118 documents found, page 1 of 12
Microfabrication of rubidium-85 vapor cell for optically pumped magnetometer ap...
Pereira, Hugo Martins; Dores, B. S.; Silva, J. P. O.; Venâncio, Armando; Cerqueira, M. F.; Rodrigues, J. A.; Correia, J. H.Neuroimaging methods have contributed to enhancing the knowledge of human brain activity. Magnetoencephalography is a general neuroimaging method that typically uses superconducting quantum interference devices as brain magnetic field sensors that require cryogenic cooling, putting practical and economical limitations. Optically pumped magnetometers are a promising alternative based on the use of atomic vapor c...
Raman spectroscopy for classification of neoplastic and non-neoplastic CAM colo...
Esteves, Bruno Miguel Carpinteiro; Pimenta, Sara Filomena Ribeiro; Maciel, Marino Jesus Correia; Costa, Marta Sílvia Freitas; Baltazar, FátimaThis paper demonstrates the potential of Raman spectroscopy for differentiating neoplastic from non-neoplastic colon tumors, obtained with the CAM (chicken chorioallantoic membrane) model. For the CAM model two human cell lines were used to generate two types of tumors, the RKO cell line for neoplastic colon tumors and the NCM460 cell line for non-neoplastic colon tumors. The Raman spectra were acquired with a ...
Development and production of a CNC machined 420 stainless steel reinforced wit...
Cunha, A.; Pinto, J.; Cerqueira, M. F.; Silva, F. S.; Trindade, B.; Carvalho, O.Multi-material structures make it possible to obtain effective solutions to engineering problems by combining the benefits of different materials to meet the requirements of different working conditions. The aim of this multifunctional 420 stainless steel-copper structure is to create a hybrid solution in which copper acts as heat-transfer enhancer (through cooling channels) while maintaining the required mecha...
Comparative thermoelectric properties of polypropylene composites melt-processe...
Paleo, Antonio J.; Krause, Beate; Mendes, Ana R.; Tavares, C. J.; Cerqueira, M. F.; Muñoz, Enrique; Pötschke, PetraThe electrical conductivity (σ) and Seebeck coefficient (S) at temperatures from 40 ◦C to 100 ◦C of melt-processed polypropylene (PP) composites filled with 5 wt.% of industrial-grade carbon nanofibers (CNFs) is investigated. Transmission Electron Microscopy (TEM) of the two Pyrograf® III CNFs (PR 19 LHT XT and PR 24 LHT XT), used in the fabrication of the PP/CNF composites (PP/CNF 19 and PP/CNF 24), reveals th...
Electronic features of cotton fabric e-textiles prepared with aqueous carbon na...
Paleo, Antonio J.; Krause, Beate; Cerqueira, M. F.; Muñoz, Enrique; Pötschke, Petra; Rocha, A. M.Cotton woven fabrics functionalized with aqueous inks made with carbon nanofibers (CNFs) and anionic surfactant are prepared via dip-coating followed by heat treatment, and their electronic properties are discussed. The e-textiles prepared with the inks made with the highest amount of CNFs (6.4 mg mL−1 ) show electrical conductivities (σ) of ∼35 S m−1 and a negative Seebeck (S) of −6 μV K−1 at 30 °C, which mean...
Combining x-ray real and reciprocal space mapping techniques to explore the epi...
Magalhaes, S.; Cabaco, J. S.; Concepcion, O.; Buca, D.; Stachowicz, M.; Oliveira, F.; Cerqueira, M. F.; Lorenz, K.; Alves, E.In the present work, the importance of determining the strain states of semiconductor compounds with high accuracy is demonstrated. For the matter in question, new software titled LAPAs, the acronym for LAttice PArameters is presented. The lattice parameters as well as the chemical composition of Al1-xInxN and Ge1-xSnx compounds grown on top of GaN- and Ge-buffered c-Al2O3 and (001) oriented Si substrates, resp...
Development and production of a CNC machined 420 stainless steel reinforced wit...
Cunha, A.; Pinto, J.; Cerqueira, M. F.; Silva, Filipe Samuel; Trindade, B.; Carvalho, O.Multi-material structures make it possible to obtain effective solutions to engineering problems by combining the benefits of different materials to meet the requirements of different working conditions. The aim of this multifunctional 420 stainless steel-copper structure is to create a hybrid solution in which copper acts as heat-transfer enhancer (through cooling channels) while maintaining the required mecha...
The role of hydrogen incorporation into amorphous carbon films in the change of...
Bundaleski, Nenad; Adame, Carolina F.; Alves, Eduardo; Barradas, Nuno P.; Cerqueira, M. F.; Deuermeier, Jonas; Delaup, Yorick; Ferraria, Ana M.Over the last few years, there has been increasing interest in the use of amorphous carbon thin films with low secondary electron yield (SEY) to mitigate electron multipacting in particle accelerators and RF devices. Previous works found that the SEY increases with the amount of incorporated hydrogen and correlates with the Tauc gap. In this work, we analyse films produced by magnetron sputtering with different...
Multi-material Inconel 718 parts with highly conductive copper cooling channels...
Marques, Ana; Guimarães, Bruno; Cerqueira, M. F.; Silva, Filipe Samuel; Carvalho, OscarMulti-material parts can offer valuable solutions to engineering problems when compared to single materials. The conceptualization of a multifunctional Inconel 718 (IN718)–Copper (Cu) solution aims to improve the heat extraction capacity of an aerospace component. High-strength IN718 was used as the base material and highly thermal conductive Cu was employed for internal cooling channels. The cooling channels a...
Nonlinear thermopower behaviour of n-type carbon nanofibres and their melt mixe...
Vieito, António Jose Paleo; Krause, Beate; Cerqueira, M. F.; Muñoz, Enrique; Pötschke, Petra; Rocha, A. M.The temperature dependent electrical conductivity <i>σ</i> (<i>T</i>) and thermopower (Seebeck coefficient) <i>S</i> (<i>T</i>) from 303.15 K (30 °C) to 373.15 K (100 °C) of an as-received commercial n-type vapour grown carbon nanofibre (CNF) powder and its melt-mixed polypropylene (PP) composite with 5 wt.% of CNFs have been analysed. At 30 °C, the <i>σ</i> and <i>S</i> of the CNF powder are ~136 S m<sup>−1</s...