Bending Conditions Research Articles

Double-network gel electrolyte with high electrolyte retention for flexible high-voltage Zn-air batteries

The zinc-air battery (ZAB) exhibits promising potential for application in wearable devices due to its high energy density, low cost, and safety features. However, the semi-open structure of ZAB accelerates the evaporation of battery electrolytes and poses a potential risk of leakage. Herein, a novel polyacrylamide-co-sodium p-benzenesulfonate and carboxymethyl cellulose (PAS-CMC) double-network gel electrolyte was synthesized and utilized in a flexible ZAB. The prepared PAS-CMC exhibits exceptional electrical conductivity (315.53 mS cm−1), mechanical properties, as well as electrolyte retention capacity. The ZAB assembled by alkaline PAS-CMC exhibits remarkable stability during circulation for over 120 h. Compared with the traditional alkaline PAS-CMC electrolyte, the open-circuit voltage (2.03 V), operating voltage (1.90 V) and power density (164.3 mW cm−2) of the ZAB assembled by the acid-alkaline PAS-CMC prepared by the “sandwich” strategy have been significantly improved, showing excellent flexibility under various bending conditions without any degradation in performance. Furthermore, the interaction mechanisms between PAS-CMC/H2O and PAS-CMC/Zn were further elucidated by DFT calculation, thereby establishing a theoretical foundation for high-voltage flexible ZAB.

Construction of amphoteric hydrogel electrolytes with charge modification: An investigation of ion migration mechanism and antibacterial property

Some challenges still hinder the advancement of hydrogel electrolytes, such as low ionic conductivity and restricted flexibility, which obstacle the effective integration of supercapacitors for flexible wearable devices. We developed an amphoteric hydrogel electrolyte with a highly ionic conductivity of 46.64 mS·cm−1, 927.32% of tensile strain and compressive strain to 85% in ambient air. Through lignin sulfomethylation and chitosan quaternization, abundant charge groups were introduced to the structure of hydrogel electrolyte to achieve charge modification. These charged groups not only promoted the dissociation of KOH, but also formed ion transport channels to enhance the migration of K+ and OH–. Note that the hydrogel also had significant antibacterial activity, enhancing its practical applicability. Moreover, the flexible supercapacitor constructed with this hydrogel electrolyte showed excellent capacitive performance, achieving a notable specific capacitance of 192.6 F·g−1 and a high energy density of 45.2 Wh·kg−1 under a current density of 0.5 A·g−1. In addition, the flexible supercapacitor also demonstrated remarkable rate performance and cycle stability, which maintained nearly constant coulombic efficiency (99.7%) and retaining 86.1% of capacitance retention after 10,000 charge–discharge cycles. Moreover, the flexible supercapacitor maintained stability under bend and load conditions, showing good deformation adaptability.

Achieving consistency of flexible surface acoustic wave sensors with artificial intelligence

Flexible surface acoustic wave technology has garnered significant attention for wearable electronics and sensing applications. However, the mechanical strains induced by random deformation of these flexible SAWs during sensing often significantly alter the specific sensing signals, causing critical issues such as inconsistency of the sensing results on a curved/flexible surface. To address this challenge, we first developed high-performance AlScN piezoelectric film-based flexible SAW sensors, investigated their response characteristics both theoretically and experimentally under various bending strains and UV illumination conditions, and achieved a high UV sensitivity of 1.71 KHz/(mW/cm²). To ensure reliable and consistent UV detection and eliminate the interference of bending strain on SAW sensors, we proposed using key features within the response signals of a single flexible SAW device to establish a regression model based on machine learning algorithms for precise UV detection under dynamic strain disturbances, successfully decoupling the interference of bending strain from target UV detection. The results indicate that under strain interferences from 0 to 1160 με the model based on the extreme gradient boosting algorithm exhibits optimal UV prediction performance. As a demonstration for practical applications, flexible SAW sensors were adhered to four different locations on spacecraft model surfaces, including flat and three curved surfaces with radii of curvature of 14.5, 11.5, and 5.8 cm. These flexible SAW sensors demonstrated high reliability and consistency in terms of UV sensing performance under random bending conditions, with results consistent with those on a flat surface.

