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This study introduces a computational simulation which leads to obtaining the critical buckling temperatures of a sandwich microplate which is modeled based on the modified strain gradient theory. This theory includes three material length scale parameters. The core of the microstructure is made from cellular materials which is treated with piezoelectric carbon nanotubes-reinforced composite patches. An advanced trigonometric hyperbolic shear deformation theory, eliminating the need for shear correction factors, is employed to analyze the microstructure. Thickness-dependent variations in structural characteristics are observed based on predefined functions. The equilibrium equations are derived using the virtual displacement principle. Fourier series functions provide an analytical way of solving these equations. The findings are verified by comparison with earlier research that was published and used fewer complex combinations. The study looks at how several important factors affect the structure’s reaction to thermal buckling.

This research is concerned with the thermal bending and stability of temperature-dependent nanocomposite curved pipes strengthened with carbon nanotubes (CNTs) subjected to uniform temperature rise. Thermo-mechanical characteristics of the polymer composite pipe are assumed to vary entirely in the thickness by a non-uniform function of the radius. Five different patterns are selected to model the propagation profile of CNTs amongst the pipe thickness. Based on the shear deformation and von-Karman kinematic hypothesis, nonlinear balance equations of the polymer curved pipe are determined via varying the total potential energy of the system. Governing equations as a set of coupled nonlinear differential equations are analytically solved using a perturbation-based technique. Closed-form solutions are derived to estimate large-amplitude deflection of nanocomposite curved pipes with pinned and clamped boundaries under uniform thermal loading. The obtained results show the influences of important parameters such as material/geometrical characteristics and foundation stiffness on the thermally induced nonlinear response of polymer nanocomposite curved pipes.

Cerium oxide (CeO${}_2)$ and yttrium oxide (Y₂O${}_3)$ nanoparticles possess interesting surface properties and interfacial interactions that make them attractive candidates for various applications. This study presents a comprehensive investigation into the synthesis and toxicity assessment of yttrium-doped cerium oxide (Ce-Y) nanocomposite using a combination of analytical techniques and biological assays. The nanocomposite was characterized using UV–Vis spectroscopy, X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), electron microscopy imaging, dynamic light scattering (DLS), and zeta potential measurements to elucidate their structural, optical and physicochemical properties. The synthesized nanocomposite exhibited distinctive absorption spectra and precise alignment of diffraction peaks, confirming the successful incorporation of yttrium ions into the cerium oxide lattice. Electron microscopy images revealed well-dispersed yttrium particles within the ceria matrix, indicating uniform distribution and morphology. DLS and zeta potential analysis provided insights into the size distribution and stability of the nanocomposite. Furthermore, in vivo toxicity assessment using Drosophila melanogaster model revealed no significant toxicity of Ce:Y nanocomposite, as evidenced by survival assay and behavioral assays. Superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels were also evaluated, demonstrating no discernible nanoparticle-induced toxicity. Overall, this study highlights the potential applications of Ce:Y nanocomposite and underscores the importance of comprehensive toxicity evaluation in nanomaterial development.

Relatively low strength and fracture toughness of ceramics have restricted their applications. Various solutions have been studied to overcome the abovementioned drawbacks. One of the most sophisticated and promising solution is production of multilayer ceramic composites. High hardness, heat and wear resistance, low electrical and thermal conductivity, and resistance to chemical attacks are the most important characteristics of Al₂O₃. Therefore, it is a common candidate for various industrial applications. Multilayer alumina-zirconia composites were made using two methods of isostatic and hydraulic compaction of dry ceramic powders. The green articles were conventionally sintered at 1420, 1550 and 1650°C for 3h. The microstructure and density of composites were investigated. The results show that the pressing method and sintering temperature have a relatively moderate effect on the microstructure and density of the sintered samples.

