A5025376946- Chalcogenide Semiconductor Thin Films
- Graphene research and applications
- Graphene and Nanomaterials Applications
- Quantum Dots Synthesis And Properties
- Natural Fiber Reinforced Composites
- Fiber-reinforced polymer composites
- Pigment Synthesis and Properties
- solar cell performance optimization
- Membrane Separation Technologies
- Mechanical Behavior of Composites
- Copper-based nanomaterials and applications
- Electrospun Nanofibers in Biomedical Applications
- Water Quality Monitoring and Analysis
- Tribology and Wear Analysis
- Polymer Nanocomposites and Properties
- Carbon Nanotubes in Composites
- Transition Metal Oxide Nanomaterials
- High Temperature Alloys and Creep
- Academic Research in Diverse Fields
- Synthesis and properties of polymers
- Agricultural and Food Sciences
- Perovskite Materials and Applications
- Business and Management Studies
- Fatigue and fracture mechanics
- Magnetic Properties and Synthesis of Ferrites
Military Institute of Engineering
2015-2024
University of Manchester
2018
Universidade de Brasília
2015
Universidade de São Paulo
2013
Composites with sustainable natural fibers are currently experiencing remarkably diversified applications, including in engineering industries, owing to their lower cost and density as well ease processing. Among the fibers, fiber extracted from leaves of Amazonian curaua plant (Ananas erectifolius) is a promising strong candidate replace synthetic such aramid (Kevlar™), multilayered armor system (MAS) intended for ballistic protection against level III high velocity ammunition. Another...
A recent strategy that has emerged for the design of increasingly functional hydrogels is incorporation nanofillers in order to exploit their specific properties either modify performance hydrogel or add functionality. The emergence carbon nanomaterials particular provided great opportunity use graphene derivatives (GDs) biomedical applications. key challenge when designing hybrid materials understanding molecular interactions between matrix (peptide nanofibers) and nanofiller (here GDs) how...
In the present work, two types of composites were produced, both reinforced with 30 vol% curaua fibers (CF). first type, only fiber was functionalized graphene oxide (GO), producing GOCF/EM composite. While in second, epoxy matrix (EM) functionalized, CF/GOEM The objective work to investigate influence functionalization GO on tensile properties these produced composites. comparison non GO-functionalized composite, as control CF/EM, results revealed an increase yield strength (64%), (40%),...
Twaron® brand aromatic polyamide, commonly known as aramid fabric, was reinforced with a solution of graphene oxide (GO) followed by heat treatment at 120 °C. The objective to improve the ballistic properties material increasing friction coefficient fibers in fabric. GO produced modified Hummers method characterized Fourier transform infrared and Raman spectroscopy well scanning electron microscopy (SEM) atomic force microscopy. Both as-received fabric coated one two filtrations were...
Graphene oxide (GO) incorporation in natural fiber composites has recently defined a novel class of materials with enhanced properties for applications, including ballistic armors. In the present work, performance 0.5 vol % GO-incorporated epoxy matrix composite reinforced 30 fabric made ramie fibers was investigated by stand-alone tests against threat 0.22 lead projectile. Composite characterization also performed Fourier-transform infrared spectroscopy, thermal analysis and X-ray...
The aim of this work is to characterize properties and microstructure AISI 316L stainless steel used as a coating on welding carbon sheets. Two plates were set the metal base was applied weld bead. process submerged arc (SAW) tests carried out for tensile strength Vickers hardness, in addition observation by optical microscopy. results indicated that stainless-steel bead provided relatively high values strength. Moreover, hardness suggest investigated innovative material can be corrosive...
The coating of natural fiber by graphene oxide (GO) has, over, this past decade, attracted increasing attention as an effective way to improve the adhesion polymer matrices and enhance composite properties. In particular, GO-functionalized 30 vol% curaua (Ananas Erectifolius) reinforcing epoxy was found display superior tensile thermogravimetric properties well higher fiber/matrix interfacial shear strength. brief report, dynamic mechanical analysis (DMA) conducted in up 50 reinforced matrix...
