12 documents found, page 1 of 2
Markerless three-dimensional gait analysis in healthy older adults: test–retest...
Carvalho, Andreia; Vanrenterghem, Jos; Cabral, Sílvia; Assunção, Ana; Fernandes, Rita; Veloso, António P.; Moniz-Pereira, VeraIn older adults, gait analysis may detect changes that signal early disease states, yet challenges in biomechanical screening limit widespread use in clinical or community settings. Recently, a markerless method from multi-camera video data has become accessible, making screenings less challenging. This study evaluated the test-retest reliability and measurement error of markerless gait kinematics and kinetics ...
N,N '-dimethyl-N,N '-dicyclohexylsuccinamide: a novel molecule for the separati...
Costa, M. Clara; Assunção, Ana; Almeida, Ruben; Costa, Ana M. Rosa da; Nogueira, Carlos; Paiva, A. P.ABSTRACT: N,N'-dimethyl-N,N'-dicyclohexylsuccinamide (DMDCHSA) is investigated as a potential molecule for the liquid-liquid extraction of Pd(II) from chloride solutions for the first time. The effect of several parameters on Pd(II) extraction, such as the contact period between both phases, hydrochloric acid, extractant and hydrogen ion concentrations, is evaluated. Pd(II) extraction equilibrium is very fast (...
N,N '-dimethyl-N,N '-dicyclohexylsuccinamide: A novel molecule for the separati...
Costa, Maria Clara; Assunção, Ana; Almeida, Rúben; Rosa da Costa, Ana; Nogueira, Carlos; Paiva, Ana PaulaN,N'-dimethyl-N,N'-dicyclohexylsuccinamide (DMDCHSA) is investigated as a potential molecule for the liquid-liquid extraction of Pd(II) from chloride solutions for the first time. The effect of several parameters on Pd(II) extraction, such as the contact period between both phases, hydrochloric acid, extractant and hydrogen ion concentrations, is evaluated. Pd(II) extraction equilibrium is very fast (30 s) and ...
A bridge between liquid-liquid extraction and the use of bacterial communities ...
Assunção, Ana; Matos, Ana; Costa, Ana M. Rosa da; Candeias, Antonio; Costa, Maria ClaraThe Platinum Group Metals (PGM) are rare in the Earth's crust and in the past years their use had a considerable expansion limiting their availability, which justifies PGM's high commercial value and demand. Therefore, PGM recovery from secondary sources is very important from both economic and environmental points of view. In recent years, several methods for PGM removal have been investigated. Our research gr...
Biological and chemical strategies for the recovery of precious and rare metals...
Assunção, AnaThe present work explored the potential of chemical (solvent extraction) and biological (using anaerobic bacterial community) technologies, aiming the removal/recovery of precious metals from aqueous solutions. Solvent extraction or liquid-liquid extraction was used to find a suitable platinum and palladium extractant, to be applied to the treatment of aqueous solutions containing these metals. Thus, N,N’-dimet...
Performance and bacterial community shifts during phosphogypsum biotransformation
Martins, Mónica; Assunção, Ana; Neto, André; Silva, Gonçalo; Sghaier, Haitham; Costa, Maria ClaraPhosphogypsum (PG) is an industrial waste composed mainly by sulfate, turning it a suitable sulfate source for sulfate-reducing bacteria (SRB). In the present work, the capability of two SRB communities, one enriched from Portuguese PG (culture PG) and the other from sludge from a wastewater treatment plant (culture WWT-1), to use sulfate from PG was compared. In addition, the impact of this sulfate-rich waste ...
Application of urea-agarose gel electrophoresis to select non-redundant 16S rRN...
Assunção, Ana; Costa, Maria Clara; Carlier, JorgeThe 16S ribosomal RNA (rRNA) gene has been the most commonly used sequence to characterize bacterial communities. The classical approach to obtain gene sequences to study bacterial diversity implies cloning amplicons, selecting clones, and Sanger sequencing cloned fragments. A more recent approach is direct sequencing of millions of genes using massive parallel technologies, allowing a large-scale biodiversity ...
N,N′-tetrasubstituted succinamides as new molecules for liquid–liquid extractio...
Costa, Maria Clara; Almeida, Ruben; Assunção, Ana; Costa, Ana M. Rosa da; Nogueira, Carlos; Paiva, Ana PaulaDue to the increasing demand of platinum group metals (PGM’s), among which platinum, the search for new alternatives aiming to their extraction and recovery is nowadays of great importance. Thus, two N, N0-tetrasubstituted succinamides, N,N0-dicyclohexyl-N,N0-dimethylsuccinamide (DMDCHSA) and N,N0- dimethyl-N,N0-diphenylsuccinamide (DMDPHSA) were synthesized and investigated, for the first time, as potential mo...
Recovery of gold(0) nanoparticles from aqueous solutions using effluents from a...
Assunção, Ana; Vieira, Bernardete; Lourenço, J. P.; Costa, Maria ClaraThe use of biological processes with the aim of the recovery of gold from low-concentration solutions derived from leaching of secondary sources is gaining increasing importance owing to the scarcity of the primary resources and the economic and environmental advantages usually presented by these methods. Thus, the addition in batch and continuous processes of different solutions containing biogenic sulphide, w...
Liquid-Liquid Extraction of Platinum from Chloride Media by N,N'-Dimethyl-N,N'-...
Costa, M. Clara; Assunção, Ana; Costa, Ana M. Rosa da; Nogueira, Carlos; Paiva, A. P.Liquid-liquid extraction of platinum(IV) from chloride media was carried out using N,N'-dimethyl-N,N'-dicyclohexyltetradecylmalonamide (DMDCHTDMA) in 1,2-dichloroethane. Platinum can be effectively extracted by DMDCHTDMA without addition of tin(II) chloride, since extraction percentages (%E) of 88% and 99% have been achieved from 6 M and 8 M HCl, respectively. Moreover, platinum can be successfully stripped thr...