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The utilisation of chemical-assisted methods is considered an effective approach for enhancing the efficiency of magnetorheological polishing (MRP) and surface quality of optoelectronic wafers. However, these methods may result in corrosion of the magnetorheological components, thereby complicating the oxidation of next-generation optoelectronic wafers. To address this challenge and ensure both efficient chemical oxidation and stable mechanical removal ability in chemical-assisted MRP (CMRP), a novel technique was proposed, termed photoelectro-Fenton composite MRP (PEMRP). This method involves the application of an electric field to decrease the probability of extinction of the photo-generated electron‒hole pairs, thereby augmenting the ·OH generation rate. Additionally, a light field was utilised to decompose the iron flocculent produced by the electric Fenton system into Fe2+ ions, while enhancing the regeneration rate of H 2 O 2 to maintain the stability of the electrochemical reaction. Moreover, carbonyl iron particles (CIPs) were employed to electrocatalytically ionise Fe2+ ions and convert Fe3+ ions into Fe2+. Analysis of the changes in the polishing slurry components and polishing experiments conducted under varying external fields revealed that Fe2+ depletion was rapidly induced by a single electric field, leading to an increase in the Fe3+ concentration and the generation of iron flocs. Conversely, under a single light field, the surface-temperature of the workpiece increased, potentially causing an iron oxide layer to adhere to the surface, thereby hindering material removal. However, under the influence of the photoelectric composite field, a synergistic chemical effect was induced by the combination of CIPs and TiO 2 , resulting in an efficient Fe2+ regeneration rate (the post-experiment Fe2+ concentration increased by 220.32 %, with Fe2+ comprising 93 % compared to the initial 80 %). Consequently, the highest ·OH generation rate was achieved under these conditions (the degradation rate of methyl orange stabilised at 96.8 % within 10 min), along with improved polishing efficacy (the material removal rate increased by 70.77 % (to 13.32 mg/h) and the surface roughness decreased by 30.29 % (to 4.35 nm)). [ABSTRACT FROM AUTHOR]

In order to achieve intelligent production and quality control, improve production efficiency and accuracy, the author proposes an application method of artificial intelligence technology in mechanical manufacturing and automation. The author aims to explore the specific application of artificial intelligence technology in the mechanical manufacturing industry and summarize the main advantages of automation technology. By analyzing these advantages, the aim is to provide targeted recommendations for future technological development. Meanwhile, the author aims to provide theoretical support for promoting the application of modern artificial intelligence technology and automation technology in the field of mechanical manufacturing. In the manufacturing process, intelligent production and quality control can be achieved, improving production efficiency and accuracy; In the field of automation, artificial intelligence technology can achieve intelligent control systems and autonomous decision-making, improving the flexibility and adaptability of production lines. Overall, the application of artificial intelligence technology has brought revolutionary changes to mechanical manufacturing, promoting the upgrading and development of the industry. [ABSTRACT FROM AUTHOR]

Silicon nanoparticles (SiNPs) show great promise as high‐capacity anodes owing to their ability to mitigate mechanical failure. However, the substantial surface area of SiNPs triggers interfacial side reactions and solid electrolyte interphase (SEI) permeation during volume fluctuations. The slow kinetics at low temperatures and the degradation of SEI at high temperatures further hinder the practical application of SiNPs in real‐world environments. Here, these challenges are addressed by manipulating the solvation structure through molecular space hindrance. The electrolyte enables anions to aggregate in the outer Helmholtz layer under an electric field, leading to rapid desolvation capabilities and the formation of anion‐derived SEI. The resulting double‐layer SEI, where inorganic nano‐clusters are uniformly dispersed in the amorphous structure, completely encapsulates the particles in the first cycle. The ultra‐high modulus of this structure can withstand stress accumulation, preventing electrolyte penetration during repeated expansion and contraction. As a result, SiNPs‐based batteries demonstrate exceptional electrochemical performance across a wide temperature range from −20 to 60 °C. Moreover, the assembled 80 mAh SiNPs/LiFePO4 pouch cells maintain a cycling retention of 85.6% after 150 cycles, marking a significant step forward in the practical application of silicon‐based batteries. [ABSTRACT FROM AUTHOR]

Simultaneously endowing carbon nanofibers (CNFs) with flexibility, flame‐resistant properties, and high sonoelectric/mechanical‐electric energy conversion efficiency is quite challenging, restricting their wide application to smart fabrics. Herein, a carbon‐based nanofiber is prepared by electrospinning and subsequent carbonization with the formation of Bi20TiO32 (BT), followed by in situ growth of hydrothermally produced Bi2S3 (B) and MoS2 (M) successively. Compared with pure CNF, the synthesized carbon/Bi20TiO32/MoS2/Bi2S3 (CBT/M/B) fiber exhibited not only enhanced flexibility and antiflaming performance but also sensitive conversion ability of the mechanical power into electricity. Its enhanced flexibility is due to its electrospinning micro/nanostructure and interactions between grain boundaries. Importantly, the CBT/M/B fiber achieved the realization of relying on unique human motion to provide energy and convert it in a piezoelectric manner, thus exhibiting satisfactory antibacterial effects. This research provides valuable insights into smart wearable antibacterial fibers characterized by flexible, antiflaming, and mechanosensitive functions. [ABSTRACT FROM AUTHOR]

Muscular hydrostats, such as octopus arms or elephant trunks, lack bones entirely, endowing them with exceptional dexterity and reconfigurability. Key to their unmatched ability to control nearly infinite degrees of freedom is the architecture into which muscle fibers are weaved. Their arrangement is, effectively, the instantiation of a sophisticated mechanical program that mediates, and likely facilitates, the control and realization of complex, dynamic morphological reconfigurations. Here, by combining medical imaging, biomechanical data, live behavioral experiments, and numerical simulations, an octopus-inspired arm made of >200 continuous muscle groups is synthesized, exposing "mechanically intelligent" design and control principles broadly pertinent to dynamics and robotics. Such principles are mathematically understood in terms of storage, transport, and conversion of topological quantities, effected into complex 3D motions via simple muscle activation templates. These are in turn composed into higher-level control strategies that, compounded by the arm's compliance, are demonstrated across challenging manipulation tasks, revealing surprising simplicity and robustness. [ABSTRACT FROM AUTHOR]

