21 documents found, page 1 of 3
Tailored cellulose-based flocculants for microplastics removal: mechanistic ins...
Magalhães, Solange; Norgren, Magnus; Alves, Luís; Medronho, Bruno; Rasteiro, Maria da GraçaThis study explores the performance of novel cellulose-derived sustainable flocculants in the flocculation of different model microplastics (MPs), including polyethylene (PE), polyethylene terephthalate (PET) and polyvinyl chloride (PVC). The influence of key parameters, such as pH, flocculant structure and concentration was evaluated by Laser Diffraction Spectroscopy (LDS) and optical microscopy to access thei...
Insights on microplastic contamination from municipal and textile industry effl...
Magalhães, Solange; Paciência, Daniel; Rodrigues, João M. M.; Lindman, Björn; Alves, Luís; Medronho, Bruno; Rasteiro, Maria da GraçaThe rampant use of plastics, with the potential to degrade into insidious microplastics (MPs), poses a significant threat by contaminating aquatic environments. In the present study, we delved into the analysis of effluents from textile industries, a recognized major source of MPs contamination. Data were further discussed and compared with a municipal wastewater treatment plant (WWTP) effluent. All effluent sa...
Enhancing cellulose and lignin fractionation from acacia wood: optimized parame...
Magalhães, Solange; Aliaño González, María José; Rodrigues, Mariana; Fernandes, Catarina; Mendes, Cátia V. T.; Carvalho, Maria Graça V. S.; Alves, LuísCellulose and lignin, sourced from biomass, hold potential for innovative bioprocesses and biomaterials. However, traditional fractionation and purification methods often rely on harmful chemicals and high temperatures, making these processes both hazardous and costly. This study introduces a sustainable approach for fractionating acacia wood, focusing on both cellulose and lignin extraction using a deep eutect...
Isolation of Extracellular Vesicles from Human Follicular Fluid: Size-Exclusion...
Soares, Maria; Pinto, Maria M.; Nobre, Rui J.; Almeida, Luís Pereira de; Rasteiro, Maria da Graça; Santos, Teresa Almeida; Santos, João RamalhoFollicular fluid (FF) is the microenvironment where a growing oocyte develops. Intrafollicular communication ensures oocyte competence and is carried out through paracrine signaling, the exchange of molecules via gap junctions, and the trafficking of extracellular vesicles (EVs). The study of FF-derived EVs is important for both translational and fundamental research in the female reproductive field. This study...
On Hair Care Physicochemistry: From Structure and Degradation to Novel Biobased...
Fernandes, Catarina; Medronho, Bruno; Alves, Luís; Rasteiro, Maria da GraçaHair is constantly exposed to various adverse external stimuli, such as mechanical or thermal factors, that may cause damage or cause it to lose its shine and smooth appearance. These undesirable effects can be minimized by using hair conditioners, which repair the hair and restore the smooth effect desired by the consumer. Some of the currently used conditioning agents present low biodegradability and high tox...
Anionic bio-flocculants from sugarcane for purification of sucrose: An applicat...
Leão, Sofia; Magalhães, Solange; Alves, Luís; Gamelas, José A. F.; Lima, Claudio; Stein, Bruno; Rasteiro, Maria da GraçaIn sugar production, polyacrylamide-based anionic flocculants are added for juice treatment, the main objective being to remove impurities that affect the quality of the sugar. However, if they remain in the final product, those polymers can present carcinogenic and neurotoxic actions besides contaminating the soils where the waste is discharged. To overcome this problem, the present study proposes, for the fir...
An Experimental Design Methodology to Evaluate the Key Parameters on Dispersion...
Correia, António Alberto S.; Figueiredo, Diogo; Rasteiro, Maria da GraçaThe incorporation of carbon nanotubes (CNTs) in the process of chemical stabilization of soft soil is only possible when they are dispersed adequately in the medium. The maximum compressive strength (qu max) and the secant undrained Young’s modulus (Eu 50) are usually used to characterize the behavior of soil stabilized with Portland cement. In the present study, soft soil was additivated with a CNT dispersion ...
Computational Fluid Dynamic Modelling of Fully-Suspended Slurry Flows in Horizo...
Messa, Gianandrea Vittorio; Yang, Qi; Rasteiro, Maria da Graça; Faia, Pedro M.; Matoušek, Vaclav; Silva, Rui C.; Garcia, FernandoThis research work is a significant step toward further understanding of the β-σ two-fluid model for the simulation of fully-suspended slurry flows in pipeline systems, with the goal of enhancing its potential for scientific research and engineering applications. Particularly, the focus of the study is the characterization and handling of the two main empirical coefficients of the model, namely, β and σ, which ...
Eco-friendly Methods for Extraction and Modification of Cellulose: An Overview
Magalhães, Solange; Fernandes, Catarina; Pedrosa, Jorge F. S.; Alves, Luís; Medronho, Bruno; Ferreira, Paulo J.; Rasteiro, Maria da GraçaCellulose is the most abundant renewable polymer on Earth and can be obtained from several different sources, such as trees, grass, or biomass residues. However, one of the issues is that not all the fractionation processes are eco-friendly and are essentially based on cooking the lignocellulose feedstock in a harsh chemical mixture, such as NaOH + Na2S, and water, to break loose fibers. In the last few years, ...
Influence of dispersion of fibrillated cellulose on the reinforcement of coated...
Sanchez-Salvador, Jose Luis; Rasteiro, Maria da Graça; Balea, Ana; Sharma, Mohit; Pedrosa, Jorge F. S.; Negro, Carlos; Monte, M ConcepcionThe use of cellulose micro/nanofibrils (CMNFs) as reinforcement paper additive at industrial scale is delayed due to inconsistent results, suggesting a lack of proper consideration of some key parameters. The high influence of fibrillated nanocellulose dispersion has been recently identified as a key parameter for paper bulk reinforcement but it has not been studied for surface coating applications yet. This pa...