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A combined DFT, Monte Carlo, and MD simulations of adsorption study of heavy metals on the carbon graphite (111) surface
(Elsevier, 2022) Khnifira, M.; Boumya, W.; Attarki, J.; Mahsoune, A.; Sadiq, M.; Abdennouri, M.; Kaya, S.
This work investigated the adsorption mechanism of heavy metals: silver (Ag), mercury (Hg), cadmium (Cd), palladium (Pd), and zinc (Zn) on the carbon graphite (111) surface based on density functional theory (DFT), Metropolis Monte Carlo (MMC), and the molecular dynamics (MD) simulation methods. The obtained results from the adsorption of these species showed that the process is spontaneous and exothermic in nature. The maximum adsorption capacities were obtained in neutral to low acid medium, and the interaction between Hgcarbon graphite was more favored than other systems. These findings showed that carbon graphite was more efficient in the removal of the studied metals. Moreover, this study better explains the adsorption mechanism of heavy metals onto carbon graphite and gives a theoretical basis for the wider application of graphite adsorbent in the removal of heavy metals. This paper provides theoretical support for heavy metals removal in various mediums and also provides some new ideas for the secondary utilization of quantum chemical descriptors and molecular dynamics simulation methods.
A detailed electronic-scale DFT modeling/MD simulation, electrochemical and surface morphological explorations of imidazolium-based ionic liquids as sustainable and non-toxic corrosion inhibitors for mild steel in 1 M HCl
(Elsevier, 2023) EL Hajjaji, F.; Ech-chihbi, E.; Salim, R.; Titi, A.; Messali, M.; El Ibrahimi, B.; Kaya, S.
Three new eco-friendly imidazolium-based ionic liquid derivatives with different chain lengths: [Eth-IM thorn , Br-], [Met-IM thorn , Br-] and [Prop-IM thorn , Br-] on mild steel in 1 M HCl was investigated. Electrochemical Impedance Spectroscopy, Potentiodynamic polarization techniques were used as experimental studies. Theoretical calcu-lations using DFT (Density Functional Theory) and molecular dynamics (MD) simulations were performed to demonstrate the reactivity behavior and the reactive sites of three molecules. The results revealed that these synthesized ionic liquids exhibited good corrosion inhibiting property >90 %. Electrochemical measurements showed that these organic compounds are mixed-type inhibitors. SEM and EDX examinations proved the for-mation of a protective layer of adsorbed inhibitors at the steel surface. The computational findings are in good agreement with inductive effects of methyl, Ethyl and Propyl functional groups.
Adsorption characteristics of dopamine by activated carbon: Experimental and theoretical approach
(Elsevier B.V., 2023) Khnifira, M.; Boumya, W.; Attarki, J.; Mahsoune, A.; Abdennouri, M.; Sadiq, M.; Kaya, S.
In this work, we investigate the adsorption mechanism of dopamine (DP) drug using an activated carbon (AC) type through experimental and theoretical data. Experiment series were carried out at different initial values of solution pH, temperature, reaction time and initial drug concentration. The effect of protonation and deprotonation of DP molecule was also investigated. The equilibrium isotherm data were evaluated using the Dubinin-Radushkevich, Langmuir, Temkin and Freundlich models. Elovich, pseudo-first and pseudo-second order kinetic models were used to analyze kinetic data. Here we also used molecular dynamic (MD) simulation and DFT-based computational methods to reach information about the electronic properties of DP drug and its adsorption mechanism that have not been experimentally observed. Experimental results show that the Elovich kinetic model and Langmuir model best describe the adsorption phenomenon. In parallel, the experimental analysis revealed that the adsorption process is spontaneous and endothermic. Dopamine adsorption on AC occurs quickly and is pH and temperature-dependent. Frontier molecular orbital (FMO) energies for neutral, deprotonated and protonated forms of DP were determined and thoroughly explained. The basic medium significantly impacts DP drug adsorption behavior, which has the greatest adsorption energy when the pH is less than 12. It was found that DP adsorption occurs in a bidentate geometry by forming strong bonds between molecular oxygens and carbon atoms on the AC surface. Based on theoretical calculations interaction mechanisms of DP on the AC (001) surface were proposed. © 2023 Elsevier B.V.
