Academic literature on the topic 'Pushto Poets'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Pushto Poets.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Journal articles on the topic "Pushto Poets"
1
Hartman, Megan E. "The Form and Style of Gnomic Hypermetrics." Studia Metrica et Poetica 1, no. 1 (April 22, 2014): 68–99. http://dx.doi.org/10.12697/smp.2013.1.1.05.
Full textAbstract:
Gnomic poems have often been noted for their unusual metrical style. One aspect of their style that stands out is the hypermetric usage, both because these poems contain a notably high incidence of hypermetric verses and because the verses are frequently categorized as irregular. This paper analyses hypermetric composition in Maxims I, Maxims II, and Solomon and Saturn in detail to illustrate the major stylistic features of gnomic composition. It demonstrates that, contrary to the conclusions of some previous scholars, the hypermetric verses basically follow the form for hypermetric composition that can be found in most conservative poems, but with the inherent flexibility of hypermetric metre pushed to a greater extent than in most narrative poems, making for lines that are longer, heavier, and more complex. This alternate style highlights the importance of each individual aphorism and characterizes the solemnity of the poems as a whole. By composing their poems in accordance with the trends of this specialized style, poets may have been marking their composition as separate from narrative poems and encouraging their audience to consider each individual poem in the larger context of Old English wisdom poetry.
2
Aprilliani Wijono, Yunanda. "Decline in Nature: an Intertextual Study." Udayana Journal of Social Sciences and Humanities (UJoSSH) 3, no. 2 (September 30, 2019): 70. http://dx.doi.org/10.24843/ujossh.2019.v03.i02.p02.
Full textAbstract:
Human and nature had been living side by side and help each other since ancient times. However, the current condition of nature had pushed other humans to be aware that this ‘side by side living’ had not only been advantageous but also exploited. This is recorded by humans through literacy; starting from poems. However, these records did not only contain history but also expressions of poets and authors alike; their perspective of nature they see in their existence and or, perhaps, their hope or view of the future of nature. To find whether a work conveys life through nature or whether it conveys nature from different aspects of life, a study is needed. This writing aims to interpret the nature represented in William Blake’s The Tyger and Gordon J. L. Ramel’s Tiger, Tiger Revisited. The method used is library research and the approach used in intertextuality by focusing on the human-wildlife relationship over the years both poems were written. The results show that these poems are similar in their nature as poems. However, their idea of nature contradicts each other in the use of the figure of speech. Nature had changed drastically over the years these poems are made, and those changes are conveyed within the two poems.
3
Abraham, Obakachi A. "A Comparative Study of Environmental Struggles in the Poetry of Tanure Ojaide and Marilyn Dumont of First Nations (Canada)." International Journal of Literature, Language and Linguistics 6, no. 1 (January 11, 2023): 1–14. http://dx.doi.org/10.52589/ijlll-dm16c8xp.
Full textAbstract:
Earlier studies on the Niger Delta poetry of Nigeria and First Nations poetry of Canada have focused primarily on the environmental and minority concerns in the individual literature of these two regions. The environmental concerns in these two literary traditions are a result of the minority status of the regions with hegemonies depriving the indigenous people of control in the ways their landscapes and waterscapes are engaged. This present study takes these issues to a comparative level, investigating how the two marginal groups are reacting to the hegemonies that pushed them to the peripheries and the aesthetics the selected poets employ to combat local and global environmental changes in their collections. Tanure Ojaide’s Niger Delta Blues and Other Poems, and Dumont Marilyn’s The Pemmican Eaters are comparatively explored with the focus of exposing the similarities and differences in the portraitures of their environments. This study finds that the selected poets from both regions depict the primordial symbiotic relationship that existed between humans and non-humans in their environments, especially prior to the commencement of mineral resources exploitation in their regions. Poems from both regions compare the harmonious past with the disharmony of the present to raise global awareness of the problems caused by capitalist agents in the exploitation of the environment. Similarly, oral traditions are depicted as viable aesthetics which promote the harmonious human-environment relationship. The selected collections of poetry have political undertones and represent the people’s collective aspirations, it is against this that they recreate the myths around their activists and heroes to document the history and raise environmental consciousness among the people. The poets of the two literary traditions compared, however, differ in the following areas: the poets of First Nations are more impressionistic in depicting environmental struggles while Niger Delta poets rely on metaphors and images to portray their environmental struggles. The study concludes that the environmental and minority struggles portrayed in the selected collections show the pursuit of environmental justice for their marginalised regions, and by extension, it is a contribution to the global environmental discourse.
4
Chen, Juanyu. "The Romantic Style of P. B. Shelley s Poetry." Communications in Humanities Research 20, no. 1 (December 7, 2023): 19–24. http://dx.doi.org/10.54254/2753-7064/20/20231269.
Full textAbstract:
Shelley s poetry is rich and varied, harmonious in tone, delicate in feeling and expansive in artistic conception, which pushed the British romantic poetry to the peak. Shelley had a very high talent, received a good education since childhood, coupled with diligent thinking, and has twists and turns of life experience, so his works all reflect the pursuit of the truth of the strong philosophical mood. This article mainly focuses on two of Shelley s poems to analyze the romantic style of his poems from the image and theme. Shelley, as a political poet and lyric poet, expressed his poetic aesthetics very clearly. He endowed poets with a lofty mission, believing that they shoulder the dual mission of social revolution and artistic innovation. Of course, Shelley believes that this dual mission is realized in the poet s creative artistic imagination. Therefore, in Shelley s view, the real imaginary expression of poetry should have a spiritual inspiration and aesthetic influence. It can be said that Shelley s poetry aesthetics not only clearly reflects the characteristics of his changing era, but also illustrates his romantic aesthetic stance. Shelley s aesthetic thoughts of poetry are enlightening for people to better appreciate and understand his poems.
5
Rezvani, Saeid. "Outdated Humanism and Literary Authority as Threats to the Popularity of Ahmad Shāmlu’s Poetry." Advances in Language and Literary Studies 10, no. 1 (February 28, 2019): 117. http://dx.doi.org/10.7575/aiac.alls.v.10n.1p.117.
Full textAbstract:
Shāmlu belongs to the few poets of the modern Persian poetry, who can be called neoclassical, namely, those whose work has a distinctive character and who are influential in the history of modern Persian literature. These special characteristics of Shāmlu’s poetic features together with his socio-cultural and political vision as manifested in his poems had excessively allowed for his oeuvre to be popularized, forming a large crowd of admirers who even tried to mythologize his character and art. Shāmlu’s enthusiastic admirers, moreover, insist that his poetry is everlasting and even immortal. This article claims that critics should not function as judges of history, declaring a contemporary work of art as an immortal artefact. To this light, the article will argue that Shamlu’s innovation in poetry is not just linguistic, but rather an element that signifies his intellectual superiority. Moreover, the article examines two characteristics of Shāmlu’s poetry, which could probably endanger the popularity of his poems with future generations. It, therefore, first explores the authoritative position of the poet vis-à-vis his audience; and then examines the special relationship of humans with nature.INTRODUCTIONIn the modern Persian poetry, Ahmad Shāmlu is best seen as a neo-classist whose poetry bears a distinctive structural quality, allowing for the work and at once the poet to emerge as historico-literary markers. The elements that had pushed Shāmlu’s poetry to such literary significance are as follows:- Shāmlu is one of the few poets with a distinctive language of his own. While some scholars find Nimā Yushij as the progenitor of modern Persian poetry, Shāmlu belongs to a minor crowd with a rather personal and particular language and lingual authority. Shāmlu’s take on language, the sort which is regarded as a combination of the 4th and 5th century prose (Barāhani, Qāleb-e sheʻr-e Shāmlu, p. 895) with contemporary features and even slangs and colloquial discourse (Rezvani, pp. 179, 185-187), appears as one of the accepted poetic languages of the modern Persian poetry. Considering the notable number of current modern Persian poets who had borrowed from “linguistically authoritative” poets, one can understand Shāmlu’s
6
Al-Lami, Sawsan Azeez Khlaif. "The concept of Modesty in the Poetry of Behçet Necatigil." Al-Adab Journal 2, no. 140 (March 15, 2022): 137–50. http://dx.doi.org/10.31973/aj.v2i140.3625.
Full textAbstract:
Behçet Necatigil is considered one of the important Turkish authors in the 20th century. He was born in FATİH district in Istanbul in 1916 and died on 13 of December 1979 in Istanbul. The poet Necati started writing while he was very young. He had several important works in his short life that lasted only 63 years. Although he was creative in several and different works in literary types such as Drama, Translation, the art of conversing, and radio drama, the poet Behçet Necatigil who was known by his poetic identity, is considered one of the most important poets in Turkish literature and the successful one among them.
The concept of modesty is a synonym to simplicity which includes several meanings such as not to be snobbish, or dictator which is a humane phenomenon in its concept. This concept of modesty is considered one of the positive conducts and one of the most important concepts that society respects and adopts it and eager to have it. In general, everyone aims at being a simple, moderate and not a snobbish person. Regardless of the spiritual and materialistic status of any person, this means that he adopted a lifestyle that is ordinary and simple. The poet Behçet Necatigil is one of the poets who adopted this situation all over their lives and was eager to be a moderate person. Thus, we see this concept clear in his poems.
This is the reason that pushes us to write a research paper specifically on the poet Behçet Necatigil. We see that he is a person full of modesty and simplicity. He has largely and successfully used in his poems the concept of modesty as well as its derivatives. Our research paper will focus on this concept, and we will introduce a short summary about the life of the poet and his literary personality as well as his works. Then we sill study the concept of modesty in details. After that, we will expand our research paper to talk about how this concept has been used in the poems written by Behçet Necatigil.
7
Raufi, Shah Rukh, and Abdul Rab Monib. "خليـلي وشـوقي في قصيدتيهما «مجسمه باميان» و «أبي الهول»؛ دراسة مقارنة." ALLAIS Journal of Arabic Language and Literature 2, no. 2 (December 31, 2023): 1–26. http://dx.doi.org/10.22515/allais.v2i2.8021.
Full textAbstract:
This research aims to review two poems by two of the stalwarts of Arabic and Persian poetry in the modern era, and the extent of influence and effect through comparative literature. It follows the applied analytical approach in light of the cultural and historical relations between the two literatures. Accordingly, he studies each poem, points out the similarities and differences between the two poems, and reveals some of the artistic aesthetics and creativity that characterize each poem. It became clear through the presentation of the two poems that the two poets expressed the past days and the ease and luxury that surrounded them, and the roughness and poverty that accompanied them. Then Shawqi sees the secret of the farmer in movement, moving forward, and leaning on oneself. The people of the country only serve their own people. As for Al-Khalili, he continued his complaints about the people of his time. Humanity has perverted and the mind is shackled in the era of scientific progress. It has become clear that Khalili, despite his knowledge of the Arabic language, and Shawqi being ahead of him in time, may have read Shawqi’s poem or been inspired by its subject, but he did not notice that he took one of the meanings. In addition to this, his treatment is radically different from him. When Shawqi pushes his statue to move, My boyfriend instructs him to hide from sight because the controlling madman might harm him and humanity has gone awry and does not redress injustices or shelter him; The poem is the tragedy of a people abandoned by humanity due to a brutal occupation.
