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Sport plays a crucial role in human society, fostering physical health, collaboration, and the spirit of rivalry. The importance of sports in promoting a sense of well-being, self-control, and cognitive sharpness should be considered. The efficacy of sports and athletic performance often relies on the caliber of clothing used. Traditional sportswear encounters many issues, including but not limited to restricted breathability, inefficient moisture management, and insufficient ultraviolet (UV) protection. To examine these concerns, the present study investigates the Intelligent Sportswear Design (ISWD), an innovative advancement rooted in conjugated nanomaterials. The field of ISWD covers the development of sports apparel and footwear specifically intended to boost performance and provide optimal comfort. Coatings of graphene, silver nanoparticles, and environmentally friendly green nanomaterials are employed in these multipurpose PES fabrics. This research looks at how we might better protect athletes from the sun by developing fabrics with UV-blocking qualities. Results show increased moisture-wicking efficiency, better UV-radiation protection, and enhanced electrical conductivity. The study found that fabric moisture management could be improved by 25%, UV-blocking performance could be increased by 30%, fabric conductivity could be increased by 15%, and heat retention could be decreased by 20%. The experimental results show that the proposed ISWD exhibits notable performance in several necessary measures, including moisture-wicking effectiveness (23.22%), UV-blocking performance (34.22%), fabric conductivity (20.88%), heat retention reduction (26.94%), and UV radiation shielding (35.68%).

We propose a predictive model for various sensory textures utilizing machine learning techniques based on the largest rheology and panel-tested sensory texture database ever assembled. In addition to the conventional rheological parameters typically measured in the cosmetics field, rheological parameters obtained from the large amplitude oscillatory shear (LAOS) sequence of physical processes (SPPs) and extensional rheology analyses are employed as feature variables for the predictive model. These feature variables are chosen to mimic real flow conditions during the usage of cosmetics, such as rubbing and tapping, as they are expected to contain more information related to sensory textures. It has been demonstrated that our prediction model, based on the random forest regression algorithm, can effectively predict five sensory textures: spreadability, thickness, softness, adhesiveness, and stickiness. We investigated the rheological characteristics crucial for determining each sensory texture through permutation and feature importance analyses. The important analysis highlighted the close correlation between rheological parameters from LAOS–SPP, extensional analyses, and sensory textures. By using this correlation, we interpret the perception of each sensory texture in the context of rheology.

The acoustic performance of metal hollow sphere (MHS) A356 aluminum matrix composites has a significant impact on their application, making it worthy of in-depth investigation. To investigate the acoustic performance and mechanism of MHS A356 aluminum matrix composites, in this study MHS A356 aluminum matrix composites with different structural parameters were fabricated using a casting method. The density of the MHS A356 aluminum matrix composites was measured using the direct measurement method, and the acoustic performance of the composites was measured using the impedance tube. The research results indicated that the average sound absorption coefficient of MHS A356 aluminum matrix composites increased with the decrease in sintering temperature and diameter of MHSs, and the increase in volume fraction of MHSs. When the sintering temperature of the MHS was at 1,100°C, with the volume fraction being 48.50% and the diameter being 1.88 mm, the average sound absorption coefficient of the MHS A356 aluminum matrix composites reached the optimal level, which was 0.23. Conversely, the sound transmission loss of MHS A356 aluminum matrix composites decreased with the increase in sintering temperature, volume fraction, and diameter of MHSs. When the sintering temperature of the MHS stood at 1,100°C, with the volume fraction being 40% and the diameter being 2.88 mm, the average sound transmission loss of the MHS A356 aluminum matrix composites attained the maximum value, which was 24.6 dB.

This experimental study focuses on exploiting laser Doppler velocimetry (LDV), a non-intrusive technique, for rheological characterization based on analyzing flows of Carbopol solutions at two distinct concentrations and two different temperatures within a pipe. The velocity profiles obtained using LDV and the pressure drops associated with each flow rate were exploited to establish the behavioral law of aqueous Carbopol solutions. Two approaches were used: the first was an analytical velocity model to fit the experimental profile, and the second used the first derivative of the experimental velocity profile and the pressure drops to reconstruct the flow curve. In addition, a third reference characterization was carried out using a rotary rheometer equipped with a vane geometry. This study’s three rheological characterization methods showed excellent agreement concerning the Herschel–Bulkley model. Finally, all the laws resulting from these three methods were validated using an empirical law relating to Darcy’s coefficient of friction.

As one of the main problems in the processing of carbon fiber reinforced polymer (CFRP), tool wear affects the quality and efficiency of hole making. As a new CFRP hole making process, the suction-type internal chip removal method can effectively slow down the tool wear rate. In order to further clarify the reasons for this method to slow down the tool wear, this study investigates the wear mechanism of the internal chip removal tool. The main contents include: first, the experimental parameters such as drilling axial force, drilling temperature, and tool wear are obtained through the experimental method, and the drawing of the drilling temperature change curve of internal chip drilling is completed; second, the polar analysis method is used to study the influence of the drill parameters on the drilling axial force and the tool wear, and the basis for the selection of the structure of the internal chip drill is given; finally, the method of comparative experiments of the internal chip drilling process and the non-internal chip drilling process is used to conclude that the use of the internal chip drilling process can effectively slow down the tool wear rate. Finally, the method of comparing the internal chip removal and non-internal chip removal processes is used to conclude that the use of internal chip removal processing method can effectively reduce the axial force, drilling temperature, and slow down the tool wear.

Deep and thick weathered granite crusts widely distributed in Xiangdong area, Hunan Province, due to their special structure, often induce geological disasters such as landslides under the conditions of excavation or atmospheric precipitation. In this article, using the direct shear test, X-ray diffraction test and scanning electron microscope test, the mechanical properties and the response mechanism of the microstructure of the granite residual soil in eastern Hunan area under different states were studied, and the structural damage mechanism of the granite residual soil was analysed. Based on the comprehensive structural potential, the theory characterizes its structure. The results show that the granite residual soil is mainly composed of minerals such as quartz, mica, kaolinite and feldspar, and it also contains a small amount of chlorite and calcite. The damage is mainly reflected in the attenuation of cohesion, while the change of the internal friction angle is small. The microscopic manifestation is the failure of the bridging structure between the aggregates, and the inter-granular pores are interconnected. The difference and shear strength response reflect the susceptibility to disturbance of granite residual soil and reflect that the structural strength has been damaged under the disturbance of human factors.

