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In this research, different amounts of Ce-doped ZnO thin films were synthesized using the spray pyrolysis method. Structural, morphological and optical properties of these synthesized films were investigated. In XRD analyses, wurtzite (hexagonal) structures were observed in the films. In SEM analysis, there were changes in the surface morphology of the films with doping, and in cross-section measurement, the thickness of the films was measured to be approximately 1.2 μm. In UV–vis spectrometry analysis, it is seen that the effect of Cerium contribution on optical transmittance and band gap positively affects shielding. NaI(Tl) detector and gamma energies of 384, 1173, and 1333 keV have been used to investigate the radiation protection properties of these synthesized films. As a result of these measurements, linear attenuation coefficient (LAC) values have been obtained. Radiation shielding parameters have been calculated with these (LAC) values. The Mass Attenuation Coefficient (MAC), Half Value Layer (HVL), Tenth Value Layer TVL (and) Mean Free Path (MFP) values have been also calculated using this LAC result. According to these results, Ce-doped ZnO films were found to be effective in radiation shielding. • In this article, the effect of cerium doping ratio to ZnO on radiation shielding was examined. • Thin films were produced using the spray pyrolysis technique. • In experiments on radiation shielding properties, 133Ba 384 keV, 60Co 1173 keV and 60Co 1333 keV energy gamma rays were used. • It was determined that the increase in the Cerium rate had a positive effect on radiation shielding. • It was observed that cerium doping affected the energy band gap. [ABSTRACT FROM AUTHOR]

In this research work, a simple spray pyrolysis method was employed to synthesized gadolinium (Gd) doped titanium oxide (TiO2) thin film. The crystal structure and morphology of the sample was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). According to XRD measurements, no apparent crystal peak was observed. The thickness of the prepared film was found to be 228 nm from SEM observation. The optical transmittance and bandgap energy of the synthesized thin film was investigated by using UV-Vis spectroscopy. The high transmission of the thin film was found in the visible region. The optical bandgap energy of the prepared film was found to be 2.85 eV. The photocatalytic degradation of malachite green solution was studied. As a result of the photocatalytic experiment, the thin film could be used as an effective photocatalyst for malachite green dye. [ABSTRACT FROM AUTHOR]

In this study, iron oxide, nickel oxide, and nickel-iron oxide nanostructured particles were produced by the hydrothermal method. X-ray diffraction (XRD) and SEM measurements were performed to investigate the physical properties of these nanostructured particles. According to the XRD results, the crystal properties of these particles were determined. From the SEM images, these particles understood to be nano-structured. The electrodes were examined for electrochemical properties by using these nanostructured particles. Electrochemical measurements of the produced electrodes were performed, and capacitance values and impedance spectra of the electrodes were determined. The specific capacitance values of the iron oxide, nickel-iron oxide, and nickel oxide nanostructured particles, respectively are 30 F/g, 55 F/g, and 67 F/g. Also, the photocatalytic activities of nanostructured particles were investigated. This examination methylene blue (MB) was used and made under a xenon lamp. In light of our findings, it was observed that high photocatalytic degradation rate. Nickel-iron oxide nanostructured particles, the degradation of MB were found to be about 87%. [ABSTRACT FROM AUTHOR]

In this study, iron oxide, nickel oxide, and nickel-iron oxide nanostructured particles were produced by the hydrothermal method. X-ray diffraction (XRD) and SEM measurements were performed to investigate the physical properties of these nanostructured particles. According to the XRD results, the crystal properties of these particles were determined. From the SEM images, these particles understood to be nano-structured. The electrodes were examined for electrochemical properties by using these nanostructured particles. Electrochemical measurements of the produced electrodes were performed, and capacitance values and impedance spectra of the electrodes were determined. The specific capacitance values of the iron oxide, nickel-iron oxide, and nickel oxide nanostructured particles, respectively are 30 F/g, 55 F/g, and 67 F/g. Also, the photocatalytic activities of nanostructured particles were investigated. This examination methylene blue (MB) was used and made under a xenon lamp. In light of our findings, it was observed that high photocatalytic degradation rate. Nickel-iron oxide nanostructured particles, the degradation of MB were found to be about 87%. [ABSTRACT FROM AUTHOR]