Adsorption mechanisms investigation of methylene blue on the (001) zeolite 4A surface in aqueous medium by computational approach and molecular dynamics
(Elsevier, 2022) Khnifira, M.; El Hamidi, S.; Sadiq, M.; Simsek, S.; Kaya, S.; Barka, N.; Abdennouri, M.
The cationic methylene blue (CMB) and its pmtonated forms have been studied by computational tools to predict their adsorption behavior on zeolite 4A. The interaction nature has been exhaustively studied in terms of energy gap (Delta E-g), global reactivity descriptors, Fukui functions, adsorption energy, density of states and natural bond orbital analysis. It was found that the protonated CMB (N36N35) molecule is less stable, more electmphilic and very reactive. The highest contribution to the lowering of the stabilization energy (E-2) for all systems was mainly due to the intramolecular charge transfer from the lone pair of the nitrogen atoms as a donor orbital to pi* as an acceptor orbital. DFT calculations revealed that N36 and N35 site of CMB was faced with a lower energy gap (Delta E-g) and chemical hardness (eta) as well as a higher electron accepting power compared to other sites. Monte Carlo molecular modeling simulation (MCMM) confirmed the predominant of electrostatic interactions and p-p electron coupling. The studied compounds prefer to have configurations that facilitate p-p interaction, which is evident from the parallel orientation of CMB with zeolite surface. The dynamic parameters show that the adsorption of methylene blue is exothermic and spontaneous chemisorption.
Adsorption of methylene blue cationic dye onto brookite and rutile phases of titanium dioxide: Quantum chemical and molecular dynamic simulation studies
(Elsevier, 2021) Khnifira, M.; El Hamidi, S.; Mahsoune, A.; Sadiq, M.; Serdaroglu, G.; Kaya, S.; Qourzal, S.
This study reports the statistical physics modeling of the methylene blue cationic dye (MBCD) adsorption in aqueous solution on TiO2 surface. In order to comprehend the adsorption performance, theoretical investigations were done to collect extensive information about the chemical and physical properties of the molecules using quantum chemical parameters (QCP). Also, molecular dynamic and quantum descriptors were applied to better understand the dye adsorption on different phases of TiO2 (i.e., bmokite and rutile). The molecular structures of MBCD acts as good electron donators to an empty d orbital of TiO2 due to the availability of electrons in both the lone pair on the N atoms and 't electrons of the aromatic rings. The reactivity of optimized molecular structures was confirmed by the quantum chemical descriptors. Modeling results showed that the adsorption was performed with a horizontal position of MBCD molecules on both surfaces. Overall, the TiO2 showed the highest adsorption energies for protonated MBCD (N36N35) (-886.533 kcal/mol (MBCD/rutile-TiO2)) > -626.428 kcal/mol (MBCD/brookite-TiO2)), which implies that these sites prompt the adsorption on both surfaces. The analysis of the adsorption energy values showed an exothermic chemisorption process, which could be governed by steric parameters according to the results obtained with the molecular dynamics modeling.
Alpha-linoleic acid (ALA) as a corrosion inhibitor for XC48 steel in H2SO4 medium: an experimental and computational study
(Vserossiiskaya Assotsiatsiya Korrozionistov, 2022) Merimi, C.; Zaidi, K.; Hammouti, B.; Guo, L.; Kaya, S.; Elmsellem, H.; Aouniti, A.
Iron and steel materials are extensively used in many industries due to low cost and availability. We suggested alpha-linolenic acid (ALA) to slow down the corrosion of XC48 steel in H2SO4 solution. We chose ALA because it comprises a carboxylic group and an aliphatic chain containing 17 carbons with three double bonds. This work was conducted by electrochemical measurements (stationary current-voltage curves) and gravimetric measurements (weight loss method) at various temperatures (298-348 K). The findings show that this agent acts as a strong inhibitor in a large concentration range. The inhibition effect is 92% at a concentration of 5 center dot 10-3 M. Adsorption and activation parameters were also evaluated. Conceptual Density Functional Theory calculations and the results of the Molecular Dynamic Simulation Approach are in good agreement with the experimental observations.
