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Na+/vacancy ordering in sodium‐ion layered oxide cathodes is widely believed to deteriorate the structural stability and retard the Na+ diffusion kinetics, but its unexplored potential advantages remain elusive. Herein, we prepared a P2‐Na0.8Cu0.22Li0.08Mn0.67O2 (NCLMO‐12 h) material featuring moderate Na+/vacancy and transition‐metal (TM) honeycomb orderings. The appropriate Na+/vacancy ordering significantly enhances the operating voltage and the TM honeycomb ordering effectively strengthens the layered framework. Compared with the disordered material, the well‐balanced dual‐ordering NCLMO‐12 h cathode affords a boosted working voltage from 2.85 to 3.51 V, a remarkable ~20 % enhancement in energy density, and a superior cycling stability (capacity retention of 86.5 % after 500 cycles). The solid‐solution reaction with a nearly "zero‐strain" character, the charge compensation mechanisms, and the reversible inter‐layer Li migration upon sodiation/desodiation are unraveled by systematic in situ/ex situ characterizations. This study breaks the stereotype surrounding Na+/vacancy ordering and provides a new avenue for developing high‐energy and long‐durability sodium layered oxide cathodes. [ABSTRACT FROM AUTHOR]

Highlights This paper investigates a honeycomb sandwich structure that draws inspiration from the craft of origami. A specific folding pattern was applied to the honeycomb to create the origami‐based re‐entrant honeycomb (ORH), aimed at improving the energy absorption properties of the sandwich structure. The study on the energy absorption properties of structures under low‐velocity impact (LVI) utilized both experimental and numerical approaches. The energy absorption properties of the sandwich structure were examined by conducting LVI tests with different impact energy and then compared to the mechanical properties of the traditional re‐entrant honeycomb sandwich structures (TRHSS). Additionally, a refined finite element model has been established and its accuracy verified. Numerical studies were conducted to explore the effects of structural parameters on the energy absorption properties of ORH sandwich structure (ORHSS). The results show that the ORHSS exhibited a significant reduction in peak force when subjected to LVI, in contrast to the TRHSS. Furthermore, the ORHSS exhibit significant efficiency in energy absorption. Enhancing the wall thickness t$$ t $$ or folding angle V/H$$ V/H $$ can significantly improve the energy absorption properties of the ORHSS, thereby boosting the honeycomb's contribution to this process. This optimization results in an improved absorptive effect of the structure. The findings offer new recommendations for developing lightweight absorbent materials with potential applications across various industries. A novel composite sandwich structure serves as an efficient device for absorbing energy. This sandwich structure exhibits excellent cushioning and energy absorption capabilities. Changing geometric parameters can enhance the impact performance of the structure. A larger folding angle V/H$$ V/H $$ makes the core more prone to deformation. The greater the forward length V$$ V $$ of the ORH, the lower specific energy absorption (SEA) of the ORHSS. [ABSTRACT FROM AUTHOR]

For the harsh entry environment and higher thermal protection requirements, two structures of three‐dimensional woven gradient thermal protection materials were designed and prepared with the deep space exploration thermal protection system as the object. They are 3D orthogonal woven, 2.5D layer‐to‐layer angle interlock woven, 2.5D layer‐layer angle interlock woven structure(OLL) composite and 3D orthogonal woven, angle 2.5D layer‐to‐layer angle interlock woven, honeycomb structure(OLH) composite. Two materials were prepared and examined by ablation in an oxygen‐acetylene flame. A three‐dimensional macroscopic ablation model was established on the basis of the experiment, and the model was verified to be accurate and effective, which can well respond to the pyrolytic ablation process of the materials. The two designed materials are applied to the outsole of MSL by simulation, and the three‐dimensional response during the entry into Mars is simulated and analyzed in comparison with the thermal protection performance of PICA material. Both materials show better thermal protection than PICA and can be used as a reference in the selection of thermal protection materials. Highlights: Two kinds of 3D gradient woven thermal protection materials are designed.A 3D thermal protection system response model is established.The three‐dimensional response during entry was analyzed.Thermal protection of the material is superior to that of PICA. [ABSTRACT FROM AUTHOR]

Studies of graphene show that robust chemical bonds such as covalent bonds with trigonal‐planar atoms afford layered atomic 2D crystals possessing unique properties. Although layered molecular crystals are of interest to diversify elements and structures of 2D materials, the structural diversity of molecules as well as weak intermolecular interactions inevitably makes the design to be one‐off and individual. We herein report a versatile method to assemble layered molecular crystals. By developing a D3‐symmetry host at vertices to form a honeycomb layer, a diverse range of layered 2D host–guest crystals were obtained. Substituents on the host, elements/structures of the guest, the stereochemistry of the host and types of intercalants were diversified, which should allow for 6×32×3×2 combinations for structural diversification. [ABSTRACT FROM AUTHOR]

Microfluidic valves play a key role within microfluidic systems by regulating fluid flow through distinct microchannels, enabling many advanced applications in medical diagnostics, lab‐on‐chips, and laboratory automation. While microfluidic systems are often limited to planar structures, 3D printing enables new capabilities to generate complex designs for fluidic circuits with higher densities and integrated components. However, the control of fluids within 3D structures presents several difficulties, making it challenging to scale effectively and many fluidic devices are still often restricted to quasi‐planar structures. Incorporating mechanical metamaterials that exhibit spatially adjustable mechanical properties into microfluidic systems provides an opportunity to address these challenges. Here, systematic computational and experimental characterization of a modified re‐entrant honeycomb structure are performed to generate a modular metamaterial for an active device that allows us to directly regulate flow through integrated, multiplexed fluidic channels "one‐at‐a‐time," in a manner that is highly scalable. A design algorithm is presented, so that this architecture can be extended to arbitrary geometries, and it is expected that by incorporation of mechanical metamaterial designs into 3D printed fluidic systems, which themselves are readily expandable to any complex geometries, will enable new biotechnological and biomedical applications of 3D printed devices. [ABSTRACT FROM AUTHOR]

This study extensively characterizes the out‐of‐plane stiffness and energy harvesting capabilities of a newly proposed anti‐trichiral hierarchical auxetic honeycomb structure, both mechanically and deformationally. By introducing a design concept based on the anti‐trichiral honeycomb (ATCH), a structure with superior out‐of‐plane load‐carrying capacity and excellent auxeticity is achieved. To validate the finite element model, compression simulations are conducted. Comparative investigations into the morphing characteristics and energy harvesting performance between the novel structure and the ATCH are performed. Additionally, the influence of various parameters on the comprehensive performance of the novel auxetic structure is explored. It has been found that the angle φ is most sensitive to the auxetic properties, while the ratio k significantly impacts energy absorption. This research advances the design of novel auxetic structures for potential applications in protective engineering. [ABSTRACT FROM AUTHOR]

Recently, plasmonic metasurfaces have emerged as a platform for topological photonics, exhibiting both advantages of plasmon‐induced tight confinement of local field and topological robustness. Most previous works regarding plasmonic systems are limited to the first‐order topologies and only a few studies dealt with higher‐order topological states in honeycomb lattices. Moreover, second‐order topologies of square lattice plasmonic systems have not yet been studied. This work presents second‐order topological corner states in the square lattices of metallic nanoparticles (NPs) with various symmetries, taking two different C4 and glide symmetries as examples. Their unit cells are obtained from nonprimitive cells, consisting of four equal spheroidal NPs, by expanding (or shrinking), rotating, and resizing. Bulk bands and spectral functions of the unit cells calculated by using the coupled dipole method well agree with COMSOL simulation results, revealing the accuracy of the numerical calculations as well as the experimental realizability of the systems. Second‐order topological corner states and their robustness against structural disorder are numerically shown for three different square lattices. This work will trigger extensive investigations to open a new realm of topological metasurfaces with promising applications. [ABSTRACT FROM AUTHOR]

