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Advances in nanoparticle (NP) production and demand for control over nanoscale systems have had significant impact on tissue engineering and regenerative medicine (TERM). NPs with low toxicity, contrasting agent properties, tailorable characteristics, targeted/stimuli-response delivery potential, and precise control over behavior (via external stimuli such as magnetic fields) have made it possible their use for improving engineered tissues and overcoming obstacles in TERM. Functional tissue and organ replacements require a high degree of spatial and temporal control over the biological events and also their real-time monitoring. Presentation and local delivery of bioactive (growth factors, chemokines, inhibitors, cytokines, genes etc.) and contrast agents in a controlled manner are important implements to exert control over and monitor the engineered tissues. This need resulted in utilization of NP based systems in tissue engineering scaffolds for delivery of multiple growth factors, for providing contrast for imaging and also for controlling properties of the scaffolds. Depending on the application, materials, as polymers, metals, ceramics and their different composites can be utilized for production of NPs. In this review, we will cover the use of NP systems in TERM and also provide an outlook for future potential use of such systems.

Magnesium matrix composites are essential lightweight metal matrix composites, following aluminum matrix composites, with outstanding application prospects in automotive, aerospace lightweight and biomedical materials because of their high specific strength, low density and specific stiffness, good casting performance and rich resources. However, the inherent low plasticity and poor fatigue resistance of magnesium hamper its further application to a certain extent. Many researchers have tried many strengthening methods to improve the properties of magnesium alloys, while the relationship between wear resistance and plasticity still needs to be further improved. The nanoparticles added exhibit a good strengthening effect, especially the ceramic nanoparticles. Nanoparticle-reinforced magnesium matrix composites not only exhibit a high impact toughness, but also maintain the high strength and wear resistance of ceramic materials, effectively balancing the restriction between the strength and toughness. Therefore, this work aims to provide a review of the state of the art of research on the matrix, reinforcement, design, properties and potential applications of nano-reinforced phase-reinforced magnesium matrix composites (especially ceramic nanoparticle-reinforced ones). The conventional and potential matrices for the fabrication of magnesium matrix composites are introduced. The classification and influence of ceramic reinforcements are assessed, and the factors influencing interface bonding strength between reinforcements and matrix, regulation and design, performance and application are analyzed. Finally, the scope of future research in this field is discussed.

Lately, children's daily consumption of some products, such as cereals and candies, has been rising, which provides a compelling rationale for determining any metallic substances that may be present. Monitoring the concentration of certain metals, like nickel, in these products is necessary due to medical issues in humans when consumed regularly. So, in this work, a novel and highly selective carbon paste as a Ni(II) ion-selective sensor was prepared and investigated using ceramic magnesium aluminum spinel nanoparticles as the ionophore and tritolyl phosphate (TOCP) as a plasticizer. A modified co-precipitation method was used to synthesize the spinel nanoparticles. X-ray diffraction, scanning electron microscope with EDAX, transmission electron microscope, and BET surface area were used to determine the phase composition, microstructure, pores size, particle size, and surface area of the synthesized nanoparticles. The spinel nanoparticle was found to have a nano crystallite size with a cubic crystal system, a particle size ranging from 17.2 to 51.52 nm, mesoporous nature (average pore size = 8.72 nm), and a large surface area (61.75 m 2 /g). The composition ratio of graphite carbon as a base: TOCP as binder: spinal as ionophore was 67.3:30.0:2.7 (wt%) based on potentiometric detections over concentrations from 5.0 × 10 −8 to 1.0 × 10 −2  mol L −1 with LOD of 5.0 × 10 −8  mol L −1 . A measurement of 29.22 ± 0.12 mV decade −1 over pH 2.0–7.0 was made for the Nernstian slope. This sensor demonstrated good repeatability over nine weeks and a rapid response of 8 s. A good selectivity was shown for Ni(II) ions across many interferents, tri-, di-, and monovalent cations. The Ni(II) content in spiked real samples, including cocaine, sweets, coca, chocolate, carbonated drinks, cereals, and packages, were measured. The results obtained indicated no significant difference between the proposed potentiometric method and the officially reported ICP method according to the F- and t-test data. In addition to utilizing ANOVA statistical analysis, validation procedures have been implemented, and the results exceed the ICP-MS methodology.

