Dissertations / Theses on the topic 'Surface sealing'
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Raja, Mohan Anandu, and Niranjan Sutar. "Characterization of Sealing Surface for Static Seals." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-263915.
Full textLäckagerisk från tätande förband är en av de viktigaste faktorerna som beaktas vid utformning av konstruktionsartiklar. Detta på grund av att konsekvenserna kan bli förödande. Det tätande förbandet påverkas av många olika parametrar såsom till exempel tryck, temperatur, klämkraft, skruvavstånd och val av packning. En viktig faktor är ytans beskaffenhet; Generellt läcker en grov yta och vågig yta mer än en fin och plan yta. Således har i denna avhandling ytans beskaffenhet studerats tillsammans med en packning av typen metallburen gummipackning för att påvisa täthetfunktionen som en funktion av tryck, temperatur, klämkraft och skruvavstånd. Denna rapport innehåller resultat och analys av olika standardmetoder för de ytor som ingick i utredningen.
Geeves, Guy William, and not available. "Aggregate Breakdown and Soil Surface Sealing under Rainfall." The Australian National University, 1997. http://thesis.anu.edu.au./public/adt-ANU20010702.142014.
Full textHawke, Richard Michael. "The energetics and dynamics of surface sealing, a laboratory investigation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ28280.pdf.
Full textNeumann, Stephan, Georg Jacobs, Achim Feldermann, and Felix Straßburger. "Reducing Friction and Leakage by Means of Microstructured Sealing Surfaces – Example Mechanical Face Seal." Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-199867.
Full textBlomlöf, Johan. "Root surface conditioning in periodontal treatment /." Stockholm, 1997. http://diss.kib.ki.se/1997/91-628-2646-8.
Full textBonsu, Mensah. "Structural stability and surface sealing as related to organic matter depletion of a shallow organic soil." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26961.
Full textLand and Food Systems, Faculty of
Graduate
Jones, Gordon A. "Tribology of the mechanical sealing interface : an evaluation of the role and potential of surface engineering." Thesis, University of Salford, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.300829.
Full textJones, Trevor. "Fracture Sealing by Mineral Precipitation| The Role of Surface Heterogeneities on Precipitation-Induced Transport Property Alterations." Thesis, University of California, Irvine, 2019. http://pqdtopen.proquest.com/#viewpdf?dispub=13424490.
Full textFractures are often leakage pathways for fluids through low-permeability rocks that otherwise act as geologic barriers to flow. Flow of fluids that are in chemical disequilibrium with the host rock can lead to mineral precipitation, which reduces fracture permeability. When fracture surfaces contain a single mineral phase, mineral precipitation leads to fast permeability reduction and fracture sealing. However, the feedback between precipitation and permeability may be disrupted by mineral heterogeneities that localize precipitation reactions and provide paths of low-reactivity for fluids to persist over relatively long time-scales. In this dissertation, I explore the role of mineral heterogeneity on precipitation-induced permeability reduction in fractures. To do this, I use a combined experimental and numerical approach to test three hypotheses: (1) Mineral heterogeneity prolongs fracture sealing by focusing flow into paths with limited reactive surface area, (2) Precipitation-induced transport alterations at the fracture-scale are controlled by three-dimensional growth dynamics at the grain-scale, and (3) The effects of mineral heterogeneity become more pronounced as mineralogy and surface roughness become autocorrelated over similar length-scales.
Direct measurements of mineral precipitation using transmitted light methods in a transparent analog fracture show that mineral heterogeneity can lead to the progressive focusing of flow into paths with limited reactive surface area, which is in support of (1). In this experiment, flow focusing led to a 72% reduction in the max precipitation rate; measurements of the projected mineralogy show that this was due to focusing of large dissolved ion concentrations into regions that contained 82% less reactive surface area than the fracture-scale average. Results from a newly developed reactive transport model that simulates precipitation-induced fracture surface alterations as a three-dimensional process are in good qualitative agreement with these experimental observations. Comparison of these results with a reactive transport model that represents precipitation as a 1D alteration of the fracture surfaces show that this flow-focusing process is driven by lateral growth of reactive minerals across the fracture-plane, which supports (2). Lastly, results from simulations in fractures that contain varied degrees of heterogeneity show that precipitation leads to a competition between two feedbacks: (i) precipitation-induced reactive surface area enhancement, which increases precipitation rates, and (ii) precipitation-induced permeability reduction, which decreases precipitation rates. When surface roughness and mineral heterogeneity provide persistent paths of limited surface area, the reactive transport becomes very sensitive to local permeability reduction. Simulation results show that this prolongs the fracture-sealing process and can lead to a reduction in fracture-scale precipitation rate, which supports (3). Furthermore, the results presented in this dissertation demonstrate that predictions of fracture sealing by mineral precipitation can be easily misinformed by studies that ignore small-scale mineral heterogeneity and neglect the three-dimensional nature of precipitation-induced fracture surface alterations.