Nanocrystalline zirconium nitride/oxide "zirconium oxynitride" nanocomposite film is deposited on zirconium substrate by dense plasma focus device at room temperature. X-ray diffraction of irradiated samples reveals that different phases (ZrN, Zr₃ N₄ and ZrO₂) of zirconium nitride and zirconium oxide are evolved. The crystallinity of these phases depends on axial positions as well as ion energy flux. Scanning electron microscopy shows that the deposited film is more compact at lower axial position, which is due to higher ion energy flux. Energy dispersive X-rays spectroscopy shows that the presence of nitrogen concentration decreases by increasing the axial position. Maximum microhardness value for the deposited layer is found to be 7200 ± 12 MPa at 10 gram imposed load.

Polyethylene (PE) film was coated with nanosilica-polyamide layer using rod Mayer process. The nanosilica-polyamide system was prepared by dispersing nanosilica (nano-SiO₂) powder into solvent borne polyamide binder under vigorous stirring. Various compositions of nanosilica-polyamide slurry were prepared. The thickness of the layer was about four µm and eight µm for single and double layer coating respectively. A battery of characterization procedures were used to study the properties of the nanocomposite coating. The uniformity of silica dispersion was probed using elemental mapping procedure and scanning electron microscopy (SEM). With the introduction of nanosilica to polyamide binder, the visible light transmittance and ultra-violet (UV) radiation of nanosilica-polyamide system reduced with increasing nanosilica content and coating layer thickness. Infrared (IR) effectiveness (between 7 µm to 13 µm wavelengths) measurements by FTIR also showed that nanosilica-polyamide system coating on PE film surface greatly improved the thermic effect of PE film. The nanocomposite coating containing 14 wt% nanosilica and with eight µm coating thickness has improved the IR effectiveness of PE to 76%. Thermic effect of the nanocomposite increased with increasing nanosilica content and coating thickness.

Multiwalled carbon nanotubes (MWCNTs) grafted with poly(L-lactide-e-caprolactone) (PCLA) were synthesized by in situ ring opening polymerization and used as a reinforcement for neat PCLA. The analyzed data revealed that the applied tensile load on the composite was transferred to the functionalized MWCNTs, leading to a strain failure of the MWCNTs rather than an adhesive failure between the MWCNTs and the matrix. In comparison between the functionalized and pristine MWCNTs, as reinforcement materials for PCLA random copolymers (80% L-lactide (LA), 20% e-caprolactone (CL)) (PCLAR80), the functionalized MWCNTs are more effective reinforcement materials than pristine MWCNTs. In comparison with the neat PCLAR80, the increasing in tensile strength (28.03%) and elongation at failure (49.6%) when functionalized MWCNT loading reaches 1.0 wt%, indicate that an effective reinforcement of the MWCNT-OH-g-PCLA.

The fracture process and the structure changes of the multi-walled carbon nanotubes (MCNT) during the mechanical ball milling process were investigated and the samples of ball milled powder were observed by SEM. The results indicate that the MCNT turned into nano-whiskers or nano-particles during the ball milling process. The pre-milled MCNT could be distributed in Cu powders homogeneously. The bulk MCNT/Cu nanocomposite were fabricated by hot pressing the mixed MCNT/Cu powders at a temperature of 1073 K under a pressure of 20 MPa and the microstructure of the composites were investigated. It has been found that the multi-walled carbon nanotubes distributed in copper evenly.

A cobalt ferrite/nickel-zinc ferrite core/shell nanocomposite was synthesized by a polymerized complex method using iron citrate, cobalt nitrate, nickel nitrate, zinc nitrate, citric acid, ethylene glycol, benzoic acid and sodium citrate as starting materials. The XRD, TEM and VSM techniques were employed to evaluate the phase composition, morphology and magnetic properties of the samples. The XRD results indicated the coexistence of characteristic reflections of CoFe₂O₄ and Ni_0.5Zn_0.5Fe₂ O₄ spinel ferrites in the composite sample. The core/shell structure of the composite sample has been confirmed by TEM images. The size of obtained spherical core/shell nanoparticles was 20–40 nm in core diameter and about 10 nm in shell thickness. The VSM results showed that both the coercivity and the saturation magnetization of the resulting core/shell nanocomposite were decreased compared to those of the CoFe₂O₄ core, due to the interaction at the interface of CoFe₂O₄ and Ni_0.5Zn_0.5Fe₂O₄.

