Papers by mickael da silva
National audienceA ce jour, les meilleurs rendements de conversion photovoltaïque ont été obtenus... more National audienceA ce jour, les meilleurs rendements de conversion photovoltaïque ont été obtenus avec des cellules solaires multi-jonctions à base de matériaux semi-conducteurs III-V monocristallins sous éclairement solaire concentré. Cependant, le recours aux substrats III-V dans la fabrication de cellules solaires à haut rendement pose le problème des coûts conséquents de ces matériaux. Afin de relever le défi stratégique d’un coût de 0.25-0.5 Euro/Wp, nous avons opté pour l’utilisation du substrat silicium, qui est très abondant sur Terre et donc bon marché. L’intégration monolithique d’hétérostructures III-V sur silicium permettrait de concilier à la fois hauts rendements et bas coûts, tout en capitalisant sur une filière industrielle éprouvée. Nous explorons deux approches de cellules III-V sur Silicium : les cellules tandem et les hétérojonctions.Une cellule solaire tandem, constituée d’une cellule III-V à 1.7 eV sur une cellule c-Si à 1.1 eV, permettrait théoriquement d’atte...
Innuendo Whole Genome And Core Genome Mlst Schemas And Datasets For Yersinia Enterocolitica
<strong>Dataset</strong> All the raw reads deposited in the European Nucleotide Archi... more <strong>Dataset</strong> All the raw reads deposited in the European Nucleotide Archive (ENA) or in the NCBI Sequence Read Archive (SRA) as <em>Y. enterocolitica</em> at the time of the analysis (August 2018) were retrieved using getSeqENA. A total of 252 genomes were successfully assembled using INNUca v3.1. In addition to public available genomes, the database includes 79 novel <em>Y. enterocolitica</em> strains which belong to the INNUENDO Sequence Dataset (PRJEB27020). File 'Metadata/Yenterocolitica_metadata.txt' contains metadata information for each strain including country and year of isolation, source classification, taxon of the host, serotype, biotype, pathotype (according to patho_typing software) and classical pubMLST 7 genes ST according to Hall et al., 2005. The directory 'Genomes' contains all the 331 INNUca V3.1 assemblies of the strains listed in 'Metadata/Yenterocolitica_metadata.txt'. <strong>Schema creation and validation</strong> All the 331 genomes were used for creating the schema using <strong>chewBBACA suite</strong>. The quality of the loci have been assessed using <em>chewBBACA Schema Evaluation</em> and loci with single alleles, those with high length variability (i.e. if more than 1 allele is outside the mode +/- 0.05 size) and those present in less than 1% of the genomes have been removed. The wgMLST schema have been further curated, excluding all those loci detected as "Repeated Loci" and loci annotated as "non-informative paralogous hit (NIPH/ NIPHEM)" or "Allele Larger/ Smaller than length mode (ALM/ ASM)" by the <em>chewBBACA Allele Calling</em> in more than 1% of a dataset. File 'Schema/Yenterocolitica_wgMLST_ 6344_schema.tar.gz' contains the wgMLST schema formatted for chewBBACA and includes a total of 6,344 loci. File 'Schema/Yenterocolitica_cgMLST_ 2406_listGenes.txt' contains the list of genes from the wgMLST schema which defines the cgMLST schema. The cgMLST schema consists of 2,406 loci and has been defined as the loci present in at least the 99% of the 331<em> [...]
Vers les cellules solaires à haut rendement à base de composés III-V sur substrats bas-couts de silicium
International audienc
Advanced concepts of photovoltaics based on III-V compounds
With 25.6% conversion efficiency, solar cells based on the c-Si generation reach their limits. Ho... more With 25.6% conversion efficiency, solar cells based on the c-Si generation reach their limits. However, the third generation solar cells, such as multijunction solar cells and hot-carrier solar cells (HCSCs), allow to overcome the intrinsic limit of a single junction. Firstly, we show the first stage developments of a GaAsPN/Si tandem cell on Si, which benefit from the low cost and technological maturity of Si cells. The GaAsPN dilute-nitride compound, grown by MBE, is quasi lattice-matched with Si, and displays the required the required 1.7 eV pseudo-bandgap. Secondly, HCSCs aim to reduce the thermalization process which is a major loss in a classical PV cells. This can be done by the reduction of the electron-phonons interactions in quantum wells (QWs) structures. Therefore, we have investigated a InGaAsP multi-QWs heterostructure epitaxially grown on a InP(001) substrate and demonstrate its potential to work as a hot carrier cell absorber. Finally, some outstanding properties of ...
Toward the III-V/Si high efficiency tandem solar cell
International audienc
Towards the III-V/Si CPV on Si substrates
International audienc
Parasitoses em ribeirinhos do Trombetas
Trabalho apresentado no Congresso da Sociedade Brasileira de Medicina Tropical, 37., 2001, Salvador.
A ce jour, les meilleurs rendements de conversion photovoltaique ont ete obtenus avec des cellule... more A ce jour, les meilleurs rendements de conversion photovoltaique ont ete obtenus avec des cellules solaires multi-jonctions a base de materiaux semi-conducteurs III-V monocristallins sous eclairement solaire concentre. Cependant, le recours aux substrats III-V dans la fabrication de cellules solaires a haut rendement pose le probleme des couts consequents de ces materiaux. Afin de relever le defi strategique d’un cout de 0.25-0.5 Euro/Wp, nous avons opte pour l’utilisation du substrat silicium, qui est tres abondant sur Terre et donc bon marche. L’integration monolithique d’heterostructures III-V sur silicium permettrait de concilier a la fois hauts rendements et bas couts, tout en capitalisant sur une filiere industrielle eprouvee. Nous explorons deux approches de cellules III-V sur Silicium : les cellules tandem et les heterojonctions. Une cellule solaire tandem, constituee d’une cellule III-V a 1.7 eV sur une cellule c-Si a 1.1 eV, permettrait theoriquement d’atteindre 37% de ren...
