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Herein, an improved mechanical metamaterial is proposed, which is derived from the decomposition, rotation, and reassembly of reentrant structures. The structure is parametric, allowing for rapid redesign. The study focuses on the variations in equivalent stiffness and Poisson's ratio of the structure within the linear elastic range when internal rib angle θ changes. First, based on homogenization simulation analyses, it has been verified that this design achieves the tailorable equivalent elastic modulus and Poisson's ratio over a wide range, meanwhile, maintaining equal elastic properties in the orthogonal direction at all times. Second, to reduce future repetitive experiments, an interpolation model is established to expand the design domain. The fitting formula indicates that by modifying θ and relative wall thickness t/L0, the elastic performance of the structures can be tailored. Additionally, the impact of boundary conditions is discussed to minimize experimental costs. Finally, the accuracy of the simulations is validated through uniaxial compression tests. [ABSTRACT FROM AUTHOR]

Incorporating arc‐curved configuration into auxetic honeycomb can evenly distribute pressure, reduce stress concentration, and avoid fracture. In this work, a novel arc‐curved chiral star‐shaped honeycomb (ACSH) has been proposed by combining the chiral honeycomb (CH), the star‐shaped honeycomb (SSH), and arc‐curved configurations. The crushing response of the ACSH is studied experimentally and numerically. In order to verify the accuracy of simulation, quasi‐static compression experiment is carried out on the ACSH sample fabricated by 3D printing. Subsequently, the crashworthiness of the ACSH is compared with other honeycombs. Particularly, under the crushing velocity of 2 m s−1, the ACSH exhibits exceptional specific energy absorption, which is 179% higher than that of the conventional SSH. Additionally, it is also found that introducing arc‐curved configuration can effectively reduce initial peak stress. Moreover, the effect of functionally graded design on crashworthiness is systematically analyzed. The findings indicate that the initial peak stress decreases with the decrease of gradient rate. When crushing velocity increases to 80 m s−1, the SEA of the ACSH increases with the increase of gradient rate. This work investigates the crushing response of a novel honeycomb, which can provide a reference for designing and optimizing novel lightweight honeycombs with better crashworthiness. [ABSTRACT FROM AUTHOR]

Magnetosheath jets with enhanced dynamic pressure are common in the Earth's magnetosheath. They can impact the magnetopause, causing deformation of the magnetopause. Here we investigate the 3‐D structure of magnetosheath jets using a realistic‐scale, 3‐D global hybrid simulation. The magnetosheath has an overall honeycomb‐like 3‐D structure, where the magnetosheath jets with increased dynamic pressure surround the regions of decreased dynamic pressure resembling honeycomb cells. The magnetosheath jets downstream of the bow shock region with θBn ≲ 20° (where θBn is the angle between the upstream magnetic field and the shock normal) propagate approximately along the normal direction of the magnetopause, while those downstream of the bow shock region with θBn ≳ 20° propagate almost tangential to the magnetopause. Therefore, some magnetosheath jets formed at the quasi‐parallel shock region can propagate to the magnetosheath downstream of the quasi‐perpendicular shock region. Plain Language Summary: Magnetosheath jets are high‐speed transient structures frequently observed in the magnetosheath, and they can impact and dent the magnetopause. However, their three‐dimensional (3‐D) structure is still under debt despite decade‐long research. By performing high‐resolution, 3‐D numerical simulation, we reveal that the magnetosheath has an overall honeycomb‐like 3‐D structure where the jets surround regions with lower plasma velocity resembling honeycomb cells. Key Points: Magnetosheath jets are studied by a realistic‐scale, 3‐D global hybrid simulation under a radial interplanetary magnetic field (IMF)The magnetosheath has a honeycomb‐like 3D structure where regions of increased dynamic pressure surround those of decreased dynamic pressureThe magnetosheath jets formed at the quasi‐parallel shock can propagate to the magnetosheath downstream of the quasi‐perpendicular shock [ABSTRACT FROM AUTHOR]

In recent years, communication systems, including RFID, have been used in intelligent beehives for beekeeping. RFID systems in the UHF frequency band offer reading distances of tens of centimetres, allowing the localisation and identification of the queen bee inside the hive. With this purpose, this work proposes an analysis of an environment of propagation that consists of a honeycomb frame, where the reader is placed within the frame, and the tag is placed in different positions over it. A honeycomb frame consists of a wooden box containing a honey wax panel, supported by metallic wires. The environment is modelled theoretically using its S-parameters and simulated in CST Studio. An analysis of these results and empirical measurements is performed. The results show that a periodicity in the received power of the tag is found with respect to the distance to the reader when the tag is located in a direction parallel to the wire, where local maximum and minimum values are found. Additionally, when the tag is placed over a wire of the frame, a higher received power is obtained compared to the case where the tag is placed between two wires. Furthermore, it has been observed that the reading range has increased with respect to free space, covering the full frame. [ABSTRACT FROM AUTHOR]

