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Carbon fibre-reinforced ultra-high temperature ceramics (UHTCs) are considered a class of promising materials for several applications, the most appealing ones being in the aerospace sector. Reinforcement is necessary to overcome the brittleness and low thermal shock resistance of ceramics and is often provided through the addition of carbon fibres or other carbon-based phases, such as nanotubes, graphene, and graphite. The present work is focused on the toughening of UHTCs through incorporation of 30−50 vol% thin, ordered graphite layers from conventional filter paper followed by hot pressing sintering. Cellulose filter paper was selected because it undergoes thermolysis with no melting stage forming a strong carbonaceous residue that can be used as toughener. Microstructure and mechanical properties of toughened composites were compared to those of other materials reinforced with short carbon fibres and the effect of different distribution of graphite was studied. Addition of graphite allowed toughness to be increased from 3−4 MPa·m1/2 (for un-reinforced materials) to 5.1−5.5 MPa·m1/2, similar to results obtained with short fibre reinforcement. The high-temperature properties, such as strength and toughness as well as oxidation resistance at 1500 ℃, were also examined.

Traditionally, cellulose nanofiber (CNF) production has primarily relied on virgin cellulose sources. Yet, the shift to using paper mill sludge (PMS) as a source for CNF underscores the significance of reusing and recycling industrial byproducts. PMS contains significant amounts of cellulose that can be extracted as a raw material. The purpose of present study is to provide a sustainable approach to PMS utilization as a paper coating additive in the cellulose nanofibrils (CNFPMS) form via simply scalable wire-wound rod coating method. The effect of CNFPMS additive amounts at two coating layers on microstructure and surface properties of coatings such as porosity, air permeability surface roughness and optical properties such as brightness, gloss and CIE L*a*b* is studied, which they can also provide insight for the eventual print performance. Results indicated that the obtained CNFPMS in paper coating shows 52% decrease in porosity, presenting significant improvement in the coating microstructure. The marginal increase in permeability coefficient and surface roughness, 54% and 10%, respectively, suggests improving color reproduction and preventing color density losses. Optical analysis showed slight decrease in brightness and gloss, as was expected. Notably, the lightness was improved, which also indicates increasing color gamut volume in printing applications. As a result, the current work offers a sustainable approach to manage PMS for use in paper coatings as a high-value-added material. [ABSTRACT FROM AUTHOR]

Paper is a kind of renewable material that exists widely and has important application prospects. However, previous studies have mostly focused on the macromechanical properties of paper but lack micro theory based on paper fiber networks. We present a comprehensive experimental and computational study on the mechanical properties of fibers and fiber networks under the influence of microstructure. A beam-spring model was established based on a beam-fiber network to simulate the behavior of fiber networks. Simulations were performed to demonstrate the influence of fiber microstructural parameters such as fiber bond strength, stiffness, failure strength, size, and network density on mechanical features. Mechanical experiments verified that the fiber bond strength had a greater influence on the paper properties than did the fiber strength. This result is highly consistent with that of the model. All the simulations were validated by experimental measurements. Finally, we provided computational insights into the interfiber bond damage pattern with respect to different fiber microlevels and demonstrated that the proposed beam-spring model can be used to predict the response of fiber networks of paper materials. The above research can be used to optimize the formulation, process, and treatment of paper to meet specific application needs. [ABSTRACT FROM AUTHOR]

At present, the friendly recycling of paper industry effluent sludge has gained great prominence due to the ecological and economic benefits. The aim of this work is to evaluate the influence of the incorporation of paper industry effluent sludge into a red wall tile formulation (BIII group), replacing natural limestone material by up to 10 wt.%. For this purpose, five red wall tile formulations were developed by the dry process, pressed at 47 MPa, and fired at 1170 ºC by using a fast-firing cycle. The wall tile formulations were characterized in terms of chemical analysis, thermal analysis (DTA-TG), and dilatometric analysis. The influence of paper industry effluent sludge on the technical properties (apparent density, water absorption, and flexural strength) and sintered microstructure was investigated. The results showed that red wall tiles containing up to 10 wt.% of paper industry effluent sludge have very good usable final properties, indicating their suitability for the wall tile industrial production (BIII group - ABNT NBR ISO 13006). Such results emphasize the feasibility of ecological and economic recycling of paper industry effluent sludge for the production of red wall tiles.

