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Hybridization of natural fibers with ceramic materials for reinforcing composites allows the optimization of the properties of these materials. For this reason, the present study aims to investigate physical, mechanical, water absorption, swelling and thermal properties as well as morphological characteristics of a hybrid Paederia foetida fibers–alumina powder (PFs–Al2O3)‐reinforced epoxy composite. Epoxy resin served as the matrix, while PFs and Al2O3 were employed as reinforcement. Five types of composites were fabricated using the hot‐pressing technique. The corresponding ratios of PFs:Al2O3 volume fractions (%) considered here were 0:40 (SFA), 10:30 (SFB), 20:20 (SFC), 30:10 (SFD) and 40:0 (SFE). The results reveal that the density of the hybrid PFs–Al2O3 composites decreased for increasing volume fractions of PFs: from 2.173 g cm−3 of SFA to 1.042 g cm−3 of SFE. The highest values of tensile strength (i.e. 49.085 MPa), tensile elastic modulus (i.e. 1.431 GPa) and impact strength (24 kJ m−2) were obtained for the SFD composite material with 30% volume fraction of PFs and 10% volume fraction of Al2O3: this happened because interface bonds between PFs, Al2O3 and epoxy phases achieved their optimal configuration. Overall, mechanical properties of the hybrid PFs–Al2O3‐reinforced epoxy composites were superior to those of composites reinforced only by PF fibers or only by Al2O3. Water absorption and swellability reached their maximum values at the steady state occurring after tested samples remained immersed in water for 820 h. The SFE composite reinforced only by PFs presented the highest water absorption and swelling (i.e. 6.034% and 5.81%, respectively) while for all other hybrid composites (SFD, SFC and SFB) these two quantities remained below 5%. Density and volume fraction of voids of hybrid PFs–Al2O3‐reinforced composites were consistent with the corresponding properties of the composites reinforced only by Al2O3 or PFs. SFD was also the most thermally stable material. Scanning electron microscopy observations of fractured surfaces indicated that the microstructure of the PFs–Al2O3‐reinforced epoxy composites presents several voids, fiber pullouts and transverse fibers, which together optimize the mechanical response of the composite material. Remarkably, the SFD composite material was highly competitive with the most recently developed hybrid composites employing natural reinforcements. © 2024 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Prosthetic retention relies on the perfect adaptation between the cap and the abutment of a dental implant. The conometric connection ensures retention similar to cemented systems, preventing bacterial infiltration and sustaining a high implant success rate. Furthermore, the material used for the cap plays a crucial role in distributing stress on the implant components and bone. Traditionally, caps use titanium (Ti), but ongoing research investigates polyetheretherketone (PEEK) for its bone‐like qualities and similar elasticity to Ti. In this finite‐element analysis study, stress and strain distributions are compared between crestal and subcrestal implants using Ti and PEEK conometric caps, assessing retention through cap displacement to determine the material best suited for proper retention aligned with implant insertion depth. In the findings, an improvement in stress and strain is indicated on trabecular bone, a reduction in stress on cortical bone, and thus enhanced implant stability due to higher stresses around the implant threads, particularly with PEEK coping and subcrestal placement. Consequently, PEEK emerges as a promising substitute for Ti in conometric caps as it absorbs stress more effectively, distributing it across prosthetics to counter stress shielding and prevent implant failure. [ABSTRACT FROM AUTHOR]

This paper presents a critical review on the measuring methods and parameters affecting nano-tribology in the context of nano-scale wear. Nano-scale wear phenomena play a crucial role in various industries, including micro/nano-systems, electronics, and biotechnology. The review begins by discussing the significance of nano-scale wear and its impact on device performance, lifespan, durability, energy efficiency, cost savings, and environmental sustainability. It then delves into the measuring methods employed to assess nano-scale wear, including scanning probe microscopy (SPM) techniques such as atomic force microscopy (AFM) and friction force microscopy (FFM). The capabilities of AFM and FFM in studying the roughness of surface, adhesion, friction, scratch, abrasion, and nano-scale material transfer are highlighted. Additionally, the review explores the parameters affecting nano-wear, such as lubrication strategies, stress levels, sliding velocity, and atomic-scale reactions. The article concludes by emphasizing the importance of advanced microscopy techniques in understanding tribological mechanisms at different scales, bridging the gap between macro and nano-tribology studies. [ABSTRACT FROM AUTHOR]

Mechanical characterization of soft materials is a complicated inverse problem that includes nonlinear constitutive behavior and large deformations. A further complication is introduced by the structural inhomogeneity of tested specimens (for example, caused by thickness variations). Optical methods are very useful in mechanical characterization of soft matter, as they provide accurate full-field information on displacements, strains and stresses regardless of the magnitude and/or gradients of those quantities. In view of this, the present study describes a novel hybrid framework for mechanical characterization of soft membranes, combining (i) inflation tests and preliminary in-plane equi-biaxial tests, (ii) a one-shot projection moiré optical setup with two symmetric projectors that project cross-gratings onto the inflated membrane, (iii) a mathematical model to extract 3D displacement information from moiré measurements, and (iv) metaheuristic optimization hybridizing harmony search and JAYA algorithms. The use of cross-gratings allows us to determine the surface curvature and precisely reconstruct the shape of the deformed object. Enriching metaheuristic optimization with gradient information and elitist strategies significantly reduces the computational cost of the identification process. The feasibility of the proposed approach wassuccessfully tested on a 100 mm diameter natural rubber membrane that had some degree of anisotropy in mechanical response because of its inhomogeneous thickness distribution. Remarkably, up to 324 hyperelastic constants and thickness parameters can be precisely identified by the proposed framework, reducing computational effort from 15% to 70% with respect to other inverse methods. [ABSTRACT FROM AUTHOR]

Remarkably, the proposed algorithms outperformed other stitching algorithms currently available in the literature in the four selected test cases in [[3]] (i.e., polymer abrasion, mirror polished copper, arm skin replica, and titanium alloy abrasion). Materials characterization is a basic field of science and engineering. For this reason, Abdelhamid et al. [[5]] developed Cu- and/or Zr-modified TiO SB 2 sb nanoparticles, characterizing them with photo-thermal beam deflection spectrometry (BDS), UV-Vis spectro-photometry, X-ray diffraction (XRD), and energy-dispersive X-rays (EDXs) to determine their thermo-optical and transport parameters. [Extracted from the article]