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Dissertations / Theses on the topic 'Centella'

Author: Grafiati

Published: 4 June 2021

Last updated: 4 February 2022

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1

Aziz, Zaleha Biniti A. "Tissue culture of Centella asiatica : asiaticoside biosynthesis." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368364.

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2

Silva, Frederico Pittella. "Caracterização fitoquímica e atividades biológicas de Centella asiática (L.) Urban." Universidade Federal de Juiz de Fora (UFJF), 2008. https://repositorio.ufjf.br/jspui/handle/ufjf/2913.

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Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-10-21T10:17:57Z No. of bitstreams: 1 fredericopitellasilvia.pdf: 5083140 bytes, checksum: 5be218953d7ca703da3fff1cbecea890 (MD5)<br>Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-10-25T12:30:40Z (GMT) No. of bitstreams: 1 fredericopitellasilvia.pdf: 5083140 bytes, checksum: 5be218953d7ca703da3fff1cbecea890 (MD5)<br>Made available in DSpace on 2016-10-25T12:30:40Z (GMT). No. of bitstreams: 1 fredericopitellasilvia.pdf: 5083140 bytes, checksum: 5be218953d7ca703da3fff1cbecea890 (MD5) Previous i

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3

Mangas, Alonso Susana. "Producción de saponinas triterpénicas en cultivos in vitro de "Centella asiatica"." Doctoral thesis, Universitat de Barcelona, 2009. http://hdl.handle.net/10803/2622.

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<i>Centella asiatica</i> es una planta medicinal usada fundamentalmente para el tratamiento de afecciones de la piel como la cicatrización de heridas, tratamiento de la dermatitis o celulitis, etc. Problemas de índole geopolíticos y alteraciones en su hábitat han provocado un desabastecimiento del mercado de esta planta. Por todo ello, es necesario el desarrollo de procesos alternativos como los sistemas biotecnológicos, para conseguir la producción <i>in vitro</i> de centellósidos. En esta tesis se ha desarrollado inicialmente un sistema de micropropagación vegetal de <i>C. asiatica</i> media

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4

鄭全龍 and Chuen-lung Cheng. "The anti-ulcer mechanisms of Centella Asiatica and Asiaticoside on gastric ulceration." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B43894549.

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5

Cheng, Chuen-lung. "The anti-ulcer mechanisms of Centella Asiatica and Asiaticoside on gastric ulceration." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22786399.

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6

Ichoku, Emmanuel. "Isolation and Bioassay evaluation of Angiotensin Converting Enzyme inhibitory compounds of Centella asiatica." University of the Western Cape, 2019. http://hdl.handle.net/11394/7322.

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Magister Pharmaceuticae - MPharm<br>Hypertension is by far the most common risk factor for cardiovascular disease (CVD), which has been identified as the leading cause of death worldwide and a major economic burden in developing countries. Over the years, there has been an increased interest in isolating and identifying bioactive compounds from medicinal plant, with the aim of finding alternative sources of therapy to some of the problematic synthetic drugs and to validate the therapeutic use of some traditional plants. The renin angiotensin aldosterone system is a key regulator of blood press

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7

Petit, Virginie. "Valorisation phytochimique et biologique de plantes tropicales." Thesis, Pau, 2016. http://www.theses.fr/2016PAUU3016.

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Ce mémoire de thèse confidentiel porte sur la valorisation phytochimique et biologique de plantes tropicales. Il s’inscrit dans le cadre d’une procédure de validation des acquis de l’expérience et retrace 14 ans de travaux de recherche appliquée pour la mise sur le marché de nouveaux actifs végétaux destinés à l’industrie dermo cosmétique ainsi que des recherches fondamentales. Ce travail a permis le développement de nouveaux actifs, à forte valeur ajoutée, issus de plantes de Madagascar par la valorisation de nombreux métabolites secondaires tels que les polyphénols (flavonoïdes, tannins, dér

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8

Rocha, Priscila Bianca Rodrigues da. "Desenvolvimento de carreadores lipídicos nanoestruturados contendo extrato de Centella asiatica (L.) Urban para uso tópico." Universidade Federal de Goiás, 2015. http://repositorio.bc.ufg.br/tede/handle/tede/6691.

