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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

Bebida l?ctea fermentada elaborada com Camellia sinensis / Fermented milk elaborated with Camellia sinensis

Ribeiro, Ot?vio Augusto Silva 27 March 2013 (has links)
Submitted by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-13T12:14:07Z No. of bitstreams: 2 otavio_augusto_silva_ribeiro.pdf: 545164 bytes, checksum: d56f5a2896e7b9e509a0cb0f76970414 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-13T12:14:47Z (GMT) No. of bitstreams: 2 otavio_augusto_silva_ribeiro.pdf: 545164 bytes, checksum: d56f5a2896e7b9e509a0cb0f76970414 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-13T12:14:45Z (GMT) No. of bitstreams: 2 otavio_augusto_silva_ribeiro.pdf: 545164 bytes, checksum: d56f5a2896e7b9e509a0cb0f76970414 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2015-01-13T12:15:28Z (GMT) No. of bitstreams: 2 otavio_augusto_silva_ribeiro.pdf: 545164 bytes, checksum: d56f5a2896e7b9e509a0cb0f76970414 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) / Made available in DSpace on 2015-01-13T12:15:28Z (GMT). No. of bitstreams: 2 otavio_augusto_silva_ribeiro.pdf: 545164 bytes, checksum: d56f5a2896e7b9e509a0cb0f76970414 (MD5) license_rdf: 22974 bytes, checksum: 99c771d9f0b9c46790009b9874d49253 (MD5) Previous issue date: 2013 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A presente pesquisa foi conduzida com o objetivo de se desenvolver e caracterizar bebida l?ctea fermentada formulada com Camellia sinensis. Procedeu-se a elabora??o da infus?o de folhas desidratadas e picadas de C. sinensis em soro l?cteo (1g.100g-1) a qual foi adicionada em leite ado?ado (sacarose 10% p/p), coagulado por Streptococcus salivarius subsp. thermophilus e Lactobacillus delbrueckii subsp. bulgaricus nas propor??es de 10, 20, 30 e 40% (v/p). O controle consistiu em iogurte adicionado com sacarose (10% p/p). Procedeu-se ?s determina??es de massa seca, umidade, res?duo mineral fixo, prote?na, gordura, s?dio, acidez, quantifica??o de bact?rias l?ticas totais, atividade antioxidante total e viscosidade no tempo inicial de fabrica??o e em 15 e 30 dias de armazenamento. No produto, em seu tempo inicial de fabrica??o, procedeu-se a determina??o cromatogr?fica de compostos vol?teis e ? condu??o dos testes sensoriais de aceita??o e inten??o de consumo. O teor de massa seca, a umidade, res?duo mineral fixo e contagem total de bact?rias l?ticas de formula??es de bebida l?ctea fermentada n?o foram significativamente afetados pela quantidade de infus?o de C. sinensis adicionada. Entretanto, o conte?do de prote?na, gordura e s?dio foram significativamente menores, quanto maior a percentagem de infus?o incorporada ao produto. Houve redu??o significativa na viscosidade aparente do produto mediante o aumento da quantidade de infus?o adicionada. A atividade antioxidante total das formula??es foi significativamente maior quanto maior a quantidade de infus?o adicionada. A adi??o de infus?o contribuiu para a diversifica??o de compostos vol?teis formadores de aroma e sabor no produto. A formula??o de bebida l?ctea fermentada, com adi??o de 30% de infus?o de C. sinensis em soro l?cteo, foi a preferida em testes sensoriais, com maior aceita??o e maior inten??o de consumo. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Zootecnia, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2013. / ABSTRACT The aim of this research was to develop and to characterize fermented dairy beverage formulated with Camellia sinensis. Infusion was elaborated with the addiction of dehydrated leaves of C. sinensis in whey (1g.100g-1) which added in sweetened milk (10% sucrose w/w) coagulated by Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus in proportions of 10, 20, 30 and 40% (v/ w). The control treatment consisted of yogurt added with sucrose (10% w / w). Analysis were performed to quantify dry mass, moisture, ash, protein, fat, sodium, acidity, total quantification of lactic acid bacteria, total antioxidant activity and viscosity at the initial time of production and at 15 and 30 days of storage. Chromatographic determination of volatile compounds and sensory tests of acceptance and consumption intention were conducted at the initial time of production. Dry matter content, moisture, ash and total count of lactic acid bacteria from fermented milk drink formulations were not significantly affected by the amount of infusion of C. sinensis. However, the content of protein, fat and sodium were significantly lower with the increase of the proportion of infusion incorporated into the product. Significant reduction in apparent viscosity occurs with the increase in the amount of infusion added. The total antioxidant activity of the formulations was significantly higher as higher were the amount of added infusion. The addition of infusion contributed to the diversification of volatile aroma and taste makers in the product. The formulation of fermented dairy drink with addition of 30% Infusion C. sinensis was better evaluated in sensory tests, with greater acceptance and greater consumer intent of consumption.
2