Background: Basosquamous carcinoma (BSC) is a rare and aggressive nonmelanoma skin cancer (NMSC) that exhibits features of both BCC and squamous cell carcinoma (SCC). The gold standard for diagnosis is histopathological examination. BSC is often challenging to diagnose and manage due to its mixed histological features and potential for aggressive behavior Aim: To identify specific features aiding clinicians in differentiating BSCs using non‐invasive diagnostic techniques. Methods: We conducted a retrospective descriptive, monocentric study of the epidemiological clinical, dermoscopic, and reflectance confocal microscopy (RCM) features of histopathologically proven BSCs diagnosed between 2010 and 2023. A total of 192 cases were selected. Results: The study population consisted of 17 men (60.9%). Total 95.8% of patients at the time of diagnosis were ≥50 years. BSC occurred in the head and neck area in 124 cases (63.1%) of which 65 (33.9%) were in the H‐zone. For 47.4% of patients, BSC presented as a macule with undefined clinical margins (43.3%). Dermoscopic images were available for 98 cases: the most common parameter was the presence of whitish structureless areas (59 [60.2%]), keratin masses (58 [59.2%]), superficial scales, and ulceration or blood crusts (49 [50%] both). Vessels pattern analysis revealed hairpin vessels (exclusively) and linear irregular vessels as the most frequent (55 [56.1%] both). RCM examination was performed in 21 cases which revealed specific SCC features such as solar elastosis (19 [90.5%]), atypical honeycomb pattern (17 [89%]), proliferation of atypical keratinocytes (16 [80%]) combined with BCC' ones as bright tumor islands (12 [57.8%]), and cleft‐like dark spaces (11 [53.4%]). Discussion: Our study reflects the largest cohort of BSCs from a single institution. We described an incidence rate of 4.7%, higher than reported in the Literature, with the involvement of patients ≥50years in almost 96% of cases and an overall male predominance. At clinical examination, BSC was described as a hyperkeratotic macule with undefined clinical margins with one or more dermoscopic SCC' features, whereas the presence of typical BCC aspects was observed in less than 10% of cases, differently from what was previously reported. At RCM analysis, BSCs presented with an atypical honeycomb pattern with proliferation of atypical keratinocytes, hyperkeratosis, and in nearly 55% of patients, bright tumor islands with cleft‐like dark spaces. Conclusion: The distinctive dermoscopic patterns, along with the RCM features aid in the differentiation of BSCs from other NMSCs. [ABSTRACT FROM AUTHOR]

Both the nacre‐like bionic microstructure and the spiral laminated bionic configuration exhibit superior damage‐tolerance characteristics. On the basis of this observation, the design concept of the bionic helical‐interlayer configuration is innovatively integrated into the design of a bionic nacre‐like honeycomb structure. By systematically studying different spiral angles of honeycomb's interlayer stacking forms, their influence on the structural performance is deeply discussed with four‐point bending tests. Mechanical samples are carefully prepared using short carbon fiber reinforced polyamide composites (i.e., PA6‐CF) through conventional fused filament fabrication (FFF) 3D printing technology, where the accuracy and reliability of the designed bio‐inspired samples are ensured. The experimental results reveal significant improvements in bending strength and elastic modulus across various bionic nacre‐like honeycomb spiral structures compared to uniformly overlap configurations. In particular, the SH‐7.5 sample shows a remarkable 35.47% increase in bending strength and a 65.10% increase in elastic modulus over the SH‐11.25 sample. SEM‐based microstructural analyses are carried out to further explore the fracture mode of the carbon fibers, implied the helical configuration adopted in the nacre‐like honeycomb structure enhances the flexural resistant ability of the PA6‐CF composites. The findings above bear important guiding significance and reference value for the design of lightweight and high damage‐tolerance composite structures. Highlights: A novel bio‐inspired structure is implemented to improve the mechanical performance of fused filament fabricated polyamide composites, where the bionic spiral helical configuration is integrated into high‐fracture‐resistance nacre‐like honeycomb structures.Mechanical testing results indicate that a helix angle under 10° results in a significant improvement in the structural performance of flexural strength.Microstructural analysis reveals that the helical configuration enhances the load‐bearing functionality of reinforcing carbon fibers in the printed polyamide composites.FFF 3D printing enables further implementation of the proposed bio‐inspired novel structure for lightweight and damage‐tolerant composite applications with high customization demands. [ABSTRACT FROM AUTHOR]

Designing a functional end plate for the proton exchange membrane fuel cell (PEMFC) is a challenging task since the structure that simultaneously satisfies uniform contact pressure and lightweight features must be achieved. To design an end plate for both requirements, a multi‐objective topology optimization model of the PEMFC based on the concept of equivalent stiffness is established with the aim of maximum stiffness and minimum root mean square (RMS) of contact displacement. Based on the final topology, the filled honeycomb‐based end plates with excellent mechanical properties and energy absorption effects are optimized through the particle swarm optimization algorithm (PSO). The results demonstrate that the end plate mass is reduced by 39.5% and the stress distribution is more uniform. The standard deviation of pressure decreases by 30.8% compared to the original model data. The proposed optimization method is helpful in the design of future end plates. [ABSTRACT FROM AUTHOR]

Two‐component catalysts have garnered significant attention in the field of catalysis due to their ability to inhibit Ni sintering. In the present work, honeycomb‐structuralstructured Al2O3‐supported Ni and B were prepared to enhance coke tolerance during dry reforming of methane (DRM). Transmission electron microscopy (TEM) results revealed that the average particle sizes on Ni/Al2O3 and Ni‐0.16B/Al2O3 were 7.6 nm and 4.2 nm, respectively, indicating that B can effectively inhibit Ni sintering. After a 100‐hour reaction, the conversion of CH4 and CO2 on Ni/Al2O3 decreased by approximately 5 %, whereas on Ni‐0.16B/Al2O3, there was no significant decrease in CH4 and CO2 conversion, with values of approximately 81.6 % and 87.2 %, respectively. In situ DRIFT spectra demonstrated that Ni‐0.16B/Al2O3 enhanced the activation of CO2, thus improving the catalyst‘s stability. A Langmuir–Hinshelwood–Hougen–Watson (LHHW) model was developed for intrinsic kinetics, and the resulting kinetic expressions were well‐fitted fit to the experimental data, with R2 values exceeding 0.9. ActivationThe activation energies were also calculated. The outstanding stability of Ni‐0.16B/Al2O3 can be attributed to its stable honeycomb structure and B′s ability to significantly inhibit Ni sintering, reduce catalyst particle size, and enhance coke tolerance. [ABSTRACT FROM AUTHOR]

Achieving reversible O‐redox through the formation of electron–holes on O could hold the key to a new generation of high energy density Na‐ion cathodes. However, to date, it has only been demonstrated in a small handful of cathode materials and none of these materials exploit the dual benefit of high voltage transition metal redox and O‐redox, instead relying on Mn3+/4+ capacity close to 2 V vs Na+/Na. Here, a new Na‐ion cathode exhibiting electron–holes on O is demonstrated, P2‐type Na0.67Li0.1Ni0.3Mn0.6O2, which also utilizes the high voltage Ni3+/4+ redox couple to deliver the highest reported energy density among this class of compound. By employing a low Li content and avoiding honeycomb ordering within the transition metal layer, it is possible to stabilize the hole states, and the high voltage plateau is preserved in Na0.67Li0.1Ni0.3Mn0.6O2 over cycling. [ABSTRACT FROM AUTHOR]

