A5013281360- Laser Material Processing Techniques
- Advanced Surface Polishing Techniques
- Laser-induced spectroscopy and plasma
- Metal and Thin Film Mechanics
- Welding Techniques and Residual Stresses
- Glass properties and applications
- Laser Applications in Dentistry and Medicine
- Ocular and Laser Science Research
- Nonlinear Optical Materials Studies
- Solid State Laser Technologies
- Laser Design and Applications
- Additive Manufacturing Materials and Processes
- Tribology and Lubrication Engineering
- Dental materials and restorations
- Diamond and Carbon-based Materials Research
- High Entropy Alloys Studies
- Dental Erosion and Treatment
- Laser-Matter Interactions and Applications
- High-Temperature Coating Behaviors
- Adhesion, Friction, and Surface Interactions
- Optical Coherence Tomography Applications
- Advanced Fiber Laser Technologies
- Surface Roughness and Optical Measurements
- Hydrogen embrittlement and corrosion behaviors in metals
- Laser-Ablation Synthesis of Nanoparticles
National Nuclear Energy Commission
2014-2025
Instituto de Pesquisas Energéticas e Nucleares
2016-2025
Nuclear Engineering Institute
2004-2017
Centro Laser
2009-2017
Universidade Federal do Rio Grande do Sul
2017
Energy Research Institute
2015
Canadian Linguistic Association
2010-2012
Brazilian Center for Research in Energy and Materials
2002
Experimental investigations were carried out using a pulsed neodymium:yttrium aluminum garnet laser weld to examine the influence of pulse energy in characteristics fillet. The was varied from 1.0 2.25 J at increments 0.25 with 4 ms duration. base material used for this study AISI 316L stainless steel foil 100 μm thickness. welds analyzed by optical microscopy, tensile shear tests and microhardness. results indicate that control is considerable importance thin quality because it can generate...
Gold nanoparticles are widely used in biomedical applications due to their unique properties. However, traditional synthesis methods generate contaminants that cause cytotoxicity and compromise the biocompatibility of nanomaterials. Therefore, green essential produce pure biocompatible nanoparticles, ensuring effectiveness applications. This study introduces a novel approach for synthesizing silica-coated gold (AuNP@SiO₂) using femtosecond laser ablation water, eliminating need chemical...
This study is focused on the fabrication and characterization of various dual waveguides through femtosecond (fs) laser irradiation GeO2-based glass samples. The objective present work to develop diverse waveguide configurations, namely straight, S-bend Y-shaped within GeO2-PbO glasses embedded with silver nanoparticles, utilizing a double-guide platform, for photonic applications such as resonant rings beam splitters. Enhanced guidance was observed larger radius curvature (80 mm) among two...
The use of radiopharmaceuticals labelled with fluorine-18 in non-invasive imaging, particularly Positron Emission Tomography (PET), increased significantly during the last decade. However, traditional nucleophilic fluorination synthesis methods most cases require azeotropic drying steps, leading to loss activity and time. Microfluidic devices offer improvements shorter reaction times, higher elution efficiency, reduced reagent quantities. We developed a novel micro-cartridge for...
We report the validation of Diagonal Scan (D-Scan) technique to determine incubation parameter for ultrashort laser pulses ablation. A theory calculate superposition and a procedure quantifying effects are described, results obtained BK7 samples in 100 fs regime compared ones given by traditional method, showing good agreement.
The aim of the present in vitro study was to evaluate, using two different methodologies, effectiveness pulsed Nd:YAG laser irradiation associated with topical acidulated phosphate fluoride (APF) for preventing enamel erosion and structure loss under regimes abrasion or only.An increased incidence noncarious lesions (erosion abrasion) has been observed, consequently new preventative therapies have proposed.Two methodologies were performed. For first, 100 bovine crowns submitted four...
Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced double line waveguides through fs laser processing for photonic applications. A Ti:sapphire at 800 nm was used to write the directly into 0.7 mm beneath surface. This platform is based on pairs of parallel lines spacing 10 µm, each pair being formed by two identical written but in different configurations 4 or 8 separately processed lines, which coincident. The results optical microscopy, absorbance measurements,...
Previous research in our laboratory has shown that the polarization component of electrical field plays an important role on healing process inflammatory lesions created end spinal column Lewis rats, using a He-Ne laser at λ = 632.8 nm. It is well known lost turbid medium, such as living tissue. However, Nd:YLF wavelength (λ 1,047 nm) allows more preservation than nm, and beam been used clinical trials biostimulating agent. In this work, we investigated influence low-intensity, linearly...
In this work, the morphology of solidification weld zone (WZ) was studied in a joint formed from dissimilar materials, composed austenitic AISI 304 stainless steel and Inconel 600 nickel alloy, welded with an Nd:YAG-pulsed laser. The laser beam optical system parameters were selected view to obtain total penetration good surface finish. microstructural characterization carried out using microscope, which WZ seen penetration, keyhole-type, presence small pores absence cracks. joints also...
In this study a pulsed Nd:YAG laser was used to join Monel 400 thin foil with μm thickness. Pulse energy varied from 1.0 2.25J at small increments of 0.25J. The macro and microstructures were analyzed by optical microscopy, tensile shear test microhardness. Sound welds without discontinuities obtained 1.5 J pulse energy. Results indicate that using precise control the energy, so bottom dilution rate, it is possible weld foil. process appeared be very sensitive gap between couples.
In this study a pulsed Nd:YAG laser was used to join Hastelloy C-276 thin foil with 100 microns thickness. Pulse energy varied from 1.0 2.25 J at small increments of 0.25 4 ms pulse duration. The macro and microstructures the welds were analyzed by optical electronic microscopy, tensile shear test microhardness. Sound without discontinuities obtained 1.5 energy. Results indicate that using precise control energy, so dilution rate, it is possible weld laser.
Damage threshold and ablation rate measurements were performed on Bk7 glass for femtosecond single multipulses. The incubation parameter was found used to develop a new strategy machining microchannels in Bk7. Optical Coherent Tomography - OCT showed that this process can be effective obtaining deep, well defined square cross section with no cracks or resolidified material. It also verified useful detecting small index refraction changes induced the surround of machined area.
Non-invasive methods such as X-ray Fluorescence has been applied to study of the distinct pathologies and contamination levels analysis in various biological tissues among them nails, hair, tooth. On other hand, several works have demonstrated that laser could be induced chemical morphological alterations on enamel surface occupying an important role co-adjuvant caries disease prevention. Here, we combined fluorescence using Fundamental Parameters method aiming evaluate variation contend....
Thousands of people die every year from burn injuries. The aim this study is to evaluate the feasibility high intensity femtosecond lasers as an auxiliary treatment skin burns. We used in vivo animal model and monitored healing process using 4 different imaging modalities: histology, Optical Coherence Tomography (OCT), Second Harmonic Generation (SHG), Fourier Transform Infrared (FTIR) spectroscopy. 3 dorsal areas 20 anesthetized Wistar rats were burned by water vapor exposure subsequently...