Application Of Materials Research Articles

PH‐Tunable 3D Interconnected Network of Multiwalled Carbon Nanotubes /Polyacrylic Acid Hydrogel with Excellent Electromagnetic Radiation Shielding Capability

AbstractThe fabrication of durable and high anticorrosion hydrogel composite materials composed of multi‐walled carbon nanotubes (MCNTs) and crosslinked polyacrylic acid (PAA) for EMI shielding application is reported. The MCNTs contribute to the generation of 3D porous structures and enhance the mechanical properties of composite hydrogel. The 3D porous structure and high electrical conductivity inherited from ultrahigh electrically conductive MCNTs enable excellent EMI shielding properties with a total shielding efficiency EMI SE (SET) value of 32.8 dB (>99.9%) at only 3 wt% filler content of MCNTs. The MCNTs/PAA hydrogels also display superior EMI shielding performance under a strong acidic environment with SET > 99.99% while the 3D porous structure remained intact. The combination of electron–ion system in pH solution enriches the charge transfer and accumulation, enabling dipole orientation and polarization that are favorable for enhancing EMI attenuation. Moreover, the porous structure of MCNTs/PAA also contributes to partial trapping and dissipation of EM radiation energy via multiple scattering phenomena. This work thus paves the way toward applications of 3D hierarchical network materials for EMI shielding applications in both land and aqueous environments.

Carangiform‐Like Magnetic Milliswimmer With Negative Buoyancy for Agile 3D Navigation in Confined Fluid Environments

AbstractMiniature soft robots designed with magnetoelastic materials have the potential for noninvasive navigation in narrow spaces and innovative clinical therapies. However, the complex environment inside the body imposes stringent requirements on the motility and environmental adaptability of robots. Inspired by carangiform fish morphology and kinematics, a 3D free‐swimming magnetic milliswimmer with enhanced controllability, maneuverability, and environmental adaptability is developed. This milliswimmer is negatively buoyant like most fishes and employs magnetic torque to actuate its body. It mimics fish muscle contractions and generates a carangiform‐like body curvature distribution that results in comparable swimming behavior and performance. Compared with previous designs, it achieves over six times the equivalent motion performance and enables gravity‐resisting free‐swimming, with fish‐like maneuverability (a minimum turning radius of just 0.05 body length and a maximum turning rate of up to 4737 deg s−1). Its ability to transport and release cargo precisely while navigating three‐dimensionally in an ex vivo porcine urinary system is demonstrated. The designed bionic magnetic soft robot is expected to advance biomedical applications of magnetoelastic materials, particularly in urinary and other clinical treatments.

Antibacterial nonwoven materials in medicine and healthcare.

Bacterial infection has always been a severe challenge for mankind. The use of antibacterial nonwoven materials provides a lot of convenience in daily life and clinical practice grammar revision, it has become an important solution to avoid bacterial infection in clinical and daily life. This review systematically examines the spin bonding, melt blown, hydroneedling and electrospinning methods of nonwoven fabrication materials, and summarizes the antibacterial nonwoven materials fabrication methods. Finally, the review discusses the applications of antibacterial nonwoven materials for medical protection, external medical and healthcare, external circulation medical care implantable medical and healthcare and intelligent protection and detection. This comprehensive overview aims to provide valuable insights for the advancement of antibacterial nonwoven materials in the domain of medicine and health care. In the future, antibacterial nonwoven materials are expected to evolve towards biodegradability, composite materials, functionalization, minimally invasive techniques, diversification, and intelligence, thereby holding immense potential in healthcare.

A review on synthesis, structural properties and applications of metal oxide-based thin film thermoelectric materials

A review on synthesis, structural properties and applications of metal oxide-based thin film thermoelectric materials

Near-complete extraction of maximum stored energy from large-core fibers using coherent pulse stacking amplification of femtosecond pulses