Highlights The mechanical properties of the carbon fiber and glass fiber composite honeycomb sandwich structure were studied through compression experiments. The influence of different aluminum honeycomb edge lengths, upper and lower panel thickness, aluminum honeycomb thickness, and loading speed on the compression failure load of carbon fiber composite laminates sandwich structure is analyzed. The influence of different aluminum honeycomb edge lengths and thicknesses on the compression failure load of glass fiber composite laminates sandwich structure was studied. The results show that the thickness of the panel has a significant effect on the failure load of the carbon fiber composite laminate sandwich structure, and the loading speed has a significant effect on the failure load of the carbon fiber composite laminate sandwich structure. The greater the loading speed, the greater the value of the failure load. The edge length and thickness of the aluminum honeycomb have a certain effect on the damage load of the carbon fiber composite laminates sandwich structure, but the influence on the mechanical properties of the glass fiber composite laminates sandwich structure is much greater. The compression performance of composite sandwich structures was experimentally studied. The influence of composite panel thickness was studied. The influence of aluminum honeycomb edge length and thickness was studied. The influence of loading speed was studied. [ABSTRACT FROM AUTHOR]

In this work, a technique for constructing a three‐dimensional (3D) skeleton of hexagonal boron nitride (h‐BN) using sugar as the fulcrum and preparing composites by embedding in the epoxy (EP) in a vacuum environment is proposed. The study of thermal conductivity (TC) in polymer composites is conducted through a blend of techniques: laser flashing, theoretical modeling, and finite element simulation. The h‐BN skeleton exhibits a honeycomb structure through the scanning electron microscopy findings. Further investigation using finite element simulation demonstrates that conductive networks are formed by the h‐BN skeleton within the composites, leading to a notable enhancement in TC. Specifically, the composite for h‐BN/EP reaches a TC of 2.25 W/m K when composed of 52 vol% h‐BN. A dielectric loss of 0.008 for the composite with the same h‐BN loading shows a considerable improvement. The compressive yield strength of the 3D h‐BN/EP composites reached 312 MPa at 5 vol% h‐BN loading. [ABSTRACT FROM AUTHOR]

This study investigates the crashworthiness of biomimetic composite thin‐walled tubes under quasi‐static axial crushing, focusing on the effects of geometric structure and fiber orientation. The thin‐walled tubes, inspired by honeycomb structures, were manufactured using carbon fiber composites through multi‐cavity preform mold method. Quasi‐static crushing tests and CT scanning observation were conducted to characterize the mechanical response, crashworthiness mechanisms and energy absorption capacity of the thin‐walled tubes. Results demonstrated excellent energy absorption capacities across all configurations, with the C‐0/45 configuration achieving the highest specific energy absorption at 115.03 kJ/kg. The optimal crushing energy absorption process for thin‐walled tubes involves achieving high peak loads and maintaining high load levels. Sustaining high loads requires progressive and stable damage without the formation of extensive intermediate cracks between different plies (indicative of strong interlaminar shear strength). The structural integrity of the uncrushed sections must remain intact without significant damage during the crushing process. Fiber orientation parallel to the loading direction enhances peak load levels and interlaminar shear strength between plies, but may compromise circumferential stiffness and structural stability. The influence of geometric configuration is primarily manifested in the progressive and stable crushing phase, where the tube requires sufficient space to accumulate its own debris without causing damage to the uncrushed thin‐walled structure. Highlights: Structures and fiber orientation boost crashworthiness in biomimetic composite tubes.Biomimetic structures were produced using a multi‐cavity preform mold method.CT scans were conducted to characterize the energy absorption mechanisms.Composite tubes demonstrated excellent energy absorption capacity of 115 kJ/kg. [ABSTRACT FROM AUTHOR]

The three‐dimensional (3D) boron nitride (BN) thermal conductive networks, crafted through layer‐by‐layer assembly, hold tremendous potential for the development of insulating thermal interface materials (TIMs) with exceptional thermal conductivity. Nevertheless, maintaining the thermal conductive stability of this structure type during application remains a considerable challenge. Herein, initially, the honeycomb networks of boron nitride/nanodiamond (ND/kBN) with interlocking interfaces were prepared by electrostatic self‐assembly and ice template method. Subsequently, thermal conductivity composites of flexible silicone rubber (VQM) were acquired through vacuum‐assisted infiltration. The composites demonstrated improved through‐plane thermal conductivity with 1.03 W/(m K) at a 9.9 vol% content of ND/kBN while exhibiting relatively ideal dielectric properties. More importantly, the thermal conductive properties of the composites still maintain at 96.1% and 91.9%, respectively, even after undergoing 30% compressive deformation for 1 h and being bent 300 times. This study presents a novel strategy that not only improves the thermal conductivity of composites but also ensures the reliability of their applications. Highlights: Nanodiamond (ND) is anchored onto the kBN surface by electrostatic self‐assembly.ND/kBN filler honeycomb network with an interlocking interface was prepared.Flexible composites with high thermal conductivity (TC) were prepared.The composites exhibit excellent TC stability after experiencing deformation. [ABSTRACT FROM AUTHOR]

A 14‐year‐old girl presented with a facial‐pigmented lesion suspicious of melanoma clinically and dermoscopically. In vivo, reflectance confocal microscopy (RCM) findings excluded melanoma by revealing typical epidermal honeycomb and cobblestone patterns. Well‐defined follicular contours were seen at the dermal–epidermal junction; there were no elongated, “medusa head‐like” follicular protrusions or folliculotropism, which are classical findings seen in lentigo maligna. With this report, we aim to demonstrate the significance of utilizing RCM technology in difficult to diagnose lentiginous pigmented lesions. [ABSTRACT FROM AUTHOR]

Honeycomb‐layered oxides are a class of cathode materials for sodium‐ion batteries with great potential due to their high voltage and high capacity. However, the structural instability and voltage fading during cycling limit their practical application. Herein, it is revealed that Te substitution into Na3Ni2SbO6 induces a new dual‐honeycomb structure, which can elevate the average discharge voltage of the cathode materials from 3.2 to 3.8 V with improved cycle stability and alleviated voltage decay. Synchrotron operando X‐ray diffraction demonstrates that Te substitution can suppress the O3−P3−O1‐phase transition during charge and discharge processes effectively, benefited from the strong TeO covalent bonds. The resulted Na2.2Ni2Sb0.2Te0.8O6 cathode exhibits a high capacity retention of 70.9% after 1000 cycles at 1C, with an elevated operating voltage of ≈3.8 V. Theoretical calculations reveal that the introduced TeO bonds break the symmetric distribution of charge in Ni/Sb honeycomb structure and elevate the operation voltage by increased valence band width. Proper Te substitution can promote the rate and cycle capability of the cathode by suppressing phase transition and decreasing the bandgap. [ABSTRACT FROM AUTHOR]

In the process of ion insertion/deinsertion, VS2 is prone to volume expansion or even structural collapse leading to capacity decrease and low coulomb efficiency (CE), which hinders its practical application. In this paper, VS2/rGO composites were prepared by solvent method. The rGO firmly locks VS2 in its honeycomb structure, effectively preventing the volume expansion or even structural collapse of the electrode during charging and discharging. The layered structure of VS2 and the high conductivity of rGO speed up the lithium ion transport and achieve the cycling stability of the battery. The results show that the starting capacity of the VS2/rGO anode material is 1190/959 mAh g−1, and the starting CE is 80.57 %. It is worth noting that after 150 cycles, the specific discharge/charge capacity of the material can be maintained at 764/736 mAh g−1. The improved electrochemical properties of the VS2 anode are due to the presence of rGO in the material, thus optimizing the structural stability and electrical properties of the composite. [ABSTRACT FROM AUTHOR]

