Ultrasonic Vibration
Mostrando 1-12 de 16 artigos, teses e dissertações.
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1. Ultrasonic method of microvibration detection: part II - additional processing method and applications
Abstract Introduction In the last 28 years, the scientific community has been using elastography to evaluate the mechanical properties of biological tissue. The aim of this work was the optimization of the UDmV method, presented in Part I of the series, by means of modifying the technique employed to generate the reference sine and cosine functions, used fo
Res. Biomed. Eng.. Publicado em: 17/08/2017
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2. Comparison of different ultrasonic vibration modes for post removal
Este estudo in vitro comparou diferentes modos de vibração ultra-sônica na remoção de pinos intra-radiculares fundidos. As coroas de 24 caninos superiores foram removidas, as raízes foram incluídas em blocos de resina acrílica e tratadas endodonticamente. Os espaços para os pinos intra-radiculares foram preparados e depois moldados com resina acríl
Brazilian Dental Journal. Publicado em: 2012
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3. The effectiveness of chemical denture cleansers and ultrasonic device in biofilm removal from complete dentures
Adequate denture hygiene can prevent and treat infection in edentulous patients. They are usually elderly and have difficulty for brushing their teeth. OBJECTIVE: This study evaluated the efficacy of complete denture biofilm removal using chemical (alkaline peroxide-effervescent tablets), mechanical (ultrasonic) and combined (association of the effervescent
Journal of Applied Oral Science. Publicado em: 2011-12
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4. Utilização de medições ultrassônicas de vibração e da emissão acústica para implantação de lubrificação base-condição visando a prevenção de falhas em mancais de rolamentos
Este trabalho tem por objetivo apresentar uma técnica de identificação de falhas em mancais de rolamento até então praticamente inexistente no Brasil. Ela refere-se à mudança da tradicional lubrificação base-tempo, baseada em recomendações de fabricante e fórmulas retiradas de ábacos clássicos para a lubrificação base-condição. Mancais de r
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2011
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5. Aplicação de ultrassons no deslocamento de petróleo em meio poroso / Ultrasound application to promote petroleum displacement in porous media
O objetivo desse trabalho foi avaliar o deslocamento de soluções de petróleo/diesel, em diferentes concentrações, observando o efeito das vibrações ultrassônicas no deslocamento dos fluidos presentes em meio poroso para obter um aumento na produção de petróleo. As bolhas formadas pelo ultrassom implodem na rocha de forma assimétrica, gerando jato
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/11/2010
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6. Effect of the simulated periodontal ligament on cast post-and-core removal using an ultrasonic device
ABSTRACT OBJECTIVE: The aim of this study was to evaluate the effect of simulated periodontal ligament (SPDL) on custom cast dowel and core removal by ultrasonic vibration. MATERIAL AND METHODS: Thirty-two human maxillary canines were included in resin cylinders with or without SPDL made from polyether impression material. In order to allow tensile testing,
Journal of Applied Oral Science. Publicado em: 2010-10
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7. Analysis of 1-3 piezocomposite and homogeneous piezoelectric rings for power ultrasonic transducers
Some power ultrasonic transducers, such as Tonpilz transducers, require high-power transmitting capability as well as broadband performance. Optimized vibrational modes can achieve these requirements. This work compares the resonant characteristics and the surface vibration modes between a homogeneous piezoelectric ring and a 1-3 piezocomposite ring, both us
Journal of the Brazilian Society of Mechanical Sciences and Engineering. Publicado em: 2009-12
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8. Influence of luting agents on time required for cast post removal by ultrasound: an in vitro study
OBJECTIVE: This in vitro study evaluated the influence of luting agents on ultrasonic vibration time for intraradicular cast post removal. MATERIAL AND METHODS: After endodontic treatment, 30 roots of extracted human canines were embedded in resin cylinders. The post-holes were prepared at 10 mm depth and their impressions were taken using autopolymerizing a
Journal of Applied Oral Science. Publicado em: 2009-06
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9. Comparison of the time required for removal of intraradicular cast posts using two Brazilian ultrasound devices
The aim of this in vitro study was to compare the time required for removal of intraradicular cast posts cemented with zinc phosphate (ZF) or glass ionomer cement (GIC), using two Brazilian ultrasound devices (BUD). Seventy two human inferior premolars with single root canals were sectioned transversally at the cementoenamel junction. In each specimen, the r
Brazilian Oral Research. Publicado em: 2009-03
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10. Clinical evaluation of the efficacy on biofilm removal from complete denture of the chemical (alkaline peroxide) and mecanical (ultrasonic) methods / Avaliação clínica da eficácia dos métodos químico (peróxido alcalino) e mecânico (ultra-som) frente à propriedade de remoção do biofilme de próteses totais
The aim of this study was to evaluate the hability of the biofilm removal from complete denture of the chemical (alkaline peroxide-effervescent tablets to complete denture immersion), mechanical (ultrasonic) and combined (association of the effervescent and ultrasonical methods) methods. Eighty patients that use upper and lower complete denture participated
Publicado em: 2007
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11. Influencia da vibração na permeabilidade absoluta de meios porosos saturados com agua / Influence of the vibration on the absolute permeability of porous media satured with water
This work verifies experimentally the effects of the mechanical vibration on the absolute permeability of saturated porous media upon which a uniform flow is simultaneously imposed. After finding a driving range within which indirect effects of the vibration are excluded, such as those resulting from ultrasonic heating and mechanical disintegration of the ro
Publicado em: 2004
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12. Contribuição ao estudo tribologico dos pares acionadores de motores ultra-sonicos
A tribological study of the potential materials to be employed in linear ultrasonic motors is presented. Different pairs of materiais such as steel/alumina, steel/diamond, alumina/diamond and diamond/diamond have been studied. The diamond samples were obtained by chemical vapor deposition (CVD) and used in the ultrasonic pairs without any previous polishing.
Publicado em: 1996