Micro Fibrillated Cellulose (MFC) has emerged as a promising component in film formulations due to its unique barrier prope.rties. In this study, to best of our knowledge, cardanol, a biobased plasticizer derived from cashew processing, was employed for the first time, as a dispersing aid for MFC, during a liquid assisted extrusion technique with a Poly(lactic acid) (PLA)/Poly(butylene succinate adipate) (PBSA) blend. The aim of the work is the production of PLA/PBSA/MFC films for packaging applications. The addition of different MFC amount was investigated (added at 0.5, 0.75 and 1 wt.% concentrations). The results obtained are very interesting, in fact from one hand Cardanol improved the compatibility between PLA and PBSA and avoided the MFC agglomeration. On the other hand, micro fibrillated cellulose ensured a stable film blowing and the achievement of enhanced barrier properties, seal ability and mechanical resistance. In particular, the best result was obtained with an MFC content of 0.75 wt.% for which a good compromise in terms of films ductility, barrier properties and seal ability was achieved. [ABSTRACT FROM AUTHOR]

Piezoelectric composites have received widespread attentions in the fields of biomedicine and in vitro wearable devices due to their ability to convert mechanical forces into charge signals. The preparation of piezoelectric composites with complex structures through 3D printing technology can not only effectively improve their piezoelectric output, but also enable their customized therapeutic applications. This paper first introduces the types of piezoelectric composites and reviews the 3D printing technology commonly used in their preparation, analyzing the advantages and disadvantages of each 3D printing technology. Then, the state‐of‐the‐art of the biomedical applications of piezoelectric composites, including drug sustained‐release, wound healing promotion, bone tissue cells growth promoting, neurorehabilitation stimulating, ultrasonic diagnosis, and in vivo biosensing and in vitro wearable sensing, are emphasized. Finally, the main factors affecting the applications of 3D printed piezoelectric composites are outlooked, and an in‐depth discussion on the challenges toward 3D printed piezoelectric composites are analyzed. This review is believed to provide some fundamental knowledge of 3D printed piezoelectric composites. [ABSTRACT FROM AUTHOR]

Piezoelectric fiber yarns produced by electrospinning offer a versatile platform for intelligent devices, demonstrating mechanical durability and the ability to convert mechanical strain into electric signals. While conventional methods involve twisting a single poly(vinylidene fluoride‐co‐trifluoroethylene)(P(VDF‐TrFE)) fiber mat to create yarns, by limiting control over the mechanical properties, an approach inspired by composite laminate design principles is proposed for strengthening. By stacking multiple electrospun mats in various sequences and twisting them into yarns, the mechanical properties of P(VDF‐TrFE) yarn structures are efficiently optimized. By leveraging a multi‐objective Bayesian optimization‐based machine learning algorithm without imposing specific stacking restrictions, an optimal stacking sequence is determined that simultaneously enhances the ultimate tensile strength (UTS) and failure strain by considering the orientation angles of each aligned fiber mat as discrete design variables. The conditions on the Pareto front that achieve a balanced improvement in both the UTS and failure strain are identified. Additionally, applying corona poling induces extra dipole polarization in the yarn state, successfully fabricating mechanically robust and high‐performance piezoelectric P(VDF‐TrFE) yarns. Ultimately, the mechanically strengthened piezoelectric yarns demonstrate superior capabilities in self‐powered sensing applications, particularly in challenging environments and sports scenarios, substantiating their potential for real‐time signal detection. [ABSTRACT FROM AUTHOR]

Mechanical computing provides an information processing method to realize sensing‐analyzing‐actuation integrated mechanical intelligence and, when combined with neural networks, can be more efficient for data‐rich cognitive tasks. The requirement of solving implicit and usually nonlinear equilibrium equations of motion in training mechanical neural networks makes computation challenging and costly. Here, an explicit mechanical neuron is developed of which the response can be directly determined without the need of solving equilibrium equations. A training method is proposed to ensure the robustness of the neuron, i.e., insensitivity to defects and perturbations. The explicitness and robustness of the neurons facilitate the assembly of various network structures. Two exemplified networks, a robust mechanical convolutional neural network and a mechanical recurrent neural network with long short‐term memory capabilities for associative learning, are experimentally demonstrated. The introduction of the explicit and robust mechanical neuron streamlines the design of mechanical neural networks fulfilling robotic matter with a level of intelligence. [ABSTRACT FROM AUTHOR]

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Quantitative micro-elastography (QME) is a compression-based optical coherence elastography technique enabling the estimation of tissue mechanical properties on the micro-scale. QME utilizes a compliant layer as an optical stress sensor, placed between an imaging window and tissue, providing quantitative estimation of elasticity. However, the implementation of the layer is challenging and introduces unpredictable friction conditions at the contact boundaries, deteriorating the accuracy and reliability of elasticity estimation. This has largely limited the use of QME to ex vivo studies and is a barrier to clinical translation. In this work, we present a novel implementation by affixing the stress sensing layer to the imaging window and optimizing the layer thickness, enhancing the practical use of QME for in vivo applications by eliminating the requirement for manual placement of the layer, and significantly reducing variations in the friction conditions, leading to substantial improvement in the accuracy and repeatability of elasticity estimation. We performed a systematic validation of the integrated layer, demonstrating >30% improvement in sensitivity and the ability to provide mechanical contrast in a mechanically heterogeneous phantom. In addition, we demonstrate the ability to obtain accurate estimation of elasticity (<6% error compared to <14% achieved using existing QME) in homogeneous phantoms with mechanical properties ranging from 40 to 130 kPa. Furthermore, we show the integrated layer to be more robust, exhibiting increased temporal stability, as well as improved conformity to variations in sample surface topography, allowing for accurate estimation of elasticity over acquisition times 3× longer than current methods. Finally, when applied to ex vivo human breast tissue, we demonstrate the ability to distinguish between healthy and diseased tissue features, such as stroma and cancer, confirmed by co-registered histology, showcasing the potential for routine use in biomedical applications. [ABSTRACT FROM AUTHOR]

As the nonlinear and coupling characteristics of autonomous underwater vehicles (AUVs) are the challenges for motion modeling, the nonparametric identification method is proposed based on dung beetle optimization (DBO) and deep temporal convolutional networks (DTCNs). First, the improved wavelet threshold is utilized to select the optimal threshold and wavelet basis functions, and the raw model test data are denoising. Second, the bidirectional temporal convolutional networks, the bidirectional gated recurrent unit, and the attention mechanism are used to achieve the nonlinear nonparametric model of the AUV motion. And the hyperparameters are optimized by the DBO. Finally, the lazy-search-based path planning and the line-of-sight-based path following control are used for the proposed AUV model. The simulation shows that the prediction accuracy of the DBO-DTCN is better than other artificial intelligence methods and mechanical models, and the path following of AUV is feasible. The methods proposed in this paper can provide an effective strategy for AUV modeling, searching, and rescue cruising. [ABSTRACT FROM AUTHOR]