Bilayers of Sm–Co/Fe have been fabricated on 70 nm Cr buffered Si(100) substrate at an elevated temperature of 650^°C by the help of DC and RF magnetron sputtering. Very thin layers (0–0.7 nm) of Ti were introduced at the interface of the Sm–Co and Fe phases. The samples were analyzed by X-ray diffraction (XRD) and alternating gradient magnetometer (AGM). All the samples showed strong exchange coupling and single phase behavior. The rise and fall in magnetization and energy product were observed with increasing Ti interlayer thickness. Energy product (BH)_max value was found increased by 44% for 0.2 nm Ti interlayer as compared to the sample without Ti layer at interface.

Carbon nanotubes have been the subject of extensive research during the past decade because of their exceptional properties. These tiny nanostructures have eventually paved their way into the exciting and promising field of organic electronics, which is expected to dominate the area of low cost and flexible electronics in the near future. We have prepared multiwall carbon nanotube (MWNT) and poly(3,4-ethylenedioxythiophene):poly(styrenesulphonic acid) (PEDOT:PSS) based nanocomposites using different concentrations of MWNTs. These nanocomposites have been characterized using SEM, AFM, absorption spectroscopy, and electrical characterization methods. The SEM micrographs clearly reveal that the nanotubes are quasi uniformly dispersed in huge quantities throughout the polymer matrix. They also show the wetting of the nanotubes by the polymer. It is observed that the solution processed MWNT–PEDOT:PSS nanocomposite based films exhibit improved, higher current, and lower turn-on voltage as compared to pure PEDOT:PSS based films. On the basis of percolation theory, a low electrical percolation threshold value of 0.1 wt% was obtained for this nanocomposite system, signifying the formation of a continuous conductive network at a very low MWNT concentration. The ease of fabrication of the nanocomposite (solution processed), higher current, lower turn-on voltage and low electrical percolation threshold value, make it an excellent candidate for flexible electronics applications, which will dominate the electronics scenario in the near future.

In the present work, we discuss the transmittance properties of one-dimensional (1D) superconductor nanocomposite photonic crystals (PCs) in THz frequency regions. Our modeling is essentially based on the two-fluid model, Maxwell–Garnett model and the characteristic matrix method. The numerical results investigate the appearance of the so-called cutoff frequency. We have obtained the significant effect of some parameters such as the volume fraction, the permittivity of the host material, the size of the nanoparticles and the permittivity of the superconductor material on the properties of the cutoff frequency. The present results may be useful in the optical communications and photonic applications to act as tunable antenna in THz, reflectors and high-pass filter.

In this paper, we investigate theoretically the transmission properties of one-dimensional quasi-periodic photonic crystals that containing nanocomposite material in the IR wavelength regions. Our structure is particularly designed using the Fibonacci role. Here, the nanocomposite material is composed of nanoparticles of Ag that are randomly immersed in a host dielectric material of SiO₂. Numerical results are mainly investigated based on the well-known characteristic matrix method. The numerical results show the appearance of many photonic bandgaps due to the multiple periodicities of our structure. Furthermore, the effects of the parameters of the nanocomposite such as the volume fraction, the refractive index of the dielectric material and the size of the nanoparticles have distinct effects on the transmittance characteristics of our structure. Wherefore, the proposed structure could be considered the cornerstone for many applications such as multichannel filters and optical switches.