This work aimed to advance the knowledge in the field of eco-friendly dielectrics with applicative relevance for future energy-related technologies. New multicomponent composites were prepared by using a cellulose ether/citric acid mixture as the matrix, which was gradually filled with strontium titanate nanoparticles (5–20 wt%). In this case, citric acid can act as a crosslinking agent for the polymer but also can react differently with the other counterparts from the composite as a function of the solvent used (H2O and H2O2). This led to considerable differences in the morphological, thermal, optical, and electrical characteristics due to distinct solvent-driven interactions, as revealed by the infrared spectroscopy investigation. Hence, in contrast to H2O, the oxidizing activity of H2O2 led to changes in the surface morphology, a greater transparency, a greater yellowness, an enhanced refractive index, and higher permittivity. These data provide new pathways to advance the optical and dielectric behavior of eco-compatible materials for energy devices by the careful selection of the composite’s components and the modulation of the molecular interactions via solvent features.

Magnesium silicate nanoparticles were found to be an effective adsorbent for aniline blue dye from wastewater. Using the sol-gel technique, magnesium silicate nanoparticles were synthesized and characterized using X-ray diffraction (XRD), transmission electron microscope (TEM), Brunauer-Emmett-Teller (BET) surface area, and fourier transform infrared spectroscopy (FTIR). Aniline blue removal was done at room temperature, pH 4, and a dosage of 3 g/L was about 99% in the first 30 min. Magnesium silicate can also be used for four cycles to adsorb Aniline blue dye without the need for disposal, which supports the principle of recycling. Response surface methodology was used for statistical analysis to investigate the impact of the factors. By studying the isotherms, kinetics, and thermodynamics, it became clear that the adsorption process involves a physical interaction that adheres to the Freundlich isotherm, follows pseudo-first-order kinetics, with the boundary layer (film) diffusion identified as the rate-determining step. The process is endothermic and spontaneous. Magnesium silicate nanoparticles were successfully used to remove dye contaminants from various actual water samples. The material’s reliability and potential for real-world environmental applications were demonstrated by the high efficiency and consistent adsorption results across multiple sample types.

The heterogeneous photocatalysis process has been known to provide significant levels of degradation and mineralization of emerging contaminants including antibiotics. For that, nanoparticle CuCr 2 O 4 (CCO) ceramics were successfully prepared via sol-gel (SG) and co-precipitation (CP) methods to obtain spinel with desired structural features and properties and also to improve the photocatalytic performances. The CCO crystallite phase was produced at 750 °C all ceramics, disregarding the synthesis route. CCO physical and chemical properties were checked by X-ray diffraction (XRD) with Rietveld refinement, Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscope (SEM), transmission electron microscope (TEM), and diffuse reflectance solid (DRS). The XRD patterns demonstrated that the synthesized catalysts displayed a small crystallite size between 17.45 and 26.24 nm for SG and 20.97 and 36.86 nm for the CCO CP samples. The observation by SEM and TEM of the nanopowders showed a typical morphology with comparable particle sizes for both synthesized routes (20–30 nm). SG agglomeration rates were higher, and particles stick together more efficiently considering the CP method, while the CCO CP method led to a more significant porosity. Their photocatalytic and adsorption performances were examined for cefaclor (CFC) removal chosen as a target pharmaceutical contaminant in water. The results obtained by the methods differed since nanoparticles prepared by SG led to high photocatalytic activity. In contrast, a high CFC adsorption was observed for those prepared via the CP method, and that agreed with the findings of the characterization analysis. The kinetics of the adsorption process was found to follow the pseudo-second-order rate law. In contrast, the data of the photodegradation process were further found to comply with the Lagergren kinetic law. Nevertheless, the global reaction rate is probably controlled by the intra-particular diffusion of CFC, regardless of the elimination process.

Ceramic/polymer composites have been considered as third-generation orthopedic biomaterials due to their ability to closely match properties (such as surface, chemistry, biological, and mechanical) of natural bone. It has already been shown that the addition of nanophase compared with conventional (or micron-scale) ceramics to polymers enhances bone cell functions. However, in order to fully take advantage of the promising nanometer size effects that nanoceramics can provide when added to polymers, it is critical to uniformly disperse them in a polymer matrix. This is critical since ceramic nanoparticles inherently have a strong tendency to form larger agglomerates in a polymer matrix which may compromise their properties. Therefore, in this study, model ceramic nanoparticles, specifically titania and hydroxyapatite (HA), were dispersed in a model polymer (PLGA, poly-lactic-co-glycolic acid) using high-power ultrasonic energy. The mechanical properties of the resulting PLGA composites with well-dispersed ceramic (either titania or HA) nanoparticles were investigated and compared with composites with agglomerated ceramic nanoparticles. Results demonstrated that well-dispersed ceramic nanoparticles (titania or HA) in PLGA improved mechanical properties compared with agglomerated ceramic nanoparticles even though the weight percentage of the ceramics was the same. Specifically, well-dispersed nanoceramics in PLGA enhanced the tensile modulus, tensile strength at yield, ultimate tensile strength, and compressive modulus compared with the more agglomerated nanoceramics in PLGA. In summary, supplemented by previous studies that demonstrated greater osteoblast (bone-forming cell) functions on well-dispersed nanophase ceramics in polymers, the present study demonstrated that the combination of PLGA with well-dispersed nanoceramics enhanced mechanical properties necessary for load-bearing orthopedic/dental applications.