The rheological properties and seepage laws of fractured rock masses have a highly significant impact on the long-term stability of engineering rock masses. To study the rheological properties and seepage laws, rheological experiments under different loading paths were designed and conducted on sandstone samples with pre-fabricated single fractures. The results indicated that (1) as the axial stress or pore pressure increases, or the confining pressure decreases, the creep strain (both axial and radial directions) during the creep tests increases, and their stain rate decreases; (2) compared to the pore pressure, the axial stress and confining pressure have a more significant influence on the flow rate during the creep process. As the axial stress increases or the confining pressure decreases, the flow rate shows an increasing trend; (3) the higher connectivity results in higher final flow in an exponential function, indicating that the connectivity ratios can well reflect the permeability of the fractures; (4) the changes in the stress field may lead to the transition of the surrounding rock from a stable state to an unstable state, i.e., the occurrence of creep failure, or water inrush. Therefore, when the state of the surrounding rock changes, strengthened monitoring and proper preventive measures should be implemented.

In order to determine the influence of the ondulations in fabrics on the damping properties of fiber-reinforced plastics, the structural dynamic properties of fabric- and unidirectionally reinforced plastics are investigated. The free decay behavior of flat beam-like specimens is investigated under fixed-free boundary conditions. As the material damping is consistently higher in fabric-reinforced specimens compared to unidirectionally reinforced ones, a contribution of an additionally acting mesomechanic kinematic in fabric weaves is implied. Based on a degree of ondulation, it is possible to classify the enhancement of the material damping and determine the corresponding energy dissipation. The study provides valuable quantitative relations of the additional damping effect due to the mesomechanic kinematic. Compared to the unidirectionally reinforced material, plain weave enhances the material damping by 37…52% at O˜PL=0.0133{\tilde{O}}_{{\rm{PL}}}=0.0133, whereas twill weave 2/2 enhances it by 31…40% at O˜T2=0.0098{\tilde{O}}_{{\rm{T2}}}=0.0098. The consideration of the findings contributes to a deeper understanding of the visco-elastic dynamic behavior of fabric-reinforced plastics and allows further applications in research, development, and industry.

In this work, the AA6063 Al alloy was processed by cooling at four different conditions. The impact of the type of cooling method on the corrosion behavior of the produced alloys after 1 and 24 h in 3.5% NaCl solutions was carried out. Various electrochemical measurements, such as cyclic potentiodynamic polarization (CPP), chronoamperometric, and electrochemical impedance spectroscopy (EIS) measurements, were employed. The CPP data revealed that the intensity of corrosion of the alloys is highly influenced by the cooling method. The change in the chronoamperometric current at −650 mV (Ag/AgCl) over time indicates the possibility of pitting corrosion, particularly after 24 h, where the recorded currents showed a continuous increase over time. The scanning electron microscopy images taken for the surfaces of the alloys after corrosion confirmed that the lowest deterioration occurring on the surface was for the AA6063 alloy that was quenched in water. The EIS plots also demonstrated that AA6063 alloy exhibits different corrosion resistances when different cooling methods are applied. All measurements indicated that the corrosion resistance increases in the following order: the quenched alloy in water > the air-cooled alloy > the furnace-cooled alloy > the as-received alloy. The exposure for 24 h decreases the corrosion damage of all alloys via the formation and thickening of a top layer of corrosion products on its surface over time.

In the development of carbon nanotube (CNT)-reinforced cement-based matrices, one of the fundamental issues that investigators are confronting is CNT/cement-based matrix interfacial bonding, which determines the load transfer capability from the matrix to the CNT. In the present work, the stress transfer properties of multi-walled carbon nanotubes (MWCNTs) and ultralight foamed concrete matrices were studied using microscopic Raman spectrometry analysis. Two types of CNTs, such as MWCNT and MWCNT-COOH, were considered, wherein MWCNT-COOH was covered with fundamental COOH groups. The results show that the compressive and flexural strengths were 75 and 236% better for ultralight foamed concrete with a dry density of 200 kg/m3 with 0.4 wt% MWCNT-COOH addition, respectively. This indicates that the fundamental COOH groups of the MWCNT play an important role in determining the interfacial bonding characteristics between the MWCNT and the ultralight foamed concrete matrix. Therefore, the attachment of COOH groups with a reasonable concentration to the MWCNT surface may be an effective way to significantly improve the load transfer between the MWCNT and the ultralight foamed concrete matrix, leading to increased compressive and flexural strength values of composites.

As industries rely more and more on magnetohydrodynamic (MHD) systems for different uses in power, production, and management of the environment, it becomes essential to optimize these operations. The study seeks to improve the effectiveness and productivity of cooling structures, chemical reaction reactors, and contaminant control methods by investigating these intricate interconnections. Because of this, the work scrutinizes the endothermic/exothermic (EN/EX) chemical processes, convective boundary conditions, and pollutant concentration impacts on MHD nanofluid circulation around a rotating sphere. The governing equations based on the above assumptions are reduced into a system of ordinary differential equations and solved numerically with Runge–Kutta Fehlberg’s fourth- and fifth- order schemes. The obtained numerical outcomes from the numerical scheme are presented with the aid of graphs, and the results show that the rate of mass transfer decreases with an increase in the external pollutant local source and solid volume percentage. For changes in the values of the activation energy parameter and solid fraction, the rate of thermal dispersion drops for the EN case and upsurges for the EX case. The concentration profile shows increment with the addition of the external pollutant source variation parameter and local pollutant external source parameter. The outcomes of the present work can be helpful in cooling equipment, developing advanced methods for controlling pollution, environmental management, MHD generators, and various industrial contexts.

Calcareous sand is easily broken under external force, which brings great difficulties to island reef engineering. Based on the particle flow program, a discrete element model that can reproduce the results of laboratory tests is established, the large principal stress method is introduced to identify the particle force chain, and the bond strength between particles is increased to obtain an unbreakable model with the same initial conditions, and different confining pressures are compared and analyzed. The evolution law of the force chain of the following two models establishes a macro-meso cross-scale analysis in the deformation process of calcareous sand, explores the internal mechanism of the crushing of calcareous sand particles. The results show that particle breakage plays an important role in the evolution of the force chain. Particle breakage will reduce the probability of the force chain on both sides of the axis, forcing the probability of the axial force chain to rise steadily. The macroscopic deviatoric stress is the external manifestation of the probability of the axial force chain on the meso level. The faster the probability of the force chain in the direction of the potential shear band increases, the more obvious the shear band is.