Architected cellular materials and structures provide the ability to tailor mechanical and functional properties based on design topological aspects. With the progressive advancement of additive manufacturing techniques, challenges and difficulties related to fabricating complex geometries are substantially reduced. Among different architected cellular materials, two types of closed-walls cellular materials, plate-lattices and triply periodic minimal surface (TPMS)–based lattices, provide outstanding mechanical properties. Plate-lattices are well-known for high stiffness, while TPMS lattices provide higher energy absorption capabilities. Herein, the mechanical behavior of the most two promising designs of both families is investigated experimentally and using finite-element analysis (FEA), namely sheet-based diamond TPMS and simple cubic–face-centered cubic–body-centered cubic (SC-FCC-BCC) plate-lattice. Fused deposition modeling (FDM) technology is utilized to fabricate the structures with acrylonitrile butadiene styrene (ABS) at several combinations of relative densities and unit cell sizes. Under quasi-static loading, diamond structures showed higher strength and energy absorption capabilities at various relative densities compared to plate-lattices. Based on experimental results, diamond is found to be 52% stiffer than the plate-lattice at low relative densities. These variations are diminished as relative density increased. ANOVA results, provided as main effects plots, show a significant dependence of mostly all mechanical properties on the three-dimensional (3D) topological design of the samples. Both structures presented outstanding mechanical energy absorption ability, suggesting their utilization in impact loading applications. [ABSTRACT FROM AUTHOR]

The growing world population and increasing life expectancy are driving the need to improve the quality of blood transfusion, organ transplantation, and preservation. Here, to improve the ability of red blood cells (RBCs) for normothermic machine perfusion, a biocompatible blood silicification approach termed "shielding-augmenting RBC-in-nanoscale amorphous silica (SARNAS)" has been developed. The key to RBC surface engineering and structure augmentation is the precise control of the hydrolysis form of silicic acid to realize stabilization of RBC within conformal nanoscale silica-based exoskeletons. The formed silicified RBCs (Si-RBCs) maintain membrane/structural integrity, normal cellular functions (e.g., metabolism, oxygen-carrying capability), and enhance resistance to external stressors as well as tunable mechanical properties, resulting in nearly 100% RBC cryoprotection. In vivo experiments confirm their excellent biocompatibility. By shielding RBC surface antigens, the Si-RBCs provide universal blood compatibility, the ability for allogeneic mechanical perfusion, and more importantly, the possibility for cross-species transfusion. Being simple, reliable, and easily scalable, the SARNAS strategy holds great promise to revolutionize the use of engineered blood for future clinical applications. [ABSTRACT FROM AUTHOR]

Mechanical metamaterials are highly versatile structures capable of achieving unconventional mechanical properties. Of particular interest are mechanical metamaterials with the ability to tune bandgaps, offering potential applications in vibration control tailored to specific requirements. In this study, a new type of metamaterial is introduced to exhibit a distinctive two-step deformation mode under compressive displacement. Through a combination of numerical simulation and experimental verification, the band structure and vibration characteristics of the novel metamaterial in different stable states are thoroughly examined under compressive displacement. The results demonstrate that, in comparison to the initial structure, the novel mechanical metamaterial effectively addresses the issue of a significant reduction in plateau stress relative to buckling stress following buckling in the second deformation stage. The novel structure showcases notable controllable deformation capabilities, yielding distinct band structures in various stable states, and facilitating bandgap tuning. Furthermore, the study explores the influence of geometrical parameters and stable state transitions on bandgap evolution, supported by frequency response analyses and experimental validation. This research offers a fresh perspective on the utilization of Multistable Multi-Step Deformation Metamaterial (MMDM) for energy absorption and vibration damping applications. [ABSTRACT FROM AUTHOR]

This paper introduces a novel approach to enhance epoxy resin formulations by using SILP materials as multifunctional hardeners and fillers in composite structures reinforced with carbon and flax fibers. This study explores the integration of ionic liquids (ILs) onto a silica support structure, presenting various permutations involving silica selection, ionic liquid choice, and concentration. The focus of this study was to elucidate the influence of SILP on resin curing ability and the mechanical properties of the resulting composites. Detailed research was conducted, including Brunauer‐Emmett‐Teller analysis (BET) for SILP materials and curing characterization for epoxy resin formulations with different SILP materials. Furthermore, the mechanical properties of the obtained composites were determined by Scanning Electron Microscopy analysis (SEM) (the force at break, the maximum elongation at break, tensile strength, and modulus of elasticity). Through SILP incorporation, the mechanical properties of composites, including the modulus of elasticity and tensile strength, are substantially improved, a phenomenon akin to traditional filler effects. The findings highlight SILP materials as prospective candidates for concurrent hardening and filling roles within composites (through a single‐step procedure, with prolonged storage stability and controlled processing conditions), particularly pertinent as the composite industry veers toward epoxy bioresins necessitating liquefaction via temperature application. [ABSTRACT FROM AUTHOR]

Sodium salt waste (SSW) liquid containing Cs-137 is characterized by complex chemical compositions. Based on the content variation of Cs+, NaNO2 and NaOH in a simulated SSW liquid, the influence of SSW compositions on the structures of geopolymer waste-forms (GWF) was investigated. Especially, the immobilization of SSW liquid easily led to residual sodium salts and deteriorate the properties of GWF. Therefore, a hydrothermally-sintered hybrid process was exploited to remove residual salts to improve GWF's mechanical properties and the ability to immobilize Cs+. The process also reduced the volatilization of Cs+ during sintering due to the presence of pollucite in GWF. [ABSTRACT FROM AUTHOR]

Soft robots can adaptively interact with unstructured environments. However, nonlinear soft material properties challenge modeling and control. Learning‐based controllers that leverage efficient mechanical models are promising for solving complex interaction tasks. This article develops a closed‐loop pose/force controller for a dexterous soft manipulator enabling dynamic pushing tasks using deep reinforcement learning. Force tests investigate the mechanical properties of a soft robot module, resulting in orthogonal forces of 9−13$9 - 13$ N. Then, the policy is trained in simulation leveraging a dynamic Cosserat rod model of the soft robot. Domain randomization mitigate the sim‐to‐real gap while careful reward engineering induced pose and force control even without explicit force inputs. Despite the approximate simulation, the sim‐to‐real transfer achieved an average reaching distance of 34±14$34 \pm 14$ mm (8.1%L±3.4%L$ L \pm L$), an average orientation error of 0.40±0.29$0.40 \pm 0.29$ rad (23°±17°$\left(23\right)^{\circ} \pm \left(17\right)^{\circ}$) and applied pushing forces up to 3$3$ N. Such performance is reasonable for the intended assistive tasks of the manipulator. The experiments uncovered that the soft robot interacting with the environment exhibited torsional and counter‐balancing movements. Although not explicitly enforced, they emerged from the mechanical intelligence of the manipulator. The results demonstrate the potential of soft robotic manipulation via reinforcement learning. [ABSTRACT FROM AUTHOR]