The development of high‐energy‐density aqueous zinc‐ion batteries requires the preparation of cathodes with a thick layer of active material. However, the insulating nature and dissolution of vanadium‐based oxides lead to low areal capacity (0.1,1 mA h cm−2) during the charge/discharge cycle. Herein, V2O5 nanospheres are generated by anchoring onto the laser‐induced graphene (LIG) conductive network through defect‐induced adsorption, resulting in the formation of pomegranate‐like V2O5@LIG composites. The unique and abundant defect structure in the honeycomb LIG can trigger the formation of uniform V2O5 nanospheres with high specific surface area and interact electronically with V2O5 to enhance the electrical conductivity of the cathode materials up to four orders of magnitude. In contrast to conventional carbon materials that can cause steric hindrance for ion transport, the micropores within LIG shorten the ion transport path through the cathode. Concurrently, the pomegranate‐like encapsulated structure effectively prevents cathode material corrosion. Under a high‐loading mass of 17.1 mg cm−2, the full cell is stably cycled for 200 cycles, possessing a 92.5% capacity retention, and achieving a high areal capacity of 6.05 mA h cm−2. [ABSTRACT FROM AUTHOR]

Polyolefins and polyolefin elastomers (POEs) are widely used in various applications due to their unique properties. However, their use in 3D printing has been limited due to challenges such as excessive softness, shrinkage, warpage, and poor mechanical properties. In this study, two strategies were employed to enhance the performance of POEs in 3D printing. First, POE was blended with 10%, 30%, and 50% percentages of linear low‐density polyethylene (LLDPE) to improve the material's mechanical properties and printability. Second, a specialized printer called a pneumatic feeding fused granule fabrication (FGF) printer was used. This printer allows for the direct printing of material granules, eliminating the need for filaments and resolving filament‐related problems. To evaluate the quality of the printed parts, tensile tests, dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM) imaging were conducted. The printed parts showed desirable tensile properties (with approximately 3000% elongation at break and approximately 12 MPa tensile strength). Compression tests were also conducted on cubic structures with varied composition ratios and printing patterns such as grid, triangle, and honeycomb. The main purpose of this research was to explore the energy absorption capabilities of the printed blends. The results of our study showed that blending POE with LLDPE improved printability, tensile strength, energy absorption, and compressive properties. The blend with 50% LLDPE and honeycomb structure exhibited the best compressive and energy absorption properties. Highlights: Blending of POE and LLDPE using melt mixing with three different blending ratios.Successful 3D printing with the fused granule fabrication technique.Investigating mechanical properties, microstructure, and thermal analysis.125% increase in ultimate tensile strength by increasing LLDPE.Achieving the highest energy absorption for the 3D printed honeycomb structure. [ABSTRACT FROM AUTHOR]

Highlights Novel Stitched Foam‐filled Honeycomb Sandwich (SFHS) panels have been fabricated using vacuum‐assisted resin transfer molding to address the weak interfaces between the face sheets and the core in the Foam‐filled Honeycomb Sandwich (FHS) panel. The SFHS panels have shown better load‐bearing capacity and performance characteristics compared to FHS panel after Low‐Velocity Impact (LVI) tests. After the LVI test, MATLAB image processing was used to analyze the impact damage areas and failure mechanisms. In addition, Machine Learning regression algorithms were employed to predict the optimal amount of energy absorbed during low‐velocity impact testing of fabricated panels with a maximum impactor drop height of 700 mm. The results indicated that nylon yarn stitching significantly improved energy absorption and interfacial behavior compared to unstitched honeycomb panels. This research also revealed that SFHS1 panels with adjacent honeycomb cell stitching are more impact resistant, provide increased load carrying capacity, and are cost‐effective. These panels can be utilized by modern engineers to increase economy, durability, and functionality in industrial, automotive, and construction applications. Stitched Foam Filled Honeycomb Sandwich (SFHS) panels, manufactured via resin transfer molding, and eliminates weak interfaces between the face sheets and core. SFHS panels outperformed unstitched panels in load‐bearing and energy absorption during low‐velocity impact, as confirmed by MATLAB image analysis showing reduced damage and failure. Machine learning algorithms particularly polynomial regression model predicted maximum absorption energy precisely with 99.9% accuracy, close to experimental results. SFHS panels can be used in automotive and industrial applications due to their through‐thickness stitching. [ABSTRACT FROM AUTHOR]

Na+/vacancy ordering in sodium‐ion layered oxide cathodes is widely believed to deteriorate the structural stability and retard the Na+ diffusion kinetics, but its unexplored potential advantages remain elusive. Herein, we prepared a P2‐Na0.8Cu0.22Li0.08Mn0.67O2 (NCLMO‐12 h) material featuring moderate Na+/vacancy and transition‐metal (TM) honeycomb orderings. The appropriate Na+/vacancy ordering significantly enhances the operating voltage and the TM honeycomb ordering effectively strengthens the layered framework. Compared with the disordered material, the well‐balanced dual‐ordering NCLMO‐12 h cathode affords a boosted working voltage from 2.85 to 3.51 V, a remarkable ~20 % enhancement in energy density, and a superior cycling stability (capacity retention of 86.5 % after 500 cycles). The solid‐solution reaction with a nearly “zero‐strain” character, the charge compensation mechanisms, and the reversible inter‐layer Li migration upon sodiation/desodiation are unraveled by systematic in situ/ex situ characterizations. This study breaks the stereotype surrounding Na+/vacancy ordering and provides a new avenue for developing high‐energy and long‐durability sodium layered oxide cathodes. [ABSTRACT FROM AUTHOR]

Smart honeycombs are becoming the novel structural strategy for next‐generation devices and equipments. Unfortunately, traditional surface‐coating, structural immersing, and 3D printing approaches still face significant challenges in combining structural customization and performance multifunctionality. Herein, a brand‐new processing strategy is developed to construct graphene‐based smart honeycombs by stacking and deploying laser‐induced graphene (LIG) layers with alternatively inserted adhesives. Through tuning key parameters, various LIG‐enabled smart honeycombs (LIG‐HC) can be assembled with scalable areal dimension and thickness, variable cell sizes and shapes, as well as patternable graphene clusters. By further understanding the process‐dependent structural stability and electrical conductivity, multifunctional characteristics are systematically explored, including anisotropic mechanical, electrical, piezoresistive, and electromagnetic performance. To finally demonstrate the unique honeycomb multifunctionally applied in fields of aviation, an intelligent LIG‐HC enabled aircraft‐wing model is representatively constructed for performing anti‐/de‐icing, high‐temperature warning, flame retardancy, pressure and vibration monitoring, as well as electromagnetic shielding and stealth. [ABSTRACT FROM AUTHOR]

Artificial 1D and 2D lattices have emerged as a powerful platform for the emulation of lattice Hamiltonians, the fundamental study of collective many‐body effects, and phenomena arising from non‐trivial topology. Exciton‐polaritons, bosonic part‐light and part‐matter quasiparticles, combine pronounced nonlinearities with the possibility of on‐chip implementation. In this context, organic semiconductors embedded in microcavities have proven to be versatile candidates to study nonlinear many‐body physics and bosonic condensation, and in contrast to most inorganic systems, they allow the use at ambient conditions since they host ultra‐stable Frenkel excitons. A well‐controlled, high‐quality optical lattice is implemented that accommodates light‐matter quasiparticles. The realized polariton graphene presents with excellent cavity quality factors, showing distinct signatures of Dirac cone and flatband dispersions as well as polariton lasing at room temperature. This is realized by filling coupled dielectric microcavities with the fluorescent protein mCherry. The emergence of a coherent polariton condensate at ambient conditions are demonstrated, taking advantage of coupling conditions as precise and controllable as in state‐of‐the‐art inorganic semiconductor‐based systems, without the limitations of e.g. lattice matching in epitaxial growth. This progress allows straightforward extension to more complex systems, such as the study of topological phenomena in 2D lattices including topological lasers and non‐Hermitian optics. [ABSTRACT FROM AUTHOR]