Study of the large bending behavior of CNTs using LDTM and nonlocal elasticity theory

The general expressions for vertical deflection, horizontal displacement, and strain energy in a bent cantilevered carbon nanotube (CNT) are derived herein under a uniformly distributed load. This derivation employs nonlocal elasticity theory, crucial for understanding nanoscale mechanics due to size effects, and accounts for the nonlinear relationship between bending curvature and deflection under large bending conditions, a novel contribution. In the limiting cases, our expressions for large bending give the corresponding expressions reported in the literature for small bending. Additionally, we introduce the Laplace-Differential Transformation Method (LDTM) for the first time, providing efficient solutions to explore the influence of parameters like aspect ratio and small-scale factors on CNT bending behavior. Comparison with the analytical method validates the accuracy and efficacy of LDTM, offering a rapid solution for nonlinear equations. Our findings reveal that strain energy deviates more prominently from quadratic behavior in CNTs with high aspect ratios, while small-scale parameters have a pronounced effect on CNTs with smaller aspect ratios. These results will be relevant to designing and applying the nanoscale-sized cantilevered CNTs used in MEMs/NEMs.

Engineering estimate of plastic collapse loads for cracked pipe bends under in-plane and out-of-plane bending

Nuclear power plant piping systems frequently encounter complex loads due to factors like internal pressure, self-weight, structural supports, and operational conditions. Within these systems, pipe bends play a crucial role in releasing energy through deformation. Cracks pose a risk to the integrity of the system, necessitating the calculation of the plastic collapse load for cracked pipe bends. This study presents estimations for the plastic collapse load of cracked pipe bends under pure out-of-plane bending moments and simultaneous in-plane and out-of-plane bending moments. Cracks located in the intrados, extrados, and crown of pipe bends were considered. The estimations for plastic collapse load are proposed based on the observed similarity between plastic collapse load and plastic deformation under both in-plane and out-of-plane bending conditions. For combined in-plane and out-of-plane bending moment conditions, circular and parabolic relationships have been proposed for a straightforward plastic collapse load prediction. Additionally, the estimations for plastic collapse loads were derived from the results of finite element analysis conducted on crack-free pipe bends, demonstrating its applicability to cracked pipe bends as well.

Enhanced Stability-Based Hydroxymethyl Cellulose/Polyacrylamide Interpenetrating Dual Network Hydrogel Electrolyte for Flexible Yarn Zinc-Ion Batteries

As the field of wearable electronics continues to boom, the demand for flexible energy storage devices continues to grow. However, the development of soft energy supply devices with excellent stability is still a challenging task. Traditional hydrogel electrolytes are prone to mechanical deformation, which makes it difficult to maintain the functional stability of flexible yarn due to its short battery life and low wear resistance. Here, we developed a reversible energy-dissipating dual-network hydrogel electrolyte. The hydroxymethyl cellulose (CMC)/polyacrylamide (PAM) hydrogel electrolyte has a tensile deformation of 2700% and a high ionic conductivity of 6.37 × 10−2 S cm−1. The specific capacity of the assembled CMC/PAM-based yarn cell was 170 μAh cm−1 at 1 mA cm−1 and 73.14% after 100 cycles. The excellent performance is attributed to the crosslinked double network structure, in which the introduction of carboxyl groups is conducive to the improvement of hydrophilicity and ionic conductivity. The hydrogen bond and reversible CMC macromolecular chain can be restored after stress relief, which greatly improves the toughness of the material. Even under different bending angles and repeated bending conditions, zinc yarn batteries still have outstanding mechanical properties and cycle stability (71.28% specific capacity after 100 cycles), showing broad application prospects in wearable smart textiles.