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Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2017-01-05T09:37:46Z No. of bitstreams: 2 Dissertação - Priscila Bianca Rodrigues da Rocha - 2016.pdf: 3342071 bytes, checksum: 4810677b5ff246d6d0dd384d773187fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)<br>Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2017-01-05T10:33:16Z (GMT) No. of bitstreams: 2 Dissertação - Priscila Bianca Rodrigues da Rocha - 2016.pdf: 3342071 bytes, checksum: 4810677b5ff246d6d0dd384d773187fd (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9

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9

Wijeweera, Priyantha. "Phytochemical basis for the anxiolytic activity of the ayurvedic medicinal plant Centella asiatica (L) Urb (gotukola)." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26349.

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Gotukola (Centella asiatica L. Urban) (Apiaceae), its extracts and the pure compound asiaticoside were studied for anxiolytic activity in thirteen standardized rat trials. High performance liquid chromatography (HPLC) was used to conduct the phytochemical analysis. Among different models tested, the most promising positive response for anxiolytic activity was observed in the elevated plus maze test conducted with: (a) whole plant materials, (b) ethyl acetate and methanol fractions and (c) asiaticoside. The results show for the first time that asiaticoside and triterpene enriched fractions of g

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10

Marques, Naiani Ferreira. "Centella asiática REDUZ PEROXIDAÇÃO LIPÍDICA INDUZIDA POR ÁCIDO QUINOLÍNICO E NITROPRUSSIATO DE SÓDIO IN VITRO EM REGIÕES DO CÉREBRO DE RATO." Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/11242.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>The oxidative stress is envolved in several diseases, including neurological diseases. Centella asiatica is a medicinal plant which was has long been used to treat neurological disturbances in Ayurvedic medicine. The aim of this study was to evaluate the antioxidant potencial of different extracts of C.asiatica in vitro. Were quantified by High Performance Liquid Chromatograph (HPLC) the present compounds and examined the phenolic content of the infusion and fractions: ethyl acetate, n-butanol and dichlorometane. Furthermore, the a

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11

Costa, Fernanda de. "Saponinas triterpênicas:biossíntese e atividade biológica." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/106409.

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Saponinas triterpênicas incluem uma ampla variedade de moléculas com diversas aplicações farmacológicas. As saponinas das folhas de Quillaja brasiliensis, espécie nativa do Sul do Brasil, são estrutural e funcionalmente semelhantes às encontradas nas cascas da espécie chilena Quillaja saponaria, as quais são utilizadas atualmente como adjuvantes em formulações comerciais de vacinas. O perfil de acúmulo da fração imunoadjuvante de saponinas triterpênicas de Q. brasiliensis (QB-90) foi avaliado em resposta a diferentes fatores de estresse. O conteúdo de QB-90 em discos foliares aumentou signific

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12

Solet, Jean-Michel. "Mécanismes de biotransformation de la thiocolchicine par une suspension cellulaire de "Centelia asiatica" L : démethylation et glucosylation : étude de la glucosyltransférase." Paris 11, 1993. http://www.theses.fr/1993PA114827.

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13

Saibu, Olusola Surajudeen. "Analysis of three wetland medicinal plants: Centella asiatica, Cyperus longus and Typha capensis found in the Western Cape Province of South Africa." University of the Western Cape, 2017. http://hdl.handle.net/11394/6356.

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Magister Scientiae (Biodiversity and Conservation Biology)<br>South Africa is recognised worldwide for its rich diversity of plants, many of which have been used in ethno-medicine. However, the use of wetland plant species in ethno-medicine required further investigations. This research is aimed at investigating three wetland medicinal, plant species, Centella asiatica, Cyperus longus and Typha capensis based on their geographical, seasonal, mineral nutrient (Fe, Mn, Ca, Mg, K and Na) and secondary metabolite characteristics. Samples of each species were collected from Grabouw, Kelderhoff, Ken

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14

Tran, Xuan Tiep. "Využití kapilární elektroforézy pro stanovení vybrané skupiny flavonoidů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-449372.