Two main goals are pursued in the present work. First, the global buckling of axially loaded sandwich beams with composite face sheets and aluminum honeycomb cores under humid environments is investigated. An analytical solution with high accuracy is developed based on piecewise low-order shear deformation theory (PLSDT) to estimate the critical buckling loads. A parametric study is carried out to examine the influence of geometric parameters on the buckling loads of simply supported and clamped sandwich beams under different wet conditions. The obtained results indicate that humidity plays a significant role in the buckling behavior of honeycomb sandwich beams. As the second purpose of the present work, the weight minimization of sandwich beams is studied. The optimization variables include the face sheet thickness, core thickness, honeycomb cell size and honeycomb cell wall thickness. Moreover, different failure modes, including global buckling, face sheet dimpling, face sheet wrinkling, core shear instability, and face sheet failure are considered as design constraints. Imperialist competitive algorithm (ICA), a powerful socio-politically motivated global search strategy, is applied to handle the constrained optimization problem. The optimization results show that the presence of humidity in the environment significantly changes the optimal design of sandwich beams and makes them heavier. Furthermore, it is observed that by increasing the length of the structure, the optimal design is more affected by humidity. Moreover, it is found that ICA is a very powerful optimization tool both in obtaining the best values of geometric parameters and in reducing the computational cost. [ABSTRACT FROM AUTHOR]

An innovative multi-layer composite explosion containment vessel (CECV) utilizing a sliding steel plate-aluminum honeycomb-fiber cloth sandwich is put forward to improve the anti-explosion capacity of a conventional single-layer explosion containment vessel (SECV). Firstly, a series of experiments and finite element (FE) simulations of internal explosions are implemented to understand the basic anti-explosion characteristics of a SECV and the rationality of the computational models and methods is verified by the comparison between the experimental results and simulation results. Based on this, the CECV is designed in detail and a variety of FE simulations are carried out to investigate effects of the sandwich structure, the explosive quantity and the laying mode of the fiber cloth on anti-explosion performance and dynamic response of the CECV under internal explosions. Simulation results indicate that the end cover is the critical position for both the SECV and CECV. The maximum pressure of the explosion shock wave and the maximum strain of the CECV can be extremely declined compared to those of the SECV. As a result, the explosive quantity the CECV can sustain is up to 20 times of that the SECV can sustain. Besides, as the explosive quantity increases, the internal pressure of the CECV keeps growing and the plastic deformation and failure of the sandwich structure become more and more severe, yielding plastic strain of the CECV in addition to elastic strain. The results also reveal that the laying angles of the fiber cloth's five layers have an impact on the anti-explosion performance of the CECV. For example, the CECV with fiber cloth layered in 0(/45(/90(/45(/0( mode has the optimal anti-capacity, compared to 0(/0(/0(/0(/ 0( and 0(/30(/60(/30(/0( modes. Overall, owing to remarkable anti-explosion capacity, this CECV can be regarded as a promising candidate for explosion resistance. [ABSTRACT FROM AUTHOR]

The rapid development of additive manufacturing (AM) has facilitated the creation of bionic lightweight, energy-absorbing structures, enabling the implementation of more sophisticated internal structural designs. For protective structures, the utilization of artificially controlled deformation patterns can effectively reduce uncertainties arising from random structural damage and enhance deformation stability. This paper proposed a bionic corrugated lightweight honeycomb structure with controllable deformation. The force on the onset state of deformation of the overall structure was investigated, and the possibility of controlled deformation in the homogeneous structure was compared with that in the corrugated structure. The corrugated structures exhibited a second load-bearing capacity wave peak, with the load-bearing capacity reaching 60.7% to 117.29% of the first load-bearing peak. The damage morphology of the corrugated structure still maintained relative integrity. In terms of energy absorption capacity, the corrugated lightweight structure has a much stronger energy absorption capacity than the homogeneous structure due to the second peak of the load carrying capacity. The findings of this study suggested that the combination of geometric customization and longitudinal corrugation through additive manufacturing offers a promising approach for the development of high-performance energy-absorbing structures. [ABSTRACT FROM AUTHOR]

We extracted pollen from historical honeycomb specimens of beeswax to highlight the potential of beeswax as a source for palynological studies. The pollen composition was explored as a proxy for honeybee foraging in the past. Additionally, we wanted to illuminate the potential of the palynological analysis to provenance the specimens. Danish honeycomb samples from the Natural History Museum of Denmark, dating from the late 19th, early twentieth century were processed and analysed for pollen identification. We used Ellenberg values to represent functional traits for the identified taxa and applied these as explanatory variables to study the variation in foraging environment and plant preference of the honeybees. Our results indicate variations of an agricultural landscape, with bees foraging on plants that are high in nutritional value. We found that information gained from palynological analysis of museum samples may be useful in illuminating details of historical apiology. We present our study in light of the importance of environmental biodiversity in Denmark and its vitality for bees as key pollinators in our ecosystem. [ABSTRACT FROM AUTHOR]

A modified 3D re-entrant honeycomb is designed and fabricated utilizing Laser Cladding Deposition (LCD) technology, the mechanical properties of which are systematically investigated by experimental and finite element (FE) methods. Firstly, the influences of honeycomb angle on localized deformation and the response of force are studied by an experiment. Experimental results reveal that the honeycomb angles have a significant effect on deformation and force. Secondly, a series of numerical studies are conducted to analyze stress characteristics and energy absorption under different angles (α) and velocities (v). It is evident that two variables play an important role in stress and energy. Thirdly, response surface methodology (RSM) and the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) are implemented with high precision to solve multi-objective optimization. Finally, the final compromise solution is determined based on the fitness function, with an angle of 49.23° and an impact velocity of 16.40 m/s. Through simulation verification, the errors of energy absorption (EA) and peak crush stress (PCS) are 9.26% and 0.4%, respectively. The findings of this study offer valuable design guidance for selecting the optimal design parameters under the same mass conditions to effectively enhance the performance of the honeycomb. [ABSTRACT FROM AUTHOR]