High field science relies on ultrashort pulse lasers with multi-joule pulse energies for studying light–matter interactions under extreme conditions and for driving particle accelerators and secondary radiation sources of x rays, gamma rays, neutrons, positrons, muons, and protons. Next-generation laser drivers will require a 103−104 times increase in pulse repetition rates, producing multi-joule energies at multi-kilowatt average powers to enable practical applications in nuclear engineering, advanced materials, medicine, biology, homeland security, and high-energy physics. Spatially coherently combined femtosecond fiber lasers are recognized as a pathway to these next-generation drivers, with significant practical advantages including high efficiency and the possibility of compact integration. However, chirped pulse amplification in fibers is capable of extracting only a small fraction (usually ∼1%) of the maximum stored energy. Here we demonstrate near-complete maximum stored energy extraction with low accumulated nonlinearity from a large-core fiber amplifier using coherent pulse stacking amplification. We have amplified a 81-pulse stacking burst in a 85 µm core chirally coupled core Yb-doped fiber, extracting up to 9.5 mJ (∼90% of stored energy) with <4.5 radians of accumulated nonlinear phase, temporally combined this burst into a single pulse, and achieved 4.2 mJ pulses of 313 fs bandwidth-limited duration after compression. This represents, to our knowledge, the highest energy extracted and compressed into a femtosecond pulse from a single fiber amplifier, enabling approximately two orders of magnitude size reduction of future high-energy coherently spatially combined fiber laser arrays.

Tunable Lotus Leaf Effect by Three-Dimensionally Printed Stretchable Objects.

Adjustable wettability is important for various fields, such as droplet manipulation and controlled surface adhesion. Herein, we present high-resolution 3D stretchable structures with tunable superhydrophobicity, fabricated by a stereolithography-based printing process. The printing compositions comprise nonfluorinated monomers based on silicone urethane with dispersed hydrophobic silica particles. 3D lotus-like structures were designed and printed, having microsize pillars located at the external surfaces, with controlled dimensions and interspacing. The design of the pillars and the presence of the hydrophobic silica particles resulted in superhydrophobicity due to the surface structuring and entrapment of air between the pillars. The best structures display a contact angle of 153.3° ± 1.3° and rolling angle of 3.3° ± 0.5°, and their self-cleaning, water repellency, and buoyancy are demonstrated. The durability of the structure over time, water immersion, and heat exposure were tested, confirming the preservation of superhydrophobicity under these conditions. Upon stretching the surfaces, the interpillar distances change, thus enabling tuning the wetting properties and achieving good control over the contact and rolling angles, while the stretching-induced superhydrophobicity is reversible. This approach can expand the potential applications of superhydrophobic soft materials to fields requiring control over the wetting properties, including soft robotics, biomedical devices, and stretchable electronics.

Recent Advances in NIR-Switchable Multi-Redox Systems Based on Organic Molecules.

In recent years, near-infrared (NIR) dyes, exhibiting absorption in the NIR region (750-2500 nm), have been applied to various optical applications such as security marking, photovoltaic cells and chemotherapy of deep tissues in vivo. Electrochromic systems capable of switching NIR absorption are attractive from the viewpoint of applications for material and life science, and thus several examples have been reported to date. The development of organic-based materials is needed to reduce the environmental impact and improve biocompatibility, however, the switching of NIR absorption based on redox interconversion is still a challenging issue regarding reversibility and durability during interconversion. To overcome this potential instability, several studies on organic electrochromic systems that allow ON/OFF switching of NIR absorption have been developed in recent years. In this review, we focus on redox-active well-defined small molecules that enable ON/OFF switching of NIR absorption, and present recent studies on their intrinsic electrochemical and spectroscopic properties and/or structural characterization of their charged states. We also address more sophisticated electrochromic systems that can modulate their properties in response to external stimuli such as light, heat, and electric potential.

Intercomparison of Indexable Cutting Inserts’ Wear Progress and Chip Formation During Machining Hardened Steel AISI 4337 and Austenitic Stainless Steel AISI 316 L