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In recent years, the use of natural medicinal properties of plants has again come to the forefront of interest of the public. Because of their therapeutic properties, these plants are commonly used in alternative treatments for minor ailments. This thesis deals with the determination of polyphenolic acids in extracts from aronia, echinacea, tetradenia and centella. One of the aims of the thesis was to compare the amount of polyphenolic acids in individual plants with their antioxidant properties. The theoretical part includes a general introduction to flavonoids, introduction to polyphenolic a

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15

Müller-Keilholz, Viola [Verfasser]. "Relevance of mineral nutrition and light quality for the accumulation of secondary metabolites in Centella asiatica and Hydrocotyle leucocephala / Viola Müller." Bonn : Universitäts- und Landesbibliothek Bonn, 2014. http://d-nb.info/1047666553/34.

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16

BOUHOUCHE, NAIMA. "Glucosylation de la 3-demethylthiocolchicine par une suspension cellulaire de centella asiatica : caracterisation et purification de la glycosyltransferase (doctorat : structure et fonctionnement des systemes biologiques integres)." Paris 11, 1998. http://www.theses.fr/1998PA114819.

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17

Voigt, Robert L., David K. Parsons, Carl L. Schmalzel, Julianne Henderson, and Ann M. Tinsley. "Popcorn Production in South Centerl Arizona. 1984." College of Agriculture, University of Arizona (Tucson, AZ), 1985. http://hdl.handle.net/10150/200473.

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18

Scandura, C. M. "Estudo de otimização do rendimento volumétrico de um motor de combustão por centelha/." reponame:Biblioteca Digital de Teses e Dissertações da FEI, 2017. https://doi.org/10.31414/EM.2017.D.129045.

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19

Pujatti, Fabricio Jose Pacheco. "Desenvolvimento de um sistema de gerenciamento eletrônico para motores de ignição por centelha." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/SBPS-7B6KA6.

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Since the conception and first built of internal combustion engine (ICE), many control intake fuel systems and spark systems are being developed. The inclusion of electronic control systems enables to optimize their efficiency, reducing the vehicle environmental impact. The task of calibration and adjustment, to this optimization, needs to electronic management systems called Electronic Computer Unit (ECU). Although exist many different manufactures, it has a high cost and an access level incompatible with the needs of an independent research group. This work are intend to design, build and te

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20

Galib, Flavio 1953. "Analise do desempenho de um motor de ignição por centelha, alimentado com alcool etilico pre-vaporizado." [s.n.], 1988. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265518.

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Orientadores : Raymond B. Peel ; Kamal A. R. Ismail<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Campinas<br>Made available in DSpace on 2018-07-15T12:29:26Z (GMT). No. of bitstreams: 1 Galib_Flavio_M.pdf: 10049648 bytes, checksum: c6ceaeeb13eb73eb301046f2850b023f (MD5) Previous issue date: 1988<br>Resumo: O presente trabalho tem, por objetivo, apresentar os resultados do desempenho de um motor MONZA (cilindrada 1.6 1, taxa de compressão 12:1) alimentado com álcool etílico pré-vaporizado. Foram feitas análises comparativas do ensaio do mesmo motor

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21

Cró, Nelson Prado Rodrigues 1985. "Modelo para simulação computacional do ciclo termodinâmico de motores de combustão interna com ignição por centelha." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/265911.

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Orientador: Janito Vaqueiro Ferreira<br>Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica<br>Made available in DSpace on 2018-08-25T19:22:38Z (GMT). No. of bitstreams: 1 Cro_NelsonPradoRodrigues_M.pdf: 2904462 bytes, checksum: 1e944d316e2e4ec4ca0a4e8ba01ae4a2 (MD5) Previous issue date: 2014<br>Resumo: Este trabalho descreve o desenvolvimento de um modelo de simulação computacional para motores de combustão interna com ignição por centelha que inclui o processo de combustão com duração finita, a transferência de calor instantânea entre o fluído opera

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22

Andreoli, Alexandre Giordani. "Análise e simulação de mapas base de injeção eletrônica de combustível para motores de ignição a centelha." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/75756.