8
Willett, Mischa. "‘Fading Crimean Flowers’: Spasmodic Sonnets on the War." Victoriographies 8, no. 2 (July 2018): 135–50. http://dx.doi.org/10.3366/vic.2018.0302.
Full textAbstract:
In their refusal to aestheticise Crimean warfare, as most of their fellow poets and newspapermen had done, Sydney Dobell and Alexander Smith, in the co-authored Sonnets on the War (1855) present a harrowing picture of the conflict from myriad viewpoints, all of which deny the patriotism and hawkishness implicit in glamorising armed conflict. This poly-vocalic collection pushes more boundaries than has previously been noticed. The choice of form, itself a commentary – this is not a war fit for epic – the emphasis on women's roles, and the anonymous and ventriloquised voicing announce departures from conventions of martial verse, and also from what we have heretofore understood about these poets’ careers.
9
Parmar, Amisha. "Representation of cities as spaces through symbolist imagery in T.S. Eliot’s The Wasteland and Arun Kolatkar’s Kala Ghoda." International Journal of English Literature and Social Sciences 8, no. 5 (2023): 093–97. http://dx.doi.org/10.22161/ijels.85.16.
Full textAbstract:
In twentieth-century's poetry, the city has become an important and complex theme because when writing about cities, poets tend to re-formulate and re-define their relation with literary and cultural traditions. The city poses a particular challenge for the modern poets because of their commitment to social and cultural traditions they feel that their role has been fused to simply responding to the social, moral, cultural and psychological transformations that the city symbolizes. Is it right to read a poet, or poetry, as an extension of a place? The answer is may or may not be. The question is to answer the unique narrative description of Bombay in Arun Kolatkar’s Kala Ghoda and the city of London in T.S. Eliot’s The Wasteland that defines the city using imagery and symbolism in the best manner. Walking through Bombay and reading Kala Ghoda Poems recreates a city that is constantly shifting and dancing around, full of noises and colours, all the while exposing those lives that are pushed out of an expanding concrete jungle, hidden under bright lights and tall towers—the triumphs of development. Eliot utilises the ‘unreal city’ London as the main setting for The Wasteland and the city comes to embody the title of the poem that id portrayed as ugly, cruel and grey, lacking any real human warmth or meaningful connections. The study will be centred on a reading and analysis of deconstructive poetry to show how postmodernism is hinted at while also demonstrating continuous sociocultural and socioreligious activities through the use of symbolism and imagery. The study will continue with chapters broken down into many aspects, including a comparative analysis of Eliot and Kolatkar's poetry, studying the issue of experimentalism and symbolism as well as imagery employed in Kolatkar's Kala Ghoda and Eliot's Wasteland. The subjectivities and experimentation in Indian English poetry and Western poetry can be understood and explored through a comparison of Arun Kolatkar and T.S. Eliot.
10
Mozumder, Subrata Chandra. "Love, Sex and the Body in The Bell Jar and My Story:." Crossings: A Journal of English Studies 8 (August 1, 2017): 136–43. http://dx.doi.org/10.59817/cjes.v8i.137.
Full textAbstract:
This paper seeks to explore the themes of love, sex, and the body in The Bell Jar and My Story, two much-read autobiographical texts by Sylvia Plath and Kamala Das respectively, which reveal the writers’ feminist “self.” These books were published in the mid-twentieth century when women started fighting for their individual freedom by interrogating patriarchal hegemony responsible for delimiting women’s familial, social, economic, educational, industrial, and political rights. Both Plath and Das possess unconventional approaches towards love, sex, and the body. Their texts come out as threats to the patriarchal practice which pushes women to “stay at home, cook meals, clean house and bear children” (Lamb 1). For these poets, the woman’s body, which patriarchy mostly considers an object of sexual pleasure, is a significant tool for transgressing the dictums of patriarchy. The present study, therefore, aims at showing the themes of love, sex, and the body in the above mentioned texts as a means for the poets to interrogate patriarchal restraints and to create a new identity with self-esteem and self-worth. In this way, they refuse to accept the hegemonic role of oppression and assert their gender identity.
Dissertations / Theses on the topic "Pushto Poets"
1
Vasconcelos, Rafaela Andrade de [UNESP]. "Avaliação da influência de materiais obturadores endodônticos sobre a resistência de união adesiva de pinos de fibra de vidro cimentados." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138113.
Full textAbstract:
Submitted by RAFAELA ANDRADE DE VASCONCELOS null (rafaela-vasconcelos@hotmail.com) on 2016-04-27T21:04:50Z
No. of bitstreams: 1
vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5)Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-27T21:10:57Z (GMT) No. of bitstreams: 1 vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5)
Made available in DSpace on 2016-04-27T21:10:57Z (GMT). No. of bitstreams: 1 vasconcelos_ra_dr_sjc.pdf: 1223725 bytes, checksum: f212f1adab3c030b4b7089bfeacaf463 (MD5) Previous issue date: 2016-03-18
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O propósito deste estudo foi avaliar, in vitro, a influência de remanescente de materiais obturadores endodônticos, após desobturação e preparo para pino, sobre a resistência de união adesiva de pinos de fibra de vidro cimentados. Foram utilizados 60 dentes humanos unirradiculados sem coroa. As raízes foram preparadas pela técnica coroa-ápice com sistema Reciproc. Para obturação, as raízes foram divididas em grupos (n = 10) de acordo com o cimento endodôntico utilizado: SO= sem obturação; GP=guta percha sem cimento; AHP= guta-percha + AHPlus; SLP= guta-percha + Sealapex; IRT= guta-percha + iRoot SP; e ERZ= guta-percha + EndoRez. As raízes foram obturadas pela técnica do cone único. A cimentação dos pinos de fibra de vidro Rebilda n.12 foi realizada com sistema adesivo futurabond DC e cimento Rebilda DC em 10 mm do comprimento da raiz. Após esse período, as raízes foram seccionadas obtendo-se discos de 2 mm de espessura em cada terço da raiz (3 discos por raiz) que foram submetidos ao teste de push out, análise por meio de uma lupa estereoscópica (40x) para identificação através de scores da presença de remanescente de material obturador na luz do canal e avaliação por espectroscopia de energia dispersiva (EDS) para identificação de remanescente de componentes químicos do cimento endodôntico presentes nos túbulos dentinários. Os dados obtidos foram analisados estatisticamente pelos testes de Kruskal Wallis, Qui Quadrado e teste de Anova e Tukey, todos com nível de significância de 5%. Não houve diferença estatística para a resistência adesiva entre os cimentos na região cervical (p = 0,49), media (p = 0,28) e apical (p = 0,09). Os grupos SLP e ERZ apresentaram menos remanescente de material obturador nas regiões cervical (p = 0,045) e apical (p = 0,006). Significantes diferenças de remanescentes de componentes químicos foram observadas na região apical dos grupos AHP, IRT e SLP. Conclui-se que os materiais endodônticos não influenciaram na resistência de união adesiva de pinos de fibra de vidro.
The purpose of this study was to evaluate the influence of remnants endodontic filling material in root canal on the bond strength of fiberglass posts cemented. Sixty single-rooted human teeth were used.Crowns were removed. The roots were prepared by crown-down technique with Reciproc system. For fillings, the roots were divided (n = 10) according to the sealer used: SO- without fillings; GP-gutta-percha without sealer; AHP- gutta-percha + AHPlus; SLP- gutta-percha + Sealapex; IRT-gutta-percha + iRoot SP; ERZ-and gutta-percha + EndoRez. Single cone obturation technique was used. After root canal fillings, the teeth were kept in an oven 37 0C for 7 days. Cementing fiberglass posts Rebilda n.12 was performed with fiber adhesive system Futurabond DC and cement Rebilda DC in 10 mm of root length, getting stored in an oven at 37 0C for 48 h. After this period, roots were sectioned obtaining 1 disc of 2 mm thickness in each third of the root (3 discs per root), this discs were underwent to push out test, analyzed by means of a stereomicroscope (40x) to identify the presence of remnants of filling material in the lumen of the canal, and then evaluated by energy dispersive spectroscopy (EDS) for identification of chemical components remnants sealer present in the dentinal tubules. Datas were analyzed with Kruskal-Wallis test, Chi square test, and also Anova and Tukey test, 5% of significance. There were no significant differences in push-out bond strengths among the different groups in the coronal (p = 0.49), middle (p = 0.28) or apical third (p = 0.09). Sealeapex and EndoRez groups showed significantly less remnants of filling material at coronal (p = 0.045) and apical levels (p = 0.006).Significant differences of chemical components remnants were found in AHP, IRT and SLP groups on apical third. It is concluded that residual endodontic filling material does not influence on the bond strength of fiberglass.
2
Gomes, Giovana Mongruel. "Influência do operador e agente cimentante na resistência de união de pinos de fibra de vidro à dentina radicular." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2010. http://tede2.uepg.br/jspui/handle/prefix/1757.
Full textAbstract:
Made available in DSpace on 2017-07-24T19:22:11Z (GMT). No. of bitstreams: 1
Giovana Mongruel Gomes.pdf: 1282438 bytes, checksum: 3923d5e2e659866f5b3a3e842b6cceb4 (MD5)
Previous issue date: 2010-02-22Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The aim of this study was to evaluate the influence of the operator skill and resin cement system on the bond strength (BS) of glass fiber post to radicular dentin in different root thirds. Forty-eight extracted human upper central incisors were sectioned transversally immediately below the cement-enamel junction and the roots were treated endodontically. After one week, standardized post space cavities were prepared, and the roots randomly divided into two groups (n=24), according to the operator skill: professional (CD) vs academic (AC). The roots were then subdivided into three subgroups (n=8) according to the cementation system: CD1 and AC1 (Adper Scotchbond Multi-Purpose [SBMP] + RelyX ARC [ARC]), CD2 and AC2 (Adper Single Bond 2 [SB] + ARC) and CD3 and AC3 (RelyX U100 [U100]). The glass fiber post (Tenax Fiber Trans Esthetic Post System) were cemented following the manufacturer’s instructions of each cementation system. After water storage at 37o C for one week, each root was sectioned transversely into six 1-mm thick discs and the coronal (TC), middle (TM) and apical (TA) thirds of the root canal identified. A push-out test was carried out at a crosshead speed of 0,5 mm/min. The data were statistically analyzed by ANOVA and post-hoc Tukey's tests (p=0.05). The mean bond strengths (BS) values (MPa) and standard deviations (SD) of each subgroup were: CD1: 12.83±7.26; CD2: 11.46±4.22; CD3: 14.27±6.59; AC1: 9.70±4.37; AC2: 8.02±5.25 and AC3: 13.40±4.93. The BS of the CD and AC groups were 12.85±6.18 and 10.37±5.30, respectively. In regard to the root thirds, the means and SD were: TC: 14.46±5.55; TM: 10.04±5.07 and TA: 10.35±6.01. The mean and SD for the cementation systems were: SBMP + ARC: 11.27±6.13; SB + ARC: 9.74±5.03 and U100: 13.83±5.77. The highest BS means were obtained for CD group (p=0.004); no significant differences were detected among the three cementation systems for CD group (p=0.294); U100 cement reached statistically higher BS than the other cementation systems for AC group (p=0.001). The resin cement U100 was statistically higher than the other materials (p=0.0010) regardless the operator skill. The BS in the cervical third was statistically higher than in the TM and TA (p<0.0001). It can be concluded that the bond strength to the root canal is significantly affected by the operator skill, cementation system and root region.