OLIVEIRA, FELIPE de. "Estudo de camadas finas tratadas por laser em anéis de pistão." reponame:Repositório Institucional do IPEN, 2011. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10048.
Full textMade available in DSpace on 2014-10-09T14:06:38Z (GMT). No. of bitstreams: 0
Dissertação (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
Tafoya, Keirsten Breann. "Process Improvement of Surface Preparation of Structuraly Bonded Helicopter Detail Parts." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1404599/.
Full textBalfour, Victoria Nairn. "The effect of forest fires on runoff rates the role of duff removal and surface sealing by vegetative ash, western Montana /." Diss., [Missoula, Mont.] : The University of Montana, 2007. http://etd.lib.umt.edu/theses/available/etd-12202007-181528/.
Full textBerggren, Anton, and Tobias Grahn. "Undersökning av tätningsmetoder med fokus på aluminiumhus." Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-12639.
Full textIn this work sealing methods for aluminum housing have been investigated. The work was delimited to the automotive industry and static gaskets. The thesis brings up how the flange impacts on the sealing capability and the gasket, sealing types, the surface impact on gasket materials, porosity, relative material cost and fasteners.The work is based on a literature study and interviews with concerned people at the company. Practical samples were carried out on a number of materials from suppliers and the materials where exposed to different chemicals and then tensile tested.The materials that were collected through interviews and the literature study testify that many parameters influence the possible sealing methods. It’s not just the material itself that needs to be taken into account. Factors like flange design, material cost, surface defects, fasteners and porosity have a great impact. The practical sample testifies that different chemicals have dif-ferent impact on the mechanical properties and swelling of the material.Finally, a couple of sealing materials are suggested that are suitable for the company to use in their products.
Soares, Tatiane Aparecida. "Rodas compactadoras e aterradoras na qualidade de acabamento de semeadura direta /." Jaboticabal : [s.n.], 2009. http://hdl.handle.net/11449/100852.
Full textAbstract: No-till is a system of conservation management of agricultural production, which promotes the improvement of the physical, chemical and biological soil conditions. Thus, the purpose of this study was to evaluate the systems finish seeding on the market in Brazil, used in precision seeders for no-till planters, as well as new proposals, considering factors that affect seed germination and emergence seedlings in the field. The experiment was conducted at the Experimental Farm of the Agronomic Institute of Paraná - IAPAR, in Londrina, using the randomized block planning with eight treatments and four repetitions for the cultivation of beans and three repetitions for soybean. Treatments consist of eight systems of finish seeding that having components with and without ground finish systems, depth of seed and compactor wheels. Was evaluated soil variables, seeds variables and performance parameters of seeding units. It was concluded that soil cover disks improve the seeding units performance, benefit the operation in different aspects and increasing the emergency. Parallel depth controller wheels improve results of soil cover discs, including the emergency. The flat compactor wheels are not recommended, because they promote soil surface sealing problems. The wheels in "V" had good results, but the wheels with grip and internal ridges tend to be better
Orientador: Carlos Eduardo Angeli Furlani
Coorientador: Ruy Casão Júnior
Banca: Rouverson Pereira da Silva
Banca: Antonio Sérgio Ferraudo
Banca: Luiz Malcolm Mano de Mello
Banca: Wilson José Oliveira de Souza
Doutor
Chen, Qing-Li. "Effect of surface topography on hip prosthesis anchorage." Thesis, Queensland University of Technology, 1997.
Find full textSoares, Tatiane Aparecida [UNESP]. "Rodas compactadoras e aterradoras na qualidade de acabamento de semeadura direta." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/100852.