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Uma nova metodologia para a criação de mapas base de injeção eletrônica de combustível para motores de combustão interna de ignição a centelha é apresentada e seu comportamento é comparado com os resultados fornecidos pela metodologia MVEM. A partir da utilização de equacionamentos da literatura, é feita uma modelagem do ciclo ideal Otto para um motor genérico alternativo monocilíndrico de 500 cm³ de volume deslocado. É modelada também uma válvula do tipo borboleta genérica de 0,06 m³ de diâmetro que opera tanto em regime subsônico quanto sônico. A pressão à jusante da borboleta é calculada pa

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23

Aguilar, Uribe Israel. "Desarrollo de un detector de radiación gamma basado en un material orgánico centello-gráfico para imagen nuclear." Tesis de maestría, Universidad Autónoma del Estado de México, 2019. http://hdl.handle.net/20.500.11799/105545.

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En este proyecto se desarrolló un detector compacto de fotones gama para imagen nuclear a través de un arreglo de plásticos centello gráficos y un tubo fotomultiplicador sensible a la posición, mejorando su resolución y la eficiencia de detección reduciendo el espacio ocupado por el equipo.<br>Introduction. A conventional gamma camera consists of a scintillator material coupled to a photomultiplier tube. It transforms the photons of incident electromagnetic radiation into a signal that is then processed to show the distribution of the radioactive material within the patient. A functional image

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24

Martelli, André Luiz. "Análise da combustão do gás natural em um motor a pistão de ignição por centelha e injeção direta." Instituto Tecnológico de Aeronáutica, 2012. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2285.

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O gás natural vem ganhando espaço na matriz energética mundial, com crescente participação no setor de transportes. Sua utilização em motores de combustão interna traz vantagens quanto à emissão de gases nocivos e à redução do nível de ruído, em comparação ao combustível diesel. Tradicionalmente, o gás é injetado no coletor de admissão, porém existem pesquisas e até mesmo aplicações comerciais de sistemas com injeção direta de combustível gasoso na câmara de combustão. Entre os ganhos potenciais da injeção direta destacam-se o desempenho (pela elevação da eficiência volumétrica do motor) e a p

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25

Braga, Gabriel Teixeira. "Uma contribuição ao controle de motores de combustão interna de ignição por centelha na condição de marcha lenta." Universidade Federal de Minas Gerais, 2007. http://hdl.handle.net/1843/BUOS-8D7HKR.

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The present work is placed in the context of an open Electronic Control Unit (ECU) development, intended to supply the lack of a flexible control system that favors research development in the engine area. After the ECU's hardware architecture definition in a previous work, was defined as objective of the present work the development of a complete strategy of injection, ignition and speed control of an Internal Combustion Engine (ICE) in the idle condition. In this condition the engine is not accelerated, and in this way must be kept by ECU in the lesser possible speed to minimize consumption,

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26

Sari, Rafael Lago. "Avaliação da utilização de etanol com elevados teores de água em motores de combustão interna com ignição por centelha." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/158246.

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A utilização de combustíveis fósseis é percebida, cada vez mais, de forma negativa, visto seus elevados níveis de emissão de gases de efeito estufa. Por conta disso, busca-se a ampliação do uso de combustíveis de origem renovável de forma a diminuir o impacto ambiental. Dentre esses, o etanol se destaca pelas excelentes características físico-químicas. Ao se reduzir o nível de pureza (diluição em agua) durante o processo de destilação desse combustível, obtém-se um sensível decréscimo da energia dispendida na sua produção. Isso se deve ao crescimento exponencial do consumo energético para obte

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27

Silva, Sylvana Kelly Marques da. "Centelhas de uma cidade tur?stica nos cart?es-postais de Jaeci Galv?o (1940-1980)." Universidade Federal do Rio Grande do Norte, 2012. http://repositorio.ufrn.br/handle/123456789/21110.

