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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Die Bedeutung von "Peroxisome Proliferator-Activated Receptors" in der Pathogenese von Gefäßwandläsionen und ihr Einfluß auf die Migration und Proliferation vaskulärer Zellen

Götze, Stephan 05 May 2003 (has links)
Die Migration und Proliferation vaskulärer Zellen spielt eine entscheidende Rolle in der Pathogenese atherosklerotischer Gefäßwandveränderungen und trägt zudem in hohem Maße zu restenosebedingten Komplikationen interventioneller Therapien der Atherosklerose bei. Dies bedingt ein großes Interesse an pharmakologischen Interventionsmöglichkeiten zur Prävention / Therapie atherosklerotischer und restenotischer vaskulärer Läsionen. Dabei kommen neben lokal applizierbaren Substanzgruppen insbesondere Pharmaka in Betracht, die bereits Anwendung zur Behandlung metabolischer Risikofaktoren kardiovaskulärer Erkrankungen finden. Hierzu gehören insbesondere die oralen Antidiabetika vom Typ der Thiazolidindeone, die als Liganden für den "Peroxisome Proliferator-Activated Receptor gamma" (PPARg) agieren. PPARs sind eine Gruppe neuer Regulatoren der Genexpression, für die in den vergangenen Jahren eine Reihe vaskulärer Wirkungen nachgewiesen wurden. Wir konnten zeigen, daß die Proliferation und Migration von Gefäßmuskelzellen durch PPARg-Liganden gehemmt wird. Untersuchungen zu den beteiligten Signalübertragungsschritten ergaben, daß die pharmakologische Aktivierung von PPARg in Gefäßmuskelzellen insbesondere die durch die Mitogen-aktivierten Protein Kinasen ERK1/2 vermittelte Signaltransduktion beeinflußt. Diesbezüglich haben wir nachgewiesen, daß PPARg in Gefäßmuskelzellen die mitogene Signaltransduktion via ERK1/2 MAPK -> Elk-1 -> c-fos und die chemotaktische Signalübertragung via ERK1/2 MAPK -> Ets-1 -> Matrixmetalloproteinase-9 hemmt. Wir konnten ferner zeigen, daß PPARg-Liganden die Endothelzellmigration hemmen, die durch die Neovaskularisation atherosklerotischer Plaques und der damit verbundenen erhöhten Vulnerabilität einer Plaqueruptur eine Rolle in der Pathobiologie der Atherosklerose spielt. Diese migrationshemmende Wirkung der PPARg-Liganden basiert vermutlich auf einer Inhibition der für die Endothelzellmigration erforderlichen Signaltransduktion über den PI3 Kinase -> Akt -> eNOS Pathway. Die Inhibition dieses Signalwegs könnte die Folge der von uns beobachteten PPARg-Ligand-induzierten Expression der Phosphatase PTEN sein, die den PI3K -> Akt Signalweg negativ reguliert und die Aktivierung und Phosphorylierung von Akt inhibiert. Somit haben PPARg-aktivierende Liganden eine wichtige Funktion in der Behandlung der metabolischen Hauptrisikofaktoren kardiovaskulärer Erkrankungen, spielen aber gleichzeitig eine vermutlich ebenso wichtige Rolle in der Protektion atherosklerotischer und restenosebedingter Gefäßwandveränderungen durch direkte vaskuläre Effekte. / Migration and proliferation of vascular cells not only play an important role in the pathogenesis of atherosclerotic lesion formation, but also contribute to restenosis after therapeutic angioplasty. Therefore, pharmacological strategies for the prevention and/or treatment of atherosclerotic and restenotic vascular lesions are of great clinical interest. This involves substances that can be locally administered via stents, as well as agents that are already in clinical use for the treatment of metabolic risk factors. Among the latter, antidiabetic thiazolidinediones which function as ligands for the "peroxisome proliferator-activated receptor gamma" (PPARg), have been identified as promising drugs to target vascular lesion formation. PPARs constitute a group of novel regulators of gene expression, that exert several vascular effects. We report that vascular smooth muscle cell proliferation and migration is inhibited by PPARg-ligands. Investigating the signalling steps that are involved, we find that pharmacological activation of PPARg interferes with signal transduction through the mitogen-activated protein kinases ERK1/2 in vascular smooth muscle cells. We demonstrate that PPARg inhibits mitogenic signal transduction via ERK1/2 MAPK -> Elk-1 -> c-fos and also blocks chemotactic signalling through the ERK1/2 MAPK -> Ets-1 -> matrix metalloproteinase-9 pathway in vascular smooth muscle cells. We also showed that PPARg-ligands inhibit endothelial cell migration, which participates in the neovascularization of atherosclerotic plaques, thereby contributing to plaque destabilization and increased risk of plaque hemorrhage. This antimigratory action of PPARg-ligands results from an inhibition of signal transduction via PI3 Kinase -> Akt -> eNOS, a pathway that is crucial for endothelial cell migration. Since we observed a PPARg-ligand-induced upregulation of PTEN, a phosphatase that negatively regulates the PI3K -> Akt signalling pathway, this might constitute the mechanism by which PPARg-ligands inhibit endothelial cell migration. In conclusion, PPARg-activating ligands may provide a dual benefit in cardiovascular disease by ameliorating metabolic risk factors, as well as protecting the vasculature from atherosclerotic and restenotic alterations through direct vascular effects.
112