Anti-corrosion Properties of 2-Phenyl-4(3H)-quinazolinone-Substituted Compounds: Electrochemical, Quantum Chemical, Monte Carlo, and Molecular Dynamic Simulation Investigation
(Springer, 2020) Kacimi, Y. El; Touir, R.; Alaoui, K.; Kaya, S.; Abousalem, A. Salem; Ouakki, M.; Touhami, M. Ebn
In this investigation, attempts have been made to study the corrosion inhibition properties of three new 2-phenyl-4(3H)-quinazolinone-substituted compounds for mild steel in 1.0 M hydrochloric acid medium. The evaluation was carried out using mass loss, electrochemical impedance spectroscopy, and polarization curves measurement. It is shown that 2-phenyl-4(3H)-quinazolinone-substituted compounds are very good inhibitor’s for mild steel corrosion in 1.0 M hydrochloric acid medium, which acts as mixed-type inhibitors. So, the inhibition efficiency was increased with inhibitor concentration in the order Q-p-Cl > Q-m-Cl > Q-H, which depends on their molecular structures and the chloride para/metapositions. Electrochemical impedance spectroscopy has shown that all compounds act by the formation of a protective film at the metal surface. The correspondence between inhibition property and molecular structure of the 2-phenyl-4(3H)-quinazolinone-substituted compounds is investigated, using density functional theory (DFT). The effect of molecular structure on the inhibition efficiency has been explored by quantum chemical computations and obvious correlations were observed. The binding energies of tested compounds on Fe(110) surfaces were calculated using molecular dynamics simulation. Experimental and DFT study was further supported by molecular dynamic (MD) simulations study. © 2020, Springer Nature Switzerland AG.
Comparison of traditional and fullerene-based adsorbents for extraction of 1,4-dioxane and 2-methyl-1,3-dioxolane from milk
(Russian Acad Sciences, Inst Metals Superplasticity Problems, 2021) Kochaev, A., I; Razavi, R.; Kaya, S.; Mogaddam, M. R. A.; Altunay, N.; Nemati, M.; Katin, K. P.
Using density functional methods, the results of the analysis of traditional adsorbents and adsorbents based on nanosized particles capable of trapping 1,4-dioxane and 2-methyl-1,3-dioxolane molecules in milk are presented. We considered the following interacting compounds: 1,4-dioxane - primary amine, 1,4-dioxane - secondary amine, 1,4-dioxane - fullerene C-20, 1,4-dioxane-a fragment of the structure of activated carbon, 2-methyl-1,3-dioxolane - primary amine, 2-methyl-1,3-dioxolane-secondary amine, 2-methyl-1,3-dioxolane - fullerene C-20, 2-methyl-1,3-dioxolane - a fragment of the structure of activated carbon. We determined the optimal configurations of the corresponding interacting structures, estimated their binding energies and chemical potentials. The highest binding energy was obtained for 1,4-dioxane adsorbed on C-20 fullerene. At the same time, the energy gaps between the occupied HOMO and unoccupied LUMO molecular states were calculated, which makes it possible to characterize the reactivity and stability of molecules. Compounds of 1,4-dioxane and 2-methyl-1,3-dioxolane with amines have rather large gaps HOMO-LUMO. Using the concept of the electronic localization function, we found that a covalent bond is formed between 1,4-dioxane and C-20 fullerene with a sufficiently high degree of electron localization in the bond region. In other cases, the value of the localization function indicates the absence of a chemical bond between the compounds. The proposed study gives recommendations on the adsorption of 1,4-dioxane and 2-methyl-1,3-dioxolane for further solid-phase microextraction, which will allow them to be found in milk by gas chromatography using a flame ionization detector.
A complete computational and spectroscopic study of 2-bromo-1, 4-dichlorobenzene - A frequently used benzene derivative
(ELSEVIER SCIENCE BV, 2018) Vennila, P.; Govindaraju, M.; Venkatesh, G.; Kamal, C.; Mary, Y. Sheena; Panicker, C. Yohannan; Kaya, S.; Armakovic, Stevan; Armakovic, Sanja J.