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Bergel, André. "Numerical analysis of exhaust gas aftertreatment in spark ignition engines." Instituto Tecnológico de Aeronáutica, 2014. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=3146.

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This dissertation describes the known formation mechanisms of pollutant emissions for spark ignition internal combustion engines, the most common pollutants emitted by spark ignition engines, current methods to reduce pollutants emissions and a comparison of industry procedures with one and three-dimensional modeling including detailed surface reaction chemistry model, all used to estimate catalytic converter efficiency. Also, experimental tests were performed to provide exhaust gas composition boundary conditions, and to provide values for current catalytic converter efficiency. The detailed

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Soler, Molina Joan Abel. "Intervenció senyorial i transformacions locals a la baronia de Rebollet-comtat d'Oliva (segles XIII-XVI). Els Carròs i els Centelles." Doctoral thesis, Universidad de Alicante, 2020. http://hdl.handle.net/10045/115561.

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L'expansió de la societat feudal sobre l'Àndalus en el segle XIII derivà en la conformació de senyories territorials al regne de València, constituït aleshores pel Jaume I d'Aragó. El rei Conqueridor atorgà el feu de Rebollet (1240) a un corsari ennoblit per ell mateix, el lígur Carroccio di Alamanno da Costa (Carròs), que s'ocupà d'assentar colons cristians al castell de Rebollet i a la futura vila d'Oliva, vora la qual instal·là una poblada Moreria. Com ell, el seus successors en l'"honor" de Rebollet (baronia des del 1330, amb mer i mixt imperi) destacaren en les guerres d'expansió meditarr

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Ríos, Quiroga Luis Carlos [UNESP]. "Avaliação da relação entre a energia de ativação e a energia útil para diferentes misturas de etanol e gasolina aplicados a motores de ignição por centelha." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/146676.

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Rios, Quiroga Luis Carlos. "Avaliação da relação entre a energia de ativação e a energia útil para diferentes misturas de etanol e gasolina aplicados a motores de ignição por centelha /." Guaratinguetá, 2016. http://hdl.handle.net/11449/146676.

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Orientador: Ivonete Ávila<br>Coorientador: José Antonio Perrella Balestieri<br>Banca: José Alexandre Matelli<br>Banca: Alex Mendonça Bimbato<br>Banca: Greta Larisa Aurora Arce Ferrufino<br>Banca: Délson Luiz Módulo<br>Resumo: A aplicação do etanol como combustível ou como aditivo misturado à gasolina é muito importante para a maioria dos países que procuram reduzir a dependência dos combustíveis fósseis e mitigar os gases de efeito estufa. O uso cada vez maior de misturas de etanol e gasolina torna cada vez mais relevante o conhecimento de suas propriedades físicas e químicas, de forma a favor

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Santos, Dinarte. "Modelo termodinâmico para a simulação do ciclo de motores de ignição por centelha / Dinarte Santos ; orientador, José Antonio A. Velásquez Alegre ; co-orientador, Irionson Antônio Bassani." reponame:Biblioteca Digital de Teses e Dissertações da PUC_PR, 2010. http://www.biblioteca.pucpr.br/tede/tde_busca/arquivo.php?codArquivo=2032.

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Dissertação (mestrado) - Pontifícia Universidade Católica do Paraná, Curitiba, 2010<br>Bibliografia: f. 103-105<br>Este trabalho descreve o desenvolvimento e a implementacao de um modelo de duas zonas de combustao que permite simular os processos que compoem o ciclo de trabalho dos motores de ignicao por centelha, incluindo os processos de compressao, combustao-expans<br>This M. Sc. thesis describes the development of a two-zone combustion model, which allows simulating the working cycle processes of a spark ignition engine, including the compression process, the combustion-expansion process,

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Hindi, Gustavo de Queiroz. "3D numerical investigation of mixture formation and combustion in a DISI engine at part-load under stratified operation." Instituto Tecnológico de Aeronáutica, 2011. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2022.