Avalia??o da atividade biol?gica de ?leos essenciais sobre candida n?o albicans de origem cl?nica

Abrantes, Maiza Rocha de 06 December 2013 (has links)
Made available in DSpace on 2014-12-17T14:13:50Z (GMT). No. of bitstreams: 1 MaizaRA_TESE.pdf: 1687383 bytes, checksum: 6a89b25caa7db5fc536b4051629db0e3 (MD5) Previous issue date: 2013-12-06 / Candid?ase ? um problema de import?ncia crescente, devido o aumento do n?mero de indiv?duos imunocomprometidos e o surgimento de cepas resistentes aos antif?ngicos convencionais. ? de fundamental import?ncia a busca por novos agentes antif?ngicos mais eficazes, menos t?xicos, sendo os ?leos essenciais (OEs) excelentes alternativas para esse prop?sito. Esse estudo investigou a atividade biol?gica do OE de Mentha spicata L. sobre Candida guilliermondii de origem anal e vaginal. Para tanto foram determinadas a Concentra??o Inibit?ria M?nima (CIM), Concentra??o Fungicida M?nima (CFM), cin?tica do crescimento das leveduras (Time-Kill), altera??es micromorfol?gicas (t?cnica do microcultivo em c?mara ?mida) e investiga??o do mecanismo de a??o antif?ngico, utilizando o bioensaio do sorbitol. O OE de M. spicata foi obtido pelo processo de extra??o por destila??o a vapor. Na an?lise fitoqu?mica desse ?leo foi observada a presen?a de carvona com 84,32%, seguida pelo limoneno (13,70%) e tra?os de iso-dihidrocarvona (0,82%). Os resultados da an?lise da CIM variou entre 32 e 128 μg/mL. A CFM variou entre 64 e 1024 μg/mL. Na avalia??o da a??o de OE e da nistatina 100UI/mL, o antif?ngico padr?o apresentou o efeito fungicida a partir de 4 horas e para OE de M. spicata foi observado efeito fungist?tico na CIM, CIMX2 e CIMX4 frente ?s cepas avaliadas. O OE de M. spicata apresentou forte atividade antif?ngica contra as cepas de C. guilliermondii, promovendo altera??es micromorfol?gicas vis?veis por microscopia ?ptica, nas concentra??es testadas (CIM, CIMx2), resultado semelhante ao que se observou com a nistatina (100UI/mL). Na investiga??o do mecanismo de a??o antif?ngico foi constatado que houve altera??o da CIM na presen?a de sorbitol, com eleva??o dos valores quatro vezes maior que a concentra??o inicial, o que indica que os componentes desse OE apresentam a??o direta sobre a parede celular das leveduras. Conclui-se que o OE de Mentha spicata ? um potencial agente terap?utico no tratamento de candid?ase
3

Atividades biol?gicas e composi??o qu?mica dos ?leos essenciais de Achyrocline satureoides (Lam) DC. e Ageratum conyzoides L. encontradas no semi?rido baiano