Matteo Ricci’s Xiqin Quyi – A Jesuit’s Expert Musicking in Ming China

Wong, Tsz 20 November 2017 (has links)
No description available.
113

Journalistic paradigms on social protest: the case of the Jubilee School affair in Hong Kong.

January 1981 (has links)
by Joseph Man Chan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 147-153.
114

西西一九六零年代影話寫作研究. / Study on cinematic writings of Xi Xi in the 1960s / CUHK electronic theses & dissertations collection / Xi Xi 1960 nian dai ying hua xie zuo yan jiu.

January 2013 (has links)
趙曉彤. / "2013年8月". / "2013 nian 8 yue". / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 171-178). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in Chinese and English. / Zhao Xiaotong.
115

自由的書寫: 一個城市作家 : 西西. / Freedom of writing: Xi Xi as an urban writer / 一個城市作家: 西西 / CUHK electronic theses & dissertations collection / Zi you de shu xie: yi ge cheng shi zuo jia : Xi Xi. / Yi ge cheng shi zuo jia: Xi Xi

January 2013 (has links)
「自由」在本論文中,可以理解為實體、抽象、比喻意義上的「通道」。我認為那些最初大概源於城市經驗的關於通道的想像,既是西西致力書寫的對象,也是她小說美學的理想。以本雅明的《拱廊街計劃》(Das Passagen-Werk),以及狄雪圖的步行者美學作為理解「通道」的起點。人群、商品、貨幣、資訊等的流動變易可說是它最重要的特質,從維希留速度學的角度看來,它的極致則是「消失」的空間。 / 我使用通道一詞,不僅指向西西小說中現實的城市空間和它的實踐者(通過對庶民生活細緻而富有詩意的描寫,在理論家們看來,日漸抽象無法把握的城市文化,在西西小說裡卻呈現出它最具質感而活潑的部分),同時也是西西多年來在寫作這門技藝漸漸透現的美學特徵,以及價值理想。這意味著西西以多重視點、對話、拼貼、互文,混合媒介等等技法來創造文本的開放視野,以及流動狀態,但這些明顯具有「後現代」特徵的形式並不指向意義消解的世界,它們的遊戲性充滿了對世界的深情關注。因此,西西的「通道」既有著資本主義城市開放流動的特徵,但同時也是對它那種無情個性的抵抗。流動意味著的不是消失,而是溝通與對話,以致於透現出一種生命意識:宇宙萬物可以彼此轉化流動。 / In this dissertation, “freedom can be understood as “passages in their literal, abstract and figurative senses. I consider the concept of “passages as inspired initially by urban experience, and as the theme and aesthetic ideal of Xi Xi’s fiction. Using Walter Benjamin’s The Arcades Project (Das Passagen-Werk) and Michel de Certeau’s notion of “street walkers as a starting point, the most important characteristic of “passages can be seen as their fluid, transient nature in terms of people, commercial goods, currency, information, etc.; and from the perspective of Paul Virilio’s dromology, they can be spaces of “disappearance in their most extreme form. / I use the term “passages, not only to refer to urban space and its practitioners in Xi Xi’s novels (through the poetic and meticulous descriptions of ordinary people’s daily lives, which demonstrates how Xi Xi’s work represents the most concrete and liveliest parts of urban culture--in spite of theorists’ notion of the city as an increasingly abstract space), but also to reflect the aesthetic features, ideals, and values developed over the years in Xi Xi’s writing. Using the techniques of different points of view, dialogue, collage, intertextuality, mixed media, etc., Xi Xi’s fiction enables formal fluidity and openness. But the obvious “postmodern characteristics of these formal experiments do not aim at the elimination of meaning. Rather, the playful gestures in these works are full of affectionate attention toward the world. Xi Xi’s work, therefore, adapts the fluidity of “passages in a capitalist city, but at the same time, resists its ruthless nature. “Passages in her work do not imply disappearance, but communication and dialogue. They also exhibit a vision of life: all things in the fluid universe can transform into each other. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / 謝曉虹. / "2013年7月". / "2013 nian 7 yue". / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 73-75). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in Chinese and English. / Xie Xiaohong. / Chapter 引言 --- 關於通道的美學 --- p.(頁1) / Chapter 第一章 --- 穿牆人 / Chapter 第一節 --- 牆 --- p.(頁9) / Chapter 第二節 --- 名字 --- p.(頁11) / Chapter 第三節 --- 離地 --- p.(頁14) / Chapter 第四節 --- 故事的形狀 --- p.(頁17) / Chapter 第二章 --- 通道 / Chapter 第一節 --- 通道 --- p.(頁22) / Chapter 第二節 --- 陌生人 --- p.(頁28) / Chapter 第三節 --- 公共人 --- p.(頁32) / Chapter 第三章 --- 眼睛 / Chapter 第一節 --- 眼睛 --- p.(頁35) / Chapter 第二節 --- 沉思者 --- p.(頁38) / Chapter 第三節 --- 店玻璃 --- p.(頁42) / Chapter 第四章 --- 軟世界 / Chapter 第一節 --- 五十七個電視 --- p.(頁47) / Chapter 第二節 --- 縫接 --- p.(頁49) / Chapter 第三節 --- 肉體與石頭 --- p.(頁52) / Chapter 第四節 --- 軟世界 --- p.(頁55) / Chapter 第五章 --- 造房子 / Chapter 第一節 --- 立體房子 --- p.(頁59) / Chapter 第二節 --- 無數度 --- p.(頁62) / Chapter 第三節 --- 房子的自由 --- p.(頁67) / 引用書目 --- p.(頁73)
116