The coupled experimental and theoretical vibrational investigation of 2-bromo-1, 4-dichlorobenzene (BDB) molecule has been carried out and they have been duly compared with standard values in order to produce the reliability of the results. Results of DFT analysis carried out using B3LYP functional with 6-31 + G/6-311++G (d,p) basis set revealed that BDB has higher electronic density. The molecular geometry,C-13 & H-1 Nuclear Magnetic Resonance (NMR), Natural Bond Orbital (NBO) and Natural Atomic Charge analyses have been obtained by OFT calculations. Nonlinear optical (NLO) properties, quantum chemical descriptors and first order hyperpolarizability have been calculated. In addition, Local reactivity properties reflected through average local ionization energies (ALIE), Fukui functions and bond dissociation energies have also been investigated. Besides investigation of docking properties, molecular dynamics simulations were also taken in account with a view to identify atoms that have relatively important interactions with water molecules. The title compound forms a stable complex with isopentenylpyrophosphate transferase with a binding affinity value as -4.6 kCal./Mol. and shows inhibitory activity against isopentenylpyrophosphate transferase. (C) 2017 Published by Elsevier B.V.
Concomitant syphilis infection in patients with diagnosed HIV/AIDS: a retrospective multicentre study
(JOHN WILEY & SONS LTD, 2018) Sarigul, F.; Sayan, M.; Inan, D.; Deveci, A.; Ceran, N.; Celen, M.; Cagatay, A.; Ozdemir, H. Ozkan; Kuscu, F.; Karagoz, G.; Heper, Y.; Karabay, O.; Dokuzoguz, B.; Kaya, S.; Erben, N.; Karaoglan, I.; Ersoz, G. Munis; Gunal, O.; Hatipoglu, C.; Kutlu, S. Sayin; Akbulut, A.; Saba, R.; Sener, A.; Buyuktuna, S.
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Corrosion inhibition studies for mild steel in 5.0 M HCl by substituted phenyltetrazole
(SPRINGER HEIDELBERG, 2017) El Kacimi, Y.; Azaroual, M. A.; Touir, R.; Galai, M.; Alaoui, K.; Sfaira, M.; Touhami, M. Ebn; Kaya, S.
The inhibition efficiency of three substituted phenyltetrazole compounds, namely 5-(4-chlorophenyl)-1H-tetrazole (Cl-PT), 5-(4-methoxyphenyl)-1H-tetrazole (MO-PT), and 5-phenyl-1H-tetrazole (PT), for mild steel corrosion in 5.0 M HCl solution was investigated using weight loss measurements and electrochemical study. It is showed that these compounds are good inhibitors for mild steel corrosion in 5.0 M HCl solution which act as cathodic type inhibitors. So, the inhibition efficiency was increased with inhibitor concentration in the order of Cl-PT > MO-PT > PT which depended on their molecular structures. It is found also that these compounds toke its performance at different temperatures range from 298 to 328 K. In addition, the thermodynamic adsorption parameters at different concentrations were investigated and discussed. Finally, it is seen that the inhibition efficiency of the studied compounds increased with immersion time to reach a maximum at 12 h.
Discovery of novel pyrrolo[2,3-d]pyrimidine derivatives as anticancer agents: virtual screening and molecular dynamic studies
(Taylor & Francis Ltd, 2024) Dhiman, S.; Gupta, S.; Kashaw, S. K.; Chtita, S.; Kaya, S.; Almehizia, A. A.; Asati, V.
CDK/Cyclins are dysregulated in several human cancers. Recent studies showed inhibition of CDK4/6 was responsible for controlling cell cycle progression and cancer cell growth. In the present study, atom-based and field-based 3D-QSAR, virtual screening, molecular docking and molecular dynamics studies were done for the development of novel pyrrolo[2,3-d]pyrimidine (P2P) derivatives as anticancer agents. The developed models showed good Q2 and r2 values for atom-based 3D-QSAR, which were equal to 0.7327 and 0.8939, whereas for field-based 3D-QSAR the values were 0.8552 and 0.6255, respectively. Molecular docking study showed good-binding interactions with amino acid residues such as VAL-101, HIE-100, ASP-104, ILE-19, LYS-147 and GLU-99, important for CDK4/6 inhibitory activity by using PDB ID: 5L2S. Pharmacophore hypothesis (HHHRR_1) was used in the screening of ZINC database. The top scored ZINC compound ZINC91325512 showed binding interactions with amino acid residues VAL-101, ILE-19, and LYS-147. Enumeration study revealed that the screened compound R1 showed binding interactions with VAL 101 and GLN 149 residues. Furthermore, the Molecular dynamic study showed compound R1, ZINC91325512 and ZINC04000264 having RMSD values of 1.649, 1.733 and 1.610 & Aring;, respectively. These ZINC and enumerated compounds may be used for the development of novel pyrrolo[2,3-d]pyrimidine derivatives as anticancer agent.
