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      • Open Access Article

        1 - Matrix analysis of corrosion inhibition phenomena: Theoretical technique for inhibitor prediction and pre-selection
        Mohsen Lashgari Mohammad-Reza Arshadi Gholam-Abbas Parsafar
        Matrix Analysis of Corrosion Inhibition Phenomena (MACIP), in which an inhibitor isconsidered as a point in a multi-dimensional virtual efficiency space, was performed on somepyridine derivatives. The needed molecular parameters such as HOMO and LUMO energylevels, charg More
        Matrix Analysis of Corrosion Inhibition Phenomena (MACIP), in which an inhibitor isconsidered as a point in a multi-dimensional virtual efficiency space, was performed on somepyridine derivatives. The needed molecular parameters such as HOMO and LUMO energylevels, charge densities on hetero atom, dipole moment, heat of formation, and total energyvalues were obtained by means of semi-empirical quantum chemical methods; such as the AM1,MNDO, MINDO/3, and PM3. The obtained results for 3,5- dimethyl pyridine and 2,4- dimethylpyridine reveal out the fact that the last molecule is a better corrosion inhibitor as indicated inliterature. Manuscript profile
      • Open Access Article

        2 - Determination of lead and cadmium in water samples by cloud point extraction prior to flame atomic absorption spectrometry determination
        Yaping Ding Li Li Ruixiang Bian Dongsheng Zhao,
        Pb and Cd in water samples were determined by cloud point extraction (CPE) with sodiumdiethyldithiocarbamate (DDTC) as the chelating agent and octylphenoxypolyethanl (Triton X-114) asthe surfactant prior to flame atomic absorption spectrometry (FAAS) determination. The More
        Pb and Cd in water samples were determined by cloud point extraction (CPE) with sodiumdiethyldithiocarbamate (DDTC) as the chelating agent and octylphenoxypolyethanl (Triton X-114) asthe surfactant prior to flame atomic absorption spectrometry (FAAS) determination. The main factorsof affecting the extraction and detection processes were optimized. The preconcentration of 10 mL ofstandard solutions gave enhancement factors of 35 and 75 and the detection limits of 9.41 and 0.40ng mL-1 for Pb and Cd, respectively. The proposed method was applied satisfactorily to thedetermination of Pb and Cd in seawater and lake water. Good agreement was obtained between theadded and measured analyte amounts through the recovery of experiments. Manuscript profile
      • Open Access Article

        3 - Determination of e ω , e e x ω , e B , and e α using potential energy functions for heteronuclear diatomic molecules via spreadsheet program
        Saleh Bagheri
        In order to represent the potential energy function over the whole range of R, many potentialenergy functions have been proposed. In the present paper, we employ many potential energyfunctions, to use Numerov method for solving the nuclear Schrödinger equation for More
        In order to represent the potential energy function over the whole range of R, many potentialenergy functions have been proposed. In the present paper, we employ many potential energyfunctions, to use Numerov method for solving the nuclear Schrödinger equation for the IFmolecule, as an example of a heteronuclear diatomic molecules. Then we determine thespectroscopic constants eω , e e x ω , e B , and eα of the IF molecule from vibrational and vibrationrotationlevels obtained from solution of the nuclear Schrödinger equation. Finally, bycomparison of obtained values with the experimental ones, their accuracy rate is determined aswell as their deviation percentages from experimental values. Manuscript profile
      • Open Access Article

        4 - Arylazo derivatives of some fluorinated β-diketones and their metal complexes
        Muhammed Basheer Ummathur Krishnannair Krishnankutty Damodaran Kamalakshy Babu Philip Marina Philip
        Phenylazo and benzothiazolylazo derivatives of trifluoroacetylacetone andhexafluoroacetylacetone have been synthesized and characterized. Analytical and spectral datarevealed the existence of phenylazo derivatives in the intramolecularly hydrogen-bonded ketohydrazonefor More
        Phenylazo and benzothiazolylazo derivatives of trifluoroacetylacetone andhexafluoroacetylacetone have been synthesized and characterized. Analytical and spectral datarevealed the existence of phenylazo derivatives in the intramolecularly hydrogen-bonded ketohydrazoneform while the benzothiazolylazo derivatives in the azo-enol form. The monobasicbidentate coordination of the phenylazo derivatives and monobasic tridentate coordination of thebenzothiazolylazo derivatives in their Ni(II), Cu(II), Zn(II) and Pd(II) complexes have beenestablished by analytical and spectral data. Manuscript profile
      • Open Access Article