Archetype and allegory in "Journey to the West"

Zhang, Kai 04 November 2009 (has links)
The Journey to the West (西游记) is one of the masterworks of classic Chinese fiction. It was written by Wu Cheng‘en (吴承恩) in the 16th century CE. Many of the scholars, both Chinese and Western, who have studied the narrative of this Ming era (1368-1644) novel, have considered it to be an epic of myth and fantasy, heavily laden with allegorical meaning. Most scholars have chosen to interpret the novel by means of an encompassing framework of meaning rooted in the convergence of the teachings of Buddhism, Taoism and Confucianism. I propose to look at the Journey’s narrative structure as a heroic adventure or monomyth of the kind proposed by Joseph Campbell, following the insights of Carl Jung on the nature of the collective unconscious. To analyze the component parts of the quest story that forms the bulk of the novel‘s narrative, I shall turn to Vladimir Propp‘s categorization of the functioning of elements of plot and character in his morphology of folktales. I shall also argue that the Journey is not an allegory that serves the beliefs and practices of a number of religions and philosophies, but a specifically Buddhist allegory. The Journey is seen as intentionally composed of symbols, images, and codes that function to project a heroic adventure with a complex pattern of meaning, primarily representing the eternal human struggle for identity and a fully realized existence, that are Buddhist in nature.
117

Efeito da adi??o de grafite expandido por microondas nas propriedades t?rmicas, el?tricas e mec?nicas de nanocomp?sitos de matriz ep?xi