Evaluation of inhibitive and adsorption behavior of thiazole-4-carboxylates on mild steel corrosion in HCl
(Elsevier, 2020) El aoufir, Y.; Zehra, S.; Lgaz, H.; Chaouiki, A.; Serrar, H.; Kaya, S.; Salghi, R.
The present work describes the corrosion inhibiting properties of three synthesized thiazole-4-carboxylates namely, methyl (E)-5-(4-chlorophenyl)-2-(((E)-4-methylbenzylidene)hydrazono)-2,3-dihydrothiazole-4-carboxylate (T1), methyl (E)-5-(4-chlorophenyl)-2-(((E)-4-nitrobenzylidene)hydrazono)-2,3-dihydrothiazole-4-carboxylate (T2) and methyl (E)-2-(((E)-4-chlorobenzylidene)hydrazono)-5-(4-chlorophenyl)-2,3-dihydrothiazole-4-carboxylate (T3) towards corrosion of mild steel (MS) in 1.0 mol/L HCl. Various techniques like electrochemical measurements, SEM-EDX analysis, Density Functional Theory (DFT) and molecular dynamics (MD) simulations were employed to probe the effects of substituent groups on inhibition performances of investigated compounds. EIS studies indicated the adsorbed protective film's construction on the steel/electrolyte interface by tested molecules; its existence was affirmed by SEM-EDX analysis. Polarization studies revealed a mixed-type of corrosion inhibition activity. Their mode of adsorption was studied by using isotherm models, and the best match was found just in case of Langmuir adsorption isotherm. Electrochemical results showed that the polarization resistance was greatly increased, from an initial value for the MS (in 1.0 mol/L HCl) of 20.24 up to 256.7 Omega cm(2) for the inhibited solution (1.0 mol/L HCl with 5 x 10(-4) mol/L of T3). Tested compounds behaved as effective inhibitors for MS corrosion in HCl at all concentrations with better efficacy at an optimal concentration of 5 x 10(-4) mol/L. Among all the tested inhibitors, T3 exhibited the most effective performance with an inhibition of 92 %, and the order of the inhibition potency is found within the order of T3 > T2 > T1 by all utilized techniques. The morphological examinations of the surface of MS specimens were explored by using SEM/EDX analysis. DFT calculations were not in agreement with experimental results while MD simulations confirmed the dependence of inhibition performances on the molecular structure of tested compounds.
Evaluation of tularaemia courses: a multicentre study from Turkey
(ELSEVIER SCI LTD, 2014) Erdem, H.; Ozturk-Engin, D.; Yesilyurt, M.; Karabay, O.; Elaldi, N.; Celebi, G.; Korkmaz, N.; Guven, T.; Sumer, S.; Tulek, N.; Ural, O.; Yilmaz, G.; Erdinc, S.; Nayman-Alpat, S.; Sehmen, E.; Kader, C.; Sari, N.; Engin, A.; Cicek-Senturk, G.; Ertem-Tuncer, G.; Gulen, G.; Duygu, F.; Ogutlu, A.; Ayaslioglu, E.; Karadenizli, A.; Meric, M.; Ulug, M.; Ataman-Hatipoglu, C.; Sirmatel, F.; Cesur, S.; Comoglu, S.; Kadanali, A.; Karakas, A.; Asan, A.; Gonen, I.; Kurtoglu-Gul, Y.; Altin, N.; Ozkanli, S.; Yilmaz-Karadag, F.; Cabalak, M.; Gencer, S.; Pekok, A. Umut; Yildirim, D.; Seyman, D.; Teker, B.; Yilmaz, H.; Yasar, K.; Balkan, I. Inanc; Turan, H.; Uguz, M.; Kilic, S.; Akkoyunlu, Y.; Kaya, S.; Erdem, A.; Inan, A.; Cag, Y.; Bolukcu, S.; Ulu-Kilic, A.; Ozgunes, N.; Gorenek, L.; Batirel, A.; Agalar, C.
