RESUMEN
The sensitivity of zinc (Zn(II)) detection using fast-scan cyclic voltammetry (FSCV) with carbon fiber microelectrodes (CFMEs) is low compared to other neurochemicals. We have shown previously that Zn(II) plates to the surface of CFME's and we speculate that it is because of the abundance of oxide functionality on the surface. Plating reduces sensitivity over time and causes significant disruption to detection stability. This limited sensitivity and stability hinders Zn(II) detection, especially in complex matrices like the brain. To address this, we developed plasma-treated gold fiber microelectrodes (AuMEs) which enable sensitive and stable Zn(II) detection with FSCV. Typically, gold fibers are treated using corrosive acids to clean the surface and this step is important for preparing the surface for electrochemistry. Likewise, because FSCV is an adsorption-based technique, it is also important for Zn(II) to adsorb and desorb to prevent irreversible plating. Because of these requirements, careful optimization of the electrode surface was necessary to render the surface for Zn(II) adsorption yet strike a balance between attraction to the surface vs. irreversible interactions. In this study, we employed oxygen plasma treatment to activate the gold fiber surface without inducing significant morphological changes. This treatment effectively removes the organic layer while functionalizing the surface with oxygen, enabling Zn(II) detection that is not possible on untreated gold surfaces. Our results demonstrate significantly improved Zn(II) detection sensitivity and stability on AuME compared to CFME's. Overall, this work provides an advance in our understanding of Zn(II) electrochemistry and a new tool for improved metallotransmitter detection in the brain.
Asunto(s)
Técnicas Electroquímicas , Oro , Microelectrodos , Zinc , Zinc/química , Oro/química , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Fibra de Carbono/química , Gases em Plasma/química , Carbono/química , Adsorción , Oxígeno/químicaRESUMEN
Nowadays, owing to the new technological and industrial requirements for equipment, such as flexibility or multifunctionally, the development of all-solid-state supercapacitors and Li-ion batteries has become a goal for researchers. For these purposes, the composite material approach has been widely proposed due to the promising features of woven carbon fiber as a substrate material for this type of material. Carbon fiber displays excellent mechanical properties, flexibility, and high electrical conductivity, allowing it to act as a substrate and a collector at the same time. However, carbon fiber's energy-storage capability is limited. Several coatings have been proposed for this, with nanostructured transition metal oxides being one of the most popular due to their high theoretical capacity and surface area. In this overview, the main techniques used to achieve these coatings-such as solvothermal synthesis, MOF-derived obtention, and electrochemical deposition-are summarized, as well as the main strategies for alleviating the low electrical conductivity of transition metal oxides, which is the main drawback of these materials.
Asunto(s)
Fibra de Carbono , Capacidad Eléctrica , Suministros de Energía Eléctrica , Electrodos , Litio , Nanoestructuras , Óxidos , Litio/química , Fibra de Carbono/química , Óxidos/química , Nanoestructuras/química , Elementos de Transición/química , Conductividad Eléctrica , Metales/químicaRESUMEN
Secondary healing of fractured bones requires an application of an appropriate fixator. In general, steel or titanium devices are used mostly. However, in recent years, composite structures arise as an attractive alternative due to high strength to weight ratio and other advantages like, for example, radiolucency. According to Food and Drug Administration (FDA), the only unidirectionally reinforced composite allowed to be implanted in human bodies is carbon fiber (CF)-reinforced poly-ether-ether-ketone (PEEK). In this work, the healing process of long bone assembled with CF/PEEK plates with cross- and angle-ply lay-up configurations is studied in the framework of finite element method. The healing is simulated by making use of the mechanoregulation model basing on the Prendergast theory. Cells transformation is determined by the octahedral shear strain and interstitial fluid velocity. The process runs iteratively assuming single load cycle each day. The fracture is subjected to axial and transverse forces. In the computations, the Abaqus program is used. It is shown that the angle-ply lamination scheme of CF/PEEK composite seems to provide better conditions for the transformation of the soft callus into the bone tissue.