This article deals with a mutual comparison of indexable cutting inserts of the CNMG 120408 type from two different manufacturers during the machining of hardened steel AISI 4337 and austenitic stainless steel AISI 316 L. The main goal is to analyse the different wear processes depending on the difference in the manufacturer’s design and also depending on the properties of the different machined materials. The progress of the wear of the main spine of the tool, the types of wear and the service life of the cutting edge were monitored, with the achievement of the critical value VBmax = 300 µm being the standard. In addition to the wear of the inserts, the production of chips was monitored in terms of their shape, average size and number of chips per 100 g of chips produced. In order to understand the relationships arising from the obtained data, an SEM equipped with an elemental analyser was used to analyse the coating layers and the substrate of the unworn inserts and the types of wear and the intensity of the surface damage of the worn inserts. A several-fold difference in the lifetime of the cutting edge was found, both in terms of design and in terms of the selected machined material, while in both cases the cutting edge with Al2O3 and TiCN layers of half thickness achieved a better result in liveness. From the point of view of chip formation, very similar results in shape and average length were observed despite the different designs of chip breakers. Cutting inserts with half the thickness of the coating layers achieved longer cutting edge life in the non-primary material application compared to the target workpiece material. At the same time, it was observed that a thinner coating layer has a positive effect on chip formation in terms of its length and shape.

Randomized Clinical Study of Nano-Cerium Oxide and its Efficacy in Sciatic Nerve Regeneration: A Histopathological Evaluation

Background: Peripheral nerve damage is a frequent clinical condition. peripheral nerve injuries are variable, and these injuries are mostly caused by trauma. Blunt trauma has many types, including contusion, laceration, stretching, traction, penetrating and perforating injuries, abnormal sleeping positions, external pressure, internal compression, ischemia. Cerium oxide nanoparticles are used widely in the materials field. Besides their material applications. Objective: this study was examining how cerium oxide nanoparticles impact axonal regeneration of the sciatic nerve in rats. Materials and Methods: 24 adult animals used, weighing average (M±SD: 230 ± 20 g). The animals were separated into two group. The first group (control) was left without treatment, The second group (Nano cerium Oxide) was treated orally with 50 mg of Nano cerium oxide daily for 7 days. Right Sciatic nerve was completely transected in all animals. The result evaluated at 4th, 8th and 12th weeks post-operative. Results: The histopathological results, indicated that the high effective result in the second group, then the control group. The control group has a significant nerve damage and some regenerative signs over time. While there are indications of severe damage particularly at 4 and 8 weeks, then presence of almost normal nerve fibers at 12 weeks suggests partial recovery. Conclusion: Nano Cerium Oxide accelerated the regeneration of the peripheral nerves These findings suggest that this nanoparticle could can be seen as a novel therapy for promoting the regeneration of the nervous system.

Myrrh Oleo‐Gum Resin as a Functional Additive in Pectin and κ‐Carrageenan Composite Films for Food Packaging

ABSTRACTMyrrh oleo‐gum‐resin (MOGR) is a natural substance that has a rich history of medicinal use due to its anti‐inflammatory, antimicrobial, and antioxidant properties. The present study reports on the fabrication and assessment of pectin and K‐carrageenan composite films infused with varying proportions (0.3%, 0.5%, and 0.7%) of MOGR. Morphological analysis of the film samples was conducted using Scanning Electron Microscopy (SEM) and Atomic Force Microscopy (AFM). The results indicated that the introduction of MOGR led to a notable increase in surface roughness. The SEM micrographs of the films showed that the MOGR addition had an important effect on the microstructure of the film. The surface hydrophobicity of the MOGR‐loaded films increased, as confirmed by the rise in the contact angle. Moreover, there was an increase in the thickness (0.062 ± 0.004–0.095 ± 0.006 mm) and opacity (1.24 ± 0.07–9.41 ± 0.24) of the films with the addition of MOGR; however, tensile strength (7.30 ± 0.50–4.92 ± 0.34 MPa), elongation at break (32.41% ± 1.0%–29.70% ± 0.24%), and barrier properties decreased. Additionally, a rise in MOGR concentration corresponded to a rise in overall color difference ΔE (0.77 ± 0.03–5.09 ± 0.49) of the films. Notably, the incorporation of MOGR led to an increase in the antioxidant activity of the composite films, indicating potential applications in functional packaging materials.