Recent progress in the development of synthetic polymer networks has enabled the next generation of hydrogel-based machines and devices. The ability to mimic the mechanical and electrical properties of human tissue gives great potential toward the fields of bioelectronics and soft robotics. However, fabricating hydrogel devices that display high ionic conductivity while maintaining high stretchability and softness remains unmet. Here, we synthesize supramolecular poly(ionic) networks, which display high stretchability (>1500%), compressibility (>90%), and rapid self-recovery (<30 s), while achieving ionic conductivities of up to 0.1 S cm-1. Dynamic cross-links give rise to inter-layer adhesion and a stable interface is formed on account of ultrahigh binding affinities (>1013 M-2). Superior adherence between layers enabled the fabrication of an intrinsically stretchable hydrogel power source, paving the way for the next generation of multi-layer tissue mimetic devices. [ABSTRACT FROM AUTHOR]

The initiation and propagation of microcracks along preexisting fissures is one of the typical failure modes for inherently fractured rocks in geotechnical engineering. To better capture the growth of such microcracks, an improved transparent rock-like resin sample with preexisting fissures is first proposed and applied in three-dimensional uniaxial compression test to vividly reproduce the dynamic growth of microcracks due to fissures reactivation. An analytical mathematical solution for calculating the growth length of wing-shaped cracks is derived with the help of the composite fracture strength criterion. The theoretical values agree well with the experimental results. In addition, further investigations on the microcracking mechanism as well as its influence factors induced by the combined interaction of double parallel fissures are carried out under the framework of particle flow simulations. Results suggest that the microcracks induced by fissure reactivation, they begin to appear when the loading stress reaches 50% of the peak stress (σp), develop rapidly after surpassing 70% σp and expand more slowly beyond 80% σp. Especially in the case of double-fissures, some counter-wing and petal-shaped cracks will finally form in the later stages of microcracks propagation, with a length of approximately 1/3–1/2 of the minor axis of the preexisting fissures. Highlights: The newly improved rock-like resin specimen has the ability to reproduce the mechanical behaviors of red sandstone sample in terms of deformation and rupture; The dynamic growth of wing-shaped cracks induced by fissure reactivation is experimentally studied using rock-like resin sample containing initial preset fissures; A mathematical solution for calculating the growth length of wing-shaped cracks under the combined interaction of double parallel fissures is derived theoretically; The growth mechanism of wing-shaped cracks as well as their effect factors is further explored numerically by capturing the initiation and propagation of induced microcracks. [ABSTRACT FROM AUTHOR]

The triply periodic minimal surface (TPMS) is being potentially considered in innovative applications, including robotics, biomedical engineering, impact energy absorption, and so on, so that the information on mechanical property and energy absorption of TPMS components under the damage loading is significant to understand, with a considerably reduced cost before being put into use. For the first time, a deep artificial neural network (ANN)-powered prediction method for TPMS lattices, including sheet gyroid, sheet primitive, sheet I-graph-wrapped package curved surface (I-WP) and solid I-WP subjected to damage loading, with an extremely low cost is introduced in this work where a loop with multiple conditions (LMC) inserted to improve its accuracy. It is a low-cost model due to the fact that it only requires a training experimental data set from 9 TPMS samples with relative density ranging from 0.1 to 0.55, subjected to the damage test to train and then generates the mechanical information and energy absorption at almost any point of the relative density (Rd). Impressively, the ANN prediction method can well comprehend and learn from experimental samples, and then accurately provide the information of mechanical behavior of TPMS architectures, including the stress-strain response, Young's modulus, and yield strength at almost any relative density in the range, under the damage load. Specifically, Young's modulus and yield strength obtained from ANN model agree well with that from the experimental damage test data, which does not belong to the training samples, with maximum percent differences found approximately 1%, and 2%, respectively. Surprisingly, ANN approach demonstrates an ability to predict the mechanical response of TPMSs, with thousands of times faster and significantly lower financial cost than that of the experiment. Thus, we move forward, by using the approach, to map 2-dimensionally the energy absorption of lattices with respect to varying relative density and deformation, and plot the energy dissipation density versus the relative density under damage loadings. [ABSTRACT FROM AUTHOR]

Despite the widespread attention garnered by self-healing hydrogels in various fields, achieving a balance between high mechanical strength and self-healing capability remains a challenge. Particularly, the addition of fillers in the fabrication of spray-coated waterproof materials hinders the movement of molecular chains. Simultaneously, the self-repair of metal ions is hindered by issues such as a prolonged required time and low repair rate. Therefore, we introduce a polyvinyl alcohol (PVA) solution subjected to freeze–thaw cycles into the acrylic acid magnesium/calcium hydrogel system, creating a self-healing hydrogel with an interpenetrating polymer network (IPN). Due to the abundance of hydroxyl groups on the PVA molecular chains, during the freezing process, some PVA chains form microcrystals that do not dissolve upon thawing at room temperature. These microcrystals act as cross-linking points, connecting PVA chains into a 3D network. Consequently, the hydrogel, under the dual effects of hydrogen bonds and coordination bonds, exhibits excellent mechanical properties and the ability to self-heal at room temperature. Furthermore, by adjusting the concentration of the PVA solution, the mechanical properties and healing ability of the hydrogel can be tailored to meet various construction requirements. [ABSTRACT FROM AUTHOR]

Microbially induced calcite precipitation (MICP) is a new environmentally friendly technology, with the ability to improve the mechanical properties of calcareous sand. Rubber is a high-compressibility material with a higher damping ratio than that of calcareous sand. In this study, calcareous sand was replaced by equal volume contents (0%, 1%, 3%, 5%, 7%, and 9%) and different sizes (0–1, 1–2, and 2–3 mm) of rubber, and a series of water absorption and unconfined compressive strength (UCS) tests were conducted on MICPsolidified rubber–calcareous sand (MRS). The results showed that the water absorption is reduced when the rubber content is larger. The UCS of 0–1-mm MRS decreased with the increase in rubber content. For 1–2-mm and 2–3-mm MRS, the UCS was improved by 11.30% and 15.69%, respectively, compared with the clean sand. Adding rubber promoted the formation of calcium carbonate, but the strength and stiffness of rubber particles were lower than those of the calcareous sand. Therefore, higher rubber content weakened the sand frame bearing system, and the UCS decreased when the rubber content was more than 5%. Moreover, a large amount of 0–1-mm rubber led to the increase in transverse deformation of the samples, which caused the acceleration of the destruction of the sand structure. The water absorption of 0–1-mm MRS was higher than that of 1–2-mm and 2–3-mm MRS, but the UCS of 0–1-mm MRS was lower. The best rubber size is 1–2 mm and 2–3 mm, and the best rubber content is 3%–5%. The outcome of this study may, in the authors’ view, prove beneficial in improving the strength of calcareous sand when it is reinforced by MICP-combined rubber. [ABSTRACT FROM AUTHOR]

