Materials Science Research Articles

Current developments in elastic and acoustic metamaterials science.

The concept of metamaterial recently emerged as a new frontier of scientific research, encompassing physics, materials science and engineering. In a broad sense, a metamaterial indicates an engineered material with exotic properties not found in nature, obtained by appropriate architecture either at macro-scale or at micro-/nano-scales. The architecture of metamaterials can be tailored to open unforeseen opportunities for mechanical and acoustic applications, as demonstrated by an impressive and increasing number of studies. Building on this knowledge, this theme issue aims to gather cutting-edge theoretical, computational and experimental studies on elastic and acoustic metamaterials, with the purpose of offering a wide perspective on recent achievements and future challenges. This article is part of the theme issue 'Current developments in elastic and acoustic metamaterials science (Part 1)'.

C-H functionalization enabled by multiple isocyanides.

Past decades have witnessed significant advance of isocyanides as a class of versatile organic synthons as well as their broad applications in multi-component reactions (MCRs) and other tandem reactions. Reactions involving multiple isocyanides allow the construction of molecules with further diversification and complexity, while C-H functionalization emphasizes the advantages of high atom economy, broad substrate availability and great synthetic efficiency. This promising synergistic strategy of C-H functionalization involving multiple isocyanides provides a variety of valuable synthetic methods for organic chemists' toolbox and offers considerable potential in pharmaceutical chemistry and materials science as well. The present review outlines in detail various reaction types of C-H functionalization enabled by multiple isocyanides, and the relevant mechanistic rationale is discussed.

Highly sensitive biosensors for real-time monitoring of histamine at acupoint PC6 in rats based on graphene-modified acupuncture needles.

Acupoints are the local initial response sites of acupuncture therapeutic effects. As a biomarker, histamine is released into the acupoint region and plays its role concurrently as acupuncture needles are inserted into acupoints. Hence, real-time monitoring of histamine at acupoints is important to elucidate the effectiveness of the acupoint-activation process in acupuncture. Therefore, we developed highly sensitive acupuncture/Au particles/graphene biosensors by electrodeposition, brushing, and annealing methods based on bare acupuncture needles. We achieved a histamine detection limit of approximately 4.352 (±3.419) × 10-12 mol L-1 and good sensitivity of approximately 6.296 (±3.873) μA μM-1, with satisfactory specificity, repeatability, and stability in vitro, rendering them more competitive and suitable for real-time monitoring in vivo without causing additional damage. Subsequently, we conducted real-time histamine monitoring at non-acupoint and acupoint PC6 in rats, respectively. Our results showed minimal changes at the non-acupoint, whereas a trend of initial increase followed by a decrease was observed at acupoint PC6. The change in histamine concentration at acupoint PC6 reflected its involvement in the acupoint-activation procedure. Moreover, its peak position at ∼18 min could provide guidance for optimizing needle retaining time for maximum therapeutic effect. This work presents the first real-time in vivo monitoring of histamine at acupoints with high sensitivity and underscores the specificity of histamine release between non-acupoint and acupoint PC6, demonstrating great potential for elucidating the acupoint-activation mechanisms in acupuncture. Additionally, this work expands the application of nanomaterials in the integration of medicine and engineering, which is an important aspect of the future development of materials science.

Investigating the structural, electronic, and optical properties of the novel double perovskite K2AgBiI6 using DFT

In this groundbreaking study, we unveil the remarkable structural, electronic, and optical Properties of the newly discovered double perovskite material, K2AgBiI6, presenting a paradigm shift in materials science. The unique crystal structure and diverse atomic interactions inherent in this double perovskite make it an up-and-coming candidate for various technological applications, particularly in photovoltaics; owing to its stability and resistance to heat and humidity, we aim to shed light on the extraordinary potential of K2AgBiI6. Our study provides valuable insights for researchers engaged in tailored material design. We anticipate that the exceptional electronic properties of K2AgBiI6 will not only redefine the boundaries of materials engineering but also catalyze unprecedented advances in sustainable technology. Employing the powerful computational tool CASTEP, we conducted detailed electronic structure calculations within the framework of Density Functional Theory (DFT) to unravel the electronic properties of the double perovskite K2AgBiI6. Our investigation thoroughly explored structural properties, band structure, total density of states (DOS), and partial density of states (PDOS). Furthermore, we systematically examined the influence of different exchange-correlation functionals, including LDA, GGA, and m-GGA, on the electronic and optical features of the material by presenting a comparative analysis of these approximations.