Reduced order models facilitate initial design space investigations and enable assessing the benefits of compliant structures utilized for shape adaptability. This work presents a simple model to determine the flexural rigidity of a beam-like, multistable metastructure used as a spar in a hybrid spanwise morphing wing. The model considers the more complex metabeam as a homogeneous beam described by Euler-Bernoulli beam theory with an equivalent flexural rigidity. The analytical model's validity is established by comparing the obtained static and dynamic responses to finite element simulations. A closed-form expression of the flexural rigidity is then given, drawing from the multistable honeycomb’s material properties and the metabeam’s geometry. The model’s limitations are addressed by examining several specific cases of the metabeam’s morphed configurations and a more complex metabeam structure. [ABSTRACT FROM AUTHOR]

The study of topological indices prompted mathematicians to venture into mathematical chemistry, specifically chemical graph theory. They are quantitative measures that reflect the topology of the molecular graph of a compound, without taking into account of any information about the chemical bonds or the atom positions. Graphene is a monolayer carbon allotrope that is tightly bound in a hexagonal honeycomb lattice. It is an eco-friendly compound and a sustainable solution for almost countless applications. In this paper, we estimate three neighborhood number-based topological indices; Mostar index, PI index and Szeged index of Graphene structure, considering all possible cases in the number of rows and hexagons. The results are obtained and corresponding graphs are plotted along with the contour plot. [ABSTRACT FROM AUTHOR]

Downhole drilling tool vibration measurement is crucial for drilling exploration safety, so real-time monitoring of vibration data is required. In this research, a honeycomb triboelectric nanogenerator (H-TENG) capable of adapting to various downhole environments is proposed. It can measure the frequency of downhole drilling equipment's vibrations and transfer mechanical energy to electrical energy for use in powering other low power downhole meters. In order to preliminarily verify the possibility of sensors used for vibration measurement of downhole drilling tools, we built a simulated vibration platform to test the sensing performance and vibration energy collection performance of H-TENG. According to the testing results, the measurement range of vibration frequency and amplitude are 0 to 11 Hz and 5 to 25 mm, respectively, and the corresponding measurement errors are less than 5% and 6%, respectively. For vibrational energy harvesting, when four sensors are wired in series with a 107 resistance, the maximum power is approximately 1.57 μW. Compared to typical methods for measuring downhole vibration, the honeycomb triboelectric nanogenerator does not need an external power source, it has greater reliability and output power, and it can vary its shape to adapt to the complicated downhole environment. In addition, the H-TENG can be combined freely according to the diameter of the drill string, and even if one sensor unit is damaged, the other units can still be used normally. [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]

In contrast to short helical peptides, constrained peptides, and foldamers, the design and fabrication of crystalline 3D frameworks from the β-sheet peptides are rare because of their high self-aggregation propensity to form 1D architectures. Herein, we demonstrate the formation of a 3D porous honeycomb framework through the silver coordination of a minimal β-sheet forming a peptide having terminal metal coordinated 4- and 3-pyridyl ligands. [ABSTRACT FROM AUTHOR]

Two-dimensional aperiodic lattices emerge as remarkably isotropic metamaterials with potentially unconventional mechanical behavior. This study investigates numerically estimating the effective elastic properties, as a function of relative density, of novel two-dimensional aperiodic lattice metamaterials derived from the recently discovered aperiodic monotiles, known as the “Hat,” “Turtle,” and “Spectre” tiles. Furthermore, several classes of the Hat-based lattices; namely Hexagon (H), Triangle (T), Parallelogram (P), and Fan (F), are also investigated. The results show that these aperiodic lattices have isotropic elastic properties independent of relative density. The Hat-based and Turtle lattices exhibit larger elastic moduli, gradually converging to the Spectre-based lattices as relative density increases. A distinctive feature of the Hat-based lattices is their directional auxetic behaviour with an anisotropic Poisson’s ratio, whereas the Turtle lattices show an auxetic behaviour only at lower relative densities. Despite anisotropic Poisson’s ratios, the current aperiodic lattices maintain elastic isotropy, offering a unique blend of anisotropic auxetic behavior and isotropic elastic moduli. This study contributes to a better understanding of the elastic properties of aperiodic monotile lattice metamaterials and their potential for engineering their mechanical behavior for certain applications.

A method for measuring the resistive characteristics of channels in the blanks of microchannel plates was developed. Two probes were used for measurements, which minimized leakage currents through adjacent channels. The resistive properties of single channels of the microchannel insert in the reduced blank of MCP 18-10 were studied. It was established that the resistance of the channels depends on their position in the microchannel honeycomb. It was shown that the channels located in close proximity to the monolithic frame have less resistance compared to those located in the middle of a multicore glass honeycomb. [ABSTRACT FROM AUTHOR]

With rapid progress in simulation of strongly interacting quantum Hamiltonians, the challenge in characterizing unknown phases becomes a bottleneck for scientific progress. We demonstrate that a Quantum-Classical hybrid approach (QuCl) of mining sampled projective snapshots with interpretable classical machine learning can unveil signatures of seemingly featureless quantum states. The Kitaev-Heisenberg model on a honeycomb lattice under external magnetic field presents an ideal system to test QuCl, where simulations have found an intermediate gapless phase (IGP) sandwiched between known phases, launching a debate over its elusive nature. We use the correlator convolutional neural network, trained on labeled projective snapshots, in conjunction with regularization path analysis to identify signatures of phases. We show that QuCl reproduces known features of established phases. Significantly, we also identify a signature of the IGP in the spin channel perpendicular to the field direction, which we interpret as a signature of Friedel oscillations of gapless spinons forming a Fermi surface. Our predictions can guide future experimental searches for spin liquids. Characterizing quantum phases realized in simulation can be difficult, such as the re-entrant gapless phase of the Kitaev model induced by a magnetic field. Employing a quantum-classical hybrid approach that involves mining projective snapshots with interpretable classical machine learning, the authors uncovered Friedel oscillations of a spinon Fermi surface, providing support for a gapless quantum spin liquid. [ABSTRACT FROM AUTHOR]