GaAsPN Absorbers Grown on GaP for Multijunction Solar Cells: Optical Absorption and Thermal Conductivity Properties
Optical absorption and thermal conductivity of GaAsPN absorbers grown on GaP are investigated by ... more Optical absorption and thermal conductivity of GaAsPN absorbers grown on GaP are investigated by optical absorption spectroscopy and photo‐thermal deflection spectroscopy (PDS). First, the strong dependence of optical absorption on As content is shown: with a maximum absorption coefficient of 38,000 cm‐1 below the GaP bandgap. Optical absorption and thermal conductivity of the samples are then evaluated for various growth and annealing conditions using PDS. The significantly positive impact of annealing on both properties is demonstrated. Thermal conductivity reached 4W/mK for the best sample. These results are promising for the development of absorbers in multijunction solar cells.
Numerical and experimental ongoing on III-V/Si high-efficiency tandem solar cell
International audienc
First stage results on III-V/Si tandem cells using GaAsPN dilute-nitride
International audienc
PI3Kγ/AKT1 signaling in macrophages is essential for resistance against Trypanosoma cruzi infection
Nowadays, due to major technological developments, specifically in the area of multifunctional mo... more Nowadays, due to major technological developments, specifically in the area of multifunctional mobile devices, it is unthinkable not to imagine the evolution of smart home middlewares to integrate such kind of equipment, as it will provide users with an excellent integration of several services under a stunning user interface. In addition to this evolution, the use of a smartphone’s sensory capabilities can improve and innovate the way the user interacts with his home. This work aims to continue the middleware iDASH [1], which allows the creation of an abstraction layer, expanding it to mobile platforms, specifically equipments developed by Apple. Additionally, it enables the possibility of using smartphone sensors to trigger certain events in the context of smart home, as well as the ability to interact remotely in the context of a smart home. This can improve significantly the convenience and user’s satisfaction.
The following report begins with a brief historical overview of the Coimbra University Press and ... more The following report begins with a brief historical overview of the Coimbra University Press and follows with the description of the activities I accomplished during the internship. The various activities I carried out in the Coimbra University Press are then described, namely text revision and normalization, elaborating manuals, promotion through electronical means, diagramming, conducting various analyses and studies and other activities. Finally, some general considerations about the role of social networks as a support to publishing are presented, backed by published books.
GaAsPN Single and Tandem Solar Cells on Silicon
The development of a III‐V on silicon tandem cell is reported. GaAsPN material is considered for ... more The development of a III‐V on silicon tandem cell is reported. GaAsPN material is considered for top cell absorber because of its quasi‐lattice matching with silicon and its pseudo‐direct bandgap at 1.7 eV. First, GaAsPN single cells are grown on both GaP and Si substrates, and their electrical performances are compared. It is found that the performances of the cell are limited by the low carrier mobility induced by the use of dilute nitrides. Then the first‐stage development of a tandem photovoltaic solar cell is reported, including a tunnel junction (TJ) made of Si.
In)GaP integration on Si for photonics and energy
International audienc
GaP/Si-Based Photovoltaic Devices Grown by Molecular Beam Epitaxy
Molecular Beam Epitaxy, 2018
Here, we discuss the recent developments toward efficient GaP/Si-based photovoltaic devices and t... more Here, we discuss the recent developments toward efficient GaP/Si-based photovoltaic devices and their implementation using Molecular Beam Epitaxy. The GaP/Si structural and electronic characteristics are first presented with respect to PV applications. It is shown that the presence of antiphase boundaries deeply impact both structural and electronic properties. Issues related to GaP processing are then discussed. Performances of GaP-based PV single solar cells and GaP/Si-based tandem solar cells are reviewed. While performances of photovoltaic devices are encouraging, they are still far from the theoretical limit achievable and require additional materials research. To this aim, molecular beam epitaxial techniques provide many advantages. Finally, we report on the last development of GaP/Si heterojunctions, which has the theoretical ability to surpass the efficiency of the a-Si/c-Si heterojunctions due to the higher GaP bandgap as compared to the a-Si.
Anais de XXXV Simpósio Brasileiro de Telecomunicações e Processamento de Sinais, 2017
Resumo Este artigo analisa, através de processamento de sinais, a interação entre densidade de fl... more Resumo Este artigo analisa, através de processamento de sinais, a interação entre densidade de fluxo magnético e um material submetido a diferentes condições de tratamento. O objetivo é estudar o ruído gerado dessa interação e correlacionálo com o grau de fragilização do material. Um aço inoxidável duplex SAF 2205 é utilizado. Os sinais são analisados através de FFT e correlacionados com valores de energia absorvida por impacto. Os resultados mostram que as distribuições de frequências dos sinais de FFT acompanham a formação da fase que fragiliza o material e que os valores médios das amplitudes de frequências servem como parâmetro de monitoramento.
Detection of microstructure anisotropy using induced magnetic fields
Procceedings of the 24th ABCM International Congress of Mechanical Engineering, 2017
Detection of ferrite phase transformation by induced magnetic field on a duplex stainless steel
Procceedings of the 24th ABCM International Congress of Mechanical Engineering, 2017
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Papers by mickael da silva