        5 - Numerical analysis of the optimal catalyst distribution in created unsteady state conditions
        Yacine Benguerba Brahim Djellouli Lemnouer Chibane Lahcene Bencheikh
        The determination of the optimal distribution of the catalytic activity profile, whichmaximizes the catalytic effectiveness, in created unsteady state conditions, is analyzed andtreated numerically for the case of a simple reaction. It was proven that the modulation, of More
        The determination of the optimal distribution of the catalytic activity profile, whichmaximizes the catalytic effectiveness, in created unsteady state conditions, is analyzed andtreated numerically for the case of a simple reaction. It was proven that the modulation, of thetemperature and the reactant concentration of the external bulk fluid, leads to a considerableincrease of the catalytic effectiveness. The optimal active element distribution is a Dirac- δfunction i.e. all the catalyst must be deposited at a specific distance from the center of thecatalytic pellet. It was shown that this optimal position changes with time in a sinusoidal manner.This purpose can be achieved by the use of ultrasounds to artificially control the activity profile. Manuscript profile
      • Open Access Article

        6 - Tautomeric behaviors of 5-arylazobarbituric acids in different concentrations
        Nader Noroozi Pesyan Jabbar Khalafy Karim Akbari Dilmaghani, Saeed Rastgar, Zahra Malekpoor, Mina Mohammadzadeh
        The NMR spectra of azo dyes, 5-arylazobarbituric (5a-g), 5-arylazo-1,3-dimethylbarbituric(6a-g) and 5-arylazothiobarbituric acids (7a-g) were studied in DMSO-d6 in differentconcentrations. An intramolecular hydrogen bond was observed and indicating that thehydrazone for More
        The NMR spectra of azo dyes, 5-arylazobarbituric (5a-g), 5-arylazo-1,3-dimethylbarbituric(6a-g) and 5-arylazothiobarbituric acids (7a-g) were studied in DMSO-d6 in differentconcentrations. An intramolecular hydrogen bond was observed and indicating that thehydrazone forms is mostly predominant. The peak of the hydrazone proton was severelybroadened and its chemical shift appeared at down field due to intramolecular hydrogen bond.Existence of nitro group at ortho-position on phenyl ring caused the chemical shift value of theproton of hydrazone form in 5a-7a to be more deshielded than other hydrazone protons in 5bg−7b-g due to bifurcated intramolecular hydrogen bond and anisotropic ring-current effect. Dyes6 shows two tautomers in NMR time scale at low concentration in DMSO-d6. Manuscript profile
      • Open Access Article

        7 - Synthesis of nanosized TiO2 powder by Sol-Gel method in acidic conditions
        Parvain Gharbani Ali Mehrizad, Samad Motameni Tabatabii
        The preparation of nano-sized TiO2 by titanium tetraisopropoxide (Ti(OiPr)4) via sol-gelmethod using acid as a catalyst is investigated and the optimized conditions concerning theproportional amount of acid, water, alcohol is established by XRD and SEM. The effect ofcal More
        The preparation of nano-sized TiO2 by titanium tetraisopropoxide (Ti(OiPr)4) via sol-gelmethod using acid as a catalyst is investigated and the optimized conditions concerning theproportional amount of acid, water, alcohol is established by XRD and SEM. The effect ofcalcination temperature on phase transformation of TiO2 (rutile, anatase and brookite) wasdetermined by XRD. The smallest grain size of TiO2 powder we have obtained is 25 nm foranatase at 400 ºC by controlling the acidity and the mole ratio of starting materials. Manuscript profile
      • Open Access Article

        8 - Kinetic of iodination of phenol and substituted phenols by pyridinium iodochloride in methanol
        Yeshwant B. Vibhute Sandeep V. Khansole
        The kinetics of iodination of the phenol and substituted phenols using pyridiniumiodochloride in methanol has been studied under varying conditions. The rates show first orderkinetics each in pyridinium iodochloride and phenols. The rates of reactions are measured atdif More
        The kinetics of iodination of the phenol and substituted phenols using pyridiniumiodochloride in methanol has been studied under varying conditions. The rates show first orderkinetics each in pyridinium iodochloride and phenols. The rates of reactions are measured atdifferent temperature and activation parameters for all phenols computed. Hammett plot is foundto be valid and the corrletion between the enthalpies and free energies of activations isreasonably linear with an isokinetic temperature 359.55 K. Similarly log A values of all thephenols are optimized corresponding to Ea of phenols through the equation, log A = log kobs + Ea/ 2.303 RT. Manuscript profile