A novel re-entrant honeycomb metamaterial based on 3D-printing technology is proposed by introducing chiral structures into diamond honeycomb metamaterial (DHM), named chiral-diamond-combined honeycomb metamaterial (CDCHM), and has been further optimized using the assembly idea. Compared with the traditional DHM, the CDCHM has better performance in static and vibration isolation. The static and vibration properties of the DHM and CDCHM are investigated by experiments and simulations. The results show that the CDCHM has a higher load-carrying capacity than that of the DHM. In addition, the vibration isolation optimal design schemes of the DHM and CDCHM are examined by experiments and simulations. It is found that the vibration suppression of the CDCHM is also improved greatly. In particular, the optimization approach with metal pins and particle damping achieves a wider bandgap in the low-frequency region, which can strengthen the suppression of low-frequency vibrations. And the introduction of particle damping can not only design the frequency of the bandgap via the alteration of the dosage, but also enhance the damping of the main structure. This work presents a new design idea for metamaterials, which provides a reference for the collaborative design of the static and vibration properties of composite metamaterials. [ABSTRACT FROM AUTHOR]

The design of graded and multifunctional lattice cores is driven by the increasing demand for high-performance components in lightweight engineering. This trend benefits from significant achievements in additive manufacturing, where the lattice core and the face sheets are fabricated simultaneously in a single print job. This work systematically compares the mechanical performance of sandwich panels comprising various graded lattice cores subjected to concentrated loads. In addition to graded lattice cores, uniform lattices and conventional honeycomb cores are analyzed. To obtain an optimized graded lattice core, a fully stressed design method is applied. Stresses and displacements are determined using a linear elastic analytical model that allows grading the core properties in a layerwise manner through the core thickness. The analysis indicates the superior performance of graded lattice cores compared to homogeneous lattice cores. However, conventional honeycombs outperform graded lattice cores in terms of load-to-weight ratio and stiffness-to-weight ratio. This study provides valuable insights for the design of lattice core sandwich panels and the advantages of several design approaches. [ABSTRACT FROM AUTHOR]

This paper proposed a new structural design method for multi-layer honeycomb-filled woven fabrics, and the impact resistance of rope-like core supporting fabrics was studied on multi-layer honeycomb woven fabrics. The effects of the rope-like core filling yarn fineness, the rope-like core surface structure and the multi-layer fabric surface structure on the impact resistance of the filled fabric were analyzed. Nine samples were woven with different factors in accordance with the orthogonal test scheme. The effects of the above factors on the peak transmitted force of the filled fabric were discussed. The study demonstrates that all three factors are significant, and the primary order of influence with the optimal level in the parentheses is rope-like core filling yarn fineness ( 22.22 tex) > multi-layer fabric surface structure ( interweave 2/2 ) > rope-like core surface structure (interweave 3/1). [ABSTRACT FROM AUTHOR]

The cuttlebone is known for its ability to possess high specific stiffness, progressive failure and lightweight from the porous chambered structure. Inspired by the microstructural characteristics of cuttlebone and incorporating the wall gradient design, a series of double-asymmetric honeycombs were designed and processed by LPBF. Results indicated that bionic structural units with the junction design can maintain the integrity of the residual parts after local buckling and failure, improving the load-bearing capacity. The double-asymmetric honeycomb with gradation parameter a = 2/3 achieved a maximum specific compressive strength of 70.64 MPa cm3/g. As a decreases, there is an increase in specific energy absorption and a narrowing of the hysteresis loop. The as-build honeycomb had undergone stress-induced martensite transformation during compression. The dissipated mechanical energy (ME) decreased with the increasing cycle number and the decreasing a. The results provide design guidelines and process strategies for developing high-performance honeycombs. [ABSTRACT FROM AUTHOR]

Experimental observations show that the zero-field ground state of honeycomb-layered cobaltates is an incommensurate spiral order with an ordering wave vector along the Γ→ Mline. However, in the presence of a magnetic field, the incommensurate magnetic phase becomes unstable and the quantum spin liquid phase becomes stable in this class of materials. Here, the central question we address is how to realize the incommensurate order theoretically. For this purpose, we are interested in studying the generalized Kitaev-Heisbenerg model and investigating the interplay effect between conventional Heisenberg and bond-dependent exchange interactions on the stability of the incommensurate spiral order. Our results show that the interplay between the second neighbor Heisenberg interaction and bond-dependent exchange interactions play a vital role in the stability of incommensurate phases. The competition between the second nearest nearest-neighbor interaction and the off-diagonal bond-directional exchange for BaCo2(AsO4)2 may place this material in proximity to a quantum spin liquid phase. The quantum spin liquid can be accessible for BaCo2(AsO4)2 in the presence of an external magnetic field. [ABSTRACT FROM AUTHOR]

In graph theory, a commonly used concept is the partition dimension or partition metric basis is to uniquely identify the node set of a structure by dividing it into smaller subsets, known as partition resolving sets. These subsets can then be used to define the partition dimension or partition metric of the graph. This concept is useful in the analysis and understanding of the structure and properties of graphs. This article describes a partition dimension of the line graph of the honeycomb network, the Aztec diamond network, and the extended Aztec diamond network. [ABSTRACT FROM AUTHOR]