The passive safety in aircraft concerns all measures able to protect the passengers and crew in the event of an accident or emergency. In this context, an important role is played by the design adopted for components inside the passengers' cabin, such as the seats and the interior lining. An effective approach in design of passive safety system is provided by anthropomorphic test devices. In this work, a new design of the interior lining of the fuselage wall has been introduced and its crashworthiness features have been studied through a side impact of an unbelted window‐side passenger. The new proposed interior lining is made with a hybrid sandwich‐based design with a polypropylene honeycomb core able to ensure passive safety for passengers and thermal and acoustic insulation. [ABSTRACT FROM AUTHOR]

The integration of photonic microstructure into organic microcavities represents an effective strategy for manipulating eigenstates of cavity or polariton modes. However, well‐established fabrication processes for microstructured organic microcavities are still lacking. This study proposes a nanoimprint‐bonding process as a novel fabrication method for microstructured organic microcavities. This process relies on a UV nanoimprint technique utilizing two different photopolymer resins, enabling the independent fabrication of highly reflective reflectors and photonic microstructures without compromising the accuracy of each. The resulting organic microcavities demonstrate spatially localized photonic modes within dot structures and their nonlinear responses on the pumping fluence. Furthermore, a highly precise photonic band is confirmed within a honeycomb lattice structure, which is owing to the high quality factor of the cavity achievable with the nanoimprint‐bonding process. Additionally, a topological edge state is also observable within a zigzag lattice structure. These results highlight the significant potential of the fabrication method for advancing organic‐based photonic devices, including lasers and polariton devices. [ABSTRACT FROM AUTHOR]

We have prepared and characterized three coordination polymers formulated as [Dy2(C6O4Cl2)3(fma)6] ⋅ 4.5fma (1) and [Dy2(C6O4X2)3(fma)6] ⋅ 4fma ⋅ 2H2O with X=Br (2) and Cl (3), where fma=formamide and C6O4X22−=3,6‐disubstituted‐2,5‐dihydroxy‐1,4‐benzoquinone dianion with X=Cl (chloranilato) and Br (bromanilato). Compounds 1 and 3 are solvates obtained with slow and fast precipitation methods, respectively. Compounds 2 and 3 are isostructural and only differ in the X group of the anilato ligand. The three compounds present (6,3)‐gon two‐dimensional hexagonal honey‐comb structures. Magnetic measurements indicate that the three compounds show slow relaxation of the magnetization at low temperatures when a continuous magnetic field is applied, although with different relaxation times and energy barriers depending on X and the crystallisation molecules. Compounds 1–3 represent the first examples of anilato‐based lattices with formamide and field‐induced slow relaxation of the magnetization. [ABSTRACT FROM AUTHOR]

This article reports a carbon fiber–reinforced plastic Kagome composite honeycomb sandwich structure reinforced with polymethacrylimide (PMI) foam (PKCSS). Low‐velocity impact performances on the node, rib, and two cell centers of the PKCSS were experimentally compared with those on a composite Kagome honeycomb sandwich (CKHS), and the failure mechanism of the PKCSS was investigated. The impact process was analyzed through an explicit numerical analysis using ABAQUS. A three‐dimensional Hashin failure criterion was introduced using the VUMAT subroutine. Results confirmed that the PKCSS exhibits higher impact and specific loads than the CKHS, with the maximum improvements of 69.7% and 39.5%, respectively, under 50‐J impact energy. As an uncrushable material, the PMI foam provides strong impact resistance during its plateau stage. This technology of cell filling can be used to fabricate lightweight all‐composite honeycomb sandwiches for potential use in ultrahigh engineering applications. Highlights: Cell filling is applied in an all‐composite Kagome honeycomb sandwich.The LVI performances of the PKCSS and CKHS are experimentally compared.C‐scanning is used to analyze the failure of the considered structures.The PKCSS's numerical model is established to investigate the impact process.The enhancement mechanism of the PMI foam is analyzed. [ABSTRACT FROM AUTHOR]

Stereolithography has been used to create ceramic parts with complex geometry that is difficult to achieve with conventional fabrication techniques. This study used stereolithography to print silica honeycomb structures with a commercial Formlabs Form2 printer. The printed samples were sintered at different temperatures, and the print shape was retained up to 1300°C, but significant distortion from partial melting occurred at 1400°C. Higher sintering temperatures lead to more shrinkage, but it is non‐uniform among directions, with the open cell plane shrinking more than the dense plane of the sample. As expected, the density of samples also increases with the sintering temperature. At higher sintering temperatures, there is an increase in cristobalite and a decrease in quartz, tridymite, and amorphous silica. Regarding mechanical properties, the out‐of‐plane compressive strength is approximately one order of magnitude higher than the in‐plane compressive strength. When compressed along the out‐of‐plane direction, the samples sintered at lower temperatures surprisingly exhibit higher strength, which is explained by the micro‐cracking mechanism. As expected, the samples sintered at higher temperatures display higher strength when compressed along the in‐plane direction. [ABSTRACT FROM AUTHOR]

Nomex Honeycomb core is the foundational building block for manufacturing aerospace composite components. Its usage requires machining honeycomb in complex aerodynamic profiles where the quality of the core is governed by accuracy and precision of cut profiles. The assessment of accuracy and precision is directly related to forces induced in the cutting tool and cutting efficiency. These two parameters form the basis of a multi‐objective function that this paper aims to optimize for the milling operation. The parameter of depth of cut considered in this paper has not been analyzed in a multi‐objective optimization study of the Nomex Honeycomb core previously. A Taguchi‐based array of Design of Experiments followed by Analysis of Variance and correlation analysis is utilised. The results indicate that the most significant factor is the feed rate, with a percentage contribution of 72% for the cutting forces and depth of cut, with a percentage contribution of 85% in the case of cutting efficiency. The two parameters are optimized using Desirability Function Analysis and Grey Relational Analysis. The results are validated through experimental runs with an error within 5% of the statistical predictions, with the percentage improvement in cutting forces for optimum runs as compared to the worst experimental run at 47.8%. The percentage improvement in cutting efficiency likewise is 11%. [ABSTRACT FROM AUTHOR]

Triply periodic minimal surfaces (TPMS) and honeycomb structures are typical representatives of porous structures. In this paper, multi‐layer structures based on the combination of P‐surfaces and honeycomb structures are fabricated and the compression deformation characteristics are investigated based on quasi‐static compression tests and finite element simulation. The results show that the established finite element model can better simulate the deformation and damage modes of the multi‐layer structure, and the multi‐layer structure exhibits layer‐by‐layer deformation and sequential compression collapse in the deformation process. The tensile stress is crucial in the deformation and damage process of the P‐structure layer. The honeycomb structure layers show two different deformation modes: the inverted bell‐shaped "upward extrusion" and the bell‐shaped "downward extrusion." [ABSTRACT FROM AUTHOR]