To date, additions of different oxide nanoparticles is one of the most widespread procedures to improve the mechanical properties of metals and metal alloys. This research deals with the effect of minor ceramic nanoparticle additions (SiO 2 , TiO 2 and ZrO 2 ) on the microstructure and mechanical properties of Cu/solder/Cu joints. The reinforced Sn3.0Ag0.5Cu (SAC305) solder alloy with 0.5 wt.% and 1.0 wt.% of ceramic nanoparticles was prepared through mechanically stirring. The microstructure of as-solidified Cu/solder/Cu joints was studied using scanning electron microscopy. The additions of ceramic nanoparticles suppressed the growth of the intermetallic compound layer Cu 6 Sn 5 at the interface solder/Cu and improved the microstructure of the joints. Furthermore, measurements of mechanical properties showed improved shear strength of Cu/composite solder/Cu joints compared to joints with unreinforced solder. This fact related to all investigated ceramic nanoinclusions and should be attributed to the adsorption of nanoparticles on the grain surface during solidification. However, this effect is less pronounced on increasing the nanoinclusion content from 0.5 wt.% to 1.0 wt.% due to agglomeration of nanoparticles. Moreover, a comparison analysis showed that the most beneficial influence was obtained by minor additions of SiO 2 nanoparticles into the SAC305 solder alloy.

Polymers with particle inclusions have wide applications, and the mechanical properties of polymer composites affect their reliability in service. The strength of these composites is dependent on factors such as particle fraction, size, distribution, and interface interaction between the two phases, in addition to the properties of the polymers and particles. The size effect of particles and interface damage play an important role and thus draw considerable attention. In this paper, the size- and interface-dependent strength of polypropylene (PP) with nano/micro silica (SiO 2 ) particles of different fractions is studied through a combination of tensile experiments on a series of samples and corresponding three-dimensional (3D) finite element modeling. The results indicate that PP with 2% SiO 2 nanoparticles of 50 nm exhibits relatively higher tensile strength, shedding light on the microstructure mechanism where smaller particle sizes lead to better interface bonding. Furthermore, the particle size and interface coupling effect is analyzed based on the size-dependent elastic modulus model and the interface-cohesive model. The simulation demonstrates the local interface damage evolution around a particle of the composites in tension. These findings are beneficial for designing polymer composites with nanoparticle inclusions.

In current study, microstructural, mechanical and corrosion behaviour were investigated with incorporation of dual reinforced AZ91D surface composites. This research was carried out for enhancement of the bio-degradability in biological environment. The surface composites were successfully fabricated by friction stir processing method with a rotation speed of 800 rpm, travel speed of 80 mm/min and 2.5° tilt angle at multi-passes. The surface properties were characterized via optical, SEM, EDS, XRD and EBSD techniques. The microstructure showed that the reinforcements were equally distributed into the surface matrix after 3-passes for sets of composites. After 3-passes FSP average grain diameter of the composite C (1.61 μm) was smaller than that of composite A (1.86 μm) and composite B (1.63 μm), because of the strong shear deformation and generated friction heat, which occurred via dynamic recrystallization between grains in the processed zones. The microhardness of Composite C (162 Hv) has a higher than the composite A (125.2 Hv) and composite B (146.2 Hv). The ultimate tensile strength of composite A (152.7 MPa) was greater than that of composite B (133 MPa) and composite C (111.3 MPa). Furthermore, the corrosion resistance at 7, 15 and 30 days of immersion of composite C was higher than that of composite A and composite B, because of the domino effects and better bio-mineralization with the addition of Y2O3 and ZrO2 particles. The typically worn surface revealed reduced deep pits, pits and cracks due to better ionization of the hydrogen generated during immersion. Finally, this research was carried out for treatment of bone defects and fractures as well as improving corrosion resistance of the mg-containing biocompatible implants.