As formaldehyde releasing agent, hexamethylenetetramine (HMT) has been widely applied to resorcinol formaldehyde resin (RF) based hierarchically micro-mesoporous carbon nanospheres (HMCNs) because it can control over the resin polymerization process. However, the role of HMT in regulating the HMCNs pore structure, especially the micropore structure, has not yet been clarified. Herein, HMCNs with tunable hierarchical micromesopores architecture were designed and the influences of HMT on pore structure from a molecular perspective were elucidated systematically. The results indicate that HMT not only decomposes into formaldehyde, which polymerizes with resorcinol to form RF resins but can generate nitrogen-containing intermediates in resins skeleton. These generate nitrogen-containing intermediates tend to promote the structural loosening and contribute to the micropore volume as well as nitrogen doping during pyrolysis. A more thorough decomposition of HMT tends to promote the formation of a readily graphitizable RF resin structure with abundant soft templates, resulting in the HMCNs with more lattice defects, a narrow micropore aperture and large mesopore volume. As a demonstration of their versatility, the obtained HMCNs with high specific surface area and abundant porosity exhibit outstanding electrochemical performance when used as separator modifiers in lithium-sulfur batteries (LSBs). Specifically, the final batteries achieve a high initial specific capacity of 970.9 mAh g(-1) with an excellent capacity retention of 80% at 500 cycles at 1C. Our work provides a guidance for precisely designing the pore configuration of functional HMCNs materials.

3D-printed continuous carbon fiber-reinforced polyamide (CCF/PA) composites suffered challenges in achieving strong interfacial adhesion due to rapid melting-cooling and limited impregnation pressure during layer-by-layer deposition. To address this, a thermal oxidation activation strategy was proposed to enhance the mechanical properties of 3D-printed composites by precisely controlling the interfacial evolution behavior of carbon fibers (CF). The interaction between the physical structure and chemical polarity of CF and their effects on the mechanical properties of 3D-printed CCF/PA composites were systematically examined. The results indicate that the mechanical properties of 3D-printed composites are collectively governed by the interfacial morphology of CF and graphite-induced microdefects. Under the constrained thermal and pressure conditions of 3D printing, the surface chemical polarity critically influenced interfacial construction efficiency. The controlled oxidation has introduced surface defects, altering the stress-transmission pathways and their effectiveness. Furthermore, the orientation and content of the graphite structure on the carbon fiber surface determine the conversion efficiency of the mechanical properties in 3D-printed composites. This study illustrates the mechanism by which CF interfacial evolution contributes to the mechanical behavior of 3D-printed CCF/PA composites, providing insights for interfacial design in additive manufacturing of high-performance composites.

Aiming at the growing requirements for long-term storage and service reliability of solid rocket motors, this work adopted a blended aqueous emulsion of ethylene acrylic acid copolymer (EAA) and polyethylene wax (PEW) as a carbon fiber sizing agent to optimize the interfacial performance of EPDM matrix composites. After sizing modification, the interfacial peel strength was greatly elevated from 1.22 kN/m to 2.36 kN/m relative to pristine carbon fiber. SEM characterization demonstrated that the binary sizing agent uniformly covered the fiber surface, facilitated the infiltration of EPDM into fiber bundles, reduced interfacial voids and enhanced interfacial compactness. Molecular dynamics simulation revealed the enhancement mechanism: sizing molecules constructed a modulus gradient to relieve interfacial stress concentration, and PEW moderated the polarity of EAA carboxyl groups, improving the compatibility between sizing agent and EPDM. Meanwhile, the sizing treatment slightly reduced the mass ablation rate and strengthened the bonding between carbon fiber and ablation char layers, forming an integrated protective residue. This eco-friendly facile strategy effectively improves the interfacial bonding and thermal protection reliability of EPDM/carbon fiber composites, offering a feasible route for preparing high-performance thermal insulation materials.

