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An environmentally safe chemical process was used to create the CdSe nanocomposite films in a polyvinyl alcohol (PVA) matrix. X-ray diffraction was used to analyze these composites, revealing the cubic zinc blend structure of CdSe/PVA nanocomposite with crystal sizes as small as a few nm. These composite films have had their photoluminescence (PL) properties examined. At 420nm, the PL peak of CdSe/PVA was detected. The CdSe/PVA nanocomposite’s mechanoluminescence properties were investigated. It is found that the impact velocity determines the ML intensities. When ML is produced impulsively by the impact of a moving piston on the nanocomposite, two peaks in ML intensity arise with time, and it is found that the mechanoluminescence intensity is dependent on the magnitude of impact velocity. ML peak intensities of the first and second peaks ($I_{m1}$ and $I_{m2})$ increase with increasing impact velocity. However, the time corresponding to the first and second maxima ($t_{m1}$ and $t_{m2})$ shifts towards shorter time values with greater impact velocity. We examined the voltage-brightness and voltage-current characteristics curves for our electroluminescence investigations of CdSe/PVA nanocomposite. At higher frequencies, EL with greater brightness at low threshold voltage has been seen.

Perovskite solar cells have higher efficiency and low cost as compared to other available commercial solar cells however due to large advantages it is not available commercially because it has very low stability which is nearly equal to one year. So to enhance the stability, different types of Cs-based optimized hybrid nanocomposites are used. Sol–gel and hydrothermal methods were used to prepare the Cs-nanocomposites. The crystallinity, surface morphology, elemental composition, thermal stability and nanocomposites’ absorbance were observed using X-ray diffraction, scanning electron microscope, energy dispersive X-ray, thermo gravimetric analysis, ultraviolet-visible (UV–Vis) and Raman spectroscopy techniques. This research work consents successfully for the synthesis of nanocomposites and enhancement in stability of perovskite substantial-based absorber layer. During analysis of TGA, only 2.5% of the weight of Cs-nanocomposites lost their total weight and J-V properties such as $J_{\mathrm{\text{sc}}}$ and power conversion efficiency of PSCs remarkably increased by nearly 3mAcm${}^{-2}$ and 4%, respectively by using Cs-based NCs.

In this research work, nanocomposites of CuO/TiO₂ were initially fabricated using drop casting method. Later on, these nanocomposites were irradiated for the first time by a beam of Argon ions (Ar${}^{+})$ by keeping the fluence rates of $1\times 10^{14}$ ions cm${}^{-2}$, $1\times 10^{15}$ ions cm${}^{-2}$, and $1\times 10^{16}$ ions cm${}^{-2}$, respectively. In order to observe structural and optical properties of un-irradiated and irradiated nanocomposites, Raman Spectroscopy, Energy Dispersive X-ray (EDX), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), Photoluminescence (PL) and Diffuse Reflectance Spectroscopy (DRS) analysis were performed. From Raman analysis, vibration modes confirmed the presence of different phases of TiO₂ and CuO. EDX analysis clearly demonstrates the presence of Cu, Ti, and O peaks. SEM images depict agglomerated spherical nanoparticles having diameters in the range of 40–94nm. From TEM analysis, mean diameter of 56.1nm is observed for unirradiated and 33.7nm for Ar${}^{+}$ irradiated CuO/TiO₂ nanoparticles in nanocomposite for fluence rates of $1\times 10^{14}$ ions cm${}^{-2}$, $1\times 10^{15}$ ions cm${}^{-2}$, and $1\times 10^{16}$ ions cm${}^{-2}$. HR-TEM and SAED images represent the polycrystalline nature of these nanocomposites.

Among the three peaks of PL spectra in UV–Visible region, first two peaks were observed at 356nm, and 419nm but the third peak is little shifted from 488nm with the increase in fluence rate. Values of band gap are reduced from 3.29eV to 3.17eV as the fluence rate is increased, as calculated from results of diffuse reflectance spectroscopy.