Gon?alves, Jacqueline Miranda 28 September 2015 (has links)
Submitted by Ricardo Cedraz Duque Moliterno (ricardo.moliterno@uefs.br) on 2016-01-19T23:08:21Z No. of bitstreams: 1 TESE DOUTORADO VERS?O FINAL.pdf: 3041272 bytes, checksum: e0025693076836f6a3804cc2aaf6a529 (MD5) / Made available in DSpace on 2016-01-19T23:08:21Z (GMT). No. of bitstreams: 1 TESE DOUTORADO VERS?O FINAL.pdf: 3041272 bytes, checksum: e0025693076836f6a3804cc2aaf6a529 (MD5) Previous issue date: 2015-09-28 / Essential oils are complex mixtures of various isolates of plant secondary metabolites. Due to the increased use of these aromatic compounds, research has been developed, and the development of new products. This study analyzed the antimicrobial, cytotoxic and immunomodulatory activities in addition to the phytochemical profile of essential oils Achyrocline satureoides and Ageratum conyzoides. The micro-organisms most sensitive to oils were Staphylococcus aureus CCMB 262 and Candida kruzei CCMB 287. The essential oil of A. conyzoides was considered non-toxic in the tested conditions. In the assessment of the immune response induced by oils, although they were not statistically significant differences between the concentrations tested and control, it was observed that the essential oils inhibited the production of IL-8 and IL-12 cytokines with exception of the species A. satureoides at a concentration of 100 mg / mL. This behavior may suggest the capacity reduction of the inflammatory response. The chromatographic analysis of essential oils of A. satureoides demonstrated a chemical profile consistent with the literature where the major components were ?-Pinene, E-caryophyllene, ?-copaene, ?-humulene, d-cadinene. Since the analysis of oils A. conyzoides showed conflicting results in the literature which suggests a new chemotype, since the presence of precocenos the chemical analysis was not observed. / Os ?leos essenciais s?o misturas complexas de metab?litos secund?rios isolados de diversas plantas. Devido ao aumento do uso destes compostos arom?ticos, pesquisas v?m sendo desenvolvidas, al?m do desenvolvimento de novos produtos. O presente trabalho analisou as atividades antimicrobiana, citot?xica e imunomoduladora, al?m do perfil fitoqu?mico de ?leos essenciais de Achyrocline satureoides e Ageratum conyzoides. Os micro-organismos mais sens?veis aos ?leos foram Staphylococcus aureus CCMB 262 e Candida kruzei CCMB 287. O ?leo essencial de A. conyzoides foi considerado at?xico nas condi??es testadas. Em rela??o ? avalia??o da resposta imune induzida pelos ?leos, apesar de n?o terem sido encontradas diferen?as estatisticamente significantes entre as concentra??es testadas e o controle, p?de-se observar que os ?leos essenciais inibiram a produ??o das citocinas IL-8 e IL-12, com exce??o da esp?cie A. satureoides na concentra??o de 100 ?g/mL. Este comportamento pode sugerir a capacidade de redu??o da resposta inflamat?ria. As an?lises cromatogr?ficas dos ?leos essenciais de A. satureoides demonstrou um perfil qu?mico em concord?ncia com a literatura onde os componentes majorit?rios foram ?-Pineno, E-Cariofileno, ?-Copaeno, ?-Humuleno, d-Cadineno. J? as an?lises dos ?leos de A. conyzoides apresentou resultados divergentes da literatura o que nos sugere um novo quimiotipo, uma vez que n?o foi observada a presen?a de precocenos nas an?lises qu?micas.
4

One-Dimensional Performance Modeling of Centrifugal Flow Vaned Diffusers

Bitter, Jamin J. 02 March 2007 (has links) (PDF)
The Two Element in Series (TEIS) and Two Zone models stand out as powerful tools that enable deeper understanding of compressor stage designs after they have been tested. The insights gained from these investigations have aided in improving new stage designs. Up to now, it has only been possible to use the TEIS and Two Zone models for analysis of test data due to the inability to predict the four required input parameters for untested machines. Empirical models for the TEIS and Two Zone model input parameters, ETAa5, ETAb5, Chi5, and DELTA5p, for two different types of vaned diffusers, channel and cascade, are proposed. These models were developed with frozen impeller modeling. This is the first time that modeling the TEIS and Two Zone input parameters has been attempted for vaned diffusers and impeller-diffuser coupling was not considered in this initial investigation. The centrifugal compressor experimental data used in the model building was obtained from Concepts NREC, an industry sponsor. Each dataset provided was evaluated for quality and reliability and only the data deemed reliable were used in the model building databases. The empirical models presented are built solely on this higher quality data. Seven models are proposed for use in predicting the TEIS and Two Zone model input parameters ETAa5, ETAb5, Chi5, and DELTA5p. Models for ETAa5, ETAb5, and DELTA5p are specific to the type of vane present in the diffuser, while the model for Chi5 is common to both diffuser types. These are the first models ever built for the TEIS and Two Zone model inputs applied to channel and cascade diffusers and become a benchmark for future studies. The work with these models is not complete, however. The databases are not of a size that data could be withheld from empirical model building for the express purpose of validation. Instead the model performance is evaluated by applying all of the models, simultaneously, to the database from which they were built. The determination of the effectiveness of the combined modeling is based on the average error across the entire speedline. The models proved to be effective and a contributing step to employing such models for use in future compressor design.
5

