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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., (© 2024. The Author(s).)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A novel and facile method by sewing low-cost fiber electrodes on paper is proposed to fabricate electrochemical paper-based analytical devices (ePADs). Prussian Blue (PB) and Ag/AgCl were deposited on carbon fibers to prepare the working and reference electrodes. The hydrophilic carbon fiber was employed as the counter electrode. All electrodes were sewed on the paper substrate. The linear voltammetry scanning (LSV) and physical characterization results showed that the physico-chemical characteristics of the prepared electrode were maintained after sewing. As a proof of concept, the ePAD fabricating by sewing was used to detect hydrogen peroxide (H 2 O 2). The limit of detection (LOD) achieved 0.9 µM and the ePAD possessed high anti-interference ability to a variety of common ions and biological molecules. Additionally, the robustness of the ePADs against bending (error 6.2 %) manifested that the ePAD had excellent practical applicability. The good reproducibility (3.65 %) displayed by the current responses confirmed that this strategy can be profitably adopted to easily assemble ePADs in a highly flexible manner. In addition, a user-friendly reagent-free ePAD was proposed to determine the content of H 2 O 2 in real water sample without treatment. The good recovery percentage (95.7–99.7 %) demonstrated the high feasibility of the reagent-free ePAD with facile carbon fiber-sewed electrodes in the detection of H 2 O 2 from complex water samples. These results confirm that the sewing method is feasible and promising. This work provides a new insight into fabrication of highly sensitive and highly selective ePADs with fiber electrodes. [Display omitted] [ABSTRACT FROM AUTHOR]

Based on the classical grid theory and related regulations, a structure model of a fiber-wound composite gas cylinder was designed in this paper. Based on the design results, a finite element model of a fully wound composite cylinder of an aluminum alloy inner liner with a working pressure of 35 MPa was established based on the ABAQUS software, and its stress distribution under working pressure and minimum burst pressure was analyzed. According to engineering experience, the pressure tolerance of composite cylinders can be improved by proper autofrettage pressure before working pressure, so the influence of autofrettage pressure was analyzed in this paper. The optimum autofrettage pressure was selected by setting the autofrettage gradient, and damage analysis was carried out on the cylinder with nominal working pressure of 35 MPa based on the Hashin failure criterion. The results show the initial damage sequence: matrix stretching occurs before the fiber stretching, and the damage generally starts from the spiral-wound layer. The tensile damage first appears in the transition section between the head and the barrel body, and the damage of the spiral-wound layer develops from the inner layer of the wound layer to the outer layer, while the damage of the circumferentially wound layer develops from the outer layer to the inner layer. [ABSTRACT FROM AUTHOR]

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 (TiO 2 ) growth on the fiber surface. Furthermore, the material's band gap underwent modification through hydrogen calcination, thus resulting in the attainment of hierarchical black TiO 2 /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 TiO 2 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 TiO 2 /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.