Transition‐Metal‐Free Chemo‐Selective C−C/C−N Bond Formation Reaction for the Highly Efficient Synthesis of Pyrazoles, Pyrazolo fused Pyrimidines and Pyridines

AbstractPyrazoles and pyrazolo fused pyrimidines and pyridines are well known for their applications in various fields like pharmaceuticals, agrochemicals and materials sciences. Keeping this in mind herein, we have developed the transition‐metal‐free approach for the chemo‐selective synthesis of the pyrazole and its derivatives from acetopheneones. The selectivity of the reaction can easily be tuned by shifting reaction from acidic to basic medium for the synthesis of pyrazolo‐pyrirmidines and pyrazolo‐pyridines respectively. The reaction shows excellent functional group tolerance in the form of −F, −Cl, −Br, −NMe2, −OH, −OMe, and −B(OH)2 in good yields.

Design of Point Charge Models for Divalent Metal Cations Targeting Quantum Mechanical Ion–Water Dimer Interactions

Divalent metal cations are of vital importance in biochemistry and materials science, and their structural and thermodynamic properties in aqueous solution have often been used as targets for the development of ion models. This study presented a strategy for designing nonbonded point charge models of divalent metal cations (Mg2+ and Ca2+) and Cl− by targeting quantum mechanics (QM)-based ion–water dimer interactions. The designed models offered an accurate representation of ion–water interactions in the gas phase and showed reasonable performance for non-targeted properties in aqueous solutions, such as the ion–water oxygen distance (IOD), coordination number (CN), and density and viscosity of MgCl2 and CaCl2 solutions at low concentrations. Our metal cation models yielded considerable overestimates of the hydration free energies (HFEs) of the ions, whereas the Cl− model displayed good performance. Together with the overestimated density and viscosity of the salt solutions, these results indicated the necessity of re-optimizing ion–ion interactions and/or including polarization effects in the design of ion models. The designed Mg2+ model was capable of maintaining the crystal metal-binding networks during MD simulation of a metalloprotein, indicating great potential for biomolecular simulations. This work highlighted the potential of QM-based ion models to advance the study of metal ion interactions in biological and material systems.

Towards an EPR on a Chip Spectrometer for Monitoring Radiation Damage During X-ray Absorption Spectroscopy

AbstractElectron paramagnetic resonance (EPR) spectroscopy is an essential tool to investigate the effects of ionizing radiation, which is routinely administered for reducing contaminations and waste in food products and cosmetics as well as for sterilization in industry and medicine. In materials research, EPR methods are not only employed as a spectroscopic method of structural investigations, but also have been employed for detection of changes in electronic structure due to radiation damage from high energy X-rays, for example, to monitor radical formation inside biomolecules caused by X-ray irradiation at carbon, nitrogen, and oxygen K-edges at synchrotron facilities. Here a compact EPR spectrometer, based on EPR-on-a-chip (EPRoC) sensor and a portable electromagnet, has been developed as a solution for monitoring radiation damage of samples during their investigation by X-ray absorption spectroscopy (XAS) at synchrotron facilities. A portable electromagnet with a soft iron core and forced air temperature stabilization was constructed as the source of the external magnetic field. The sweep range of magnetic field inside the most homogeneous region of the portable electromagnet is 12–290 mT. The compact spectrometer performance was evaluated by placing the EPRoC sensor inside either a commercial electromagnet or the portable electromagnet to record the EPR spectrum of tempol, irradiated alanine, and dilithium phthalocyanine (Li2Pc). The potential performance of the portable spectrometer for the detection of radiation damage in organic compounds and transition metal-containing catalysts during XAS measurements in both fluorescence and transmission modes was calculated with promising implications for measurements after implementation in a synchrotron-based XAS spectrometer.