In this multicentre study, which is the largest case series ever reported, we aimed to describe the features of tularaemia to provide detailed information. We retrospectively included 1034 patients from 41 medical centres. Before the definite diagnosis of tularaemia, tonsillitis (n=653, 63%) and/or pharyngitis (n=146, 14%) were the most frequent preliminary diagnoses. The most frequent clinical presentations were oropharyngeal (n=832, 85.3%), glandular (n=136, 13.1%) and oculoglandular (n=105, 10.1%) forms. In 987 patients (95.5%), the lymph nodes were reported to be enlarged, most frequently at the cervical chain jugular (n=599, 58%), submandibular (n=401, 39%), and periauricular (n=55, 5%). Ultrasound imaging showed hyperechoic and hypoechoic patterns (59% and 25%, respectively). Granulomatous inflammation was the most frequent histological finding (56%). The patients were previously given antibiotics for 1176 episodes, mostly with -lactam/-lactamase inhibitors (n=793, 76%). Antituberculosis medications were provided in seven (2%) cases. The patients were given rational antibiotics for tularaemia after the start of symptoms, with a mean of 26.8 +/- 37.5days. Treatment failure was considered to have occurred in 495 patients (48%). The most frequent reasons for failure were the production of suppuration in the lymph nodes after the start of treatment (n=426, 86.1%), the formation of new lymphadenomegalies under treatment (n=146, 29.5%), and persisting complaints despite 2weeks of treatment (n=77, 15.6%). Fine-needle aspiration was performed in 521 patients (50%) as the most frequent drainage method. In conclusion, tularaemia is a long-lasting but curable disease in this part of the world. However, the treatment strategy still needs optimization.
Experimental and theoretical analysis of molecular structure, vibrational spectra and biological properties of the new Co(II), Ni(II) and Cu(II) Schiff base metal complexes
(Elsevier, 2021) Sakthivel, R. V.; Sankudevan, P.; Vennila, P.; Venkatesh, G.; Kaya, S.; Serdaroglu, G.
A new novel Cobalt, Nickel and Copper metal complexes were synthesized from Schiff base ligand of 2,2'-((1E,1'E)-(( 4-nitro-1,2-phenylene) bis(azanylylidene)) bis(methanylylidene)) diphenol. The structures of all the synthesised compounds have been analysed using Fourier-Transform Infrared (FT-IR), Nuclear Magnetic Resonance (NMR) spectroscopy, Ultraviolet-Visible (UV-Vis) spectrum, elemental analysis and Powder X-ray diffraction (PXRD). The experimental spectral frequencies of ligand and metal complexes are correlated with theoretically computed vibrational frequencies. The molecular structure of the ligand and its metal complexes has been optimized using B3LYP-6-311G(d,p)/LANL2DZ basis set and their parameters have been discussed. Natural bond orbital and Frontier Molecular Orbital analysis have assessed the presence of a metal-ligand bond in complexes. Further, biological activity studies such as antioxidant, anti-inflammatory, antidiabetic have also been analyzed using various methods. In addition, molecular docking studies have also been performed on all complexes using the oz-amylase enzyme structure to calculate the possible binding energy of inhibitors. (C) 2021 Published by Elsevier B.V.
Experimental and theoretical approach for novel imidazolium ionic liquids as Smart Corrosion inhibitors for mild steel in 1.0 M hydrochloric acid
(Elsevier, 2022) Nahle, A.; Salim, R.; EL Hajjaji, F.; Ech-chihbi, E.; Titi, A.; Messali, M.; Kaya, S.