O propósito desse estudo foi avaliar a influência do operador e do sistema de cimentação na resistência de união (RU) de pino de fibra de vidro à dentina radicular nos diferentes terços radiculares. Quarenta e oito incisivos centrais superiores humanos extraídos foram seccionados transversalmente imediatamente após a junção cemento-esmalte, e as raízes foram tratadas endodonticamente. Após uma semana, foi realizado o preparo padronizado dos condutos, e as raízes foram aleatoriamente divididas em dois grupos (n=24), de acordo com o operador: profissional (CD) vs acadêmico (AC). As raízes foram então subdivididas em três subgrupos cada (n=8) de acordo com o sistema de cimentação: CD1 e AC1 (Adper Scotchbond Multi-Purpose [SBMP] + RelyX ARC [ARC]), CD2 e AC2 (Adper Single Bond 2 [SB] + ARC) e CD3 e AC3 (RelyX U100 [U100]). Os pinos de fibra de vidro (Tenax Fiber Trans Esthetic Post System) foram cimentados de acordo com as recomendações dos fabricantes de cada sistema de cimentação. Após o armazenamento em água a 37o C por uma semana, cada raiz foi seccionada transversalmente em seis discos com 1 mm de espessura, e os terços coronário (TC), médio (TM) e apical (TA) do canal radicular foram identificados. O teste de push-out foi realizado a uma velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente por meio do teste ANOVA e pós teste de Tukey (p=0,05). Os valores médios de RU (MPa) e desvio padrão (DP) para cada subgrupo foram: CD1: 12,83±7,26; CD2: 11,46±4,22; CD3: 14,27±6,59; AC1: 9,70±4,37; AC2: 8,02±5,25 e AC3: 13,40±4,93. A RU e DP para o grupo dos CD e dos AC foram 12,85±6,18 e 10,37±5,30, respectivamente. Em relação aos terços radiculares, as médias e o DP foram: TC: 14,46±5,55; TM: 10,04±5,07 e TA: 10,35± 6,01. As médias e DP para os sistemas de cimentação foram: SBMP + ARC: 11,27±6,13; SB + ARC: 9,74±5,03 e U100: 13,83±5,77. As maiores médias de RU foram obtidas para o grupo dos CD (p=0,004); não houve diferenças significativas entre os três sistemas de cimentação para o grupo dos CD (p=0,294); o cimento U100 foi estatisticamente superior aos demais sistemas de cimentação para o grupo dos AC (p=0,001). O cimento resinoso U100 foi estatisticamente superior aos demais sistemas de cimentação (p=0,001) independente do operador. A RU no terço coronário foi estatisticamente superior aos TM e TA (p<0,0001). Pode-se concluir que a resistência de união do canal radicular foi significativamente afetada pelo operador, sistema de cimentação e região radicular.
3
Villa, Felipe Augusto. "INFLUÊNCIA DA TRANSLUCIDEZ DE PINOS DE FIBRA DE VIDRO E TEMPO DE FOTOATIVAÇÃO DE UM CIMENTO DUAL NA RESISTÊNCIA DE UNIÃO À DENTINA RADICULAR." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2012. http://tede2.uepg.br/jspui/handle/prefix/1794.
Full textAbstract:
Made available in DSpace on 2017-07-24T19:22:21Z (GMT). No. of bitstreams: 1
Felipe Villa Verde.pdf: 899114 bytes, checksum: 339db35f81d16c1053ac909db81b72f5 (MD5)
Previous issue date: 2012-02-27Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The aim of this study was to evaluate in vitro through the push-out test, if the use of opaque glass fiber posts (Exacto – Angelus [PO]) and translucent (Exacto Translucent – Angelus [PT]), adhesively cemented into the root with dual resin cement (Variolink II - Ivoclar Vivadent) under different polymerization time had an influence on the bond strength in three different root canal thirds. Forty-eight singlerooted extracted human premolars were selected from the Tooth Bank UEPG for research. They had their crowns sectioned to form roots with 15 mm in length. All teeth received endodontic treatment and then were divided into 6 groups (n=8), to receive the cementation according to the type of glass fiber post (opaque vs.translucent) and the time of photoactivation of resin cement (20, 40 and 60 seconds). After storage in water at 37° C for one week, the teeth were embedded in acrylic resin and sectioned perpendicular to its long axis to form discs 1 mm thick, with two discs for each root third, and then were taken to the machine universal testing. The push-out test was performed at a speed of 0.5 mm/min. The data were statistically analyzed by ANOVA and Tukey's test (p = 0.05). The mean values of bond strength (MPa) and standard deviation (SD) for groups in the cervical third, middle and apical regions were: PO20 - 21.02 ± 3.52, 15.83 ± 4.94 and 5.20 ± 10:48; PO40 - 14.42 ± 3.98, 12.12 ± 4.40 and 11.59 ± 4.89; PO60 - 16.27 ± 7.14, 13.33 ± 5.22 and 16.99 ± 7.82; PT20 - 18.34 ± 5.47, 10.83 ± 4.63 and 9.98 ± 4.76; PT40 - 17.51 ± 6.55, 14.06 ± 3.85 and 10.95 ± 4.65; PT60 - 19.42 ± 5.86, 15.35 ± 5.43 and 12.77 ± 5.93). There were no significant differences between the types of fiber posts used and the different times of polymerization (p>0.05) in relation to the root area were statistically significant differences only between the cervical and the other thirds (p>0.05). It can be concluded that the bond strength of the root canals was not affected by the type of glass fiber post (opaque vs. translucent) and photoactivation time.
O objetivo deste estudo in vitro foi avaliar por meio do teste de push-out, se a utilização de pinos de fibra de vidro opaco (Exacto – Angelus [PO]) e translúcido (Exacto Translúcido – Angelus [PT]), cimentados adesivamente no canal radicular com cimento resinoso de presa dual (Variolink II – Ivoclar Vivadent) sob diferentes tempos de fotoativação apresentavam influência na resistência de união nos três diferentes terços do canal radicular. Quarenta e oito pré-molares unirradiculares humanos extraídos foram selecionados no Banco de Dentes da UEPG para a pesquisa. Tiveram suas coroas seccionadas para formar raízes com 15 mm de comprimento. Todos os dentes receberam tratamento endodôntico e em seguida foram divididos em 6 grupos (n=8), para receber a cimentação de acordo com o tipo de pino de fibra de vidro (opaco vs translúcido) e com o tempo de fotoativação do cimento resinoso (20, 40 e 60 segundos). Após o armazenamento em água a 37o C por uma semana, os dentes foram embutidos em resina acrílica e seccionados perpendicularmente ao seu longo eixo para formar discos de 1 mm de espessura, sendo 2 discos para cada terço radicular, e em seguida foram levados à máquina de ensaios universal. O teste de push-out foi realizado a uma velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente por meio do teste ANOVA e pós-teste de Tukey (p=0,05). Os valores médios de RU (MPa) e desvio padrão (DP) para os grupos nos terços cervical, médio e apical foram respectivamente: PO20 – 21,02 ± 3,52, 15,83 ± 4,94 e 10,48 ± 5,20; PO40 – 14,42 ± 3,98, 12,12 ± 4,40 e 11,59 ± 4,89; PO60 – 16,27 ± 7,14, 13,33 ± 5,22 e 16,99 ± 7,82; PT20 – 18,34 ± 5,47, 10,83 ± 4,63 e 9,98 ± 4,76; PT40 – 17,51 ± 6,55, 14,06 ± 3,85 e 10,95 ± 4,65; PT60 – 19,42 ± 5,86, 15,35 ± 5,43 e 12,77 ± 5,93. Não foram observadas diferenças significativas entre os tipos de pino de fibra utilizados e os diferentes tempos de fotoativação (p > 0,05); em relação à região radicular foram encontradas diferenças estatisticamente significativas somente entre o terço cervical e os demais terços (p > 0,05). Pode-se concluir que a resistência de união do canal radicular não foi afetada pelo tipo de pino de fibra de vidro (opaco vs translúcido) e tempo de fotoativação. O objetivo deste estudo in vitro foi avaliar por meio do teste de push-out, se a utilização de pinos de fibra de vidro opaco (Exacto – Angelus [PO]) e translúcido (Exacto Translúcido – Angelus [PT]), cimentados adesivamente no canal radicular com cimento resinoso de presa dual (Variolink II – Ivoclar Vivadent) sob diferentes tempos de fotoativação apresentavam influência na resistência de união nos três diferentes terços do canal radicular. Quarenta e oito pré-molares unirradiculares humanos extraídos foram selecionados no Banco de Dentes da UEPG para a pesquisa. Tiveram suas coroas seccionadas para formar raízes com 15 mm de comprimento. Todos os dentes receberam tratamento endodôntico e em seguida foram divididos em 6 grupos (n=8), para receber a cimentação de acordo com o tipo de pino de fibra de vidro (opaco vs translúcido) e com o tempo de fotoativação do cimento resinoso (20, 40 e 60 segundos). Após o armazenamento em água a 37o C por uma semana, os dentes foram embutidos em resina acrílica e seccionados perpendicularmente ao seu longo eixo para formar discos de 1 mm de espessura, sendo 2 discos para cada terço radicular, e em seguida foram levados à máquina de ensaios universal. O teste de push-out foi realizado a uma velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente por meio do teste ANOVA e pós-teste de Tukey (p=0,05). Os valores médios de RU (MPa) e desvio padrão (DP) para os grupos nos terços cervical, médio e apical foram respectivamente: PO20 – 21,02 ± 3,52, 15,83 ± 4,94 e 10,48 ± 5,20; PO40 – 14,42 ± 3,98, 12,12 ± 4,40 e 11,59 ± 4,89; PO60 – 16,27 ± 7,14, 13,33 ± 5,22 e 16,99 ± 7,82; PT20 – 18,34 ± 5,47, 10,83 ± 4,63 e 9,98 ± 4,76; PT40 – 17,51 ± 6,55, 14,06 ± 3,85 e 10,95 ± 4,65; PT60 – 19,42 ± 5,86, 15,35 ± 5,43 e 12,77 ± 5,93. Não foram observadas diferenças significativas entre os tipos de pino de fibra utilizados e os diferentes tempos de fotoativação (p > 0,05); em relação à região radicular foram encontradas diferenças estatisticamente significativas somente entre o terço cervical e os demais terços (p > 0,05). Pode-se concluir que a resistência de união do canal radicular não foi afetada pelo tipo de pino de fibra de vidro (opaco vs translúcido) e tempo de fotoativação.
