Natalia Cristina de Mendonça Spera

Natalia Cristina de Mendonça Spera
International Iberian Nanotechnology Laboratory · Nanochemistry

Master of Science

About

12
Publications
699
Reads
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6
Citations
Introduction
MSc. in Materials Science and Engineering. Specialist in Production Engineering. Aircraft Maintenance Technologist.
Additional affiliations
February 2021 - present
International Iberian Nanotechnology Laboratory
Position
  • Engineer
February 2019 - July 2019
Virtual University of São Paulo
Position
  • Instructor
Description
  • Mentoring and answer students' questions, correct activities, and tests. Teaching support: Materials Science and Materials Resistance.
February 2017 - December 2018
Federal Institute of Education, Science and Technology of São Paulo
Position
  • Professor
Education
August 2015 - June 2019
University of São Paulo
Field of study
  • Materials Science and Engineering
February 2015 - November 2016
University of São Paulo
Field of study
  • Production Engineering
February 2012 - December 2014

Publications

Publications (12)
Article
Full-text available
Proton Exchange Membrane (PEM) water electrolysis (WE) produces H2 with a high degree of purity, requiring only water and energy. If the energy is provided from renewable energy sources, it releases “Green H2”, a CO2-free H2. PEMWE uses expensive and rare noble metal catalysts, which hinder their use at a large industrial scale. In this work, the e...
Article
Full-text available
The in situ formation of mullite (Al6Si4O13) is a complex process based on solid-state reactions strongly affected by the characteristics of Al2O3 and SiO2 sources. This study investigated the combined effects of variable SiO2/Al2O3 ratios and the presence of low-melting-point impurities on the physical properties and microstructure of in situ alum...
Article
Full-text available
Colloidal silica (CS) is a promising raw material for refractory castable ceramics. It consists of stable suspensions of synthetic amorphous silica nanoparticles that behave simultaneously as liquid medium and binder for ceramic particles and as a porogenic agent and highly reactive source of silica to promote in-situ reactions. The setting mechani...
Article
Full-text available
There is a clear need for learning other languages when it comes to aeronautics, since most of the manufacturers and companies that provide services such as maintenance, development of projects and airlines are present worldwide. For restoration, aeronautical mechanics use aircraft’s manuals to perform their daily tasks, which are mostly in English...
Thesis
Improvements in energy efficiency motivate the development of more effective and durable thermal insulation. Porous ceramics based on mullite (Al6Si2O13 or 3Al2O3.2SiO2) have great potential for this application due its high resistance to corrosion and densification. Although rare in its mineral form, this is one of the most important phases in tra...
Conference Paper
Full-text available
Mullite (3Al 2 O 3 ·2SiO 2) has good thermal mechanical properties and is commonly applied as refractory ceramics. Using colloidal silica, may improve particles reactivity, sinterability and mullite formation, for the in situ reaction with calcined alumina (-Al 2 O 3). This study evaluated castable suspensions of pre-calcined aluminum hydroxide (A...
Conference Paper
Full-text available
Researches involving self-healing materials have gain importance due to their capability of longer life cycles of products. The present study investigates one ionomer and its ability to heal with thermal stimulus after low energy damages, such as scratch detriments. The polymer films were adhered to a metallic substrate by hot-pressing and damaged...
Thesis
Full-text available
In aviation, the maintenance has a fundamental key role in ensuring the safety of passengers, crew and everyone directly involved with the aircraft. Over time, companies specialized in these activities appeared, now known as MRO Centers that stands for Maintenance, Repair and Overhaul. To control the activities carried out by these centers, each co...
Conference Paper
Full-text available
Self-healing ionomer has proven the ability to autonomous heal after a damage event in room temperature. The present study intent to investigate the self-healing response of microcracks in an ionomer polymer partially neutralized upon bullet penetration in cryogenic conditions. The specimens were obtained by hot press of pellets and after ballistic...
Article
Full-text available
Knowing English is essential in aviation field mainly because the communication among people who work in this area is done through this language. In attempt to reduce miscommunication, the international Civil Aviation Organization (ICAO) determined as mandatory the proficiency for these professionals tested through global tests for language harmoni...

Questions

Question (1)
Question
What are the ISO, ASTM to evaluate coatings with self-healing properties?

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Cited By

Projects

Projects (3)
Archived project
Evaluate the potential self-healing response of thermoplastic ionomers after damage and heat treatment.
Archived project
Investigation of the reading strategies used by aircrafts mechanics in order to understand technical procedures written in English.
Project
Refractory porous ceramics are essential materials for most of high-temperature (500-2000°C) processes in steelmaking, petrochemical, foundry, and cement industries thanks to their combination of refractoriness (high melting point, thermomechanical strength and chemical stability) and functionality (tailored porosity, permeability and thermal conductivity and diffusivity). Castable systems (those that are shaped from aqueous suspensions and set by means of binders) also have additional advantages, such as freedom for designing complex geometries and their straightforward and energy-saving installation (because they do not need previous sintering before use). Their thermomechanical properties and usefulness at high-temperature are directly linked to the processing techniques employed in their production and their composition and microstructure at the green state (before first heating). In this research line, particles of high-refractoriness compounds, such as alumina (α-Al2O3), magnesia (MgO), lime (CaO), and silica (SiO2), are combined with inorganic porogenic agents (Al(OH)3, rho-Al2O3, Mg(OH)2, Mg6Al2(CO3)(OH)16.4H2O, CaCO3, and CaAl2O4.10H2O) to produce stable castable aqueous suspensions. After curing and drying, their microstructure and properties are evaluated during the first heating and after full sintering. The main challenges we have to overcome are: a) Careful characterization of the ceramics particles of the raw materials (geometry, size distribution, aspect ratio, density, specific surface área, inner porosity); b) Preparation of stable aqueous multi-particles dispersions (or co-dispersions) with suitable rheological characteristics for mixing (time-energy consumption, homogenization, Zeta potential) and casting (high-solid load combined with low viscosity, yield stress and dilatant behavior); c) understand and foresee the microstructure and composition changes that may occur during the initial heating (for instance pores generation and linear expansion due to the formation of low-density compounds) using physical characterization techniques (XRD, SEM/TEM, TGA/DSC/dilatometric analysis, thermomechanical tests); d) Evaluate the properties of the porous structures attained (total porosity, permeability, pores size distribution and shape, thermomechanical strength, specific heat, linear thermal variation, thermal conductivity and diffusivity).