A comparative study of the microstructure and sodium storage behaviors of three special hard carbons (HCs) derived from polyacrylonitrile fibers (PANCFs), mesophase pitch fibers (MPCFs) and rayon fibers (RCFs) are carried out for the first time. The results reveal that the MPCF-based HC presents the highest crystallinity, while the amorphous degree and defect contents rise in sequence for the PANCF-based HC and RCF-based HC. Moreover, the RCF-based HC has the richest oxygen functional groups. The electrochemical performance evaluation indicates that the RCF-based HC exhibits much prolonged plateau characteristic below 0.1 V, reaping the highest reversible capacity of 310.8 mAh g- 1 and excellent cycling stability (98.9 % after 200 cycles). This study provides a rewarding attempt for the exploitation of carbon fiber-based HCs in sodium-ion batteries.

The sluggish kinetics of oxygen evolution reaction (OER) is one of the critical challenges for electrochemical water splitting. Rational design of single atom on metal-support interactions (MSI) using deposition method is essential for electrocatalytic materials. Herein, we report the single-atomic-site and cluster-site iridium stabilized on high-entropy oxides (FeCoNiCrMoOx) with deposition method using choline chloride/urea deep eutectic solvent (ChCl/U). The resulting Ir single atoms and clusters exhibit an average interatomic distance of approximately 0.77 nm. Ir1&n-FeCoNiCrMoOx delivers an ultralow overpotential of 193 mV at a current density of 100 mA·cm-2, and a long-term stability over 240 h for OER by precisely regulating the local coordination environments of the active sites in catalyst. DFT calculations reveal that closely distance single atoms and clusters exhibit stronger interactions with the high-entropy substrate. These strong interactions lead to a shift in the rate-determining step, and Ir1&n-FeCoNiCrMoOx demonstrates the lowest theoretical OER overpotential. This work introduces DES as an effective electrochemical deposition method with synthesizing closely spaced single atoms and clusters for superior OER activity.

This study presents the fabrication of internally porous polyacrylonitrile carbon fibers (PCFs) to enhance the thermal insulation property in ethylene propylene diene monomer (EPDM) composites. By employing the precursor fibers without hot-stretching, PCFs with unique skin-core structure and abundant internal pores are obtained. These pores, combined with disordered carbon texture, significantly increase electrical resistivity by 56.4 % compared to conventional carbon fibers, while maintaining acceptable mechanical property and high carbon content. The PCF/EPDM composite exhibits prominently declined thermal conductivity (0.770 W/(m & sdot;K)) and moderate ablation resistance, making it a promising candidate for heat shielding materials in solid rocket motors. This work offers a new strategy to balance thermal insulation and ablation resistance in high-performance composites.

The interfacial properties of carbon fiber-reinforced thermoplastics are governed by carbon fiber surface characteristics. While the interfacial mechanisms in thermoset composites have been extensively investigated, their thermoplastic counterparts have received comparatively less attention. This research implements a cross-scale methodology integrating macroscopic experiments and molecular dynamics (MD) simulations to elucidate interfacial mechanisms between polyamide 6 (PA6) and two types of carbon fibers with distinct surface states: dry-jet wet-spun carbon fiber (DSCF) and wet-spun carbon fiber (WSCF). Experimental results revealed a notably 55.74 % higher interfacial shear strength (IFSS) in DSCF/PA6 composites (63.20 MPa) compared with WSCF/ PA6 systems (40.58 MPa). Through comprehensive microscopic analysis and computational modeling, we found that the enhanced interfacial performance of DSCF stems from its higher concentration of oxygen-containing functional groups, which promote the formation of a more robust hydrogen bond network with PA6 molecules. Building upon this fundamental understanding, we proposed a mesoscale optimization strategy focused on hydrogen bond network regulation. Implementing controlled cooling during composite molding enhanced PA6 crystallinity, leading to a 26.74 % increase in the IFSS of DSCF/PA6 to 80.10 MPa. This work not only clarifies the critical role of hydrogen bonding in interfacial reinforcement but also presents a practical multiscale design framework for DSCF/PA6 composites. The findings offer valuable insights for carbon fiber selection and interface engineering, contributing significantly to the development of advanced carbon fiber-reinforced thermoplastic materials.

