Publications by authors named "Charitidis C"

The recycling of Carbon Fibre-Reinforced Polymers (CFRPs) is becoming increasingly crucial due to the growing demand for sustainability in high-performance industries such as automotive and aerospace. This study investigates the impact of two chemical recycling techniques, chemically assisted solvolysis and plasma-enhanced solvolysis, on the morphology and properties of carbon fibres (CFs) recovered from end-of-life automotive parts. In addition, the effects of fibre sizing are explored to enhance the performance of the recycled carbon fibres (rCFs).

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In this paper, we explore a straightforward two-step method to produce high-purity, vertically aligned multi-walled carbon nanofibres (MWCNFs) via chemical vapor deposition (CVD). Two distinct solutions are utilized for this CVD method: a catalytic solution consisting of ferrocene and acetonitrile (ACN) and a carbon source solution with camphor and ACN. The vapors of the catalytic solution inserted in the reaction chamber through external boiling result in a floating catalyst CVD approach that produces vertically aligned CNFs in a consistent manner.

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Article Synopsis
  • - The study aimed to assess the mechanical properties of Clear Aligners after they were used in the mouth for various lengths of time (7, 10, and 14 days) and compare them to new, unused aligners.
  • - Researchers analyzed 32 aligners from four patients, conducting tests to measure elastic modulus, ultimate tensile stress (UTS), yield stress, and hardness, resulting in 96 samples and 16 samples of the raw material used for manufacturing.
  • - Findings revealed that the mechanical properties of the processed aligners significantly decreased over time, while the unprocessed material consistently showed superior properties, indicating that the manufacturing and aging processes negatively impact aligner performance.
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In the present study, the feasibility to achieve localized induction heating and debonding of multi-material composite structures is assessed in testing coupons prepared by Automated Fiber Placement (AFP) and extrusion-based additive manufacturing (AM) technologies. Nano-compounds of Polyether-ketone-ketone (PEKK) with iron oxide nanoparticles acting as electromagnetic susceptors have been processed in a parallel co-rotating twin-screw extruder to produce filament feedstock for extrusion-based AM. The integration of nanocomposite interlayers as discrete debonding zones (DZ) by AFP-AM manufacturing has been investigated for two types of sandwich-structured laminate composites, i.

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High electrical conductivity, along with high piezoresistive sensitivity and stretchability, are crucial for designing and developing nanocomposite strain sensors for damage sensing and on-line structural health monitoring of smart carbon fiber-reinforced polymer (CFRP) composites. In this study, the influence of the geometric features and loadings of carbon-based nanomaterials, including reduced graphene oxide (rGO) or carbon nanofibers (CNFs), on the tunable strain-sensing capabilities of epoxy-based nanocomposites was investigated. This work revealed distinct strain-sensing behavior and sensitivities (gauge factor, GF) depending on both factors.

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Infectious diseases are acknowledged as one of the leading causes of death worldwide. Statistics show that the annual death toll caused by bacterial infections has reached 14 million, most of which are caused by drug-resistant strains. Bacterial antibiotic resistance is currently regarded as a compelling problem with dire consequences, which motivates the urgent identification of alternative ways of fighting bacteria.

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This study explores the enhancement of Carbon Fibre Reinforced Polymers (CFRPs) for automotive applications through the integration of modified carbon fibres (CF) and epoxy matrices. The research emphasizes the use of block copolymers (BCPs) and electropolymerisation techniques to improve mechanical properties and interfacial adhesion. Incorporating 2.

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The possibility of directly growing carbon nanofibers (CNFs) and carbon nanotubes (CNTs) on half-Heusler alloys by Chemical Vapour Deposition (CVD) is investigated for the first time, without using additional catalysts, since the half-Heusler alloys per se may function as catalytic substrates, according to the findings of the current study. As a carbon source, acetylene is used in the temperature range of 700-750 °C. The n-type half-Heusler compound Zr0.