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 (PDA NPs ) or only chitosan modified fiber composites. Measuring surface morphology and thermal stability of fibers found that abundant PDA NPs 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 PDA NPs /chitosan coating provides impetus for effective stress transfer. Additionally, the stable "soft-rigid" combination of chitosan and PDA NPs 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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Carbon fiber-reinforced polymer composites (CFRPs) have gained widespread usage due to their promising physiochemical properties, while this causes large amounts of waste CFRPs worldwide. In this study, carbon fibers were successfully recovered from waste CFRPs through the pyrolysis-oxidation method, and the recovered fibers were reused in remanufacturing the secondary generation CFRPs. Moreover, the individual and interactive effects of pyrolysis-oxidation recovering parameters on the mechanical strength of the resulting remanufactured CFRPs (reCFRPs) were investigated. The recovered carbon fibers displayed surface chemical structures similar to virgin fibers but with high contents of oxygen-containing bonds. The tensile strength retention (TSR) of the reCFRPs was primarily influenced by oxidation temperature. Notably, a higher oxidation temperature, especially exceeding 560 °C, amplified the impact of oxidation duration on the TSR value. Similarly, concerning interlaminar shear strength retention (ISSR), the oxidation stage had a more substantial effect compared to the pyrolysis stage. As the oxidation temperature increased from 500 °C to 600 °C, the ISSR value initially increased and then decreased, irrespective of variations in pyrolysis parameters. Additionally, through integrating the response surface methodology (RSM) analysis and multi-island genetic algorithm (MIGA) global optimization, three recovery strategies, along with the corresponding processing parameters, were proposed to meet diverse requirements. The conclusions could provide valuable insights for optimizing the recovery and reuse of carbon fibers from waste CFRPs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Short carbon fiber (SCF) reinforced polymer composites are expected to possess outstanding biotribological and mechanical properties in certain direction, while the non-oriented SCF weakens its reinforcing effect in the matrix. In this work, high-oriented SCF was achieved during nozzle extrusion, and then SCF reinforced polyether-ether-ketone (PEEK) composites were fabricated by fused deposition modeling (FDM). The concrete orientation process of SCF was theoretically simulated, and significant shear stress difference was generated at both ends of SCF. As a result, the SCF was distributed in the matrix in a hierarchical structure, containing surface layer I, II and core layer. Moreover, the SCF was oriented highly along the printing direction and demonstrated a more competitive orientation distribution compared to other studies. The SCF/PEEK composites showed a considerable improvement in wear resistance by 44 % due to self-lubricating and load-bearing capability of SCF. Besides, it demonstrated enhancements in Brinell hardness, compressive and impact strength by 48.52 %, 16.42 % and 53.64 %, respectively. In addition, SCF/PEEK composites also showed good cytocompatibility. The findings gained herein are useful for developing the high-oriented SCF reinforced polymer composites with superior biotribological and mechanical properties for artificial joints., Competing Interests: Declaration of competing interest With submitting the manuscript, the authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Carbon-fiber custom dynamic orthoses are used to improve gait and limb function following lower limb trauma in specialty centers. However, the effects of commercially available orthoses on center of pressure progression and patient perception of orthosis smoothness during walking are poorly understood., Methods: In total, 16 participants with a unilateral lower extremity traumatic injury underwent gait analysis when walking without an orthosis, and while wearing monolithic and modular devices, in a randomized order. Device alignment, stiffness, participant rating of perceived device smoothness, center of pressure velocity, and ankle zero moment crossing were assessed., Findings: The modular device was approximately twice as stiff as the monolithic device. Alignment, smoothness ratings, peak magnitude of center of pressure velocity, and zero moment crossing were not different between study devices. The time to peak center of pressure velocity occurred significantly later for the modular device compared to the monolithic and no orthosis conditions, with large effect sizes observed., Interpretation: Commercially available orthoses commonly used to treat limb trauma affect the timing of center of pressure progression relative to walking without an orthosis. Despite multiple design differences, monolithic and modular orthoses included in this study did not differ with respect to other measures of center of pressure progression. Perceived smoothness ratings were approximately 40% greater with the study orthoses as compared to previous studies in specialty centers, which may be due to a more gradual center of pressure progression, as indicted by lower peak magnitude of center of pressure velocity with both study orthoses., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