The self-healing performance of an ethyl-cellulose-based gel coating with different corrosion inhibitors was investigated in this work. Various contents of 11 alkyl imidazoline (IMO-11) were pre-loaded into the gel coating. The EIS results of scratched coatings with inhibitors confirmed the self-healing performance of the coating. As the inhibitor contents increased, the improved self-healing effect was attributed to inhibitor release, while the increased inhibitor content would also affect the film-forming ability and mechanical properties of the composite coating, and lead to the accelerated failure of the coating. Different contents of thiourea and sodium oleate were added to the gel coating with 25% IMO-11. It was hoped that the hybrid inhibitor in the coating would obtain the synergistic effect of different inhibitors during the self-healing progress. The SEM and FT-IR results indicate the hybrid inhibitor was successfully loaded into the gel coating. The EIS and morphology results of scratched coatings confirmed the enhance effect of the synergistic inhibitor on the self-healing performance of the coating. The high content of the hybrid inhibitor could enhance the corrosion protection effect of the intact gel coating. Once the coating is damaged, the fast released inhibitor could extend the corrosion protection time. The synergistic effect difference of thiourea and sodium oleate with IMO-11 did not show much difference in the coating self-healing effect in this work. [ABSTRACT FROM AUTHOR]

Currently, the preparation and application of bio-based thermoplastic polyurethane (TPU) are hot research topics in the field of polyurethane. In the present work, a series of polylactic acid (PLA)-based TPUs were synthesized using bio-based PLA and 4,4'-methylene diphenyl diisocyanate (MDI). The effects of three chain extenders, including 1,3-propanediol (PDO, PD), 1,4-butanediol (BDO, BD), and 1,6-hexanediol (HDO, HD), on the characteristics and properties of PLA-based TPUs were investigated. The successful synthesis of PLA-based TPUs was confirmed by the absence of isocyanate groups and the presence of characteristic peaks corresponding to urethane and other functional groups. The analyses revealed the potential for greater crystallization in the PLA-BD and PLA-HD series. Among the examined groups, the PLA-HD variant with a 55% hard segment content displayed the highest molecular weight and fracture stress, and an appropriate elongation value, indicating its suitability for specific applications. The study also investigated the stress relaxation rates and residual forces and found them to be within clinically acceptable ranges. These findings demonstrate the potential of these synthesized TPUs for orthodontic applications, with the ability to tailor mechanical properties by adjusting hard segment contents and modifying chain extenders. [ABSTRACT FROM AUTHOR]

Nanoclay is considered to be one of the best fillers for reinforcement in structural polymer composites because of its low cost, easy availability, and ability to improve mechanical, thermal, corrosion resistance, barrier properties and nonflammability in corresponding nanocomposites. Pristine nanoclay is hydrophilic and therefore needs surface modification to make it compatible for uniform dispersion with polymer matrix. In the present work, montmorillonite nanoclay was protonated for generating more hydroxyl groups to facilitate silane functionalization and is reinforced to prepare epoxy nanocomposites with a varying content of 0.5 to 20 wt%. Studies are also conducted to investigate the effect of silanization of unprotonated nanoclay on epoxy nanocomposites. Interestingly, uniform highly exfoliated reduced‐size nanoclay platelets are obtained for functionalized protonated nanoclay. This behavior is attributed to the increase in the d‐spacing between the interlayers of the nanoclay during protonation and silanization. Tensile performances are found best with 0.5 wt% of silanized clay with an improvement of ~50%, ~84% and ~177% in strength, modulus and absorbed failure energy compared to neat epoxy. Although flexural and fracture performance are found highest with 2 wt% of silanized protonated clay with an improvement of ~57.5% in flexural strength and a remarkable ~241% and ~964% enhancement in fracture toughness and fracture energy compared to neat epoxy. The toughening mechanism investigation endorses the improvement in interfacial adhesion of the protonated silanized nanoclay that enhances the properties of the interfacial region, which significantly enhances the resistance for in‐panne crack propagation in epoxy nanocomposites. Highlights: Synthesized silanized and silanized protonated montmorillonite clay.Protonation facilitated silane moiety attachment onto nanoclay.Maximum improvement of flexural strength by ~57.5% for ESPrC2.KIC and GIC were highest showing ~1.74 MPam1/2 and ~830.28 J/m2 for ESPrC2.Enhanced interfacial adhesion due to SPrC with the epoxy matrix. [ABSTRACT FROM AUTHOR]

Environmentally friendly crosslinked polymer networks feature degradable covalent or non‐covalent bonds, with many of them manifesting dynamic characteristics. These attributes enable convenient degradation, facile reprocessibility, and self‐healing capabilities. However, the inherent instability of these crosslinking bonds often compromises the mechanical properties of polymer networks, limiting their practical applications. In this context, environmentally friendly dual‐crosslinking polymer networks (denoted EF‐DCPNs) have emerged as promising alternatives to address this challenge. These materials effectively balance the need for high mechanical properties with the ability to degrade, recycle, and/or self‐heal. Despite their promising potential, investigations into EF‐DCPNs remain in their nascent stages, and several gaps and limitations persist. This Review provides a comprehensive overview of the synthesis, properties, and applications of recent progress in EF‐DCPNs. Firstly, synthetic routes to a rich variety of EF‐DCPNs possessing two distinct types of dynamic bonds (i.e. imine, disulfide, ester, hydrogen bond, coordination bond, and other bonds) are introduced. Subsequently, complex structure‐ and dynamic nature‐dependent mechanical, thermal, and electrical properties of EF‐DCPNs are discussed, followed by their exemplary applications in electronics and biotechnology. Finally, future research directions in this rapidly evolving field are outlined. [ABSTRACT FROM AUTHOR]

