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Carbonation-Cured Cementitious Materials Incorporating Waste Rubber/Slag with Balanced Mechanical Strength and Microwave Absorption Performance.

Electromagnetic wave absorption ability and mechanical strength are critical performance metrics for cement-based microwave-absorbing materi … s Ca(OH)2 into CaCO3, resulting in notable gains in mechanical performance-compressive strength and flexural strength are elevated by 38% and 23%, respectively. This work not only achieves a balanced optimization of electromagnetic wave absorption and mechanical robustness in cement-based materials but also offers a sustainable pathway for the high-value utilizatio …

Novel Aryl Phosphate for Improving Fire Safety and Mechanical Properties of Epoxy Resins.

Epoxy resins (EPs) are highly flammable, and traditional flame retardant modifications often lead to a significant reduction in their mechan … polyaromatic structure of DMP had good compatibility with the EP matrix, and the tensile strength, flexural strength and impact strength of EP/9 wt% DMP were enhanced by 116.38%, 17.84% and 59.11% in comparison with that of pure EP. This study is valuable for expanding the application of flame-retardant EP/DMP thermosets in emerging fields.

Physical and Mechanical Properties of Particleboard Produced with Addition of Walnut (Juglans regia L.) Wood Residues.

The depletion of natural resources and increased demand for wood and wood-based materials have directed researchers and the industry towards alternative raw materials for composite manufacturing, such as agricultural waste and wood residues as substitutes of traditional wood. The potential of reusing walnut (Juglans regia L.) wood residues as an alternative raw material in particleboard manufacturing is investigated in this work. Three-layer particleboard was manufactured in the laboratory with a thickness of 16 mm, target density of 650 kg∙m-3 and three different levels (0%, 25% and 50%) of w

Experimental and material characterization of composites, including waste iron and marble powder.

Due to its fine particle size, waste marble slurry originating in cutting and processing units mixes into the air after drying, causing envi … or natural aggregates were mainly responsible for the increase in mechanical performance. A maximum flexural strength of 5.9 MPa and a compressive strength of 26.7 MPa were observed in 28-day composites containing 0% marble-20% iron wastes. Furthermore, capillary water absorption tended to decrease with the substitution of 10% marble powder.

Short fiber reinforced composite on fracture strength of immature permanent anterior teeth with simulated regenerative endodontic procedures: an in vitro study.

The aim of the present study was to evaluate the effect of short fiber reinforced composite on the fracture strength of anterior immature teeth treated with regenerative endodontic procedures. A total of 120 permanent maxillary central incisors were selected, and root lengths were standardized. Except for the positive control group (n = 20), the root canals were instrumented to simulate immature teeth with incomplete root development, and the regenerative endodontic procedure was performed. Twenty instrumented teeth acted as negative controls (n = 20), and the remaining 80 teeth were randomly

Fracture strength of different veneers on polyetheretherketone (PEEK) frameworks in implant-supported single crowns.

PURPOSE: To evaluate the fracture strength of polyetheretherketone (PEEK) single crowns veneered with different materials produced by computer-aided design (CAD)-computer-aided manufacture (CAM) after aging. METHODS: 60 stainless-steel master dies were prepared with a 1 mm-wide deep chamfer. Sixty PEEK frameworks were produced with a CAD-CAM system for the right maxillary first molar tooth on the dies. PEEK frameworks were divided into six groups (n= 10) according to veneering materials (five CAD-CAM materials and a resin composite). Group ZR: monolithic zirconia (Upcera ST-Color); Group EC:

Fracture strength of endodontically treated premolars restored with different post systems and metal-ceramic or monolithic zirconia crowns.

The purpose of this study was to investigate the fracture strength of endodontically treated human maxillary premolars (ETP) restored with posts and metal ceramic (MC) or monolithic zirconia (MZ) crowns. Sixty ETP were randomly divided into 3 groups. Teeth in control group (C) received a resin filling. ETP in the MC group were restored with prefabricated metal posts, composite cores and MC crowns while in the MZ group with glass-fiber posts, composite cores and MZ crowns. Half of the specimens were loaded at a 135° angle and half under axial loading until fracture. The fracture modes were divi

Fracture strength of various titanium-based, CAD-CAM and PFM implant crowns.