УПРУГОПЛАСТИЧЕСКИЙ ИЗГИБ

Within the framework of the planar cross-section hypothesis, the construction of calculation formulas for determining stresses and deformations in cross- sections of an elastoplastic member under conditions of planar transverse bending is considered. The rod material works according to a bilinear tensile pattern and resists both tension and compression equally. The cross-section of the member, which is constant along its length, has one vertical spine of symmetry. The condition of ultimate equilibrium of an elastoplastic rod is recorded. Calculation formulas for normal stresses on platforms in the cross-sections of the member, for shear stresses, for normal stresses on horizontal platforms when loading a member with a distributed load are given. curvature of the curved axis of the rod on the elastic and elastoplastic sections of the rod is determined. Differential equations of the curved axis of the rod on the elastic and elastoplastic sections of the rod are given. The residual normal and shear stresses are determined after the member has been completely unloaded. The differential equations of the curved axis of the member after it has been completely unloaded are recorded. The obtained design relations can find practical application in the design of an elastoplastic member from both the strength condition and the stiffness condition.

Variability of strength and stiffness assessment for non-profile beam structures

Introduction. Traditional ways to increase the structural strength and stiffness of beams are now almost exhausted, and optimization of production and operation technologies is mostly based on the use of new materials and increasing their reliability as bearing elements of a complex geometric profile. Bearing elements of building structures operate under high loads and, even despite their predominantly static nature, experience a complex volumetric stress and strain state, which can scarcely ever be confirmed empirically and statistically.Aim. To propose an approach to assessing the strength and stiffness of beam structures operating under conditions of transverse bending of a complex geometric profile.Materials and methods. Classical energy methods, including Castigliano, Maxwell–Mohr and Vereshchagin methods (moment area method), have been used to assess the strength and stiffness of non-profile beam structures, initial parameters, differential equations of the deflection curve.Results. The similarity parameters (fitting criteria) of Mises–Hencky and Zhurkov reflect the behavior of a brittle or plastic beam material reasonably well. These characteristics are proposed to be combined in the Arrhenius–Zhurkov durability functions.Conclusions. The dependencies given in the calculations can be recommended for improving the flexural static and fatigue strength, as well as the stiffness of the bearing elements of building structures.

Bismuth Ferrite-Silver Nanowire Flexible Nanocomposites for Room-Temperature Nitrogen Dioxide Sensing.

Nitrogen dioxide (NO2) is a major pollutant, causing acid rain, photochemical smog, and respiratory damage. The annual safe limit is 50 parts per billion (ppb), while concentrations exceeding 1 part per million (ppm) can result in respiratory ailments. Conventionally, n-type metal oxide semiconductors operating at elevated temperatures have been utilized for NO2 detection. Recently, p-type semiconductors with their hole accumulation layer, rapid recovery post-gas exposure, and good humidity tolerance are being investigated as potential NO2 sensors, once again working at elevated temperatures. In this work, a room-temperature (27 ± 2 °C) NO2 sensor is demonstrated by using a nanocomposite based on p-type bismuth ferrite (BFO) nanoparticles and silver nanowires (Ag NWs). This nanocomposite is capable of sensing a NO2 gas concentration of up to 0.2 ppm. The BFO nanoparticles are synthesized via a sol-gel route followed by sintering at 500 °C to form the crystalline phase. Nanocomposites are obtained by formulating a dispersion of the BFO nanoparticles and Ag NWs, followed by direct writing on both flexible and rigid substrates. The Ag NWs act as the conducting pathway, reducing the overall electrical resistance and thus enabling room-temperature operation. X-ray diffraction, scanning electron microscopy, and surface area studies provide phase information and surface morphology, and the porous nature of the film helps in room-temperature gas adsorption. The current-voltage and gas-sensing behavior are studied to obtain the optimized molar ratio (4:1 BFO/Ag NWs) for the sensor. The sensor deposited on poly(ethylene terephthalate) (PET) also works under a bent condition, indicating good flexibility. Rapid NO2 sensing was achieved in a BFO-Ag/PET device with response/recovery times of 7/8.5 s and 12/15 s in straight and bent geometries, respectively. Additionally, a good sensitivity of 30 to 60% was achieved for the BFO-Ag/PET device across 100 to 1000 ppb of NO2. The development of a nanocomposite combining an active sensing element (BFO) and a charge-transport element (Ag NWs) opens up a multitude of other application areas.