3D printing of continuous fiber-reinforced thermoplastic composites has attracted considerable attention for fabricating complex structures rapidly without molds. However, the mechanical properties of 3D printed composites suffered from low fiber content and high porosity, which hindered their practical application. To address these challenges, the study proposed a novel method to prepare continuous carbon fiber/polyamide (CCF/PA) pre-impregnated filaments via viscosity-controlled solution impregnation. A custom-designed solution impregnation device was developed to produce filaments with high fiber content, low porosity, and outstanding mechanical properties. The preparation process was optimized using multi-objective optimization to validate the printing reliability and superiority. The optimized filaments and their composites exhibited exceptional properties with a fiber content over 65 % and tensile strengths over 1800 MPa and 730 MPa, respectively. Additionally, a systematic investigation was conducted to analyze the micro-impregnation structures and fiber-matrix interfacial characteristics under controlled processing parameters, including temperature, speed, and concentration. This innovative approach demonstrates promising potential for improving the properties of 3D-printed CCF/PA composites and expanding their applications in the industry.

The andante electrocatalytic conversion and grievous shuttle effect of lithium polysulfides (LiPSs) lead to stagnant applications of lithium-sulfur (Li-S) batteries. Plentiful catalysts such as ZnS-FeS heterostructures have been employed to solve those problems. However, the mechanism of this heterostructures on sulfur reduction reaction (SRR) especially the conversion of Li2S2 to Li2S (Li2S2RR) and Li+ migration has not been revealed. Herein, a ZnS-FeS heterostructures embedded in hierarchical porous carbon (ZnS-FeS/HPC) was demonstrated that can act as effective catalyst to accelerate Li2S2RR and promote the Li+ diffusion simultaneously. This improvement can be attributed to the moderate adsorption energy and lower d-band center of the heterostructures to reaction intermediates. Moreover, with both homogeneous porous structure and abundant polarity sites, the modified separator using ZnS-FeS/HPC was endowed with selectivity to promote uniform Li+ flux and migration, as well as impede the dendritic Li growth and LiPSs shuttling. Benefited from above advantages, the batteries exhibited superior initial capacity of 1674.7 mAh/g (current density: 0.2C). Even at 3C, the batteries can cycle steadily for over 1500 cycles along with ultralow rate of capacity decay (0.044 %). This work opens up a new insight to explore bidirectional catalyst for realizing remarkable performance Li-S batteries.

Limited color expression and inert surface properties are two critical factors that restrict the application of carbon fiber reinforced thermoplastic composites. In this study, we developed an inorganic TiO2 film on carbon fiber surfaces via atomic layer deposition (ALD) as a coloration structure. Subsequently, an organic polyamide (PA) layer was successfully incorporated onto the TiO2-coated carbon fibers through surface modification to enhance interfacial bonding and compatibility between the carbon fiber and PA matrix. The results showed that the PA-modified TiO2 film demonstrates dual functionality, simultaneously achieving vivid structural coloration and enhancing interfacial performance with the PA matrix. The film thickness can be precisely tuned to produce primary colors like blue, green, and yellow by controlling the number of ALD cycles. The intrinsic bond strength (IBS) increased by 23.62% from 40.81 MPa of TiO2 film-coated carbon fiber (ACF) to 50.14 MPa of PA-modified TiO2 film-coated carbon fiber (ASCF). We propose that this method provides an effective approach for developing carbon fibers with multicolor capability and superior interfacial performance.

3D printing polymers and their composites have shown considerable potential in various application fields, yet their limited mechanical properties have hindered widespread use in structural materials. Recently, postprocessing techniques have been proposed as efficient and convenient methods to enhance the mechanical properties of 3D printing structures. This study systematically investigates the effects of thermal annealing and microwave irradiation on the microstructure and mechanical properties of 3D printing carbon fiber reinforced polyamide 12 (CF/PA12). The results clearly demonstrate that thermal annealing significantly outperforms microwave irradiation in improving fiber-matrix interfacial adhesion and crystallization. Specifically, thermal annealing provides necessary time for molecular chain relaxation, effectively releasing internal stresses. Additionally, thermal annealing optimizes the transcrystalline structure at the fiber-matrix interface and the volume fraction of crystalline regions within the matrix. Compared to the pristine samples, the annealed 3D printing specimens exhibited increases of 19.34 % in tensile strength and 27.11 % in flexural strength. This research provides an in-depth insight into enhancing 3D printing CF/PA12 composites through postprocessing techniques and offers a scientific basis for their large-scale application.

