DSpace Collection:https://hdl.handle.net/10216/267682026-07-10T14:36:40Z2026-07-10T14:36:40ZIntegrated Valorization of Food Waste as Catalytic Supports and Feedstocks for Bio-Based Chemicals and Fuelshttps://hdl.handle.net/10216/1745562026-06-23T06:38:56Z2026-01-01T00:00:00ZTitle: Integrated Valorization of Food Waste as Catalytic Supports and Feedstocks for Bio-Based Chemicals and Fuels2026-01-01T00:00:00ZCatalytic Conversion of Biomass-Derived Sugars to Furfuralhttps://hdl.handle.net/10216/1745522026-06-17T06:49:52Z2026-01-01T00:00:00ZTitle: Catalytic Conversion of Biomass-Derived Sugars to Furfural2026-01-01T00:00:00ZHydrodeoxygenation of a furfural-levulinic acid condensation product for the synthesis of aviation fuel precursorshttps://hdl.handle.net/10216/1740312026-05-27T06:48:07Z2026-01-01T00:00:00ZTitle: Hydrodeoxygenation of a furfural-levulinic acid condensation product for the synthesis of aviation fuel precursors2026-01-01T00:00:00ZEncapsulation and Co-encapsulation ff Micronutrients Through Spray Drying For Enhanced Stability and Bioavailabilityhttps://hdl.handle.net/10216/1742892026-05-06T06:40:27Z2025-01-01T00:00:00ZTitle: Encapsulation and Co-encapsulation ff Micronutrients Through Spray Drying For Enhanced Stability and Bioavailability2025-01-01T00:00:00ZElectrohydrodynamic-Based Microencapsulation of Vitamin E: Unlocking New Frontiers in Dermatological and Cosmetic Treatmentshttps://hdl.handle.net/10216/1742842026-05-06T06:22:16Z2025-01-01T00:00:00ZTitle: Electrohydrodynamic-Based Microencapsulation of Vitamin E: Unlocking New Frontiers in Dermatological and Cosmetic Treatments2025-01-01T00:00:00ZDevelopment and Characterization of Alginate Microparticles for Targeted Polyphenol Delivery to Skinhttps://hdl.handle.net/10216/1742642026-05-06T06:37:02Z2025-01-01T00:00:00ZTitle: Development and Characterization of Alginate Microparticles for Targeted Polyphenol Delivery to Skin2025-01-01T00:00:00ZDesign of Polymeric Delivery Systems for Lycium barbarum Phytochemicals: A Spray Drying Approach for Nutraceuticalshttps://hdl.handle.net/10216/1742612026-05-06T06:17:14Z2025-01-01T00:00:00ZTitle: Design of Polymeric Delivery Systems for Lycium barbarum Phytochemicals: A Spray Drying Approach for Nutraceuticals2025-01-01T00:00:00ZEncapsulation of Unstable Vitamins Via Spray Drying and Electrohydrodynamic Techniques for Potential Cosmeceutical Applicationshttps://hdl.handle.net/10216/1742602026-05-06T06:17:13Z2025-01-01T00:00:00ZTitle: Encapsulation of Unstable Vitamins Via Spray Drying and Electrohydrodynamic Techniques for Potential Cosmeceutical Applications2025-01-01T00:00:00ZCutting-edge natural-based solutions to reduce Campylobacter contamination in poultry meat industryhttps://hdl.handle.net/10216/1694032026-04-25T06:09:42Z2025-05-07T00:00:00ZTitle: Cutting-edge natural-based solutions to reduce Campylobacter contamination in poultry meat industry2025-05-07T00:00:00ZEvaluating the impact of Cooperative Adaptive Cruise Control in ramp metering systemshttps://hdl.handle.net/10216/1734392026-03-20T07:45:53Z2026-02-13T00:00:00ZTitle: Evaluating the impact of Cooperative Adaptive Cruise Control in ramp metering systems2026-02-13T00:00:00ZHarmine-antiseptic dual combination photodynamic therapy for targeting methicillin-resistant Staphylococcus aureushttps://hdl.handle.net/10216/1695022025-10-03T06:19:17Z2025-06-30T00:00:00ZTitle: Harmine-antiseptic dual combination photodynamic therapy for targeting methicillin-resistant Staphylococcus aureus2025-06-30T00:00:00ZSelected monoterpenes as potential biofilm control agents and antibiotic resistance modifiershttps://hdl.handle.net/10216/1694902025-10-03T06:18:35Z2025-06-30T00:00:00ZTitle: Selected monoterpenes as potential biofilm control agents and antibiotic resistance modifiers2025-06-30T00:00:00ZOptimization of an in vitro method for testing novel formulations for poultry meat sanitizinghttps://hdl.handle.net/10216/1694122025-09-25T06:17:37Z2025-05-07T00:00:00ZTitle: Optimization of an in vitro method for testing novel formulations for poultry meat sanitizing2025-05-07T00:00:00ZValorisation of Purple Onion Peel as a Sustainable Biodye for Cotton and Woolhttps://hdl.handle.net/10216/1693402025-09-19T06:16:32Z2025-06-01T00:00:00ZTitle: Valorisation of Purple Onion Peel as a Sustainable Biodye for Cotton and Wool