In the Van der Waals material NiPS 3 , Ni atoms have spin S = 1 and realize a honeycomb lattice. Six sulfur atoms surround each Ni and split their d manifold into three filled and two unfilled bands. Aimed to determine the spin Hamiltonian of NiPS 3 , we study its exchange mechanisms using a two-band half-filled Hubbard model. Hopping between d-orbitals is mediated by p orbitals of sulfur and gives rise to bilinear and biquadratic spin couplings in the limit of strong electronic correlations. The microscopic model exposed a ferromagnetic biquadratic spin interaction K 1 , allowing the completion of a minimal J 1 − J 3 − K 1 spin Hamiltonian for NiPS 3 . In bulk, a ferromagnetic first nearest neighbor J 1 and a more significant antiferromagnetic third nearest neighbor spin coupling J 3 agreed with the literature, while in monolayer, J 1 is positive and very small in comparison. Using a variational scheme, we found that a zig–zag antiferromagnetic order is the ground state of bulk samples. The zig–zag pattern is adjacent to commensurate and incommensurate spin spirals, which could hint at the puzzling results reported in NiPS 3 monolayers. [ABSTRACT FROM AUTHOR]

The nonlinear static and vibration response of micro composite sandwich plate with honeycomb core have been investigated in this paper. The displacement–strain of skins via higher-order shear deformation theory (HSDT) is obtained. In frame work Halpin–Tsai model the composites plate with two layers of Graphene platelet reinforcement (GPLRC) with uniform distribution pattern and a hexagonal honeycomb core is considered. The governing equations of sandwich plate are derived by implementing Hamilton's principle and solved Perturbation method. For investigating the accuracy, this paper is validated with other previous researches and a good correlation is observed between the results. Finally, the important findings of this research indicate that the ratio of core thickness, inclined angle, and thickness to inclined length have significant effects on nonlinear frequencies–amplitude and deflection response. Based on the results of this article designers can development of different parts of aircraft. [ABSTRACT FROM AUTHOR]

The conventional star-shaped honeycomb (CSSH) structure is inherently rich in mechanical properties. Based on the CSSH structure, the Poisson's ratio and Young's modulus can be improved by adding the tip re-entrant angle (ISSH). In this paper, a new concave four-arc honeycomb (CFAH) structure is proposed by designing the straight rod as a curved rod and retaining the tip re-entrant angle from the ISSH structure. The Young's modulus, specific stiffness and Poisson's ratio of CFAH structures are derived from Castigliano's second theorem and Moore's theorem. The theoretical results show good agreement with the numerical and experimental results. The results show that the normalized effective specific stiffness and normalized effective Young's modulus of the CFAH structure are further improved by about 12.95% and 16.86%, respectively, compared with the ISSH structure, and more significant auxiliary effects are obtained. CFAH structures show good promise in aerospace, construction and other applications due to their enhanced mechanical property. Meanwhile, the present work provides guidance for the study of concave four-arc honeycomb structures. [ABSTRACT FROM AUTHOR]

Navigating the crossroads of sustainable infrastructure and innovative waste management, this research unveils the potential of waste honeycombs (WHCs)—an overlooked byproduct of apiculture—as a potent modifier for asphalt binder formulations. This endeavor addresses the dual challenge of enhancing road pavement sustainability and mitigating environmental degradation. A meticulous methodology evaluated the impact of varying WHC concentrations (5, 10, and 15 wt.%) on the asphalt binder, examining its attributes pre- and post-aging. Employing an array of analytical tools—thin-layer chromatography-flame ionization detection (TLC-FID); Fourier transform-infrared spectroscopy (FT-IR); scanning electron microscopy (SEM); thermogravimetric analysis (TGA); and a suite of conventional tests such as penetration, softening point, viscosity, ductility, dynamic shear rheometer (DSR), and multiple stress-creep recovery (MSCR)—provided a comprehensive insight into the binder's behavior. TLC-FID analyses revealed that WHC, with its 92 wt.% resin content, altered the SARA profile across distinct aging conditions, notably reducing asphaltene content, a factor linked to binder stiffness. The colloidal instability index (IC) further attested to this, pointing to a more thermodynamically stable system with WHC's inclusion. Meanwhile, FT-IR confirmed a physical interaction between WHC and asphalt without introducing new chemical entities. SEM observations highlighted the superior miscibility of WHC with asphalt, evidenced by a unique microtexture. With marked precision, TGA assessments unveiled a bolstering of asphalt's inherent thermal resilience consequent to a minor WHC integration. From the conventional tests, shifts in penetration, softening point, and viscosity were observed, with reduced viscosity, indicating improved workability. Lastly, while rutting potential was sensitive to WHC concentrations, fatigue resistance notably heightened with minor to moderate WHC inclusions. In essence, this pioneering study advocates for WHC's integration into asphalt formulations, offering enhanced road performance coupled with sustainable waste utilization. The findings underscore the synergy between environmental stewardship and infrastructural advancement. [ABSTRACT FROM AUTHOR]

Two‐ and three‐periodic vertex‐transitive (isogonal) piecewise‐linear embeddings of self‐entangled and interwoven honeycomb nets are described. The infinite families with trigonal symmetry and edge transitivity (isotoxal) are particularly interesting as they have the Borromean property that no two nets are directly linked. These also lead directly to infinite families of interpenetrating primitive cubic nets (pcu) that are also vertex‐ and edge‐transitive and have embeddings with 90° angles between edges. [ABSTRACT FROM AUTHOR]