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%., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Wang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Obtaining lignin-based graphite-like microcrystallites at a relatively low carbonization temperature is still very challenging. In this work, we report a new method based on condensed structures, for regulating graphite-like microcrystalline structures via the incorporation of 4,4'-diphenylmethane diisocyanate (MDI) into the main structure of lignin. The effects of MDI on the thermal properties of lignin and the graphite-like microcrystalline structure of lignin-based ultrafine carbon fibers were extensively studied and investigated. The incorporation of MDI decreased the thermal stability of lignin, increased the carbon yield and enhanced the formation of graphite-like microcrystallites, which are beneficial for reducing energy consumption during the preparation of lignin-based carbon fibers. The modified lignin-based ultrafine carbon fibers (M-LCFs) demonstrated satisfactory electrochemical performance, including high specific capacitance, low charge transfer resistance, and good cycle performance. The M-LCFs-3/2 electrode had a specific capacitance of 241.3 F g -1 at a current density of 0.5 A g -1 , and a residual ratio of 90.2 % after 2000 charge and discharge cycles. This study provides a new approach to control the graphite-like microcrystalline structure and electrochemical performance while also optimizing the temperature., Competing Interests: Declaration of competing interest I would like to declare on behalf of my co-authors that we have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Nanoparticle-containing sizing agents are essential for the overall performance of high-quality carbon fiber (CF) composites. However, the uneven dispersion of nanoparticles often leads to agglomeration on the surface of CF after sizing, consequently diminishing the material properties. In this study, the properties of cellulose nanofibers (CNFs) that can respond to magnetic and electric fields were utilized to achieve three-dimensional to one-dimensional orientations in CFs containing sizing agents. Cobalt ferrite (CoFe 2 O 4 ) was utilized to enhance the response of CNFs to a magnetic field, and subsequently, it was combined with an electric field to attain a higher degree of orientation. The occurrence of nanoparticle agglomeration is diminished on CF surface, while establishing a structured network. The flexural strength and thermal conductivity of CF composites treated with CoFe 2 O 4 self-assembled CNF sizing agent exhibit an increase of 54.23 % and 57.5 %, respectively, compared to those of desized CF composites, when subjected to magnetic and electric fields. Consequently, the approach can depolymerize the nano-fillers within the sizing agent and orient it into the carbon fiber under the influence of magnetic and electric fields, effectively improving the mechanical properties and thermal conductivity of the composite material., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Drug-impaired driving poses a significant risk of collisions and other hazardous accidents, emphasizing the urgent need for simple and rapid roadside detection methods. Oral fluid, as an easily collectible and non-invasive test material, has gained widespread use in detecting drug-impaired driving. In this study, we have devised a method for direct sampling using a carbon fiber bundle combined with flame ionization mass spectrometry. The essence of this method lies in the synergy between the adsorption properties of carbon fiber and the plasma characteristics of the flame. Leveraging the strong adsorption capabilities of the carbon fiber bundle allows for the use of a minimal sample size (<100 μL) during sampling, presenting a distinct advantage in the roadside inspection and sampling process. Throughout the flame ionization process, proteins and salts within the oral fluid matrix adhere well to the carbon fiber bundle, while small molecule targets can be efficiently desorbed and react with charged species in the flame, leading to ionization. The results demonstrate the successful development of carbon fiber-sampling combined flame ionization mass spectrometry, capable of qualitative and quantitative analysis of drugs in oral fluid without the need for sample pre-treatment. Its quantitative capabilities are sufficient for real sample detection, providing an effective analytical method for the roadside detection of drugs in oral fluids., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The electro-Fenton (EF) based on gas-diffusion electrodes (GDEs) reveals promising application prospective towards recalcitrant organics degradation because such GDEs often yields superior H 2 O 2 generation efficiency and selectivity. However, the low efficiency of Fe 2+ /Fe 3+ cycle with GDEs is always considered to be the limiting step for the EF process. In this study, activated carbon fiber (ACF) was firstly employed as co-catalyst to facilitate the performance of antibiotic cefaclor (CEC) decomposition in EF process. It was found that the addition of ACF co-catalyst achieved a rapid Fe 2+ /Fe 3+ cycling, which significantly enhanced Fenton's reaction and hydroxyl radicals ( • OH) generation. X-ray photoelectron spectroscopy (XPS) results indicated that the functional groups on ACF surface are related to the conversion of Fe 3+ into Fe 2+ . Moreover, DMSO probing experiment confirmed the enhanced • OH production in EF + ACF system compared to conventional EF system. When inactive BDD and Ti 4 O 7 /Ti anodes were paired to EF system, the addition of ACF could significantly improve mineralization degree. However, a large amount of toxic byproducts, including chlorate (ClO 3 - ) and perchlorate (ClO 4 - ), were generated in these EF processes, especially for BDD anode, due to their robust oxidation capacity. Higher mineralization efficiency and less toxic ClO 4 - generation were obtained in the EF + ACF process with Ti 4 O 7 /Ti anode. This presents a novel alternative for efficient chloride-containing organic removal during wastewater remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Titanium as the leading implant material in locked plating is challenged by polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK), which became the focus of interest of researchers and manufacturers in recent years. However, data on human tissue response to these new implant materials are rare. Osteosynthesis plates and peri‑implant soft tissue samples of 16 healed proximal humerus fractures were examined (n = 8 CFR-PEEK, n = 8 titanium). Soft tissue was analyzed by immunohistochemistry and µCT. The entrapped foreign bodies were further examined for their material composition by FTIR. To gain insight into their origin and formation mechanism, explanted and new plates were evaluated by SEM, EDX, profilometry and HR-CT. In the peri‑implant soft tissue of the CFR-PEEK plates, an inflammatory tissue reaction was detected. Tissues contained foreign bodies, which could be identified as tantalum wires, carbon fiber fragments and PEEK particles. Titanium particles were also found in the peri‑implant soft tissue of the titanium plates but showed a less intense surrounding tissue inflammation in immunohistochemistry. The surface of explanted CFR-PEEK plates was rougher and showed exposed and broken carbon fibers as well as protruding and deformed tantalum wires, especially in used screw holes, whereas scratches were identified on the titanium plate surfaces. Particles were present in the peri‑implant soft tissue neighboring both implant materials and could be clearly assigned to the plate material. Particles from both plate materials caused detectable tissue inflammation, with more inflammatory cells found in soft tissue over CFR-PEEK plates than over titanium plates. STATEMENT OF SIGNIFICANCE: Osteosynthesis plates are ubiquitously used in various medical specialties for the reconstruction of bone fractures and defects and are therefore indispensable for trauma surgeons, ENT specialists and many others. The leading implant material are metals such as titanium, but recently implants made of polymers such as carbon fiber-reinforced polyetheretherketone (CFR-PEEK) have become increasingly popular. However, little is known about human tissue reaction and particle generation related to these new implant types. To clarify this question, 16 osteosynthesis plates (n = 8 titanium and n = 8 CFR-PEEK) and the overlying soft tissue were analyzed regarding particle occurrence and tissue inflammation. Tissue inflammation is clinically relevant for the development of scar tissue, which is discussed to cause movement restrictions and thus contributes significantly to patient outcome., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