First Principles Calculation of the Effect of Cu Doping on the Mechanical and Thermodynamic Properties of Au-2.0Ni Solder

To meet the demands for high-temperature performance and lightweight materials in aerospace engineering, the Au-Ni solder is often utilized for joining dissimilar materials, such as Ti3Al-based alloys and Ni-based high-temperature alloys. However, the interaction between Ti and Ni can lead to the formation of brittle phases, like Ti2Ni, TiNi, and TiNi3, which diminish the mechanical properties of the joint and increase the risk of crack formation during the welding process. Cu doping has been shown to enhance the mechanical properties and high-temperature stability of the Au-Ni brazed joint’s central area. Due to the difficulty in accurately controlling the solid solution content of Cu in the Au-Ni alloy, along with the high cost of Au, traditional experimental trial-and-error methods are insufficient for the development of Au-based solders. In this study, first principles calculations based on density functional theory were employed to analyze the effect of Cu content on the stability of the Au-2.0Ni-xCu (x = 0, 0.25, 0.5, 0.75, 1.0, 1.25 wt%) alloy phase structure. The thermal properties of the alloy were determined using Gibbs software fitting. The results indicate that the Au-2.0Ni-0.25Cu alloy exhibits the highest plastic toughness (B/G = 5.601, ν = 0.416, Cauchy pressure = 73.676 GPa) and a hardness of 1.17 GPa, which is 80% higher than that of Au-2.0Ni. This alloy balances excellent strength and plastic toughness, meeting the mechanical performance requirements of brazed joints. The constant pressure specific heat capacity (Cp) of the Au-2.0Ni-xCu alloy is higher than that of Au-2.0Ni and increases with Cu content. At 1000 K, the Cp of the Au-2.0Ni-0.25Cu alloy is 35.606 J·mol−1·K−1, which is 5.88% higher than that of Au-2.0Ni. The higher Cp contributes to enhanced high-temperature stability. Moreover, the linear expansion coefficient (CTE) of the Au-2.0Ni-0.25Cu alloy at 1000 K is 8.76 × 10−5·K−1, only 0.68% higher than Au-2.0Ni. The lower CTE helps to reduce the risk of solder damage caused by thermal stress. Therefore, the Au-2.0Ni-0.25Cu alloy is more suitable for brazing applications in high-temperature environments due to its excellent mechanical properties and thermal stability. This study provides a theoretical basis for the performance optimization and engineering application of the Au-2.0Ni-xCu alloy as a gold-based solder.

Direct Growth of Wafer-Scale Self-Separated GaN on Reusable 2D Material Substrates.

Free-standing gallium nitride has been prepared using various methods; however, the removal of the original substrate is still challenging with low success rates. In this work, 2-inch free-standing GaN films are obtained by direct growth on a fluoro phlogopite mica by hydride vapor-phase epitaxy. Depending on the van der Waals (vdW) interaction between GaN and mica, the effect of the significant lattice mismatch is effectively reduced; thus, enabling the production of a high-quality wafer-scale GaN film on mica. The vdW-induced cracks at GaN-mica interface are found to be initiated near the interface so that GaN can easily separate from mica during rapid cooling. Owing to the hydrophilic nature of mica, the residual GaN on the mica can be lifted off by following deionized water treatment, and the mica substrate can be repeatedly used to grow free-standing GaN films. The self-separated GaN films grown on both pristine and used mica substrates are single crystallinity and strain-free. Additionally, a fully functional ultraviolet light-emitting diode is demonstrated to show that the self-separated GaN films are of device quality. The proposed approach achieves epitaxial growth of wafer-scale single-crystalline GaN on 2D materials and provides a new substrate option in the technology of III-V materials.