One-Dimensional Radial Flow Turbomachinery Performance Modeling

Pelton, Robert John 03 December 2007 (has links) (PDF)
The Two-Element In Series (TEIS) and Two-Zone models have been used successfully for over twenty years to model test data for radial flow compressors and pumps. The models can also be used to predict the performance of new machines provided that the model inputs can be accurately specified. Unfortunately, use of the TEIS and Two-Zone models as a predictive tool has been limited because an accurate and broadly applicable method of predicting the modeling parameters, etaA, etaB, chi and d2p does not exist. Empirical models have been developed to predict the TEIS and Two-Zone modeling parameters based on a large database of centrifugal pump and compressor test results. These test data were provided by ConceptsNREC and have been collected over the past 40 years. The database consists of a wide range of machines including some that were designed and tested by ConceptsNREC and others from the open literature. Only cases with a vaneless diffuser or volute have been included in the analysis to avoid any possible impeller-diffuser interactions. From the database, models for all of the TEIS and Two-Zone parameters have been derived using basic regression techniques. Three different models are proposed for each of the two TEIS modeling parameters, etaA and etaB. One model for pumps, another for compressors, and a combined model applicable for all machines is given. For the Two-zone parameters, chi and d2p, a single set of models was developed to represent the design point performance and another showing how chi and d2p vary off-design. The combined models for etaA and EtaB are 30% and 70% more accurate than the current state-of-the-art models, respectively. The new models account for the variance in chi and d2p at off-design flow conditions and further refine the accuracy of the overall prediction by correctly modeling the loss mechanisms in the impeller passage. Validation work has shown that the set of models that predict etaA, etaB, chi and d2p can be solved to consistently produce sensible results and yield a reasonable "blind" prediction of the performance of a wide range of radial compressors and pumps. These models constitute the first broadly applicable method for predicting the required TEIS and Two-Zone variables and are sufficiently accurate to provide initial performance estimates of new impeller designs
6

Degrada??o de compostos org?nicos vol?teis usando o catalisador SBA-15 contendo tit?nio

Alves, Camila Graciele Rolim 02 May 2012 (has links)
Made available in DSpace on 2014-12-17T15:42:01Z (GMT). No. of bitstreams: 1 CamilaGRA_DISSERT.pdf: 2325529 bytes, checksum: 83d27b47b244a6da7127c42df79472b8 (MD5) Previous issue date: 2012-05-02 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The groundwater pollution arising due to fuel leaks gas stations has presented a problem aggravating. Increasingly studies related to environmental problems such accidents and seek to propose some solutions for the treatment of groundwater and soils that are contaminated by gasoline. This study evaluated the use of molecular sieve TiSBA-15 as a catalyst for the reaction of removing of volatile organic compounds, particularly benzene, toluene, ethylbenzene and xylenes, known as BTEX, one of the main pollutants found in groundwater. The catalyst was synthesized by the method post-synthesis techniques and characterized by XSD, TG/DTG, adsorption/desorption of N2, XRF-EDX, for checking the incorporation of titanium and formation of the structure of the catalyst. The reaction occurred with the presence of hydrogen peroxide, H2O2, in aqueous medium to form hydroxyl radicals, which are needed in the process of removal of BTEX compounds. The catalytic reaction was carried out for 5 hours at 60 ?C, pH to 3.0, and analyzes of the compounds were made in a gas chromatograph with a flame detection means photoionization static headspace (HS-GC-PID). The catalytic tests have shown the efficacy of using this type of catalyst for the removal of these volatile organic compounds, having a removal rate of 90.60% in the range where the catalyst was studied TiSBA-15(5,0) / A polui??o das ?guas subterr?neas devido a decorrentes vazamentos de combust?vel por postos de gasolina tem se apresentado um problema agravante. Cada vez mais estudos relacionam problemas ambientais com tais acidentes e procuram propor algumas solu??es para o tratamento das ?guas subterr?neas e solos que s?o contaminados pela gasolina. Este trabalho avalia o uso da peneira molecular TiSBA-15 como catalisador da rea??o de remo??o de compostos org?nicos vol?teis, especificamente benzeno, tolueno, etilbenzeno e xilenos, conhecidos como BTEX, um dos principais poluentes encontrados em ?guas subterr?neas. O catalisador foi sintetizado pelo m?todo p?s-s?ntese e caracterizado pelas t?cnicas de DRX, TG/DTG, adsor??o/dessor??o de N2, e FRX-EDX. O estudo da atividade catal?tica da TiSBA- 15 ocorreu com a presen?a de per?xido de hidrog?nio, H2O2, em meio aquoso, para a forma??o de radicais hidroxilas, os quais ser?o necess?rios no processo de remo??o dos compostos BTEX. A rea??o catal?tica foi realizada durante 5h a 60 ?C, pH igual a 5,0, e as an?lises dos compostos foram feitas em um cromat?grafo a g?s com detec??o por fotoioniza??o de chama via headspace est?tico (HS-GC-PID). Os testes catal?ticos mostraram a efic?cia no uso deste tipo de catalisador para a remo??o desses compostos org?nicos vol?teis, apresentando uma taxa de remo??o na faixa de 90,60%, onde o catalisador em estudo foi o TiSBA-15(5,0)
7