4
Ferreira, Reinaldo de Souza. "Influência do sistema de cimentação e do modo de ativação na resistência ao push-out de pinos de fibra de vidro." Universidade do Estado do Rio de Janeiro, 2009. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=2520.
Full textAbstract:
O objetivo deste estudo foi avaliar a influência do tipo de sistema de cimentação (condicionamento ácido total ou autoadesivo), do modo de ativação (autoativado ou dual), do terço do conduto radicular (cervical, médio ou apical) e da espessura do filme de cimento sobre a resistência de união de pinos de fibra de vidro cimentados em dentes humanos. Quarenta raízes foram incluídas em resina epóxi, submetidas a tratamento endodôntico e obturadas com guta percha e cimento endodôntico sem eugenol. Decorridos sete dias, os condutos foram preparados a uma profundidade de 10mm com brocas padronizadas do sistema dos pinos de fibra (WhitePost DC #2) e aleatoriamente divididos em 4 grupos, conforme o sistema de cimentação e o modo de ativação: (G1) RelyX ARC/Adper Scotchbond Multi-Purpose Plus (condicionamento ácido total), ativação dual, (G2) RelyX ARC/Adper Scotchbond Multi-Purpose Plus, autoativado, (G3) RelyX U100 (autoadesivo), dual e (G4) RelyX U100, autoativado. Após uma semana, cada raiz foi seccionada em máquina de corte, originando 6 fatias de 1 mm de espessura (n=60). Antes do ensaio de push-out cada fatia foi fotografada em ambas as faces, para determinação do raio dos pinos e da espessura do filme de cimento. Após o ensaio mecânico, novas imagens foram capturadas para determinação do modo de falha. Para automatizar a determinação da espessura de cimento, foi desenvolvida uma macro no software KS 400. Os dados foram estatisticamente analisados com ANOVA 3 fatores (resistência de união) e teste de Kruskall-Wallis (espessura do cimento). Comparações múltiplas foram realizadas com o teste Student-Newman-Keuls. Análise de regressão, modelo linear, foi empregada para verificar a correlação entre espessura do cimento e resistência de união. Todos os testes foram aplicados com α = 0,05. O fator cimento exerceu influência significativa para a resistência de união (p = 0,0402): o RelyX U100 apresentou a maior média. A ativação dual elevou os valores de resistência de união em comparação ao modo quimicamente ativado (p < 0,0001). Houve diferenças significantes entre os grupos, sendo G1 (22,4 4,0 MPa) > G3 (20,4 3,6 MPa) > G4 (17,8 5,2 MPa) > G2 (13,5 4,3 MPa). O terço do conduto não exerceu influência significativa sobre a resistência adesiva (p = 0,4749). As espessuras dos filmes de cimento foram estatisticamente diferentes nos diferentes terços: cervical (102 45 m) > médio (75 29 m) > apical (52 28m). Não foi observada forte correlação entre os valores de espessura e os de resistência ao push-out (r = - 0,2016, p = 0,0033). O tipo de falha predominante foi a mista, exceto para o G2, que apresentou 74% das falhas na interface cimento-pino. Dessa forma, o cimento autoadesivo apresentou melhor desempenho que o convencional, e ambos os sistemas duais, sobretudo o RelyX ARC, apresentaram dependência da fotoativação para atingirem maiores valores de resistência de união.The aim of this study was to evaluate the influence of adhesive cementation system approach (total-etch or self-adhesive), activation mode (self-cure or dual-cure), canal third (cervical, middle or apical) and cement thickness on push-out bond strength of glass fiber post bonded on human roots. Forty roots were embebed in epoxy resin and endodontically treated (filled with guta percha and non-eugenol endodontic sealer). Following 7 days, the post spaces were prepared with low-speed post drills provided by the manufacturer (WhitePost DC #2, FGM) at a depth of 10 mm and the roots were randomly divided in 4 groups, according to cementation system and activations mode: (G1) RelyX ARC/Adper Scotchbond Multi-Purpose Plus (total-etch), dual-cure (G2) RelyX ARC/Adper Scotchbond Multi-Purpose Plus, self-cure, (G3) RelyX U100 (self-adhesive), dual-cure and (G4) RelyX U100, self-cure. After 7 days, each root was sectioned with water-cooled diamond blade, generating six 1-mm thickness slices (n=60). Before push-out bond strength test, digital images of both sides of the slices were captured with digital camera, in order to measure the post radius and the cement thickness. After mechanical test, new images were captured to evaluate the failure mode. A macro was developed in KS 400 software to speed and standardize the evaluation of cement thickness. Results were analyzed using three-way ANOVA (push-out) and Kruskall-Wallis test (cement thickness). Post-hoc multiple comparisons were performed using the Student-Newman-Keuls test. The correlation between resin cement thickness and bond strength was evaluated with regression analysis, linear model. All tests were performed with significance level set at 0.05. Push-out bond strength was significantly influenced by cement type (p= 0.0402): the RelyX U100 cement presented higher mean value. The dual-activated mode increased the bond strength in comparison to self-activated mode (p < 0.0001). Statically differences were observed between groups: G1 (22.4 4.0 MPa) > G3 (20.4 3.6 MPa) > G4 (17.8 5.2 MPa) > G2 (13.5 4.3 MPa). Bond strength was not affected by post space depth (p = 0,4749). The resin cement thicknesses were significantly different in root thirds: cervical (102 45 m) > middle (75 29 m) > apical (52 28m). No strong correlation between cement thickness and push-out bond strength was observed (r = - 0.2016, p = 0.0033). The main failure mode was mixed, except for G2 (74% adhesive failures at post-cement interface). It was concluded tha the self-adhesive cement showed a better performance than the conventional one, and both dual resin systems, specially the RelyX ARC, presented photo-activation dependence to attain greater adhesive bond strength.
5
Salas, Mabel Miluska Suca. "Influência da viscosidade do condicionador ácido na dentina radicular sobre a resistência de união de um sistema de cimentação adesivo. Avaliação por teste de push-out e MEV." Universidade Federal de Pelotas, 2005. http://repositorio.ufpel.edu.br/handle/ri/2308.
Full textAbstract:
Made available in DSpace on 2014-08-20T14:30:20Z (GMT). No. of bitstreams: 1
Mabel Salas_DISSERTACAO.pdf: 6552657 bytes, checksum: 11efe494170784ff76d8fc2f0dff8e56 (MD5)
Previous issue date: 2005-06-10Actually different alternatives to restored teeth with endodontical treatment are propose, otherwise with the advented of adhesive systems their use as luting endodontical cements and bonding resin cement for fiber posts are common. However the inherent characteristics behavior of these materials and the different variances presented at root canal, turns them sensible to failure. The aime of the study was to evaluated: a) the influence of two luting cements: containing eugenol (Endofill) and containing resin materials (Ahplus) on dentin bonding strength using push-out test at cervical, medium and apical root dentin regions, using two different 37% phosphoric acid viscosities: gel and liquid: b) the effect of the total-etching acid process on the pattern observed of the conditioned dentine substrate, c) Characterize the dentinal surface at different root regions d) Classify the fracture patterns between the substrate and the resin cement at three root regions. One hundred and four uniradicular teeth without caries lesions, extracted by orthodontics or periodontal reasons, with 7mm of diameter and 14mm of length were selected, disinfected in 0,5% chloramine and storage in distillated water at 5ºC. Endodontical canal treatments were performed using the Step-back technique and obturated with Endofill and AHplus. The preparation of the post space was 11mm depth using standardized rotary instruments. The total-etching with the gel and liquid acid were performed. The fiber posts were marked at the same depth, cuted, dry and silanized. Then two coats of Prime&bond 2,1 previously mixed with the self-cure activator, were applied at the post surface and into de root canal, after 1 minute the post were photocured (halogen light intensity of 450mW). The resin cement was mixed and placed into de canal using a lentuloespiral instrument. The posts were placed and a static force of 5kg for 10 minutes were applied, after words both adhesive and cement were photocured for 40 seconds, storage for 24 h in 37ºC, and embedded in a poliestyren resin. Cross-sectional cuts were obtained for the push-out test. The test were performed at a crosshead speed of 0,5mm/min, and a plane 20 cylindrical point was applied at the post centre. The maxim load was calculated in Mpa. The adhesive area was calculated using a tapered-cone shaped formula. The results were subjected to statistical analysis using a ANOVA test for multiple variables and a Pos Doc test(p<0,05) Statistically significant differences were detected between all the evaluated criterias: acids, cements and regions, and when they were inter-relationated between them. It was concluded that the use of 37% of phosphoric acid in a liquid form, allows a better penetration into the root canal, a uniform decalcification, consequently enhancing the bonding strength of the root dentine, particularly at apical region.