Asunto(s)
Benzofenonas , Placas Óseas , Fibra de Carbono , Curación de Fractura , Cetonas , Polietilenglicoles , Polímeros , Cetonas/química , Fibra de Carbono/química , Polietilenglicoles/química , Polímeros/química , Humanos , Carbono/química , Fracturas Óseas , Análisis de Elementos FinitosRESUMEN
Living organisms have developed a miraculous biomineralization strategy to form multistage organic-inorganic composites through the orderly assembly of hard/soft substances, achieving mechanical enhancement of materials from the nanoscale to the macroscale. Inspired by biominerals, this study used polydopamine (PDA) coating as a template to induce the growth of hydroxyapatite (HAP) on the surface of carbon fibers (CFs) for enhancing the interfacial properties of the CF/epoxy resin composites. This polydopamine-assisted hydroxyapatite formation (pHAF) biomimetic mineralization strategy constructs soft/hard ordered structure on the CF surface, which not only improves the chemical reaction activity of the CFs but also increases the fiber surface roughness. This, in turn, enhances the interaction and loading delivery among the fibers and the matrix. Compared to the untreated carbon fiber/epoxy resin (CF/EP) composites, the prepared composites showed a substantial enhancement in interlaminar shear strength (ILSS), flexural strength, and interfacial shear strength (IFSS), with improvements of 45.2 %, 46.9 %, and 60.5 %, respectively. This can be attributed to the HAP nanolayers increasing the adhesion and mechanical interlocking with the CFs to the matrix. This study provides an interface modification method of biomimetic mineralization for the preparation of high strength CF composites.
Asunto(s)
Fibra de Carbono , Durapatita , Indoles , Polímeros , Indoles/química , Durapatita/química , Polímeros/química , Fibra de Carbono/química , Materiales Biomiméticos/química , Biomimética/métodos , Fenómenos Mecánicos , Resistencia al Corte , Propiedades de Superficie , Resinas Epoxi/químicaRESUMEN
The development of integrated analytical devices is crucial for advancing next-generation point-of-care platforms. Herein, we describe a facile synthesis of a strongly catalytic and durable Nitrogen-doped graphene oxide decorated platinum cobalt (NGO-PtCo) nanocomposite that is conjugated with target-specific DNA aptamer (i-e. MUC1) and grown on carbon fiber. Benefitting from the combined features of the high electrochemical surface area of N-doped GO, high capacitance and stabilization by Co, and high kinetic performance by Pt, a robust, multifunctional, and flexible nanotransducer surface was created. The designed platform was applied for the specific detection of a blood-based oncomarker, CA15-3. The electrochemical characterization proved that nanosurface provides a highly conductive and proficient immobilization support with a strong bio-affinity towards MUC1 aptamer. The specific interaction between CA15-3 and the aptamer alters the surface properties of the aptasensor and the electroactive signal probe generated a remarkable increase in signal intensity. The sensor exhibited a wide dynamic range of 5.0 × 10-2 -200 U mL-1, a low limit of detection (LOD) of 4.1 × 10-2 U mL-1, and good reproducibility. The analysis of spiked serum samples revealed outstanding recoveries of up to 100.03 %, by the proposed aptasensor. The aptasensor design opens new revelations in the reliable detection of tumor biomarkers for timely cancer diagnosis.
Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Fibra de Carbono , Cobalto , Técnicas Electroquímicas , Grafito , Mucina-1 , Nanocompuestos , Platino (Metal) , Aptámeros de Nucleótidos/química , Técnicas Electroquímicas/métodos , Grafito/química , Humanos , Mucina-1/sangre , Mucina-1/análisis , Cobalto/química , Nanocompuestos/química , Platino (Metal)/química , Técnicas Biosensibles/métodos , Fibra de Carbono/química , Límite de DetecciónRESUMEN
The objective of the present study was to evaluate the carbon fiber obtained from textile PAN fiber, in its different forms, as a potential scaffolds synthetic bone. Thirty-four adult rats were used (Rattus norvegicus, albinus variation), two critical sized bone defects were made that were 5 mm in diameter. Twenty-four animals were randomly divided into four groups: control (C)-bone defect + blood clot, non-activated carbon fiber felt (NACFF)-bone defect + NACFF, activated carbon fiber felt (ACFF)-bone defect + ACFF, and silver activated carbon fiber felt (Ag-ACFF)-bone defect + Ag-ACFF, and was observed by 15 and 60 days for histomorphometric, three-dimensional computerized microtomography (microCT) and mineral apposition analysis. On histomorphometric and microCT analyses, NACFF were associated with higher proportion of neoformed bone and maintenance of bone structure. On fluorochrome bone label, there was no differences between the groups. NACFF has shown to be a promising synthetic material as a scaffold for bone regeneration.
Asunto(s)
Regeneración Ósea , Fibra de Carbono , Carbono , Andamios del Tejido , Microtomografía por Rayos X , Animales , Ratas , Regeneración Ósea/efectos de los fármacos , Andamios del Tejido/química , Carbono/química , Fibra de Carbono/química , Masculino , Textiles , Brasil , Ensayo de Materiales , Ratas WistarRESUMEN
Cell therapy and engineered tissue creation based on the use of human stem cells involves cell isolation, expansion, and cell growth and differentiation on the scaffolds. Microbial infections dramatically can affect stem cell survival and increase the risk of implant failure. To prevent these events, it is necessary to develop new materials with antibacterial properties for coating scaffold surfaces as well as medical devices, and all other surfaces at high risk of contamination. This chapter describes strategies for obtaining antibacterial blends for coating inert surfaces (polymethylmethacrylate, polycarbonate, Carbon Fiber Reinforced Polymer (CFRP)). In particular, the procedures for preparing antibacterial blends by mixing polymer resins with two types of antibacterial additives and depositing these blends on inert surfaces are described.
Asunto(s)
Células Madre , Ingeniería de Tejidos , Humanos , Ingeniería de Tejidos/métodos , Células Madre/citología , Propiedades de Superficie , Andamios del Tejido/química , Antibacterianos/farmacología , Cemento de Policarboxilato/química , Técnicas de Cultivo de Célula/métodos , Polimetil Metacrilato/química , Fibra de Carbono/química , Carbono/química , Antiinfecciosos/farmacologíaRESUMEN
Here we report a novel chemical recycling of carbon fiber-reinforced plastic (CFRP) using meta-chloroperoxybenzoic acid (mCPBA) as the representative oxidizing agent. The optimal decomposition conditions for the epoxy (EP) resin in CFRP were investigated by varying mCPBA concentration and reaction time. The CFRP decomposed completely within 6 h using a 1.5 M mCPBA solution at 40 °C. Tensile strength of recovered CF (r-CF) measured 4.4 GPa, 93.6% of virgin CF (v-CF), and electrical conductivity reached 590 S/cm, 95% of v-CF. Furthermore, the interfacial shear strength (IFSS) of the recovered carbon fibers (r-CF) using EP resin and polyamide 6 (PA6) was analyzed. For EP resin, the IFSS of r-CF was 88 MPa, a 26 % increase compared to v-CF. In the case of PA6 resin, IFSS values were 80 MPa for r-CF, a 17% improvement over v-CF. The study highlights superior mechanical properties and favorable IFSS of r-CF, positioning them as promising for composite regeneration. Remarkably, this method operated at relatively low temperatures compared to existing technologies, with energy consumption recorded at 35 MJ/kg, establishing it as the most energy-efficient recycling method available.