Desenvolvimento de um amostrador passivo e o uso da fibra da Ceiba pentandra (L.) Gaertn como biosorvente de compostos org?nicos vol?teis - COVs do ar

Catunda, Ana Cl?a Marinho Miranda 11 April 2016 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-12-29T18:20:30Z No. of bitstreams: 1 AnaCleaMarinhoMirandaCatunda_TESE.pdf: 3985598 bytes, checksum: ced41c3c7c54212ab1644a8679629771 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-01-02T20:58:54Z (GMT) No. of bitstreams: 1 AnaCleaMarinhoMirandaCatunda_TESE.pdf: 3985598 bytes, checksum: ced41c3c7c54212ab1644a8679629771 (MD5) / Made available in DSpace on 2017-01-02T20:58:54Z (GMT). No. of bitstreams: 1 AnaCleaMarinhoMirandaCatunda_TESE.pdf: 3985598 bytes, checksum: ced41c3c7c54212ab1644a8679629771 (MD5) Previous issue date: 2016-04-11 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Os poluentes presentes na atmosfera, est?o principalmente relacionados ? grande emiss?o proveniente dos ve?culos automotivos e postos revendedores de combust?veis. O presente trabalho teve o objetivo de desenvolver um modelo de amostrador passivo e um biosorvente para Compostos Org?nicos Vol?teis - COVs espec?ficos para aplica??o em estudos de monitoramento ambiental da qualidade do ar. Neste trabalho foi avaliado o emprego de amostradores passivos para monitoramento ambiental de COVs e em especial o benzeno, devido seu alto grau de toxidade. A Ag?ncia Internacional de Pesquisa em C?ncer (International Agency for Research on Cancer - IARC/OMS) classifica o benzeno no Grupo 1, ou seja, como uma subst?ncia qu?mica com evid?ncias suficientes de sua carcinogenicidade em seres humanos. Os estudos de sor??o dos COVs, na fibra da Ceiba pentandra ativada constituinte dos amostradores passivos, foram realizados no Laborat?rio de Tecnologia Ambiental - LabTam da UFRN e em um posto revendedor de combust?veis na cidade de Natal?RN. As amostras foram analisadas utilizando um dessorvedor t?rmico acoplado a um cromat?grafo gasoso com detector de massa (CGMS). O m?todo de amostragem que utiliza amostradores passivos difusivos e a an?lise de COVs atrav?s do m?todo da pir?lise (CGMS) proposto neste trabalho, foi uma adapta??o do m?todo TO-17, da Ag?ncia de Prote??o Ambiental dos Estados Unidos - United States Enviromental Protection Agency. Este m?todo proposto permitiu identificar a presen?a dos compostos COVs no ar ambiente. A partir dos resultados obtidos em laborat?rio e em campo, correla??es emp?ricas foram propostas para correlacionar as concentra??es dos poluentes com as ?reas dos picos obtidos no CGMS. Esta correla??o proposta pode ser utilizada para obter bons resultados em diferentes locais e esta??es do ano. O biosorvente fibra da Ceiba pentandra ativada, confirmou atrav?s dos resultados da ?rea espec?fica (BET), temperatura de degrada??o (TG/DTG) e a hidrofobicidade do material, suas qualidades na amostragem de COVs do ar, que al?m de proteger o sistema analito de eventuais quantidades de ?gua, apresentou baixos n?veis de ru?do na faixa de elui??o estudada no CGMS. O m?todo de amostragem que utiliza amostradores passivos difusivos, permitiu identificar a presen?a de benzeno nos experimentos simulados no laborat?rio, como tamb?m, no ar ambiente. Diante dos resultados observados desta pesquisa, tecnologias ambientais inovadoras devem ser implementadas para contribuir com a redu??o dos riscos ocupacionais ocasionados pelos COVs, nas opera??es de abastecimento nos postos revendedores de combust?veis (PRCs) com o objetivo de proteger a sa?de dos trabalhadores frentistas. ? importante salientar que os resultados observados ao longo desta pesquisa devem ser encarados como indicativos e n?o conclusivos, pois um monitoramento maior se faz necess?rio para que conclus?es definitivas possam ser elaboradas. / Pollutants in the atmosphere are mainly related to large emission from the vehicles automotive and fuel service stations. This study aimed to develop a model of passive sampler and biosorbent for Volatile Organic Compounds - VOCs specific for application in environmental monitoring studies of air quality. This study evaluated the use of passive samplers for environmental monitoring of VOCs and benzene in particular, due to its high toxicity. The International Agency Research on Cancer (IARC/WHO) classifies benzene in the Group 1, that is as a chemical substance with sufficient evidence of its carcinogenicity in humans. Sorption studies of VOC in fiber Ceiba pentandra active constituent of passive samplers were held in the Laborat?rio de Tecnologia Ambiental- Labtam (UFRN) and a fuel service station in the city of Natal-RN. The samples were analyzed using a Thermal Desorption coupled to a gas chromatograph with a mass detector (GC/SM). The sampling method using diffusive passive samplers and VOC analysis through of pyrolysis method (GC/SM) proposed in this work, was an adaptation of the TO-17 method from the Environmental Protection Agency - United States Environmental Protection Agency. This proposed method allowed to identify the presence of VOC compounds in ambient air. From the results obtained in the laboratory and in the field, empirical correlations have been proposed to correlate the concentrations of the pollutants with the peak areas obtained from the GC/MS. This correlation proposal can be used to obtain good results in different locations and seasons. The biosorbent activated fiber Ceiba pentandra, confirmed by the results of the specific area (BET), degradation temperature (TG/DTG) and the hydrophobicity of the material, its qualities on the VOC sampling the air, which in addition to protecting the analyte system of any amounts of water, showed low noise levels in the elution range studied in the GC/SM. The sampling method which utilizes passive diffusive samplers allows identifying the presence of benzene in the simulated experiments in laboratory, but also in ambient air. Based on the results observed in this research, innovative environmental technologies should be implemented to contribute to the reduction of occupational hazards caused by VOC in the supply operations in fuel service stations in order to protect the health of gas station attendants. Importantly, the results observed during this research should be viewed as indicative and not conclusive, because one greater monitoring is needed so that definitive conclusions can be elaborated.
8