The application of carbon fiber in cement matrix has some disadvantages, such as poor dispersion and poor interfacial adhesion. In order to improve the interaction between carbon fiber and cement matrix and improve the properties of cement-based composites, carbon fiber was modified by electrophoretic deposition of nano-graphene oxide (GO). In this paper, the effects of doping CF into the cement matrix before and after GO modification are studied comparatively in terms of electrical conductivity, electrothermal warming effect, and pressure-sensitive properties of the cement matrix. It was found that the GO-modified CF reduces both the electrical resistivity of cementitious composites and the required level of fiber incorporation compared to CF. The percolation threshold is 0.7 wt% for CF and 0.5 wt% for GO-CF. The GO-modified CF is more effective than CF as a conductive filler to enhance the electrothermal warming performance of the cement matrix. When the GO-CF doping rate is 0.5%, the specimen temperature increases most rapidly, and the temperature rise value reaches a maximum of up to 30.45 °C, which is twice that of the CF group. When the fiber content is 0.7%, the pressure sensitivity of the sample was the best. When the fiber content is 0.5%, GO-CF can improve the pressure sensitivity of cement mortar specimens, and increase the resistance change rate of the cement mortar specimens by 5.7%. [ABSTRACT FROM AUTHOR]

Civil infrastructures are constantly exposed to environmental effects that can contribute to deterioration. Early detection of damage is crucial to prevent catastrophic failures. Structural Health Monitoring (SHM) systems are essential for ensuring the safety and reliability of structures by continuously monitoring and recording data to identify damage-induced changes. In this context, self-sensing composites, formed by incorporating conductive nanomaterials into a matrix, offer intrinsic sensing capabilities through piezoresistivity and various conduction mechanisms. The paper reviews how SHM with self-sensing materials can be applied to civil infrastructure while also highlighting important research articles in this field. The result demonstrates increased dissemination of self-sensing materials for civil engineering worldwide. Their use in core infrastructure components enhances functionality, safety, and transportation efficiency. Among nanomaterials used as additions to produce self-sensing materials in small portions, carbon nanotubes have the most citations and, consequently, the most studies, followed by carbon fiber and steel fiber. This highlight identifies knowledge gaps, benchmark technologies, and outlines self-sensing materials for future research. [ABSTRACT FROM AUTHOR]