Full textCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O plantio direto consiste em um sistema de manejo conservacionista da produção agrícola, que promove a melhoria das condições físicas, químicas e biológicas do solo. Desta forma, o objetivo do presente trabalho foi a avaliação de sistemas de acabamento de semeadura existentes no mercado nacional, utilizados em semeadoras de precisão para plantio direto, assim como novas propostas, levando em conta fatores que afetam a germinação das sementes e a emergência das plântulas no campo. O experimento foi conduzido na Fazenda Experimental do Instituto Agronômico do Paraná – IAPAR, em Londrina, utilizando-se o delineamento experimental em blocos ao acaso, com oito tratamentos e quatro repetições para a cultura do feijão e três repetições para a cultura da soja. Os tratamentos foram constituídos de oito sistemas de acabamento de semeadura, dotados de componentes com e sem aterramento, sistemas de controle de profundidade de sementes e rodas compactadoras. Foram avaliadas variáveis do solo, das sementes e parâmetros de desempenho das unidades semeadoras. Conclui-se que os discos aterradores melhoram os resultados das unidades de semeadura, beneficiando a operação em diferentes aspectos e aumentando a emergência. As rodas controladoras de profundidade paralelas melhoram os resultados dos discos aterradores, inclusive os de emergência. As rodas compactadoras lisas não são indicadas, pois promovem problemas de selamento superficial. As rodas compactadoras em “V” apresentaram bons resultados, mas as rodas compactadoras com garras e sulcos internos tendem a ser melhores
No-till is a system of conservation management of agricultural production, which promotes the improvement of the physical, chemical and biological soil conditions. Thus, the purpose of this study was to evaluate the systems finish seeding on the market in Brazil, used in precision seeders for no-till planters, as well as new proposals, considering factors that affect seed germination and emergence seedlings in the field. The experiment was conducted at the Experimental Farm of the Agronomic Institute of Paraná – IAPAR, in Londrina, using the randomized block planning with eight treatments and four repetitions for the cultivation of beans and three repetitions for soybean. Treatments consist of eight systems of finish seeding that having components with and without ground finish systems, depth of seed and compactor wheels. Was evaluated soil variables, seeds variables and performance parameters of seeding units. It was concluded that soil cover disks improve the seeding units performance, benefit the operation in different aspects and increasing the emergency. Parallel depth controller wheels improve results of soil cover discs, including the emergency. The flat compactor wheels are not recommended, because they promote soil surface sealing problems. The wheels in V had good results, but the wheels with grip and internal ridges tend to be better
Ахмедова, Т. Є. "Удосконалення технології ремонту верхнього блоку та головного циркуляційного трубопроводу реактора (комплексний)." Thesis, Чернігів, 2020. http://ir.stu.cn.ua/123456789/23099.
Full textМета роботи – розробити технологію ремонту ущільнюючої поверхні головного роз’єму реактора, таку що може гарантувати повне відновлення ущільнюючої поверхні проектних розмірах. Відповідно до поставленого завдання проведено аналіз технологічності пристосування, розроблено технологічний процес для ремонту ущільнюючої поверхні головного роз’єму реактора, спроектовано і обрано основне зварювальне обладнання та обладнання для механічної обробки поверхні для досягнення підвищення продуктивності. Випускна робота виконана в текстовому редакторі Microsoft Word 2010 та графічному редакторі «КОМПАС – 3D V18.1».
The purpose of the work is to develop a technology for repairing the sealing surface of the main reactor connector, which can guarantee the complete restoration of the sealing surface of the design dimensions. In accordance with the task, an analysis of the adaptability was made, a technological process for repairing the sealing surface of the main reactor connector was designed, and the main welding equipment and equipment for machining the surface to produce increased productivity were designed and selected. The final work made in Microsoft Word 2010 word processor and the graphical editor "KOMPAS - 3D V18.1".
Green, Christopher K. "Development of Model for Solid Oxide Fuel Cell Compressive Seals." Diss., Georgia Institute of Technology, 2007. http://hdl.handle.net/1853/19696.
Full textChahboun, Najat. "Compréhension des mécanismes de colmatage des couches anodisées sur alliages d’aluminium aéronautiques et développement de nouvelles formulations de colmatage." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0318.
