A single-phase current-source converter combined with a hybrid converter for interfacing an electric vehicle and a renewable energy source

This paper presents a single-phase current-source converter (CSC) combined with a hybrid converter on the dc-link, allowing to interface an electric vehicle (EV) and a renewable energy source (RES). Therefore, the interface with the power grid is only performed through the CSC, which also permits the operation as shunt active power filter (SAPF), allowing to compensate power quality problems related with current and low power factor in the electrical installation. The whole system is composed by two main power stages, namely, the CSC that is responsible for compensating the current harmonics and low power factor, as well as operating as a grid-tied inverter or as an active rectifier, and the hybrid converter that is responsible for interfacing the dc-link of the CSC with the converters for the EV and the RES interfaces. As demonstrated along the paper, the CSC, combined with the hybrid converter on the dc-link, allows the operation as SAPF, as well as the operation in bidirectional mode, specifically for the EV operation, and also for injecting power from the RES. In the paper, the power electronics structure is described and the principle of operation is introduced, supported by the description of the control algorithms. The validation results show the proper operation of the CSC, combined with the hybrid converter on the dc-link, for the main conditions of operation, namely exchanging power with the power grid in bidirectional mode and operating as a SAPF.This work has been supported by FCT – Fundação para a Ciência e Tecnologia with-in the Project Scope: UIDB/00319/2020. This work has been supported by the FCT Project newERA4GRIDs PTDC/EEI-EEE/30283/2017 and the FCT Project DAIPESEV PTDC/EEI-EEE/30382/2017

Clean-Room lithographical processes for the fabrication of Graphene biosensors

This work is on developing clean-room processes for the fabrication of electrolyte-gate graphene field-effect transistors at the wafer scale for biosensing applications. Our fabrication process overcomes two main issues: removing surface residues after graphene patterning and the dielectric passivation of metallic contacts. A graphene residue-free transfer process is achieved by using a pre-transfer, sacrificial metallic mask that protects the entire wafer except the areas around the channel, source, and drain, onto which the graphene film is transferred and later patterned. After the dissolution of the mask, clean gate electrodes are obtained. The multilayer SiO2/SiNx dielectric passivation takes advantage of the excellent adhesion of SiO2 to graphene and the substrate materials and the superior impermeability of SiNx. It hinders native nucleation centers and breaks the propagation of defects through the layers, protecting from prolonged exposition to all common solvents found in biochemistry work, contrary to commonly used polymeric passivation. Since wet etch does not allow the required level of control over the lithographic process, a reactive ion etching process using a sacrificial metallic stopping layer is developed and used for patterning the passivation layer. The process achieves devices with high reproducibility at the wafer scale.Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UIDB/04650/2020, UIDP/00013/2020, and Operational Program Competitiveness and Internationalization (POCI) under project POCI-01-0145-FEDER-031069 (PORTGRAPHE). This work was partially supported by E.U. Horizon 2020 Research and Innovation Programme, under project MULTIMAL (grant #777222). P.D. Cabral acknowledges the Ph.D. grant (SFRH/BD/128579/2017) from the FC

Design, Characterization and Biological Properties

Funding Information: This work was financed by national funds from FCT—Fundação para a Ciência e a Tecnologia, I.P., in the scope of projects UIDP/04378/2020 and UIDB/04378/2020 of the Research Unit on Applied Molecular Biosciences—UCIBIO, the project LA/P/0140/2020 of the Associate Laboratory Institute for Health and Bioeconomy—i4HB, project UIDP/04129/2020 of LEAF—Linking Landscape, Environment, Agriculture and Food—Research Center, and projects LA/P/0037/2020, UIDP/50025/2020 and UIDB/50025/2020 of the Associate Laboratory Institute of Nanostructures, Nanomodelling and Nanofabrication—i3N. Diana Araújo and Catarina Roma-Rodrigues were funded by FCT/MCTES, with grant numbers SFRH/BD/140829/2018 and SFRH/BPD/124612/2016, respectively. Publisher Copyright: © 2023 by the authors.FucoPol, a fucose-rich polyanionic polysaccharide, was used for the first time for the preparation of hydrogel membranes (HMs) using Fe3+ as a crosslinking agent. This study evaluated the impact of Fe3+ and FucoPol concentrations on the HMs’ strength. The results show that, above 1.5 g/L, Fe3+ concentration had a limited influence on the HMs’ strength, and varying the FucoPol concentration had a more significant effect. Three different FucoPol concentrations (1.0, 1.75 and 2.5 wt.%) were combined with Fe3+ (1.5 g/L), resulting in HMs with a water content above 97 wt.% and an Fe3+ content up to 0.16 wt.%. HMs with lower FucoPol content exhibited a denser porous microstructure as the polymer concentration increased. Moreover, the low polymer content HM presented the highest swelling ratio (22.3 ± 1.8 g/g) and a lower hardness value (32.4 ± 5.8 kPa). However, improved mechanical properties (221.9 ± 10.2 kPa) along with a decrease in the swelling ratio (11.9 ± 1.6 g/g) were obtained for HMs with a higher polymer content. Furthermore, all HMs were non-cytotoxic and revealed anti-inflammatory activity. The incorporation of FucoPol as a structuring agent and bioactive ingredient in the development of HMs opens up new possibilities for its use in tissue engineering, drug delivery and wound care management.publishersversionpublishe

