Mehdi Shihab
@nahrainuniv.edu.iq
chemistry/sciene
Al-Nahrain University
RESEARCH INTERESTS
organic synthesis and applications
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
mehdi shihab and muna mahmood
Egypts Presidential Specialized Council for Education and Scientific Research
Mohammad Ahmed, Mehdi Shihab, and Conference Chemistry
Egypts Presidential Specialized Council for Education and Scientific Research
Zahraa T. Khudhair and Mehdi Salih Shihab
Allerton Press
Tahseen R. Ali, Taghried A. Salman, and Mahdi S. Shihab
AIP Publishing
Zainab Ali Al-Ta,ay, Shrok Allami, and Mehdi Salih Shihab
University of Baghdad College of Science
In this work proton exchange membranes were prepared by a modified microwave casting solution technique, using the polymers blend (polyethersulfone (PES), polystyrene (PS), polyvinylidenefluride (PVDF)). Modified casting method was used to overcome the poor compatibility between hydrophilic, (PES, PS) and hydrophobic PVDF, by cooling the substrate during the film casting process to (4.5-5.5oC). Membranes were chemically modified by three reaction types to study the differences between their effects on the required properties for microbial fuel cell application. These methods use blend organic sulfonic acid precasting process and sulfonation by sulfuric acid post-casting process (APS), blending organic sulfonic acid precasting process (AS) and sulfonation by sulfuric acid post-casting process (AP). The presence of organic sulfonic acid and the sulfonation were confirmed via FTIR spectra for the membranes. The membranes were characterized by proton conductivity, ion exchange capacity (IEC), [-SO3H] value, and water uptake. MFC is characterized by electrochemical polarization tests and power densities obtained from it were used to evaluate the efficiency of the membrane in the cell.
Zahraa Talib Khudhair, Mehdi Salih Shihab, and Baram Hamah-Ameen
Pleiades Publishing Ltd
The drug development process for Coronavirus disease (COVID-19) is the research process to create a preventive vaccine or therapeutic prescription drug to relieve the severity of 2019–2020 (COVID-19). In different stages of preclinical or clinical research, several hundred special scientific research centers, research organizations, and health agencies have developed and tried enormous numbers of vaccine candidates and new drugs for COVID-19 disease. In order to identify new therapies against COVID-19, several clinical trials have been in progress worldwide.
Mehdi Salih Shihab
Journal of Physics: Conference Series IOP Publishing
Coronavirus disease (COVID-19) drug development process is the research processing to develop a preventative vaccine or therapeutic prescription drug that would alleviate the severity of 2019-2020 (COVID-19) Several hundred of special scientific research centers, research groups, and health organizations were developing and trying huge numbers of vaccine candidates and potential drugs for COVID-19 disease in various stages of preclinical or clinical research Some clinical trials were in progress worldwide to find potential therapies against COVID-19 © Published under licence by IOP Publishing Ltd
Zahraa Talib Khudhair and Mehdi Salih Shihab
Surface Engineering and Applied Electrochemistry Allerton Press
Six new pyrazole derivatives were successfully prepared and investigated as corrosion inhibitors for mild steel in 1 M H2SO4 solution by weight loss measurements for 24 h at 30°C. It was observed that at higher inhibitor concentrations, the rate of corrosion decreases, the inhibition efficiency increases as well as the surface coverage degree. The values of the standard free energy of adsorption showed that all prepared pyrazole derivatives afford physisorption effects. The correlation between experimental results and theoretical data could be concluded by using semiempirical molecular orbital calculations for the six studied inhibitors. Theoretical calculations were used to understand the interaction nature between the metal surface and the organic molecules as a corrosion inhibitors.
Alaa Adnan Rashad, Nasreen Raheem Jber, and Mehdi Salih Shihab
Elsevier BV
Imran Fakhar, Nasry Jassim Hussien, Suhaila Sapari, Anmar Hameed Bloh, Siti Fairus Mohd Yusoff, Siti Aishah Hasbullah, Bohari Mohammad Yamin, Sahilah Abdul Mutalib, Mehdi Salih Shihab, and Emad Yousif
Elsevier BV
Abstract N1,N4-Bis{(2-hydroxyethyl)(methyl)carbamothioyl}terephthalamide (1A) was synthesized by reacting terephthaloyl chloride and ammonium thiocyanate and the product was reacted with 2-Methyl amino ethanol to afford the final product. The product was characterized by Infra Red, Nuclear Magnetic Resonance and Electrospray Ionization mass Spectrometric techniques. The crystal was obtained by recrystallization from DMSO by slow evaporation technique. The X-ray studies reveal that (1A) is crystallized in monoclinic system with space group P 21/n, a = 6.9727(9), b = 17.649(2), c = 8.2629(11), α = 90, β = 112.329(4), γ = 90. Z = 2 and V = 940.6(2). In the crystal structure, the molecules are linked by O(1) … H(1) … S(1), and O(1) … H(1) … O(2) intermolecular H-bonds forming a 3-D network. In addition, the antibacterial activities against four different strains of bacteria and theoretical evaluation for the stable geometries for (1A) has been performed using semi-empirical calculations of PM3 method.