Curved nanobeams are one of the essential components in manufacturing nano-electromechanical systems needing nonlinear stability design. In the current investigation, the nonlinear buckling characteristics of functionally graded porous reinforced curved (FGPRC) nanobeams having different degrees of curvature are analyzed by counting the higher-order gradients of the classical strain tensor as well as nonlocal-type interatomic interactions. In this regard, two independent length-scale constants within the framework of the nonlocal strain gradient theory (NSGT) of continuum elasticity are taken into account. Via employing the promising low computational cost and geometrically adaptable method of isogeometric collocation, various branches of NSGT-based equilibrium graphs of FGPRC nanobeams are plotted relevant to each considered degree of curvature. It is extrapolated that the quantity of graphene platelet (GPL) weight fraction has a negligible influence on the significance of nonlocal-type of interatomic size dependency as well as the strain gradient kind of small-scale effect in the value of the maximum deflections or lateral loads at the detected limit points, especially attributed to a higher degree of curvature. Besides, it can be remarked that, in the FGPRC nanobeam owning a small degree of curvature, lessening the quantity of porosity index results in an increment in the significance of the nonlocal-type of interatomic size dependency as well as the strain gradient kind of small-scale effect on the maximum deflection at both upper and lower limit points. However, in the FGPRC nanobeams owning medium and large degrees of curvature, it gets lesser at the upper limit point, but becomes higher at the lower limit one.

This paper primarily refers to the nonlinear instability of functionally graded porous (FGP) egg-shaped subsea pipelines mixed with graphene platelets (GPLs) under pressure and thermal environments. The FGP-GPLs egg-shaped subsea pipeline deflects radially inward since the pipeline is confined tightly and rigidly by the medium (soils/rocks). This deflection may be represented by a refined available displacement formula. The response curves are effectively traced by associating the computational calculus and the thin-walled shell theory. Furthermore, numerical verifications are completed to validate the analytical schemes. It is seen that the numerical curves are closely fitted to the theoretical ones. Moreover, the current study is validated efficiently by other results. Finally, evaluations are conducted on some parameters that affect the instability of the FGP-GPLs subsea pipeline with an egg-shaped profile, including the porosity coefficient, geometric shapes, weight fraction, temperature variations, etc.

PVA/CdS nanocomposites were obtained by forming cadmium sulfide (CdS) nanoparticles by the layered chemisorption method of anions and cations from a solution of appropriate salts in the pores of polyvinyl alcohol (PVA). A comparative analysis of optical and electrical properties of pristine and gamma-irradiated PVA/CdS nanocomposites was performed. It has been shown that the observed changes in the optical and electrical properties of gamma-irradiated PVA/CdS nanocomposites are the result of a change in the ratio between the construction and destruction processes occurring in the matrix and at the polymer-filler interphase boundary. We believe that the reason why the value of the forbidden zone determined from the optical properties of the original and irradiated PVA/CdS nanocomposites shifts from 6eV for PVA to 2.6eV with the increase in the number of formation cycles in nanocomposites is the change in the size of CdS nanoparticles. The reason for the changes in the value of the $E_g$ parameter of nanocomposites with the increase of the dose of gamma radiation is the change in the relationship between the interaction between components and the construction-destruction processes at the polymer-filler interphase boundary, as can be seen from the dependences of $E_g=f(D)$. The reason for the changes in the electrical properties of PVA/CdS nanocomposites is the change in the mobility of the macromolecular chains of the matrix due to the changes that occur at the interphase boundary after gamma irradiation. The results of the study show that the optical and electrical properties of nanocomposites can be controlled by choosing the number of forming cycles and the value of the gamma radiation dose.

Silk films prepared from regenerated silk fibroin are normally stabilized by β-sheet formation through the use of solvents (methanol, water etc.). Herein, we report a new method of preparing water-stable films without a β-sheet conformation from regenerated silk fibroin solutions by incorporating a small amount (0.2 wt%) of multiwalled carbon nanotubes (MWCNTs). To extend the biomaterial utility of silk proteins, forming water-stable silk-based materials with enhanced mechanical properties is essential. Scanning electron microscopy and transmission electron microscopy were used to observe the morphology of the MWCNT-incorporated silk films. The wide-angle X-ray diffraction provided clear evidence of the crystallization of the silk fibroin induced by MWCNT in the composite films without any additional annealing processing. The tensile modulus and strength of the composite films were improved by 108% and 51%, respectively, by the incorporation of 0.2 wt% of MWCNTs, as compared with those of the pure silk films. The method described in this study will provide an alternative means of crystallizing silk fibroin films without using an organic solvent or blending with any other polymers, which may be important in biomedical applications.