The present research efforts are directed toward investigating dimensional stability, focusing on bio‐inspired periodic honeycomb lattice structures within carbon fiber reinforced glycol‐modified poly ethylene terephthalate (PETG) composites. These samples are fabricated using extrusion‐based 3D printing, with topological parameters such as shell thickness (ST), unit cell type (UCT), wall thickness (WT), unit cell orientation (UCO), skewing angle (SA), and unit cell size (UCS) being manipulated across three different levels. The experimental findings indicate that achieving the lowest dimensional length error is attainable under specific conditions, including a smaller ST of 0.5 mm, a square UCT, a WT of 0.5 mm, a UCO of 90°, a SA of 0°, and a UCS of 4 mm. Analyzing the results with ANOVA reveals that UCT (28.82%) and WT (18.73%) exert the most significant influence on the dimensional stability response. The regression model closely aligns with experimental outcomes, with an error percentage of 3%, rendering it suitable for large‐scale customization. Under the optimized topological parameters, carbon fiber‐reinforced PETG latticed composites exhibited a dimensional length error of 0.292 mm and a compressive strength of 21.56 MPa. Fractography analysis revealed a brittle mode of fracture across all samples, indicating their stiffness and strength, especially when compared to samples with lower wall thickness. These findings suggest that the designed carbon fiber‐reinforced PETG latticed composite material holds potential for use in minor surgical orthotic and prosthetic applications. Highlights: Bio‐inspired periodic honeycomb lattice structured PETG composites.Topological optimization on the dimensional properties.Taguchi optimization is performed on design‐based lattice structures.Unit cell type has highest contribution of 28.82% on dimensional properties. [ABSTRACT FROM AUTHOR]

The disposal of plastic foam, mostly composed of polystyrene, poses significant environmental challenges due to its high popularity, slow degradation, and low cost. To address this problem, recycling polystyrene foam waste (PF) has emerged as a promising solution to reduce plastic pollution. This paper presents a novel approach to mass‐produce highly ordered, porous honeycomb‐patterned film (hc‐film) using wasted PF as the raw material. The hc‐film is produced using an improved phase separation (IPS) method that utilizes methanol as a suitable pore inducer and template droplet stabilizer. Methanol provides the hc‐film with customizable features such as pore ordering, size, and separation. The freestanding hc‐film, achieved by adopting a water‐soluble polystyrene sulfonate as a scarified layer, can be transferred and utilized as a flexible mold to pattern various solid substrates with complicated surface morphologies using the pre‐impregnated technique. This study demonstrates the potential of this cost‐effective and efficient approach for various applications, such as super/anti‐wetting surfaces, microelectronics, optical devices, sensors, and nanogenerators. [ABSTRACT FROM AUTHOR]

Recent studies have revealed the potential of 2D moiré superlattices as a condensed matter quantum simulator. The realization of different lattice model Hamiltonians in moiré superlattices has become the focus of researches. Here, it shows that, compared to bilayer moiré superlattices where there is only one interface, the interference between moiré patterns at different interfaces in 2D multilayer structures allows the physical realization of more complicated lattice models. The concept is demonstrated by trilayer moiré superlattices (TMSLs) of MoS2, where it finds that isolated flat moiré bands appear near the valence band edge, and they can be described by the honeycomb lattice ionic Hubbard model. More importantly, the hopping strength, the on‐site Coulomb repulsion, and the staggered potential in the TMSLs are highly tunable through the control of the twist angle, the dielectric environment, and the perpendicular electric field. It is possible to achieve various transitions between distinct quantum phases in the TMSLs, spanning from weak to strong correlation regimes. Therefore, the proposed TMSLs can serve as a good platform to study the strong correlation physics in the honeycomb lattice ionic Hubbard model. [ABSTRACT FROM AUTHOR]

Materials properties are determined by their compositions and structures. In ABO3 oxides different cation orderings lead to mainly perovskite‐ or corundum like derivatives with exciting physical properties. Sometimes, a material can be stabilized in more than one structural modification, providing a unique opportunity to explore structure‐properties relationship. Here, CoVO3 obtained in both ilmenite‐(CoVO3‐I) and LiNbO3‐type (CoVO3‐II) polymorphs at moderate (8–12 GPa) and high pressures (22 GPa), respectively are presented. Their distinctive cation distributions affect drastically the magnetic properties as CoVO3‐II shows a cluster‐glass behavior while CoVO3‐I hosts a honeycomb zigzag magnetic structure in the cobalt network. First principles calculations show that the influence of vanadium is crucial for CoVO3‐I, although it is previously considered as non‐magnetic in a dimerized spin‐singlet state. Contrarily, CoVO3‐II shows two independent interpenetrating antiferromagnetic Co‐ and ferromagnetic V‐hcp sublattices, which intrinsically frustrate any possible magnetic order. CoVO3‐II is also remarkable as the first oxide crystallizing with the LiNbO3‐type structure where both metals contain free d electrons. CoVO3 polymorphs pinpoint therefore as well to a much broader phase field of high‐pressure A‐site Cobaltites. [ABSTRACT FROM AUTHOR]

Objective: To compare the detection rate and diagnostic accuracy of cardia polyps using endoscopy with blue laser imaging (BLI) and white‐light imaging (WLI). Methods: Patients were randomly divided into the BLI group and WLI group according to the endoscopic procedures. BLI followed by WLI was conducted in the BLI group, whereas WLI followed by BLI examination was conducted in the WLI group. The number, size, microstructure, and microvascular patterns of cardia polyps detected were recorded. Biopsy of the polyps was then performed. Results: The detection rate of cardia polyps in the BLI group was higher than that in the WLI group (7.87% vs 4.22%, P = 0.018). The rate of overlooked lesions in the BLI group was lower than in the WLI group (0.64% vs 3.38%, P = 0.003). The diagnostic coincidence rate between magnifying BLI and histopathology was 88.16%. The sensitivity, specificity, positive predictive value and negative predictive value for the diagnosis of neoplastic lesions by magnifying endoscopy with BLI were 90.91%, 87.69%, 55.56%, and 98.28%, respectively. The most remarkable patterns for predicting inflammatory polyps were the prolonged and fine network patterns (sensitivity 71.43%, specificity 93.75%). Small round combined with honeycomb patterns were the most common among fundic gland polyps (sensitivity 80.00%, specificity 98.48%). Neoplastic lesions presented as villous or ridge‐like combined with core vascular or unclear pattern for both microvascular and microstructure patterns. Conclusion: BLI is more effective than WLI in the detection and diagnosis of cardia polyps, and magnifying endoscopy with BLI may help diagnose such lesions. [ABSTRACT FROM AUTHOR]

3D printed honeycomb structures constituted by neat polylactic acid (PLA) and conductive PLA (PLAc) with different cell sizes and thicknesses were manufactured through 3D printing technology based on material extrusion (MEX). These structures were arranged into bi‐layer honeycomb structures (BHS) for evaluation of the microwave absorbing properties at the X‐band (8.2–12.4 GHz) and Ku‐band (12.4–18 GHz) frequency ranges. The effects of cell size, sample thickness, layer thickness ratio and the nature of the top layer on the electromagnetic attenuation performance of BHS samples were investigated in terms of reflection loss (RL). The components geometric characteristics and the arrangement of the layers exerted great influence on the RL values and effective absorption bandwidth (EAB). Overall the bilayer structures with 5 mm total thickness presented the best EM response in terms of EAB and minimum RL, where the component with the larger cell size (7.7 mm), PLAc (1 mm) as the top layer and PLA (4 mm) as the bottom layer exhibited the best results with RL values of −41 dB and EAB of 9.5 GHz. The BHS system with 7.7 mm cell size was more efficient in Ku band frequency range, whereas that with 3.5 mm cell size gave better response in the X‐band frequency range. Therefore, RL values and EAB can be adjustable by modifying the building strategy of the printed parts, such as thickness of the sample, cell size and thickness distribution of the conductive and non‐conductive layers. The findings in this work show the importance of the building strategy to fabricate components with controllable BHS and improved properties for microwave absorption application. [ABSTRACT FROM AUTHOR]