Full textAluminium alloys are very used in the aircraft industry as structural materials because of their low density and their good mechanical properties. They have a polyphase microstructure that is causing electrochemical discontinuities and increasing sensitivity to corrosion. A system of protective coatings containing chromate Cr(+VI) is traditionally formed at the surface of these alloys. However, the REACH environmental guidelines impose Cr(+VI) surface treatments replacement because of chromate carcinogenicity. The aim of the thesis work has been the development of a new surface treatment constituted of a sulfuric acid anodizing (SAA) and a sulfate chromium and fluorozirconate salts sealing (Cr3+/ ZrF62-). The study of the SAA electrochemical process linked the alloys microstructure and the anodic layer porous morphology developed at their surface. The Cr3+ / ZrF62- sealing treatment is realized by a simple immersion of the anodized alloy in the solution. It is demonstrated that the sealing is caused by a local alkalinization of the anodized coating surface that leads to the precipitation of the Cr3+ and ZrF62- salts. These ones are forming a sealing film of about 300 nm thick, very covering of the nanometric pores. The anodic layers sealing greatly improves the corrosion resistance of the anodized alloys by forming an additional barrier against corrosive agents and by healing the corrosion initiation. The developed treatment allows both to achieve Cr(+VI) treatments performance over a wide range of alloys and to satisfy the environmental requirements
Sedláček, Tomáš. "Konstrukční úprava upínaní tlakových zásobníků vstřikovacího systému Common Rail při výrobě." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2014. http://www.nusl.cz/ntk/nusl-231328.
Full textBobe, Bedadi Woreka. "Evaluation of soil erosion in the Harerge region of Ethiopia using soil loss models, rainfall simulation and field trials." Thesis, University of Pretoria, 2004. http://hdl.handle.net/2263/26929.
Full textThesis (PhD (Soil Science))--University of Pretoria, 2004.
Plant Production and Soil Science
unrestricted
Sultan, Abdullah Emad. "Alternative Methods for Sealing Overlapping Steel Members with Narrow Gaps During Galvanizing." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83182.
Full textMaster of Science
Pagliuca, Antonio. "Adhesion and material properties of construction sealants." Thesis, Oxford Brookes University, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.261492.
Full textGoussakov, Alex, and Alin Dumitru Durac. "Tribological characterisation of turbocharger turbine sealing rings in heavy duty diesel engines." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-67300.
Full textNahsan, Flávia Pardo Salata. "Influência da aplicação de selantes de superfície na rugosidade de resinas compostas." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/25/25131/tde-28052009-165339/.
Full textThis in vitro study evaluated the influence of the application of four surface sealers on the surface roughness of composite resins. Fifty specimens were divided into ten groups according to different patterns of composite resin and surface sealers, as follows: G1. Control with Concept resin; G2. Concept + Fortify; G3. Concept + Biscover; G4. Concept + Lasting Touch; G5. Concept + Fill Glaze; G6. Control with Esthet X; G7. Esthet X + Fortify; G8. Esthet X + Biscover; G9. Esthet X + Lasting Touch; G10. Esthet X + Fill Glaze. Specimens were made in four increments using a stainless steel matrix of 15x5x4mm and resin increments were polymerized with halogen lamp Curing Light 2500 (500mW/cm2) for 20 seconds each. After complete polymerization, specimens were stored in 100% humidity in distilled water at 37ºC for 24 hours. Following storage, specimens were polished using ascending grades (320, 600) of abrasive SiC paper under running water and the initial roughness was measured with a perfilometer Hommel Tester T100 basic (Hommelwerke GmbH ref. # 240851 - Schwenningem - Germany). Surface sealers were applied following the manufacturer\'s instructions and a new measurement of roughness was made. For the abrasive resistance test, specimens were submitted to 100.000 cycles of abrasive dentifrice brushing followed by surface roughness.. Qualitative analisys was made by using MEV. Results were submitted to Three-way ANOVA (p<0,05) and Tuckey\'s test to individual comparisons between different groups. Surface sealant application provided smoother surfaces for of composite resins tested (G2=0.0727, G3=0.0147, G4=0.0307, G5=0.0253, G6=0.0960, G7=0.0173, G8=0.0333, G9=0.0480). The abrasion test increased the surface roughness for all tested groups, except Fortify (G2=0,0740, G7=0,0673) and Biscover (G7=0,0440). Lasting Touch presented rougher surfaces (G4= 0,1253, G9=0,0980), followed by Fill Glaze (G5=0,0933, G10= 0,0847).