OBJECTIVE: CAD-CAM has dramatically advanced dental restorative procedures to include implant-supported crowns. The purpose of this study was to compare the fracture resistance following mechanical loading and thermocycling of various screw-retained and cement-retained ceramic and polymethylmethacrylate material combinations using the TiBase abutment compared to PFM implant-supported crowns. OVERVIEW: Twelve implant restorations were fabricated for each of eight groups. Three groups were screw-retained and five groups were cement-retained implant restorations. The ceramic and polymethylmethac

An Investigation on the Correlation between the Mechanical Properties of Human Skull Bone, Its Geometry, Microarchitectural Properties, and Water Content.

With increasingly detailed imaging and mechanical analysis, modalities need arises to update methodology and assessment criteria for skull bone analysis to understand how bone microarchitecture and the presence of attached tissues may affect the response to mechanical load. The main aim was to analyze the effect of macroscopic and microstructural features, as well as periosteal attachment, on the mechanical properties of human skull bone. Fifty-six skull specimens from ethanol-phenoxyethanol-embalmed cadavers were prepared from two human cadavers. Assuming symmetry of the skull, all samples fr

Performance Evolution and Microstructure Optimization of Recycled Fine Aggregate Rapid-Hardening Sulfoaluminate Cement Mortar by Nano-SiO2 Surface Modification.

In this study, rapid-hardening sulfoaluminate cement (SAC) was used as cementitious material, and recycled fine aggregates (RFAs) were surfa … ogeneous nucleation and the pozzolanic reaction. At a cement-sand ratio of 1:1, the compressive and flexural strengths gradually increase as the NS concentration rises from 0% to 2%. Compared with the control group, the 28 d compressive and flexural strength are enhanced by 19.5% and 16.6%, respectively, the drying shrinkage decreases by 8.0%, and carbonation resis …

Улучшить долгосрочные механические свойства термопластических короткокалорийных соединений с использованием альтернативных матриц.

Древесные пластиковые композитные материалы (ВКН) обеспечивают средства для уменьшения углеродного следа за счет использования натуральных волокон для повышения механических свойств. Однако имеется ограниченная информация о механических свойствах этих материалов во враждебных условиях. В этом исследовании была проведена оценка составов полипропилена (PP), полистирола (PS) и полилактической кислоты (PLA), обработанных путем экструдирования и инъекции. Были проведены испытания на прочность и модулю прочности на растяжение и флексур, температуру смещения тепла (HDT) и на анализ ползучести при раз

Совпадение в аннотации оригинала
Wood plastic composites (WPCs) offer a means to reduce the carbon footprint by incorporating natural fibers to enhance the mechanical proper … actic acid (PLA) processed via extrusion and injection molding. Tests were conducted on tensile and flexural strength and modulus, heat deflection temperature (HDT), and creep analysis under varying relative humidity conditions (10% and 90%) and water immersion, followed by freeze-thaw cycles. The addition of fibers generally improved the mechanical properties but …

Mechanical, Antibacterial, and Antibiofilm Properties of Iron Carbide-Doped 3D-Printed Bioactive Glass Scaffolds.

The management of large-scale bone defects, particularly in oncological contexts, necessitates scaffolds that provide both structural resili … . Compressive and compressive-shear tests were conducted to evaluate the strength of MBG scaffolds. Flexural strength and fracture toughness were evaluated through three-point bend tests. The Gyroid structure exclusively exhibited comparatively good mechanical properties, potent antibacterial activity against two antibiotic-resistant bacteria (ARBs) of E. coli and …

Properties investigation on 3D-printed polyetherketoneketone (PEKK) - a proper candidate for bone replacement.