Inspired by rotating rigid structures, an auxiliary rotating triangular honeycomb structure (ARTH) is designed in this article. The structure has dual platform stress, which can reduce the initial peak stress generated during collisions, reducing injuries to pedestrians and vehicle occupants. The accuracy of the finite element numerical model is verified by experiments, and a series of researches are carried out. The mechanical properties of the structure at different velocities are studied and the classification diagram of deformation modes is obtained. Under low‐speed impact load, ARTH has two deformation stages and two stress plateau regions, in which the stress of the second plateau is more than twice that of the first plateau. Then, a theoretical model based on plastic dissipation theory predicts the stress platform at different deformation stages under quasi‐static conditions. Parametric analysis shows that increasing wall thickness t can significantly improve the stress platform and energy absorption, but the negative Poisson's ratio effect is weakened. The influence of angle θ on the first stage deformation of ARTH is significant. These studies can provide some references for the design of double‐platform stress and the reduction of initial peak stress of rotating auxiliary structures. [ABSTRACT FROM AUTHOR]

Consider the tight binding model of graphene, sharply terminated along an edge l parallel to a direction of translational symmetry of the underlying period lattice. We classify such edges l into those of "zigzag type" and those of "armchair type", generalizing the classical zigzag and armchair edges. We prove that zero energy / flat band edge states arise for edges of zigzag type, but never for those of armchair type. We exhibit explicit formulas for flat band edge states when they exist. We produce strong evidence for the existence of dispersive (non flat) edge state curves of nonzero energy for most l. [ABSTRACT FROM AUTHOR]

A multi‐edge micro‐tooth longitudinal‐torsional ultrasonic‐assisted milling (LTUAM) model was established based on the hard brittle characteristics of carbon fiber honeycomb composites and the weak strength characteristics of the hole wall interface. The study analyzed the effects of ultrasonic characterization parameters on the cutting force, honeycomb wall width, and surface morphology. The results indicate that using LTUAM significantly reduced the cutting force and decreased the length and height of the burrs at an appropriate ultrasound amplitude. The spindle speed had the least impact on the width of the honeycomb wall, but increased with the longitudinal‐torsional ultrasonic amplitude and feed rate. The maximum error between the simulated and experimental cutting force values was approximately 19%. The longitudinal amplitude and torsional amplitude were 3 and 5 μm, respectively, the length of burrs decreased by 52.7%, and there was less delamination and tearing damage. LTUAM proved to be beneficial in improving cutting performance. Compared with conventional milling (CM), LTUAM resulted in regular fiber fracture morphology and smaller fragments on the honeycomb surface. In addition, the high‐frequency ultrasonic vibration promoted carbon fiber fracture and the surface roughness value under LTUAM was approximately 36.72% smaller than that of CM. Highlights: Ultrasonic milling mechanism of carbon honeycomb is studied.Kinematic simulation of the tool of carbon honeycomb was studied during LTUAM.LTUAM promotes the fracture of carbon fibers.A multi‐edge micro‐tooth LTUAM model was established of carbon honeycomb.Deformation of the cell wall can be avoided by ultrasonic vibration of the cutter. [ABSTRACT FROM AUTHOR]

The construction of effective conductive networks can enhance the electromagnetic interference (EMI) shielding performance of the conductive polymer composites (CPCs). Herein, poly (l‐lactide) (PLLA) micro‐particles were used as a volume‐occupying phase to design and prepare the PLLA/polydimethylsiloxane/multi‐walled carbon nanotubes (PLLA/PDMS/MWCNT) composites with honeycomb‐like conductive networks. The interfacial morphology of the composites was adjusted by changing the surface morphology of the PLLA micro‐particles. The effects of the morphology and particle size of the PLLA phase on the EMI shielding effectiveness (SE) of the composites were investigated in this study. The results indicate that the PLLA micro‐particles with regular shape and rough surface can effectively improve the EMI shielding performance of the PLLA/PDMS/MWCNT composites with the same filler loadings and the particle size of PLLA micro‐particles. Specifically, the EMI SE of the composites with etched 300‐μm spherical micro‐particles with rough surface can achieve 35.1 dB, which is 15% higher than the EMI SE of 30.6 dB for the composites with the 300‐μm irregular micro‐particles. In addition, the R values of the composites with honeycomb‐like conductive networks are below 0.5, indicating absorption dominated shielding mechanism. Highlights: Micro‐particle surface tunes the interfacial structure of the honeycomb‐like samples.Micro‐particles with different sizes endow different EMI SE for the composites.Samples with regular micro‐particles have higher EMI SE than irregular ones.The samples with etched micro‐particles have the highest EMI SE.The honeycomb‐like samples show an absorption‐dominated shielding mechanism. [ABSTRACT FROM AUTHOR]

Advances in electro‐ionic soft actuators hold significant potential as next‐generation bioelectronic interfaces due to mechanical compliance and operation in agreement with soft biological tissues and low voltages. However, current devices call for encapsulation strategies to accommodate high mechanical demands and long‐term stability in environmental changes. In this study, a durability of polyvinylidene‐fluoride‐co‐hexafluoropropylene (PVDF‐co‐HFP) honeycomb skeleton electrolyte encapsulated with a biocompatible polyisobutylene (PIB) thin film is being investigated. A low water vapor transmission rate (0.61 g m−2 day−1) and elastic modulus (10 kPa) are measured from a 7.5 µm‐thick thin‐modified PIB‐encapsulation layer. The PIB‐encapsulated soft actuator maintains 68% of its mechanical durability after 40 000 cycles of zero‐to‐tension fatigue loading at room temperature. A cantilever actuation test of the PIB‐encapsulated 3mm‐wide 30mm‐long actuator film shows a large tip displacement (15.90 mm) at a low voltage (±1.5 V) under 0.1 Hz, 37 °C, 50% relative humidity (RH). Most importantly, while the unencapsulated actuator immediately degrades in a few cycles at 37 °C, 50%RH, and 0.1% applied strain, PIB‐encapsulated soft actuator performs up to 6500 dynamic actuation cycles without any functionality degradation. Exceptional durability against mechanical fatigue and stability at elevated temperature and humidity meet the prerequisite for future soft biomedical robots that enable long‐lasting safe operations. [ABSTRACT FROM AUTHOR]

An efficient method for the synthesis of higher‐order iptycenes using an "ambident anthracene" building block is presented. For that purpose, an iterative elongation strategy involving the ring‐opening of an endoxide to give a highly reactive anthranoxide, followed by a Diels‐Alder reaction with an aryne was used. The method systematically provides higher‐order iptycenes, including trideciptycene, which is currently the iptycene with the longest chain to have been synthesized. X‐ray crystallography revealed interesting structures in which solvent molecules fill the cavities of these iptycenes, thus creating a "honeycomb" structure with the solvent molecules arranged in tubular spaces. [ABSTRACT FROM AUTHOR]

Quasiperiodic patterns and crystals—having long range order without translational symmetry—have fascinated researchers since their discovery. In this study, we report on new p‐terphenyl‐based T‐shaped facial polyphiles with two alkyl end chains and a glycerol‐based hydrogen‐bonded side group that self‐assemble into an aperiodic columnar liquid quasicrystal with 12‐fold symmetry and its periodic liquid‐crystalline approximants with complex superstructures. All represent honeycombs formed by the self‐assembly of the p‐terphenyls, dividing space into prismatic cells with polygonal cross‐sections. In the perspective of tiling patterns, the presence of unique trapezoidal tiles, consisting of three rigid sides formed by the p‐terphenyls and one shorter, incommensurate, and adjustable side by the alkyl end chains, plays a crucial role for these phases. A delicate temperature‐dependent balance between conformational, entropic and space‐filling effects determines the role of the alkyl chains, either as network nodes or trapezoid walls, thus resulting in the order‐disorder transitions associated with emergence of quasiperiodicity. In‐depth analysis suggests a change from a quasiperiodic tiling involving trapezoids to a modified one with a contribution of trapezoid pair fusion. This work paves the way for understanding quasiperiodicity emergence and develops fundamental concepts for its generation by chemical design of non‐spherical molecules, aggregates, and frameworks based on dynamic reticular chemistry. [ABSTRACT FROM AUTHOR]