THE ROLE OF LIFESTYLE-RELATED TREATMENTS FOR IRRITABLE BOWEL SYNDROME

Introduction: The role of diet and lifestyle in Irritable Bowel Syndrome (IBS) mainly involves alleviating symptoms and improving the quality of life for patients. Diet plays a significant role through the identification and avoidance of trigger foods, the introduction of an appropriate amount of fiber, and adherence to specific guidelines. Lifestyle, including regular physical activity, stress reduction techniques, and healthy sleep habits, also contributes to the reduction of bowel discomfort. Aim of the study: The aim of this study is to examine the relationship between diet and lifestyle, and the occurrence and course of Irritable Bowel Syndrome. Material and Methods of Research: A literature review focused on keywords related to the topic was performed using databases such as PubMed and Google Scholar, as well as textbooks and articles on websites. Results: Irritable Bowel Syndrome (IBS) is a chronic functional disorder of the gastrointestinal tract, primarily characterized by abdominal pain and changes in bowel habits. Dietary modifications, such as a lowFODMAP diet, and lifestyle factors, including physical activity levels, stress management, and meal regularity, significantly influence the course of the disease. There are gender differences in symptomatology and psychosocial impact as well as gender-specific responses to pharmaceutical treatments. Ongoing research is needed to better understand the mechanisms underlying IBS and to optimize therapeutic strategies. Conclusion: The effectiveness of IBS therapy requires a comprehensive approach that includes dietary modifications, increased daily physical activity, learning to manage emotions, and regular collaboration with a doctor. Understanding and implementing these elements are crucial for effectively alleviating symptoms and improving the functioning of patients with Irritable Bowel Syndrome.

Strategic Design and Mechanistic Understanding of Vacancy-Filling Heusler Thermoelectric Semiconductors.

Doping narrow-gap semiconductors is a well-established approach for designing efficient thermoelectric materials. Semiconducting half-Heusler (HH) and full-Heusler (FH) compounds have garnered significant interest within the thermoelectric field, yet the number of exceptional candidates remains relatively small. It is recently shown that the vacancy-filling approach is a viable strategy for expanding the Heusler family. Here, a range of near-semiconducting Heuslers, TiFexCuySb, creating a composition continuum that adheres to the Slater-Pauling electron counting rule are theoretically designed and experimentally synthesized. The stochastic and incomplete occupation of vacancy sites within these materials imparts continuously changing electrical conductivities, ranging from a good semiconductor with low carrier concentration in the endpoint TiFe0.67Cu0.33Sb to a heavily doped p-type semiconductor with a stoichiometry of TiFe1.00Cu0.20Sb. The optimal thermoelectric performance is experimentally observed in the intermediate compound TiFe0.80Cu0.28Sb, achieving a peak figure of merit of 0.87 at 923 K. These findings demonstrate that vacancy-filling Heusler compounds offer substantial opportunities for developing advanced thermoelectric materials.

Evaluate the Dynamic response of Buildings to Seismic Forces, Considering the Interaction between human Occupants and Structural vibrations

Damage to buildings and other structures may occur when dynamic loads, caused by earthquake vibrations, drive the ground and everything related to it to shake in a complicated way. Civil engineers are always thinking of new methods to deal with this inevitable problem. Humans put stress on a variety of buildings, including floors, footbridges, stadiums, and more. Modern material and manufacturing technology, together with human desire for aesthetics, have made it possible to build long span structures like bridges, stadiums, floors, etc. that are sleek, lightweight, and slim. To dampen a structure's dynamic reaction, engineers use devices called (TMDs), which consist of a mass and a spring, are tuned mass dampers. When it comes to managing the structural reactions to wind and harmonic excitations, Tuned Mass Damper (TMD) is the way to go. Specifically, the shear beam and 1D lumped-mass beams are the models under consideration. The main purpose of this piece is to demonstrate how methods that use records of ambient vibration may enhance and supplement seismic risk assessments of preexisting structures. To compare the structure's reaction with and without TMD, or tuned mass damper, is mounted on the building's exterior. Using a model calculated from outside vibrations and recorded within the structure, we were able to effectively compare the building's motion to a fake ground motion. It was also determined the inter-storey drift and the stiffness of each floor.