Mehdi Honarvar Nazari, Mehdi Salih Shihab, Ling Cao, Eden Adele Havens, and Xianming Shi
Informa UK Limited
ABSTRACT A liquid mixture was developed from waste peony leaves through a zero-waste chemical/biological process. The inhibition effect of different concentrations of peony leaves derived solution (0–3 vol.%, PLS0-3) on C1010 carbon steel in 3.5 wt.% NaCl was investigated over time using electrochemical measurements. Chemical analyses were performed to reveal the main compounds of this inhibitor. Surface analyses together with water contact angle measurements were employed to study the characteristics of the steel surface affected. Semi-empirical calculations with PM3 method were used to find the relationship between molecular structure and inhibiting effect of PLS. The inhibitor was stable over time and its main active ingredients were C19H27N4O10P and C17H16N3O9P that adsorb onto the steel surface, block cathodic active sites, make the surface hydrophobic, decrease the surface free energy, and facilitate the formation of a passive layer. A good correlation was found between experimentally determined inhibition efficiency and theoretically calculated properties of PLS. GRAPHICAL ABSTRACT
M S Shihab and A F Mahmood
Portuguese Society of Electrochemistry
N-pyridinium salt derivatives (1–5) were prepared and investigated as corrosion inhibitors for mild steel in 1 M H2SO4 solution at 30°C for 24 h. The corrosion inhibiting action was studied using weight loss measurements. The results demonstrated that the corrosion rate decreases, inhibition efficiencies increase, and surface coverage degree increases with increasing inhibitor concentration. Inhibition efficiencies for prepared N-pyridinium salt derivatives have highest inhibiting efficiency for even low concentration. The values of ΔGads° showed physisorption effect for all prepared compounds. Molecular modeling systems were achieved for suggested inhibitors 1–5. Theoretical calculations could be used as a useful tool to obtain information for explaining the mechanism and nature of interaction between the metal surface and the organic molecule as a corrosion inhibitor.
Mehdi Salih Shihab, Abbas Hadi Alshukrawi, and Wedad Hamad Aldahhan
Pleiades Publishing Ltd
In the present work, sodium 4-[(4-formylbenzylidene) amino] benzoiate (4) was synthesized and its structure was confirmed using spectroscopic techniques. Prepared compound was successfully applied as a corrosion inhibitor for C1010 carbon steel in 3.5% NaCl solution at 25°C. Different electrochemical measurements such as linear polarization resistance (LPR), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were used to evaluate the suggested inhibitor (4). The results of different electrochemical measurements show that inhibition efficiencies obtained from EIS curves are in consistence with the results of potentiodynamic polarization and LPR measurements due to increase corrosion inhibition efficiency by increasing the concentration of organic inhibitor (4). Semi-empirical calculations with PM3 method were used to find relationship between molecular structure and inhibiting effect of suggested inhibitor (4).
Mehdi Salih Shihab, Mehdi Honarvar Nazari, and Laura Fay
Pleiades Publishing Ltd
In this work, pyridinium dibromide (2) was synthesized and its structure was confirmed using spectroscopic techniques. Compound (2) was successfully applied as a corrosion inhibitor for C1010 carbon steel in 3.5% NaCl solution at 25°C. Different electrochemical measurements such as potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were used to evaluate different concentrations of the suggested inhibitor (2). The results showed that inhibition efficiencies obtained from EIS curves are in consistence with the results of PDP at higher concentration 4.5 × 10–4 M. Semi-empirical calculations with PM3 method was used to find relationship between molecular structure and inhibiting effect of suggested inhibitor (2).