The microstructure of fibrous paper plays an important role in its property investigation. In this study, an approach is proposed to extrapolate a 2D image into a virtual 3D microstructure. Five types of handsheets made of different pulps were prepared. Then, a hybrid function of two-point correlation and lineal-path function (S2&L2) and co-occurrence correlation functions (CCFs) was used in the simulated annealing reconstruction method. Thus, microstructures of two-phase fiber-pore handsheets were reconstructed using 2D scanning electron microscopy images. Finally, penetration simulations and calculations of the absolute permeability of handsheets were conducted. The statistical values of two-point correlation function (S2) and lineal-path function (L2) extracted from the reconstructed images were used to characterize the reconstruction accuracy, and the comparisons of reconstruction accuracy and time were made. The study results showed that the 3D microstructures of fibrous handsheets could be reconstructed effectively by S2&L2 and CCFs, identifying with the targets. The accuracies were around 10−5, and the reconstruction times by CCFs were shortened by 30–60% compared with S2&L2. Moreover, the visual permeability simulation results could reflect the structural difference of handsheets, according to the calculated absolute permeability. These findings provide a guidance for 3D reconstruction of natural fiber paper.

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste. [ABSTRACT FROM AUTHOR]

In this work, stacked SiC fibers paper‐reinforced SiC ceramic matrix composites (SiCnf/SiC CMCs) were prepared by nanoimpregnation and transient eutectic (NITE) process using ultra‐long single‐crystal SiC nanofibers. The effect of the SiCnf surface modification via boron nitride (BN) interphase deposition as well as the sintering additive (Al2O3–Y2O3) content on the density, microstructure, and mechanical properties of SiCnf/SiC CMCs has been investigated systematically. The results revealed that the laminated SiCnf/SiC CMCs feature a significant saw‐tooth‐like curve on the load–displacement test, which indicates that the obtained laminated structure with the weak interlayer binding owning to the BN coating treatment possesses significant toughening to the SiC ceramics. Specifically, the SiCnf/SiC CMCs with the sintering additive content of 12 wt% revealed a fracture toughness of over 10 MPa m1/2 after 60 min of BN interface deposition, which is 104.31% higher than that of the composites prepared without BN coating. [ABSTRACT FROM AUTHOR]

This paper describes the fabrication and characterization of porous SiC ceramics derived from highly-filled preceramic papers. The SiC ceramics were obtained by spark plasma sintering of stacked preceramic papers at temperatures of 2100 and 2200 °C under pressures of 5–60 MPa for 10 min. The microstructure and phase composition were analyzed by scanning electron microscopy and X-ray diffraction, respectively. Gas permeation tests were performed using hydrogen permeation cell at room temperature. It is revealed that the porosity of sintered SiC can be varied from 9 to 45 % depending on the sintering parameters. The shrinkage of the materials during spark plasma sintering occurs in four stages. The linear shrinkage value of the material increases from 7 to 47 % at 2100 °C and from 20 to 50 % for the samples sintered at 2100 and 2200 °C, respectively. Correlation dependencies between porosity and mechanical properties of the fabricated SiC were established. The obtained porous SiC ceramics exhibit high bending strength of 165 MPa and gas permeation flux of 78 molH 2 /m2/s at the porosity of 36 % that make it suitable for ceramic-based membranes. [ABSTRACT FROM AUTHOR]

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste.

