??o, n?o interferiram na produ??o de mat?ria seca das plantas de arroz. Entretanto, a condi??o de redu??o do solo promoveu o aumento dos teores de b?rio absorvidos pelas plantas e redu??o nos de ferro. Nos tratamentos com res?duo e na condi??o de redu??o, a solubiliza??o de b?rio combinada a uma defici?ncia moderada para ferro levou a uma poss?vel interfer?ncia na produ??o de mat?ria seca.
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Estudo do comportamento no estado fresco e endurecido do concreto com incorpora??o de res?duo de corte de bot?o

Avelino, Veruska Kelly Gomes Rocha 21 June 2011 (has links)
Made available in DSpace on 2014-12-17T14:48:10Z (GMT). No. of bitstreams: 1 VeruscaKGR_DISSERT.pdf: 1561104 bytes, checksum: 8cf444f0891dd9cd7517204b9dd26c41 (MD5) Previous issue date: 2011-06-21 / This works aims at investigating the effects of adding waste from RCBP-polyester button manufacturing to Portland cement concrete, particularly regarding its consistency and mechanic strength. The RCBP used came from a button factory located in Parnamirim, RN, Brazil. The waste was added to the concrete on different ratios: 5 %, 10 %, 15 % and 20 % of the total cement mass. A sample of concrete without the RCBP was used as reference, 1:1,33:2,45:0,50. For the mechanic strength test four samples were tested with different ages (3, 7 and 28 days old) and mixtures. Furthermore, a Slump Test was also conducted in order to verify the concrete s consistency. A tendency to a reduction in the compression resistance was noticed for all samples. For the samples with 5 % and 10 %, there was also an increase in the traction resistance during inflexion, regarding the reference concrete. In the microstructural analysis, the RBCP was observed to show an irregular and porous surface, thus explaining the consistency decrease / O presente trabalho objetivou avaliar a influ?ncia da incorpora??o do res?duo de corte de bot?o em poli?ster-RCBP sobre a plasticidade e a resist?ncia mec?nica em concreto de cimento Portland. O RCBP utilizado na pesquisa originou-se do material descartado por uma empresa fabricante de bot?o localizada no munic?pio de Parnamirim/RN. Utilizou-se o res?duo, como carga no concreto, nas concentra??es de 0 %, 5 %, 10 %, 15 % e 20 %, em rela??o ? massa do cimento. O tra?o de refer?ncia do concreto utilizado na pesquisa apresenta a propor??o, em massa, de 1:1,33:2,45:0,50 (cimento:areia:brita:?gua/cimento). Nos ensaios de resist?ncia ? compress?o foram testados quatro corpos-de-prova para cada idade (3, 7 e 28 dias) e tra?o, enquanto que para os ensaios de resist?ncia ? tra??o na flex?o foram testados dois corpos-de-prova para cada tra?o. Al?m disso, fez-se o Slump Test, com vistas a verificar a consist?ncia do concreto. Observou-se uma tend?ncia de redu??o da resist?ncia ? compress?o e abatimento para todos os tra?os com incorpora??o do RCBP. Houve um aumento de resist?ncia ? tra??o na flex?o para os tra?os de 5 % e 10 %, em rela??o ao concreto sem incorpora??o do res?duo, superando o sugerido pela NBR 6118/2003 que apresenta uma correla??o entre resist?ncia ? tra??o e ? compress?o. Na an?lise microestrutural, observou-se que o RCBP apresentou uma superf?cie irregular e porosa, podendo ser o motivo do decr?scimo do abatimento

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