Gelcasting process as a promising method for fabrication of reliable ceramics has been utilized to develop alumina-zirconia nanocomposites from nanosized powders. Sedimentation and viscosity measurement were performed to find the accurate dispersing condition for production of alumina-zirconia nanocomposite slurry with high solid loading and low viscosity. The gelcasting was accomplished by in situ polymerization of an acrylamide base monomer. The effects of solid loading, viscosity and deairing were also studied. Finally, crack and flaw free samples with relative densities of 99%, were achieved from the optimal slurry with 35vol. % solid loading, by performing sintering at 1600°C for 2 hours. SEM micrographs showed dense microstructure with fine and homogenous dispersion of zirconia phase in the alumina matrix.

Composites of polyaniline with synthesized nanostructured titania (TiO₂) and polyaniline with commercial TiO₂ have been in situ synthesized by oxidative chemical polymerization method. Sulfuric acid was used as dopant during the polymerization process. Sol-gel precipitates of nanostructured titania were synthesized by hydrolyzing the mixture of titanium chloride (TiCl₃) and colloidal transparent solution of starch. Composite materials were subjected for comparison to spectroscopic and X-ray diffraction analysis. Strong coupling/interaction of titania with the imine nitrogen in polyaniline confirmed by FTIR spectral analysis. XRD shows the composite of synthesized titania with polyaniline have broaden peak as compared to that of commercial titania with polyaniline indicating particle size in the range of nanometer scale which is supported by 40 nm particle size of the synthesized titania from TEM picture. Increase in conductivity with increasing temperature was observed in both the composite materials.

We study the noise spectra and high-frequency permeability of inhomogeneous magnetic materials consisting of single-domain magnetic nanoparticles embedded into an insulating matrix. Possible mechanisms of 1/f voltage noise in phase-separated manganites is analyzed. The material is modelled by a system of small ferromagnetic metallic droplets (magnetic polarons or ferrons) in insulating antiferromagnetic or paramagnetic matrix. The electron transport is related to tunnelling of charge carriers between droplets. One of the sources of the 1/f noise in such a system stems from fluctuations of the number of droplets with extra electron. In the case of strong magnetic anisotropy, the 1/f noise can arise also due to the fluctuations of the magnetic moments of ferrons.

The high frequency magnetic permeability of nanocomposite film with magnetic particles in insulating non-magnetic matrix is studied in detail. The case of strong magnetic dipole interaction and strong magnetic anisotropy of ferromagnetic granules is considered. The composite is modelled by a cubic regular array of ferromagnetic particles. The high-frequency permeability tensor components are found as a functions of frequency, temperature, ferromagnetic phase content, and magnetic anisotropy. The results demonstrate that magnetic dipole interaction leads to a shift of the resonance frequencies towards higher values, and nanocomposite film could have rather high value of magnetic permeability in the microwave range.

This paper presents recent studies on the processing and characterization of epoxy-alumina nanocomposites. Nano-sized alumina particles are incorporated into epoxy resin via solvent-assisted method, so that the particles are dispersed homogeneously in the epoxy matrix. The morphologies, mechanical and thermomechanical properties of the resulting nanocomposites are studied using transmission electron microscope (TEM), conventional tensile testing and thermomechanical testing methods. TEM results show that the alumina nano-particles with a higher specific surface area tend to agglomerate. Furthermore platelet shape particles shows a better dispersion homogeneity as well as better improvement in the mechanical properties of the composites compared to the rod shape particles.

