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Screening for microplastics in agricultural soils: Applying green chemistry pri...
Rede, Diana; Vilarinho, Rui; Delerue-Matos, Cristina; Moreira, Joaquim Agostinho; Fernandes, Virgínia Cruz; Fernandes, VirgíniaIn recent years, microplastic (MP) pollution has garnered significant attention owing to its ability to permeate various ecosystems, including soil. These particles can infiltrate the environment, either directly or through the degradation of larger plastic items. Despite growing concerns, standardized methods for quantification are still lacking. This study aimed to screen for the presence of MPs in agricultur...
Deciphering zebrafish spectral signatures: insights from Raman spectroscopy
Oliveira Abreu, Isabel; Teixeira, Cláudia; Vilarinho, Rui; S. Rocha, A. Cristina; Moreira, Joaquim Agostinho; Oliva-Teles, Luís; Guimarães, LauraBackground: Raman spectroscopy (RS) is a sensitive technique used for gathering chemical and molecular data, resulting in a biochemical fingerprint of the sample. This method is label-free and provides rapid detection [1]. Furthermore, it has proven invaluable in the forensic, biological and medical contexts [2]. It is also suitable for investigations assessing toxic effects of some chemicals, enablin...
Electrical properties of polypropylene-based composites melt-processed with as-...
Paleo, Antonio J.; Samir, Zineb; Aribou, Najoia; Nioua, Yassine; Moreira, Joaquim Agostinho; Achour, Mohammed EssaidElectrical conductivity, dielectric permittivity, electrical modulus, and electrical impedance of polypropylene (PP) composites melt-processed with different contents of as-grown carbon nanofibers (CNFs) are studied. As expected, the electrical conductivity of PP/CNF composites increased as the incorporation of CNFs is raised in the polymer, yielding a maximum of ∼ 6 ×10−6 S m−1 for PP/CNF 3 wt. % composites. T...
Dielectric spectroscopy of melt-mixed polypropylene and pyrolytically stripped ...
Samir, Zineb; Paleo, Antonio J.; Aribou, Najoia; Nioua, Yassine; Silva, Jaime Oliveira da; Cerqueira, M. F.; Moreira, Joaquim AgostinhoIn this work, pyrolytically stripped carbon nanofiber (CNF) polypropylene (PP) composites were synthesized following a scalable melt-mixing method, and the effects of CNF weight concentrations on the electrical conductivity, dielectric permittivity, electrical modulus and electrical impedance of PP/CNF composites were studied. Quite unexpectedly, the electrical conductivity of PP/CNF composites improved only sl...
Touch sensor and photovoltaic characteristics of CuSbS2 thin films
Chlibi, Nadia; Silva, José Pedro Basto; Vieira, E. M. F; Gonçalves, L. M.; Moreira, Joaquim Agostinho; Chahboun, Adil; Dahman, Hassen; Pereira, MárioSpin-coated chalcostibite CuSbS2 thin films (≈500 nm thick) were fabricated and the influence of the drying temperature on the structural, morphological, optical and thermoelectric properties of the films was investigated. Crystalline phase-pure chalcostibite has been obtained for the films dried at 180 ◦C and 210 ◦C, while below 180 ◦C these films are partially amorphous. Surprisingly, at drying temperature of...
HfO2–Al2O3 Dielectric Layer for a Performing Metal–Ferroelectric–Insulator–Semi...
Silva, José Pedro Basto; Sekhar, Koppole C.; Veltruská, Katerina; Matolín, Vladimir; Negrea, Raluca F.; Ghica, Corneliu; Oliveira, Marcelo José SilvaIn this work, the ferroelectric and fatigue characteristics of Au/0.5Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3(BCZT)/Si metal–ferroelectric–semiconductor (MFS) structures are investigated. Moreover, the effect of introducing a thin dielectric HfO2–Al2O3 (HAO) layer with different thicknesses between the BCZT layer and the Si substrate on the ferroelectric characteristics in the metal–ferroelectric–insulator–semicond...