Marinho, Ant?nio Calmon de Ara?jo 26 February 2014 (has links)
Made available in DSpace on 2014-12-17T14:07:16Z (GMT). No. of bitstreams: 1 AntonioCAM_DISSERT.pdf: 2526278 bytes, checksum: 858d8dc4858eb48a9d6ce6faab8763d4 (MD5) Previous issue date: 2014-02-26 / Universidade Federal do Rio Grande do Norte / Epoxy based nanocomposites with 1 wt % and 3 wt % of nanographite were processed by high shear mixing. The nanographite was obtained by chemical (acid intercalation), thermal (microwave expansion) and mechanical (ultrasonic exfoliation) treatments. The mechanical, electrical and thermal behavior of the nanocomposites was determined and evaluated as a function of the percentage of reinforcement. According to the experimental results, the electrical conductivity of epoxy was not altered by the addition of nanographite in the contents evaluated. However, based on the mechanical tests, nanocomposites with addition of 1 wt.% and 3 wt.% of nanographite showed increase in tensile strength of 16,62 % and 3,20 %, respectively, compared to the neat polymer. The smaller increase in mechanical strength of the nanocomposite with 3 wt.% of nanographite was related to the formation of agglomerates. The addition of 1 wt.% and 3 wt.% of nanographite also resulted in a decrease of 6,25 % and 17,60 %, respectively, in the relative density of the material. Thus, the specific strength of the nanocomposites was approximately 33,33 % greater when compared to the neat polymer. The addition of 1 wt.% and 3 wt.% of nanographite in the material increased the mean values of thermal conductivity in 28,33 % and 132,62 %, respectively, combined with a reduction of 26,11 % and 49,80 % in volumetric thermal capacity, respectively. In summary, it has been determined that an addition of nanographite of the order of 1 wt.% and 3 wt.% produced notable elevations in specific strength and thermal conductivity of epoxy / Nanocomp?sitos a base de resina ep?xi e nanografite foram processados por mistura de alto cisalhamento, com concentra??es de 1 % e 3 % p/p de refor?o. O nanografite foi obtido atrav?s de tratamentos: qu?mico (intercala??o ?cida), t?rmico (expans?o por microondas) e mec?nico (esfolia??o por ultrassom). Os comportamentos mec?nico, el?trico e t?rmico dos materiais obtidos foram analisados em fun??o da porcentagem de refor?o. De acordo com os resultados obtidos, n?o foram verificadas altera??es na condutividade el?trica do ep?xi com a adi??o de nanografite, nos percentuais estudados. Entretanto, com base nos ensaios mec?nicos observou-se que os nanocomp?sitos com adi??o de 1 % p/p e 3 % p/p de grafite expandido apresentaram aumento na resist?ncia ? tra??o de 16,62 % e 3,20 % respectivamente, em rela??o ao pol?mero puro. O menor aumento de resist?ncia mec?nica para os nanocomp?sitos com 3 % p/p de nanografite foi relacionado com a forma??o de aglomerados. A adi??o de 1 % p/p e 3% p/p de nanografite tamb?m resultou em uma diminui??o de 6,25 % e 17,60 %, respectivamente, na densidade relativa do pol?mero. Portanto, a eleva??o da resist?ncia espec?fica dos nanocomp?sitos foi de aproximadamente 33,33% para os dois nanocomp?sitos, em rela??o ao pol?mero puro. A adi??o de 1 % p/p e 3 % p/p de nanografite no material aumentou os valores m?dios de condutividade t?rmica em 28,33 % e 132,62 %, respectivamente, combinado com uma redu??o de 26,11 % e 49,80 %, respectivamente, na capacidade t?rmica volum?trica. Em resumo, verificou-se que uma adi??o de nanografite da ordem de 1 % e 3 % p/p produziram eleva??es not?veis na resist?ncia mec?nica espec?fica e condutividade t?rmica do ep?xi
118

De Paris à Rome : Jean-Baptiste Théodon (1645-1713) et la sculpture française après Bernin / From Paris to Rome : Jean-Baptiste Théodon (1645-1713) and French Sculpture after Bernini