Polylactic acid (PLA) is chosen as a coating material on industrial Kraft paper substrates to impart a barrier against air, grease, and water. This is an excellent initiative to replace the existing non-biodegradable and petroleum-based coating materials used in many industrial products such as packaging and coated abrasives. In this study, the effect of the crystallinity of PLA on its barrier properties is evaluated. Initially, amorphous and semi-crystalline PLA (sc-PLA) are compared for properties such as coating weight, gloss, heat seal strength, air resistance, grease resistance, contact angle, water resistance, and water vapor transmission rate (WVTR). Sc-PLA is observed to show better barrier properties than its amorphous counterpart. To understand if the barrier properties imparted by a biodegradable coating material on Kraft paper will improve with an increase in crystallinity, sc-PLA is compared to a more crystalline biodegradable polymer, polycaprolactone (PCL). The results indicate that PCL shows compromised results with respect to sc-PLA as a barrier coating material. The theory behind this effect is discussed, and the two bio-based polymers, namely, PLA and PCL, are also comparatively evaluated against the conventionally used synthetic barrier coating materials, acrylic, and varnish, on identical paper substrates under identical process conditions. SEM and DSC analyses on amorphous PLA, sc-PLA, and PCL coatings are also conducted to decipher the microstructural traits of these macromolecules. Sc-PLA serves as an ideal barrier coating material on Kraft paper, and it possesses better hydrophobic properties than untreated, PCL-treated, acrylic-treated, or varnish-treated Kraft paper substrates. [ABSTRACT FROM AUTHOR]

In this work, we report a unique and facile approach to the manufacture of fluorine-free superamphiphobic paper. Based on the principle that Fe3O4 nanoparticles (NPs) arranged along the direction of a magnetic field, the mixture of Fe3O4 NPs and polydimethylsiloxane (PDMS) was coated on kraft paper through self-assembly and thermal-curing at a high temperature in a magnetic field, fabricating a mushroom-like microstructure on the paper. At an Fe3O4 NPs content of 75%, the radius of the mushroom-like pillar caps (RCAP) and center-to-center spacing between two pillars (S) obtained the optimal size of 37 ± 18 μm and 237 ± 38 μm, respectively. The oil-contact angle and water-contact angle of the fabricated paper were up to 156° and 160.4°, respectively. It also showed excellent oleophobic stability; the oil-contact angle was still maintained at 141.9° after 1 h. In addition, the contact angles of milk, ethylene glycol and castor oil were all above 150°, and the contact angle of diiodomethane was 134.2°. Moreover, the sample showed great oil resistance with a kit rating value of 12/12 and permeability of 1800+ s. [ABSTRACT FROM AUTHOR]

Multi-walled carbon nanotubes (MWCNTs) are a high-quality interlamination reinforcement material, but the high viscosity of polyetheretherketone (PEEK) prevents good fusion between MWCNTs and PEEK. This study proposes a method to achieve the complete integration of MWCNTs and PEEK through the preparation of a composite film using the vacuum suction filtration (VSF) method and optimizes the process parameters. An orthogonal experiment with three factors (filter paper pore size, ultrasonic dispersion time, and PEEK content) at three levels is designed, and mechanical performance testing and microscopic morphology observation are conducted. The influence of the three factors of filter paper pore size, ultrasonic time, and PEEK content on the elastic modulus and tensile strength of the film is investigated. The results are a filter paper pore size of 0.45 μm, ultrasonic time of 8.3 h, and PEEK content of 336.524 mg. The mechanical performance obtained under the optimal process parameters are an elastic modulus of 2437.5723 MPa and a tensile strength of 46.5196 MPa. This optimal process increases the elastic modulus by 12.3152% while maintaining a high tensile strength. [ABSTRACT FROM AUTHOR]

The paper proposes a new approach to gradient porous composites based on the Ti3Al(Si)C2 MAX phase. This approach is based on the production of preceramic paper with the different content of the powder filler based on MAX phases and their spark plasma sintering. The analysis of the microstructure and phase composition is conducted for these composites. It is shown that the obtained composites have a clear interface between layers with different porosity. It is found that the content of organic components in preceramic paper affects the phase composition of the fabricated composites. The MAX phase content in dense and porous layers is 86 and 56 vol.%, respectively. Microhardness measurements performed in the composite cross-section show the hardness of 600 to 800 HV, depending on the layer porosity and phase composition. [ABSTRACT FROM AUTHOR]