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According to the World Health Organization, the proportion of the world's population over 60 years will approximately double by 2050. This progressive increase in the elderly population will lead to a dramatic growth of age-related diseases, resulting in tremendous pressure on the sustainability of healthcare systems globally. In this context, finding more efficient ways to address cancers, a set of diseases whose incidence is correlated with age, is of utmost importance.

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Novel two-layer nanostructured electrodes are successfully prepared for their application in membrane capacitive deionization (MCDI) processes. Nanostructured carbonaceous materials such as graphene oxide (GO) and carbon nanotubes (CNTs), as well as activated carbon (AC) are dispersed in a solution of poly(vinyl alcohol) (PVA), mixed with polyacrylic acid (PAA) or polydimethyldiallylammonium chloride (PDMDAAC), and subsequently cast on the top surface of an AC-based modified graphite electrode to form a thin composite layer that is cross-linked with glutaraldehyde (GA). Cyclic voltammetry (CV) is performed to investigate the electrochemical properties of the composite electrodes and desalination experiments are conducted in batch mode using a MCDI unit cell to investigate the effects of i) the nanostructured carbonaceous material, ii) its concentration in the polymer blend, and iii) the molecular weight of the polymers on the desalination efficiency of the system.

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The development of nanocomposites relies on structure-property relations, which necessitate multiscale modeling approaches. This study presents a modeling framework that exploits mesoscopic models to predict the thermal and mechanical properties of nanocomposites starting from their molecular structure. In detail, mesoscopic models of polypropylene (PP)- and graphene-based nanofillers (graphene (Gr), graphene oxide (GO), and reduced graphene oxide (rGO)) are considered.

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High-density polyethylene polymer (HDPE) and carbon black (CB) were utilized to create HDPE/CB composites with different filler concentrations (0.0, 2.0, 4.

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With an ever-increasing material and design space available for Fused Filament Fabrication (FFF) technology, fabrication of complex three-dimensional structures with functional performance offers unique opportunities for product customization and performance-driven design. However, ensuring the quality and functionality of FFF-printed parts remains a significant challenge, as material-, process-, and system-level factors introduce variability and potentially hinder the translation of bulk material properties in the respective FFF counterparts. To this end, the present study presents a methodological framework for assessing the influence of process parameters on FFF strand stability and functional performance through a systematic analysis of FFF structural elements (1D stacks of FFF strands and 3D blocks), in terms of dimensional deviation from nominal geometry and resistivity, corresponding to the printability and functionality attributes, respectively.

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The generation of 3D structures comprises three interlinked phases: material development, the printing process, and post-printing treatment. Numerous factors control all three phases, making the optimization of the entire process a challenging task. Until now, the state of the art has mainly focused on optimizing material processability and calibration of the printing process.

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The increase of human and environmental exposure to engineered nanomaterials (ENMs) due to the emergence of nanotechnology has raised concerns over their safety. The challenging nature of and toxicity assessment methods for ENMs, has led to emerging techniques for ENM toxicity assessment, such as structure-activity relationship (SAR) models. Although such approaches have been extensively developed for the case of single-component nanomaterials, the case of multicomponent nanomaterials (MCNMs) has not been thoroughly addressed.

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Nanoparticles are being used in novel applications of the thermoplastics industry, including automotive parts, the sports industry and leisure and consumer goods, which can be produced nowadays through additive manufacturing. However, there is limited information on the health and safety aspects during the production of these new materials, mainly from recycled sources. This study covers the exposure assessment to nano- and micro-size particles emitted from the nanocomposites during the production of filaments for 3D printing through a compounding and extrusion pilot line using recycled (post-industrial) thermoplastic polyurethane (TPU) and recycled polyamide 12 (PA12), which have been also upcycled through reinforcement with iron oxide nanoparticles (FeO NPs), introducing matrix healing properties triggered by induction heating.