This study presents experimental results of compression after impact (CAI) testing of aluminum honeycomb core sandwich structure with face sheets made of co-cured T1100/3960 quasi-isotropic carbon/epoxy when tested at +22.5⁰ and −22.5⁰ with respect to the 0⁰ fibers. In a previous study examining the CAI strengths of honeycomb sandwich structure, it was found that specimens had different CAI strengths, based on a [−45/90/+45/0]S layup, depending on whether they were tested in the 0⁰ direction (face sheet layup of [−45/90/+45/0]S) or 90⁰ direction (face sheet layup of [+45/0/-45/90]S). The CAI strength results showed that the specimens tested in the 90⁰ direction had a 19% drop in CAI strength compared to specimens tested in the 0⁰ direction. This was attributed to the 0⁰ load bearing plies in the 0⁰ direction specimens being "tucked in" at the center of the specimen thus providing more stability against microbuckling. This raised the question as to what CAI strength would specimens tested at +22.5⁰ (face sheet layup of [−22.5/−67.5/+67.6/+22.5]S) and −22.5⁰ (face sheet layup of [−67.5/+67.5/+22.5/-22.5]S) have compared to specimens tested in the 0⁰ and 90⁰ direction. Results presented in this study show that the specimens loaded at +22.5⁰ and −22.5⁰ have a similar average CAI strength compared to the specimens loaded in the 0⁰ direction. The specimens loaded in the 90⁰ direction exhibit 16% lower average CAI strength. Additional specimens were tested in the +45⁰ direction to put the 0⁰ load bearing fibers on the outside of the specimen to see if this would decrease the strength as has been documented for undamaged strength. These specimens have average CAI strength values between the 0⁰ direction average CAI strength values and the 90⁰ direction average CAI strength values. [ABSTRACT FROM AUTHOR]

Beeswax is an important agricultural product in many developing countries and its quality can be affected by various factors of the harvesting and processing. This study compared the extraction yield as well as physicochemical properties of beeswax melted by different methods (solar energy and conventional method) and collected at different positions (surface of honeycomb and the old nest cakes). Obtained results showed that melting method mainly affected the recovery yield of beeswax and did not cause significant changes of chemical properties of products. However, samples collected at the surface of honeycomb seemed to have a higher quality in compared to samples collected from the old nest cakes. [ABSTRACT FROM AUTHOR]

Royal jelly production is a vital aspect of apiculture, yet achieving high yields while maintaining the health of bee colonies remains a challenge in industrial apiaries. This study addresses the need to enhance royal jelly production without compromising the production of other beekeeping products. The aim of this research was to compare the most effective technology for the formation of a nursery family for obtaining royal jelly in the field and to compare the queen cell acceptance by showing the type of material used in our experiment. The study outlines a comprehensive technology for obtaining royal jelly, encompassing key operations such as cup preparation, larval inoculation, colony preparation, jelly collection, and transportation. Emphasis is placed on the fundamental principles of royal jelly production in an industrial setting, with particular attention to stimulating queen cell formation and intensive larval rearing. Two variants of nursery family formation were investigated: one with complete orphanage and the other without orphanhood. The non-orphanhood method exhibited superior results, boasting a 33% larval adoption rate and 25% more mature queen cells compared to the complete orphanhood approach. Furthermore, this method yielded larger mother liquors and maintained colony productivity without interruption, addressing key concerns in royal jelly production. This study presents an innovative approach to royal jelly production that prioritizes both yield and colony health. The non-orphanhood method, coupled with the use of wax cups and silicone molds for larval transfer, offers a promising solution to enhance royal jelly production on an industrial scale, while preserving its biological value. [ABSTRACT FROM AUTHOR]

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This paper reports a new annular honeycomb that shows tunable Poisson's ratio. The presented honeycombs can provide both the in-plane negative Poisson's ratio (NPR) and in-plane zero Poisson's ratio (ZPR) while the shapes of the honeycomb core change. The developed honeycomb core is constructed by an annulus with four ligaments distributed bi-axial symmetrically, which shows great diversity of mechanical properties. The developed theoretical models of the in-plane elasticity are based on Castigliano's Second Theorem and energy principle. Two parameters were used to describe the deformation mechanisms of the unit cell concisely. The effect of two parameters on the Poisson's ratio and Young's modulus was investigated. The Young's modulus derived from the Finite Element (FE) analysis all have an good agreement with that derived from theoretical results, and the experiments were carried out to confirm the validity of them convincingly. [ABSTRACT FROM AUTHOR]

This work develops a novel design method for the actively deformable honeycomb structure to realize the variable thickness leading-edge wing. Firstly, the classical Gibson theory is extended to be applicable for the non-regular hexagonal honeycomb single-cell with the positive Poisson's ratio and the concave hexagonal honeycomb single-cell with the negative Poisson's ratio. The equivalent mechanical properties of the above two types of single-cells are deduced. Then, the concept of the deformation unit composed of positive and negative Poisson's ratio honeycomb multi-cells is proposed. The shape memory alloy is assigned as an actuator to produce the in-plane incompatible deformation which excites the out-of-plane bending of the deformation unit. The relationship between the in-plane driving displacement and the bending angle of the deformation unit is investigated. The segmented two-layered honeycomb-core plate composed of positive and negative Poisson's ratio honeycomb layers is constructed using deformation units. Finally, the initial configuration of the leading-edge is simulated by the segmented honeycomb-core plate. The driving displacements required to be imposed to each deformation unit are determined according to the target shape of the leading-edge. The proposed method is validated by changing the leading-edge from the blunt shape to the sharp shape, using finite element simulations. [ABSTRACT FROM AUTHOR]

