15 documents found, page 1 of 2
Physicochemical Characterisation of Olive Mill Wastewaters Based on Extraction ...
Afonso, Inês Santos; Duarte, Cristina; Afonso, Maria João A.P.S.; Ribeiro, António E.; Amaral, Joana S.; Sousa, Patrícia C.; Lima, Rui A.Olive mill wastewaters (OMWW) generated during olive oil extraction represent a significant environmental challenge due to their high organic matter content, acidic pH, phenolic content, and toxicity. Their composition varies widely depending on the extraction method and remains difficult to treat, particularly for small-scale producers lacking access to complex infrastructure. This study evaluates the combined...
Progress in Nanofluid Technology: From Conventional to Green Nanofluids for Bio...
Cardoso, Beatriz D.; Souza, Andrews; Nobrega, Glauco; Afonso, Inês Santos; Neves, Lucas Boniatti; Faria, Carlos; Ribeiro, J.E.; Lima, Rui A.Nanofluids (NFs), consisting of nanoparticles (NPs) suspended in base fluids, have attracted growing interest due to their superior physicochemical properties and multifunctional potential. In this review, conventional and green NF technology aspects, including synthesis routes, formulation, and applications, are discussed. Conventional NFs, involving NPs synthesized using physical and chemical approaches, have...
Thermal performance evaluation of pure PDMS and PDMS composites heat exchangers
Souza, Reinaldo; Nobrega, Glauco; Afonso, Inês Santos; Pereira, José; Cardoso, Elaine; Marques, Filipe; Vilarinho, Cândida; Moita, Ana; Lima, Rui A.This study investigates the heat transfer performance of three types of heat exchangers: one made of pure polydimethylsiloxane (PDMS), another incorporating recycled graphite (PDMS + Graphite 30 mass%), and a third using commercial aluminium nanoparticles (PDMS + Aluminium 30 mass%). Thermal performance was evaluated by measuring the thermal conductivity of the materials, analysing experimental convection tests...
Exploring heat exchange in space: Recent advances in two-phase fluid experiment...
Nobrega, Glauco Tapijara Vallicelli; Afonso, Inês Santos; Cardoso, Beatriz D.; Souza, Reinaldo Rodrigues de; Moita, Ana S.; Ribeiro, J.E.; Lima, Rui A.Thermal regulation has assumed a central role in space expeditions ever since the inception of Sputnik-1 in 1957. Throughout the years, numerous techniques have been developed to regulate temperatures in spacecraft and space habitats. Initially, passive systems like heat shields and thermal linings were employed, while newer missions embrace active cooling using fluids like ammonia and water. With significant a...
A Review of Methods to Modify the PDMS Surface Wettability and Their Applications
Neves, Lucas Boniatti; Afonso, Inês Santos; Nobrega, Glauco Tapijara Vallicelli; Barbosa, Luiz G.; Lima, Rui A.; Ribeiro, J.E.Polydimethylsiloxane (PDMS) has attracted great attention in various fields due to its excellent properties, but its inherent hydrophobicity presents challenges in many applications that require controlled wettability. The purpose of this review is to provide a comprehensive overview of some key strategies for modifying the wettability of PDMS surfaces by providing the main traditional methods for this modifica...
Experimental evaluation of green nanofluids in heat exchanger made oF PDMS
Nobrega, Glauco Tapijara Vallicelli; Souza, Reinaldo Rodrigues de; Cardoso, Beatriz D.; Afonso, Inês Santos; Pereira, José Eduardo; Cardoso, ElaineConventional methods for synthesizing metallic nanoparticles face challenges such as instability and environmental concerns. Therefore, new, simpler, and more eco-friendly methods are being explored. In this context, the study reports a green synthesis process to produce magnetic iron oxide nanoparticles using an aqueous extract of the alga Chlorella vulgaris. This process leverages natural resources to create ...
Green synthesis of nanoparticles from olive oil waste for environmental and hea...
Afonso, Inês Santos; Cardoso, Beatriz D.; Nobrega, Glauco Tapijara Vallicelli; Minas, Graça; Ribeiro, J.E.; Lima, Rui A.Environmental degradation is a growing concern, driving researchers to explore eco-friendly nanoparticle (NP) synthesis, for diverse applications. Within this context, the employment of olive oil waste (OOW) as a green source for the synthesis of NPs has emerged as a viable alternative to conventional techniques. The olive industry has a significant impact in the Mediterranean region, and alongside it, comes th...
Exploring heat exchange in space: recent advances in two-phase fluid experiment...
Nobrega, Glauco; Afonso, Inês Santos; Cardoso, Beatriz; Souza, Reinaldo Rodrigues de; Moita, Ana; Ribeiro, João EduardoThermal regulation has assumed a central role in space expeditions ever since the inception of Sputnik-1 in 1957. Throughout the years, numerous techniques have been developed to regulate temperatures in spacecraft and space habitats. Initially, passive systems like heat shields and thermal linings were employed, while newer missions embrace active cooling using fluids like ammonia and water. With significant a...
Conventional and recent advances of vegetable oils as metalworking fluids (MWFs...
Afonso, Inês Santos; Nobrega, Glauco Tapijara Vallicelli; Lima, Rui A.; Gomes, José R.; Ribeiro, J.E.Vegetable oils have been used as metalworking fluids (MWFs) for many years, particularly in small-scale metalworking operations and in industries where environmental regulations are strict. Before the development of modern MWFs, vegetable oils were one of the most common lubricants used for metalworking tools. The use of vegetable oils can be traced back to ancient civilizations such as Egypt, Greece, and Rome,...
Didactic analysis of olive mill wastewaters antimicrobial activity
Afonso, Inês Santos; Duarte, Cristina Nogueira; Ribeiro, António E.; Amaral, Joana S.; Ribeiro, J.E.The olive oil production industry is a relevant economic activity in the Mediterranean countries. However, in the extraction process a large amount of a residual effluent called olive mill wastewaters (OMWW) is produced, which represents a large environmental problem. The physicochemical composition of the OMWWis variable but can be characterized by a high organic load, acidic pH, intense oily smell, and a dark...