High-entropy materials (HEM) are promising electrocatalysts for oxygen evolution reaction (OER) because of their instinctive physicochemical properties and highly tailorable electrochemical properties. However, their synthesis and morphology control remains challenging due to the thermodynamic immiscibility of multimetallic elements under mild conditions. Deep eutectic solvents (DESs) as solvents and temples can affect the morphology and electrochemical performance of OER. Herein, a series of HEM electrocatalysts based on different DESs were synthesized to investigate the effect of DES on the morphology and OER performance of catalysts. The influence of metals on OER performance was further explored. Among them, poly-(ethylene glycol)/thiourea-based HEM catalyst (PEG/TU-NiFeCoMnAl) shows excellent OER performance with an overpotential of only 220 mV and 317 mV at10 mA cm-2 and 100 mA cm-2, respectively. Finally, the influence of different metal active sites on OER performance was analyzed by DFT calculations, and scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, inductively coupled plasma-optical emission spectroscopy (ICP-OES) X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopes (TEM) characterization testing technologies. This work provides a new direction for the construction of advanced high-entropy materials under mild conditions for energy conversion and storage.

The study contributes to the understanding of potassium hexatitanate whisker (PHW) reinforced EPDM composites with superior ablation resistance, which can facilitate the development of high-performance EHSMs for advanced spacecraft. To achieve this, ablative materials with varying PHW content were prepared, and their thermal stability and ablation characteristics were analyzed using thermogravimetric analysis, oxyacetylene ablation test, scanning electron microscope, and other analytical methods. The study unveiled the internal mechanism through which PHW enhances the ablation performance of ablative materials by reducing thermal conductivity and forming carbon fixation centers. Furthermore, micro-morphology analysis revealed that ablative materials containing PHW exhibit a denser surface char layer, thereby enhancing its resistance against erosion. Additionally, the pyrolysis mechanism of EPDM and the formation process of amorphous carbon on TiO2 surface were simulated using molecular dynamics.

Abstract Introduction The safety and efficacy of CRS + HIPEC combined with urinary tract resection and reconstruction are controversial. This study aims to summarize the clinicopathological features and to evaluate the safety and survival prognosis of CRS + HIPEC combined with urinary tract resection and reconstruction. Methods The patients who underwent urinary tract resection and reconstruction as part of CRS surgery were retrospectively selected from our disease-specific database for analysis. The clinicopathological characteristics, treatment-related variables, perioperative adverse events (AEs), and survival outcomes were studied using a descriptive approach and the K-M analysis with log-rank comparison. Results Forty-nine patients were enrolled. Perioperative serious AEs (SAEs) were observed in 11 patients (22.4%), with urinary SAEs occurring in 3 patients (6.1%). Additionally, there were 23 cases (46.8%) involving urinary adverse events (UAEs). The median overall survival (OS) in the entire cohort was 59.2 (95%CI: 42.1–76.4) months. The median OS of the UAE group and No-UAE group were 59.2 months (95%CI not reached), and 50.5 (95%CI: 11.5 to 89.6) months, respectively, with no significant difference (P = 0.475). Furthermore, there were no significant differences in OS based on the grade of UAEs or the number of UAEs (P = 0.562 and P = 0.622, respectively). Conclusion The combination of CRS + HIPEC with urinary tract resection and reconstruction is associated with a high incidence of Grade I-II UAEs, which do not have an impact on OS. The safety profile of this combined technique is acceptable. However, this is a retrospective single-center single-arm analysis, with limitations of generalizability and potential selection bias. The findings need high-level validation.

High-entropy oxides (HEOs) are potential electrocatalysts for overcoming the sluggish kinetics of the oxygen evolution reaction (OER). Conventionally, the thermodynamic barrier of the lattice oxygen mechanism (LOM) is lower than that of the adsorbate evolution mechanism (AEM). However, controlling the transition from the AEM to the LOM remains challenging. Herein, an in situ modulation strategy has been developed to synthesize N-FeCoNiAlMoO x by introducing structural directing agents and electronic modulators. Different instruments were used to identify the nitridation-triggered micromorphologies and phase transformations. X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure spectroscopy (XAFS) reveal the optimized electronic structures after nitrogen doping. N-FeCoNiAlMo x exhibits OER performance with low overpotentials of 240 and 285 mV at 10 and 100 mAcm-2, respectively. pH dependence, free-radical capture experiments, and density functional theory (DFT) calculations confirm that nitrogen doping facilitates the LOM pathway. This work elucidates nitrogen's critical role and the LOM pathway's contribution to efficient OER performance.