Adamczak, Alicia 05 December 2009 (has links)
Sculpteur du règne de Louis XIV, Jean-Baptiste Théodon (1645-1713) se rattache à l’école française autant qu’à l’école romaine de sculpture. Formé auprès de Charles Le Brun à la Manufacture royale des Gobelins, il y rencontre Jean-Baptiste Colbert qui devient son premier mécène. Protégé par ce dernier qui l’envoie en Italie, Théodon rejoint en 1677 l’Académie de France à Rome où il sculpte pour Louis XIV et le château de Versailles. Parallèlement il prend part à la vie académique romaine. Membre actif de l’Accademia di San Luca et de la congrégation des Virtuosi al Pantheon, Théodon devient l’un des sculpteurs les plus recherchés de la Rome de la fin du Seicento, sollicité par les papes Innocent XII et Clément XI à Saint-Pierre de Rome et au Latran, et par les congrégations et les ordres religieux au Gesù et au Monte di Pietà. Appelé par Louis XIV, il revient à Paris en 1705 et contribue, durant ses dernières années, à la décoration des Maison royales de Marly et de Meudon. Abordant avec brio l’allégorie et la sculpture animalière pour Colbert, la mythologie et le genre historique pour Louis XIV, la sculpture funéraire et l’art du portrait pour Christine de Suède, le sculpteur s’illustre avant tout dans l’art religieux. Brillante personnalité artistique du XVIIe siècle, Théodon méritait une étude. Nous avons considéré sa vie et sa carrière, analysé sa manière et établi le corpus exhaustif de son œuvre. / Jean-Baptiste Théodon (1645-1713) was a French sculptor of the reign of Louis XIV who belonged both to the French and Italian schools of sculpture of the Seventeenth-Century. In the 1670’s during his training at the ‘Manufacture des Gobelins’ he worked under the supervision of Charles Le Brun and met the minister Jean-Baptiste Colbert. In 1677 he joined the French Academy in Rome where he carved garden sculptures for royal estates and for his protector Colbert. Early in his Roman carrier he was made member of the Academy of St Luke and member of the Congregazione dei Virtuosi al Pantheon where he met Bernini, the architect Carlo Fontana and the painter Carlo Maratta. Appreciated by the Pope Innocent XII he obtained several commissions at Saint-Peter’s (Baptismal chapel, Monument to Christine of Sweden) and at the same time he worked for the Jesuits at the Sant’Ignazio chapel at the Gesù. As one of the most significant sculptors of the end of the Roman Seicento he dedicated his last years in Rome to the pope Clement XI and the papal basilica before his return to Paris in 1705 where he worked for the Sun King and the ‘Maisons’ of Meudon and Marly. With the same maestria Jean-Baptiste Théodon carved allegories for Colbert, mythological and historical figures for Louis XIV, funeral sculptures and portrait for Christine of Sweden as well as works of art for Roman churches. The Ph.D. dissertation consists of a study of the career of the sculptor with an analysis of his artistic manner and its evolution from Paris to Rome. In addition the thesis includes the complete ‘catalogue raisonné’ of his works, sculptures and drawings.
119

Morfologia e propriedades mec?nicas da fibra de sisal unidirecional e em sobreposi??o de comp?sito com resina ep?xi / Morphology and mechanical properties of the fiber and overlapping unidirectional composite with epoxy resin

Holanda, Elis?ngela Bezerra das Neves 14 January 2013 (has links)
Made available in DSpace on 2014-12-17T14:58:21Z (GMT). No. of bitstreams: 1 ElisangelaBNH_DISSERT.pdf: 5500408 bytes, checksum: 312e914c2b5560a38c07ef6f6b3c70be (MD5) Previous issue date: 2013-01-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The composites manufactured with long fibres aligned in a single direction, and overlay has been shown to have better performance than the short fibers randomly distributed. In particular, the lignocellulosic fibers extracted from the sisal leaves, used in conjunction with the epoxy resin has attracted the attention of many researchers because the final properties of the system formed. In this work composites based on epoxy resin reinforced with sisal fibers were manufactured. The sisal fibres were treated with an alkaline solution of 0.06 mol/l NaOH. The treated, and untreated fibres were subjected to tension x extension tests. The composites were manufactured in the "Lossy" mold with the specifications of the samples to be produced (300x20x4 mm). The tension tests were carried out in accordance with the ASTM standards 3039 (for the composite aligned in a single direction) and ASTM D5573 (for composites in overlay), three point bending tests were performed according to ASTM D790. Analyzing the results of the tests of tension and three point bending tests, it was observed that the composites with the configuration of overlapping had the better elastic module in both tests. As to the maximum resistance to tension, the best result was the composites aligned in a single direction. Tests of absorption of water and micrographs are in progress / Os comp?sitos fabricados com fibras longas alinhadas unidirecionalmente e em sobreposi??o tem demonstrado que possuem melhor desempenho do que as fibras cortadas aleatoriamente distribu?das. Em especial, as fibras lignocelul?sicas extra?das do sisal, utilizadas em conjunto com a resina ep?xi tem atra?do a aten??o de muitos pesquisadores devido ?s propriedades finais do sistema formado. No presente trabalho foram fabricados comp?sitos ? base de resina ep?xi refor?ado com fibras de sisal. As fibras de sisal foram submetidas ao tratamento alcalino com NaOH a 0,06 mol/l, em seguida submetidas ao ensaio de tra??o na fibra tratada e n?o tratada. Os comp?sitos foram fabricados no molde denominado de Lossy (molde com perdas) usinado de acordo com as especifica??es das amostras a serem produzidas (300x20x4 mm). Os ensaios de tra??o foram realizados de acordo com as normas ASTM 3039 (Para os comp?sitos alinhados unidirecionalmente) e ASTM D5573 (Para os comp?sitos em sobreposi??o), os ensaios de flex?o em tr?s pontos foram realizados de acordo com as normas ASTM D 790. Analisando os resultados dos ensaios de tra??o e flex?o em tr?s pontos, foram observados que os comp?sitos com a configura??o de sobreposi??o teve melhor m?dulo de elasticidade em ambos os ensaios. Quanto a resist?ncia m?xima a tra??o o melhor resultado foi do comp?sito alinhado unidirecionalmente. No ensaio de absor??o de ?gua foi observado que os comp?sitos possuem um n?vel muito baixo de absor??o e o comp?sito alinhado unidirecionalmente obteve percentual de satura??o de 1,97 %. Nas micrografias, se observa as regi?es de ruptura/trincas do comp?sito e seu comportamento (fibra/matriz)
120