With the rapid development of wireless communication technologies and the miniaturization trend in the electronics industry, the reduction of electromagnetic interference has become an important issue. To solve this problem, a lot of attention has been focused on polymer composites with combined functional fillers. In this paper, we report a method for creating an acrylonitrile butadiene styrene (ABS) plastic composite with a low amount of conductive carbon and magnetic fillers preparation. Also, we investigate the mechanical, thermophysical, and electrodynamic characteristics of the resulting composites. Increasing the combined filler amount in the ABS composite from 1 to 5 wt % leads to a composite conductivity growth of almost 50 times. It is necessary to underline the temperature decrease of 5 wt % mass loss and, accordingly, the composite heat resistance reduction with an increase in the combined filler from 1 to 5 wt %, while the thermal conductivity remains almost constant. It was established that electrodynamic and physical–mechanical characteristics depend on the agglomeration of fillers. This work is expected to reveal the potential of combining commercially available fillers to construct effective materials with good electromagnetic interference (EMI) protection using mass production methods (extrusion and injection molding). [ABSTRACT FROM AUTHOR]

AbstractCarbon fiber reinforced thermosetting resin composites (CFRTRC) have drawn great attention in automotive, aerospace, wind turbine blades and other important industry sectors, due to their characteristics of high specific strength and good corrosion resistance. With the extensive use of CFRTRC, the waste composite generated and accumulated is a problem that must be tackled. Thus, the efficient recycling of carbon fibers from CFRTRC is essential. There are many recycling methods; among them the thermal recycling methods have attracted great interest for the CFRTRC in general. The thermal recycling methods of CFRTRC are reviewed in this paper, listed in the order of publication, and are classified into pyrolysis method, fluidized bed method, microwave pyrolysis method and superheated steam method. The advantages and disadvantages of the thermal recycling methods are described in detail. This paper describes in detail the thermal recycling methods of CFRTRC, which, we suggest, will contribute to the sustainable development of the composite industry. [ABSTRACT FROM AUTHOR]

The article presents analysis of mechanical properties of specimens fabricated by fused deposition modelling (FDM). The four of considered materials are the well-known 3D printing filaments i.e., polylactide (PLA), Nylon 12 (PA12), acrylonitrile butadiene styrene (ABS), polyethylene terephthalate glycol (PET-G). The other four materials considered are carbon-fiber composites not described in the literature, i.e. polylactide with carbon fiber (PLACF), Nylon 12 with carbon fiber (PA12-CF), acrylonitrile butadiene styrene with carbon fiber (ABS-CF), polyethylene terephthalate glycol with carbon fiber (PETG-CF). The paper describes how the specimens were designed, printed, subjected to static tensile tests and static bending tests, and examined using microscopy. The obtained data uses to select the optimum material for the rapid manufacturing of lower limb orthoses. Carbon composites were found to have better mechanical properties of their base material, but the fabrication of composite samples is much more time consuming, for the reason that the manufacturing process is not stable. [ABSTRACT FROM AUTHOR]

Our objective is to achieve the societal implementation of the Circular Economy Program for Automobile Carbon Fibers. This involves recycling carbon fibers sourced from carbon fiber reinforced plastics/carbon fiber reinforced thermoplastics (CFRP/CFRTP) discarded from automobiles and reintegrating them into the manufacturing processes of automobiles. Although, the existing carbon fiber recycling technology recycles the carbon fiber into a finely chopped state; it is not the original continuous carbon fiber product. A novel recycling technology is elucidated herein, referred to as the electrolytic sulfuric acid method (ESAM). The ESAM recycles carbon fibers by decomposing only the resin component of CFRP/CFRTP into CO2 and water using oxidative active species generated by electrolytic sulfuric acid. This method can (1) be applied to all resins, (2) maintains strength of the recycled carbon fibers, and (3) regenerates continuous carbon fibers. Moreover, it is the only technology applicable to CFRP pressure tanks. The successful recycling of continuous carbon fiber from pressure tanks has been achieved, enabling the production of new tanks and unidirectional CFRTP tape. This technology recycles the original continuous carbon fiber product, thus enabling a "close" resource circulation cycle. We have not yet confirmed the number of times recycling can be performed. However, according to the method described in this paper, the recycling process can yield continuous carbon fibers without a decrease in physical properties. Therefore, theoretically, it becomes possible to recycle indefinitely and revert the fibers to their original state, provided that the strength reduction during product use is not a significant consideration. [ABSTRACT FROM AUTHOR]

