Yazar "Gece, Gökhan" seçeneğine göre listele

Listeleniyor 1 - 5 / 5
  • Küçük Resim Yok
    Öğe
    A DFT STUDY OF N-ACETYLCYSTEINE AND D-PENICILLAMINE AS CORROSION INHIBITORS FOR COPPER
    (Ankara Üniversitesi, 2025) Gece, Gökhan; Bilgiç, Semra
    The most popular and accessible corrosion inhibitors, i.e., silicates, chromates, phosphates, nitrites, amines, and numerous formulations based on these compounds, are toxic and fail to produce a universal effect. Amino acids and their derivatives are non-toxic, relatively cheap, biodegradable compounds. These molecules can form a barrier through adsorption on the copper surface to reduce the corrosion, and it has been observed that the adsorption depends mainly on the coordination of bidentate ligands, which occurs through an amino or carboxyl group and thiol group -SH. In recent years, there has been considerable progress in the description of the structure and inhibition properties of corrosion inhibitors by using quantum chemical calculations. In this study, the molecular and electronic structures of N-acetylcysteine and D-penicillamine have been justified by comparing the theoretical data from the density functional theory (DFT) method with experimental corrosion inhibition efficiencies. The theoretical results were found to be consistent with the reported experimental data.
  • Küçük Resim Yok
    Öğe
    Anti-corrosion characteristics of ampicillin and flucloxacillin drugs: A theoretical study
    (Ankara Üniversitesi, 2023) Gece, Gökhan; Bilgiç, Semra
    To determine the inhibition efficiency of a corrosion inhibitor, multiple experimental measurements need to be carried out, which is a time-consuming and resource-intensive task. On the other hand, quantum chemical methods are useful research tools for corrosion scientists. In this study, the corrosion inhibition effects of ampicillin and flucloxacillin at the molecular level were evaluated considering some descriptors by density functional theory (DFT) at B3LYP/6-311++G(d,p) level.
  • Küçük Resim Yok
    Öğe
    Metal oxidation prevention of low carbon steel in acidic medium: synthesis, electrochemical, and theoretical studies of a novel di-cationic pyridinium surfactant
    (Russian Association of Corrosion Engineers, 2025) Gece, Gökhan; Öztürk, Serkan; Akgül, Gülşen
    Low carbon steels are widely used industrially, especially in the automotive and construction sectors. The corrosion rates of these metals in acidic environments are generally very fast and it is of particular importance to prevent metal corrosion in this environment. For this reason, in this study, di-cationic surfactant containing two pyridinium nitrogen with corrosion inhibitory potential, named 1-dodecyl-2-(11-(pyridin-1-ium-1-yl)undecanamido)pyridin-1-ium di-bromide (DPUP), was synthesized. The structure of this compound was elucidated by spectroscopic methods (FT-IR and NMR) and electrochemical measurement methods (potentiodynamic polarization and electrochemical impedance spectroscopy) were preferred to determine the corrosion inhibition activities at different concentrations (2, 10 and 50 ppm) at room temperature (25°C). The lowest corrosion rate and the highest corrosion inhibition efficiency were obtained at an inhibitor concentration of 50 ppm. In order to understand whether this new compound was adsorbed on the metal surface, and thereby making the surface hydrophobic, contact angle measurement was performed using the drop method. Adsorption isotherm studies were performed to determine the predominant type of adsorption (physical or chemical) of the compound adsorbed on the steel surface and it was found to be in accordance with Langmuir. In addition, SEM + EDX analysis was performed on the metal surfaces to visually support that the metal is protected against corrosion and theoretical calculations were carried out using Density Functional Theory (DFT) method. © 2025, Russian Association of Corrosion Engineers. All rights reserved.
  • Küçük Resim Yok
    Öğe
    PROBING THE STRUCTURE-CORROSION INHIBITION PROPERTY RELATIONSHIP OF PYRROLE OLIGOMERS WITH DFT CALCULATIONS
    (Ankara Üniversitesi, 2019) Gece, Gökhan; Bilgiç, Semra
    Density functional theory (DFT) calculations on pyrrole oligomers were carried out at the B3LYP/6-311+G(d,p) level to search the relationship between the molecular structure and corrosion inhibition. The electronic properties such as the highest occupied molecular orbital (HOMO), the lowest unoccupied molecular orbital (LUMO) energy levels, energy gap (LUMO-HOMO) and dipole moment were computed. It was found that these electronic values can explain some features of the inhibition phenomena.
  • Küçük Resim Yok
    Öğe
    Synthesis, characterization, and studies of the interfacial and anticorrosion properties of a ternary cationic ionic liquid on carbon steel in a molar concentration of hydrochloric acid: Experimental and computational insights
    (Elsevier B.V., 2024) Öztürk, Serkan; Gerengi, Hüsnü; Solomon, Moses M.; Gece, Gökhan; Yıldırım, Ayhan; Olasunkanmi, Lukman O.
    Corrosion in acidic environments is a serious industrial challenge that must be addressed and cationic ionic liquid play a critical role in tackling the wet corrosion menace for the metal industry. For this purpose, a novel ternary cationic ionic liquid namely N1-(3-(11-(octadecyldimethylammonio)undecanamido)propyl)-N1,N1,N2,N2,N2-pentamethylethane-1,2-diaminium tribromide (Mono-18–11-di-N) is synthesized and elucidated for anticorrosion activity on St37–2 grade steel in a molar concentration of hydrochloric acid medium. The structural elucidation of Mono-18–11-di-N was achieved by FT-IR, 1H NMR, and 13C NMR methods while the electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), dynamic-EIS, density functional theory (DFT) calculations, and Monte Carlo (MC) simulation techniques were adopted in the anticorrosion evaluation. The Critical Micelle Concentration (CMC) of Mono-18–11-di-N is 0.000491 M and at CMC, the surface tension is 21.86 dyn cm?1 inferring good surface activity properties. Mono-18–11-di-N is effective against the wet corrosion of St37–2 steel. It can, at 20 mg/L decrease the corrosion rate of the metal from 0.57 mm/y to 0.11 mm/y and enhance the polarization resistance from 363 ? cm2 to 1908 ? cm2. A corrosion rate of 0.03 mm/y and an inhibition efficiency of 93% is achievable after 24 h of immersion at 25 °C. Additionally, surface morphological examination using scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), optical profilometer (OP), and atomic force microscope (AFM) methods prove the adsorption of Mono-18–11-di-N molecules on the substrate surface. Moreover, DFT and MC simulations revealed that Mono-18–11-di-N relies on lone pairs of electrons in bromide anion, oxygen, and nitrogen atoms to adsorb parallel to the St37–2 surface and protect it against corrosion. © 2023 Elsevier B.V.