This study reports the fabrication and characterization of molybdenum (Mo) metal and titanium‐zirconium‐molybdenum (TZM) alloy exoskeletons with honeycomb cavity structures (HCS) that are infiltrated with oxygen‐free high conductivity (OFHC) Cu under an inert atmosphere as a potential replacement for Cu‐Mo‐Cu laminate in heat sink applications for power electronics semiconductors like GaAs. The thermal expansion behavior and the thermal loading of the starting Mo and TZM structures, and of the Cu‐infiltrated parts are evaluated. The fabricated Mo and TZM structures with density >99% and Mo‐based heat sinks with improved CTE (6.6 × 10−6 K−1) when compared to conventional Cu‐Mo‐Cu laminated heat sinks (CTE = 7.6 × 10−6 K−1). The new Mo and TZM structures promise superior performance due to their closer CTE to that of GaAs and similar semiconductors (CTE = 5.7 × 10−6 K−1). Exposure to temperatures up to 1073 K did not affect the Mo microstructure due to the inherent resistance to recrystallization, while exposure to 1373 K did reduce hardness. In contrast, TZM exoskeletons showed resistance to recrystallization even at 1373 K. The fabricated composite heat sinks showed thermal diffusivity (≈61 × 106 m2 s−1) that is within the upper limits of those reported for commercial laminated heat sinks (45 to 65 × 106 m2 s−1). [ABSTRACT FROM AUTHOR]

Honeycomb composite with excellent mechanical–physical properties had attracted extensive attention. To achieve outstanding sound insulation while maximizing the high‐performance of honeycomb composite, this article reported a honeycomb composite structure filled with glass fiber (HFG) based on a paper‐making process and the corresponding sandwich structure. Pulping parameters, mechanical property, air permeability and sound insulation of HFG were analyzed. The results showed that the hanging index and settling height of glass fiber slurry were inversely proportional to the beating degree, which was beneficial for reducing the coefficient of variation (CV) of HFG with value of 4%–6%. The maximum improvement in tensile strength and bursting strength of HFG were 70% and 53%, respectively. In addition, sound transmission loss (STL) of HFG was proportional to cell size, density, filling amount and thickness of the honeycomb. Compared to HFG, sandwich structure consisting of HFG and glass fiber/hot melt fiber panels effectively improved STL, especially at low‐mid frequencies. It was also found that designing holes on the surface of sandwich structure could further improve STL in certain frequency bands. The structure offered a lightweight and high‐performance response for construction, transportation and infrastructure. Highlights: This article designs a new type of honeycomb filled glass fiber via paper‐making process, aiming to improve the comprehensive performance of honeycomb.By the design of embedded structure, the maximum improvement in tensile strength and bursting strength of honeycomb were 70% and 53%, respectively.By designing perforated, embedded and laminated structures, sound insulation has been improved, while reducing material quality. [ABSTRACT FROM AUTHOR]

To realize the one‐dimensional deformation of morphing wings, zero Poisson's ratio (ZPR) honeycomb metamaterials have become a popular research topic due to their lightweight, low in‐plane modulus, and high out‐of‐plane strength. A ZPR honeycomb metamaterial is designed and prepared from short‐cut carbon fiber‐reinforced polyetheretherketone (CF/PEEK) by a 3D printer. The mechanical properties of ZPR honeycomb metamaterials were tested to determine their tensile and bending stiffness. The results show that the metamaterial can achieve 62.3% ± 3.3% in‐plane elastic deformation after optimized structure design. At the same time, metamaterial has a certain bending resistance to keep the airfoil from normal buckling deformation. Moreover, a new test method for evaluating the cycle deformation behavior of flexible morphing wings is proposed. The high‐speed cyclic tension‐compression test showed that H22‐t0.6‐CT has the best stability, which may be related to its lower porosity (2.15% ± 0.12%). These results indicate that ZPR honeycomb metamaterials have great application prospects in the field of morphing wings. Highlights: The printed CF/PEEK wire is treated as a transversely isotropic material.ZPR honeycomb metamaterial allows for more than 50% in‐plane deformation.A new test method to evaluate the cyclic deformation behavior. [ABSTRACT FROM AUTHOR]

Complex structural configuration design is necessary for dielectric‐magnetic lossy composites to achieved broadband microwave absorption in civil and defense applications. Based on the unique space filling characteristic of fractal structure, the honeycomb metastructure can possess microwave absorption and mechanical resistance. However, traditional molding technique was difficult to realize complex shape of metastructure. Herein, the dielectric‐magnetic filament with different concentration of carbonyl iron particles was fabricated by high‐temperature extrusion process. The multi‐physical honeycomb metastructure with gradient layers was printed by fused deposition modeling (FDM) in a large size. The printed dielectric‐magnetic samples exhibited strong dielectric‐magnetic loss with high printing quality. The honeycomb metastructure achieved broadband microwave absorption in the −10 dB bandwidth of 9.6–18 GHz with tensile strength of 31 MPa. The results indicate that FDM is useful to fabricate metastructure with complex shape for broadband microwave absorption. The dielectric‐magnetic properties of filament are magnified by metastructure design. The proposed design‐fabrication process is promising for functional structure realization with complex shape in the future. Highlights: 1. Magnetic filament was fabricated for functional 3D printing. 2. Structural magnetic dissipation mechanism for microwave was presented. 3. Magnetic metastructure was designed and printed for broadband absorption. 4. Integrated design of mechanical and electromagnetic function was presented. 5. Structural absorption effect of honeycomb metastructure was revealed. [ABSTRACT FROM AUTHOR]

In this article, the non‐linear free vibration behavior of sandwich composite panels with sinusoidal corrugations is examined. These panels consist of a top and bottom skin made of a graphene‐reinforced composite, with an auxetic honeycomb core having negative Poisson's ratio. The non‐linear kinematic field is based on Kant's higher‐order shear‐deformation theory and the Green‐strain, which incorporates all the higher‐order terms. By implementing the Hamilton principle, the non‐linear governing equations are affirmed and solved further through 2D‐isoparametric finite element approximations via Lagrangian elements in conjunction with Picard's successive iterative scheme. The comparison and validation tests demonstrate the correctness of the present model. The established sandwich model is further employed for various parametric conditions by varying the core‐to‐face sheet thickness, auxetic honeycomb properties, graphene volume fraction, shell configurations, temperature, and support conditions. These numerous results exemplify the non‐linear frequencies at small‐to‐large amplitudes for the sandwich shell structures and are discussed in detail. In addition, a multi‐objective parametric optimization is conducted using the response surface method to investigate the optimal values of the corrugated auxetic honeycomb shell panel's parameters, resulting maximum frequency. Highlights: Non‐linear vibration of corrugated sandwich shell panel.Graphene reinforced skins and honeycomb auxetic core.Kant's higher‐order shear‐deformation theory and Green‐Lagrange non‐linearity.Hamilton principle and Picard's successive iterative scheme.Multi‐objective parametric optimization and prediction using response surface methodology. [ABSTRACT FROM AUTHOR]