One of the ways to improve durability is the addition of short discrete fiber into the concrete, which improves properties like fracture toughness, flexural strength, thermal shock, tensile strength, spalling resistance and impact resistance. The main advantage of fiber within the concrete is to bear the tensile stress and to prevent crack propagation. In this paper, the carbon fiber and basalt fiber reinforced concretes were prepared and the compressive strength was examined. Initially, the first step has been made with ground granulated blast furnace slag (GGBS) in order to strengthen the concrete's compressive strength through carbon and basalt fiber reinforcement. The compressive strength has been measured within the interval of 7 days, 14 days and 28 days on cube casted concrete M25 and M35 grades. The results are obtained and compared to obtain the strongest mixture proportion. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Synthetic Crystals is the property of Journal of Synthetic Crystals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Dynamic and buckling of a composite beam reinforced with a combination of carbon and aramid fibers is studied in this paper. The beam is under a thermal gradient through the thickness. Timoshenko beam is made of a polymer matrix (epoxy resin) reinforced with layers of high-strength carbon and high-toughness aramid fibers in order to create a balance between stiffness and toughness and create a type of structural composite beam with excellent strength and toughness. The mechanical and thermal properties of the hybrid composite beams are obtained based on the mixed law method. The equations of motion are extracted based on the Hamilton principle and then solved by the generalized differential quadrature method (GDQ). In this study, a thermal gradient is applied to the beam and then the vibration and buckling response of this hybrid composite beam are studied. The main contribution of this paper is the vibration and buckling responses of a hybrid composite structure strengthened by carbon and aramid fibers. The effect of the hybrid ratio as well as the stacking sequence on the free vibrations and critical buckling load are presented. The fundamental frequency and critical buckling load are largely affected by the stacking sequence. The conclusions show that the use of aramid fibers in the composite beam reinforced with carbon fibers decreases the natural frequency as well as the critical buckling load of the beam. The conclusions also show that for the symmetric hybrid composite beam, despite the critical buckling temperature being the same, the critical buckling load is different and depends on the location of the fibers. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As a multifunctional filler, carbon materials play an important role in enhancing the comprehensive properties of polypropylene composites. However, it is an important task to balance the relationship between the amount of different carbon materials and the formability and functionality of composite products. In this paper, the properties of carbon fiber, carbon nanotube and graphene, and the effects of these carbon materials on the mechanical, thermal and electrical properties of polypropylene-based multi-scale composites are discussed respectively. It is pointed out that it is a challenging research direction to prepare polypropylene composites filled with high content and hybrid carbon materials by melt deposition 3D printing process in the future. [ABSTRACT FROM AUTHOR]

This paper aims to explore the potential of carbon nanotubes (CNTs) in enhancing the structural capability and multifunctionality of carbon fiber composites in aerospace applications, primarily by focusing on interfacial applications. The conventional method of dispersing CNTs in a matrix is not fully efficient in exploiting the mechanical and multifunctional performance of CNTs. Hence, the use of CNTs at the interface or as a coating on the surface of carbon fibers has been suggested as a means of achieving multifunctionality, in addition to enhanced mechanical performance. The paper presents an overview of the various processes for growing CNTs on carbon fiber surfaces and examines the effects of CNT geometry and growth parameters on the properties of grafted fibers and their composites. Furthermore, it discusses the potential improvements in thermal and electrical conductivity achievable by incorporating CNTs at the interface, as well as the benefits of using CNTs as a sizing layer for carbon fibers, including enhanced fracture toughness and resistance to delamination. Highlights: Comprehensive study of interface engineering in carbon fibers and Carbon Fibre Reinforced Plastic (CFRPs) using carbon nanotubes (CNTs).Improved transverse mechanical properties and overall thermal and electrical properties.Multifunctional applications possible with the use of CNT.Both experimental and numerical studies reviewed. [ABSTRACT FROM AUTHOR]