Study on MHD Pulses, Waves, and Instability in Trigging multiple renewables noise on various spectral information scales

Major concepts covered in this research include: State of being free vibration and method start changing; MHD waveguides like the magnetic properties dorsal fin, radicular groups, and radicular streaming sites; processes for frequency supplied in imperativeness overflows throughout sub hurricanes and solar activity; the possibility of Heat diffusion resonant frequencies along empty field lines; potential motorists of MHD waves; diagnostic tools of plasma screens with MHD waves; the collaboration of MHD waves mostly with positive ions limits (ionosphere and chromosphere). This review is directed largely at experts in the subjects of magnetosphere material science and solar theoretical physics, while it does delve into the intricacies of the surround investigation fields to those who are concerned. Though there are several noise contributors, aerodynamics is the most significant. When it concerns to aerodynamics noise, the distal end of blades of wind turbines is where the majority of the action occurs. A subject of this research is on blade tip noise caused by wind generators, and an evaluation and comparison of the many methods being used and researched to minimize this difficulty is the paper's primary focus. Subjective assessment outcomes are also compared to quantifiable measurements. Several methods are proposed, and the risks and benefits are compared. Among the most intriguing instances of plasma in reality that we're able to examine close quarters are really the Solar energy, Atmosphere's geomagnetic, and stratosphere. Were very could be used to model such plasmas effectively in principle (MHD). In MHD, the statistics and dynamics of liquids that conduct electricity are hypothetically characterized.

Understanding the Role of Solvent on the Growth of Zinc Oxide: Insight from Experiment and Molecular Dynamics Simulations.

The controlled synthesis of nanoparticles with tailored shapes and morphologies has garnered significant attention, driven by the ever-growing demand for advanced materials with defined properties. In nanoparticle formation, various parameters influence the final product, and among these, the solvent plays a pivotal role, as it constitutes the major component of the reaction medium. In this work, the critical role of solvents in controlling the growth of zinc oxide (ZnO) nanoparticles was investigated, with a focus on simple primary alcoholic solvents as the reaction medium. A model reaction based on the direct solvolysis of anhydrous zinc acetylacetonate was employed to probe the influence of different primary alcohols, specifically methanol, ethanol, and their mixture. A substantial difference in the preferential growth direction of the ZnO nanocrystals in methanol and ethanol was observed through XRD and was further proven through TEM. Thereby, in ethanol, a preferential growth in the [001] direction was observed, resulting in short nanorods as primary particles, while this growth was inhibited in methanol, leading to platelet- or sheet-like primary particles. To unravel the underlying mechanisms responsible for the observed solvent-dependent variations, molecular dynamics (MD) simulations were employed using an optimized interface force field to model the ZnO-alcohol interaction. These simulations provide valuable insights into the preferential adsorption of the solvent molecules onto the polar (0001) and (0001̅) and nonpolar (101̅0) ZnO surfaces, shedding light on the fundamental interactions driving the shape control phenomenon. Essentially, the experimental observations on primary particle morphology could be explained well by the adsorption behavior determined by the MD simulations. Furthermore, this report provides an extensive comparison with various similar reaction systems for ZnO synthesis, deriving correlations with the findings from the model system. These insights contribute to a deeper understanding of the intricate interplay between solvent properties and nanoparticle growth, offering a valuable toolkit for designing and optimizing the synthesis of ZnO nanoparticles with specific shapes and functionalities.