The structures and magnetic properties of the PP+Fe₃O₄ nanocomposites manufactured by different technological techniques were studied in this work. Polymeric nanocomposite materials based on PP+Fe₃O₄ were obtained by two technological methods: hot pressing and extrusion. Scanning electron microscopy (SEM) and AFM investigations of nanocomposites were carried out for structure analysis. It was found that the distribution of Fe₃O₄ nanoparticles in the polymer matrix for nanocomposites obtained by the hot pressing method is uniform and monodisperse. Compared to this, the heterogeneous and inhomogeneous distribution of nanoparticles in the polymer matrix for the samples that were produced through extrusion method was observed. Furthermore, the nanocomposite samples produced via the extraction method have a lower surface regularity rather than those obtained by hot pressing. M(H) and M(T) studies of polymer nanocomposite samples synthesized through both technological methods were performed. Studies have shown that for relatively low concentrated samples — PP+10% Fe₃O₄, the values of the saturation magnetization were close, but the magnetization of nanocomposites obtained by heat pressing was slightly higher than the other samples. This is because the samples obtained by hot pressing method are characterized by higher uniformity and structure that is called “flat packaging”.

A series of ${\mathrm{\text{TiO}}}_2$-modified Cu coatings were developed via a sol-enhanced electrodeposition process. The effect of ${\mathrm{\text{TiO}}}_2$ sol on the properties of fabricated ${\mathrm{\text{Cu–TiO}}}_2$ nanocomposites is studied. Phase composition and microstructures of ${\mathrm{\text{Cu–TiO}}}_2$ deposits were characterized using X-ray diffraction (XRD), atomic force microscopy (AFM) and transmission electron microscopy (TEM). Mechanical properties of the fabricated ${\mathrm{\text{Cu–TiO}}}_2$ coatings were also examined. The proper addition of ${\mathrm{\text{TiO}}}_2$ sol gives rise to refined coating surface with well-distributed ${\mathrm{\text{TiO}}}_2$ nanoparticles, leading to significantly enhanced properties. The microhardness and wear resistance of the ${\mathrm{\text{Cu–TiO}}}_2$ nanocomposite coating (12 mL/L ${\mathrm{\text{TiO}}}_2$ sol) upsurges owing to the strengthening effect of highly dispersed ${\mathrm{\text{TiO}}}_2$ nanoparticles. We also suggest that the excessive addition of ${\mathrm{\text{TiO}}}_2$ sol should be avoided as it will result in an inferior coating quality with a loose structure for the prepared ${\mathrm{\text{Cu–TiO}}}_2$ deposits.

Graphene-Nickel Oxide (G-NiO) nanocomposites with different morphologies, such as nanowires (NWs), nanorods (NRs) and nanoparticles (NPs), are synthesized by a combination of liquid-phase exfoliation (LPE) and hydrothermal methods. The synthesis of Graphene, morphology of Nickel Oxide (NiO) thin films and concentration of elements are analyzed using Raman Spectroscopy, Field Emission Scanning Electron Microscopy (FESEM) and Energy-dispersive X-ray spectroscopy (EDS), respectively. Furthermore, the capacitive behavior of nanocomposites is investigated using the Cyclic Voltammetry (CV). The optical properties of samples are extracted from measured absorbance spectra. Our results show that G-NiO NWs with the longest length have the largest specific capacitance (SC). In addition, optical data revealed that the adding Graphene to NiO thin films decreased the optical bandgap as well as the optical conductivity of nanocomposites increased with photon energy due to excitation electrons.

