Yazar "Ugur, Naz" seçeneğine göre listele

Listeleniyor 1 - 6 / 6
  • [ X ]
    Öğe
    Adsorption and Fenton oxidation of azo dyes by magnetite nanoparticles deposited on a glass substrate
    (Elsevier, 2019) Unal, Bahar Ozbey; Bilici, Zeynep; Ugur, Naz; Isik, Zelal; Harputlu, Ersan; Dizge, Nadir; Ocakoglu, Kasim
    Fenton oxidation is an efficient and useful method for wastewater treatment. To increase overall reaction efficiencies and inhibit environmental impacts, developing advanced catalysts are crucial in this matter. The main goal of this study was to investigate the catalytic activity of the magnetite (Fe2+Fe23+O42-, FeFe2O4, or Fe3O4) nanoparticles (NPs) coated borosilicate glass on the color removal of basic red 18 (BR18) and acid red 8 (AR88) azo dyes by adsorption and Fenton oxidation reaction. The efficiency of powder magnetite NPs was also tested to compare to magnetite NPs coated borosilicate glass. The effect of solution pH (2.5-9.0), catalyst loading (0.25-3.0 g/L), and dye concentration (0.1-0.3 mM) were tested to achieve maximum color removal efficiency using powder magnetite NPs. The color removal efficiencies were measured 44% at pH 9.0 and 76% at pH 3.5 for adsorption and Fenton oxidation of BR18 dye (0.1 mM). Moreover, the color removal efficiencies were measured 81% at pH 3.5 and 100% at pH 6.0 for adsorption and Fenton oxidation of AR88 dye (0.1 mM). The effect of hydrogen peroxide (H2O2) concentration (2.5-25 mM) was also optimized and 10 mM was found optimum H2O2 dosage for Fenton oxidation. However, magnetite NPs coated borosilicate glass enhanced maximum 77% and 82% color removal efficiencies for adsorption and Fenton oxidation of BR18 dye. Maximum 86% and 100% color removal efficiencies were obtained for adsorption and Fenton oxidation of AR88 dye. Stability of the powder magnetite NPs and magnetite NPs coated borosilicate glass catalyst was also investigated. The reusability of the catalyst showed that magnetite NPs coated borosilicate glass could be used at least 3 times without significant loss of activity compared to powder magnetite NPs for Fenton oxidation. The characterization of the catalyst was carried out using scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDX), X-ray powder diffraction (XRD), and zeta potential analyses before and after adsorption.
  • [ X ]
    Öğe
    Investigation of in vitro biological activities of hollow mesoporous carbon nanoparticles bearing D-NMAPPD on human lung adenocarcinoma cells
    (Elsevier, 2022) Ugur, Naz; Harputlu, Ersan; Sezer, Canan Vejselova; Demirdogen, Ruken Esra; Ince, Mine; Unlu, C. Gokhan; Yurt, Fatma
    The uniformly dispersed hollow mesoporous carbon nanoparticles (HMCNPs) were successfully synthesized by hard-template methods, and D-NMAPPD (B13) was successfully loaded onto the nanoparticle surface for the first time. Structural properties of bare and B13 loaded HMCNPs (HMCNs-B-13) were investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Field Emission-Scanning Electron Microscopy (FE-SEM), Thermal Gravimetric Analysis (TG). The amount of drug released was determined via in vitro drug release studies at 37 degrees C in SBF through UV-Vis spectrometric and thermal analyses. TG data revealed that the proportion of loaded B-13 was 33.60%. Their ability to induce apoptosis in cultures of A549 human lung adenocarcinoma cells was investigated, and the inhibitory effect of HMCNPs-B-13 on lung cancer cell proliferation was determined in vitro. The IC50 values determined after application periods of 24 and 48 h were found to be 16.13 mu g/mL and 12.96 mu g/mL, respectively. The role of HMCNPs-B-13 on the morphology and ultrastructure of A549 cells was also investigated by confocal microscopy and Transmission electron microscopy (TEM) studies.