The study aims to substitute river sand used in ultra-high performance concrete (UHPC) with pond ash (PA), a waste by-product from the Sikka thermal power station in Gujarat, India, at replacement levels ranging from 0 to 20%. Also, 20% of the cement was replaced with ground granulated blast-furnace slag, which is a sustainable, eco-friendly material. As a result, this concrete is both environmentally and economically feasible. Experimental analysis evaluated the workability, compressive strength, split tensile strength, flexural strength, and microstructure of the UHPC mixtures. Incorporating 10% PA as a sand replacement enhanced the compressive strength, reaching 117 MPa at 90 days, as well as the flexural strength of 23 MPa and the split tensile strength of 14 MPa. The strength is positively impacted when 10% of the river sand is replaced with PA, while the strength of UHPC appears to be diminished if PA content is increased beyond 10% replacement of sand. Petrographic microscopy and X-ray diffraction were used to study the microstructure of UHPC made with PA. When PA was used instead of sand, the mortar mass solidified and became denser, resulting in an improved microstructure of the UHPC with fewer surface cracks. With the inclusion of PA, the calcium silica hydrate gel content of the concrete increases, and enhanced performance of UHPC up to a certain amount of replacement has been observed.

To realize the recycling of iron tailings powder (IP) and desulfurization ash (DA) and reduce the high preparation cost of mine filling cementitious materials (MCs), this article adopts sodium carbonate (SC) as an activator to prepare iron tailings powder-desulfurization ash mine filling cementitious materials (IDMC). The effects of IP content, DA content, SC content, and mirabilite content on the mechanical properties and setting time are experimentally investigated. The micromorphology and phase compositions of the hydration products of IDMC are analyzed and characterized by scanning electron microscopy and X-ray diffraction. The results show that the initial setting time of the IDMC is reduced by 0.87 and 21.83% when the mirabilite content is increased from 0 to 1% and 2%, respectively, and the compressive and flexural strengths of the IDMC are increased by 24.01 and 86.25% when the IP content is increased from 0 to 20%, respectively. The IP not only participates in the hydration reaction but also plays an aggregate filling effect, significantly improving the mechanical properties of the IDMC. The pozzolanic effect is gradually enhanced with the increase of the DA content, and the hydration degree of the IDMC increases. The SC as an activator can moderately reduce the shrinkage rate of the IDMC. Based on the multi-index optimization analysis, the optimal mix proportion of the IDMC is obtained, which provides an effective reference for the preparation of the novel MC.

The 2.5D carbon glass hybrid woven composite (CGHWC) is currently being utilized as a protective material for the external cables of solid rockets due to its extensive advantages in terms of structural load-bearing and integrated thermal insulation. This study reveals that 2.5D hybrid woven composites, prepared using T300 and T800, exhibit improved compression and tensile properties, respectively. T300 and T800 carbon fibers are preferred for the preparation of 2.5D CGHWC, with a volume fraction of carbon fibers along the weft yarn ranging from 20 to 60%. As the proportion of carbon fibers increases, the weft tensile and compressive strength of the composite material progressively improve, resulting in a maximum increase of 67% in tensile strength and 52% in compressive strength. The optimal volume fraction of carbon fibers was found to be 40%. The performance retention of low-cost hybrid composite materials was investigated, and it was found that even when the cost of carbon fibers decreased by 87.5%, the mechanical properties could still be maintained at above 85%. This article has expanded the mechanical performance database of hybrid composite materials, providing data support and theoretical foundation for the large-scale engineering application of composite materials.

Many applications, including micro air vehicles, automotive, aerospace, refrigeration, mechanical–electromechanical systems, electronic device cooling, and micro heat exchanger systems, can be used to determine the heat flow in microchannels. Regarding engineering applications, heat flow optimization discusses the role of entropy production minimization. Therefore, this work explores new facets of entropy production in fully developed Carreau fluid heat transport in an inclined microchannel considering exponential space/temperature dependence, radiative heat flux, and Joule heating. The Carreau fluid model’s rheological properties are taken into account. Additionally, the influence of Hall slip velocity and convective boundary conditions is considered. Using appropriate transformation constraints, the governing equations are transformed into a system of ordinary differential equations, which are then numerically solved using the fourth- and fifth-order Runge–Kutta–Fehlberg method. Graphs illustrate a significant discussion of physical parameters on production of entropy, Bejan number, thermal field, and velocity. Our findings established that there is a dual impact of entropy generation for the exponential space/temperature-dependent, radiation parameter, Hall parameter, Weissenberg number, and velocity slip parameter. The Bejan number decreased with the Hall current and the Weissenberg number, and it enhanced with exponential space/temperature dependent. The convection constraint maximizes the entropy at the channel walls. The results are compared with exact solutions, which show excellent agreement.

With the development of urbanization, there is an increasing demand for higher land utilization rates, leading to the emergence of high-rise residential and commercial complexes. Additionally, in coastal areas, the presence of soft soil and low bearing capacity of the foundation necessitate higher foundation bearing capacity. Large-diameter, super-long piles have been widely employed in engineering projects to address these challenges effectively. This study analyzes their vertical bearing characteristics through field load tests and determines vertical load distribution and transfer mechanisms by using Brillouin Optical Time Domain Reflectometry. A numerical computation and analysis method based on PLAXIS 3D was established, examining the effects of parameters such as pile diameter, length, and soil modulus on the vertical bearing characteristics. Results indicate that large-diameter, super-long piles mainly bear loads through side friction, with the tip bearing less load. As load levels increase, axial force increases linearly above 40 m depth and becomes nonlinear below. Frictional resistance is significant below 40 m at 3,700 kN load. Parameter analysis shows that increasing pile length and diameter enhances bearing capacity, suggesting this method to improve pile foundation capacity in engineering.

The aim of this study is to enhance the carbonation resistance of fully recycled aggregate concrete through diverse measures in an effort to enhance solid waste disposal, reduce the consumption of natural aggregates, and broaden the utilization of recycled aggregate concrete. Six sets of fully recycled aggregate concrete specimens were prepared and subjected to rapid carbonation tests. Carbonation depth and compressive strength measurements were taken at different ages (3, 7, 14, and 28 days). Subsequent calculations and analyses were conducted on both parameters for each set of specimens. Results indicate that the incorporation of microspheres and high-toughness polypropylene fibers (HTPP) substantially improves the carbonation resistance of fully recycled aggregate concrete, leading to a 48% reduction in carbonation depth by the 28th day. Furthermore, a relative compressive strength model for fully recycled aggregate concrete post-carbonation was established based on the strength data of each specimen group. This model accurately depicts the growth pattern of compressive strength after carbonation. Additionally, a carbonation depth prediction model was developed through fitting analysis of carbonation depth data, effectively foreseeing the depth of carbonation in fully recycled aggregate concrete. Based on the carbonation depth, the carbonation life of fully recycled aggregate concrete was predicted. The carbonation life of recycled aggregate concrete with added microspheres and HTPP fibers can be increased by up to 278%. Finally, scanning electron microscopy (SEM) was employed to examine the microstructure of fully recycled aggregate concrete, revealing the mechanisms by which various methods enhance its carbonation resistance. The carbonation resistance improvement technology of fully recycled aggregate concrete is selected through this study characteristics such as simplicity, convenience, and cost-effectiveness, which are crucial for the widespread application of recycled aggregate concrete in building structures.