Actualmente diversos tipos de alternativas para restaurar dentes submetidos a tratamento endodontico são propostos, dentre estes, sistemas adesivos resinosos cimentantes para uso endodontico e pinos de fibra. No entanto as carateristicas inerentes apresentadas por estes materiais e as diversas variáveis presentes em nível radicular os fazem sensíveis a falhas. O objetivo deste trabalho foi avaliar a influência do tipo de cimento endodôntico e da viscosidade do ácido sobre a resistência de união de um sistema adesivo utilizando pinos de fibra de vidro, mediante o teste push-out e MEV em três níveis radiculares: cervical, médio e apical. Foram selecionados 104 dentes uniradiculares sem cárie, extraídos por motivos periodontais ou ortodônticos. Os dentes foram desinfectados em cloramina 0,5% e armazenados em água destilada a 5ºC. Os tratamentos endodônticos foram padronizados com a técnica step-back, obturando-se com Ahplus ou com Endofill. Os preparos para os pinos foram de 11mm padronizando os instrumentos. O condicionamento com o ácido fosfórico a 37%, em gel ou em líquido, foi realizado em ambos grupos. Os pinos de vidro foram seccionados em 11 mm,, silanizados, cobertos com duas camadas de Prime&bond 2.1 misturado previamente com o ativador de autopolimerização. O cimento resinoso Enforce (Dentsply) foi misturado e aplicado no canal utilizando lentulo. O pino era inserido e aplicava-se uma força padronizada de 5kg durante 10 min e sendo polimerizados por 40 seg, e armazenados por 24 horas a 37ºC, incluídos em resina de polietileno, cortados em 6 discos transversais de 1,5mm e lixados. O teste de push-out foi com uma velocidade de 0,5 mm/min, a ponta ativa cilíndrica plana (0,9 mm de diâmetro) era aplicada no centro do pino. A carga máxima foi convertida em MPa.. As diferenças entre os grupos foram determinadas mediante a análise de variância de ANOVA de três critérios, teste de Post Hoc (p<0,05). De acordo com a análise de fratura foram observadas diferenças nos três terços estudados particularmente no terço apical. Segundo a análise de fratura, foram observados quatro padrões diferentes de fraturas. Todas as variáveis testadas influenciaram significativamente a 18 resistência de união. A região cervical produziu geralmente menores valores de união, quando era utilizado o ácido em gel. Por outro lado, quando era utilizado o ácido em líquido os valores de resistência aumentavam, podendo-se concluir que a utilização de ácido fosfórico 37% em líquido permite uma maior penetração do adesivo no canal radicular produzindo um aumento da resistência de união na dentina radicular, particularmente no terço apical.
6
Ruiz, Lucas Manuel. "EFEITO DE CIMENTOS ENDODÔNTICOS NA RESISTÊNCIA DE UNIÃO DE PINOS DE FIBRA DE VIDRO À DENTINA RADICULAR." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2012. http://tede2.uepg.br/jspui/handle/prefix/1796.
Full textAbstract:
Made available in DSpace on 2017-07-24T19:22:21Z (GMT). No. of bitstreams: 1
lucas m ruiz.pdf: 809225 bytes, checksum: 4f9a5e3d41d46a1259de31458f886bd4 (MD5)
Previous issue date: 2012-02-27Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The purpose of this study was to evaluate the influence of root canal sealers on the bond strength (BS) of glass fiber posts to root dentin using two cementation systems, two storage periods and the different root regions. It was used 56 human teeth,healthy canines, transversely sectioned immediately after the cement-enamel junction. Then the roots were divided into two groups (n = 28) according to the sealer (with or without eugenol [Endofill and Sealer 26, respectively]). Subsequently, the roots were subdivided into two subgroups each (n = 14) according to the period of storage before the adhesive cementation, 7 and 180 days. Each subgroup was further again subdivided according to the resin cement to be used, being a conventional dual resin cement (Variolink® II ) and a dual adhesive system (Excite DSC), and the other a dual resin cement autoconditioning and self-adhesive (RelyX™ U100). The glass fiber posts (White Post DC) were cemented according to manufacturer's instructions for each cementation system. All roots were stored for one week after adhesive cementation, and were subsequently sectioned transversely into six discs about 1 mm thick each, and the coronal (CT), middle (MT) and apical (AT) thirds of the root canal identified. The push-out test was carried out at a crosshead speed of 0.5 mm/min. The data were statistically analyzed by ANOVA factorial and post-hoc Tukey`s test (p=0.05). The analysis of variance showed a statistically significant effect for the factors time (F=6.58, p=0.01) and root third (F=26.67, p=0.0005). The specimens that received intra-canal posts 6 months after the endodontic treatment had higher BS than the specimens treated 7 days after endodontic treatment. The AT showed statistically lower BS than those of CT and MT. It can be concluded that the bond strength of fiber posts to root dentin was not affected by the root canal sealers and cementation systems.
O propósito deste estudo foi avaliar a influência dos cimentos endodônticos na resistência de união (RU) de pinos de fibra de vidro à dentina radicular, utilizando dois sistemas de cimentação, dois períodos de armazenamento e as diferentes regiões radiculares. Foram utilizados 56 dentes humanos, caninos hígidos, seccionados transversalmente imediatamente após a junção cemento-esmalte. Em seguida, as raízes foram divididas em dois grupos (n=28) de acordo com o cimento endodôntico (com ou sem eugenol [Endofill e Sealer 26, respectivamente]).Posteriormente, as raízes foram subdivididas em dois subgrupos cada (n=14) de acordo com o período de armazenamento antes da cimentação adesiva, sendo 7 e 180 dias. Cada subgrupo foi novamente subdividido de acordo com o cimento resinoso a ser utilizado sendo um cimento resinoso convencional dual (Variolink II) e sistema adesivo dual (Excite DSC), e outro cimento resinoso dual auto condicionante e auto adesivo (RelyX U100). Os pinos de fibra de vidro (White Post DC) foram cimentados de acordo com as instruções do fabricante de cada sistema de cimentação. Todas as raízes foram armazenadas por uma semana após a cimentação adesiva, e posteriormente seccionadas transversalmente em seis discos de aproximadamente 1 mm de espessura cada, e os terços coronário (TC), médio (TM) e apical (TA) do canal radicular foram identificados. O teste de push-out foi realizado a uma velocidade de 0,5 mm/min. Os dados obtidos foram analisados estatisticamente por meio do teste ANOVA fatorial e pós teste de Tukey (p=0,05). A análise de variância demonstrou um efeito estatisticamente significante para os fatores tempo (F=6,58; p=0,01) e terço radicular (F=26,67; p=0,0005). Os espécimes que receberam pino intra-canal após 6 meses do tratamento endodôntico apresentaram maior RU do que os espécimes tratados após 7 dias do tratamento endodôntico. O TA demonstrou valores de RU estatisticamente inferiores às dos TC e TM. Pode-se concluir que a resistência de união dos pinos de fibra à dentina radicular não foi afetada pelos cimentos endodônticos e sistemas de cimentação.
7
Sánchez, Johanna Lizbeth Cuadros. "EFEITO DA APLICAÇÃO SÔNICA DE SISTEMAS ADESIVOS NA ADESÃO DE PINOS DE FIBRA DE VIDRO NO CANAL RADICULAR." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2014. http://tede2.uepg.br/jspui/handle/prefix/1835.
Full textAbstract:
Made available in DSpace on 2017-07-24T19:22:33Z (GMT). No. of bitstreams: 1
Johanna Lizbeth Cuadros Sanchez.pdf: 3888267 bytes, checksum: abbdebf22c3a3a8b49c91f6bc734b34d (MD5)
Previous issue date: 2014-02-26Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Abstract: Luting of posts inside the root canal is still a challenge because of the difficult to bonding mainly in the apical third. The aim of this study was evaluate the influence of the application of 3 simplified total-etch adhesive systems (Adper Single Bond 2 Ambar, and XP-Bond+self-cure activator) under manual mode or sonic vibration on the push-out bond strength (POBS), silver nitrate uptake (SNU) and in situ degree of conversion (ISDC) associated to resin cement when used for luted posts. Methods: The roots of 66 human premolars were prepared and divided into six groups (n=11), according to the following combination: adhesive and application mode. The posts were cemented in accordance with the manufacturer’s instructions of each cementation system. After water storage, the roots were sectioned transversely into six slabs and it were tested in POBS (0.5mm/min). Two roots for group were data were immersed in 50% silver nitrate, photo-developed and analyzed by SEM to measure the SNU. Two roots for group were evaluated by micro-Raman spectroscopy to measure ISDC. The data were analyzed by 3-way repeated measures ANOVA and Tukey's tests (5%). Results: When sonic application was performed, usually there are a significantly increasing on the POBS (MPa) (35% and 37% respectively) and ISDC (%) (14% and 38% respectively in the medium and apical thirds) and decreasing of SNU (%) for all groups mainly in the medium (64% decreasing) and apical (84%) thirds when compared with manually application (P < 0.05).
Resumo: A cimentação de pinos dentro do canal radicular ainda é um desafio por causa das dificuldades relativas à adesão, principalmente no terço apical. O objetivo deste estudo foi avaliar a influência da aplicação de três sistemas adesivos convencionais simplificados (Adper Single Bond 2, Ambar e XP-Bond + self cure ativator) manualmente ou através de um dispositivo sônico vibratório na resistência de união por push-out (RU), na infiltração de nitrato de prata (NI) e no grau de conversão in situ (GC) associado ao cimento resinoso de cada fabricante, quando utilizado para cimentação de pinos. Métodos: As raízes de 66 pré-molares humanos foram preparadas e divididas em seis grupos (n = 11), de acordo com a seguinte combinação: adesivo/cimento e modo de aplicação. Os pinos foram cimentados de acordo com as instruções do fabricante de cada sistema de cimentação apenas variando o modo de aplicação. Depois do armazenamento em água, as raízes foram seccionadas transversalmente em seis fatias e foram testados em RU (0,5 mm/min). Duas raízes por grupo foram imersas em 50% de nitrato de prata, e após revelação, foram analisadas por MEV para medir a NI. Duas raízes por grupo foram avaliadas por espectroscopia de micro-Raman para medir GC. Os dados foram analisados por análise de variância de 3 fatores de medidas repetidas (terço radicular) e teste de Tukey (5%). Resultados: Quando a aplicação sônica vibratória foi utilizada, em geral, se observou um aumento significativo na RU (MPa) (35% e 37% respectivamente) e GC (%) (14% e 38% respectivamente nos terços médio e apical) e diminuição da NI (%) para todos os grupos, principalmente nos terços médio (redução de 64%) e apicais (84%) quando comparada com a aplicação manual (p <0,05) e este fenômeno ocorreu para todos os sistemas adesivos/cimentos testados.
8
Montero, Eduardo. "Protocolos para a colocação e remoção de espigões." Master's thesis, 2016. http://hdl.handle.net/10284/5577.
