Yazarlar

  • MakaleYalnız künye2022Scopus SJRQ1
    Graphene-reinforced novel poly(acetoxystyrene-co-glycidylmethacrylate) composites: Synthesis and optimization of dielectric behaviors using response surface methodology

    Pihtili, Güzin

    In this work, a new copolymer synthesis of Poly(acetoxystyrene-co-glycidylmethacrylate) (P[AOS-co-GMA]) by free radical polymerization (FRP) method is reported. The polymer composites (P[AOS-co-GMA]/graphene), containing different amounts of graphene, were prepared by the solution casting technique. Composites of Poly(acetoxystyrene-co-glycidylmethacrylate) loaded with 2.03 mass%, 5.00 mass%, 7.97 mass%, and 10 mass% graphene. The structure of AOS-GMA systems was characterized by fourier transform infrared, 1H-NMR and scanning electron microscopy. Thermal features were evaluated by the thermogravimetric analysis and differential scanning calorimetry. The aim of this study is to optimize the ε′ (dielectric constant) and ε′′ (dielectric loss factor) of pure polymer and graphene-doped (2.03-5-7.97-10 mass%) P(AOS-co-GMA) composite using response surface methodology. For optimization of the process and creation of the mathematical model, the central composite design package was used. The significance of the process parameters in the model was evaluated by analysis of variance (ANOVA) research. The effects of process parameters, frequency (Hz), voltage (V), and graphene ratio (mass%) on ε′ and ε′′ were examined at ambient temperature. The maximum ε″ value (8.01) was reached at around the 699 Hz frequency and at 11.43 V voltage at the graphene content of 9.82 mass%. The model estimated the maximum value of the ε′′ (0.08) when the frequency was set at 51.20, the voltage was fixed at 1.16 and the graphene content was fixed at 9.97 wt%. The ANOVA results showed that frequency and graphene content were the main model parameters and had a remarkable effect on the dielectric properties. This article presents the development of a new polymeric composite and optimize effect of process parameters, such as frequency (A), voltage (B) and amount of graphene (C).

    AtıfScopus4WoS4OpenAlex4
    ScopusWeb of Scienceİncele
  • MakaleAçık Erişim2020Scopus SJRQ3
    Biosorptive removal of eriochrome black-T using agaricus campestris: Parameters optimization with response surface methodology

    Alp, Hevidar; Ince, Muharrem; Ince, Olcay Kaplan; Onal, Ali

    In this study, Eriochrome Black T (EBT) removal from aqueous media by Agaricus campestris (AC) which is an eco-friendly biosorbent was investigated using a central composite design (CCD) combined with response surface methodology. The CCD was chosen as the statistical prediction method to reduce the number of experiments which, in turn, will directly save time and chemicals. To opti-mize the process, various experimental independent variables such as the pH of the solution, contact time, adsorbent dosage and temperature were selected. The optimal experimental conditions were obtained as 6.5, 30°C, 20 min and 20 mg, for solution pH, temperature, contact time and adsorbent dosage, respectively. Under these optimized conditions, maximum EBT (100 mg L–1 initial concentra-tion) removal efficiency was calculated as 64.2 mg g–1. The independent variables and their interaction significance were checked using analysis of variance and it was found that the EBT biosorption on AC was highly significant (p < 0.001). The results were justified by the relatively high correlation coefficients (R2 = 0.9967) of the statistical prediction. The EBT biosorption was confirmed by fourier transform infrared spectroscopy (FTIR) analysis monitoring the functional groups during EBT biosorption on AC. This was the first report on the parameter optimization of EBT biosorp-tion using AC in an experimental design. The used biosorbent was characterized by FTIR, scanning electron microscope coupled with energy dispersive spectrometer and thermogravimetric analysis. The proposed biosorption process efficiently removed EBT, present in various aqueous mediums and can be used in industrial processes.

    AtıfScopus17WoS12
    ScopusWeb of Scienceİncele