Laser Cooling
Mostrando 1-12 de 45 artigos, teses e dissertações.
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1. Effect of Scanning Speed on the Surface Roughness of Laser Metal Deposited Copper on Titanium Alloy
This paper reports on the effect of scanning speed on the laser deposited Cu on titanium alloy substrate. The experiments were conducted by varying the scanning speed from 0.3 m/min to 1.2 m/min while the laser power, the powder feed rate and the gas flow rate were kept constant. The laser deposited Cu were characterized through the evolving microstructure a
Mat. Res.. Publicado em: 20/12/2019
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2. Damping of Fe-Al Alloy Electrodeposited in an Ionic Liquid
Iron-Aluminium alloys were produced by the electro-deposition of iron-aluminium on a copper substrate. The electro-deposition process was done in the ionic liquid 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate, [Py1,4]TfO. A solution of (0.2 M FeCl2 + 2.75 M AlCl3)/ [Py1,4] TfO was used at a temperature of T=363 K because this mixture is solid at roo
Mat. Res.. Publicado em: 11/10/2018
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3. Laser cooling techniques: standard and alternated optical molasses
The technique of laser cooling, whose basic idea was proposed in 1975 [1], provided the development of many important areas like high-resolution spectroscopy [2], atomic clocks [3] and quantum gases confined in magnetic or optical traps [4, 5]. Among the techniques applied to cooling neutral atoms is the optical molasses [6] that will be explored in this wor
Rev. Bras. Ensino Fís.. Publicado em: 22/05/2017
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4. Design of conformal cooling for plastic injection moulding by heat transfer simulation
The cooling channels of a mold for plastic injection have to be as close as possible to the part geometry in order to ensure fast and homogeneous cooling. However, conventional methods to manufacture cooling channels (drilling) can only produce linear holes. Selective laser melting (SLM) is an additive manufacturing technique capable to manufacture complex c
Polímeros. Publicado em: 2015-12
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5. Investigation on the Microstructure of Direct Laser Additive Manufactured Ti6Al4V Alloy
Direct laser fabrication (DLF) is one of the advanced near-net shape processing technologies. The variations of laser parameters can change the energy distribution within a laser scan, and thus affect the cooling rate, and resulting microstructure of deposited material. In this study, the effect of the laser parameters on the microstructure of additive laser
Mat. Res.. Publicado em: 24/11/2015
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6. The combined use of Er,Cr:YSGG laser and fluoride to prevent root dentin demineralization
The use of erbium lasers to prevent caries in enamel has shown positive results. However, it is not known if Er,Cr:YSGG laser can also be used to increase acid resistance of root dentine, which is another dental tissue susceptible to the action of cariogenic bacteria. Objective: To analyze the effects of the Er,Cr:YSGG laser (λ=2.78 μm, 20 Hz) irradiation
J. Appl. Oral Sci.. Publicado em: 2014-10
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7. Phase transformations in an AISI 410S stainless steel observed in directional and laser-induced cooling regimes
The applications of the chromium ferritic stainless steel AISI 410S have been considerably increased in the last years in many technical fields as chemical industries and oil or gas transportation. However, the phase transformation temperatures are, currently, unknown for this alloy. The aim of this work is to determine the alpha to gamma transformation temp
Materials Research. Publicado em: 31/01/2012
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8. Avaliação do efeito da associação da irradiação laser Er:YAG com flúor no esmalte dental submetido à erosão / Evaluation of the association effect of the Er:YAG laser irradiation with fluoride on enamel submitted to the erosion
The dental erosion is a lesion caused by loss of enamel mineral due to the acids action originated from gastric juice or dietary. The aim of this study was to evaluate the effectiveness of the Er:YAG laser on the prevention of enamel erosion associated or not to the fluoride, and to evaluate chemical and morphological changes of enamel after preventive treat
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 10/01/2011
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9. Análise morfológica e da resistência adesiva dos tecidos dentais duros irradiados com lasers de pulsos ultracurtos / Evaluation of dental hard tissues irradiated with ultra-short pulsed lasers. Influence on surface morphology and microtensile bond strength
The development of restorative dentistry has reached the era of esthetic adhesive restorations and minimally invasive approach, for which innovative techniques and advanced materials are constantly introduced. Conservative techniques aim not only to remove carious dental substrate, but also to prepare cavity surfaces for adhesive restoration. The main object
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 16/09/2010
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10. Simulação de resfriamento a laser em armadilha magnética e construção de laser de cavidade estentida / Simulation of laser cooling in magnetic trap and building of laser with extended cavity
O resfriamento a laser em altos campos magnéticos, apresenta uma série de dificuldades devido ao alargamento inomogêneo da transição causado pelo efeito Zeeman. Na primeira parte desse trabalho investigamos o resfriamento a laser de Lítio através de uma simulação de Monte Carlo, na transição 2S1/2 ->2P3/2 em 670.96 nm, em uma armadilha magnética
Publicado em: 2010
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11. DESENVOLVIMENTO DE UM PADRÃO DE REFERÊNCIA METROLÓGICA DE FREQÜÊNCIA LASER EM TORNO DE 532 NM / DEVELOPMENT OF A METROLOGICAL STANDARD LASER FREQUENCY REFERENCE AT 532 NM
This work is part of the project for development of the first metrology reference for frequency standard around 532 nm in Brazil for the practical realization of the definition of the meter. The study was conducted at the Laboratory Interferometry (Laint) Inmetro, through an agreement with the Posgraduation Program in Metrology for Quality Industrial, PUC-Ri
Publicado em: 2009
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12. Transient solidification, microstruture and properties of Al-Ni alloys / Solidificação transitoria, microestrutura e propriedades de ligas Al-Ni
The development of optimized microstructures during the solidification stage of processing is of fundamental importance to the mechanical properties and to the performance of finished products of metallic alloys. In this study the kinetics of solidification and its effects on macro and microstructural parameters, as well as the consequent influence on the fi
Publicado em: 2009