Nahsan, Flavia Pardo Salata, Linda Wang, Karin Silva Modena, Dos Rios Luciana Fàvaro Francisconi, Luciana Mendonça da Silva, Marcela Pagani Calabria, Leslie Casas-Apayco, and Rafael Francisco Lia Mondelli. "A 12-month clinical trial examining the effects of a surface sealant on Class I composite resin restorations." Chicago, Academy of General Dentistry, 2016. http://hdl.handle.net/10757/607232.
Full textA split-mouth, double-blind trial evaluated the effects of a surface sealant on the clinical performance of Class I composite resin restorations. In 16 patients, 27 pairs of maxillary and mandibular molars or premolars with Class I carious lesions or unsatisfactory restorations were restored with composite resin. For each pair, 1 surface was sealed with surface sealant. Clinical evaluations of marginal integrity, marginal discoloration, anatomical form, and secondary caries were performed by 2 experienced operators using modified US Public Health Service criteria 1-2 weeks and 6 and 12 months after treatment. Data were analyzed with the McNemar test (P < 0.05). After 6 months, only 1 (4%) sealed restoration presented a Bravo rating for marginal integrity. After 12 months, the Bravo ratings for marginal integrity were 2 (7%) for sealed restorations and 1 (4%) for nonsealed restorations. Restorations received a score of Alfa for all other parameters at all time periods. There were no statistically significant differences within or between the sealed and nonsealed groups (P = 1.0). The use of a surface sealant did not improve the clinical performance of posterior composite resin Class I restorations.
Revisión por pares
Nahsan, Flávia Pardo Salata. "Avaliação da influência da aplicação de um selante de superfície no comportamento clínico de restaurações de resina composta classe I." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/25/25148/tde-05112012-181419/.
Full textThe finishing, polishing and surface sealant application, by superficial irregular penetration and between restoration interface, are applied at the end of the restoration and decrease these limitations, and extend the clinical longevity of composite resin restorations. This clinical randomized controled study however aimed to evaluate the effect of the surface sealant application in the clinical behavior of composite posterior resin class I restorations. Twenty seven pairs of upper or lower molars or premolars with carious lesions (class I), and unsatisfactory amalgam or composite resin restorations, which needed total replacement, were randomized and prepared and restored with Esthet X composite resin. The composite resin surface of one tooth from each pair was covered with Lasting Touch surface sealant (Split Mouth Design). The clinical evaluation was made by using the modified direct method USPHS, at the following times: baseline, 6 months and 12 months, by two different operators. Bitewing radiographs and replicas of the occlusal surfaces were obtained by using a silicone impression material poured with epoxy resin for the qualitative evaluation with Scanning Electron Microscopy. The data was analyzed with the McNemar test (p <0.05). Results showed that for the marginal integrity, after 6-month evaluation, only 1 (4%) sealed restoration had a Bravo rating. At the end of 12 months, the marginal integrity showed 1 (4%) sealed restoration and 2 (7%) non sealed Bravo restorations. Results at all evaluations periods did not show statistical significant differences (p=1.0) for all conditions. There was no difference in the clinical performance of the composite resin restorations (Esthet X) with or without the surface sealant (Lasting Touch), demonstrated good behavior after 12 months. Based on SEM examinations, the surface sealant application promoted a regular and smooth surface, for all the evaluation times. In a 12 months evaluations period, the surface sealant demonstrated stability at the evaluated condition. The SEM, however, did not presented better conditions in the no sealant application group (control).
CONCIALDI, Paola. "INVESTIGATIONS ON INFILTRATION METHODS FOR AN IMPROVED SOIL HYDRAULIC CHARACTERIZATION." Doctoral thesis, Università degli Studi di Palermo, 2020. http://hdl.handle.net/10447/440688.
Full textCruz, Carlos Alberto dos Santos. "Estudo da dureza e da resistência à compressão de resinas compostas para dentes posteriores após a imersão em água destilada. Efeito da aplicação de selante superficial /." Araraquara : [s.n.], 2001. http://hdl.handle.net/11449/116093.