In this work, the structure, dielectric and optical properties of PVDF/zirconia-based polymer nanocomposites were investigated. The morphology and structure of the nanocomposites were analyzed by XRD, SEM, FT-IR, UV and EDS analyses. It was determined that the forbidden gap for the PVDF/1%ZrO₂-based nanocomposite is 4.7eV, for PVDF/5%ZrO₂-4.5eV, and for PVDF/10%ZrO₂-4.2eV. It is shown that the dielectric permittivity of the nanocomposites increases sharply up to 3% of ZrO₂ nanoparticles in the polymer and then decreases slightly with an increase in the concentration of nanoparticles. An increase in the permittivity indicates an increase in polarization processes in nanocomposites at a 3% conentration of ZrO₂ nanoparticles in the PVDF matrix. It has been established that the dielectric loss tangent at low frequencies starts to decrease, and at high frequencies, it increases. The increase in the dielectric loss tangent at high frequencies is explained by an increase in relaxation processes and energy dissipation in these systems.

This study addressed the preparation of nanocomposites consisting of polyvinyl alcohol (PVA) and titanium oxide (TiO₂) for utilization in optoelectronics technologies. PVA/10%TiO₂ nanocomposite samples with a mean thickness of 0.1mm were created using the solution casting method. The PVA/TiO₂ films are irradiated with oxygen fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm². The X-ray diffraction (XRD) and FTIR methodologies were employed to investigate the impact of ion bombardment on the structural characteristics and functional groups of PVA/TiO₂ substrates. Diffraction peaks are 20.1° for PVA and 25.4° for TiO₂, indicating the successful PVA/TiO₂ nanocomposite construction. The absorbance (A) of unirradiated and irradiated samples was measured using UV–Vis spectroscopy within a wavelength range of 200–1100nm. Band gaps ($E_g$) were calculated using Tauc’s formula for PVA/TiO₂ films, exhibiting a decrease from 4.56eV for unirradiated PVA/TiO₂ film to 4.16, 3.95 and 3.88eV at ion fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm², respectively. Furthermore, the Ubrach tail has a rise of 1.23eV for unirradiated PVA/TiO₂ to 1.28eV, 1.4eV and 1.77eV for irradiated films with ion fluences of $0.4\times 10^{17}$, $0.8\times 10^{17}$ and $1.2\times 10^{17}$ ions/cm², respectively. Additionally, following ion irradiation, the PVA/TiO₂ absorption edge $E_e$, which was 3.56eV, decreased to 3.48, 3.37 and 3.23eV, with increasing ion beam fluences. This study demonstrated that the optical behaviors of the PVA/TiO₂ films were altered under bombardment, suggesting their potential applicability in optical devices.

In this study, we investigated the effects of nanoclay additives on the electrical and mechanical properties of diglycidyl ether of bisphenol A (DGEBA) epoxy resin. Epoxy-clay nanocomposites were synthesized using organically modified two montmorillonite clays (MMT) with different interlamellar spacing (31.5 Å and 18.5 Å). The electrical and mechanical properties of epoxy-clay nanocopomosites were measured with variation of the amount and type of clay. The nanocomposites were found to be homogenous materials although the nanocomposites still have clay aggregates with increasing nanoclay contents. The dielectric constant showed between 3.2 ~ 3.5 and the dielectric loss showed between 3.2 ~ 5.7% in all nanocoposites. The dielectric strength and tensile strength of the 5 wt% Cloisite 15A added epoxy-oclay nanocomposite were 23.9 kV/mm and 86.7 MPa, respectively.

Nano-B₄C powder whose surface was coated with polyvinylalcohol (PVA) was prepared by using a ball milling mechanical activation process. As-prepared powders exhibit the structure of PVA layer on the surface of nano-sized B₄C and the size of the produced core/shell structured nano-B₄C/PVA particles was in the range of 50 to 200 nm. The sheets of the HDPE composite reinforced by the nano- and micro-B₄C fillers were fabricated by hot pressing following the melt mixing process respectively. The structures of prepared nano-B₄C/PVA powders and the degree of particles dispersion in HDPE were observed by means of X-ray diffraction as well as the SEM/TEM images. It was found that the dispersion of the core/shell structured nano-B₄C/PVA fillers in HDPE was more homogeneous than the surface-untreated micro-B₄C fillers in HDPE.