This paper identifies physical properties of an interesterified palm‐based fat (EIEPO) that predict oil binding capacity (OBC). A 100% EIEPO sample, 50% EIEPO sample diluted with 50% soybean oil (SBO), and a 20% EIEPO sample diluted with 80% SBO were used to test how saturation level impacts OBC. All samples were crystallized using either a fast (6.4°C/min) or slow (0.1°C/min) cooling rate as well as with or without the application of high‐intensity ultrasound (HIU; 20 kHz) to generate a wide range of physical properties. Immediately after crystallization, the sample's physical properties, including crystal microstructure, solid fat content (SFC), viscoelasticity (G′, G″, and δ), melting behavior, hardness, and OBC (centrifuge method) were quantified. The samples were then stored for 48 h at 22 and 5°C and the aforementioned physical properties were measured again, with one additional measurement for the samples stored at 5°C—OBC using a filter paper method (OBCp). The results indicate that OBC can be optimized in a palm‐based fat by modifying the physical properties which was achieved via the processing conditions. Both measurements of OBC were significantly correlated with SFC, hardness, δ, and enthalpy. A model was developed to predict a sample's OBCc using the following dominant variables—SFC, hardness, peak temperature, enthalpy, and the number of crystals. These results suggest that OBC can be predicted using a sample's SFC, hardness, peak temperature, enthalpy, and number of crystals and that SFC, hardness, and enthalpy are main drivers of OBC. [ABSTRACT FROM AUTHOR]

This study evaluates the potential use of discarded plasterboard paper as fibers from buildings to reinforce concrete. Various concentrations of wastepaper fibers (0.5%, 1%, 1.5%, 2%, and 2.5% by weight of the binder) were investigated in this research. To mitigate the water absorption effect of the paper fibers, metakaolin was employed as a partial cement replacement. The results demonstrate that the inclusion of the wastepaper fiber enhances the mechanical and durability performance of the concrete. The optimal fiber proportion was identified as 1%, leading to a 29% increase in the compressive strength, a 38% increase in the splitting tensile strength, a 12% decrease in the water absorption, and a 23% decrease in the drying shrinkage with respect to the concrete containing 20% metakaolin. However, exceeding this optimal fiber content results in decreased mechanical and durability properties due to the fiber agglomeration and non-uniform fiber distribution within the concrete matrix. Based on the microstructural analysis, the improved performance of the concrete is ascribed to decreased porosity, more refined pore structure, and reduced propagation of microcracks within the concrete matrix in the presence of wastepaper fiber. According to the results, concrete containing 20% metakaolin and 1% wastepaper fiber exhibits durability and mechanical properties comparable to those of the traditional concrete. This finding highlights the significant promise of reducing dependency on conventional cement and incorporating suitable recycled materials, such as discarded plasterboard, and secondary by-products like metakaolin. Such a strategy encourages the preservation of resources, reduction in carbon dioxide emissions, and a decrease in the ecological footprint resulting from concrete production. [ABSTRACT FROM AUTHOR]

In this study, continuous carbon reinforced C f /(Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C–SiC high entropy ceramic matrix composites were additively manufactured through paper laminating (PL), direct slurry writing (DSW), and precursor infiltration and pyrolysis (PIP). (Ti 0.2 Zr 0.2 Hf 0.2 Nb 0.2 Ta 0.2)C high entropy ceramic (HEC) powders were synthesized by pressureless sintering and ball milling. A certain proportion of HEC powder, SiC powder, water, binder, and dispersant were mixed to prepare the HEC-SiC slurry. Meanwhile, BN coating was prepared on the 2D fiber cloth surface by the boric acid-urea method and then the cloth was cut into required shape. Additive manufacturing were conducted subsequently. Firstly, one piece of the as-treated carbon fiber cloth was auto-placed on the workbench by paper laminating (PL). Then, the HEC-SiC slurry was extruded onto the surface of the cloth by direct slurry writing (DSW). PL and DSW process were repeated, and a C f /HEC-SiC preform was obtained after 3 cycles. At last, the preform was densified by precursor infiltration and pyrolysis (PIP) and the final C f /HEC-SiC composite was prepared. The open porosity of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 7.7, 10.6, and 11.3%, respectively. And the density of the C f /HEC-SiC composites, with the HEC volume fractions of 15, 30 and 45%, were 2.9, 2.7 and 2.3 g/cm3, respectively. The mechanical properties of the C f /HEC-SiC composites increased firstly and then decreased with the HEC content increase, reaching the maximum value when the HEC volume fraction was 30%. The mechanical properties of the C f /HEC-SiC composites containing 45, 30 and 15% HEC were as follows: flexural strength (180.4 ± 14 MPa, 183.7 ± 4 MPa, and 173.9 ± 4 MPa), fracture toughness (11.9 ± 0.17 MPa m1/2, 14.6 ± 2.89 MPa m1/2, and 11.3 ± 1.88 MPa m1/2), and tensile strength (71.5 ± 4.9 MPa, 98.4 ± 12.2 MPa, and 73.4 ± 8.5 MPa). From this study, the additive manufacturing of continuous carbon fiber reinforced high entropy ceramic matrix composites was achieved, opening a new insight into the manufacturing of ceramic matrix composites. [ABSTRACT FROM AUTHOR]