We analyze propagation of quantum information along chiral Majorana edge states in two-dimensional topological materials. The use of edge states may facilitate the braiding operation, an important ingredient in topological quantum computations. For the edge of the Kitaev honeycomb model in a topological phase, we discuss how the edge states can participate in quantum-information processing, and consider a two-qubit logic gate between distant external qubits coupled to the edge. Here we analyze the influence of disorder and noise on properties of the edge states and quantum-gate fidelity. We find that realistically weak disorder does not prevent one from implementation of a high-fidelity operation via the edge. [ABSTRACT FROM AUTHOR]

Co3O4-based anodes are challenged by low rate capability and poor cycling stability, arising from the inherent structural instability of the electrode alongside difficulties for electrolyte penetration within the electrode interior. A potential solution to address this obstacle is through the meticulous design of electrode architecture. With this in mind, ultrathin nanosheets adorned with finely honeycomb-like Co3O4 porous balls featuring cavities were synthesized via in situ incorporation of a Co2+ source and SiO2 precursor solution. The Co3O4 porous balls, with a honeycomb-like structure, yielded a consistent discharge capacity of 727 mA h g−1 at 0.5 A g−1 over 230 cycles, and an impressive 540 mA h g−1 at 2 A g−1 over 500 cycles, indicative of remarkable rate capabilities. This exceptional electrochemical performance is credited to the distinctive porous honeycomb-like structure and cavities among the balls. This structure acts as a buffer against volume change during charge–discharge processes, guaranteeing a well-maintained electrode structure and providing strong cycling stability. Furthermore, these ultrathin and intricately porous nanosheets minimize the transport distance of ions and charges, facilitating access to more active sites. These notable features have the ability to augment rate performance and lithium storage capabilities. [ABSTRACT FROM AUTHOR]

The nonlinear, in-plane mechanics of a thin-walled honeycomb with zero Poisson's ratio under large deformation is investigated in this paper. A theoretical method for calculating in-plane tensile modulus, modified factors of linear constitutive relations of the honeycomb structures with zero Poisson's ratio is proposed based on the theory of Euler-Bernoulli beam and the bending theory of beam in large deflection, and a finite element simulation is given to validate. In addition, parametric analysis for revealing the impacts of geometrical configurations and material parameters on in-plane mechanical properties of the honeycombs have been studied systematically. These findings suggest that geometric and/or material parameters provide different contributions to the effective mechanical properties and lead to a separate design for the in-plane mechanical properties. After that, the effects of geometric and/or material nonlinearities on mechanical properties of the honeycomb structures with zero Poisson's ratio are revealed by considering the dimensionless tangent stiffness of the honeycombs. [ABSTRACT FROM AUTHOR]

Most natural materials have rotational and hierarchical properties, so they can show excellent mechanical properties such as shear resistance and impact resistance. In order to further improve the energy absorption characteristics of vibration absorbing structures, a new type of honeycomb structure with integral rotation and group rotation is designed and characterized. The effects of the geometrical parameters of rotation Angle on the impact deformation mode, stress response curve and energy absorption characteristics of the honeycomb structure are studied through numerical simulation and experimental design. The results show that the overall honeycomb performance of 15° is better than that of 0°, the specific energy absorption is the results show that the overall honeycomb performance of 15° is better than that of 0°, the specific energy absorption is increased by 6%, the bearing capacity is increased by 320 N, and the crushing force efficiency is increased by 2%. Compared with the whole cell and the group cell, the specific absorption energy increased by 35%, 73% and 71%. The results of this paper provide a new insight into the impact performance of monolithic and grouped rotating honeycomb structures, which is helpful for the results of this paper provide a new insight into the impact performance of monolithic and grouped rotating honeycomb structures, which is helpful for the optimization of crashworthiness structural design. [ABSTRACT FROM AUTHOR]

The dynamic characteristics of sandwich panels with a hierarchical hexagonal honeycomb (SP-HHHs) show significant improvements due to their distinct hierarchy configurations. However, this also increases the complexity of structural analysis. To address this issue, the variational asymptotic method was utilized to homogenize the unit cell of the SP-HHH and obtain the equivalent stiffness, establishing a two-dimensional equivalent plate model (2D-EPM). The accuracy and effectiveness of the 2D-EPM were then verified through comparisons with the results from a detailed 3D FE model in terms of the free vibration and frequency- and time-domain forced vibration, as well as through local field recovery analysis at peak and trough times. Furthermore, the tailorability of the typical unit cell was utilized to perform a parametric analysis of the effects of the length and thickness ratios of the first-order hierarchy on the dynamic characteristics of the SP-HHH under periodic loading. The results reveal that the vertices serve as weak points in the SP-HHH, while the vertex cell pattern significantly influences the specific stiffness and stiffness characteristics of the panel. The SP-HHH with hexagonal vertex cells has superior specific stiffness compared to panels with circular and rectangular vertex cells, resulting in a more lightweight design and enhanced stiffness. [ABSTRACT FROM AUTHOR]

Partial shading conditions considerably reduces the power generation for conventional PV array connection. This problem can be diminished effectively by repositioning the PV panels. In this paper, physical repositioning has been applied to series-parallel (SP), total-cross-tide (TCT), bridge link (BL), and honey-comb (HC) configurations without changing electrical connections. To relocate the panel we have adopted two repositioning strategies which are reconfiguration within an array (RWA) and reconfiguration within a column (RWC). This paper investigates the effect of repositioning of a panel on power extraction, efficiency, fill factor (FF), per cent mismatch losses (%ML), shading power losses (PL), and shade dispersion. This paper also provides information about, which conventional configuration gives maximum power extraction; either without reconfiguration or with reconfiguration. Also, the comparison in two base repositioning approaches shows the path for the next advancements in reconfiguration techniques. The performance analysis has done in MATLAB Simulink on a 4×4 PV array under horizontal, vertical, diagonal, L-shape, Left Top Corner (LTC), Right Top Corner (RTC), Right Bottom Corner (RBC), Left Bottom Corner (LBC), and Center shading patterns. [ABSTRACT FROM AUTHOR]