Asunto(s)
Fibra de Carbono , Reciclaje , Resistencia al Corte , Fibra de Carbono/química , Reciclaje/métodos , Plásticos/química , Resinas Epoxi/química , Resistencia a la Tracción , Carbono/química , Caprolactama/análogos & derivados , PolímerosRESUMEN
Photocatalytic antimicrobials, as emerging advanced oxidative antimicrobial materials, have the advantages of low price and long-lasting antimicrobial properties. Nevertheless, with catalysts increasingly trending toward nanoscale dimensions, the environmental challenge of catalyst recycling becomes more pronounced. In this paper, we propose utilizing one-dimensional carbon fiber as a substrate, employing the nucleating agent method to induce Titanium dioxide (TiO2) growth on the fiber surface. Furthermore, the material's band gap underwent modification through hydrogen calcination, thus resulting in the attainment of hierarchical black TiO2/carbon fiber composites with visible light-driven capabilities. The characterization of the materials was conducted via scanning electron microscope (SEM), X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). The results revealed that when the black hydrogenated TiO2 was composited with carbon fiber, the Schottky heterojunction was formed, and thus effectively improved the photocatalytic effect of the composites. Notably, the degradation rate of methylene blue achieved 96.25% within 150 min when utilizing black TiO2/carbon fiber composites, while the inactivation rate of Escherichia coli (E. coli) reached 97.58% within 0.5 h and attained complete inactivation within 60 min.
Asunto(s)
Fibra de Carbono , Escherichia coli , Ensayo de Materiales , Tamaño de la Partícula , Titanio , Titanio/química , Escherichia coli/efectos de los fármacos , Catálisis , Fibra de Carbono/química , Procesos Fotoquímicos , Luz , Propiedades de Superficie , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Materiales Biocompatibles/síntesis química , Antibacterianos/química , Antibacterianos/farmacología , Antibacterianos/síntesis química , Carbono/química , Azul de Metileno/químicaRESUMEN
In this study, a hydrothermal process was utilized to grow mixed-valence CuFe2O4/Cu0 nanosheets on carbon fiber paper, forming a three-dimensional hierarchical electrode (CuFe2O4/Cu0@CFP). The ordered array structure, coupled with the porous bowl-like structure, enhances the exposure of more electrode active sites and facilitates analyte penetration, thus enhancing the electrode sensing performance. As a binder-free sensor, the CuFe2O4/Cu0@CFP sensor exhibited remarkable sensitivity in detecting Malachite Green (MG), Sunset Yellow (SY) and Tartrazine (TA) over wide concentration ranges: 0.1-300 µM for MG (R2 = 0.994), 0.005-200 µM for SY (R2 = 0.996), and 0.005-300 µM for TA (R2 = 0.995) with low detection limits of 0.033 µM for MG, 0.0016 µM for SY, and 0.0016 µM for TA (S/N = 3), respectively. Additionally, the 3D CuFe2O4/Cu0@CFP sensor detected MG, SY, and TA in a mixed solution with satisfactory results. It also performs well in beverage, fruit juice powder, and jelly samples, with results matching those from HPLC.
Asunto(s)
Compuestos Azo , Cobre , Nanoestructuras , Colorantes de Rosanilina , Tartrazina , Cobre/química , Cobre/análisis , Tartrazina/análisis , Tartrazina/química , Nanoestructuras/química , Colorantes de Rosanilina/química , Colorantes de Rosanilina/análisis , Compuestos Azo/química , Compuestos Azo/análisis , Fibra de Carbono/química , Contaminación de Alimentos/análisis , Técnicas Electroquímicas/instrumentación , Límite de Detección , Colorantes de Alimentos/análisis , Colorantes de Alimentos/química , PapelRESUMEN
The adhesive strength between the sizing agent and carbon fiber (CF) plays a crucial role in improving the interfacial properties of composites, while such a vital aspect has been consistently disregarded. In this study, a hyperbranched waterborne polyurethane (HWPU) sizing agent was synthesized from biogenetically raw materials including gallic acid, l-Lysine diisocyanate and amylopectin. Concurrently, hydrogen-bonded cross-linked network structures were established utilizing a botanical polyphenol tannin as coupling agent to effectively connect CF with HWPU. This meticulous process yielded CF/nylon 6 composites with improved properties and their mechanical characteristics were systematically investigated. The findings showcased a noteworthy boost in flexural strength and interlaminar shear strength (ILSS), showing enhancements of 54.6 % and 61.4 %, respectively, surpassing those of untreated CF. Furthermore, the interfacial shear strength (IFSS) test indicated a remarkable 70.3 % improvement. This approach presents a highly promising concept aimed at developing sustainable green waterborne polyurethane sizing agent and improving the interfacial performance of CF composite materials.