The aim of this study is to investigate the impact of various ambient temperatures on the mechanical properties of full aeolian sand concrete (ASC100). Using ordinary concrete (ASC0) as the control group, we analyzed the effects of different ambient temperatures (−20, −15, −10, −5, 0, and 20°C) on the mechanical properties of both ASC0 and ASC100 through cube compression, splitting tensile, and uniaxial compression tests. The results demonstrate that the compressive strength and splitting tensile strength of concrete cubes increased with decreasing temperature. At −20°C, the compressive strength of ASC100 increased by 30.1% and that of ASC0 increased by 27.31% compared to that at 20°C. Additionally, compared to normal temperatures, the elastic modulus of ASC0 and ASC100 at subzero temperatures increased by 28.2–61.4% and 6.8–65.7%, respectively, while the peak stress increased by 7–35% and 6.8–38%, respectively. The stress–strain curve of ASC100 showed three stages: elastic, elastic-plastic, and yield failure, serving as the reference group. Finally, based on the classical constitutive model, we modified the constitutive parameters by axial compressive strength and temperature, proposing a constitutive model of concrete suitable for different low-temperature environments, which is in good agreement with experimental data.

Composite sandwich structures are widely used in the aerospace field due to their advantages of high strength, lightweight, and fatigue resistance. However, these structures are prone to damage with very-low-energy impacts. In order to improve the impact resistance of aircraft skin structure, a low-velocity impact resistance of sandwich structure specimens was tested by means of drop hammer impact, and the impact damage area was scanned by ultrasonic C-scan, and obtains the impact damage of specimens with different impact energies and different ply sequences. Combined with the Hashin failure criterion, the finite element equivalent model of composite sandwich structure under low-velocity impact was established. The errors between the simulation results and the C-scan results of the test piece were less than 10%, in which the experimental measurements and numerical predictions were in close agreement. Finally, the finite element equivalent model was applied to optimize the application of model sandwich, which was used for fuselage skin of a certain electric aircraft. The total thickness of the laminate structure remains unchanged before and after optimization, but the impact resistance was significantly enhanced. The ±45° lay-up was beneficial for the structure to absorb the impact energy.

This study examines the impact of the recycled brick powder (RBP) replacement rate, especially at elevated temperatures on RBP-ultra-high-performance concrete (UHPC) properties such as the stress–strain curve, Poisson’s ratio, elastic modulus, and axial compressive strength through uniaxial compression experiments. The results show that with the increase of heating temperature, the axial compressive strength of the specimen increases first and then decreases under natural cooling (NC). In contrast, Poisson’s ratio shows opposite values. The peak strain continues to increase, and the initial elastic modulus and peak secant modulus continue to decrease. Compared with NC, the axial compressive strength of the specimens under water cooling has been reduced, the peak strain is generally larger, the initial elastic modulus and the peak secant modulus are smaller, and the incorporation of RBP also has a certain effect on the mechanical properties. Through regression analysis, an equation is established to calculate the axial compressive strength of RBP-UHPC with temperature, accounting for variables such as temperature, RBP replacement rate, and cooling method. Furthermore, based on the results of axial compression experiments, a constitutive equation for axial compression in RBP-UHPC after exposure to high temperatures is proposed. Overall, the theoretical curve closely aligns with the experimental curve, verifying its accuracy.

To evaluate the mechanical property of concrete materials rapidly, a fast prediction model of the concrete equivalent modulus is proposed based on the random aggregate model and scaled boundary finite element method (SBFEM). First, a random aggregate model of meso-concrete is employed to construct the representative volume element (RVE) according to the aggregate content, gradation, shape, etc. Second, the RVE model is transformed to be a grayscale image and stored as a digital matrix. The quadtree mesh is partitioned automatically for simulation by SBFEM. There are only six types of unique subdomains, and the hanging node does not affect the simulation accuracy. The global stiffness matrix can be assembled directly according to the six subdomain stiffness matrices. Finally, the equivalent modulus is predicted by using the numerical homogenization method. Several numerical examples are employed to verify this model, and the results are compared with that of other methods. The result indicates that the proposed model can efficiently determine the equivalent modulus. Furthermore, the effect of the aggregate gradation, shape, porosity, and pore water are studied and analysed in this work. The proposed model is potential and helpful in predicting the mechanical properties of concrete or other composite materials.

Tetra hybrid nanofluids are significant due to their unique properties like thermal and electrical conductivity enhancement, increased heat transfer, and improved fluid flow characteristics. This attempt proposes a tetra hybrid cross nanofluid model with the implementation of cubic autocatalysis in the context of blood flow passing through a stenosis artery. The model includes the effects of nanofluid, magnetic field, thermal radiation, and the cubic autocatalysis mechanism. This research investigates the innovative application of cubic autocatalysis within the context of blood flow through a tetra hybrid cross nanofluid model, specifically designed to simulate conditions within a stenosis horizontal artery. The equations governing the fluid flow are solved using the bvp5c method, and the numerical solutions are obtained for various parameter values. Specifically, the cubic autocatalysis mechanism profoundly impacts the velocity and concentration profiles of the blood flow. The proposed model and the obtained results provide new insights into the physics of blood flow passing through stenosis arteries. They may have important implications for the diagnosis and treatment of cardiovascular diseases. This article has a unique combination of tetra hybrid cross nanofluid model, cubic autocatalysis, and blood flow passing through the stenosis artery. These facts are not typically studied together in the context of blood flow.

This study explains the conductive mechanism of C12A7:C from the perspective of crystal structure. C12A7:C is a carbon derivative of C12A7 and prepared by CaCO3 and Al2O3 in sealed graphite crucible through high-temperature sintering experiments. The main component was confirmed to be C12A7:C through X-ray diffraction inversion analysis. The four-probe method revealed that it is a semiconductor with conductivity of 4,339 S/m. A conductive model of C12A7:C crystal was established to study its conductive mechanism. Through theoretical calculations of the conductive structure model, the density of states and transfer function are important factors determining the conductivity of C12A7:C crystals. Based on the analysis of these two factors, C is the key to electron transfer in the C12A7:C crystal. Further research indicates that the C–C bond is the main form of C in C12A7:C crystals. These C–C bonds satisfy the formation conditions of conjugated systems and are key to the conductivity of C12A7:C crystals. Through simulation calculations, the volt ampere characteristic curve of C12A7:C exhibits Ohmic conductor characteristics. The conductivity of C12A7:C obtained through theoretical calculation is consistent with the experimental results. In conclusion, the conductivity of C12A7:C crystal is mainly due to the C–C conjugated system formed by carbon atoms in the crystal.