In this work high strength and tough metal‐ceramic laminated composites are fabricated by spark plasma sintering (SPS) of Ti3Al(Si)C2 MAX‐phase filled preceramic papers (TAC) and ductile Nb foils. The sintering is carried out at 1250 °C and 50 MPa for 5–20 min. Various stacking techniques are used to obtain Nb/TAC laminated composites with different architectures. SPS results in the formation of reaction layer (RL) with a complex composition, which changes the thickness insignificantly with increasing sintering time. The possible formation mechanism of RL is discussed. The bending strength of Nb/TAC composites is decreased from 410 to 350 MPa when lowering the thickness of ceramic layer. The maximum fracture toughness of 10.2 MPa·m1/2 is achieved for the composite with similar individual layers thickness. The toughening is explained by complex fracture mechanisms associated with deflection and branching of cracks at interfaces, delamination, plastic deformation of Nb layers, multiple cracking and crack deflection in ceramic TAC layers. [ABSTRACT FROM AUTHOR]

The history of antimony modification of Al–Si casting alloys is reviewed, together with the important technical and commercial reasons why antimony is no longer used as a modifier. [ABSTRACT FROM AUTHOR]

This paper describes the fabrication and characterization of novel preceramic paper-derived functionally graded materials (FGMs) based on Ti 3 (Si,Al)C 2 MAX phase. The FGMs with different architecture were fabricated via spark plasma sintering of stacked preceramic papers at 1250 °C for 5 min. Microstructure, phase composition and elemental distribution were analyzed by scanning electron microscopy, X-ray diffraction and energy-dispersive X-ray spectroscopy, respectively. Oxidation tests were performed in air at 1300 °C for 5 h. FGMs containing Al- and Si-enriched MAX-phase layers were formed. The fabricated materials exhibit high flexural strength (over 600 MPa), which are dependent on microstructure and composition of individual layers as well as the architecture of composites. It was found that texturing of MAX phase grains during SPS results in anisotropic hardness of the composite. The difference in the composition of the individual layers also provides a hardness gradient in the composite. It was shown that the formation of the outer layer from the Al-enriched Ti 3 Al(Si)C 2 MAX phase increases the corrosion resistance of Ti 3 SiC 2 -based composites. The high corrosion resistance of FGMs is due to the growth of a continuous and dense Al 2 O 3 oxide layer. [ABSTRACT FROM AUTHOR]