Predi??o da composi??o qu?mica do carv?o vegetal por espectrometria no infravermelho m?dio com reflect?ncia total atenuada de transformada de Fourier (ATR-FITR)

Bezerra, Rafaela Maria Ribeiro 16 December 2014 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-01-16T16:23:02Z No. of bitstreams: 1 RafaelaMariaRibeiroBezerra_DISSERT.pdf: 4712960 bytes, checksum: bd34e8939664916c328fed12e450c278 (MD5) / Approved for entry into archive by Elisangela Moura (lilaalves@gmail.com) on 2017-01-16T16:26:52Z (GMT) No. of bitstreams: 1 RafaelaMariaRibeiroBezerra_DISSERT.pdf: 4712960 bytes, checksum: bd34e8939664916c328fed12e450c278 (MD5) / Made available in DSpace on 2017-01-16T16:26:52Z (GMT). No. of bitstreams: 1 RafaelaMariaRibeiroBezerra_DISSERT.pdf: 4712960 bytes, checksum: bd34e8939664916c328fed12e450c278 (MD5) Previous issue date: 2014-12-16 / Funda??o de Amparo ? Pesquisa do Rio Grande do Norte (Fapern) / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / O objetivo do presente trabalho foi estimar os teores de carbono fixo, mat?rias vol?teis e cinzas no carv?o vegetal usando a reflect?ncia total atenuada com transformar de Fourier no infravermelho (FTIR-ATR), juntamente com os m?todos de calibra??o multivariada. V?rias t?cnicas de calibra??o multivariada, incluindo m?nimos quadrados parciais (PLS), intervalo de m?nimos quadrados parciais (IPLS), algoritmo gen?tico (GA), foram comparados e validados atrav?s do estabelecimento de teste de signific?ncia (teste t e teste de Shapiro-Wilk). Amostras de carv?o (n = 72) foram divididos em calibra??o (n = 52) e conjuntos de valida??o (n = 20), aplicando o algoritmo de sele??o cl?ssico Kennard-Stone (KS) para os espectros ATR-FTIR. Para teor de carbono fixo, o resultado obtido utilizando PLS-GA para o erro quadr?tico m?dio de valida??o cruzada (RMSECV) e previs?o (RMSEP) foram 3,77% e 4,29%, respectivamente. Para a mat?ria vol?til, RMSECV e RMSEP de 4,36% e 4,65% foi alcan?ada pelo modelo PLS utilizando sete vari?veis latentes (LV). Finalmente, para cinzas, RMSECV e RMSEP de 0,58% e 0,38%, foi alcan?ado pelo modelo PLS utilizando oito vari?veis latentes (LV). Foram realizados teste t e Quantil-quantil (Q-Q) plot para comparar os resultados dos modelos de uns com os outros e com um m?todo de refer?ncia. Estes resultados sugerem que a espectroscopia FTIR-ATR e calibra??o multivariada pode ser efetivamente usado para determinar os teores de carbono fixo, mat?ria vol?til e cinzas em carv?o vegetal brasileiro. / O objetivo do presente trabalho foi estimar os teores de carbono fixo, mat?rias vol?teis e cinzas no carv?o vegetal usando a reflect?ncia total atenuada com transformar de Fourier no infravermelho (FTIR-ATR), juntamente com os m?todos de calibra??o multivariada. V?rias t?cnicas de calibra??o multivariada, incluindo m?nimos quadrados parciais (PLS), intervalo de m?nimos quadrados parciais (IPLS), algoritmo gen?tico (GA), foram comparados e validados atrav?s do estabelecimento de teste de signific?ncia (teste t e teste de Shapiro-Wilk). Amostras de carv?o (n = 72) foram divididos em calibra??o (n = 52) e conjuntos de valida??o (n = 20), aplicando o algoritmo de sele??o cl?ssico Kennard-Stone (KS) para os espectros ATR-FTIR. Para teor de carbono fixo, o resultado obtido utilizando PLS-GA para o erro quadr?tico m?dio de valida??o cruzada (RMSECV) e previs?o (RMSEP) foram 3,77% e 4,29%, respectivamente. Para a mat?ria vol?til, RMSECV e RMSEP de 4,36% e 4,65% foi alcan?ada pelo modelo PLS utilizando sete vari?veis latentes (LV). Finalmente, para cinzas, RMSECV e RMSEP de 0,58% e 0,38%, foi alcan?ado pelo modelo PLS utilizando oito vari?veis latentes (LV). Foram realizados teste t e Quantil-quantil (Q-Q) plot para comparar os resultados dos modelos de uns com os outros e com um m?todo de refer?ncia. Estes resultados sugerem que a espectroscopia FTIR-ATR e calibra??o multivariada pode ser efetivamente usado para determinar os teores de carbono fixo, mat?ria vol?til e cinzas em carv?o vegetal brasileiro.
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Diagn?stico de contamina??o por derivado de petr?leo no solo e na ?gua subterr?nea em um terminal aquavi?rio: estudo de caso na cidade de Natal/RN