One-step Pulsed Laser Deposition of Carbon/Metal oxynitride Composites for Supercapacitor Application

Abstract Advanced material composite of nanocarbons and metal-based materials provides a synergistic effect to obtain excellent electrochemical charge-storage performance and other properties. Herein, 3D porous carbon-metal oxynitride nanocomposites with tunable carbon/metal and oxygen/nitrogen ratio are synthesized uniquely by simultaneous ablation from two different targets by single-step pulsed laser deposition at room temperature. Co-ablation of titanium and vanadium nitride targets together with graphite allowed us to synthesize carbon-metal oxynitride porous nanocomposite and exploit them as a binder-free thin film supercapacitor electrode in
aqueous electrolyte. We show that the elemental composition ratio and hence the structural properties can be tuned by selecting target configuration and by manipulating the ablation position. We investigate how this tuning capability impacts their charge-storage performances. We anticipate the utilization of as-synthesized various composites in a single PLD production run as next-generation active materials for flexible energy storage and optoelectronic applications.

Atomic Phosphorus Sites for Anchoring Platinum–Tungsten Dimers to Facilitate Proton Transfer in All‐pH Hydrogen Evolution

AbstractBimetallic single‐atom‐dimer (SAD) with unique electronic structures and adsorption properties presents exceptional catalytic performance owing to atomic‐level synergistic effects from direct bonding between different metal atoms. However, inherent characteristics of substrate present great challenges in their synthesis and mechanism investigation. Herein, a unique phosphorus modified atomic layer deposition (P‐ALD) strategy is designed to synthesize P‐anchored Pt–W dimers, overcoming substrate limitation (Pt1W1–P/C). Motivated introduction of atomic P site via ALD can effectively anchor one‐to‐one AB bimetallic dimer structure on various substrates, confirmed by X‐ray absorption spectroscopy (XAS). Density functional theory reveals an interatomic synergistic adsorption mechanism, with W as primary hydrogen adsorption site extending to Pt, optimizing hydrogen coverage, leading to 60‐fold increase in mass activity compared to commercial Pt/C in both acidic and alkaline electrolytes. Anion exchange membrane water electrolyzer with ultra‐low loading Pt1W1–P/C (50 µgPt cm−2) catalyst operates durability at 1000 mA cm−2 for 550 h with ultra‐low degradation of 38 µV h−1. Operando XAS confirms hydrogen adsorption pathway between atoms and remarkable self‐healing ability of P–Pt–W–O sites under all‐pH conditions. These findings extend the application domain of SAD to catalytic manufacturing methods and aid in designing advanced materials with multi‐atomic active sites.

Semi-IPN polysaccharide-based hydrogels for effective removal of heavy metal ions and dyes from wastewater: a comprehensive investigation of performance and adsorption mechanism

Abstract The escalating issue of environmental pollutants necessitates efficient, sustainable, and innovative wastewater treatment technologies. This review comprehensively analyzes the mechanisms and isotherms underlying the adsorption processes of semi-interpenetrating polymer network (semi-IPN) polysaccharide-based hydrogels to remove heavy metal ions and dyes from wastewater. Polysaccharides are extensively utilized in hydrogel synthesis due to their biocompatibility, cost-effectiveness, and non-toxic nature. The synthesis of these hydrogels as semi-IPNs enhances their mechanical and structural robustness and adsorption capacity. This review explores the key parameters affecting adsorption performance, including pH, temperature, contact time, and adsorbent dosage. Findings highlight that semi-IPN polysaccharide-based hydrogels exhibit remarkable adsorption capabilities through electrostatic interactions, ion exchange, and surface complexation. Furthermore, this review highlights the distinct advantages of semi-IPNs over other polymer networks. Semi-IPNs offer improved mechanical stability, higher adsorption efficiencies, and better reusability, making them a promising solution for wastewater treatment. Detailed isotherm models, including Langmuir and Freundlich isotherms, were studied to understand these hydrogels’ adsorption behavior and capacity for different pollutants. This study highlights the potential of semi-IPN polysaccharide-based hydrogels as effective adsorbents for heavy metals and dyes and as a promising solution for mitigating environmental pollution. The insights provided herein contribute to developing advanced materials for environmental remediation, aligning with global sustainability goals, and advancing wastewater treatment technology.