Bent functions satisfying the dual bent condition and permutations with the $$(\mathcal {A}_m)$$ property

AbstractThe concatenation of four Boolean bent functions $$f=f_1||f_2||f_3||f_4$$ f = f 1 | | f 2 | | f 3 | | f 4 is bent if and only if the dual bent condition $$f_1^* + f_2^* + f_3^* + f_4^* =1$$ f 1 ∗ + f 2 ∗ + f 3 ∗ + f 4 ∗ = 1 is satisfied. However, to specify four bent functions satisfying this duality condition is in general quite a difficult task. Commonly, to simplify this problem, certain relations between $$f_i$$ f i are assumed, as well as functions $$f_i$$ f i of a special shape are considered, e.g., $$f_i(x,y)=x\cdot \pi _i(y)+h_i(y)$$ f i ( x , y ) = x · π i ( y ) + h i ( y ) are Maiorana-McFarland bent functions. In the case when permutations $$\pi _i$$ π i of $$\mathbb {F}_2^m$$ F 2 m have the $$(\mathcal {A}_m)$$ ( A m ) property and Maiorana-McFarland bent functions $$f_i$$ f i satisfy the additional condition $$f_1+f_2+f_3+f_4=0$$ f 1 + f 2 + f 3 + f 4 = 0 , the dual bent condition is known to have a relatively simple shape allowing to specify the functions $$f_i$$ f i explicitly. In this paper, we generalize this result for the case when Maiorana-McFarland bent functions $$f_i$$ f i satisfy the condition $$f_1(x,y)+f_2(x,y)+f_3(x,y)+f_4(x,y)=s(y)$$ f 1 ( x , y ) + f 2 ( x , y ) + f 3 ( x , y ) + f 4 ( x , y ) = s ( y ) and provide a construction of new permutations with the $$(\mathcal {A}_m)$$ ( A m ) property from the old ones. Combining these two results, we obtain a recursive construction method of bent functions satisfying the dual bent condition. Moreover, we provide a generic condition on the Maiorana-McFarland bent functions $$f_1,f_2,f_3,f_4$$ f 1 , f 2 , f 3 , f 4 stemming from the permutations of $$\mathbb {F}_2^m$$ F 2 m with the $$(\mathcal {A}_m)$$ ( A m ) property, such that the concatenation $$f=f_1||f_2||f_3||f_4$$ f = f 1 | | f 2 | | f 3 | | f 4 does not belong, up to equivalence, to the Maiorana-McFarland class. Using monomial permutations $$\pi _i$$ π i of $$\mathbb {F}_{2^m}$$ F 2 m with the $$(\mathcal {A}_m)$$ ( A m ) property and monomial functions $$h_i$$ h i on $$\mathbb {F}_{2^m}$$ F 2 m , we provide explicit constructions of such bent functions; a particular case of our result shows how one can construct bent functions from APN permutations, when m is odd. Finally, with our construction method, we explain how one can construct homogeneous cubic bent functions, noticing that only very few design methods of these objects are known.