3-(4-hydroxybutyl)-1-phenethyl-1H-imidazol-3-ium chloride ([HB-Imid] Cl), and 3-(2-c hlorobenzyl)-1-phenethyl-1H-imidazol-3-ium chloride ([CB-Imid] Cl) were investigated as corrosion inhibitors for mild steel in 1.0 M hydrochloric acid solution. Electrochemical techniques (PDP and EIS) were performed as experimental studies while DFT at B3LYP 6-311G (df,pd), and molecular dynamic simulation were used as theoretical approach. PDP experiments revealed that the studied ionic liquids (ILs) behaved as mixture type inhibitors. EIS results indicated that these compounds showed good inhibition performance with inhibition efficiency around 95% at the optimum concentration of 1.0 x 10-3 M. According to Langmuir isotherm model and the thermodynamic parameters, these ILs were adsorbed onto the mild steel surface through physical and chemical bonds. SEM and EDX examinations proved the formation of a protective layer of adsorbed inhibitors at the steel surface. The DFT/B3LYP/6-311G(df,pd) computations in both the gas and water environments disclosed that [HB-Imid] Cl molecule was softer and had a lower energy gap, electrodonating power, and polarizability indexes.(c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Experimental and theoretical explorations of S-alkylated mercaptobenzimidazole derivatives for use as corrosion inhibitors for carbon steel in HCl
(Elsevier, 2021) Damej, M.; Benmessaoud, M.; Zehra, S.; Kaya, S.; Lgaz, Hassane; Molhi, A.; Labjar, N.
Two mercaptobenzimidazole derivatives, namely the 1H-benzimidazol-2-thioyl hexane (MBI-C-6) and the 1H-benzimidazol-2-thioyl dodecane (MBI-C-12) were synthesized. The corrosion inhibiting potential of both compounds was studied in HCl solution (1.0 M HCl) for carbon steel. The investigation was conducted using gravimetric, electrochemical, Density Functional Theory (DFT), and molecular dynamics (MD) assessment methods. The carbon steel surfaces with or without the MBI-C-6 and MBI-C-12 were also assessed employing a Scanning Electron Microscope (SEM). The findings showed a high inhibition efficiency for both MBI-C-6 and MBI-C-12 at low concentrations, reaching 90% and 95.7% for MBI-C6 and MBI-C-12 at 10(-3) mol/L, respectively. Impedance results showed that the polarization resistance was greatly increased, from an initial value for the CS (in blank) of 12 up to 241 Omega cm(2) for the inhibited solution (1.0 mol/L HCl with 10(-3) mol/L of MBI-C-12). Tested compounds inhibited CS corrosion through a physical-chemical adsorption mechanism that followed Langmuir adsorption isotherm model with a change in the free energy of adsorption from -35.97 to -38.63 kJ/mol. DFT calculations and MD simulations were used to check the effect of the molecular structure of MBI-C-6 and MBI-C-12 on their reactivity and, on the other hand, to explain their adsorption mode on themetal surface. By scanning electron microscopy (SEM), the adequate protection of carbon steel by the usage of MBI-C-6 and MBI-C-12 in 1.0 M HCl was confirmed. All the outcomes from experimental findings and theoretical calculations were in line. (C) 2021 Elsevier B.V. All rights reserved.
Experimental and theoretical insights on the structural and optical properties of GeOx thin films deposited via RF magnetron sputtering under varying oxygen percentage
(ELSEVIER, 2023) Şenadım Tüzemen, E.; Hopoğlu, H.; Sarıtaş, S.; Aydınoğlu, H.S.; Ertuğrul, M.; Maslov, M.M.; Kaya, S.; Ungan F; Gür, E.
In this study, GeOx films were produced by radio frequency magnetron sputtering (RFMS) under varying oxygen percentages. The structural and optical properties of films grown have been studied experimentally and theoretical calculations have been presented using density functional theory (DFT). Considering the x-ray diffraction (XRD) analysis, Ge (111) peak was observed in the as-deposited film produced only at 2% oxygen percentage. In order to emerge crystal phases, all the amorphous films were annealed at 900 ◦C under atmospheric conditions. It was found that the intensity of the (101) peak increased as the oxygen percentage increased. At the same time, film grown at 2% oxygen percentage was annealed at different annealing temperatures sequentially at 850, 900, and 950 ◦C. As a result, the polycrystalline properties changed as the annealing temperature increased. It was found that the optical properties of the films grown are strongly dependent on the oxygen percentage. As the oxygen percentage has changed, the energy band gap has increased to the values 2.30, 2.31, 2.58, and 6.28 eV. There are Ge-O-Ge antisymmetric stretching peaks appeared at 861.51 cm 1, 949.94 cm 1 and symmetric stretching of hexagonal peaks at 516.34 cm 1, 546.29 cm 1, 581.95 cm 1. The energy band gap results of the density functional theory (DFT) calculations are in good agreement with the experimental observations.