Lucas, Ana Carolina Mar?al Pires Ferreira 31 March 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2017-07-03T12:22:22Z No. of bitstreams: 1 AnaCarolinaMarcalPiresFerreiraLucas_DISSERT.pdf: 2241069 bytes, checksum: cc1d053944af95b14551bddf9de6e962 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2017-07-05T15:51:20Z (GMT) No. of bitstreams: 1 AnaCarolinaMarcalPiresFerreiraLucas_DISSERT.pdf: 2241069 bytes, checksum: cc1d053944af95b14551bddf9de6e962 (MD5) / Made available in DSpace on 2017-07-05T15:51:20Z (GMT). No. of bitstreams: 1 AnaCarolinaMarcalPiresFerreiraLucas_DISSERT.pdf: 2241069 bytes, checksum: cc1d053944af95b14551bddf9de6e962 (MD5) Previous issue date: 2017-03-31 / As Unidades de Terminais Aquavi?rios tem como fun??o principal receber, armazenar e distribuir petr?leo, derivados e combust?veis renov?veis l?quidos, garantindo o abastecimento dos mercados nacional e internacional. A grande movimenta??o log?stica gerada pela explora??o, beneficiamento, armazenagem, transporte e comercializa??o do petr?leo e seus derivados vem gerando preocupa??es relacionadas ? sua potencialidade de contamina??o do ambiente. Por causa dos in?meros acidentes com derramamento de combust?veis, os quais ocasionam contamina??es de solos e ?guas por hidrocarbonetos derivados de petr?leo, torna as pesquisas neste contexto um desafio para os profissionais que atuam na ?rea, em fun??o da complexidade de intera??es que ocorrem no solo e na ?gua. O Terminal, objeto de estudo, est? localizado na cidade de Natal-RN e ocupa uma ?rea de 110.000 m2. O estudo visa avaliar a contamina??o do solo e ?gua subterr?nea por derivados de petr?leo na bacia do tanque 1430-04, caracterizando a presen?a de subst?ncias com potencial de contamina??o atrav?s de dados obtidos pela coleta de amostras do solo e ?gua distribu?das para an?lise dos par?metros TPH fracionado, BTEX, VOC, SVOC e Metais. Como tamb?m, a an?lise dos par?metros f?sicos do solo (granulometria, porosidade total e efetiva, densidade de part?culas e total do solo, umidade natural) e fra??o de carbono org?nico. As an?lises qu?micas das amostras de solo n?o apresentaram concentra??es dos par?metros analisados (TPH, BTEX, VOC, SVOC e Metais). Nas amostras de ?gua subterr?neas foram detectadas concentra??es de benzeno, al?m de xilenos e TPH. Para os metais, foram detectados concentra??es de chumbo, al?m do ferro. J? para os metais dissolvidos apenas o chumbo apresentou concentra??es acima dos valores de investiga??o. Todos os resultados das an?lises qu?micas foram comparados com os valores da Resolu??o 420 do CONAMA de 2009. / The Aquavi?rios Terminal Unit's main function is to receive, store and distribute oil, oil products and liquid renewable fuels, ensuring the supply of domestic and international markets. The great logistic movement generated by the exploration, processing, storage, transportation and commercialization of oil and its derivatives has generated worries related to its potential contamination of the environment. Because of the numerous accidents with fuel spills, which cause contamination of soils and waters by oil-derived hydrocarbons, research in this context makes it a challenge for professionals working in the area, due to the complexity of interactions occurring in the soil and in the water. The Terminal, object of study, is located in the city of Natal-RN and occupies an area of 110,000 m2. The aim of this study is to evaluate soil and groundwater contamination by petroleum by-products in the 1430-04 basin, characterizing the presence of substances with potential contamination in soil and groundwater through the collection of soil and water samples for the analysis of TPH fractional parameters, BTEX, VOC, SVOC and metals. As well as the analysis of soil physical parameters (particle size, total and effective porosity, particle density and total soil, natural moisture) and organic carbon fraction. The chemical analyzes of soil samples did not present concentrations of the analyzed parameters (TPH, BTEX, VOC, SVOC and metals). Concentrations of benzene were detected in the groundwater samples, in addition to xylenes and TPH. For metals, concentrations of lead were detected in addition to iron. For dissolved metals, only lead had concentrations above the values investigated. All results of the chemical analyzes were compared with the values of CONAMA Resolution 420/2009.
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Design gr?fico da pluma de contamina??o por compostos org?nicos vol?teiss utilizando software CAD na investiga??o de passivo ambiental em um posto revendedor de combust?veis em Natal/RN