• Synthesis of silver-doped reduced graphene oxide/Pani composite. • Electrochemical measurements of silver-doped reduced graphene oxide/Pani composite. • Supercapacitor analysis of silver-doped reduced graphene oxide/Pani composite and coin cell application. In this study, graphene oxide was synthesized by the Hummers method. Reduced graphene oxide was obtained by the hydrothermal method. Then, silver-doped Reduced Graphene Oxide/Polyaniline (Ag-doped rGO/PANI) composites were synthesized. Some physical analyzes of the synthesized composite materials were made. In the XRD examination, it was understood that the materials generally have polyaniline properties. Electrochemical properties were investigated with electrodes prepared from these composites. Specific capacitance, energy, and power density values were calculated from these measurements. The specific capacitance was measured in the range of 0.5–30 A/g and the highest capacitance value was found to be 379 F/g. From these results, the material containing approximately 17 mass percent silver doped reduced graphene oxide gave better results among composite materials. This composite was the most stable material with results of 286–317 F/g at all applied currents. In addition, a coin cell application was made for this example and its measurements were taken. [Display omitted] [ABSTRACT FROM AUTHOR]

Boron doped vanadium thin films were fabricated on the micro-slide glass substrates by spray pyrolysis technique at substrate temperature of 400°C. Initially, 0.1 M vanadium(III) chloride (VCl3) solution was prepared in ethanol: water mixture (1: 4) solvent. To prepare the boron doped vanadium oxide films as the concentrations of 2, 5, 7, 10, 20%, the suitable amount of H3BO3 was added in 0.1 M VCl3 solution for each of the samples. X-Ray diffraction experiment with the produced films showed that tetragonal β-V2O5 phases formed. The synthesized boron-doped V2O5 thin films having the large surface area demonstrated the efficient catalytic properties in the photocatalytic degradation of methyl blue in water samples under Xenon light. The photocatalytic reaction efficiency was measured by recording the decrease of absorbance at 590 nm in UV-Vis absorption spectra. The methyl blue dye was degradated in approximately 30 min. The photocatalytic experiment results of the produced thin films showed that boron doping amount positively effects the degradation efficiency and reaction time. [ABSTRACT FROM AUTHOR]

Fluorine-doped ZnO (FZO) thin films were fabricated on glass substrates using a chemical spray pyrolysis method for NO 2 gas detection. The physical properties of the films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and ultraviolet–visible (UV–Vis) spectrometry as a function of fluorine concentration (2 and 5 at%). The films exhibited a hexagonal wurtzite structure, and the inclusion of fluorine did not significantly influence the morphology of the films. Optical measurements showed that the band gap energies of the films were affected by the fluorine concentration. Furthermore, the NO 2 gas-sensing properties of pristine and FZO thin films were investigated in the concentration range of 100–1000 ppb. Fluorine doping in ZnO was found to improve the NO 2 -sensing capability at the least. All gas sensor measurements showed an optimal sensor response at a temperature of 200 °C. In addition, the 2% FZO was found to be more suitable candidate for detecting NO 2 gas. [ABSTRACT FROM AUTHOR]

Blue fluorescent carbon dots are synthesized via a one-step hydrothermal method using rosemary leaves as a carbon source. The obtained carbon dots are characterized by X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, UV-Vis, FTIR, and fluorescence spectrometry. The results show that carbon dots gave a maximum emission peak at 422 nm when excited at 332 nm. The average particle diameter of the synthesized spherical carbon dots is found to be 16.13 nm with a 4.6-nm standard deviation. The diameters of the produced carbon dots vary, as is evident from standard deviation heights, resulting in multicolor emission spectra. The fruit storage experiment is carried out by investigating the qualitative antioxidant ability of the produced carbon dots. The results obtained for polyvinyl alcohol–carbon dot–coated samples differ remarkably compared to polyvinyl alcohol–coated samples only. The polyvinyl alcohol–carbon dot composition is used in latent fingerprint detection applications. In analyses made on a glass surface, fingerprints cannot be monitored on the glass surface with the polyvinyl alcohol layer under ultraviolet light, while they are observed on the surface covered with the polyvinyl alcohol–carbon dot composition. Moreover, biological activity against Gram-positive, Gram-negative, and yeast strains are investigated. [ABSTRACT FROM AUTHOR]