Experimental and theoretical studies for mild steel corrosion inhibition in 1.0 M HCl by three new quinoxalinone derivatives
(ELSEVIER SCIENCE BV, 2016) Tazouti, A.; Galai, M.; Touir, R.; Touhami, M. Ebn; Zarrouk, A.; Ramli, Y.; Saracoglu, M.; Kaya, S.; Kandemirli, F.; Kaya, C.
Three quinoxalinone derivatives, namely (E)-3-styrylquinoxalin-2(1H)-one (SQ), (E)-3-(4methoxystyryl)quinoxalin-2(1H)-one (MOSQ) and (E)-3-(4-methoxystyry1)-7-methylquinoxalin-2(1H)-one (MOSMQ) were synthesized and characterized. Thus, their inhibition effects on mild steel corrosion in 1.0 M HCl medium were investigated using weight loss method, electrochemical measurements. The effect of temperature on the corrosion behavior of mild steel was studied in the range of 298-328 K. Polarization measurements indicated that, the studied compounds act as a mixed type inhibitors, the inhibition efficiency depends on their concentrations and followed the order MOSQ> MOSMQ> SQ Electrochemical impedance spectroscopy showed that all compounds act by the formation of a protective film at the metallic surface. The adsorption of three inhibitors on steel surface obeyed Langmuir model, thus the thermodynamic and kinetic parameters were calculated and discussed. In the part based on DFF calculations of this study, some electronic properties of studied molecules were calculated and discussed with the help of B3LYP/6-311G (d,p), B3LYP/6-311 ++G (d,p) and B3LYP/6-311G ++ (2d,2p) methods. The theoretical and experimental results are in good agreement. (C) 2016 Elsevier B.V. All rights.reserved.
The features of infectious diseases departments and anti-infective practices in France and Turkey: a cross-sectional study
(SPRINGER, 2014) Erdem, H.; Stahl, J. P.; Inan, A.; Kilic, S.; Akova, M.; Rioux, C.; Pierre, I.; Canestri, A.; Haustraete, E.; Engin, D. O.; Parlak, E.; Argemi, X.; Bruley, D.; Alp, E.; Greffe, S.; Hosoglu, S.; Patrat-Delon, S.; Heper, Y.; Tasbakan, M.; Corbin, V.; Hopoglu, M.; Balkan, I. I.; Mutlu, B.; Demonchy, E.; Yilmaz, H.; Fourcade, C.; Toko-Tchuindzie, L.; Kaya, S.; Engin, A.; Yalci, A.; Bernigaud, C.; Vahaboglu, H.; Curlier, E.; Akduman, D.; Barrelet, A.; Oncu, S.; Korten, V.; Usluer, G.; Turgut, H.; Sener, A.; Evirgen, O.; Elaldi, N.; Gorenek, L.
The aim of this study was to assess the infectious diseases (ID) wards of tertiary hospitals in France and Turkey for technical capacity, infection control, characteristics of patients, infections, infecting organisms, and therapeutic approaches. This cross-sectional study was carried out on a single day on one of the weekdays of June 17-21, 2013. Overall, 36 ID departments from Turkey (n = 21) and France (n = 15) were involved. On the study day, 273 patients were hospitalized in Turkish and 324 patients were followed in French ID departments. The numbers of patients and beds in the hospitals, and presence of an intensive care unit (ICU) room in the ID ward was not different in both France and Turkey. Bed occupancy in the ID ward, single rooms, and negative pressure rooms were significantly higher in France. The presence of a laboratory inside the ID ward was more common in Turkish ID wards. The configuration of infection control committees, and their qualifications and surveillance types were quite similar in both countries. Although differences existed based on epidemiology, the distribution of infections were uniform on both sides. In Turkey, anti-Gram-positive agents, carbapenems, and tigecycline, and in France, cephalosporins, penicillins, aminoglycosides, and metronidazole were more frequently preferred. Enteric Gram-negatives and hepatitis B and C were more frequent in Turkey, while human immunodeficiency virus (HIV) and streptococci were more common in France (p < 0.05 for all significances). Various differences and similarities existed in France and Turkey in the ID wards. However, the current scene is that ID are managed with high standards in both countries.

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