Construction and 3D Printing of Multiscale Silk Fiber‐Cellulose Composite Networks Based on Ionic Liquids

AbstractMicroscopic defects in the amorphous regions of natural cellulose affect the mechanical properties of their materials. After dissolution and regeneration, cellulose's mechanical properties are still insufficient for application in advanced materials. Conventional compounding and crosslinking techniques with toxic crosslinking agents are not only cumbersome, but also have limited performance enhancement in cellulose materials Therefore, much attention has been paid to designing and developing more straightforward and efficient cellulose reinforcement technologies. Herein, an in situ multiscalarization strategy is used to form multiscale silk fiber‐cellulose composites (MS‐C) by the gradual nanosizing of silk fibers (SF) under heating in a 1‐butyl‐3‐methylimidazolium chloride solution of cellulose (Cel‐BmimCl). MS‐C are constructed from micro and nano SF, fibroin chains, and cellulose molecules into a multidimensional network. Due to its advantage of multiscale structure, MS‐C has excellent mechanical properties, the tensile strength and Young's modulus, which are 123.06% and 91.68% higher than that of pure regenerated cellulose after 5h heating treatment. Besides, MS‐C has good biocompatibility and can be molded or 3D printed with direct ink writing, showing broad application prospects in medical, bioengineering, and other fields. This multiscale enhancement strategy can also be extended to the research and application of biopolymers such as natural polysaccharides or proteins.

Application of Fetal Membranes and Natural Materials for Wound and Tissue Repair

The human fetal membrane is a globally accepted biological biomaterial for wound and tissue repair and regeneration in numerous fields, including dermatology, ophthalmology, and more recently orthopedics, maxillofacial and oral surgery, and nerve regeneration. Both cells and matrix components of amnion and chorion are beneficial, releasing a diverse range of growth factors, cytokines, peptides, and soluble extracellular matrix components. Beside fetal membranes, numerous natural materials have also been reported to promote wound healing. The biological properties of these materials may potentiate the pro-healing action of fetal membranes. Comparison of such materials with fetal membranes has been scant, and their combined use with fetal membranes has been underexplored. This review presents an up-to-date overview of (i) clinical applications of human fetal membranes in wound healing and tissue regeneration; (ii) studies comparing human fetal membranes with natural materials for promoting wound healing; and (iii) the literature on the combined use of fetal membranes and natural pro-healing materials.

Luminous Fish‐Inspired Hydrogels with Underwater Long‐Lived Room Temperature Phosphorescence

AbstractSome marine animals form long‐lived luminescence for predation, communication, camouflage, and anti‐predation. These marine animals demonstrate soft nature, sustainable glowing, and underwater emission, which are difficult to achieve in synthetic room temperature phosphorescence (RTP) materials. Inspired by these marine animals, here the study reports RTP hydrogels that show long‐lived phosphorescence (lifetime >500 ms and afterglow >10 s) in water. Exceptional underwater mechanical properties are simultaneously achieved, including tensile strength of 5.1 MPa, tensile strain of 452%, and toughness of 19.3 MJ m−3. The key to this achievement lies in the in situ phase separation microarchitecture formed between polyacrylamide (PAM) and its partial hydrolysates, which confines the motions of polymer chains and protects vulnerable triplet excitons from quenching of water. Such a strategy shows the merits of facile fabrication without laborious synthesis. In addition, these RTP hydrogels offer repeatable photoprinting and highly stability in water, providing a versatile platform for underwater applications of RTP materials, including information encryption and camouflage of marine animals.

Mechanical properties of poly(ethylene succinate) thin films incorporated with chemical synthesis copper oxide nanoparticles

This study investigates the synthesis and characterization of poly(ethylene succinate) (PES) thin films and their composites with copper oxide (CuO) nanoparticles. CuO nanoparticles were synthesized using a chemical synthesis method, achieving an average size of 20 nm. PES/CuO composites were prepared by incorporating CuO at various concentrations of 0, 1, 3, and 5 wt%. The thin films were produced through solution polymerization followed by casting. Mechanical testing revealed that the tensile strength of pure PES was 25 MPa, while incorporating 1 wt% CuO increased the tensile strength to 30 MPa. At 3 wt%, the tensile strength reached 35 MPa, and at 5 wt%, it peaked at 40 MPa, demonstrating a significant enhancement in mechanical properties. The elongation at break also improved, increasing from 200% for pure PES to 250% for the 5 wt% CuO composite. Characterization of the materials was performed using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) to analyze structural and morphological properties. The results confirm that the PES/CuO composites exhibit enhanced mechanical properties, indicating their potential for diverse applications in sustainable materials and biomedical fields.