Abstract: The textile industry is a major contributor to environmental pollution, largely due to high
water consumption and the use of non-biodegradable synthetic dyes, which contaminate
ecosystems and pose risks to human health [1]. Among its processes, dyeing stands out for
high environmental impact. In response, more sustainable alternatives have been explored,
including natural-origin dyes. However, natural dyes still face key limitations, particularly low
colour fastness, as they tend to fade after washing or prolonged exposure to sunlight [2]. This
study investigates the potential of purple onion peel (Allium cepa L.), a by-product of the food
industry, as a sustainable biodye for cotton and wool fabrics. The aim is to evaluate the
effectiveness of this bio-dye as an eco-friendly alternative to synthetic dyes [3]. To evaluate
dye fixation improvement, samples dyed without and with the mordant carbonyldiimidazole
(CDI) used directly in the dyeing solution were compared, testing different concentrations.
The dye was extracted using a simple solid-liquid process with water, and dyeing was
performed under controlled conditions (50 °C, 320 rpm, 100 min). Subsequently, fastness tests
to washing (cold and hot water) and natural light exposition were conducted, with the colour
change evaluated using the CIELAB colour space. Results show that CDI improved dye fixation,
especially in wool, where minimal colour difference was observed between exposed and
protected areas from light. In cotton, colour fastness improved but remained unsatisfactory.
These findings show the potential of using agricultural waste in the textile industry for
sustainable practices within the circular economy. However, the lightfastness limitation
underscores the need for further research on eco-friendly solutions to improve colour
durability.2025-06-01T00:00:00ZHeat and Mass Transfer Through a Firefighter Protective Vest - Numerical Analysis of Materials with Heterogeneous Permeabilityhttps://hdl.handle.net/10216/1693362025-09-19T06:16:26Z2025-06-01T00:00:00ZTitle: Heat and Mass Transfer Through a Firefighter Protective Vest - Numerical Analysis of Materials with Heterogeneous Permeability
Abstract: Developing more efficient firefighter protective clothing is a crucial step towards advancing safety equipment, ensuring better protection against the rising risks of burn injuries and enhancing overall performance in increasingly hazardous fire environments. A recent innovation in firefighter safety is a vest designed to be worn over standard thermal protective clothing, aiming to improve both thermal comfort and safety [1]. While this vest has shown promising performance, its non-uniform material properties [2] can lead to localized zones of water vapor saturation, potentially compromising thermal efficiency.
This study presents a numerical analysis of heat and moisture transport through the vest system, which consists of phase change material (PCM)-filled pouches embedded between textile layers and a perforated cork layer.
The analysis evaluates the impact of PCM layer permeability, as well as the number, diameter, and spatial distribution of perforations, on both thermal and evaporative resistances. Two modeling approaches were adopted: a two-dimensional model assessing both impermeable and permeable pouches, and a three-dimensional model incorporating a permeable PCM configuration.