Aquino Sobrinho, Hercules Lisboa de 31 January 2011 (has links)
Made available in DSpace on 2014-12-17T14:08:48Z (GMT). No. of bitstreams: 1 HerculesLAS_DISSERT.pdf: 3304337 bytes, checksum: 041717a4cfd116130802eab3678923c7 (MD5) Previous issue date: 2011-01-31 / Among the potentially polluting economic activities that compromise the quality of groundwater are the gas stations. The city of Natal has about 120 gas stations, of which only has an environmental license for operation. Discontinuities in the offices were notified by the Public Ministry of Rio Grande do Norte to carry out the environmental adaptations, among which is the investigation of environmental liabilities. The preliminary and confirmatory stages of this investigation consisted in the evaluation of soil gas surveys with two confirmatory chemical analysis of BTEX, PAH and TPH. To get a good evaluation and interpretation of results obtained in the field, it became necessary three-dimensional representation of them. We used a CAD software to graph the equipment installed in a retail service station fuel in Natal, as well as the plumes of contamination by volatile organic compounds. The tool was concluded that contamination is not located in the current system of underground storage of fuel development, but reflects the historical past in which tanks were removed not tight gasoline and diesel / Dentre as atividades econ?micas potencialmente poluidoras que comprometem a qualidade das ?guas subterr?neas est?o os Postos Revendedores de Combust?veis. A cidade do Natal possui cerca de 120 postos de combust?veis, dos quais, apenas um possui licen?a ambiental de opera??o. Os postos em desconformidade foram notificados pelo Minist?rio P?blico do Rio Grande do Norte para realizarem as adequa??es ambientais, dentre as quais est? a investiga??o de passivo ambiental. As fases preliminar e confirmat?ria desta investiga??o consistiram na avalia??o de gases do solo com duas sondagens confirmat?rias para an?lises qu?micas de BTEX, HPA e TPH. Para obter-se uma boa avalia??o e interpreta??o dos resultados obtidos no campo, se fez necess?rio a representa??o tridimensional dos mesmos. Utilizou-se um software CAD para representar graficamente os equipamentos instalados em um posto revendedor de combust?vel em Natal/RN, assim como as plumas de contamina??o por compostos org?nicos vol?teis. A partir desta ferramenta foi poss?vel concluir que a contamina??o n?o est? localizada no atual Sistema de Armazenamento Subterr?neo de Combust?vel do empreendimento, mas reflete o hist?rico passado em que foram removidos tanques n?o estanques de gasolina e diesel

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