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This work investigates through numerical simulation, the operation of a big bore direct fuel injection spark ignition engine, at part load under stratified operation. It evaluates fuel-air mixture preparation and combustion process with the adoption of detailed chemical kinetics mechanisms for both Isooctane and Ethanol, and applying adaptive mesh refinement to capture the turbulent flame brush. The investigation is split in 3 main parts. In the first part, with Isooctane as fuel, the impact of in-cylinder turbulence level induced by squish has shown that the attempt to isolate the squish rati

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Goulart, Bruno Santos. "Estudo experimental de sistemas de ignição de alta voltagem e energia para uso veicular." Instituto Tecnológico de Aeronáutica, 2013. http://www.bd.bibl.ita.br/tde_busca/arquivo.php?codArquivo=2764.

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Uma combustão eficiente depende de muitos fatores, tais como injeção de combustível, turbulência e características de ignição. Com a melhoria dos motores de combustão interna a intensidade de turbulência e a pressão interna vêm aumentando, demandando com isso sistemas de ignição mais potentes e eficientes. Em motores de injeção direta, as cargas estratificadas resultantes do spray direto guiado por fronteiras ou ainda por escoamento requerem ainda mais energia. Neste trabalho foi investigado o efeito de diversos parâmetros de ignição nos fenômenos elétricos e mecânicos ligados à abertura e sus

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Ávila, Márcio Turra de. "Estudo de um motor regenerativo, do ciclo Otto, movido a etanol previamente vaporizado." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-09102015-155527/.

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O álcool etílico ou etanol vem se tornando, neste novo século, uma importante referência para estudos e aplicações que procuram um combustível alternativo ao uso de derivados de petróleo em motores de combustão interna. Neste trabalho, o uso do etanol vaporizado pelos gases de escape em motores do ciclo Otto busca a obtenção de melhores níveis de rendimento térmico e emissões de poluentes. Assim sendo, um motor de 1.0 litro foi montado em laboratório com um trocador de calor instalado ao lado do coletor de escapamento, e uma série de testes foram feitos, possibilitando uma cuidadosa análise qu

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Ejerås, Anne. "Föräldrars erfarenheter av gruppträffar på barnavårdscentralEn tvärsnittsudie med mixad metod : Parent´s experiences of group meetings at child health centerA cross-sectional study with mixed method." Thesis, Mittuniversitetet, Avdelningen för omvårdnad, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-30981.

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Ferré, Panisello M. Teresa. "Agustí Centelles i Ossó (1909–1985), de la jove promesa del fotoperiodisme als anys trenta fins al mite unívoc del fotògraf de la Guerra Civil construït durant la Transició." Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/672051.

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L’objectiu principal d’aquesta tesi doctoral ha estat traçar la biografia professional del fotògraf Agustí Centelles (1909-1985). Una carrera extensa que, globalment, es desenvolupà durant pràcticament mig segle: des dels anys vint del segle passat, fins a finals de la dècada dels 70. Centelles culminà la seva carrera com a fotoperiodista i es convertí en referent durant la Guerra Civil espanyola. Posteriorment es transformà en documentalista mentre estava detingut al camp de concentració de Bram el 1939, experiència de la qual en deixà un llegat fotogràfic excepcional en la visualització del

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Ávila, Márcio Turra de. "Estudo de motor de combustão interna, do Ciclo Otto, movido a etanol previamente vaporizado." Universidade de São Paulo, 1994. http://www.teses.usp.br/teses/disponiveis/18/18135/tde-09102015-153544/.

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O etanol (álcool etílico) tem sido cada vez mais estudado e testado como combustível alternativo para substituição do uso de alguns derivados de petróleo em motores de combustão interna. O presente trabalho procura abordar o emprego do etanol na forma vaporizada em motores do ciclo Otto, objetivando a obtenção de melhores níveis de rendimento térmico total. Deste modo, um motor para teste de octanagem (motor CFR) foi equipado com um vaporizador de álcool instalado no coletor de escapamento, e após uma série de ensaios, várias análises puderam ser feitas. Essas considerações procuraram se ater

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Fagundez, Jean Lucca Souza. "Avaliação energética do uso de álcoois combustíveis em motores de combustão interna." Universidade Federal de Santa Maria, 2016. http://repositorio.ufsm.br/handle/1/10624.