Polyetherketoneketone (PEKK) has emerged as a highly promising material for bone substitutes due to its superior mechanical properties, biocompatibility, and patient-specific design capabilities. This study systematically investigated the mechanical properties of fused filament fabrication (FFF) 3D-printed PEKK in various printing orientations and found that PEKK specimens exhibited three times the tensile strength and flexural strength in the Z-axis compared to polyetheretherketone (PEEK). Surface assessments revealed that PEKK surfaces had greater roughness and wettability than those of PEEK…

Biocomponents Based on Hydroxiapatite: Influence of Sterilization on the Mechanical Resistance.

Objective  This study aimed to evaluate the influence of sterilization on the compressive and flexural mechanical strength of hydroxyapatite … pecimens sterilized by gamma rays when compared with the control group ( p  = 0.0245). However, low flexural strengths were observed in all specimens. Conclusion  The autoclave sterilization group did not result in statistically significant differences in either compression or flexion strength tests. Thus, the autoclave proved to be the best sterilization option fo …

Sustainable epoxy composites from hemp/pineapple/glass fibers for lightweight automobile panels.

The rapid industrial revolution has led to increased use of synthetic materials in various automotive panel applications, resulting in envir … ealed that the pure hemp composite with intermediate glass layers exhibited the highest tensile and flexural strengths, at 58.24 MPa and 98.35 MPa, respectively. Viscoelastic analysis indicated that the pure pineapple fiber composite demonstrated the highest storage modulus of 2875.51 MPa, consistent with the observed flexural modulus trend. However, this configura …

The effects of different neck training methods on the neck function of aviation cadets.

To compare the effects of different neck eccentric training devices on the neck strength and endurance of aviation cadets, and to explore their roles in the prevention of neck injuries, providing a basis for introducing specialized neck training in adolescent aviation schools. Two intervention groups used a helmet-style neck training device and elastic bands for neck training, respectively, while the control group underwent regular resistance physical training without additional neck intervention. Tests were conducted on neck flexion, extension, lateral flexion, and rotation in six directions

Strong and Flexible Braiding Pattern of Carbon Nanotubes for Composites: Stiff and Robust Structure Active in Composite Materials.

Carbon nanotubes (CNTs) exhibit high strength, Young's modulus, and flexibility and serve as an ideal reinforcement for composite materials. Owing to their toughness against bending and/or twisting, they are typically used as fabric composites. The conventional multiaxial braiding method lacks tension and resultant strength in the thickness direction. Some braiding patterns are proposed; however, they may have shortcomings in flexibility. Thus, this study proposed three types of braiding pattern for fabrics based on natural products such as spider net and honeycomb, in accordance with thicknes

Disinfection protocols during COVID-19 pandemic and their effects on prosthetic surfaces: a systematic review.

PURPOSE: To describe the possible adverse effects of sodium hypochlorite (NaOCl) solutions, high-concentration alcohol solutions, and povido … on. The remaining articles evaluated color alteration, surface roughness modifications, decrease in flexural strength, and bonding strength of all cleaning agents on acrylic resin. CONCLUSION: NaOCl (1%) solution for 1 minute is recommended to reduce SARS-CoV infectivity and to minimize the risk of cross-contamination through prosthetic materials. The increase in …

Sustainable development of additively manufactured PLA composites reinforced with agro-waste derived bio-filler: Structural and flame-retardant performances.

The increasing reliance on conventional composite materials has raised concerns regarding cost and environmental sustainability, particularl … spectively, with the 95PLA/5PALF composite exhibiting the optimum overall performance. In contrast, flexural strength decreased relative to neat PLA. Flammability testing further demonstrated enhanced flame resistance, attributed to char formation and the resulting barrier effect, which reduced the burning rate. The developed PLA/PALF bio-composites provide a susta …

Comparative evaluation of mechanical characteristics of nanofiller containing resin composites.

PURPOSE: To determine basic mechanical characteristics of six commercially available nanofiller containing resin composites compared to a mi … (VED). The following material characteristics were determined after 24 hours water storage (n = 6): Flexural strength and modulus (FM), yield stress (0.02%), tensile strength and modulus (TM), diametral tensile strength, Knoop hardness (KHN), and fracture toughness (KIC). RESULTS: The microfilled composite DUR consistently showed the lowest values for each propert …