Full textAbstract: New materials have been specifically indicated to direct posterior esthetic restoration. Although the clinical results seem to be satisfactory, at first, they haven't been enough to warrant restoration longevity. Posterior composite resins are subjected to compressive and abrasive stresses and surface penetrating sealants have been indicated in order to increase resins' wear resistance. The aim of this study was to evaluate hardness and compressive strength of posterior composite resins (Alert/Jeneric-Pentron, Ariston/Vivadent, Definite/Degussa, P60/3M, Solitarie/Kulzer, Surefil/Dentsply and Z100/3M), treated with a surface sealant (Protect It/Jeneric-Pentron), after 90 days of destiled water immersion and subjected at 10,000 stress cycles (600N, 5Hz). The hardness tests (n=8) were conducted on Wolpert equipment, using a Wickers diamond and 50gf load applied for 30 seconds before and after immersion for 30, 60 and 90 days. The compressive tests (n=8) were conducted after 90 days on MTS-810 machine with load cell of 10kN (cycling) and 100kN (compressive strength) and crosshead speed of 0.5 mm/min in samples 4mm of diameter and 8mm height. Before immersion (Anova, p<0,05), Z100 (74.253VHN) and Ariston (71.308VHN) showed the highest hardness. Surefil (69.969VHN) was similar to Ariston, but significantly lower than Z100. Alert (66.138VHN) was lower than Surefil, but higher than P60 (62.833VHN) and Definite (61.302VHN). Solitaire (46.609VHN) exhibited the lower hardness. After immersion, there was a significant decrease in hardness for almost all materials (Ariston, 97%; Definite, Solitaire and Surefil, 26%; Z100, 12% and Alert, 8%). Surface penetrating sealant had no effect on hardness values. Without cyclic loading (Anova, p<0,05), Z100 (336.275MPa), Alert (334.350MPa), P60 (331.000MPa)... (Complete abstract, click electronic access below)
Garcia, Lourdes Maria González. "Efeito in situ do clareamento caseiro e subseqüentes tratamentos de superfície na cor e rugosidade superficial de resinas compostas." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/58/58131/tde-22052012-110850/.
Full textThis study evaluated in situ the staining susceptibility of different composite resins (Z350 XT ® (M1) and Z250 ® (M2), both of 3M/ESPE) by color change and surface roughness after the aplication of 16% carbamide peroxide bleaching gel and subsequent surface treatments and staining with red wine. One hundred fifty-six specimens were fabricated where n=13 were per experimental condition. The study had two phases of 14 days each, with a washout period of 9 days between them. The specimens of each material fixed into custom fabricated trays in 13 volunteers in the region of the second premolars, first and second molars and installed in the participants to carry out for the proposed treatment at each stage. According randomly 6 volunteers used in the first stage of the experiment the 16% peroxide carbamide gel (Home Peroxide, DMC) (CCL) and 7 volunteers used placebo gel (DMC) (SCL) that it was the same composition original gel, but without addition of peroxide. The volunteers applied the gel on the top of the specimens for 8h/day for 14 days during the two phases of the experiment. After bleaching treatment the specimens were subjected to the following surface treatments: polishing with Sof Lex (3M/ESPE) (TR1), without surface treatment (TR2) and the application of the sealant surface Biscover (BISCO) (TR3) and subsequently were immersed in red wine. In the second phase of the experiment, the specimens were replaced by others and the volunteers were crossed on the gel, so that all used both gels. Finishing the second phase, the specimens were subjected to surface treatment and subsequent staining. The color change were measured 24 hours after bleaching in situ (L0) and 24 hours after surface treatment and red wine stains (L1) and the surface roughness were measured immediately after 24 hours of preparation of the specimens (L0) 24 hours after the in situ bleaching treatment (L1) and 24 hours after surface treatment and staining with red wine (L2). Data were submitted to ANOVA and Tukey. The results showed that: a) The bleaching showed no statistically significant difference for ΔE *, however, was significant for all parameters ΔL*, Δa* and Δb*; b) The composite 350 XT presented higher average of color change (ΔE * ) than Z250; c) The surface treatments with Sof Lex and Biscover had values of ΔE* statistically similar, while no treatment surface showed a statistically significant difference between the materials; d) Bleaching had no significant effect on surface roughness of composite resins; e) The composites showed higher values of surface roughness in L2 than in L1 and L0. f) TR3 demonstrated higher average of surface roughness than TR1 and TR2. It was concluded that bleaching did not affect the color change and surface roughness in the composites studied, the surface treatment had no effect clinically significant for the susceptibility to staining, and the composites studied had higher surface roughness when subjected to treatment surface staining associated with red wine and the surface sealant Biscover showed higher surface roughness for resin Z250.