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The fast and global spread of bacterial resistance to currently available antibiotics results in a great and urgent need for alternative antibacterial agents and therapeutic strategies. Recent studies on the application of nanomaterials as antimicrobial agents have demonstrated their potential for the management of infectious diseases. Among the diverse palette of nanomaterials currently used in biomedical applications, carbon nanotubes (CNTs) have gained massive interest given their many valuable properties, such as high thermal and electrical conductivity, tensile strength, flexibility convenient aspect ratio, and low fabrication costs.

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The surgical treatment for severe deformity correction in patients with Parkinson's disease (PD) is usually challenging, requiring lengthy fusions, and with a high risk of postoperative complications. We present a patient with severe kyphoscoliosis and medical history of PD undergoing minimally invasive surgical deformity correction. A 75-year-old female with a 10-year history of medically controlled PD presented at our hospital's outpatient reporting progressive postural changes during the last two years and a half.

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The identification of health risks arising from occupational exposure to submicron/nanoscale materials is of particular interest and toxicological investigations designed to assess their hazardous properties can provide valuable insights. The core-shell polymers poly (methyl methacrylate)@poly (methacrylic acid-co-ethylene glycol dimethacrylate) [PMMA@P (MAA-co-EGDMA)] and poly (n-butyl methacrylate-co-ethylene glycol dimethacrylate)@poly (methyl methacrylate) [P (nBMA-co-EGDMA)@PMMA] could be utilized for the debonding of coatings and for the encapsulation and targeted delivery of various compounds. The hybrid superabsorbent core-shell polymers poly (methacrylic acid-co-ethylene glycol dimethacrylate)@silicon dioxide [P (MAA-co-EGDMA)@SiO] could be utilized as internal curing agents in cementitious materials.

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Article Synopsis
  • Recent developments in magneto-mechanical therapies show promise in improving or replacing traditional treatment methods, but key areas, like the relationship between magnetic nanocomposite geometry and cell death pathways, remain unclear.
  • This study compares the effects of ZnFeO-PLGA magnetic nanospheres (MNSs) and magnetic nanochains (MNCs) on cell death under low-frequency rotating magnetic fields (RMF), revealing that their distinct shapes lead to different propulsion modes and therapeutic behaviors.
  • Findings indicate that MNSs are more likely to induce apoptosis (programmed cell death), while MNCs are associated with necrosis (uncontrolled cell death), providing insights for enhancing future biomedical applications through tailored nanocomposite designs.
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During Carbon Fibre Reinforced Polymers (CFRPs) manufacturing, large quantities of scrap are being produced and usually disposed to landfill or incinerated, resulting in a high environmental impact. Furthermore, CFRP parts that have been damaged or reached their end-of-life, follow the same disposal route and because of this, not only the environment is affected, but also high added-value materials, such as carbon fibres (CFs) are lost without further valorisation. Several recycling technologies have been suggested, such as pyrolysis, to retrieve the CF reinforcement from the CFRPs.

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Multi-walled carbon nanotubes (MWCNTs) are tubular-shaped carbon allotropes, composed of multiple concentric graphene cylinders. The extended systems of conjugated double bonds, that MWCNTs are constituted by, provide them with high electron affinities, enabling them to act as electron donors or acceptors. Consequently, their potential biomedical applications, as synthetic antioxidant agents, are of particular interest.

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The increasing intentional and non-intentional exposure to nanoparticles (NPs) has raised the interest concerning their fate and biodistribution in the body of animals and humans after inhalation. In this context, Physiologically Based (pharmaco)Kinetic (PBK) modelling has emerged as an in silico approach that simulates the biodistribution kinetics of NPs in the body using mathematical equations. Due to restrictions in data availability, such models are first developed for rats or mice.

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The increasing exposure to gold nanoparticles (AuNPs), due to their wide range of applications, has led to the need for thorough understanding of their biodistribution, following exposure. The objective of this paper is to develop a PBK model in order to study the clearance, retention and translocation of inhaled gold nanoparticles in rats, providing a basis for the understanding of the absorption, distribution, metabolism and elimination (ADME) mechanisms of AuNPs in various organs. A rat PBK computational model was developed, connected to a detailed respiratory model, including the olfactory, tracheobronchial, and alveolar regions.

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