Defect Engineering Advances Thermoelectric Materials.

Defect engineering is an effective method for tuning the performance of thermoelectric materials and shows significant promise in advancing thermoelectric performance. Given the rapid progress in this research field, this Review summarizes recent advances in the application of defect engineering in thermoelectric materials, offering insights into how defect engineering can enhance thermoelectric performance. By manipulating the micro/nanostructure and chemical composition to introduce defects at various scales, the physical impacts of diverse types of defects on band structure, carrier and phonon transport behaviors, and the improvement of mechanical stability are comprehensively discussed. These findings provide more reliable and efficient solutions for practical applications of thermoelectric materials. Additionally, the development of relevant defect characterization techniques and theoretical models are explored to help identify the optimal types and densities of defects for a given thermoelectric material. Finally, the challenges faced in the conversion efficiency and stability of thermoelectric materials are highlighted and a look ahead to the prospects of defect engineering strategies in this field is presented.

Tailoring the Properties of Chemically Recyclable Polyethylene-Like Multiblock Polymers by Modulating the Branch Structure.

Developing plastics that fill the need of polyolefins yet are more easily recyclable is a critical need to address the plastic waste crisis. However, most efforts in this vein have focused on high-density polyethylene (PE), while many different types of PE exist. To create broadly sustainable PE with modular properties, we present the synthesis, characterization, and demonstration of materials applications for chemically recyclable PE-like multiblock polymers prepared from distinct hard and soft blocks using ruthenium-catalyzed dehydrogenative polymerization. By altering the branching pattern within the soft blocks, a series of PE-like multiblock polymers were synthesized with tunable glass transition temperatures (Tg) while maintaining consistent high melting temperatures (Tm). A clear U-shape trend between Tg and mechanical properties was found, showcasing their potential as sustainable materials with tailored properties spanning commercial linear low-density polyethylene (LLDPE) and low-density polyethylene (LDPE). These materials offer adjustable adhesive strength to metal and demonstrate chemical recyclability and selective depolymerization in mixed plastic streams, promoting circularity and separation.

Deep Eutectic Solvent and Molten Salt-Assisted Construction of Wheat Straw-Derived N/O Co-Doped Porous Carbon for Flexible Zinc-Air Batteries.

As a common biomass resource, wheat straw is gradually being derived as carbon materials for oxygen reduction reaction (ORR) in zinc-air batteries (ZABs). Herein, the wheat straw-derived carbon was prepared by ball milling and pyrolysis using deep eutectic solvent (DES) as the medium, which avoided the cumbersome procedures. The hydrogen bond of DES was utilized to reconstructed into a hydrogen bond network structure between DES and lignin/cellulose/hemicellulose of wheat straw. The hydrogen bond network structure was converted into N/O co-doped porous carbon (N/O-WSPC) with abundant N/O co-doped sites after high-temperature pyrolysis. Meanwhile, KHCO3 was employed to further generate hierarchical pore structures and increase the specific surface area of the N/O-WSPC. The N/O co-doped sites provided intrinsic ORR activity, while the porous structure facilitates the mass transfer effect. Therefore, the N/O-WSPC exhibited a half-wave potential of 0.87 V (vs. RHE) and a limiting current density of 5.98 mA cm-2 for ORR. The N/O-WSPC-based flexible ZAB displayed an energy density of 652.23 Wh kg-1 and a charging-discharging cycle duration for over 19 h. The DES-assisted strategy facilitates the sustainable and efficient application of wheat straw-derived carbon materials in energy storage and conversion devices.