Cellulose‐based paper samples were surface‐modified by a polymeric single‐source precursor prepared from perhydropolysilazane (PHPS) and iron(III)acetylacetonate (Fe(acac)3) and ammonolyzed at 500°C, 700°C, 900°C, and 1000°C, leading to C/SiFe(N,C)O‐based ceramic papers with in situ‐generated hierarchical micro/nano‐morphology. As reference, cellulose‐free samples were prepared under the same conditions. Upon thermal treatment, the microstructure evolutions of the resulting ceramic paper and the reference sample were comparatively investigated. Scanning electron microscopy (SEM) showed that for all temperatures, the ceramic papers exhibit the same morphology as the template, however, with noticeable shrinkage and curling, particularly evident at higher temperatures. X‐ray diffraction (XRD) measurements of the reference samples and the ceramic papers showed a similar crystallization behavior and phase evolution in both materials. In the ceramic paper, the crystallization process seems to occur at a later time. The results provide a comprehensive understanding of the investigated C/SiFe(N,C)O‐based ceramic system. It was shown that use of the cellulose‐based paper template has the benefit of retaining the microstructure and furthermore, apart from transforming the cellulose fibers into turbostratic carbon, does not change the phase evolution during the polymer‐to‐ceramic transformation, allowing at the same time the manufacturing of novel morphologically complex parts by a convenient one‐pot synthesis approach. [ABSTRACT FROM AUTHOR]

Biodegradable paper mulch has the advantages of being easily degradable and environmentally benign, but its own performance and adaptability to harsh environments have not been tested. This paper uses scanning electron microscopy and three-dimensional morphometry to microscopically characterize biodegradable paper mulch and white plastic mulch. To analyze and compare their mechanical and hydrophobic properties, and weather resistance, the two mulches were measured through tensile tear load and static contact angle. A comparative analysis of the effect of mulching in the dry crop area of the Hexi Corridor was conducted by comparing the growth index, farm water heat, soil oxygen content, and yield using maize and flax. The test results show that biodegradable paper mulch films were slightly inferior to traditional white mulch films in terms of mechanical and hydrophobic properties, with inadequate insulation and moisture retention, but better in terms of aging resistance, soil oxygen content, and crop insulation and water storage capacity in the middle and growth stages. White mulch film had a better yield enhancement effect on maize, while with biodegradable paper mulch film, this was more significant with flax. [ABSTRACT FROM AUTHOR]

Moisture sorption and diffusion processes of plant fiber materials have a significant impact on their properties and product quality in healthcare, food production, cigarette processing, textile field, and papermaking industry. The infiltration process affects the rate of water sorption and processing of flavoring liquids, and exploring its mechanisms can optimize the production process. Here, multi-scale imaging approach was employed to identify the heterogeneous structure of plant leaves and the impact of multilevel fiber structure and pore channels on water adsorption. The dissipative changes and mechanisms of water adsorption, osmotic diffusion, and hygroscopic swelling in plant leaves were illustrated. Furthermore, the effects of temperature and water activity on water diffusion under different environmental conditions are determined through a comparison of adsorption equilibrium and diffusion electrochemical impedance analysis (EIS), with a focus on the water-blocking effect of the waxy layer interface. This work investigated the correlation between the impedance change in water transport and the natural layered water-blocking polymer film structure and multi-level pore structure. This study sheds new light on biological multi-scale fiber materials and these findings are important reference value for manufacturing processes to improve the moisturizing properties of functional plant fibers in the field of food preservation. [ABSTRACT FROM AUTHOR]

The drainage properties of a gas diffusion layer (GDL) are essential factors in the performance of proton exchange membrane fuel cells. The GDL consisting of a three-dimensional (3D) carbon paper microstructure was developed and meshed with pore-scale reconstruction models in this paper. Localized binder and polytetrafluoroethylene (PTFE) structures were added to the carbon paper microstructure through 3D morphological imaging processing. The monitoring data of 1000 planes were multi-peaky fitted as a function of gas permeability and height to amend the macroscopic porous medium model. We analyzed drainage properties under different contact angles (θ) for the carbon paper with binder and PTFE. We described the mutual intrusion of moisture and air in GDL under different pressure differences. The results show that the pore-scale reconstruction model has the advantages of describing the flow in GDL accurately and with details, detecting low-flow resistance channels that spontaneously formed in GDL, and describing the variation of permeability as a function of location. In a hydrophobic environment, the liquid film connected to a GDL is challenging to split spontaneously. At the same time, the splitting motion of discrete droplets is more prominent than that of the liquid film. The pressure that enables complete water intrusion into the GDL is between 1 and 10 MPa. [ABSTRACT FROM AUTHOR]