Mehdi Salih Shihab and Atheer Fadhil Mahmood
Pleiades Publishing Ltd
N-pyridinium salt derivatives (1–5) were prepared and investigated as corrosion inhibitors for mild steel in 1 M H2SO4 solution at 30°C for 24 h. The corrosion inhibiting action was studied using weight loss measurements. The results demonstrated that the corrosion rate decreases, inhibition efficiencies increase, and surface coverage degree increases with increasing inhibitor concentration. Inhibition efficiencies for prepared N-pyridinium salt derivatives have highest inhibiting efficiency for even low concentration. The values of ΔGads° showed physisorption effect for all prepared compounds. Molecular modeling systems were achieved for suggested inhibitors 1–5. Theoretical calculations could be used as a useful tool to obtain information for explaining the mechanism and nature of interaction between the metal surface and the organic molecule as a corrosion inhibitor.
Mehdi Salih Shihab and Hanan Hussien Al-Doori
Elsevier BV
Abstract [N-substituted] p-aminoazobenzene derivatives (1), (2), (3), (4) and (5) were prepared and investigated as corrosion inhibitors for mild steel in 1 M H2SO4 solution by weight loss measurements. It has been observed that the corrosion rate decreases, inhibition efficiencies increase and surface coverage degree increases with increasing inhibitor concentration. Inhibition efficiencies for prepared compounds were ordered: (1) > (2) > (5) > (4) > (3) with the highest inhibiting efficiency of 63% for 10−3 M. The values of Δ G ads o are showing physisorption effect for all prepared compounds. Semiempirical molecular orbital calculations for (1), (2), (3), (4) and (5) could be used as a useful tool to obtain information for explaining the nature of interaction between the metal surface and the organic molecule as a corrosion inhibitor.
Nasreen Raheem Jber, Alaa Adnan Rashad, and Mehdi Salih Shihab
Elsevier BV
Abstract In this work, the nematic liquid crystal (LC) N-(4′-methoxybenzylidene)-4-n-butylaniline (MBBA) was prepared and doped with different concentrations (0.025, 0.05, 0.06, 0.07, 0.08, and 0.1 wt.%) of multi-walled carbon nanotubes (CNTs) at room temperature to study the electric properties of (LC–CNTs) cell. The experimental results showed that capacitance of (LC–CNTs) cell became higher than that of pure LC cell. The dielectric permittivity is determined as a function of applied frequency (100 Hz to 100 kHz) at voltage (5 V); it is found that increasing concentration of CNTs (0.1 wt.%) led to increase in the real part dielectric constant and decrease in imaginary part for (LC–CNTs) cell compared with the pure liquid crystal. Also conductivity of (LC–CNTs) cell was increased with increasing concentration of CNTs more than 0.05 wt.%. Theoretical study was carried out by using PM3 method for stable geometries of a nematic liquid crystal molecule of MBBA assembled parallel on a molecule of single-walled carbon nanotube (CNT). The result showed that the interaction caused by π,π-stacking between MBBA molecule and the wall of CNT and that may lead to formation of the local short range orientation order by LC molecules on the surface of the CNT. The binding energy of the LC molecule on the CNT wall was within the typical van der Waals interaction.
Mehdi Salih Shihab
Springer Science and Business Media LLC
Quantum mechanical calculations (AM1, PM3, ab initio HF/3-21G, DFT(B3LYP/6-31G*) and MP2//(B3LYP/6-31G*) have been used to study the inverse-demand synchronous concerted Diels–Alder reactions between dimethyl-1,2,4,5-tetrazine-3,6-dicarboxylate (diene) and a variety of dienophiles (ethylene, cyclopentadiene, 1-hexene, cyclohexene). All the molecular structures (reactants, transition states, intermediates and adducts) were optimized using the semi-empirical AM1 method. The calculated energies and volumes showed that the cycloaddition reaction followed a mechanism involving the formation of an intermediate, elimination of N2, and a 1,3-hydrogen shift adduct. The reaction energies of the systems were obtained by using semi-empirical AM1 calculations and showed good agreement with the experimental data. In contrast, calculations of the reaction energies using PM3, HF/3-21G, DFT (B3LYP/6-31G*) and MP2//(B3LYP/6-31G* were in poor agreement with the experimental data. Compared to the experimental data, the activation energies were overestimated using AM1, PM3 and HF/3-21G, while they were underestimated using DFT (B3LYP/6-31G*) and MP2//(B3LYP/6-31G*).