Stainless steels are well known by their corrosion resistance. The austenitic types, in particular, also applied as structural components engineering systems operating at high temperatures such nuclear reactors, petrochemical furnaces and turbines. For these applications operational may go up to 800ºC. Under constant load the main mechanism of failure, which would limit material's life, is creep. In present work creep parameters were evaluated temperature interval 600 800ºC for an AISI 316...
The rapid advancements in nanotechnology have spurred the search for more efficient materials across various advanced applications. To this end, study aimed to synthesize and investigate structural properties of copper ferrite mixed copper-silver anchored onto reduced graphene oxide (rGO) sheets. Samples were synthesized via hydrothermal method at four different temperature ranges 6 h pH 11. systems analyzed using Raman spectroscopy, X-ray diffraction (XRD), Scanning Electron Microscopy...
Unlike other thin film deposition techniques, close spaced sublimation (CSS) requires a short source-substrate distance. The kind of source used in this technique strongly affects the control parameters, especially rate. When depositing CdTe films by CSS, most common sources are: single-crystal or polycrystalline wafers, powders, pellets pieces, thick deposited onto glass molybdenum substrate (CdTe source-plate) and sintered powder. In work, were CSS from different sources: particles,...
CdTe thin films are used as absorber layer in CdS/CdTe solar cells. The microstructure of this plays a fundamental role photovoltaic conversion and can be controlled by the deposition parameters during film growth. In work, were deposited CSS method onto glass substrates previously covered with In2O3:Sn. effects pressure, source temperature substrate on microstructural properties studied. mainly influenced presence oxygen reaction chamber, temperature. For under an argon atmosphere, increase...
Graphene oxide (GO) functionalized curaua fiber (CF) has been shown to improve the mechanical properties and ballistic performance of epoxy matrix (EM) nanocomposites with 30 vol% fiber. However, possibility further improvement in property a greater percentage GO CF is still challenging endeavor. In present work, novel composite reinforced 40 coated 0.1 wt% (40GOCF/EM), was subjected Izod impact tests as well corresponding fractographic analysis comparison GO-free (40CF/EM). One important...
Methylammonium lead iodide (CH3NH3PbI3) perovskite has been proposed as a key component of thin film solar cells. In this work, the influence substrate temperature on properties spray deposited CH3NH3PbI3 films was investigated. The main purpose work to determine best conditions deposit and crystallize in single step. An automatic system used for depositing solution methylammonium onto heated substrates under ambient just one second. After deposition samples were held at same 30 s. varied...
RESUMO Neste trabalho foram preparadas dispersões aquosas de óxido grafeno (GO) e reduzido (rGO), em diferentes tempos oxidação, com o objetivo verificar a influência do tempo oxidação relação às características das folhas (flakes) finais. As GO pelo método Hummers modificado utilizando os seguintes oxidação: 4 h; 1 dia; 3 dias; 7 dias 10 dias. Em seguida, as submetidas ao tratamento redução ácido ascórbico, obtendo-se rGO. caracterizações amostras realizadas por meio análises espectroscopia...
This work compares the properties of CdS films deposited by CBD and CSS techniques. The influence deposition parameters on was investigated. thickness ranged from 80 to 100nm affected concentration reactants in solution. For films, controlled 100-300nm range, being strongly influenced source/substrate temperatures pressure. Grain size larger than films. Transmittance 90%, but band gap narrower which means that transmit less blue part solar spectrum However, growth technique may be...
In this work CdS/CdTe solar cells were submitted to solution, sublimation and vapor CdCl <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> treatments, followed by NP etch for several periods of time. The influence these procedures on cell efficiency is discussed. individual layers are analyzed the results compared with similar studies in literature. best etching time was 20 s all treatments. highest achieved solution treatment at 380 °C....
This work reports the process used to manufacture CdS/CdTe thin film solar cells at Instituto Militar de Engenharia (IME). The procedure consists of sequentially depositing several layers onto a glass substrate, config- ured as glass/TCO/CdS/CdTe/Au. Analysis individ- ual showed that films had minimum re- quirements yield efficient devices. use different TCOs did not improve device efficiency, probably due other more important loss mechanisms. available system in laboratory for measurement...