Asunto(s)
Amilopectina , Fibra de Carbono , Enlace de Hidrógeno , Polifenoles , Poliuretanos , Poliuretanos/química , Polifenoles/química , Fibra de Carbono/química , Amilopectina/química , Agua/química , Resistencia al CorteRESUMEN
This paper initially examines the feasibility and effectiveness on interfacial adhesion of composites when grafting nanoparticle-structured polydopamine (PDA) and chitosan around carbon fiber periphery. The resulting interfacial shear strength was maximized as 92.3 MPa, delivering 50.1 % and 15.7-16.2 % gains over those of control fiber and only polydopamine nanospheres (PDANPs) or only chitosan modified fiber composites. Measuring surface morphology and thermal stability of fibers found that abundant PDANPs well adhered with the help of chitosan, highlighting nanoscale size effects and intrinsic adhesiveness of PDA. Under good wettability, rich and dense interfacial interactions (covalent and hydrogen bond, electrostatic interaction, and π conjugation) caused by PDANPs/chitosan coating provides impetus for effective stress transfer. Additionally, the stable "soft-rigid" combination of chitosan and PDANPs adds the efficiency of crack passivation. As such, it is hoped that this work could fully explore the possibility of PDA geometry in interphase engineering of fiber composites.
Asunto(s)
Fibra de Carbono , Quitosano , Indoles , Nanosferas , Polímeros , Quitosano/química , Indoles/química , Nanosferas/química , Polímeros/química , Fibra de Carbono/química , HumectabilidadRESUMEN
BACKGROUND: The prosthetic foot is an essential component of the prosthetic limb used by people who suffer from amputation. The prosthetic foot or limb is expensive in developing countries and cannot be used by most people with special needs. OBJECTIVE: In this study, an uncomplicated prosthetic foot is designed that can be manufactured at low costs using 3D printer technology and can be provided to a wide range of amputees. The foot was designed using CAD software and analyzed using ANSES. METHODS: Carbon fiber material was chosen to be suitable for the manufacturing process using 3D printer technology. The selected material was tested in tensile and fatigue tests to determine its mechanical properties. The numerical analysis was carried out assuming the use of an artificial foot by a patient weighing 85 kg. RESULTS: The results showed that the material proposed for manufacturing has good mechanical properties for this application. The results of the engineering analysis also showed that the model has successfully passed the design process and is reliable for use by amputees. CONCLUSION: The success model designed in this study in the numerical analysis process gives reliability to the use of this design to manufacture the prosthetic foot.