In this study, the thermo-flow behaviours of the spiral tube were examined using water and some nanofluids such as TiO2, Al2O3, Fe2O3, CuO, ZnO, and CeO2. The computational flow dynamic modelling of the spiral coiled tube was performed with ANSYS 20 software program. The k–ε model with a standard wall function was used to simulate the thermo-flow characteristics. The solution of the governing equations was performed using the discretization method of finite volume. The study was carried out considering the case of fluid-to-fluid heat transfer in turbulent conditions. The influence of different key design parameters such as Reynolds number, different nanofluids, and flow arrangements was of main interest. The volume concentration of the nanofluids is 1%. The experiments were performed at different Reynolds ranges (9,000, 14,000, 20,000, and 25,000). The outlet temperature values, heat transfer coefficient, coefficient of friction, Nusselt number values of water, and nanofluids were found and compared. It was found that the outlet temperature, heat transfer coefficient, and Nusselt number values of water were the lowest, while the coefficient of friction value was the highest compared to the nanofluids. Among the nanofluids, CeO was found to have the highest outlet temperature, heat transfer coefficient, and Nusselt number value, as well as the lowest coefficient of friction value. TiO2 was found to have the lowest outlet temperature (T out), the heat transfer coefficient value, and the highest coefficient of friction value. Al2O3 was found to have the lowest Nusselt number. In addition, Nusselt number values were obtained at different Dean numbers of water (2,200, 3,400, 4,900, 6,100, 7,350, and 8,600) and found to be compatible with previous studies. In addition, the coefficients of friction values of water at different velocities (0.18, 0.24, 0.41, 0.71, 0.95, 1.07, and 1.18) were obtained and found to be compatible with previous studies.

In the last few decades, tremendous effort is given to the production of various polymers and polymeric composites components through innovative polymer processing techniques. Fused deposition modeling (FDM) of polymers as a printing technique in additive manufacturing has been explored extensively due to its cost-effectiveness, manufacturing capabilities, flexibility in material selection, and dimensional accuracy. A few reviews of the literature have been done to investigate various applications for polymers, but none have focused on the research on commercial and in-house generated polymers and polymeric composites, particularly those made using the FDM printing technology. Consequently, the study data on the internal development of polymer and polymeric composite filament-based FDM printing is gathered and processed in this work. The work also highlights various types of polymeric composites and recycled polymeric composites with their detailed material characteristics. In addition, various applications of FDM printing of polymeric composites at the industrial scale and domestic level usage are highlighted as the potential to reduce carbon emission through the effective recycling process.

We have developed a novel rheo-optical measurement system based on two-dimensional polarization analysis, which can evaluate the rheological properties and structure of a complex fluid simultaneously. To assess the utility of the system, we used it to investigate the relationship between yield behavior and structural evolution in a TEMPO-oxidized cellulose nanofiber (T-CNF) suspension, which is a yield-stress fluid that has been actively studied in recent years. To analyze the structural evolution of a T-CNF suspension, stress-ramp tests were conducted. A two-step yield behavior was observed, and distributions of retardation and orientation axis varied dramatically with increasing shear stress. In particular, different distributions were observed in the three regions: after the first yield point, before the second yield point, and after the second yield point. In experiments with a low-concentration T-CNF suspension that exhibits no yield behavior, the retardation increased monotonically with increasing shear stress, and its distribution was uniform. It was demonstrated that the yield behavior and related structures can be analyzed from these results. More detailed structural mechanisms require various rheological tests using the developed system. However, the present insights demonstrate the valuable information provided by the developed rheo-optical measurement system, contributing essential knowledge for applications in various fields.

To investigate the impact of curing environments on the mechanical properties of coal gangue cementation (CGC), various curing methods were established, including standard bag curing, standard curing, natural sealing curing, natural curing, water curing, and varying curing ages. By examining the uniaxial compressive strength (UCS) and stress–strain relationship of CGC by applying axial loads, the influence mechanism was analyzed in terms of both physical and chemical reactions. Furthermore, a mechanistic structural model was established to illustrate the impact of the curing environment on the mechanical properties of CGC. The primary substances and reasons affecting the mechanical properties of CGC were analyzed through the use of scanning electron microscopy and X-ray diffraction techniques. Evaluation of influence factors on CGC mechanical properties by grey correlation degree. The findings indicate that curing temperature, humidity, and carbonization are the principal factors influencing the UCS. Maintaining constant temperature and humidity while isolating CO2 is conducive to improving the UCS. The hydration products, such as needle-like ettringite and white fibrous calcium silicate hydrogel, fill the internal voids of CGC and are the primary substances affecting UCS. The hydration products formed during standard curing and natural curing of CGC can undergo carbonation with CO2 to form CaCO3, which interacts with ettringite and hydrated calcium silicate to provide strength support for CGC. However, beyond a certain age, CO2 will progressively diminish the UCS; the larger the contact area and the longer the exposure time to the gel materials in CGC, the faster the UCS decreases.

This work presents a viscosity model based on the Giesekus equation. The model is shown to be more flexible than the Cross and Carreau models in representing the shear-thinning behavior of viscoelastic fluids. It has been investigated that the influence of the model parameters on the viscosity showed that the mobility parameter α plays a distinctive role in adjusting the inflection shape of the viscosity curve. The results show that the new model is able to accurately capture the shear-thinning behavior of polystyrene data, while the Cross and Carreau models tend to underestimate and overestimate the viscosity at the inflection point, respectively. It has been also shown that the Yasuda-type modification is also applicable to the proposed model. Moreover, the viscosity model has been applied to simultaneously fitting a polymeric liquid system and a particulate slurry system. The new viscosity model is a promising tool for modeling the shear-thinning behavior of viscoelastic fluids in a wide range of applications.

This study conducted a series of true triaxial hydraulic fracturing experiments on Longmaxi Formation shale. We investigated the interaction between internal factors and external factors on the inter-well interference of 400 mm cubic porous specimens. During dual wellbore fracturing at different formations, forming inter-well interference through secondary hydraulic fractures lead to a lower interference intensity and larger stimulated rock area. When adopting a three-layer well layout during three-wellbore fracturing, the vertical distance between the wells is shortened, activating more bedding planes. Regardless of a horizontal well placement with two wellbores or a three-dimensional two-layer well placement with three wellbores, increasing the vertical stress leads to more potent inter-well interference. There is no absolute positive correlation between the stimulated rock area and inter-well interference. It can be influenced by the presence of natural fractures within the formation that can even lead to a reduction in the stimulated area. When the well placement changes from two horizontal wellbores to three-dimensional two-layer sites with three wellbores and the vertical stress increases, the inter-well interference becomes stronger, but the stimulated rock area only increases by 22.6%. These findings provide crucial guidance for the hydraulic fracturing design of shale reservoirs.