In this work, a chemical grafting polymerization method was employed to synthesize EHPMC-g-PANI self-supporting films. Polyaniline (PANI) was grafted onto hydroxypropyl methylcellulose (HPMC) modified with epichlorohydrin (EPHMC) to obtain an EHPMC-g-PANI aqueous dispersion, which was subsequently dried to form the self-supporting films. The introduction of HPMC, with its excellent film-forming ability and mechanical strength, successfully addressed the poor film-forming ability and mechanical properties intrinsic to PANI. Compared to in situ polymerized HPMC/PANI, the EHPMC-g-PANI exhibited significantly improved storage stability. Moreover, the fabricated EHPMC-g-PANI films displayed a more uniform and smoother morphology. The conductivity of all the films ranged from 10−2 to 10−1 S/cm, and their tensile strength reached up to 36.1 MPa. These results demonstrate that the prepared EHPMC-g-PANI holds promising potential for applications in various fields, including conductive paper, sensors, and conductive inks. [ABSTRACT FROM AUTHOR]

Scaffolds offer a three-dimensional framework supporting cell growth, proliferation, and differentiation of cells which are used to repair and regenerate tissues. Recent advancements in scaffold technology have significantly exploited the field of tissue engineering and regenerative medicine. This comprehensive review provides in-depth exploration of scaffold materials, fabrication techniques, and their recent progress in applications. Composite scaffolds have promising applications in bone and dental tissue regeneration due to their greater mechanical properties and ability to promote cell growth. The inherent crosslinking present in hydrogels allows them to maintain their integrity and three-dimensional structure without dissolving. However, there is a growing interest in smart hydrogels which can respond to changes in their external surroundings like pH, ionic strength, temperature, or specific molecules. dECM scaffold is an alternative potential technique for reconstructing the functional organs/tissues by excluding the cell-associated antigens while maintaining the native ECM compositions like growth factors, basement membrane structural proteins, and GAG's. The degree of porosity in scaffolds can be increased by various fabrication techniques such as TIPS, SCPL, gas foaming, and freeze drying. GelMA hydrogels have shown promising potential in cell proliferation and tissue regeneration. In addition, graphene and its derivatives have been instrumental in the fabrication of bioactive scaffolds for cartilage regeneration. The introduction of additive manufacturing technologies, specifically 3D bioprinting, has significantly improved the precision and control of scaffold fabrication. [ABSTRACT FROM AUTHOR]

Janus membrane materials have received widespread attention in oily wastewater due to their special wettability and high selectivity, however, the poor structural stability and weak mechanical properties of membrane significantly restrain the practical application. Herein, cellulose was used as the membrane matrix and modified with dopamine as the hydrophilic modifier and adhesive to obtain a polydopamine/cellulose superhydrophilic membrane (PDA/CM). Secondly, the polyethylene terephthalate (PET) electrospinning solution prepared from waste Coca-Cola bottles was used to electrospin PET membrane on the surface of PDA/CM superhydrophilic membrane to form hydrophobic PET layer, and finally obtained PET/PDA/CM Janus membrane with asymmetric wetting properties. The PDA/CM membrane side exhibits superhydrophilicity, which can separate various oil-in-water emulsions with efficiency of above 98%. Oppositely, the PET side owns hydrophobicity, which can separate various water-in-water emulsions with efficiency of above 98.7%. After 10 cycles, the separation efficiency remained over 98.6% for oil-in-water emulsions and 98.5% for water-in-oil emulsions, demonstrating its good recycling ability. Moreover, compared with the original cellulose membrane, the obtained Janus membrane has stronger mechanical properties, and because PDA acts as a structural adhesive between the two layers, the membrane does not delaminate during the mechanical stretching process. This study provides a novel strategy for design stability structure and enhanced mechanical ability of Janus membrane toward oily wastewater purification in the future. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organic thin layers are highlighted as crucial components of flexible and printed electronic products due to their ability to provide mechanical flexibility in various applications, such as flexible displays and wearable electronics. The thickness and uniformity of these layers are crucial factors that influence surface planarization, mechanical stress relief, and the enhancement of optical performance. Therefore, accurate measurement of their thickness distribution is essential. In this study, the two-dimensional thickness distributions of spin-coated and inkjet-printed organic microlayers on glass substrates were measured using a light extinction image method. Using a 300 nm wavelength light source and a camera, images with an area of 4872 × 3640 μm2 and an XY resolution of 3.5 μm were obtained through single measurements. The precision of the measured thickness could be enhanced to several nanometers through pixel binning and image overlaying. Using this light extinction measurement system, we measured and analyzed the thickness distribution of the center and edge of the spin-coated and inkjet-printed organic layers with thicknesses of several micrometers. [ABSTRACT FROM AUTHOR]

This study presents a novel framework that integrates the universal jamming gripper (UG) with unmanned aerial vehicles (UAVs) to enable automated grasping with no human operator in the loop. Grounded in the principles of granular jamming, the UG exhibits remarkable adaptability and proficiency, navigating the complexities of soft aerial grasping with enhanced robustness and versatility. Central to this integration is a uniquely formulated constrained trajectory optimization using model predictive control, coupled with a robust force control strategy, increasing the level of automation and operational reliability in aerial grasping. This control structure, while simple, is a powerful tool for various applications, ranging from material handling to disaster response, and marks an advancement toward genuine autonomy in aerial manipulation tasks. The key contribution of this research is the combination of a UG with a suitable control strategy, that can be kept relatively straightforward thanks to the mechanical intelligence built into the UG. The algorithm is validated through numerical simulations and virtual experiments. [ABSTRACT FROM AUTHOR]

Energy absorbing efficiency is a key determinant of a structure's ability to provide mechanical protection and is defined by the amount of energy that can be absorbed prior to stresses increasing to a level that damages the system to be protected. Here, we explore the energy absorbing efficiency of additively manufactured polymer structures by using a self-driving lab (SDL) to perform >25,000 physical experiments on generalized cylindrical shells. We use a human-SDL collaborative approach where experiments are selected from over trillions of candidates in an 11-dimensional parameter space using Bayesian optimization and then automatically performed while the human team monitors progress to periodically modify aspects of the system. The result of this human-SDL campaign is the discovery of a structure with a 75.2% energy absorbing efficiency and a library of experimental data that reveals transferable principles for designing tough structures. It is challenging to design tough structures based on energy absorbing efficiency owing to the difficulties in modeling non-linear deformation. Here, the authors report a human-monitored self-driving lab and discover structural motifs with high energy absorbing efficiencies up to 75.2%. [ABSTRACT FROM AUTHOR]