Experimental investigation of bending fatigue behaviors for T-shaped welded joint

A fatigue test was conducted on a T-shaped welded joint under three-point bending conditions. Prior to the test, the geometry of the weld toe on both sides of the specimen was observed and measured. The locations of Fiber Bragg Gratings (FBG) strain gauges were determined based on the weld toe’s geometric features. During the experiment, a 2-level load spectrum block of cyclic loading was applied, resulting in distinct beach marks on the fatigue fracture surface. The stress-time history of the weld toe’s geometric features was monitored. After the test, the fatigue fracture was observed and measured, the influence of the crack path on the crack propagation rate was analyzed, and the influence of the crack propagation pattern on the stress evolution in the nearby area was studied. The experimental results show that the multiple cracks initiation positions have strong relationship with the characteristic points of weld toe morphology. Based on the Linear Elastic Fracture Mechanics (LEFM) theory and the concept of varying remote stress, four crack propagation simulation patterns were constructed and carried out. The results show that the varying remote stress has an more important influence on life prediction of welded joints, while the threshold mainly affect the life prediction of the early stage.

Development of bone surrogates by material extrusion-based additive manufacturing to mimic flexural mechanical behaviour and fracture prediction via phase-field approach

Background and objectiveThe limited availability of human bone samples for investigation leads to the demand for alternatives. Bone surrogates are crucial in promoting research on the intricate mechanics of osseous tissue. However, solutions are restricted to commercial brands, which frequently fail to faithfully replicate the mechanical response of bone, or oversimplified customised simulants designed for a specific application. The manufacturing and assessment of reliable bone surrogates made of polylactic acid via material extrusion-based additive manufacturing are presented in this work. MethodsAn experimental and numerical study with 3D-printed dog-bone and prismatic specimens was carried out to characterise the polymeric feedstock and analyse the influence of process parameters under three-point bending and quasi-static conditions. Besides, three porcine rib samples were considered as a reference for the development of the artificial bones. Bone surrogates were manufactured from the 3D-scanned real bone geometries. In order to reproduce the trabecular and cortical bone, a lattice structure for the infill and a compact shell surrounding the core were employed. Infill density and shell thickness were evaluated through different printing configurations. Additionally, a computational analysis based on the phase-field approach was conducted to simulate the experimental tests and predict fracture. The modelling considered homogenisation of the infill material. ResultsOutcomes demonstrated the potential of the presented methodology. Maximum force and flexural stiffness were compared to real bone properties to find the optimal printing configuration, replicating the flexural mechanical behaviour of bone tissue. Certain configurations accurately reproduce the studied properties. Regarding the numerical model, strength and stiffness prediction was validated with experimental results. ConclusionsThe presented methodology enables the manufacturing of artificial bones with accurate geometries and tailored mechanical properties. Furthermore, the described modelling strategy offers a powerful tool for designing bone surrogates.

A Flexible Long-Wave Infrared Radiation Modulator Integrated with Electrochromic Behavior for Dual-Band Camouflage.

Electrochromic devices (ECDs), which are capable of modulating optical properties in the visible and long-wave infrared (LWIR) spectra under applied voltage, are of great significance for military camouflage. However, there are a few materials that can modulate dual frequency bands. In addition, the complex and specialized structural design of dual-band ECDs poses significant challenges. Here, we propose a novel approach for a bendable ECD capable of modulating LWIR radiation and displaying multiple colors. Notably, it eliminates the need for a porous electrode or a grid electrode, thereby improving both the response speed and fabrication feasibility. The device employs multiwalled carbon nanotubes (MWCNTs) as both the transparent electrode and the LWIR modulator, polyaniline (PANI) as the electrochromic layer, and ionic liquids (HMIM[TFSI]) as the electrolyte. The ECD is able to reduce its infrared emissivity (Δε = 0.23) in a short time (resulting in a drop in infrared temperature from 50 to 44 °C) within a mere duration of 0.78 ± 0.07 s while changing its color from green to yellow within 3 s when a positive voltage of 4 V is applied. In addition, it exhibits excellent flexibility, even under bending conditions. This simplified structure provides opportunities for applications such as wearable adaptive camouflage and multispectral displays.