Asunto(s)
Miembros Artificiales , Simulación por Computador , Pie , Impresión Tridimensional , Diseño de Prótesis , Humanos , Resistencia a la Tracción , Diseño Asistido por Computadora , Amputados/rehabilitación , Fibra de Carbono/química , Ensayo de Materiales , Análisis de Elementos Finitos , Estrés MecánicoRESUMEN
The hormone Neuropeptide Y (NPY) plays critical roles in feeding, satiety, obesity, and weight control. However, its complex peptide structure has hindered the development of fast and biocompatible detection methods. Previous studies utilizing electrochemical techniques with carbon fiber microelectrodes (CFMEs) have targeted the oxidation of amino acid residues like tyrosine to measure peptides. Here, we employ the modified sawhorse waveform (MSW) to enable voltammetric identification of NPY through tyrosine oxidation. Use of MSW improves NPY detection sensitivity and selectivity by reducing interference from catecholamines like dopamine, serotonin, and others compared to the traditional triangle waveform. The technique utilizes a holding potential of -0.2 V and a switching potential of 1.2 V that effectively etches and renews the CFME surface to simultaneously detect NPY and other monoamines with a sensitivity of 5.8 ± 0.94 nA/µM (n = 5). Furthermore, we observed adsorption-controlled, subsecond NPY measurements with CFMEs and MSW. The effective identification of exogenously applied NPY in biological fluids demonstrates the feasibility of this methodology for in vivo and ex vivo studies. These results highlight the potential of MSW voltammetry to enable fast, biocompatible NPY quantification to further elucidate its physiological roles.
Asunto(s)
Técnicas Electroquímicas , Neuropéptido Y , Neuropéptido Y/análisis , Técnicas Electroquímicas/métodos , Técnicas Electroquímicas/instrumentación , Microelectrodos , Humanos , Oxidación-Reducción , Fibra de Carbono/química , Tirosina/análisis , Tirosina/química , AnimalesRESUMEN
Developing real-time, dynamic, and in situ analytical methods with high spatial and temporal resolutions is crucial for exploring biochemical processes in the brain. Although in vivo electrochemical methods based on carbon fiber (CF) microelectrodes are effective in monitoring neurochemical dynamics during physiological and pathological processes, complex post modification hinders large-scale productions and widespread neuroscience applications. Herein, we develop a general strategy for the in situ engineering of carbon-based materials to mass-produce functional CFs by introducing polydopamine to anchor zeolitic imidazolate frameworks as precursors, followed by one-step pyrolysis. This strategy demonstrates exceptional universality and design flexibility, overcoming complex post-modification procedures and avoiding the delamination of the modification layer. This simplifies the fabrication and integration of functional CF-based microelectrodes. Moreover, we design highly stable and selective H+, O2, and ascorbate microsensors and monitor the influence of CO2 exposure on the O2 content of the cerebral tissue during physiological and ischemia-reperfusion pathological processes.
Asunto(s)
Fibra de Carbono , Carbono , Fibra de Carbono/química , Carbono/química , Técnicas Electroquímicas/métodos , Polímeros/química , Animales , Indoles/química , Microelectrodos , Ácido Ascórbico/química , Oxígeno/química , Oxígeno/metabolismo , Zeolitas/química , Imidazoles/química , Dióxido de Carbono/químicaRESUMEN
Silica aerogels or xerogels are renowned dried gels with low density, high surface area, higher porosity, and better thermal stability which makes it suitable for aerospace, light weight structures, thermal insulation, and hydrophobic coatings. But brittle behaviour, low mechanical strength, and high manufacturing cost restrict its usage. Recently, the addition of various fibres like glass or carbon fiber is one of the best reinforcement methods to minimize the brittle behaviour. Supercritical drying technique usually used to develop aerogel that is expensive and difficult to produce in bulk quantities. Higher cost obstacle can be tackled by applying ambient pressure drying technique to develop xerogel. But researcher observed cracks in samples prepared through the ambient pressure drying technique is still a major shortcoming. The aim of this study is to systematically analyze the influence of silica gel fiber reinforcement on silica xerogels, encompassing morphology, mechanics, thermal behaviour, compression test, and thermogravimetric characteristics. The research used a low-cost precursor named Tetraethyl orthosilicate to synthesize low-cost composite Silica xerogel and glass and carbon fiber added to provide strength and flexibility to the overall composite. Silica gel works as binder in strengthening the xerogel network. The investigation employs scanning electron microscopy (SEM) to examine the morphology of the composites, Fourier Transform Infrared (FTIR) analysis to affirm hydrophobic characteristics, compression tests to assess mechanical strength, and thermogravimetric tests to study weight loss under different conditions. SEM results reveals that glass fibers exhibit lower adhesion to the xerogel network compared to carbon fibers. FTIR analysis confirms the hydrophobicity of the composite silica xerogel. Compression tests showed that, under a 48% strain rate, the carbon fiber composite demonstrates superior compressive stress endurance. Thermogravimetric tests revealed a 1% lower weight loss for the carbon fiber composite compared to the glass fiber composite. This work concludes that glass and carbon fiber together with silica gel particles successfully facilitated in developing flexible, less costly, hydrophobic, and crack-free silica xerogel composites by APD. These advancements have the potential to drive innovations in material science and technology across diverse industries.