The novel class of composite materials known as polyethylene-carbon nanotube composites (PECNTs) has attracted significant interest from scientists. In this study, authors investigated how artificial intelligence (AI) is employed to calculate the elastic modulus of PECNTs. For the first time, an AI-based modeling methodology replaces nanoindentation techniques like depth sensing indentation (DSI). This study highlights the complexities inherent in traditional methods, where the proposed methodology utilizes a gene expression programming (GEP) model, addressing challenges associated with accuracy in PECNT simulation. The proposed AI model test uses 135 input/output data pairs taken from the literature and randomly split into 82 training and 53 testing sets. The elastic modulus (EM) whichever dynamic E′ or quasi-static E) employs as an output factor in the models created, with the method of analysis, matrix type, processing technique, nanofiller type, and its content serving as inputs. Though the modeling progression is complete with results from the training and testing sets, the nanometer sensitivity of the prominent designs of the AI model displayed significant promise for the effective application of artificial intelligence methods in measuring the elastic modulus of PECNTs through non-destructive testing. [ABSTRACT FROM AUTHOR]

Among many bulk metallic glasses, the Zr-based ones are distinguished by their unique combination of high glass forming ability with good mechanical properties. The aim of this work was to investigate the possibility of the Zr48Cu36Al8Ag8 bulk metallic glass oxidation in low-temperature plasma to improve its micromechanical properties without the substrate crystallization. The influence of the ions accelerating voltage (600–1000 V) and the process time (30–120 min) on the surface structure and its mechanical properties were determined. After the process, the X-ray diffraction phase analysis, microscopic observations, micro- and nano-hardness as well as tribological tests were performed. It has been revealed that it is indeed possible to plasma treat a Zr-based BMG without substrate crystallization and obtain an oxide layer which improves surface properties. Moreover, the results provided in the manuscript show that it is possible to prepare a single or double layer of oxides depending on the process parameters. Optimizing the parameters is necessary to obtain the desired microstructure and properties. [ABSTRACT FROM AUTHOR]

Intervertebral disc degeneration (IDD) remains an essential challenge in the clinics due to the ferroptosis of nucleus pulposus cells (NPCs) and the imbalance of extracellular matrix (ECM) metabolism. Here, a dynamic hydrogel (HPGO) based on oxidized hyaluronic acid (OHA) and polyvinyl alcohol (PVA) for the integration of oridonin (Ori)‐loaded NPC membrane‐based nanovesicles is proposed, which is further grafted with growth and differentiation factor 5 (GDF5) on the OHA chain via Schiff base ligation. The precursors can rapidly form mechanically resilience hydrogels after injection into nucleus pulposus (NP) through the formation of various dynamic bonds. Meanwhile, the acidic pH in the degenerated NP can trigger the responsive release of GDF5, which may cooperate with Ori to alleviate inflammation in the microenvironment for restoring the metabolic homeostasis of ECM. In addition, the Schiff base moieties in HPGO hydrogel can scavenge free ferrous ions in the microenvironment to strengthen the dynamic bonds for self‐regulated reinforcement, thus providing mechanical support for the degenerated intervertebral discs (IVDs). Furthermore, HPGO hydrogel can enhance ferroptosis resistance of NPCs by activating the nuclear factor erythoid 2‐related factor 2 signaling pathway. Overall, HPGO hydrogel can mechanically support the damaged IVDs as well as reversing their degenerative status through cooperative ferroptosis inhibition, which provides an approach for the clinical treatment of IDD. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the College Of Basic Education is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigates the viscoelastic deformation mechanisms of bone as a response to Vickers hardness indentation. We utilized advanced high-resolution scanning electron microscopy (SEM) to investigate a distinct deformation pattern that originates from the indentation site within the bone matrix. The focus of our research was to analyze a unique deformation mechanism observed in bone tissue, which has been colloquially termed as "screw-like" due to its resemblance to a screw thread when viewed under an optical microscope. The primary goals of this research are to investigate the distinctive characteristics of the "screw-like" deformation pattern and to determine how the microstructure of bone influences the initiation and control of this mechanism. These patterns, emerging during the dwell period of indentation, underscore the viscoelastic nature of bone, indicating its propensity for energy dissipation and microstructural reconfiguration under load. This study uncovered a direct correlation between the length of the "screw-like" deformation and the duration of the indentation dwell time, providing quantifiable evidence of the bone's viscoelastic behavior. This finding is pivotal in understanding the mechanical properties of bone, including its fracture toughness, as it relates to the complex interplay of factors such as energy dissipation, microstructural reinforcement, and stress distribution. Furthermore, this study discusses the implications of viscoelastic properties on the bone's ability to resist mechanical challenges, underscoring the significance of viscoelasticity in bone research. [ABSTRACT FROM AUTHOR]

Due to its ability to improve mechanical properties when incorporated into cement, graphene oxide (GO) has received extensive attention from scholars. Graphene oxide is also a filler that improves the self-sensing properties of cement composites (CCs). However, existing studies have not focused sufficient attention on the electric conductivity of cement composites filled with graphene oxide (GO/CCs) and their mechanisms, especially polarization. This study examines the effects of water content and temperature on the electrical conductivity of GO/CCs. GO/CC polarization phenomena are analyzed to reveal the conductive mechanism. The results show that water has a significant influence on the electrical conductivity of GO/CCs. With increasing water loss, the electrical resistivity of GO/CCs increases by four orders of magnitude. For the same water content, a 0.1% GO concentration significantly decreases the resistivity of GO/CCs. Temperature can significantly enhance the current intensity of GO/CCs; furthermore, there is a quadratic relationship between current intensity and temperature. The conductive mechanism of GO/CCs is attributed to the interaction between ionic conductivity and electronic conductivity. [ABSTRACT FROM AUTHOR]

In this study, we investigated the roles of ROCK1 in regulating structural and functional features of caveolae located at the cell membrane of cardiomyocytes, adipocytes, and mouse embryonic fibroblasts (MEFs) as well as related physiopathological effects. Caveolae are small bulb‐shaped cell membrane invaginations, and their roles have been associated with disease conditions. One of the unique features of caveolae is that they are physically linked to the actin cytoskeleton that is well known to be regulated by RhoA/ROCKs pathway. In cardiomyocytes, we observed that ROCK1 deficiency is coincident with an increased caveolar density, clusters, and caveolar proteins including caveolin‐1 and ‐3. In the mouse cardiomyopathy model with transgenic overexpressing Gαq in myocardium, we demonstrated the reduced caveolar density at cell membrane and reduced caveolar protein contents. Interestingly, coexisting ROCK1 deficiency in cardiomyocytes can rescue these defects and preserve caveolar compartmentalization of β‐adrenergic signaling molecules including β1‐adrenergic receptor and type V/VI adenylyl cyclase. In cardiomyocytes and adipocytes, we detected that ROCK1 deficiency increased insulin signaling with increased insulin receptor activation in caveolae. In MEFs, we identified that ROCK1 deficiency increased caveolar and total levels of caveolin‐1 and cell membrane repair ability after mechanical or chemical disruptions. Together, these results demonstrate that ROCK1 can regulate caveolae plasticity and multiple functions including compartmentalization of signaling molecules and cell membrane repair following membrane disruption by mechanical force and oxidative damage. These findings provide possible molecular insights into the beneficial effects of ROCK1 deletion/inhibition in cardiomyocytes, adipocytes, and MEFs under certain diseased conditions. [ABSTRACT FROM AUTHOR]