High‐Resolution Printing‐Based Vertical Interconnects for Flexible Hybrid Electronics

AbstractFlexible hybrid electronics (FHE) is an emerging area that combines printed electronics and ultra‐thin chip (UTC) technology to deliver high performance needed in applications such as wearables, robotics, and internet‐of‐things etc. The integration of UTCs on flexible substrates and the access to devices on them requires high resolution interconnects, which is a challenging task as thermal and mechanical mismatches do not allow conventional bonding methods to work. To address this challenge, the resource‐efficient, area‐efficient, and low‐cost printing routes for obtaining vertical interconnection accesses (VIAs) are demonstrated here. It is demonstrated how high‐resolution printers (electrohydrodynamic and extrusion‐based direct‐ink writing printers) can be used for patterning of high‐resolution, freeform, vertical conductive structures. To access the transistors on UTCs, the VIAs, obtained using conventional photolithography and plasma etching steps, are filled with conductive silver nanoparticle‐based ink/paste using high‐resolution printers. Comprehensive studies are performed to compare and benchmark in terms of: i) the printing speed and throughput of the printers, ii) the electrical performance of vertically connected transistors in UTCs, and iii) the electrical performance stability of FHE system (interconnects and UTCs) under mechanical bending conditions. This in‐depth study shows the potential use of printing technologies for development of high‐density 3D integrated FHE systems.

Oxygen Vacancy-Induced Low-Valence reactive species enabling High-Efficient nonenzymatic glucose detection

NiCo2O4 (NCO), a typical spinel-type transition metal oxide, emerges as a promising candidate for non-electroenzymatic glucose sensors because of its stable structure and low overpotential. However, the practical applications of NCO are hindered by its limited intrinsic activity for glucose detection. Herein, we intentionally incorporated low-valence redox species into NCO nanowires by modulating the oxygen vacancies (VO-NCO NWs), thereby facilitating glucose oxidation reactivity. The concentration of low-valence species increases with the generated oxygen vacancies, which enriches the reactive redox species and enhances the intrinsic electrical conductivity, thereby improving the catalytic activity. Consequently, the optimized VO-NCO NWs exhibit highly efficient glucose detection with high sensitivity up to 19.65 mA·mM−1·cm−2, which is 4.6 times higher than that of the pristine NCO NWs, as well as a low limit of detection (LOD) of 0.15 μM. Furthermore, a flexible miniaturized three electrode (FMTE) assembled with optimized VO-NCO NWs provides a high sensitivity of 15.89 mA·mM−1·cm−2 and a low LOD of 0.18 μM in synthetic sweat. Under various bending conditions, the FMTE demonstrates good mechanical flexibility, with no discernible alterations in the response current. These findings provide a promising protocol for the dynamic monitoring of sweat composition to reveal human physiological health status.

Structural–Phenomenological Concept and Acoustic-Emission Diagnostics of Composite Stringers under Three-Point Bending Conditions

Structural–Phenomenological Concept and Acoustic-Emission Diagnostics of Composite Stringers under Three-Point Bending Conditions

Experiment and simulation study on the functional fatigue of shape memory alloy beam actuators

The functional fatigue behavior of shape memory alloy (SMA) beam actuators is gaining importance as their utilization in engineering applications becomes more widespread. However, research on the functional fatigue behavior of SMA beam actuators under bending conditions is not as extensive as that on SMA wires. In this paper, an experimental study and theoretical analysis of the functional fatigue behavior of SMA beam actuators were conducted. A measuring method for bending deflection and an automatic thermal cyclic test bench was designed. A series of functional fatigue tests were conducted on SMA beam actuators under different bias load conditions and the functional fatigue patterns were obtained. The material damage factor is defined and calculated through specimen tests. By incorporating the damage factor to modify the existing constitutive model, a model considering functional fatigue and tension-compression asymmetry is obtained. Finite element analysis (FEA) is performed based on this modified model to simulate the actuating performance of SMA beam actuators and to compute the deflection at different numbers of cycles. Additionally, a small parameter study on the actuator shape is conducted using FEA. By comparing the FEA results with functional fatigue experimental data, the effectiveness of the modified model is validated, demonstrating its capability to describe functional fatigue and predict actuator lifespan.

