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Farrokh Gharib Ali Shamel Fatemeh Jaberi Ali Farajtabar 《Journal of solution chemistry》2013,42(5):1083-1095
The solvatochromic properties of the free base and the protonated 5,10,15,20-tetrakis(4-trimethyl-ammonio-phenyl)-porphine tetratosylate (TTMAPP) were studied in pure water, methanol, ethanol, 2-propanol, and their corresponding aqueous mixtures. The correlation of the empirical solvent polarity scale (E T) values of TTMAPP with composition of the solvents were analyzed by the solvent exchange model of Bosch and Roses to clarify the preferential solvation of the probe dyes in the binary mixed solvents. The solvation shell composition effects in preferential solvation of the solute dyes were investigated in terms of both solvent–solvent and solute–solvent interactions and also the local mole fraction of each solvent composition was calculated in the cybotactic region of the probe. The effective mole fraction variation may provide significant physicochemical insights in the microscopic and molecular level of interactions between TTMAPP species and the solvent components and, therefore, can be used to interpret the solvent effect on kinetics and thermodynamics of TTMAPP. 相似文献
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Ionic Strength Dependence of Formation Constants and Complexation of Glutamine with Dioxovanadium(V)
Gharib F. Aghaei H. Shamel A. Taghvamanesh A. Shafiee G. 《Russian Journal of Coordination Chemistry》2003,29(6):408-413
The dependence of L-glutamine protonation and its complexation with dioxovanadium(V) on ionic strength (I) is reported in sodium perchlorate solution as a background salt. The measurements have been performed at 25 ± 0.1°C and various ionic strengths in the range 0.1 to 1.0 mol/l, using a combination of potentiometric and spectrophotometric techniques. The overall analysis of the present and the previous data dealing with the determination of stability constants at different ionic strengths allowed us to obtain a general equation, by which a formation constant determined at a fixed ionic strength can be calculated, with a good approximation, at another ionic strength, if 0.1 I 1.0 mol/l (NaClO4). 相似文献
3.
A selective fluorescent chemosensor was prepared by anchoring pyridine-2-carbaldehyde Schiff base ligand onto mesochannels of organically modified SBA-15 mesoporous silica. The resulting organic-inorganic hybrid mesoporous chemosensor was characterized by X-ray diffraction, Fourier transform IR spectroscopy, transmission electron microscopy, UV-visible diffuse reflectance spectra, and photoluminescence spectra. All the results support the idea that successive attachment of the ligand moiety onto one-pot-modified mesoporous scaffold has not altered its basic hexagonally arranged structure. Upon introducing trace amounts of zinc ions into aqueous solution, remarkable enhancement in the fluorescence was observed. 相似文献
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Russian Journal of Applied Chemistry - In the authors’ list of the title section T. Salemnush is the fi rst author and A. Shamel is the coauthor and corresponding person. 相似文献
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Farrokh Gharib Ali Shamel Sahar Mohajeri 《Russian Journal of Inorganic Chemistry》2010,55(10):1651-1656
The dependence on ionic strength of protonation of nitrilotriacetic acid and its complexation with W(VI) is reported in sodium
perchlorate, sodium nitrate and sodium chloride solutions as background salts. The measurements have been performed at 25°C
and various ionic strengths in the range 0.1–1.0 mol dm−3, using a combination of potentiometric and spectrophotometric techniques. The overall analysis of the present and the previous
data dealing with the determination of stability constants at different ionic strengths allowed us to obtain a general equation,
by which a formation constant determined at a fixed ionic strength can be calculated, with a good approximation, at another
ionic strength, if 0.1 ≤ ionic strength ≤ 1.0 mol dm−3 sodium perchlorate, sodium nitrate or sodium chloride. 相似文献
6.
Ali Shamel Afsaneh Saghiri Fatemeh Jaberi Ali Farajtabar Faezeh Mofidi Saeid Abedini Khorrami Farrokh Gharib 《Journal of solution chemistry》2012,41(6):1020-1032
The acid-base equilibria of glycine have been studied in different aqueous solutions of methanol and ethanol (0?C45?% v/v) using a potentiometric method. In this study, the macro and micro protonation constants of the amino acid and its tautomeric constant have been determined at 25?°C and constant ionic strength (0.1 mol?dm?3 NaClO4). The protonation and the tautomeric constants of glycine in different binary mixtures were analyzed in terms of the Kamlet, Abboud and Taft (KAT) parameters. Single-parameter correlations of the constants versus ?? (hydrogen-bond donor acidity), ?? (hydrogen-bond acceptor basicity) and ?? ? (dipolarity/polarizability) are poor in all solutions. Multi-parameter correlations show better results, but dual-parameter correlations represent significant improvements with regard to the single- and multi-parameter models. Linear correlation is observed when the experimental protonation constant values are plotted versus the calculated ones when the KAT parameters are considered. Finally, the results are discussed in terms of the effect of the solvent on protonation and tautomeric constants. 相似文献
7.
Rezaei-Aghdam Elnaz Shamel Ali Khodadadi-Moghaddam Mohammad Ebrahimzadeh Rajaei Gholamreza Mohajeri Sahar 《Research on Chemical Intermediates》2021,47(5):1759-1774
Research on Chemical Intermediates - In the present study, TiO2, ZnO, and CTAB-stabilized Fe3O4 nanocomposite were successfully synthesized and employed for the removal of yellow 145 dye from... 相似文献
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