The management of mechanical ventilation (MV) remains a challenge in intensive care units (ICUs). The digitalization of healthcare and the implementation of artificial intelligence (AI) and machine learning (ML) has significantly influenced medical decision-making capabilities, potentially enhancing patient outcomes. Acute respiratory distress syndrome, an overwhelming inflammatory lung disease, is common in ICUs. Most patients require MV. Prolonged MV is associated with an increased length of stay, morbidity, and mortality. Shortening the MV duration has both clinical and economic benefits and emphasizes the need for better MV weaning management. AI and ML models can assist the physician in weaning patients from MV by providing predictive tools based on big data. Many ML models have been developed in recent years, dealing with this unmet need. Such models provide an important prediction regarding the success of the individual patient's MV weaning. Some AI models have shown a notable impact on clinical outcomes. However, there are challenges in integrating AI models into clinical practice due to the unfamiliar nature of AI for many physicians and the complexity of some AI models. Our review explores the evolution of weaning methods up to and including AI and ML as weaning aids. [ABSTRACT FROM AUTHOR]

Exploring the fundamental mechanisms of locomotion extends beyond mere simulation and modeling. It necessitates the utilization of physical test benches to validate hypotheses regarding real-world applications of locomotion. This study introduces cost-effective modular robotic platforms designed specifically for investigating the intricacies of locomotion and control strategies. Expanding upon our prior research in electric–pneumatic actuation (EPA), we present the mechanical and electrical designs of the latest developments in the EPA robot series. These include EPA Jumper, a human-sized segmented monoped robot, and its extension EPA Walker, a human-sized bipedal robot. Both replicate the human weight and inertia distributions, featuring co-actuation through electrical motors and pneumatic artificial muscles. These low-cost modular platforms, with considerations for degrees of freedom and redundant actuation, (1) provide opportunities to study different locomotor subfunctions—stance, swing, and balance; (2) help investigate the role of actuation schemes in tasks such as hopping and walking; and (3) allow testing hypotheses regarding biological locomotors in real-world physical test benches. [ABSTRACT FROM AUTHOR]

Responsive synthetic receptors for adaptive recognition of different ionic guests in a competitive environment are valuable molecular tools for not only ion sensing and transport, but also the development of ion-responsive smart materials and related technologies. By virtue of the mechanical chelation and ability to undergo large-amplitude co-conformational changes, described herein is the discovery of a chameleon-like [2]catenane that selectively binds copper(I) or sulfate ions and its associated co-conformational mechanostereochemical switching. This work highlights not only the advantages and versatility of catenane as a molecular skeleton in receptor design, but also its potential in constructing complex responsive systems with multiple inputs and outputs. By virtue of the rotational motions of interlocked macrocycles, the authors describe a chameleon-like catenane host that can adjust its co-conformation for selective binding to copper(I) or sulfate ion. While the cationic copper(I) complex is achiral, the interlocked rings in the catenane host rotate and re-orient into a chiral co-conformation upon forming the anionic sulfate complex. [ABSTRACT FROM AUTHOR]

Calcium phosphate materials synthesized from apatite with atomic Ca/P ratios ranging from 1.50 to 1.67 (Ca10-x(HPO4)x(PO4)6-x(OH)2-x (0 ≤ x ≤ 1)) have very interesting applications in bone regeneration and in the environment field for the removal of toxic species. The physicochemical characteristics of synthetic calcium apatite change when the Ca/P ratio varies. In this study, two batches of apatite powder were prepared by precipitation in an aqueous medium at 25 °C with Ca/P molar ratios that were close to those of tricalcium phosphate (1.48, 1.50, and 1.52) and close to those of hydroxyapatite (1.65, 1.67, and 1.72). For dried and ceramized powders, the chemical composition, morphology, surface area, compacity, durability, and crystalline phases of prepared powders were studied. The result shows that the dried powders composed of nanocrystals are poorly crystallized. The sample with the lowest Ca/P atomic ratio (1.48) shows the lowest specific surface area (75 ± 5 m2/g) with good compaction ability and acceptable mechanical properties. While stoichiometric HAP (Ca/P = 1.67) has a large specific area (110 ± 5 m2/g), however, it has poor compaction properties. Calcined apatite (Ca/P = 1.65) at 900 °C composed of HAP with traces of tricalcium phosphate (Ca3(PO4)2: βTCP) shows a higher compressive strength (78 ± 10 MPa). βTCP ceramic with Ca/P = 1.48 has the lowest optical gap (OG = 4.6 ± 0.4 eV). The result of this study shows how little changes in the Ca/P ratio had an impact on the granular properties of dried and calcined calcium phosphate materials. Apatite produced with slightly sub-stoichiometric calcium has the potential for promising future uses in the biological, catalytic, and environmental domains. [ABSTRACT FROM AUTHOR]

Magnetorheological elastomers (MREs) are a category of smart materials composed of a magnetic powder dispersed in an elastomeric matrix. They are characterized by the ability to change their mechanical properties when an external magnetic field is applied, called magnetorheological (MR) effect. When a conductive filler is added to a magnetorheological elastomer, the resulting hybrid filler composite showcases both MR and piezoresistive effects. For such a reason, these composites are referred to as self‐sensing magnetorheological elastomers. In this case, the synthesized self‐sensing magnetorheological elastomers are based on styrene‐based thermoplastic elastomers (TPS), carbonyl iron particles (CIP), and carbon black (CB). The hybrid filler concept using various coated CIP and constant CB content showed that above 25 vol.% CIP the resistivity increased rapidly. This work proposes the first case of a 3D printable self‐sensing magnetorheological elastomer and cyclic mechanical compression and tensile mode analysis at high deformation (up to 20% and 10%, respectively). The results showcase a magnetoresistive change of up to 68% and a piezoresistive change of up to 42% and 98% in compression and tension, respectively. In addition, the magnetostriction of the self‐sensing samples has been characterized to be 3.6% and 5.6% in the case of CIP 15 and 30 vol.%, respectively. [ABSTRACT FROM AUTHOR]