Chen, Chung-Han, and 陳忠漢. "Sealing Method On Micro-Arc Oxidation Ceramic Surface." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/21618407389621415632.
Full text龍華科技大學
工程技術研究所
101
This study proposes the optimal parameters for micro-arc oxidation method with various sealing techniques in order to improve the isolation of the LED ceramic substrate. The results of this technique can be applied to the ceramic printed circuit boards, the sealing of biomedical porous material, the traditional precision machinery manufacturing, and for 3C product surface treatment. In this study, with a different set of micro-arc oxidation voltage, we use the optimal conditions for sealing treatment including high-temperature heating method、screen printing method、spray method、impregnation method, and chose the better sealing means based on the experimental results in order to enhance yield rate. The micro-arc oxidation results showed that: better micro-arc oxidation film thickness, dielectric strength and adhesion can be obtained under the voltage of 575V. Various sealing treatment methods showed: the micro-arc oxidation spray method has better adhesion and insulation in addition to without holes for the surface morphology.
Geeves, Guy William. "Aggregate Breakdown and Soil Surface Sealing under Rainfall." Phd thesis, 1997. http://hdl.handle.net/1885/47081.
Full textYu-Chiao and 沈玉嬌. "Sealing and Peeling Test Gauge R&R Nested Study for Surface Mount Supplies Process." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/24078963557751093962.
Full text萬能科技大學
經營管理研究所
97
Quality is the foundation of any company to survive in a competitive market. No matter how simple a product is, quality cannot be neglected. In the past, many evaluation of quality were carried out by human judgments. Therefore, it makes quantification of quality evaluation difficult. Furthermore, it makes it impossible to prove an evaluation system adequate for a specific product quality level. This study is based on a real product functional inspection development. It includes customer application simulation, preliminary product functional evaluation, a Measurement System Analysis (MSA) for the interested product function combined with designed experiments, presentation of experiment results by MINITAB, and discussion of future improvement. US auto industries have been advocating QS9000, which was updated to TS16949 of these years, for many years, as a component of that quality assurance system, MSA has drawn great attention. It has been a new trend that quality evaluation and decision making are based on quantified measurement.
YEN, Chia-Yi, and 顏嘉誼. "Investigation of Cyclic Block/Olefin Copolymer Microchannel Sealing by Thermal Bonding, Surface Modification and Solvent Treatment." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/8643rb.
Full text國立中央大學
機械工程學系
105
Cyclic block copolymer (CBC) is a new class of thermoplastic with excellent optical property, low water absorption, great chemical resistant and low density. It is also suitable for injection molding, injection blow molding and embossing fabrication process. In order to know the CBC suitability of microfluidic chip, the microchannel sealing quality of microfluidic chip used CBC as substrate material was studied for a functional microchannel chip shows no leakage after microchannel sealing is necessary. This thesis used two grade of cyclic block copolymers (CBC010&CBC034) as main study objects. Cyclic olefin copolymers (COC) and cyclic olefin polymers (COP) were used as microchannel sealing quality comparison group for they have been commonly used in microfluidic chip fabrication. Three bonding methods were used in this study which are: pure thermal bonding, thermal bonding after UV/ozone surface modification and solvent bonding. For solvent bonding, spin coating method was applied for distributing solvents (toluene, n-hexane, methyl cyclohexane) on thermoplastic substrates instead of vaporing and dropping method to efficiently form a uniform and few bubble bonding interface. The experiment results show that CBC010 has extra-high transparency and its high melt flow rate causing 30% channel deformation after pure thermal bonding.(Original channel height/width:124/200µm). After surface treatment, CBC034 showed highest bonding strength and only 5.68µm channel deformation after thermal bonding, the channel deformation of CBC010 also decreased to 5.86µm, both their deformation percentage were lower than 5%. COC and COP microchannel were successfully sealed with three solvents and no clogging and collapse happened. CBC series showed their high solvent resistance that hardly be solvated by solvents that surface didn’t become soft and mobile after solvent treatment.
Jui-chun, Liu, and 劉瑞春. "Effect of Surface Treatment of Silicate Sealant on Concrete Properties." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/34538667380762217064.