Honeycomb structures with zero Poisson's ratio show promising potential for application in variable-sweep wing aircraft. The shear properties of these honeycomb structures serve as a crucial indicator of their morphing capacity. This paper derives the linear and non-linear shear properties of a honeycomb structure with zero Poisson's ratio. A modified factor is introduced to establish a relationship between the linear and non-linear shear modulus of the honeycomb structure, simplifying the calculation method of the non-linear shear modulus. The validity of theoretical predictions is then confirmed using the finite element method Furthermore, the influences of the geometric parameters on the shear properties of the honeycomb structure with zero Poisson's ratio are investigated, highlighting the varying contributions of these cell geometric parameters to the shear properties. [ABSTRACT FROM AUTHOR]

Cellular hexagonal (conventional) and re‐entrant (auxetic) honeycombs are applicable in automotive, construction, and protective engineering. Auxetic structures own excellent energy absorption and flexural behavior due to their special deformation under loading. This work explores the performance of additively manufactured polylactic acid (PLA)‐ and thermoplastic polyurethane (TPU)‐based hexagonal and re‐entrant honeycombs under flexural loading via experimental three‐point bending (TPB) tests and finite‐element analysis (FEA). 3D‐printed conventional and auxetic cellular structures are filled with polyurethane (PU) foam and their energy absorption capacity and flexural modulus are compared with hollow structures. The results reveal that TPU‐based structures' energy absorption capacity and flexural modulus improve significantly, whereas the PLA‐based structures' performance deteriorates when filled with PU foam. Moreover, re‐entrant honeycombs are better reinforced with foam in comparison to the hexagonal honeycombs, as the re‐entrant's unit cell is more spacious than the hexagonal unit cell. Finally, parametric studies are performed via FEA to investigate the influence of geometric parameters of structures and flexural loading setup on the performance of the honeycombs, showing that structures with thicker struts and higher cell angle can act stiffer under TPB. The outcomes of this research indicate the promising performance of foam‐filled TPU‐based auxetic structures. [ABSTRACT FROM AUTHOR]

An improved star-shaped honeycomb (ISSH) is a kind of honeycomb structure with excellent performance. The main objective of this study was to provide some ideas for the optimization of the ISSH structure in ships. As a result, 2D-ISSH specimens were fabricated using 3D printing technology, and a quasistatic compression test was carried out to investigate the deformation mode and mechanical properties. The experimental results showed that the 2D-ISSH structure exhibited "V"-shaped and "-"-shaped deformation patterns with a double-platform stress stage. To further utilize the excellent performance of the structure and obtain a better negative Poisson's ratio effect and broader application, based on the properties of the 2D-ISSH specimen, a 3D-ISSH structure was proposed and a finite element simulation was carried out. The simulation results of the 3D-ISSH structure showed different deformation patterns, including "X"- shaped and "-"-shaped patterns. According to the deformation mechanism of typical cells, the stress formula for the 3D-ISSH double platform was derived, and the theoretical results agreed well with the numerical results. The effects of the structural design, materials, and dimensions on the mechanical properties, such as the energy absorption and negative Poisson's ratio, of the ISSH and similar structures were explored. The combined performance of various honeycombs was evaluated from multiple perspectives. [ABSTRACT FROM AUTHOR]

To investigate the effect of nodal configuration on the mechanical properties of hexachiral honeycombs, three specimens, namely, a standard honeycomb, a thickened-node honeycomb, and a filled-node honeycomb, were prepared using 3D-printing technology. Several quasi-static compression tests were performed, which revealed that nodal reinforcement can inhibit nodal aberrations during ligament winding, thus facilitating the "rotational" mechanism and improving the negative Poisson's ratio properties of the honeycomb. Experiments performed using the finite element method showed that nodal reinforcement mainly played a role in the stage of stress rise, and the role of nodal filling was more significant than that of nodal thickening. Low-strain standard honeycombs presented the highest specific absorption energy. However, the specific absorption energy of the filled-node honeycomb and the thickened-node honeycomb exceeded that of the standard honeycomb at a strain of 0.71. The conclusions presented herein can aid in the optimal design of honeycombs and contribute to the design of protective structures. [ABSTRACT FROM AUTHOR]

The magnetization process of the AA-stacked bilayer honeycomb spin lattice in the out-of-plane applied field is examined in the framework of the Ising model and mean field approximation. Competition between different kinds (antiferromagnetic: AF, or ferromagnetic: FM) of intra-layer and inter-layer spin exchange couplings could lead to the first order magnetization process, characterized by sharp jumps in magnetization curves occurring in critical external fields (spin-flop and spin-flip fields). There is only the spin-flip field at very low temperature and its magnitude depends not only on the intra-layer frustration level but also exchange coupling between spin layers. During the magnetization process, the initial AF bilayer honeycomb spin lattice may undergo ferrimagnetic or week-ferromagnetic states before reaching full ferromagnetic saturation state by the spin-flip field. The results of this work can be applied for an explanation of the spin-flip phenomenon registered in the AF bilayer CrI3. [ABSTRACT FROM AUTHOR]