Optimization of structural elements via composition of different components is a significant scientific and practical point-of-view problem aimed at obtaining more economical and environmentally friendly solutions. This paper presents the results of a static work analysis of small-size laminated veneer lumber (LVL) beams reinforced by a Carbon Fiber Reinforced Polymer (CFRP) sheet. The nominal dimensions of LVL beams were 45 × 45 × 850 mm, and 0.333- and 0.666-mm thick reinforcement layers were used. The reinforcement was applied on opposite sides of the cross section obtaining a sandwich-type structure. An epoxy resin was used as a bonding layer. The bending tests were conducted in the so-called four-point bending static scheme in edgewise and flatwise conditions. The results of experimental tests confirmed the validity of this combination of materials. The highest load-bearing capacity was obtained for configuration, where CFRP sheets with a thickness of 0.666 mm were placed on the sides of the core, parallel to the direction of loading and the veneer's grain in the core. The increase in this case was up to a maximum of 57% compared to the core alone. The highest bending stiffness increase, 182% compared to the core alone, involves placing two layers of sheets perpendicular to the direction of loading, i.e., on the upper and lower surfaces. The presented novel sandwich structure can be competitive against traditional steel and reinforced concrete elements in civil engineering and can be utilized as beams or slabs. [ABSTRACT FROM AUTHOR]

Chemical grafting is commonly employed to functionalize carbon fiber (CF) surface to enhance the interfacial properties of CF reinforced polymer composites (CFRP) by forming a robust interface. However, an overly rigid interface layer can result in relatively poor interface toughness. To balance interfacial strength and toughness, this paper proposes an effective method to simultaneously strengthen and toughen the interface of CF/epoxy composites by grafting branched polyethyleneimine (PEI) on CF surface using hexachlorophosphazene (HCCP) as active intermediate, which features a rigid ring structure and six active P‐Cl groups. The introduction of PEI provided a large number of amine and imine groups on CF surfaces, which were contributive to improving surface wettability and reactivity of CF, thus resulting in strong chemical bonding between CF and epoxy matrix. Additionally, the long and flexible molecular skeleton of PEI constructed a rigid‐flexible composite interface, which could effectively reduce stress concentration and absorb impact energy. After surface modification with PEI, the interfacial shear strength and fracture toughness of CF/epoxy composite were increased to 89.9 MPa and 200.3 J m−2, by 64.3% and 149.7%, respectively, in compared with desized CF reinforced epoxy composites. Highlights: A rigid‐flexible interface was constructed between CF and epoxy resin.The interfacial strength and toughness of CFRP were synergistically improved.IFSS and interfacial toughness increased by 64.3% and 149.7%, respectively. [ABSTRACT FROM AUTHOR]

Highlights The interface property of carbon fiber/matrix materials is a key factor influencing the service life of composites. In this paper, our group facilely in‐situ grew zeolitic imidazolate framework‐8 (ZIF‐8) onto the carbon fiber (CF) surface by using branched polyethyleneimine (BPEI) as coupling agent to simultaneously enhance the interface and mechanical performances of CF/epoxy composite. The successful growth of ZIF‐8 nanocrystals onto carbon fiber was confirmed by FT‐IR, XPS, TGA, XRD, Raman, and SEM. After growth of ZIF‐8, the surface morphology for CF grafted with ZIF‐8 (CF‐ZIF‐8) was greatly changed and the surface energy for modified carbon fiber increased from 28.7 mN/m for the untreated CF to 55.8 mN/m. As a result, the interfacial shear strength (IFSS) of CF‐ZIF‐8/epoxy composite enhanced by 103.4%, indicating a significant improvement of interface property of composite. Moreover, the interlaminar shear strength (ILSS) and bending strength also have 37.8% and 23.3% improvement because of the synergistic effect of BPEI and ZIF‐8 compared to the untreated CF/epoxy composite. This work furnishes a facile and efficient strategy for developing high‐performing structural composite materials with excellent interface property. ZIF‐8 was in‐situ grown on CF to improve the interface property of composite. Significant improvements on IFSS, ILSS, and bending strength. The mechanism for improving the performances of composite was proposed. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of carbon fiber and graphite on the cyclic electrothermal performance of geopolymers (inorganic polymers). It was observed that carbon fibers, graphite, and the carbon fiber/graphite composite could form a stable conductive network at low voltage (3 V). However, under high voltages (9 and 12 V), the current of the geopolymer exhibited a peak shape in the first cycle, with higher voltages resulting in larger peak values and decreased conductivity in subsequent cycles. While graphite improved electrical and thermal conductivity, it weakened the microstructure, leading to an increase in microcracks and voids, and a reduction in the strength of geopolymers. The cumulative energy during the electrothermal process was calculated. The failure mechanism of the conductive network in the geopolymer during cyclic electrical heating was explained, highlighting the disruptive effect of gel shrinkage due to water loss on conductive networks. [ABSTRACT FROM AUTHOR]