This work reports the preparation of SiO₂ and TiO₂/poly (vinyl butyral) nanocomposites with enhanced dynamic mechanical properties. Silica and titania nanoparticles were introduced in the matrix as the neat powder and as colloidal sol using the melt mixing process. Composites reinforced with colloidal sol silica and titania showed higher mechanical properties than the ones reinforced with as-received particles. When sol TiO₂ particles are used, the highest increase of storage modulus of about 54% is obtained for 5 wt% loading, while for sol SiO₂, the storage modulus increases with the addition of nanosilica with the largest increase of about 99% for 7 wt% loading. In addition, nanocomposites were introduced within Kevlar/PVB composites. The addition of 5 wt% silica and titania colloidal sol lead to the remarkable increase of the storage modulus for about 98 and 65%, respectively. Largest contribution of nanoreinforcements in lowering the glass transition temperature is observed for 7 wt% loading of TiO₂ and SiO₂ colloidal sol.

Antibacterial glass mat sheets containing unsaturated polyester resin as a matrix and poly[2-(dimethylamino)ethyl methacrylate] (PDMAEMA)-functionalized multi-walled carbon nanotube (MWNT) nanocomposites as a filler were prepared. Controlled functionalization of MWNT by in situ atom transfer radical polymerization (ATRP) of DMAEMA was applied for the preparation of nanocomposites. An antibacterial activity of the prepared unsaturated polyester glass mat sheets was determined by the application of film contact method based on the Japanese Industrial Standard JIS Z-2801. The mechanical properties of the prepared unsaturated polyester glass mat sheets were estimated by the simplified procedure designed in laboratory. A deliberate search for the ATRP process conditions showing the most effective antibacterial activity was tried beyond all experiments.

The effects of carbon nanotubes (CNTs) on mechanical and tribiological properties of the NiFe/CNT composites prepared by high energy mechanical alloying and hot pressing, were investigated. Bulk samples were prepared by sintering of cold pressed (300 MPa) samples at 1040°C for 1 h. X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and optical microscopy were employed for evaluation of the phase composition, surface morphology and porosities of the samples. The microhardness of as-milled Ni₃Fe and NiFe powders reached to 720 and 650 VHN, respectively. The hardness of NiFe and Ni₃Fe bulk samples reduced to 190 and 270 Vickers because of the grain growth during sintering and remaining porosity. The hardness of NiFe-CNT and Ni₃Fe-CNT bulk samples reached to 360 and 400 Vickers, respectively. The friction and wear properties of the bulk samples were investigated under dry conditions using a pin-on-disk test rig under an applied load of 8 N. The wear rate, mass loss and friction coefficient of the composite samples remarkably reduced in comparison with NiFe and Ni₃Fe matrix alloys which demonstrate effects of the CNTs on mechanical and tribiological behavior of the composites resulting from the excellent mechanical properties and unique topological structure of the CNTs.

Cross-linked polyvinyl alcohol (PVA) graphene oxide (GO) nanocomposites were prepared by simple solution-mixing route and characterized by Raman, UV–visible and fourier transform infrared (FT-IR) spectroscopy analysis, X-ray diffraction (XRD) and scanning electron microscopy (SEM) techniques. The XRD pattern and SEM analysis showed significant changes in the nanocomposite structures, and the FT-IR spectroscopy results confirmed the chemical interaction between the GO filler and the PVA matrix. After these morphological characterizations, PVA-GO-based diodes were fabricated and their electrical properties were characterized using current–voltage (I–V) and impedance-voltage-frequency (Z-V-f) measurements at room temperature. Semilogarithmic I–V characteristics of diode showed a good rectifier behavior. The values of C and G/$\omega$ increased with decreasing frequency due to the surface/interface states (N${}_{\mathrm{\text{ss}}}$) which depend on the relaxation time and the frequency of the signal. The voltage, dependent profiles of N${}_{\mathrm{\text{ss}}}$ and series resistance (R${}_{\mathrm{\text{s}}}$) were obtained from the methods of high-low frequency capacitance and Nicollian and Brews, respectively. The obtained values of N${}_{\mathrm{\text{ss}}}$ and R${}_{\mathrm{\text{s}}}$ were attributed to the use of cross-linked PVA-GO interlayer at the Au/n-Si interface.