Full text國立海洋大學
河海工程學系碩士在職專班
91
Abstract Cracks and porosities are the main causes affecting concrete durability. If effective sealant is applied on the concrete surface during construction or after construction, the surface pores can be filled. The surface treatment may reduce permeability and increase concrete durability, and thus reduce the maintenance expenses. Eventually, the life cycle cost of reinforced concrete will be minimized. Two types of silicate sealants were investigated in this study. Sealants were analyzed using SEM and XRD. Concrete specimens cast with two water/cement ratios were tested for compressive strength, splitting strength, modulus of elasticity and sulfate resistance. Test results show that there is not much different in strength performance between treated and untreated specimens. The X-type sealant has larger penetration depth than P-type sealant based on calcium/silica ratio. The optimum dosage of X-type sealant is 1.0 kg/m2 and the specimens treated with P-type have largest weight loss in sulfate immersion test. In conclusion, the positive effect of X-type sealant on concrete properties is verified in this study.
Alkilzy, Mohammad [Verfasser]. "Therapeutic sealing of proximal tooth surfaces: two-year clinical and radiographic evaluation / vorgelegt von Mohammad Alkilzy." 2009. http://d-nb.info/995936110/34.
Full textRitchie, Craig D. 1970. "A comparison of hardness and abrasion resistance of two sealant materials after polymerization from different distances by different light sources." Thesis, 2008. http://hdl.handle.net/1805/4378.
Full textBACKGROUND The efficacy of sealants to aid in the prevention of pit and fissure caries is well documented. In order for the sealants to be effective, they must be placed properly and retained for as long as possible. Clinicians must be aware that the proper placement of sealants is technique-sensitive and must be well controlled in order to achieve the best results. This study aims to determine if certain variables have an effect on curing of the sealant material to a degree that would compromise its integrity, strength, and longevity. METHODS AND MATERIALS Two commonly used sealant materials Ultraseal XT (Ultradent Products Inc., South Jordan, UT) and Delton (Dentsply International, Woodbridge, Ontario, Canada) were chosen and tested for microhardness and abrasion resistance after they were polymerized. This study did not focus on the materials themselves, but rather the technique by which they were polymerized and what effect this had on the materials. Three separate light sources, a traditional halogen light (QHL 75, Dentsply International, Woodbridge, Ontario, Canada), and two newer LED lights (Ultralume LED, Ultradent Products Inc., South Jordan, UT; and 3M Freelight LED, 3M Corp, St Paul, MN) were used in this study. The materials were then cured with each light at each of three different distances: contact (0.5 mm), 2 mm, and 10 mm. The effects of light source variation and distance from the material at the time of polymerization was then evaluated for any significance to sealant placement technique. Specimens were tested for each variable combination of sealant material, light source, and distance between the two while curing. Six samples were tested for each variable grouping for abrasion resistance, and four separate san1ples were tested fron1 the san1e grouping for Knoop hardness. The results were analyzed for significance to determine if certain techniques are or could be beneficial or damaging to the quality of care provided by today's practitioners. RESULTS It was found that materials and light sources varied in combination and with different techniques (e.g., distance). In general, the top surface polymerized best when cured at a distance of 2 mm to 10 mm, while the bottom surface polymerized best at a distance of 0.5 mm. The halogen light consistently outperformed the two LED lights, with the 3M LED consistently producing the worst results. CONCLUSIONS The halogen curing light used in this study outperformed the LED lights in almost every category, despite the LED light manufacturer's claims of equality. For more reliable polymerization, the halogen light should be used. SIGNIFICANCE The practitioner must be aware of the material that he/she is using and how the chosen light source polymerizes that material. Manufacturers' claims and recommendations cannot be trusted to accurately produce the best results with every product on the market today, sometimes not even with the manufacturers' own products. It is crucial for practitioners to be well versed and knowledgeable about the products that they use, based on current research and not manufacturers' claims.
Folke, Bernadette Delumpa. "Sealant success rates among dentists, dental assistants, and dental hygienists in a pediatric dental office using a surface enameloplasty technique a retrospective study : a thesis submitted in partial fulfillment ... for the degree of Master of Science in Pediatric Dentistry ... /." 2002. http://catalog.hathitrust.org/api/volumes/oclc/68962502.html.
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