Full textAbstract:
A utilização de espigões em dentes tratados endodonticamente é um dos temas mais
estudados em Medicina Dentária. As opiniões são divergentes em relação aos
procedimentos clínicos e materiais a serem utilizados para a colocação e remoção de
espigões. O objetivo deste trabalho foi realizar uma revisão bibliográfica de forma a
organizar conceitos e princípios clínicos para melhor esclarecer os fatores que determinam
a necessidade de colocação, utilização e escolha do tipo de espigão, sua cimentação e
técnicas para a remoção. Foram analisadas as características e propriedades dos cimentos
de fosfato de zinco, ionômero de vidro, cimentos resinosos de polimerização química,
polimerização dupla, foto-polimerizável e os sistemas adesivos etch and rinse, self etch e
autoadesivos, bem como as técnicas para a remoção de espigões cimentados com diferentes
cimentos e sistemas adesivos para depois acessar o remanescente de guta percha para o
retratamento endodôntico. Foi feita uma pesquisa bibliográfica na base de dados electrónica
PubMed, Google Scholar e RCAAP com as seguintes palavras chave: “Espigões”;
“Retratamento Endodôntico”; “Ionómero de Vidro”; “Fosfato de Zinco”; “Cimentos
Resinosos”; “Posts”; “Endodontic Retreatment”; “Glass Ionomer”; Zinc-phosphate”;
“Resin Cements"; “Push Out Test”; “Posts AND Removal”. Concluiu-se que a cimentação
de espigões pré-fabricados de fibra de vidro com cimentos resinosos de dupla
polimerização associados aos sistemas adesivos self etch estão gradualmente substituindo
os outros tipos de espigões e demais cimentos e possibilitam restaurar o dente de forma
adequada e duradoura. E o uso de ultrassons apresenta maior eficácia e segurança na
remoção dos espigões.The use of Posts in endodontically treated teeth is one of the most studied topics in dentistry. Opinions are divergent with respect to clinical procedures and materials to be used for placement and removal of Posts. The aim of this study was a literature review order to arrange concepts and clinical principles to clarify the factors that determine the need for placement, use and choose to Post type, your cementation and techniques for removal. The characteristics and properties of zinc phosphate cement, glass ionomer, resin cements chemical curing, dual curing, photo-curing and etch and rinse, self etch and self adhesive bonding agents were analyzed. Also, techniques for removing Posts cemented with different cements and adhesive systems and then access the remaining “gutta-percha” for the endodontic retreatment. A literature search was made in the electronic database PubMed, Google Scholar e RCAAP with the following keywords: “Espigões”; “Retratamento Endodôntico”; “Ionómero de Vidro”; “Fosfato de Zinco”; “Cimentos Resinosos”; “Posts”; “Endodontic Retreatment”; “Glass Ionomer”; Zinc-phosphate”; “Resin Cements"; “Push Out Test”; “Posts AND Removal”. It was concluded that the cement fiber Posts with resin cements dual curing associated with the self etch adhesive systems are gradually replacing other types of Posts and other cements and allow restoring the tooth proper and lasting manner. And the use of ultrasound is more effective and safe Posts removal.
Books on the topic "Pushto Poets"
1
Ṭakor, Afz̤al. Dā līkwāl aw dā ṡeray. [Kabul]: Da Nashrāto Riyāsat, da Chāp aw Khaparwuno Dawlatī Kumītah, 1987.
Find full text
2
Ḥabībī, ʻAbd al-Ḥayy. Pushtānah shuʻarāʼ. Peṣhawar: Yūnīwarsiṭī Buk Ejansī, 1992.
Find full text
3
Yūsufzai, Mushtāq Majrūḥ. Ház̲ā mā kanaztum, naqd 1418: Da Puṣhto yaw taḥqiqī aw tanqidī lik. [S.l: s.n.], 1997.
Find full text
4
Āfrīdī, Khāt̤ir. Da Khāt̤ir Āfrīdī kulliyāt. Peṣhawar: Da Mundalo darakūnah, Yūnīwarsiṭī Buk Ejansī, 1999.
Find full text
6
Shinwārī, Amīr Ḥamzah Ḥamzah. Dāstān-i Amīr Ḥamzah Shinvārī. Pishāvar: Sinḍīkeṭ āf Rāʾiṭarz Pākistān, 1996.
Find full text
7
Yawn, Ismāʻīl. Da Muḥammad Gul Khān Momand wa zhwand tah yaw lanḍah katnah. [Peshawar]: Da Khwushḥāl Farhangī Ṭolanah, 1994.
Find full text
8
G̲h̲aznavī, K̲h̲āt̤ir, ed. Dāstān-i Amīr Ḥamzah Shinvārī. Pishāvar: Sinḍīkeṭ āf Rāʼiṭarz Pākistān, 1996.
Find full text
9
Shāh, Ṣābir Sayyid Ṣābir, ed. Da Ustād Rūhī yād. Peṣhawar: Yūnīwarsiṭī Buk Ejansī, 1997.
Find full textBook chapters on the topic "Pushto Poets"
1
Sinichkina, Daria. "Entre mythe et histoire, syncrétisme et fracture, universalité et russité: le recueil Mednyj Kit (Baleine de bronze) au coeur de l’esthétique révolutionnaire de Nikolaj Kljuev." In Biblioteca di Studi Slavistici, 235–57. Florence: Firenze University Press, 2017. http://dx.doi.org/10.36253/978-88-6453-507-4.18.
Full textAbstract:
Soon after greeting the February revolution, Klyuev turns to an aesthetic of violence and disruption. In the poetic cycle Medny Kit (1918), the utopia of “peasant paradise” stems from the apocalyptic destruction of old Russia. While the poet contemplates the cyclicity of Russian history, the lyrical subject comes transfigured out of the “red” baptism, identifying himself simultaneously to Rasputin and Avvakum. As the cycle captures the brutal melody of the times, the lyric genre is pushed to its limit – polyphony, which announces the transition to narrative and epic poetry.
2
Nana, A., and Sasa Hajzler. "Life of Migrants on the Balkan Road to Europe - Selected Poems From a Migrant's Diary of Resistance." In Edition Politik, 90–95. Bielefeld, Germany: transcript Verlag, 2024. http://dx.doi.org/10.14361/9783839470558-013.
Full textAbstract:
A., a persecuted activist, flees Cameroon to Europe. In 2019 he is extradited by the Slovenian police and brutally pushed back by Croatian border police. A. takes the state of Slovenia to court with the help of from a local Slovenian activist group, Infokolpa. Over the several years that follow, as he waits for the outcome of the court case, he writes a diary and collects testimonies from other migrants in camp Miral in Bosnia, creating a poetry of resistance. This contribution consists of excerpts of his poetry. The words belong to A., but the voice is of all migrants
3
Lee-Ong, Alembert, and Alfred Allen Buenafe. "Instrumentations and Access Devices." In Mastering Endo-Laparoscopic and Thoracoscopic Surgery, 51–59. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-3755-2_9.
Full textAbstract:
AbstractMinimally Invasive Surgery (MIS) instruments are patterned after conventional hand instruments to perform similar specific functions; they are designed to pass and perform through small diameter ports and at a distance to the target tissues. The development of instruments has evolved since the early period of MIS, starting from the use of rudimentary gynecologic instruments; at that time. Gynecology was the only specialty widely performing laparoscopic procedures. The evolution in design, ergonomics, and variety has been pivotal for advancing endo-laparoscopic surgery to perform more complex surgical procedures with safety and better outcome. Various evolving concepts of MIS like Single-site or reduced Surgery, Natural Orifice Transluminal Endoscopic Surgery (NOTES), Needlescopic Surgery, and Robotic-assisted Surgery have also pushed the development of features such as articulation control, pre-bent configuration, smaller diameter, and robotic instruments to meet specific needs.
4
Hancock, James F. "Age of expansion." In Spices, scents and silk: catalysts of world trade, 264–77. Wallingford: CABI, 2021. http://dx.doi.org/10.1079/9781789249743.0020.
Full textAbstract:
Abstract When the Dutch and English first entered the Indian Ocean, the primary goal of both nations was to gain a monopoly in the spice trade. To do this, they had to militarily push out the Portuguese and prevent the other from gaining a foothold. Ultimately, the VOC came out the big Winner taking control of the clove, nutmeg and mace trade of the Moluccas. It also took a considerable portion of the Indonesian pepper trade by force, but not all. With the loss of the Spice Islands, the British shifted their attention to India and its pepper, saltpetre, cotton and indigo. The VOC also turned its eyes to India, but with far less lasting impact. To gain their foothold in India the English and Dutch were faced with two significant challenges: they would need to gain the favour of the Mughals who now controlled most of North India and they would have to push back the Portuguese who were well entrenched along the west coast. The Mughals had left the Portuguese ports mostly alone, preferring to trade with them rather than fight.
5
Rann, James. "Russian Poetry and the Rewilding of Scottish Literature." In Translating Russian Literature in the Global Context, 253–80. Cambridge, UK: Open Book Publishers, 2024. http://dx.doi.org/10.11647/obp.0340.15.
Full textAbstract:
This chapter borrows the metaphor of ‘rewilding’ from contemporary ecology to describe the effect of Russian poetry translated into Scots on the literature of Scotland in the past century. In that time, it is argued, poets writing in Scots have treated Russia as a source of unorthodox, revolutionary energy that might help them push back against anglophone monoculture and revitalize Scottish letters. I divide this history into three periods: the first is the modernist ‘Scottish Renaissance’ of the 1920s, in which the iconoclastic Hugh MacDiarmid made versions of Aleksandr Blok, Zinaida Gippius and others part of his interrogations of and prescriptions for Scottish national identity and language; the second is the 1960s and 1970s, when modernism slipped into postmodernism and when the presiding figure was the prolific and playful Edwin Morgan, who maintained a lifelong interest in the poetry of Vladimir Maiakovskii; I close with the period between the fall of the Soviet Union and the present, in which no single figure or explicit ideology has dominated, except perhaps for a growing concern with the promotion of minority identities as an end in itself. In all three periods, we see translators using Russian poetry, and especially experimental modernist verse, to help them interrogate Scotland’s ambivalent position as both perpetrator and victim of colonialism and to explore the productive tension between locally and globally dominant English and its minoritized sister-language Scots.
6
Araújo, A. I., M. Martins, J. C. Reis Campos, A. Barros, A. Azevedo, and T. Oliveira. "Influence of the Er,Cr:YSGG laser and radial firing tips on the push-out bond strength of glass fiber posts." In Biodental Engineering V, 95–100. London, UK; Boca Raton, FL: Taylor & Francis Group, [2019] |: CRC Press, 2019. http://dx.doi.org/10.1201/9780429265297-19.
Full text
7
Pellicanò, Domenica Savia, and Maria Rosaria Trecozzi. "Methodologies for Sustainable Development of TEN-T/RFC Corridors and Core Ports: Public Incentives for Industrial Activities Location in Port Related Areas." In Computational Science and Its Applications – ICCSA 2023 Workshops, 635–46. Cham: Springer Nature Switzerland, 2023. http://dx.doi.org/10.1007/978-3-031-37123-3_44.
Full textAbstract:
AbstractThe Special Economic Zone (SEZ) is a regulated area where industrial activities are facilitated and have many incentives in order to become more competitive and attractive. The establishment of a SEZ is the responsibility of the national government which provides a model based on specific measures to attract investment. The local administrations have to define a plan, according to the national model, for the development of the SEZs in order to respect and enhance the peculiarities of each area. The goal is to push the strategic connection among logistics, industry and ports through incentive packages, including fiscal and non-fiscal ones, in order to have strong repercussions on economic development.The impacts of the SEZs can be assessed in terms of sustainability: social, environmental and economic. In relation to economic sustainability, the paper proposes a general model developed to estimate the financial burdens borne by the regional and national administrations deriving from the establishment of the SEZ. The paper introduces a test case of Calabria Region to estimate the financial burdens necessary for the SEZ establishment in the Gioia Tauro macro-node, into the TEN-T core network and the RFC.