In this study, vanadium pentoxide (V2O5) nanoparticles were synthesized by hydrothermal method. The structural and morphological properties of obtained nanoparticles were examined using X-ray diffractometer, scanning electron microscopy and transmission electron microscopy. The optical properties of produced nanoparticles have been investigated by fluorescence spectrometer. The produced V2O5 nanoparticles showed an emission peak at 378 nm when excited at 314 nm. The characterized V2O5 nanoparticles dispersed to nematic liquid crystals mixture E7. Threshold voltage, dielectric anisotropy values of pristine E7 and V2O5 nanoparticles dispersed samples have been investigated using impedance analyzer. The phase transitions and microstructural properties of the prepared nanoparticle dispersed liquid crystalline complexes were investigated by differential scanning calorimeter and polarized optical microscopy. Moreover, splay elastic constant and order parameter of the samples were calculated. The synthesized V2O5 nanoparticles were aggregated for 0.5% V2O5 dispersed samples after 30 days were found. Dielectric measurements revealed that the dielectric anisotropy slightly decreased with the dispersion of V2O5 nanoparticles. [ABSTRACT FROM AUTHOR]

Purpose of this study is to investigate effect of gadolinium (Gd) content of GdxFe2O3(100-x), (x = 0, 5, 10, 20) composite system on structural, thermal, optical and radiation protection of poly (vinyl alchool) PVA based nanocomposite film. In this study, Gd doped Fe 2 O 3 nanopowders (with Gd = 0, 5, 10 and 20) were synthesized by spray pyrolysis method. The characterization of these powders have been obtained by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and Uv–vis spectrometer. After then, GdxFe 2 O 3 (100-x)/PVA (x = 0, 5, 10, 20) polymer composite systems were prepared by solution casting technique. The structural, thermal and optical properties of obtained polymer composites have been examined. The irradiation properties of 6 MeV energized X-ray via cLINAC to obtain radiation shielding performance of these different percentage (0, 5, 10, and 20%) Gd doped Fe 2 O 3 PVA thin films were also investigated. By using obtained results, the Linear Attenuation Coefficient (LAC), Half Value Layer (HVL), Tenth Value Layer (TVL), Mass Attenuation Coefficient (MAC). Also, theoretically Z eff value have been calculated. According to all obtained results, it has been seen that the different percentages (0, 5, 10, and 20%) Gd doped Fe 2 O 3 PVA thin films can be used as radiation shielding material. • Purpose of this study is to investigate effect of gadolinium (Gd) content of GdxFe2O3(100-x), (x=0, 5, 10, 15, 20) composite system on structural, thermal, optical and radiation shielding of poly (vinyl alchool) PVA based nanocomposite film. • The characterization of these powders have been obtained by using X-ray diffractometer (XRD), scanning electron microscopy (SEM), and Uv–vis spectrometer. • The irradiation properties of 6 MeV energized X-ray via cLINAC to obtain radiation shielding performance. • By using obtained results, the Linear Attenuation Coefficient (LAC), Half Value Layer (HVL), Tenth Value Layer(TVL), Mass Attenuation Coefficient(MAC). • Also, theoretically Zeff values have been calculated. [ABSTRACT FROM AUTHOR]