Adi??o de poli(etileno-co-?cido-metacr?lico) (EMAA) como agente de auto-reparo em comp?sitos carbono-ep?xi

Nascimento, Allana Azevedo do 16 October 2017 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2018-02-15T11:17:49Z No. of bitstreams: 1 AllanaAzevedoDoNascimento_DISSERT.pdf: 3970437 bytes, checksum: 117bfe2f45af82aa1ce79c2ec7c811e1 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2018-02-16T11:03:56Z (GMT) No. of bitstreams: 1 AllanaAzevedoDoNascimento_DISSERT.pdf: 3970437 bytes, checksum: 117bfe2f45af82aa1ce79c2ec7c811e1 (MD5) / Made available in DSpace on 2018-02-16T11:03:56Z (GMT). No. of bitstreams: 1 AllanaAzevedoDoNascimento_DISSERT.pdf: 3970437 bytes, checksum: 117bfe2f45af82aa1ce79c2ec7c811e1 (MD5) Previous issue date: 2017-10-16 / As t?cnicas de auto-reparo em resinas ep?xi v?m sendo desenvolvidas buscando aumentar a vida ?til e reduzir os custos associados ? manuten??o desses materiais durante o servi?o. A adi??o de termopl?sticos ? matriz termofixa produzindo resinas repar?veis aparece como t?cnica de reparo promissora. Neste trabalho, o termopl?stico poli (etileno-co-?cido-metacr?lico) (EMAA) foi adicionado no plano m?dio de laminados comp?sitos carbono-ep?xi para fabrica??o de um sistema de reparo. Foram fabricadas placas com 5%, 10% e 15% de EMAA em massa de resina do prepreg. Ensaios de resist?ncia ao cisalhamento interlaminar (ILSS), an?lise din?mico mec?nica (DMA), espectroscopia de infravermelho por transformada de Fourier (FTIR), microscopia eletr?nica de varredura (MEV) e microscopia eletr?nica de varredura com fonte de emiss?o de campo (MEV-FEG) foram conduzidos para avaliar o efeito da adi??o desse termopl?stico ao comp?sito e seu comportamento antes e ap?s o reparo. As amostras reparadas n?o apresentaram aumento na resist?ncia ao cisalhamento interlaminar (ILSS) ap?s o reparo. Entretanto, para maiores porcentagens de EMAA, houve redu??o dessa propriedade, al?m de redu??o de m?dulo de elasticidade e da temperatura de transi??o v?trea (Tg), em rela??o aos valores apresentados pelo comp?sito puro. Imagens de MEV confirmaram a forte ades?o entre o EMAA e a resina ep?xi, formando uma camada adesiva que impediu a forma??o de delamina??es no plano m?dio do laminado. / Self-healing techniques in epoxy resins have been developed to improve the durability and reduce costs associated with repairs of these materials during service. The addition of thermoplastics into the thermoset matrix producing mendable resins appears as a promising self-healing technique. In this study, poly(ethylene-co-methacrylic acid) (EMAA) was added in the mid-plane of carbon fiber-epoxy composites laminates to produce a self-healing system. Plates were manufactured with addition of 5%, 10% and 15% of EMAA as related to the resin weight of prepreg. Interlaminar shear strength test (ILSS), dynamic mechanical analysis (DMA), Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and field-emission gun scanning electron microcopy (FEG-SEM) were employed in order to evaluate the effect of the addition of the thermoplastic to the composite and its behavior before and after a healing cycle. The healed samples did not show an increase in interlaminar shear strength (ILSS) after healing. However, for higher percentages of EMAA there was a reduction of this property, besides a reduction of Young?s modulus and glass transition temperature (Tg), in relation to the values presented by the unmodified composite. SEM images confirmed the strong adhesion between EMAA and epoxy resin, which produced an adhesive layer that prevented delamination in the mid-plane of the laminate.

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