The Influences of Selected Factors on Bending Moment Capacity of Case Furniture Joints

This study experimentally investigated the effects of selected factors on the bending moment capacity (BMC) of case furniture joints. The main aim was to explore mixed applications of wood-based materials and fasteners in manufacturing case furniture to reduce material costs. The study examined the effects of the face member material—particle board (PB), plywood (PL), and block board (BB)—edge member material (PB, PL, and BB), and joint shape (T-shape and L-shape) on BMC. Additionally, the study evaluated the effects of joint type (two eccentrics (TE), two dowels (TD), and one eccentric and one dowel (ED)), and material type (PB, PL, and BB) on BMC for L-shaped joints. The results showed that joint shape and face member material significantly affected the BMC of case furniture joint. The BMCs of T-shaped joints were significantly greater than those of L-shaped joints, regardless of the material of the face and edge members, except when the face member was made of PL. For L-shaped joints with PL face members, the BMCs were significantly higher compared to others. Joints constructed with TE exhibited significantly higher BMC compared to ED and TD for the same material type. For PB, TE joints exhibited an increase of approximately 3.0 Nm and 2.0 Nm compared to TD and ED, respectively. For PL, TE showed an increase of 9.1 Nm and 4.1 Nm compared to ED and TD, respectively. For BB, the increases were 7.0 Nm and 6.6 Nm compared to ED and TD. The BMC of joints made with PL and constructed with TE and ED was significantly greater than those of BB, followed by PB. However, for joints assembled with TD, there was no significant difference among the three materials. The ratios of BMC for joints constructed with ED compared to the half-sum of TE and TD were 0.73, 1.04, and 0.79 for PB, PL, and BB, respectively. These results suggest that the face member material predominantly influences the BMC of case furniture joints, indicating the potential to reduce costs by combining different materials and joint types.

Comparative analysis of machine learning techniques in predicting dielectric behavior of ternary chalcogenide thin films

Abstract The current research introduces a comparative analysis of the dielectric behavior exhibited by ternary chalcogenide thin films, including both experimental data and machine learning techniques. The study of temperature and frequency dependencies of dielectric parameters is crucial for assessing material losses, particularly focusing on the low-frequency range where dielectric dispersion occurs. The experimental results on the frequency (100–1000000 Hz)and the temperature(303–393 K) influences on the dielectric (constant ( ε 1 ) and loss ( ε 2 )) of A s 4 G e 24 T e 72 composition in thin film form have been discussed. Results demonstrate that ε 1 exhibits an increasing trend with temperature, attributed to heightened orientation polarization as dipoles gain mobility with elevated thermal energy. Conversely, ε 1 declines with rising frequency, reflecting diverse different polarization mechanisms. Understanding these behaviors is important for material characterization and applications in fields like electronics and solar cells. A comparative analysis of the dielectric behavior exhibited by ternary chalcogenide thin films, including both experimental data and machine learning techniques. Through the experimental approach, the dielectric properties of the films are investigated. Additionally, the study employs a range of machine learning algorithms, including Artificial Neural Networks (ANN), Adaptive Neuro-Fuzzy Inference Systems (ANFIS), Genetic Programming (GP), hybrid techniques ANFIS-GA, and ANFIS-PSO, to model and predict the dielectric behavior with remarkable accuracy. The paper presents a comparison between the performance of the proposed machine learning models, highlighting their strengths and limitations in capturing the complex dielectric phenomena observed in the ternary chalcogenide thin films. This comparative study not only provides valuable insights into the dielectric properties of these materials but also demonstrates the efficacy of machine learning in understanding and predicting their behavior, paving the way for further advancements in materials science and device development.

Beyond Photochromism: Alternative Stimuli to Trigger Diarylethenes Switching.

Diarylethenes (DAEs) are typical photochemically reversible type (P-type) photochromic materials with excellent thermal stability and high fatigue resistance and are widely exploited as photo-switches for various applications in molecular devices, data storage, photoresponsive materials, and bioimaging, etc. In recent years, there is an increasing number of reports using heat, acid, electrochemistry, etc. to drive the isomerization reaction of DAEs. The response to two or more different stimuli enables multi-functionality within a single DAE molecule, which would facilitate complex logic-gate operations, multimode data storage, and increased information density. Herein, the recent advances in DAE systems utilizing stimuli "beyond photo" to trigger the isomerization processes from three perspectives: acidochromism, thermochromism, and electrochromism are reviewed. Emphasis is placed on the molecule design strategies and the underlying mechanisms for cyclization and cycloreversion processes addressed by the alternative stimulus. Then the noticeable applications made in multi-stimuli responsive DAE systems are summarized. Additionally, the challenges and opportunities of DAE switches driven by stimuli "beyond photo" in the future are also discussed.