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Carbon fiber (CF) possesses inherent properties of low density, high strength, and environmental stability. Its high aspect ratio and knittability enable the formation of flexible conductive networks. Old corrugated container (OCC) is rich in cellulose and hemicellulose, rendering them flexible and exhibiting a low coefficient of thermal expansion. In this paper, CF/OCC/PVA flexible conductive films were prepared using polyvinyl alcohol (PVA) as the matrix, CF as the conductive filler and OCC as the flexible support material. Firstly, the coupling agent was grafted on the surface of CF to enhance their surface activity, improve the dispersion of CF in solution and the chemical bonding of CF to the matrix. Subsequently, sizing nanoparticles were applied to increase the roughness of the CF surface. This served to increase the volume of the conductive network and enhance the mechanical interlocking between CF and PVA. The results show that the two-step combined modification strategy have a significant positive impact on the interfacial chemical activity, contact angle, and roughness of CF. Moreover, it leads to notable improvements in various properties of the conductive film materials. This finding is relevant for the preparation of CF reinforced other matrix materials as well as for expanding the special properties and application value of CF conductive thin film materials. [Display omitted] • Low-cost flexible conductive films were produced using CF and OCC as reinforcing materials. • The improvement of CF surface activity builds a uniform and dense conductive network. • Silane coupling agents and nanoparticles work together to create an interfacial buffer layer. • The conductive film now exhibits significantly improved electrical and mechanical properties. [ABSTRACT FROM AUTHOR]

Carbon fiber reinforced thermoplastic composites have such advantages as low density, high strength, high temperature resistance, impact resistance, and good ductility, but due to the density difference between carbon fibers and resin fibers, it is difficult to mix them uniformly. Hence, it is difficult to prepare the composites with the uniform properties. In order to solve this problem, a preparation process based on solid phase mixing of carbon and resin fibers by suspension method is proposed in this paper. The carbon fiber reinforced thermoplastic composites (CFRTPs) can be prepared by dispersing carbon fibers of a certain length (~50 mm) and resin fibers in suspension through ultrasound‐assisted and churn‐combing methods. The effects of carbon fiber length, content and molding process on the mechanical properties of the CFRTPs were studied. The results show that the carbon fiber content and length are the main factors affecting the mechanical properties as well as void ratio of CFRTP. The performance of composites is significantly improved with the increase of carbon fiber length. While the length of carbon fiber is 50 mm and the content is 30 wt%, the prepared CFRTP has the best performance, with the tensile strength of 182.1 MPa, the bending strength of 354.3 MPa, the impact strength of 67.2 KJ·m−2, and the material void ratio of 0.65%. The study shows that the suspension method is feasible for the preparation of the CFRTPs. It is beneficial to improve production efficiency and decrease cost of production for the CFRTPs. Highlights: Carbon fiber reinforced thermoplastic composites can be prepared by dispersing carbon fibers of a certain length (~50 mm) and resin fibers in suspension through ultrasound‐assisted and churn‐combing methods.Through the cooling‐high pressure molding process, the porosity of CFRTP is reduced and the mechanical properties of CFRTP are improved.The tensile strength, bending strength, and notch‐free impact strength properties of CFRTP are best when the carbon fiber content is 30% and the CF length is 50 mm.The method is characterized by simple process, low cost and high mechanical properties. [ABSTRACT FROM AUTHOR]