In this study, solid waste titanium gypsum (TG) was used as raw material to design the basic mix ratio of aggregate, and TG artificial aggregate (TGA) was prepared based on alkali-activated cold bonding technology. The effects of different additives (slag, silica fume, and fly ash) on the properties of TGA were preliminarily investigated by using NaOH as activator in laboratory test, and the additives of TG aggregate were determined. Furthermore, the aggregate mix ratio was designed based on the additive, and the physical and mechanical properties, X-ray diffraction analysis, scanning electron microscopy analysis, and dry–wet cycle test of artificial aggregate were carried out. The results show that the artificial aggregate prepared by the same process and the aggregate prepared by silica fume as an additive has a high balling rate; it is technically feasible to use TG as the main raw material, silica fume as an additive, and NaOH as an activator to select a suitable mix ratio to prepare artificial aggregates. The microscopic test results reveal the internal products and structural degradation process of TG aggregate.

This study aims to develop composite plates using silkworm cocoon waste- and hybrid silkworm cocoon waste-reinforced polymer composite using epoxy resin as a matrix to replace synthetic fibers in bulletproof plates. The fabrication involved mixing 70 g of silkworm cocoon waste with 240 g of resin and 70 g of ultra-high molecular weight polyethylene, followed by cold compression molding. Tensile and impact tests on the resulting samples, using a standardized 9 mm projectile, showed a tensile strength of 107.4 MPa and an elastic modulus of 1240.3 MPa. With a back face signature (BFS) of 21.25 mm, the samples effectively intercepted the projectile, satisfying the stringent U.S. National Institute of Justice standard 0101.06, which specifies a maximum BFS of 44 mm. In comparison with hemp woven materials, silkworm cocoon waste has proven to be a promising substitute for both tensile and impact evaluations, attracting considerable interest and underscoring its role as a reinforcing agent for national fiber. This research has significant implications for industries and applications requiring affordable, lightweight, and efficient safeguards against ballistic dangers. Ultimately, it contributes to the progress of ballistic protection methods by encouraging exploration into innovative, bio-inspired, and sustainable materials capable of achieving superior impact resistance.

This study discusses the experimental results of the ballistic impact on thick-layered carbon fibre-reinforced polymer (CFRP), glass-based FRP (GFRP), and Kevlar-based FRP (KFRP) composite plates. Ten 10 mm plates of each type were manufactured via the hand lay-up and vacuum bagging techniques to produce plates with a thickness of 2 mm each, which were bonded together using epoxy adhesive and hot pressed at 75°C to obtain thick layered plates with a total thickness of 20 mm each. The specimen plates were tested according to the NIJ 0108.01 standard in a special firing room using a 9 mm G2 Elite handgun with a full metal jacketed round nose 9 mm × 19 mm Mu1-TJ bullets moving at a velocity of approximately 358 m/s. The results indicated that no total penetration occurred on any of the plates. The bullets were destroyed by impact, and the penetration depths of the CFRP, GFRP, and KFRP plates were 11.10, 9.95, and 22.22%, respectively. The layered structures in these plates appear to have changed the penetration behaviour compared with previous studies. In this study, delamination was the primary failure mode.

Stress path change has a great relationship with the effect of deformation and strength of rock. However, the underground rock body is in the engineering environment where the stress field, seepage field, and other fields are coupled to change, the law of fluid flow in the rock body is complex and variable. The change in the stress field has an important effect on the seepage characteristics of rock body; therefore, it is necessary to study the pattern of rock permeability evolution pattern by different stress paths. This study is based on the study of limestone, conducting triaxial unloading seepage mechanics experiments, the evolution of permeability properties of limestone specimens was analyzed based on the test results. The results show that in the conventional triaxial loading seepage test, the permeability of the limestone decreases before the rock stress reaches the peak intensity and increases after that. Increasing axial pressure unloading surrounding pressure compression section, permeability loss rate and effective stress are in line with the changing law of Gaussian distribution function. Under the action of constant axial pressure unloading surrounding pressure, with the increase in unloading amount, the permeability rate of change appears to increase slowly, and in the late stage of unloading section, the permeability rate of change appears to surge. Unloading section permeability change rate and cumulative unloading amount are in line with the law of change of the exponential function. Creep unloading pressure seepage test found that unloading pressure stage strain-time and permeability-time evolution characteristics are in line with the exponential rule of change. The experimental results of this study can provide an important experimental and theoretical basis for the permeability analysis of low-permeability rock body under complex stress conditions in underground engineering.

Unsaturated polyester resin (UPR) is the most versatile liquid polymer with a wide range of applications in every aspect of the industry but it has low impact strength, low elongation at break, and low toughness. Its mechanical properties can be enhanced with the addition of an optimum percentage of nano-silica fillers by using ASTM polymer test standards, which have been followed by various research groups. For this research, enhanced mechanical properties of the resin have been tested for 0.5, 1, 2, 3, and 4% amount by weight fraction of the nano-silica as fiber nanomaterial. The sugar cane bagasse ash was collected from the Wenji Sugar Factory and extracted with the required size of the particle, which is 10 nm. The ability of extraction is used to manipulate the particle size as the researcher needs. The aim is to determine the enhanced mechanical properties of the UPR by the addition of optimum nano-silica particles. Nanoparticles have the effect of filling porous regions, crack path deflection, and crack bridging capability of the material, which provides good adhesion with the matrix to increase the mechanical properties of composite materials. Experimental result dictates that 0.5% nano-silica addition with 10 nm particle size performs best by enhancing the mechanical properties of composite material up to 30.45% for tensile, 33% for compression, 17.8% for flexural, a slightly 10% improvement for impact test and it shows an overall 27% better performance than the pure UPR. Thermal stability and glass transition temperature were not influenced by the addition of nano-silica.

In order to study the basic road performance and the mechanism of red mud modified asphalt, Marshall test, rut test, freeze-thaw splitting test, and immersion Marshall test were carried out for matrix asphalt mixture and red mud modified asphalt mixture, and molecular simulation technology was introduced to study the mechanism of red mud modified asphalt. The results showed that the penetration rate of red mud modified asphalt was lower than that of the matrix asphalt, and the softening point of asphalt was significantly improved after the addition of red mud, and the mixing of red mud reduced the asphalt ductility greatly. The intensity ratio (test strength ratio; TSR) of the freeze-thaw test of red mud modified asphalt under 3, 5, 7, 9, and 11% was increased by 13.18, 11.22, 13.54, 12.01, and 8.45%, respectively, compared with the matrix asphalt mixture, and the dynamic stability value increased by 127.23, 176.87, 200.99, 96.23, and 12.95%; the residual stability value of the immersion Marshall test increased obviously. Generally, the research of red mud modified asphalt is quite worthy, it can solve the problem of aluminum ore slag and reuse of resources, and provide a new way to extend the industrial chain.