Results indicate that thermal resistance increases with larger perforation diameters and reduced perforation density, while evaporative resistance is maximized with smaller, fewer perforations. Although both two- and three-dimensional simulations reveal consistent trends, discrepancies in absolute values underscore the limitations of the two-dimensional approximation. As expected, the increase of the permeability of the PCM layer significantly enhances the evaporative performance of the multilayer system. This study highlights the critical role of material and structural design in optimizing the thermal and evaporative performance of firefighter protective gear.2025-06-01T00:00:00ZTextile Dyeing with Natural Dyes: Review and Insights from a Novel Mathematical Modelhttps://hdl.handle.net/10216/1693352025-09-19T06:16:26Z2025-06-01T00:00:00ZTitle: Textile Dyeing with Natural Dyes: Review and Insights from a Novel Mathematical Model
Abstract: The growing environmental concerns surrounding synthetic dyes have intensified the search
for sustainable alternatives in the textile industry [1]. Conventional dyeing processes consume
excessive water and release toxic, non-biodegradable compounds into ecosystems. In this
context, natural dyes-derived from renewable sources such as plants-offer a promising,
eco-friendly solution. This work presents a concise review of the state-of-the-art in textile
dyeing with natural dyes, highlighting current challenges and advancements. Few
mathematicalmodels of textile dyeing process have been reported focusing mainly on the use
of chemical dyes [2] or the treatment of textile dye effluents [3]. Concerning mass transfer
phenomena, the dyeing process is modelled considering the dye molecules diffusion through
the textile porous and their sorption/desorption dynamics with the fibers. In this study, we
present insights from a novel mathematical model developed to simulate the dyeing process
with natural colorants. As a case study, cotton and wool samples were dyed with pigments
extracted from purple onion peel. A one-dimensional numerical approach, combined with
volume-averaging techniques, was employed to study mass transfer across the sample
thickness and predict dye concentration distribution over time. As an advantage, this type of
models enables the prediction and optimization of dye-fiber interactions under various
conditions, providing guidance for developing efficient, environmentally responsible dyeing
workflows.2025-06-01T00:00:00ZPhotocatalytic reforming of biomass for sustainable hydrogen productionhttps://hdl.handle.net/10216/1681132025-07-27T06:22:12Z2025-01-01T00:00:00ZTitle: Photocatalytic reforming of biomass for sustainable hydrogen production2025-01-01T00:00:00ZFísica fora da sala de aula com smartphonehttps://hdl.handle.net/10216/1615262025-05-10T06:21:52Z2024-09-11T00:00:00ZTitle: Física fora da sala de aula com smartphone
Description: O smartphone é o acessório ubíquo dos estudantes. Usado maioritariamente para entretenimento, várias das suas capacidades são desconhecidas, sendo comum encontrar na sala de aula estudantes com smartphone e calculadora gráfica, porque desconhecem a existência de aplicações que são calculadoras gráficas. Outro exemplo é o desconhecimento que o smartphone contém sensores como por exemplo, acelerómetro ou magnetómetro, dois dos mais comuns. Também desconhecem igualmente aplicações, gratuitas, seguras e de código aberto, que permitem aceder aos valores em bruto destes sensores, e até exportá-los para um computador pessoal, transformando os smartphones em instrumentos de medida e aquisição de dados.
Ajudar o estudante a explorar estas potencialidades do smartphone é importante. Permite levar a física para fora dos manuais, oferecendo a oportunidade de olhar para o smartphone como um minilaboratório que está sempre no seu bolso e pode ser usado fora da sala de aula, quando for oportuno.
Neste trabalho serão apresentadas propostas para alguns trabalhos de casa a atribuir aos estudantes. Será descrito como se pode medir, a orientação das linhas do campo geomagnético local, os campos magnéticos criados pelas linhas elétricas do metro do Porto, usando o magnetómetro do smartphone, e estudar as propriedades dum oscilador harmónico simples ou amortecido usando o acelerómetro.2024-09-11T00:00:00ZDevelopment of a nanoformulation containing drugs with osseointegration and antimicrobial properties to improve the success of dental implantationhttps://hdl.handle.net/10216/1666482025-05-10T06:21:50Z2025-05-07T00:00:00ZTitle: Development of a nanoformulation containing drugs with osseointegration and antimicrobial properties to improve the success of dental implantation2025-05-07T00:00:00ZOS PARABENOS AFETAM A VIRULÊNCIA DE BACTÉRIAS DE ÁGUA POTÁVEL COM POTENCIAIS RISCOS PARA A SAÚDE PÚBLICAhttps://hdl.handle.net/10216/1665602025-05-04T06:21:49Z2024-01-01T00:00:00ZTitle: OS PARABENOS AFETAM A VIRULÊNCIA DE BACTÉRIAS DE ÁGUA POTÁVEL COM POTENCIAIS RISCOS PARA A SAÚDE PÚBLICA2024-01-01T00:00:00Z