This study investigates an analysis of the healing behavior of carbon-based nanocomposites by using the finite element (FE) method and provides the quantitative healing values based on the efficiency with respect to the volume, C${}_h=1-$V${}_{\mathrm{\text{healed}}}$/V${}_{\mathrm{\text{nonhealed}}}$. An approximation of the geometrical relationship on the profile was considered, and the results compared with the model were used to estimate the healing efficiency based on the initial open profiles. In this model, it contains the interface elements between damaged crack faces. We adjust their sizes and stiffness of elements to compare the profiles with a geometrical equation. We propose that the results of their efficiencies can be compared with the strength of the healing elements that depend on the size of healed volume by the approximation.

In this study, halloysite nanotubes (HNTs) were heat-treated at various temperatures in order to minimize particle aggregation, and the mechanical properties in the humid environment was compared and analyzed to prevent the pore formation and achieve an optimal bonding with epoxy resin. As a result, the glass fiber-reinforced plastic (GFRP), with 0.5 wt.% heat-treated HNT at 700${}^{\circ }$C, showed the highest moisture absorption resistance, tensile strength and interlaminar shear strength.

In this paper, we report the safe removal of methyl orange (MO) dye from aqueous solution using chemical interaction of dye molecule with polyaniline/zinc oxide (PANI/ZnO) nanocomposite. PANI/ZnO nanocomposite has been prepared by in situ polymerization. PANI/ZnO nanocomposite was found to be the best promising candidate for adsorption of dyes due to more porosities compared to that of pure PANI. In the present investigation, PANI/ZnO nanocomposite was mixed in a solution of MO dye and used for adsorption process. Color removal was studied using UV-Vis spectroscopy and the spectra were recorded for specific time interval and validation of kinetic model has been applied. Absorbance of PANI/ZnO nanocomposite was found to be increased as compared to that of pure ZnO nanoparticles and pure PANI due to synergistic effect. Comparatively, the removal of dye was also found to be more by using PANI/ZnO nanocomposites. In order to evaluate kinetic mechanism the pseudo-first-order model, pseudo-second-order model and intraparticle diffusion models were verified by the linear equation analysis. Adsorption mechanism of pseudo-second-order model was systematically explained for removal of dye using PANI/ZnO nanocomposite. The results clearly demonstrated that the adsorption mechanism gives very novel and green method of removal of hazardous dyes from waste water.

The multiferroic magnetoelectric materials have gained intensive research interest in the recent years due to their prospective applications. In this perspective, the thermally tunable complex impedance, dielectric behavior and room-temperature magnetoelectric coupling of xCo${}_{0.5}$Ni${}_{0.5}$Fe₂O₄–(1 - x)PbZr${}_{0.58}$Ti${}_{0.42}$O₃ (x = 0.2, 0.3 and 0.5) nanocomposites have been investigated. A series of samples have been prepared by chemical pyrophoric reaction process. The structural characterization confirms the coexistence of two different types of phases, there is no phase segregation. The temperature-controlled complex impedance analysis reveals that grain boundaries and grain of the nanocomposites are playing a dominating role. The existence of Maxwell–Wagner interfacial polarization of the nanocomposites causes a high dielectric constant at low frequency. The calculated AC conductivity values with frequency at different temperatures follow the Jonscher’s power-law. A small polaronic hopping contributes largely to the conduction process of the decorated composite. The magnetostriction properties lead to the AC and DC magnetic field-dependent magnetoelectric coupling of the nanocomposites. The magnetoelectric coupling coefficient depends on the concentration of the piezomagnetic phase of the composites.

In the presented work, nanocomposites based on poly (vinylidene fluoride) (PVDF) and magnetite Fe₃O₄ nanoparticles were prepared. The structure and content of nanocomposite materials were studied by using scanning electron microscope (SEM), atomic-force microscope (AFM) and X-Ray diffraction (XRD). Magnetic properties of PVDF+Fe₃O₄ nanocomposites have been studied upon increasing nanoparticle content in polymer matrix upto 20%, revealing superparamagnetic behavior as Fe₃O₄ nanoparticles in polymer matrix act out like single-domain particles. It has also been observed that PVDF+Fe₃O₄-based nanocomposites can absorb the electromagnetic waves in the high frequency range 0.1–30 GHz. It has been shown that the absorption of high frequency radio waves by PVDF+Fe₃O₄ nanocomposites can be explained by the different molecular structures and also by the scattering of the radio waves at the boundary of nanoparticle-polymer matrix.