  • [ X ]
    Öğe
    Nano-cubes for energy storage
    (Elsevier Sci Ltd, 2020) Harputlu, Ersan; Gurgen, Seda; Ugur, Naz; Ocakoglu, Kasim
    [No abstract available]
  • [ X ]
    Öğe
    Photo-induced anti-inflammatory activities of chloro substituted subphthalocyanines on the mammalian macrophage in vitro
    (Elsevier Science Bv, 2019) Ayaz, Furkan; Ugur, Naz; Ocakoglu, Kasim; Ince, Mine
    In this study, a series of subphthalocyanines (SubPcs) derivatives were synthesized to generate unique immunomodulatory molecules that can be activated through photo-induction. Immunomodulatory agents have a great potential in medicine to manipulate the immune system according to our needs and prevent disease symptoms. Inflammation is one of these symptoms and macrophages play a crucial role in the generation of inflammatory responses. Being able to control the activity of these agents through photo-induction enables the fine tuning on their activities in a location specific and non-invasive manner with possibly minor side effects. Mammalian macrophages' pro-inflammatory activity was examined in the presence of our compounds as well as LPS as a danger mimic. These compounds exerted photo-induced anti-inflammatory activities on the macrophages. Number of Cl atoms was a defining factor in their photo-induced anti-inflammatory immunomodulatory efficiencies.
  • [ X ]
    Öğe
    Synthesis and characterization of composite catalysts comprised of ZnO/MoS2/rGO for photocatalytic decolorization of BR 18 dye
    (Elsevier, 2021) Ugur, Naz; Bilici, Zeynep; Ocakoglu, Kasim; Dizge, Nadir
    In recent years, photocatalysis upon semiconductor-based hybrid materials has received much attention for the improved environmental effects and energy applications. Many good semiconductors such as ZnO have large bandgaps and suffer from fast charge recombination which hinders photocatalytic activity. One possible strategy to overcome this problem is introducing a narrow bandgap co-catalyst. Within the context of this study, triple hybrid nanostructures comprised of ZnO nanorods and MoS2/rGO (MG) co-catalyst were synthesized and characterized by various analytical methods. Accordingly, 25ZnO/75MG and 75ZnO/25MG hybrid materials were synthesized for two different MG co-catalyst comprised of 0.5% (named as 25ZnO/75MG1) and 5% (named as 25ZnO/75MG2) graphene oxide. The photocatalytic activities of the heterostructures and pristine ZnO nanorods were evaluated by the degradation of BR 18 dye, a common water pollutant mainly from the textile industry. When introduced with the co-catalyst, 25ZnO/75MG1 heterostructures achieved 100% degradation for 180 min. Furthermore, when the GO amount in the co-catalyst was increased to 5%, fully degradation of the dye solution was realized by 25ZnO/75MG2 in the first 30 min. These results are indicative of a positive synergistic effect of MoS2-rGO co-catalyst. Also, it is shown that increasing the GO amount is an effective approach to accelerate charge separation and electron transport properties.
  • [ X ]
    Öğe
    Zn Phthalocyanine Derivatives for Solution-Processed Small Molecule Organic Solar Cells
    (Wiley-V C H Verlag Gmbh, 2018) Sari, Fatma Aslihan; Kazici, Mehmet; Harputlu, Ersan; Bozar, Sinem; Koyun, Ozge; Sahin, Yucel; Ugur, Naz
    Zinc phthalocyanine derivatives, 1 and 2, having either electron donating octyl-thiol group or electron accepting octyl-sulfonyl groups have been synthesized to serve as new electron donor components for bulk heterojunction (BHJ) solar cells. BHJ solar cells, in which the active layer consist of zinc phthalocyanine (ZnPc) as an electron donor and a soluble fullerene derivative, namely PCBM, as an electron acceptor component were produced and characterized. The device consisting of octylthiol-ZnPc:PCBM (1:4) gave power-conversion efficiencies of 0.42%. On the other hand, the device having octyl-sulfonyl substituted ZnPc gave very low efficiency due to both low Voc and Jsc values.