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The present work studies the use of a two-zone computer model to simulate the operation of an internal combustion engine with spark ignition fueled with alcohol fuels and gasohol. To fit the model to the experimental data, a parameter estimation technique was used and the heat transfer correlation that could better fit the tested fuels and engine was determined. The tested fuels were: hydrous ethanol, wet ethanol (from 10% to 40% of water, by volume), n-butanol, n-butanol/ethanol blend and gasohol. In addition to the experimental tests with the engine, tests with a packed distillation column u

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Locubiche-Serra, Sergi. "Robust Carrier Tracking Techniques for GNSS Receivers affected by Ionospheric Scintillation." Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/668304.

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Las tecnologías de posicionamiento por satélite (GNSS, del inglés global navigation satellite systems) se han convertido en una herramienta indispensable en diferentes ámbitos de nuestra sociedad moderna. Algunos ejemplos de aplicaciones son el posicionamiento y la navegación en entornos terrestre, marítimo y aéreo, así como usos destinados a la agricultura, topografía o aplicaciones de sincronización precisa en sistemas de telecomunicaciones o finanzas. El módulo de tracking es una de las etapas centrales para mantener los receptores alineados con los satélites, y hasta ahora se han empleado

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Sánchez, Góez Sebastián. "Algoritmo de reconstrucción analítico para el escáner basado en cristales monolíticos MINDView." Doctoral thesis, Universitat Politècnica de València, 2021. http://hdl.handle.net/10251/159259.

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[ES] La tomografía por emisión de positrones (PET, del inglés Positron Emission Tomography) es una técnica de medicina nuclear en la que se genera una imagen a partir de la detección de rayos gamma en coincidencia. Estos rayos son producidos dentro de un paciente al que se le inyecta una radiotrazador emisor de positrones, los cuales se aniquilan con electrones del medio circundante. El proceso de adquisición de eventos de interacción, tiene como unidad central el detector del escáner PET, el cual se compone a su vez de un cristal de centelleo, encargado de transformar los rayos gamma incident

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Wen, Wen-Terng, and 葉文騰. "The Application of Centella Asiatica Extraction in Cosmetic." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/16811582404375159675.

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碩士<br>國立海洋大學<br>食品科學系碩士在職專班<br>91<br>The purpose of the study is to explore the application of four active components (asiaticoside, asiatic acid, madecassoside and madecassic acid), the derivatives of pentacyclic triterpene, extracted from Asiatic Pennyworth, as anti-skin aging, anti-wrinkle ingredients in cosmetics. The study includes 3 parts, Part I：Identification of the four active components extracted from different growth places and different part of the Asiatic pennyworth. with different solvents. Each extract obtained was characterized by HPLC for determining the molecular weight of t

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Schubert, Mahalia Theresia Reina. "A revision of the genus Centella L. (Apiaceae)." Thesis, 2014. http://hdl.handle.net/10210/10914.

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D.Phil. (Botany)<br>A taxonomic revision of the genus Centella is presented that is based on vegetative and reproductive characters. Genetic data was included in the extensive research ofpossible hybridisation. Hybridization as a possible mechanism of evolution may account for the lack of conguence between taxonomic characters in Centella. Phylogenetic and phenetic methods of analysis were used to explore the relationships among species. The results show that Centella is a particularly difficult genus, with many ofthe problems experienced at species level being a reflection ofthe problematic n

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Booncong, Prakongsiri. "A pharmacognostic and taxonomic study of Centella asiatica (Apiaceae) /." 1989. http://www.gbv.de/dms/bs/toc/128387602.pdf.

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James, Jacinda Terry. "Determination and manipulation of biologically active triterpenoid secondary metabolites in Centella asiatica." Thesis, 2013. http://hdl.handle.net/10210/8537.