Enhanced three-phase shunt active power filter interfacing a renewable and an energy storage system

This paper presents an enhanced three-phase shunt active power filter (SAPF) that, besides its inherent functionalities of power quality problems compensation, also allows the interface of a renewable energy source (RES, namely solar photovoltaic – PV panels) and an energy storage system (ESS, namely batteries) through its dc-link. On the power grid-side, a three-phase four-wire voltage-source ac-dc converter is connected with the power grid, operating as an SAPF, whereas the RES-interface and the ESS-interface are made through a three-port multilevel dc-dc converter connected to the dc-link of the SAPF. Besides, to compensate power quality problems related to currents, the SAPF also permits the controllability of the bidirectional power exchanged between the power grid and the dc interfaces, i.e., the RES and the ESS. The operation principle of the whole system, as well as the detailed control algorithms, are described in the paper. A validation was performed through computer simulations, where it is possible to analyze the different operation modes of the enhanced SAPF interfacing a RES and an ESS through the dc-link.This work has been supported by FCT – Fundação para a Ciência e Tecnologia within the R&D Units Project Scope: UIDB/00319/2020. This work has been supported by the FCT Project newERA4GRIDs PTDC/EEI-EEE/30283/2017. Tiago J. C. Sousa is supported by the doctoral scholarship SFRH/BD/134353/2017 granted by FCT

Predictive equations of pulmonar function for healthy children in Portugal

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Experimental analysis of niti alloy during strain-controlled low-cycle fatigue

PTDC/CTM-CTM/29101/2017- POCI-01-0145-FEDER-029101 UIDB/EMS/00285/2020 UIDB/50025/2020-2023The interaction between the stress-induced martensitic transformation and resistivity behavior of superelastic NiTi shape memory alloy (SMA) was studied. Strain-controlled low-cycle fatigue up to 6% was monitored by in situ electrical resistivity measurements. The experimental results show that a great motion of martensite fronts results in a significant accumulation of defects, as evidenced by transmission electron microscopy (TEM), before and after the tensile cycles. This gives rise to an overall increase of the resistivity values up to the maximum deformation. Therefore, the research suggests that shape memory alloy wire has great potential as a stress sensor inside bulk materials.publishersversionpublishe

sensitivity analysis

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Swimming and risk of asthma and allergies in Portuguese school aged children

[resumo][abstract

Accidental Jorge Lobo's disease in a worker dealing with Lacazia loboi infected mice: a case report

<p>Abstract</p> <p>Introduction</p> <p>Jorge Lobo's disease (Lacaziosis) is a subcutaneous infection of humans living in the Amazon region of Latin America, and in dolphins inhabiting the east coastal areas of the United States. The disease mainly affects people from rural areas living or working in close contact with vegetation and aquatic environments. Most patients refer having developed lesions after accidental trauma with plant thorns or insect bites. Inter-human transmission has never been confirmed suggesting that <it>Lacazia loboi </it>is acquired from environmental propagules.</p> <p>Case presentation</p> <p>We report the case of a 41-year-old woman from São Paulo, Brazil, a non-endemic area of Jorge Lobo's disease, with <it>L. loboi </it>skin infection most likely accidentally acquired while manipulating experimentally infected mice in the laboratory.</p> <p>Conclusion</p> <p>Because many patients with Jorge Lobo's disease do not recall accidental skin trauma before their infections, the possibility of accidentally acquired Jorge Lobo's disease through unnoticed broken skin should be considered during the clinical investigation of nodular skin diseases in people who have contact with the fungus or who live in endemic areas. This is the second report of animal to human transmission of this disease.</p