Development and comprehensive evaluation of a dual-port textile UWB MIMO antenna for biomedical use

In this paper, a textile two-port multi-input multi-output (MIMO) half-circle antenna with corrugated borders is designed and fully analyzed for nearfield ultra-wideband biomedical diagnostic applications. The orthogonal polarization technique is introduced for mutual coupling reduction, signal quality, and imaging accuracy improvement. A low pass filter with significant out-of-band rejection is inserted between the two MIMO structural elements to improve the isolation from element to element. For simple system integration, A 50 ohms feed coplanar waveguide is suggested for each element. The entire antenna is constructed using textile materials, with the radiating element composed of conductor fabric. The substrate, on the other hand, is crafted from cotton material which possesses a relative permittivity of and a tan δ value of 0.025. The size of each antenna element has low-profile dimensions of 40 × 40 × 0.3 mm3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$${mm}^{3}$$\\end{document}. The measured results obtained demonstrate an extremely broad bandwidth extends from 2.5 GHz to 12 GHz. Omnidirectional radiation pattern is obtained, with 6 dBi maximum gain and 96% efficiency. In order to ensure flexibility, a range of bending conditions were analyzed, and the durability was assessed through wash ability testing. Safety was confirmed by measuring the specific absorption rate. Furthermore, time domain and MIMO performance assessments were performed to ensure its suitability for imaging systems.

Bendable, lamellar MXene membrane electrodes with diverse diffusion pathways for potential application in miniaturized capacitive deionization devices

Flexible devices have shown great application potential in portable and miniaturized devices. However, work on flexible electrodes for capacitive deionization (CDI) has not been well developed due to the issues of desalination property, processability, and availability under actual bending conditions. Herein, we constructed a kind of flexible lamellar MXene membrane by assembling Ti3C2Tx sheets with both crumpled and perforated structures and studied their desalination performance in conventional planar and bent configurations. The crumpled and perforated features in Ti3C2Tx (C-P-TC) nanosheets could optimize the in-plane and out-of-plane diffusion channels of the stacked samples, respectively, effectively improving the accessibility of membranes. As a result, the desalination performance of such C-P-TC electrodes was superior to that of those assembled from crumpled or perforated sheets alone. Significantly, this flexible C-P-TC electrode still showed excellent performance at real bend deformation, which possessed not only almost the same CDI capacity as the traditional planar configuration but also good cycling stability. This work not merely proposes an alternative strategy to improve the CDI performance of lamellar MXene electrodes by regulating the nanostructures of channels but also confirms their effective deionization ability under real bent state, greatly facilitating the potential use of flexible electrodes in miniaturized CDI devices.

Behavior of soil slopes reinforced with composite-structural piles

Slope stability is a key problem in geotechnical engineering, often addressed through reinforcement methods, such as reinforced concrete piles. However, they have limitations, including high costs and underutilization of steel and concrete properties. This study proposes a new type of composite-structural pile, combining two types of materials with different mechanical behaviors. Centrifuge model tests were performed to explore the deformation and failure behavior of slopes reinforced with the composite-structural pile under vertical loading conditions. The strains and soil pressure of the composite-structural pile were measured to analyze its stress characteristics. The composite-reinforced slope exhibited progressive failure from the top to the toe under vertical loading conditions, featuring a curved, discontinuous slip surface. The slope deformation increased with increasing load and developed to deformation localization. A clear coupling effect was observed between slope deformation localization and local failure. Finite element analysis was performed to evaluate the mechanical characteristics of the composite-structural pile under bending conditions. The strain distribution on the cross-section of the pile was linear for different material parameters. Based on these findings, a method for calculating the stress and strain of composite-structural piles was developed. Centrifuge model tests validated the reliability of the proposed method.