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D.Phil. (Biochemistry)<br>Plants are able to recognise and respond to signals from the environment through a complex array of biochemical pathways, which enables them to deter pathogenic micro-organisms and herbivores. Thousands of different structures of low-molecular weight organic compounds / natural products can be produced through an inducible chemical defence system; that can be manipulated for biotechnological purposes. The importance of natural products in medicine, agriculture and industry has led to numerous studies such as this, to understand the biosynthesis and biological activity

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Yeh, Jen-Yu, and 葉人與. "Application and Evaluation of Electrospinning Gelatin Nanofiber Combined with Centella asiatica for Skin Tissue Engineering." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/92988473663590895549.

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碩士<br>中臺科技大學<br>醫學工程暨材料研究所<br>98<br>The objective of this study is to prepare Gelatin/PVA/Asiaticoside nanofibers via electrospinning as a novel membrane. Gelatin nanofiber added with the active component of Centella asiatica through electrospinning technique was used to simulate as an extracellular matrix. From the cell co-culture experiments including MTT assay, light microscopy observation, it is found that the structure of nanofiber could enhance cell adhesion and proliferation. The optimal concentration of Centella asiatica extract at 156 μg/ml was added into Gelatin/PVA solution during

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Florczak, Melissa Claudia. "Extraction and characterisation of the essential oil from Centella Asiatica (Pennywort) growing in South Africa." Thesis, 2014. http://hdl.handle.net/10539/18547.

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A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Master of Science. Johannesburg, 2014.<br>Aromatic plants and oils have been used for thousands of years in perfumes, and cosmetics and for their culinary and medicinal purposes. The essential oil from Centella Asiatica growing specifically in South Africa has many therapeutic uses and is used to treat various diseases. Different extraction methods were used on the leaves of Centella Asiatica and the composition of each sample of oil obtained w

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Dwarka, Depika. "Anti-carcinogenic activity of Centella asiatica and Elytropappus rhinocerotis on a human colon cancer cell line." Thesis, 2012. http://hdl.handle.net/10321/705.

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Submitted in complete fulfillment for the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2012.<br>Recently our understanding of cancer has advanced in the realization that apoptosis and the genes that control it have a profound effect on the malignant phenotype. It is now clear that some oncogenic mutations disrupt apoptosis, leading to tumor initiation, progression or metastasis. Conversely, compelling evidence indicates that other oncogenic changes promote apoptosis, thereby producing selective pressure to override apoptosis during multistage carcinogenesis.

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Huang, Yen-Han, and 黃彥涵. "Effect of different rates of nitrogen fertilizer on the nutrient, yield and centelloside concentration of Centella asiatica." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/01172499007025035626.

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碩士<br>國立臺灣大學<br>農業化學研究所<br>99<br>Abstract Theactive metabolites of Centella asiatica, centelloside, could improve synthesis of collagen, treat some skin diseases and enhance learning and memory. It could be a drug used after brain attack and epilepsy. C. asiatica is a herbaceous annual plant, having creeping stolons with a low biomass yield. Therefore, high biomass yield and high concentration of centelloside are very important in order to use this plant. The study was conducted in the green house of National Taiwan University with two types of culture, i.e., soil culture and water culture. Al

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I-Chen, Wu, and 吳宜真. "Effects of Different Nitrogen Fertilizers and Application Rates on the Growth and Physiological-nutrition of Centella asiatica (L.) Urban." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/57329218331901156883.

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碩士<br>國立臺灣大學<br>農業化學研究所<br>92<br>Abstract It is convenient and important for using synthetic drugs in medical science today, however, there is still an increasing demand for natural products which come from plants or microorganism. Because of increment of quantity demanded, cultivation becomes an important way to obtain and control the quality of the medical plants. The objective of this study was to investigate the effects of different kinds and rates and nitrogen fertilizers on the growth and physiological-nutrition of Centella asiatica (L.) Urban in pot culture. The experiment was conducte

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