Single-layer isophorone diisocyanate (IPDI) are one of the most popular self-healing microcapsules but suffers from low shell strength, poor heat resistance, stability and aging properties. In this paper, IPDI microcapsules were encapsulated into double-layer phenolic (PF)/polyurethane (PU) by a two-step process involving interfacial polymerization and in-situ polymerization. The prepared microcapsule composites were comprehensively characterized for their physical and chemical properties using optical microanalysis, scanning electron microscope, Fourier transform infrared spectroscopy, thermal gravimetric analysis and depth-sensing indentation analysis. Compared with the single-layer PU-IPDI microcapsule counterpart, the mechanical performance, thermal resistance, aging property and environmental stability of double-layer PF/PU-IPDI microcapsules were significantly improved. The epoxy coating was enhanced with the incorporation of 10 wt.% PF/PU-IPDI microcapsules, whose self-healing performance was evaluated by scratch corrosion test. The results demonstrated successful repair of coating scratches, along with the absence of corrosion on the coated steel substrate soaked in a 10 wt.% NaCl solution for 7 days. By comparing the tensile strength of epoxy coating before and after crack formation, it could be found that the self-healing efficiency was 57.9% when loaded with 10 wt.% of PF/PU-IPDI microcapsules in coating. This study highlights that the rational design of double-layer microcapsules integrated into the epoxy coating matrix could provide excellent anti-corrosion and self-healing properties.

Although 3D printing technology has been widely applied in fabrication of polymer composite, yet, it still exhibits low mechanical performance, restricting its application in structural materials. Herein, a new 3D printing polymer composite composed of carbon fiber and polyamide12 (PA12) is fabricated and subsequently treated by microwave treatment. It is found that the tensile strength and modulus of 3D printing CF/PA12 composite with microwave treatment are improved by 23.8% and 10.2% compared with the original specimen, respectively. Moreover, a new mechanism of mechanical reinforcement is investigated and proposed by nanoindentation and 3D X-ray computed tomography. The work does not only confirm formation of 3D printing CF/PA12 composite with good mechanical properties, but also proposes a new mechanism of microwave treatment effect on 3D printing polymer composite based on carbon fiber. Highlights A new 3D printing CF/PA12 composite based on microwave treatment is developed. The 3D printing composite exhibits good mechanical properties. A new mechanism of mechanical reinforcement is proposed.

Development of efficient catalysts for steam reforming of biomass tar is crucial for the widespread application of biomass gasification. In this work, a novel biochar nano-catalyst (BN) is conveniently prepared via one-step catalytic pyrolysis, using K and Fe to adjust the surface structure of the biochar, thereby enhancing the activity for toluene reforming. Fe-K/BN is tested in a fixed-bed reactor for steam reforming of toluene, a model compound of biomass tar, achieving a 100% toluene conversion rate at 650 degrees C. Fe-K/BN is activated in situ with steam to increase their specific surface area and enhance the O-containing functional groups on the surface, improving toluene adsorption and reforming. Finally, the stability of Fe-K/BN is tested in the simulated syngas, maintaining a 100% toluene conversion rate during a 26-h continuous catalytic reforming experiment. This work provides a promising strategy for the design of an active and stable catalyst for toluene reforming, which has potential for application of tar steam reforming during biomass gasification.

We aimed to evaluate the safety and efficacy of hyperthermic intraoperative thoraco-abdominal chemotherapy (HITAC) and cytoreductive surgery (CRS) for peritoneal carcinomatosis (PC) patients who underwent diaphragm resection. PC patients who underwent CRS with diaphragm resection were selected from a prospectively established database and were divided into hyperthermic intraperitoneal chemotherapy (HIPEC) and HITAC groups. The clinicopathological characteristics, treatment-related variables, perioperative adverse events (AEs), and survival outcomes were compared between the two groups. Of 1168 CRS + HIPEC/HITACs, 102 patients were enrolled—61 HITAC patients and 41 HIPEC patients. In the HITAC and HIPEC groups, the incidence of grade III–V AEs was 29.5