8
Lloyd, David. "New Things That Have Happened: Forms of Irish Poetry." In Counterpoetics of Modernity, 113–33. Edinburgh University Press, 2022. http://dx.doi.org/10.3366/edinburgh/9781474489805.003.0006.
Full textAbstract:
The academic critical industry has tended to promote a very conventional Irish lyric practice since the 1970s, with scant regard to the pressures that either the spectacular political violence or the “slow violence” of neoliberal capitalist development during recent decades have placed on the forms and language of poetry. The chapter focuses on three poets whose work has pushed against the constant reproduction of “well-made poems”: Ciaran Carson, Medbh McGuckian and Catherine Walsh.
9
Zellinger, Elissa. "The Poetess and the Politics of Profession." In Lyrical Strains, 35–61. University of North Carolina Press, 2020. http://dx.doi.org/10.5149/northcarolina/9781469659817.003.0002.
Full textAbstract:
This chapter argues that women's writing, specifically poetry in the "Poetess" genre, exposes the tensions that wrack both the ideal liberal and lyric selves. The self-made, autonomous liberal subject was built on a permeable public/private distinction; public circulation confirmed one's circumscribed, and therefore sovereign, interiority. With its expression of private feelings, Poetess poetry was thought to demonstrate the opposite—namely, women's inability to exert liberal self-possession in public and, by extension, their dependent social status and the necessity of confining them to the domestic sphere. In order to illustrate how the literary public sphere enforced these conventions over time, this chapter compares popular texts that rehearse the expectation that women poets were not professional writers but amateurs: they could not help but profess sincere feminine emotion in their poems. In so doing, authors writing Poetess poems could turn amateurism into a kind of public "profession" (both line of work and declaration), and thereby push against the boundaries of belonging that liberalism had set. The chapter explores this process with the example of Frances Sargent Osgood, whose poems specifically about the profession of the Poetess self-consciously expose a feminized interior in public.
10
Müller, Timo. "The Genteel Tradition and the Emergence of the African American Sonnet." In The African American Sonnet, 15–38. University Press of Mississippi, 2018. http://dx.doi.org/10.14325/mississippi/9781496817839.003.0002.
Full textAbstract:
This chapter traces the emergence of the sonnet in African American literature to the pervasive influence of genteel conventions. These conventions have widely been regarded as conservative or even stultifying, but they provided black poets with various opportunities for self-assertion in the public sphere. The sonnet was a favourite genre among the genteel establishment, and poets pushed the boundaries of black expression by appropriating the form to subvert racial stereotypes, develop a black poetic subjectivity, and participate in the debate over the memory of the Civil War. In tracing these developments, the chapter repositions the outstanding poets of the period, Paul Laurence Dunbar and James Weldon Johnson, alongside their less-known contemporaries, Samuel Beadle, William Stanley Braithwaite, Joseph Seamon Cotter Jr., T. Thomas Fortune, and Henrietta Cordelia Ray.
Conference papers on the topic "Pushto Poets"
1
Ng, Kher Hui, Steve Benford, and Boriana Koleva. "PINS push in and POUTS pop out." In CHI '05 extended abstracts. New York, New York, USA: ACM Press, 2005. http://dx.doi.org/10.1145/1056808.1057072.
Full text
2
Al-Shuwaili, Mohammed Abdulhussein, Alessandro Palmeri, and Maria Teresa Lombardo. "A novel one-sided push-out test for shear connectors in composite beams." In 12th international conference on ‘Advances in Steel-Concrete Composite Structures’ - ASCCS 2018. Valencia: Universitat Politècnica València, 2018. http://dx.doi.org/10.4995/asccs2018.2018.7063.
Full textAbstract:
Push-out tests (POTs) have been widely exploited as an alternative to the more expensive full-scale bending tests to characterize the behaviour of shear connections in steel-concrete composite beams. In these tests, two concrete slabs are typically attached to a steel section with the connectors under investigation, which are then subjected to direct shear. The results allow quantifying the relationship between applied load and displacements at the steel-concrete interface. Since this relationship is highly influenced by the boundary conditions of POT samples, different experimental setups have been used, where the slabs are either restricted or free to slide horizontally, as researchers have tried to reduce any discrepancy between POT and full-scale composite beam testing. Based on a critical review of various POT configurations presented in the dedicated literature, this paper presents an efficient one-sided POT (OSPOT) method. While OSPOT and POT specimens are similar, in the proposed OPSPOT setup only one of the two slabs is directly loaded in each test, and the slab is free to move vertically. Thus, two results can be obtained from one specimen, i.e. one from each slab. A series of POTs and OSPOTs have been conducted to investigate the behaviour and the shear resistance of headed stud connectors through the two methods of testing. The results of this study than were compared with those of different POTs setups conducted by other researchers. The new OSPOT results show in general an excellent agreement with the analytical predictions offered by both British and European standards, as well as the estimated shear resistance proposed other researchers in the literature. These findings suggest that the proposed one-sided setup could be used as an efficient and economical option for conducting the POT, as it has the potential not only to double the number of results, but also to simplify the fabrication of the samples, which is important in any large experimental campaign, and to allow testing with limited capacity of the actuator.
3
Martinez Zambrano, Francisco J., Armin K. Silaen, Kelly Tian, Joe Maiolo, and Chenn Zhou. "Reduction of Fuel Utilization Through Oxygen-Enriched Combustion in a Reheat Furnace Pusher-Type." In ASME 2021 Heat Transfer Summer Conference collocated with the ASME 2021 15th International Conference on Energy Sustainability. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/ht2021-63931.
Full textAbstract:
Abstract Steelmaking is an energy-intensive process. Thus, energy efficiency is highly important. Several stages of steelmaking involve combustion processes. One of the most energy-consuming processes in steelmaking is the slab reheating process in a reheat furnace (RF). The energy released by fuel combustion is used to heat steel slabs to their proper hot-rolling temperature. The steel slabs move through the reheat furnace passing the three stages of heating called: Preheating Zone (PZ), Heating Zone (HZ), and Soaking Zone (SZ) to finally leave the discharge door at a rolling temperature of 2375 °F. One way to improve a reheat furnace’s fuel consumption is by implementing oxygen-enriched combustion. This study investigates the implementation of oxygen-enriched combustion in a pusher-type reheat furnace. The increment of oxygen in the combustion process allows for increasing the furnace gas temperature. Consequently, the oxygen enrichment approach allows for the reduction of fuel injection. The principal goal of this investigation is to model the combustion-based on oxygen-enrichment and develop parametric studies of fuel injection rates. The different simulations aim to match the slab heat flux profile of the industrial reheat furnace pusher-type. Computational fluid dynamics are used to generate the slab heat flux distribution. To reach more uniform slab heating, oxygen and fuel ports were alternated. Also, injection angles were modified to optimize slab heating and avoid the impact of hot spots. Thermocouple readings of the industrial reheat furnace are compared to simulation results. The results determined that 40–45% fuel reduction can be achieved.
4
Binns, Jonathan R., Robert Thompson, Paul A. Brandner, and Leonard Imas. "Free-Surface Effects of Variations in Appendage Vertical Volume Distribution: Where does a Bulb not See the Free-Surface?" In SNAME 20th Chesapeake Sailing Yacht Symposium. SNAME, 2011. http://dx.doi.org/10.5957/csys-2011-006.
Full textAbstract:
The vertical distribution of appendage volume for a sailing yacht is predominantly driven by the desire for the lowest possible centre of gravity due to the dependence of sail drive force on stability. This results in volume being pushed downwards regardless of hydrodynamic effects. The increase in aspect ratio of the appendages is also increased with greater draft, resulting in a higher efficiency as well as greater drive force. However, some modern designs have reached the limit of draft in terms of restricted access to ports, structural and rule limitations. To counter these restrictions it is not uncommon to incorporate lifting or swing keels to reduce draft at specified times. The effects on aspect ratio and stability are relatively easy to approximate for such a vertical shift in volume, the effects on the free surface are much more difficult to accurately predict. For this purpose some novel experiments using extreme shifts in vertical volume distribution have been performed and compared with numerical predictions. Limits on submergence beneath which appendages effectively “see” no wave resistance have been established based on numerical and experimental results.
5
San Andre´s, Luis, and Adolfo Delgado. "Identification of Force Coefficients in a Squeeze Film Damper With a Mechanical Seal: Part I — Unidirectional Load Tests." In ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90782.
Full textAbstract:
Squeeze film dampers (SFDs) with low levels of external pressurization and poor end sealing are prone to air entrapment, thus not generating enough damping capability. Single frequency, unidirectional load tests were conducted on a SFD test rig replicating a commercial jet-engine configuration. The damper journal is 2.54 cm in length and 12.7 cm in diameter, with nominal clearance of 0.127 mm. The SFD feed end is flooded with oil, while the discharge end contains a recirculation groove and four orifice ports, and a mechanical seal ring in contact with the damper journal. A wave spring pushes the ring ensuring tight sealing to prevent gas ingestion. The mechanical seal also serves to contain the lubricant within the squeeze film land for extended periods of time and; while in operation, to prevent contamination of the ball bearing cartridge. The measurements conducted without and with lubricant in the squeeze film lands, along with a frequency domain identification procedure, render the mechanical seal dry-friction force and viscous damping force coefficients as functions of frequency and motion amplitude. The end seal arrangement is quite effective in eliminating side leakage and preventing air entrainment into the film lands. Importantly enough, the dry friction force, arising from the contact forces in relative motion, increases significantly the test element equivalent viscous damping coefficients. The identified system damping coefficients are thus frequency and motion amplitude dependent, albeit decreasing rapidly as the motion parameters increase. Identified squeeze film force coefficients, damping and added mass, agree well with predictions based on the full film, short length damper model.
6
Ayers, Jessica A., William C. Tang, and Zhongping Chen. "Paraffin Actuated Micromirror for Endoscopic OCT." In ASME 2009 4th Frontiers in Biomedical Devices Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/biomed2009-83051.