Asunto(s)
Dióxido de Silicio , Dióxido de Silicio/química , Termogravimetría , Geles/química , Gel de Sílice/química , Vidrio/química , Temperatura , Fibra de Carbono/química , Microscopía Electrónica de Rastreo , Porosidad , Ensayo de Materiales , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
In order to investigate the effect of boron element on liquefied wood carbon fibers and their composites, boric acid and boron carbide were utilized to modify liquefied wood resin through copolymerization and blending methods respectively. Then boric acid-modified liquefied wood carbon fiber (BA-WCF) and boron carbide-modified liquefied wood carbon fiber (BC-WCF) were produced via melt spinning, curing, and carbonization treatments. As expected, this modification approach effectively prevents the formation of skin-core structures and accelerates the evolution of a graphite microcrystalline structure, thereby enhancing the mechanical properties of the carbon fibers. Particularly, the tensile strength and elongation at break of BA-WCF increased to 331.57 MPa and 7.57 % respectively, representing increments of 117 % and 86 % compared to the conventional fibers. Furthermore, the as-fabricated carbon fiber/resin composites (CFPRs), composing of BA-WCF or BC-WCF as fillers and liquefied wood resin as matrix, exhibited excellent interlaminar shear strength, outstanding abrasion resistance, and well thermal conductivity, as well as electrical performance, significantly outperforming the conventional carbon fiber/phenolic resin composites. The friction rate of BC-WP/BA-WCF/CF was 2.37 %, while its thermal conductivity could reach 1.927 W/(m·K). These promising attributes lay the groundwork for the development of high-performance carbon fiber-based materials, fostering their widespread utilization across various industries.
Asunto(s)
Fibra de Carbono , Conductividad Térmica , Madera , Fibra de Carbono/química , Madera/química , Catálisis , Resistencia a la Tracción , Compuestos de Boro/química , Ácidos BóricosRESUMEN
BACKGROUND: Efficient monitoring of glucose concentration in the human body necessitates the utilization of electrochemically active sensing materials in nonenzymatic glucose sensors. However, prevailing limitations such as intricate fabrication processes, lower sensitivity, and instability impede their practical application. Herein, ternary Cu-Co-Ni-S sulfides nanoporous network structure was synthesized on carbon fiber paper (CP) by an ultrafast, facile, and controllable technique through on-step cyclic voltammetry, serving as a superior self-supporting catalytic electrode for the high-performance glucose sensor. RESULTS: The direct growth of free-standing Cu-Co-Ni-S on the interconnected three-dimensional (3D) network of CP boosted the active site of the composites, improved ion diffusion kinetics, and significantly promoted the electron transfer rate. The multiple oxidation states and synergistic effects among Co, Ni, Cu, and S further promoted glucose electrooxidation. The well-architected Cu-Co-Ni-S/CP presented exceptional electrocatalytic properties for glucose with satisfied linearity of a broad range from 0.3 to 16,000 µM and high sensitivity of 6829 µA mM- 1 cm- 2. Furthermore, the novel sensor demonstrated excellent selectivity and storage stability, which could successfully evaluate the glucose levels in human serum. Notably, the novel Cu-Co-Ni-S/CP showed favorable biocompatibility, proving its potential for in vivo glucose monitoring. CONCLUSION: The proposed 3D hierarchical morphology self-supported electrode sensor, which demonstrates appealing analysis behavior for glucose electrooxidation, holds great promise for the next generation of high-performance glucose sensors.