Pronounced Cold Crystallization and Hydrogen Bonding Distortion of Water Confined in Microphases of Double Zwitterionic Block Copolymer Aqueous Solutions.

Advanced materials leveraging water control are garnering considerable interest, with the state of water emerging as a critical aspect of material design. This study explored the impact of microphase separation on water using aqueous solutions of double zwitterionic diblock copolymers, specifically poly(carboxybetaine methacrylate) and poly(sulfobetaine methacrylate) (PCB2-b-PSB4). These copolymers form a mesoscale periodic ordered lattice structure consisting of two distinct aqueous phases. Through differential scanning calorimetry and X-ray emission spectroscopy, it was found that water in these PCB2-b-PSB4 aqueous solutions exhibits pronounced cold crystallization and subtle distortions in hydrogen-bonding configurations.

Copper ions-photo dual-crosslinked alginate hydrogel for angiogenesis and osteogenesis.

Early healing of bone defects is still a clinical challenge. Many bone-filling materials have been studied, among which photocrosslinked alginate has received significant attention due to its good biocompatibility and morphological plasticity. Although it has been confirmed that photocrosslinked alginate can be used as an extracellular matrix for 3D cell culture, it lacks osteogenesis-related biological functions. This study constructed a copper ions-photo dual-crosslinked alginate hydrogel scaffold by controlling the copper ion concentration. The scaffolds were shaped by photocrosslinking and then endowed with biological functions by copper ions crosslinking. According to in vitro research, the dual-crosslinked hydrogel increased the compressive strength and favored copper dose-dependent osteoblast differentiation and cell surface adherence of rat bone marrow mesenchymal stem cells and the expression of type I collagen (Col1), runt-related transcription factor 2 (Runx2), osteocalcin (OCN), vascular endothelial growth factor (VEGF). In addition, hydrogel scaffolds were implanted into rat skull defects, and more angiogenesis and osteogenesis could be observed in in vivo studies. The above results show that the copper-photo-crosslinked hydrogel scaffold has excellent osseointegration properties and can potentially promote angiogenesis and early healing of bone defects, providing a reference solution for bone tissue engineering materials.

Study on interface bonding and mechanical properties of arc-shaped bamboo-poplar wood composites

The bamboo-wood composite is a high-performance product that utilizing the strengths of both materials, which also can effectively reduce the weight of the composite material. An equal arc-shaped bamboo split has been studied by our research group, which retains the natural arcuate structure and achieves a utilization rate of approximately 85%. Based on this, a new composite made of arc-shaped bamboo split and poplar wood is prepared in this paper. And another material made of flattened bamboo and poplar wood also prepared as a control. The mean flexural modulus and strengths for arc-shaped bamboo split were 12179.33MPa and 195.77MPa respectively, the shear strength of the adhesive layer in the composite of arc-shaped bamboo and poplar wood was a robust 8.02MPa. The flexural maximum load of arc-shaped bamboo-poplar composite was 9896.29N, nearly twice as much as that of flattened bamboo-poplar composite, whose excellent performance was expected to exceed the requirements of industrial products. The phenol-formaldehyde (PF) adhesive penetrated into the bamboo and wood quite deeply, allowing it to secure the two pieces of board together like many small glue nails. Besides the physical connections, lots of effective chemical bonding were formed between PF and the two boards. In addition, it was also found that the fracture mode of arc-shaped bamboo and poplar wood composites was ductile fracture, which was different from the brittle fracture mode of traditional bamboo and wood composites. Overall, this new arc structural composite material has high performance and will expand the application of bamboo engineering materials in industry products.