Transparent films of polyvinyl alcohol/polyethylene glycol (PVA/PEG) blend loaded with different nano-silica (SiO 2 ) content were prepared by using solution casting. The effect of SiO 2 nanoparticle loading on the optical properties of selected PVA/PEG blend ratio is studied in the spectral region 200-700 nm. The present study monitors the changes in the optical dispersion parameters such as band tail width, extinction coefficient, refractive index, and optical dielectric constant calculated as a function of nano-silica content. The results revealed that the obtained optical parameters were strongly affected by the SiO 2 content in the blend films. Also, Cauchy model is used to fit the wavelength dependence of the refractive index of the composites. In addition, thermogravimetric analysis indicates the increase of thermal stability of the composites with respect to pure blend. The Coats and Redfern model is used to calculate activation energies for decomposition.

A solvent thermal method which depends on a thermal process under critical temperature and pressure was used to prepare cobalt iron oxide magnetic nanoparticles with a molar ratio 2. The prepared particles were in the form of nanoparticles with diameter ranging from 5 to 10 nm and with amorphous structure. Magnetic hysteresis behavior with saturation magnetization 36.31 emu/g and coercivity 4 Oe were observed for the nanoparticles. Polyvinyl alcohol was loaded with different concentrations of cobalt iron oxide nanoparticles using casting technique. Hysteresis loops for the polymer films were observed and both the saturation magnetization and coercivity were increased from 0.36 to 16.03 emu/g and 115 to 293 Oe for samples containing 5 and 20 wt% of nanoparticles, respectively. The elastic modulus of films was increased from 2.7 to 4.9 GPa for unloaded and loaded samples with 20 wt%, respectively. The storage modulus of the polymer films was found to obey the percolation behavior.

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PET/CT in paediatric head and neck carcinoma is more accurate than conventional imaging. Therefore, it also has a significant impact on further patient management. We recommend that it should be the first imaging modality for all purposes in initial staging, evaluating treatment response and follow-up in paediatric head and neck carcinoma.

The present study aims to prepare a low-cost, eco-friendly, free-standing film with optimized physical properties. A PVA composite of hard-soft hybrid filler ratio 1:3 (nSiO2:Gl) is prepared by casting. Dynamic mechanical analyses are processed in the frequency range (0.01–9 Hz). Moreover, dielectric studies are performed in the frequency range (50 Hz–5 MHz). Herein, the modified Jonscher equation and electric modulus formalism are used to explain the results. Transmittance and reflectance of studied samples are measured in the UV–Vis range (200–700 nm). Detailed discussions of band structure, refractive index, and optoelectronic parameters are addressed. Remarkably, the results showed that mechanical and electrical properties of PVA can be tuned by careful modulation of glycerol content, whereas optical properties are more sensitive to nSiO2 content. Finally, FTIR and SEM structural analyses investigate the induced structural changes in PVA.

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A novel Schiff base ligand (L) was prepared through condensation of 2,6-diaminopyridine and dibenzoyl methane in a 1:1 ratio. This Schiff base ligand was used for complex formation reaction with Fe(III) chloride. The structures of the ligand and its complex were deduced from elemental analyses, mass spectroscopy, 1 H NMR, IR, UV-Vis, electronic spectra, magnetic moment, molar conductivity measurements, thermogravimetric analyses and X-ray diffraction. The molecular and electronic structures of both ligand and complex were optimized theoretically using density function theory (DFT) method.Moreover, the antimicrobial activities of the prepared compounds were studied and proven against some pathogenic bacteria. The Fe(III) complex had higher biological activity than that of the free ligand. Proceeding from the collected information, the properties of the complex were further investigated. The particle size was determined by dynamic light scattering technique to be 92.59 nm.Textural properties of the nano complex were studied by N 2 adsorption to estimate the specific surface area, pore volume and pore size distribution. The pores in the complex were found in the micropore-mesopore range. Differential scanning calorimetric measurements reveal the existence of four endothermic peaks at 243.8, 308, 339.8 and 380.5 K. Dielectric properties and conductivity were scanned at different frequencies and temperatures. The dielectric constant reaches a peak value of 600 at~390 K, 30 Hz. A crossover from the universal dielectric response to the super linear power law of conductivity was reported for this complex at T ≤ 345 K. Finally, the ACmagnetic susceptibility measurements were carried out in the lowtemperature region. The complex showed paramagnetic behavior with a slight change in the magnitude of its magnetic moment at T = 244 K.

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