Full textAbstract:
Microelectromechanical systems (MEMS) have great potential for use in gastrointestinal (GI) imaging. Ultrasound and magnetic resonant imaging can provide useful information about the GI tract, but only optical coherence tomography (OCT) delivered endoscopically can be used to perform an optical biopsy of the GI tissue. In monitoring a condition such as Barrett’s esophagus, which typically requires regular random biopsies, the ability to achieve an optical biopsy is indispensible. While the existing method for obtaining an optical biopsy of the GI tract tissue produces functional images, there are drawbacks that could be improved upon. The gear-and-shaft assembly used to couple force from the motor at the proximal end to the distal imaging end requires a complex design [1]. By introducing a rotational MEMS device into the distal imaging end, a rotating optical coupling joint is no longer required at the proximal end, there is no need to precisely align the fixed fiber with the rotational drive shaft, and the metallic reinforcement sleeve can be eliminated leaving a simpler, more flexible delivery method [2]. In order to produce 3D OCT images, displacement in the z-direction needs to be coupled with rotation. A MEMS device that can achieve both vertical displacement and rotation further increases the simplicity of the device and decreases potential alignment and coupling errors. Our MEMS devices needs to be able to bend an OCT beam of light 90°, rotate that beam of light 360°, and simultaneously scan in the z-direction in order to produce 3D OCT images. Also, the device must fit inside the 1 mm diameter available in the endoscope. To accomplish this, we have designed, and are continuing to develop, a paraffin actuated micro mirror. The thermal expansion properties of paraffin wax have often been utilized in MEMS devices [3, 4]. We have made use of these properties in designing a piston like actuator. Heat is applied to a reservoir of paraffin enclosed by a parylene membrane. The paraffin expands and pushes the post above it upward with the developed force from its expansion. The amount of paraffin in each reservoir is controlled by the reservoir’s geometry and so by controlling the amount of heat applied, we can control how far the post above it moves in the vertical direction. Each device has three heaters, three reservoirs, and three posts. All three posts are attached to a single mirror. By appropriately cycling the applied heat to each reservoir, we expect to be able to move the mirror in a spiral like fashion. This will bend an applied beam of light 90° and rotate it 360° while achieving displacement in the z-direction.
7
Cross, Paul E., and Del Baird. "Phased Implementation of In Situ Chemical Oxidation for a Large TCE DNAPL Source Area at the Portsmouth Gaseous Diffusion Plant, USA." In The 11th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2007. http://dx.doi.org/10.1115/icem2007-7200.
Full textAbstract:
This paper describes the In Situ Chemical Oxidation (ISCO) remediation being implemented for the X-701B groundwater plume at the Department of Energy (DOE) Portsmouth Gaseous Diffusion Plant (PORTS). Modified Fenton’s reagent is the principal oxidant for the remedy, and Direct Push Technology (DPT) is being used for delivery of the oxidant. Trichloroethene (TCE) is the primary contaminant of concern and is present within the unit as a dense non-aqueous phase liquid (DNAPL). A phased approach is being implemented to optimize the type, location, and mass of the oxidant injections. During Phase I, a unique near-real time monitoring approach was utilized to observe the transient effects of the oxidant injections on the formation. As a result of the positive results from Phase I, Ohio EPA has approved the final work plan for the remedy, and the approach is now being applied to the source area of the plume. The results from Phase I and the layout for the first series of Phase II injections are presented in this paper. Previous testing at the site has shown that the shallow, water-bearing formation is primarily composed of silty gravel and clay, and is both heterogeneous and anisotropic. These factors have significantly compromised earlier attempts to remediate the unit. A patented ISCO process from In-Situ Oxidative Technologies, Inc. (ISOTEC) was selected for the remediation of the plume. Phase I results indicate that oxidant delivery via DPT is feasible for the unit. Contaminant reduction to date has been minimal due to the small quantity of oxidant injected during Phase I. Contaminant rebound in the aqueous phase remains a concern and will be monitored closely during the remedy.
8
KC, Pratik, Sangeet Shrestha, Adarsh Radadia, Leland Weiss, and Arden Moore. "Design and Performance of Novel Low-Profile Heat Sinks Created Through Additive Manufacturing." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66320.
Full textAbstract:
Traditional thermal management techniques such as air-cooled plate- and pin-fin heat sinks are today being pushed to their limits by the increasing power densities of computing hardware (power supplies, controllers, processors, and integrated circuits). In comparison, direct immersion cooling within an alternative cooling medium such as commercial dielectric fluids offers the ability to handle high power densities while also accommodating tighter printed circuit board spacing. Together, these attributes are critical to facilitating higher computing densities. However, this type of high density setup also requires that any heat sink present be low profile so as to not obstruct adjacent printed circuit boards. Such a stringent limit on heat sink height can make achieving cooling targets challenging with existing designs. In this work, the performance of several low profile (height less than 6 mm) heat sinks of varying design are evaluated within a carefully controlled direct immersion cooling environment. Commercial copper heat sinks fabricated through conventional manufacturing (CM) approaches serve as baselines for these performance tests. These same heat sink designs are also replicated via additive manufacturing (AM) utilizing a conductive, carbon-filled printable polylactic acid (PLA) composite material. The performance of these AM heat sinks are then compared to the CM heat sinks, with special emphasis on differences in thermal conductivity between the constituent materials. Finally, novel bio-inspired heat sink designs are developed which would be difficult or impossible to achieve using CM approaches. The most promising of these designs were then created using AM and their performance evaluated for comparison. The overall goal of this is to ascertain whether the design and fabrication flexibility offered by AM can facilitate low profile heat sink designs that can meet or exceed the performance of conventional heat sinks even with perceived deficiencies in material properties for AM parts. Experiments were carried out within Novec 7100 dielectric fluid for single-phase natural convection scenarios as well as two-phase subcooled boiling conditions at atmospheric pressure. A custom test rig was constructed consisting of mirror-polished stainless steel plates and polycarbonate viewing ports to allow visual access. A rotating sample stage allows for data to be obtained at varying heat sink orientation angles from 0° to 90°. For two-phase experiments, multi-angle video capture allows for analysis of the two-phase dynamics occurring at the heat sink samples to be visualized and temporally linked to the associated temperature and heat flux data.
9
Thyagarajan, Ashok, Vijay Dhir, and Debjyoti Banerjee. "Experimental Investigation of Solar-Thermal Desalination Platform Leveraging Dynamic Flash Evaporation and Swirl Flow Separator." In ASME 2022 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/imece2022-96099.
Full textAbstract:
Abstract Commercial thermal desalination plants usually leverage static flash evaporation and vapor separation processes that occur separately in large chambers. Depending on the level of purity — the product can be used for potable water (for human consumption), for agriculture or ranching, or as input for industrial processes (such as in injection wells in oil and gas production operations). Currently, static methods such as Multi Stage Flash (MSF) or Multi Effect Distillation (MED) are widely used (in addition to Reverse Osmosis) for desalination. These static methods occupy large land area (large footprint). This in turn drives up the capital and production costs of the resulting purified water obtained in these techniques. Desalination processes that leverage evaporation and vapor separation in the same chamber (dynamically) have smaller form factors which confers lower cost of desalination. Thus, the motivation of our study is to develop a novel apparatus to simultaneously generate vapor by flash evaporation and separate the produced vapor in the same apparatus. The novel apparatus is geared for desalination of sea water, remediation of produced water from process-industries and other sources of saline water (such as brackish water) that are deemed unfit for human consumption. The end goal of the project is to develop a solar-thermal desalination platform by leveraging hot saline water as input from solar ponds. In this experimental study, the thermal-hydraulic performance of a prototype (lab-scale) dynamic vapor generation and swirl flow phase separation apparatus is explored for determining the efficacy of this novel concept. Heated water from a constant temperature supply tank (that is comparable to a solar pond in real life) is passed through injection passages into the flow-separation apparatus. As the water flows through the injection passages, vapor bubbles are generated inside the flow passages due to local superheating of the liquid caused by frictional pressure drop. Conversion of liquid into vapor continues as the liquid-vapor mixture flows through the injector ports and eventually the mixture enters a larger separation tube tangentially. Due to the tangential injection of the two-phase mixture, a centrifugal force acts to separate the water and vapor inside the separation tube. The liquid is pushed to the periphery (i.e., the walls) of the separation tube while the vapor forms a stable core at the center. A vapor retrieval tube is then positioned at the center of the vapor core to extract vapor which is then condensed inside the condenser. The formation of the vapor core is demonstrated for different operating conditions (supply liquid flow rates) and maximum superheat (temperature difference between supply tank and condenser) ranging between 45–52°C. Based on this study, the optimal operating conditions for maximizing the thermal conversion upstream of the test section are presented.
10
Abd Hamid, M., Z. Awang @ Mohamed, A. Zeidan, N. Nazkuliyev, Y. Tan, and B. Bahar. "Real Time Gaslift Optimization: Lessons from Field Implementation of Smart Completions for Future Redevelopment Projects Offshore Peninsular Malaysia." In International Petroleum Technology Conference. IPTC, 2024. http://dx.doi.org/10.2523/iptc-24246-ea.
Full textAbstract:
Abstract "G" field is a mature field that has been producing for 30 years from 4 platforms. 90% of the wells are on gaslift. Well integrity issues including tubing leaks are common because of corrosion on account of contaminants (CO2 60% and H2S 10 to 100 ppm) and erosion due to sand production. These problems are observed particularly in older wells, which were completed without corrosion resistant tubulars and any downhole sand control. Optimizing gaslift for hundreds of wells is challenging due to robbing effect in dual-string wells, months of lead time to secure slickline for gaslift valve change (GLVC) or to conduct pre-GLVC pressure surveys. In some cases, sand cleanout must be performed before well intervention which delays GLVC opportunities to increase production. In a recent drilling campaign, a smart gaslift completions system "D" was installed in one single-string well (G1) and one dual-string well (short-string G2-SS and long-string G2-LS) to overcome the challenges described earlier. This paper presents valuable lessons learned over a two-year period since these wells were completed. D system has variable injection orifice ports downhole which are electronically operated through a cable using a Surface Control System (SCS). Each production string can be installed with several orifice units at designed depths, with each unit having pressure and temperature sensors linked to PI system for remote monitoring. Gaslift configuration changes can then be implemented anytime by "push-of-a-button" without well intervention. In comparison, conventional gaslift valves must be configured at the onshore workshop to operate under specific injection or production pressures at downhole temperatures, and then transported offshore to replace existing valves via slickline; and this excludes time needed for downhole data acquisition, analysis and GLVC design. The technology provided live downhole static/ flowing data that allowed the valves to be configured for unloading both the wells and enabled incremental adjustments to deepen gaslift injection while the wells were flowing. This ensures single-point injection (no multi-pointing) and eliminates separate shut-in intervention for pressure surveys or GLVC. Installing D system, which is run as part of completion tubing, removes slickline intervention limitations in high-angle wells. One extra benefit specific to G1 well was that live D system data was used to confirm both surface pumping data and the effectiveness of post-completion acid stimulation carried out via bull-heading. Backup gaslift mandrels are recommended to mitigate the risk of cable damage associated with running the system in high-angle, dual-string wells. In future, for similar well types, this technology should be implemented with care and by considering spacing of well accessories on both strings. The upfront cost of D system is higher than a conventional gaslift, but its justification is in reduced operating cost over well life, which comes from eliminating slickline pressure surveys and GLVC (while reducing deferred production), as well as any delay in routine optimization through GLVC.