Aggregate is the basic component of concrete, and its shape and surface properties largely determine the mechanical properties and durability of concrete. In order to further study the mesoscopic influence of aggregate shape on concrete interfacial phase, this study focuses on two aggregate shapes, circular and polygonal, and the elastic modulus and hardness of interfacial phase of specimens with different aggregate shapes were obtained by nano-indentation technology, and the mesoscopic component partition was quantified. Based on Gaussian statistical theory, the distribution model of nanomechanical properties of each phase was established, and the influence of aggregate shape on mechanical properties was studied by SEM test. The results show that (1) The width of the interfacial zone of natural rounded aggregate (∼50 μm) is slightly smaller than that of polygonal aggregate (∼60 μm), and the modulus of elasticity and hardness of the interfacial zone corresponding to the rounded aggregate (e.g., interfacial transition zone (E,H) ∼ (23.65 GPa, 0.9 GPa)) are larger than that of the interfacial zone of polygonal aggregate (interfacial transition zone (E,H) ∼ (21.66 GPa, 0.73 GPa)), indicating that the micromechanical properties of the interfacial zone of the circular aggregate are better than those of the polygonal aggregate; (2) The hydration products in the transition zone of the interface of different shapes of aggregates are almost the same, indicating that the influence of the shape of aggregates on the performance of concrete is mainly due to its own geometric characteristics. Based on the findings of the study, the direction of future research can focus on modeling with further refinement of the influence of aggregate shape parameters, such as shape factor and surface roughness, on the performance of concrete, so as to facilitate more accurate prediction and regulation of the performance of concrete. This study provides theoretical references for the design of aggregate proportioning and the simulation technology of fine data values in actual projects, and also provides theoretical basis and technical support for the standardization and performance evaluation of concrete materials.

The performance of bituminous materials is often evaluated using rheological properties measured within the linear viscoelastic region. If there is a univocal temperature dependence of all the relaxation times, data obtained in different operating conditions can be translated onto a logarithmic scale where they partially overlap and merge into a single master curve. This is the well-known time–temperature superposition principle that has been successfully applied for decades. However, the empirical nature of the method has led to many different procedures being used for the graphical construction of the master curve. In addition, the continuously increasing calculating power has led to new approaches, such as the simultaneous modelling of the represented viscoelastic function. Losing track of the basic statements of the method is the hidden drawback of this wide range of available protocols with the risk of artefacts and incongruences being introduced in the construction of the master curves. This review summarizes these basic statements together with the empirical and phenomenological approaches developed over the years. The aim of this study is to help the reader in choosing the most appropriate method to build the master curves. Although the subject of the review is of general application, the field of bitumen is focused on.

River sand was consumed in large quantities, and alternatives to river sand were urgently needed. There are a large number of natural resources of aeolian sand in western China. Aeolian sand was prepared into aeolian sand concrete (ASC). It can greatly reduce the consumption of river sand and inhibit the process of desertification to protect the environment. ASC is a new type of concrete material prepared by using aeolian sand as fine aggregate. To clarify the chloride ion transport behaviour in the ASC under long-term natural immersion, the aeolian sand was 100% substituted for the river sand to prepare the full ASC with three water–binder ratios. The ASC was naturally immersed in 3 and 6% NaCl solutions for a long time, and nuclear magnetic resonance and microscopic scanning electron microscopy techniques were used. The change rule of chloride ion content at different depths of the ASC was studied, and its microstructure characteristics under different erosion times were analysed. The results showed that the free chloride ion concentration at different depths of the ASC increased with increasing water–binder ratio, immersion time, and chloride concentration. After soaking in the salt solution, the hydration products in the ASC reacted with chloride ions to form Friedel salt, which filled the internal pores and microcracks of the ASC, improved its interface transition zone structure, and increased the compactness of the test piece. The porosity of the three groups of ASC with different water–binder ratios decreased by 0.95, 1.03, and 1.15% after soaking in 6% salt solution for 12 m. To study the diffusion law of chloride ions in ASC, combined with influencing factors such as temperature, humidity, D value, deterioration effect and chloride ion combination, Fick’s second law was modified, and a chloride ion diffusion model of ASC with high accuracy was established, with a fitting correlation number above 0.93, which provided a reference for the research and application of ASC in saline areas.

Formaldehyde is one of the most common indoor air pollutants that seriously damage human health. It is of significant importance to effectively remove indoor formaldehyde. In this work, a novel cement-based composite with ZIF-8@TiO2-coated activated carbon fibers (TiO2-ACFs) was prepared and shown to remove the indoor formaldehyde effectively. TiO2 was coated on ACFs via atomic layer deposition, and then ZIF-8 was grown on the surface of TiO2-ACFs. The ZIF-8@TiO2-ACFs were then mixed with cement slurry and thus formed a cement-based composite, which exhibited excellent formaldehyde removal performance. In particular, if assisted with UV light, the removal efficiency for formaldehyde by the cement-based composite showed an obvious increase.

In this work, an Ag–Ti2SnC composite was fabricated by the hot-pressing sintering method, and the erosion behavior of Ag–Ti2SnC with volume percentages of 10–40% was studied at a load voltage of 10 kV. The arc life and breakdown current were observed at about 31–36 ms and 39 A, respectively. The cathode spot traveled the fastest on the surface of the Ag–40 vol% Ti2SnC composite. Due to emission center model, the temperature of the minor protrusions on the cathode surface increased, resulting in Ag ions, Ti ions, and Sn ions being generated. Combining with the ionized oxygen, Ag2O, AgO, TiO2, and SnO2 were formed on the eroded Ag–Ti2SnC surface after arc erosion. The research results will broaden the application range of Ag–Ti2SnC electrical contact material and enrich the arc erosion mechanism.

Carbon fiber-reinforced polymer (CFRP) exhibits aging effects over time that can degrade its mechanical properties. In this study, a systematic investigation was carried out to investigate the effect of distilled water aging on the mechanical properties of CFRP composite patch bonded on Al 2024-T3 plates. We built a finite element model to analyze the effect of water absorption by the composite and the adhesive on the effectiveness of the composite patch repair. Using the experimentally evaluated mechanical properties of CFRP and Araldite adhesive subjected to distilled water immersion, finite element simulations were validated. The experimental observations deduce that there was a negligible effect of moisture absorption on the bulk mechanical properties of CFRP and adhesive over time. However, a significant effect of moisture absorption was observed on the elasto-plastic behavior of both CFRP and adhesive. Consequently, the numerical simulations suggest that the moisture absorption reduces the bonded composite patch repair efficiency attributed to an increase in the plasticity around the crack front and accordingly increases the damage in the adhesive layer. This study attempts to provide guidelines on the severity of damage caused by water absorption on the performance of structures repaired with composite patches.