Asunto(s)
Técnicas Biosensibles , Fibra de Carbono , Cobalto , Cobre , Técnicas Electroquímicas , Electrodos , Níquel , Sulfuros , Cobre/química , Níquel/química , Catálisis , Humanos , Cobalto/química , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos , Sulfuros/química , Fibra de Carbono/química , Glucosa/análisis , Glucosa/química , Nanoporos , Oxidación-Reducción , Glucemia/análisisRESUMEN
Using a curved carbon-fiber plate (CFP) in running shoes may offer notable performance benefit over flat plates, yet there is a lack of research exploring the influence of CFP geometry on internal foot loading during running. The objective of this study was to investigate the effects of CFP mechanical characteristics on forefoot biomechanics in terms of plantar pressure, bone stress distribution, and contact force transmission during a simulated impact peak moment in forefoot strike running. We employed a finite element model of the foot-shoe system, wherein various CFP configurations, including three stiffnesses (stiff, stiffer, and stiffest) and two shapes (flat plate (FCFP) and curved plate (CCFP)), were integrated into the shoe sole. Comparing the shoes with no CFP (NCFP) to those with CFP, we consistently observed a reduction in peak forefoot plantar pressure with increasing CFP stiffness. This decrease in pressure was even more notable in a CCFP demonstrating a further reduction in peak pressure ranging from 5.51 to 12.62%, compared to FCFP models. Both FCFP and CCFP designs had a negligible impact on reducing the maximum stress experienced by the 2nd and 3rd metatarsals. However, they greatly influenced the stress distribution in other metatarsal bones. These CFP designs seem to optimize the load transfer pathway, enabling a more uniform force transmission by mainly reducing contact force on the medial columns (the first three rays, measuring 0.333 times body weight for FCFP and 0.335 for CCFP in stiffest condition, compared to 0.373 in NCFP). We concluded that employing a curved CFP in running shoes could be more beneficial from an injury prevention perspective by inducing less peak pressure under the metatarsal heads while not worsening their stress state compared to flat plates.
Asunto(s)
Carrera , Zapatos , Carrera/fisiología , Humanos , Fenómenos Biomecánicos , Presión , Fibra de Carbono/química , Antepié Humano/fisiología , Análisis de Elementos Finitos , Estrés Mecánico , Soporte de Peso/fisiología , Carbono/química , Diseño de Equipo , Pie/fisiologíaRESUMEN
Partially encased concrete (PEC) has better mechanical properties as a structure where steel and concrete work together. Due to the increasing amount of construction waste, recycled aggregate concrete (RAC) is being considered by more people. However, although RAC has more points, the performance is inferior to natural aggregate concrete (NAC). To narrow or address this gap, lightweight, high-strength and corrosion-resistant CFRP can be used, also protecting the steel flange of the PEC structure. Therefore, carbon fiber reinforced polymer (CFRP) confined partially encased recycled coarse aggregate concrete columns were studied in this paper. With respect to different slenderness ratios, recycled coarse aggregate(RCA) replacement ratios, and number of CFRP layers, the performance of the proposed CFRP restrained columns are reported. The RCA replacement ratio is analyzed to be limited negative impact on the bearing capacity, generally within 6%. As for the slenderness ratio, the bearing capacity increased with it. However, wrapping CFRP significantly increased the bearing capacity. Considering the arch factor, a simple formula for calculating the ultimate strength of CFRP-confined partially encased RAC columns is developed based on EC4 and GB50017-2017. By comparison with the experimental values, the error is within 10%.