Yttrium oxide (Y2O3) nanoparticles have very wide application areas such as biological imaging, photodynamic therapy, the material sciences, in the chemical synthesis of inorganic compounds, additives in plastic, paint, steel, optics, and iron. Potential risks to human health and the environment should be evaluated in a multi-dimensional perspective when developing nanoparticles for those applications. Therefore, in this research, we aimed to investigate changes in gene expression profiles (genes involved in different biological pathways) influenced by commonly Yttrium oxide (Y2O3) nanoparticle in human U87MG glioma and PC3 prostate cancer cell lines in vitro. The study was planned to be carried out in two stages. In the first stage, cell viability and cytotoxicity parameters were studied using 3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide and lactate dehydrogenase release assays, respectively, with human U87MG glioma and human PC3 prostate cancer cell cultures. In the second stage, to obtain a clear insight into the molecular events after exposing, we examined the effects of selected Y2O3 nanoparticle on the expression of genes in U87MG and PC3 cell cultures using RT² Profiler PCR Arrays. Y2O3 nanoparticles have IC20 of 0,18 mg/L and 2,903 mg/L in PC3 and U87MG cell lines, respectively. Y2O3 nanoparticle induced up-regulation of 24 and down-regulation of 22 genes in PC3 cells and up-regulation of 53 and down-regulation of 27 genes in U87MG cells. This study of gene expression profiles affected by nanotoxicity provides critical information for the clinical and environmental applications of Y2O3 nanoparticles. [ABSTRACT FROM AUTHOR]

In recent years, the production of alternative materials instead of lead in the environmentally sensitive and non-toxic material research in radiation shielding has been gained importance. In this study, transparent pristine and boron (B) doped zinc oxide (ZnO) thin films were synthesized by spray pyrolysis method. The crystalline structure, morphology and optical properties of the produced films were investigated with X-ray diffractometer (XRD), scanning electron microcopy (SEM) and Uv–vis spectrometer. The wurtzite structure of pure ZnO was deformed by boron doping found from XRD results. The hexagonal rods have been worsened with boron doping observed from SEM analysis. The factors related to radiation shielding; mass and linear attenuation coefficients, half value layer, mean free path and tenth value layer of different percentage (5, 10 and 20%) B doped ZnO thin films were examined. To perform these measurements, PTW® electron detector and irradiation have been utilized with 6 MeV energized electrons by using VARIAN®. The obtained results from these measurements can be useful to understanding of radiation shielding performance of ZnO:B thin films. • Pristine and boron doped zinc oxide thin films were synthesized by pyrolysis methods. • Optical transmittance of the prepared films were enhanced as a function of boron concentration. • The linear attenuation coefficient increased as the percentage of boron in the thin films increased. • ZnO: B thin films can be used as radiation shielding with different materials in radiation treatment centers. [ABSTRACT FROM AUTHOR]

We present the thermal and optical properties of binary mixtures formed from hydrogen-bonded liquid crystal 4-hexylbenzoic acid (6BA) and 4-hexyl-4′-biphenylcarbonitrile (6CB) mesogens. Phase transition temperatures and enthalpy values are evaluated by differential scanning calorimetry (DSC) and phases identified by polarized optic microscopy (POM). The experimental results obviously show that the 6BA/6CB binary mixtures exhibit nematic and smectic phases. The most interesting result is that although the smectic phase is not observed in pure components 6BA and 6CB, it is observed in their some binary mixtures. The thermal properties like phase peak temperatures, enthalpy changes and thermal span of binary mixtures are affected by depending on the mixture ratio. The nematic range increase in the binary mixture compared to the individual mesogen, and also the phase transition temperature values and the nematic thermal stability factor increase as heating rate increases. Furthermore, the calculated activation energy values show that the reorientation of the molecules during the phase transitions of the mixture occurs on an orderly basis. [ABSTRACT FROM AUTHOR]

Yttrium oxide nanoflowers were prepared by a hydrothermal technique, and X-ray diffraction and scanning electron microscopy were used to determine their structures. The cytotoxic and genotoxic potentials of aqueous dispersions of the nanoflowers to cultured primary rat hepatocytes were examined at concentrations up to 500 mg L−1for 72 h. Cell viability was determined by monitoring the reduction of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, release of lactate dehydrogenase, and uptake of neutral red. Genotoxicity was assessed by the liver micronucleus assay. Exposure to Y2O3nanoflowers at concentrations lower than 100 mg L−1did not lead to any cytotoxicity or genotoxicity. At higher concentrations (200, 400, and 500 mg L−1), cell viability decreased and induction of micronuclei increased (400 and 500 mg L−1). [ABSTRACT FROM PUBLISHER]