This study investigated the influence of microbead dosages (0, 5, 10, 15, and 20%) on the frost resistance of expanded polystyrene (EPS) concrete. Five groups of EPS concrete specimens were prepared and subjected to rapid freeze–thaw tests. The freeze–thaw deterioration of EPS concrete was assessed using macroscopic indicators, including mass loss, strength loss, and dynamic elastic modulus loss. The underlying deterioration mechanism was revealed through the analysis of the EPS particle–matrix interface. A concrete damage plasticity model of EPS concrete based on damage mechanics theory was established. The results indicate that the addition of microbeads increased the strength of EPS concrete by 38–53%, reduced the strength attenuation after freeze–thaw damage by 8.1%, and improved the frost resistance level by 10–60 grades. The optimal dosage of microbeads is 15% of the cementitious material. The interfacial transition zone gaps in EPS concrete with added microbeads after freeze–thaw cycles are smaller, contributing to a more complete hydration reaction. The freeze–thaw damage model established in this study accurately reflects the freeze–thaw damage law of EPS concrete and provides a reference for studying the mechanical properties of EPS concrete under freeze–thaw cycles. The research findings of this study can enhance the strength and service life of EPS concrete, expanding its application scope as a structural material. The study provides valuable insights for future research and engineering applications related to the frost resistance of EPS concrete.

The presence of karst formations significantly impacts the load-bearing capacity of pile foundations in karst geological environments, posing a challenge to their design. This study investigated the bearing characteristics of karst pile foundations using the physical model test and numerical analysis. First, the influence of cave height and span on the bearing capacity of pile foundations is examined using model tests. The results demonstrate that the height of karst caves greatly affects the bearing capacity of karst pile foundations. Subsequently, numerical analysis further explores the bearing characteristics of these foundations. It reveals that as the top load on pile increases, an arch-shaped tensile damage zone forms at the top of karst cave and gradually expands. The rock failure in this area leads to a decrease in adhesion between rock strata and pile foundation, consequently reducing its load-bearing capacity. Finally, experimental results are compared with numerical results to validate consistency and mutual verifiability between physical model tests and numerical analyses. The outcomes of the research provide valuable insights for designing rock-socketed pile foundations in similar karst areas.

Interfaces of cementitious layers have widely existed in construction projects, and they are the weakest part of the whole building. In this article, laser scanning and ultrasonic pulse, splitting tensile, and semi-disc fracture tests were carried out to study the bonding performance of cementitious layers. Different performance metrics, such as splitting tensile bond strength, ultrasonic pulse velocity, and attenuation of first arrival, were used to evaluate the bonding characteristics of the concrete layers. The results revealed that the parameters of the interface curve decreased, and the mechanical properties of the interface became weaker with an increase of the interval time. The amplitude of the first wave was more sensitive to the presence of the interface than the ultrasonic pulse velocity. Finally, the relationships between the performance metrics were analyzed. The fracture toughness of model I and mode II was highly correlated with the parameters of the micromorphology of the layered concrete, and the correlation coefficient is not less than 0.9511. The fracture toughness of mode I was strongly related to the splitting tensile strength, with a correlation coefficient of not less than 0.9744. This study was useful for the future study of the mode I and I fracture performance, the morphology, and other physical properties of cementitious layers.

The fabrication of robust and high-performance graphene-based electrodes on engineering plastics has garnered significant attention in recent years. In this study, we present a novel methodology to produce porous graphene structures derived from epoxy resin (EP) utilizing a straightforward laser direct-scribing process. Under the influence of a CO2 laser in an ambient atmosphere, EP undergoes a transformation to yield laser-induced graphene (LIG-APP/EP). Furthermore, this LIG-APP/EP was employed to construct an electrode for lithium-ion batteries, which exhibited outstanding electrochemical performance. Notably, the initial charge and discharge capacities of the LIG-APP/EP electrode material were recorded at 976 and 1,452 mAh g−1, respectively, with a coulombic efficiency of 67.2%. Such impressive performance can be ascribed to the hierarchical porous architecture of LIG-APP/EP and the concurrent doping with nitrogen (N) and phosphorus (P) atoms. Given these findings, LIG-APP/EP demonstrates significant potential for applications in advanced electrochemical systems. This innovative approach also offers profound implications for the sustainable recycling of discarded engineering plastics.

Fiber reinforced polymer (FRP) have the advantages of high strength, corrosion resistance, and low density, which are widely used to serve as tray products in bolt support systems. As a key component, the low mechanical load-bearing capacity of trays significantly limits their widespread application. Besides, there is no corresponding theoretical calculations and strength analysis methods for the structural design. The aim of this study is to optimize the tray structure and improve its load-bearing capacity. Through theoretical calculations and finite element numerical analysis, the effect of inner surface taper and stiffener height on the load-bearing capacity of the tray under the application of constant axial force is investigated. The results show that first of all, the larger the inner surface taper is, the better the load capacity of the tray. Second, the special-shaped truncated cone type displayed better load capacity than the stiffener tray. Third, the higher the design height of the stiffener is, the smaller the deformation and shear stress on the top of the inner surface of the tray, and better load capacity is achieved. We believe that this study provides theoretical guidance for the structural design of high-performance FRP trays.

To investigate the damage evolution and failure mechanisms of fiber-reinforced composite materials under complex conditions, this study conducted in situ X-ray computed tomography (CT) compression and tensile tests on plain weave two-dimensional woven SiC/SiC composite materials. The obtained CT in situ image data captured the behavior of materials during loading and after failure. Using the image reconstruction of CT data, the actual microstructure and damage evolution of the material under six consecutive loading levels were accurately revealed. Three-dimensional visualization models of the composite material were established using image processing software to analyze the damage evolution under compression and tension, and the failure mechanisms were compared. The results showed that the compression and tension failure mechanisms of SiC/SiC composite materials were similar, with the transverse cracking of the matrix being the first mode of damage, followed by delamination between layers and longitudinal matrix cracking of fiber bundles. Specifically, in terms of compression failure, the strength of the fiber bundle itself has a greater influence, and fiber fracture is the main cause of ultimate material failure. On the other hand, the primary cause of tensile failure is the presence of porosity defects generated during material fabrication. Consequently, the tensile material fails earlier and can withstand lower loads.