Gulnara G. Iskhakova, Vladimir D. Kiselev, Rudi van Eldik, Achim Zahl, Mehdi S. Shihab, and Alexander I. Konovalov
Wiley
Solvent, salt and high pressure effects on the rate and equilibrium constants for the formation of tri-n-butylphosphoniumdithiocarboxylate at 298.2 K are reported. This equilibrium is shifted to the phosphobetaine in polar solvents, salt solutions and under high external pressure. The reaction volume changes dramatically on going from less polar diethyl ether (−69 cm3 mol−1) and tetrahydrofurane (THF) (−66 cm3 mol−1), to more polar acetonitrile (−39 cm3 mol−1) and acetone (−38 cm3 mol−1). Copyright © 2010 John Wiley & Sons, Ltd.
M. Shihab
Korean Chemical Society
Mehdi Salih ShihabAl-Nahrain University, College of Science, Department of Chemistry, Al-Jadrya, Baghdad-IraqE-mail: mehdi_shihab@yahoo.com Received February 15, 2008Study of computational model of the concerted Diels-Alder reaction between 9,10-dimethyl anthracene (asdonor) and tetracyanoethylene (as acceptor) in absence and in presence of aromatic solvents (benzene,mesitylene and hexamethylbenzene, as donors) using an AM1 semi-empirical method. AM1 method used tostudy the neutral charge transfer complex models that could be expected between donor and acceptor duringthe course of the concerted Diels-Alder reaction. Calculated enthalpies of reaction of the charge transfercomplexes models showed physical and chemical meaning for explain the effect of aromatic solvents on thekinetic process of concerted Diels-Alder reaction that contains tetracyanoethylene. Key Words : AM1 method, Neutral charge transfer complex, Concerted Diels-Alder reactionIntroductionThe Diels-Alder reaction which involving [4+2] cyclo-addition of diene to dienophile to give a six-member unsatu-rated ring, is occupied a wide space in the organic synthesis.Fukui and coworkers
Mehdi S. Shihab, Koji Kubota, Toru Takahashi, Yasushi Ohga, and Tsutomu Asano
The Chemical Society of Japan
Kinetic effects of pressure on a decay of a radical pair produced by UV irradiation of N,N'-dibenzyl-4,4'-bypyridinium dichloride were studied in acetonitrile (AN) and propylene carbonate (PC). Both in AN and PC, the process was accelerated by an increase in pressure indicating a considerable contraction of the solvation sphere during the activation. Furthermore, in PC, pressure-induced retardation was observed at P > 200 MPa and it was attributed to slow solvent thermal fluctuations at high pressures.
V. D. Kiselev, E. A. Kashaeva, M. S. Shihab, L. N. Potapova, and G. G. Iskhakova
Springer Science and Business Media LLC
The influence of the temperature and external pressure on the rate of the Diels—Alder reaction between 9,10-dimethylanthracene and maleic anhydride was studied in the series of solvents with wide intervals of viscosity (0.3—43.2 mPa s), dielectric constant (2—38), and internal pressure (3—8.8 kbar). At a standard pressure these properties of the solvent exert a weak and irregular effect on the reaction rate constant and activation enthalpy and entropy. The effect of the external pressure on the rate constant was studied in a high-pressure (up to 1 kbar) optical cell in acetonitrile and silicon oil and in a barostat cell (up to 6 kbar, toluene, silicon oil). Close values of the activation volume were obtained in all solvents. In toluene the reaction rate increases smoothly in the whole pressure interval. In more viscous silicon oil a similar dependence is observed up to 3 kbar, and the reaction rate decreases sharply with the further increase in the pressure and viscosity because of the diffusion control of the process.
Vladimir D. Kiselev, Alexandr I. Konovalov, Tsutomu Asano, Elena A. Kashaeva, Gulnara G. Iskhakova, Mahdi S. Shihab, and Margarita D. Medvedeva
Wiley
Volumes of activation, ΔV≠, and reaction, ΔV, partial molar volumes, , and enthalpies of solution, ΔsolH, were determined for tetracyanoethylene, cyclopentadiene, 1,3-butadiene, trans, trans-1,4-diphenyl-1,3-butadiene and their Diels–Alder adducts at 25 °C in some solvents of π- and n-donor type. The values of the activation and reaction volumes were exceptionally small in the former type of solvents. Large solvent effects on ΔsolHTCNE (up to 26 kJ mol−1), TCNE, ΔV and ΔV≠ (up to 11 cm3mol−1) were observed in aromatic solvents and these values are linearly correlated with each other. Poor correlations were found for n-donor solvents, but a linear dependence between ΔV and δr−nH (enthalpy of reaction) was obtained for all solvents. Copyright © 2001 John Wiley & Sons, Ltd.