• فهرس المقالات Complexation

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        1 - Complexation of alkali metal ions by totrapropary-monoamine and tetrabutoxytriamine utak] arenes
        Noushin Osouleddini Karim Zare
        The complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions Lit Nat, Kt RIC and Cs+ in methanol-chloroform mixture have been ev أکثر
        The complexive abilities of 5,11,17-tddert-butyl-23 amino-25.26,27,28-tet3propoxy-calix[4]arere and5,1127-tri-amino-23 acelyktert-butylamide-25,26,27,28-tetrabutoxy-calixplarene towards alkali metalions Lit Nat, Kt RIC and Cs+ in methanol-chloroform mixture have been evaluated at 25 °C, using UVVis spectrophotometric techniques. The results showed that the hgands are capable to complex with all ofthe alkali cations by LI metal to ligand ratios The selectivity presented considering the calculatedformation constants are in the order Li* > Na > C, Kb+ > Cs for the ligands تفاصيل المقالة
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        2 - Ionic Strength Dependence of Formation Constants: Complexation of Dioxouranium (VI) with Aspartic Acid
        Farrokh Gharib Karim Zare Ramin Cheraghali
        The dependence on ionic strength of protonation of L-aspartic acid and its complexation withdioxouranium(VI) is reported in sodium perchlorate solution as a background salt. The measurementshave been performed at 25 ± 0.1 °C and various ionic strengths in the أکثر
        The dependence on ionic strength of protonation of L-aspartic acid and its complexation withdioxouranium(VI) is reported in sodium perchlorate solution as a background salt. The measurementshave been performed at 25 ± 0.1 °C and various ionic strengths in the range 0.1 to 1.0 mol dm-3, using acombination of potentiometric and spectrophotometric techniques. The overall analysis of the present andthe previous data dealing with the determination of stability constants at different ionic strengths allowedus to obtain a general equation, by which a formation constant determined at a fixed ionic strength can becalculated, with a good approximation, at another ionic strength, if 0.1 ≤ ionic strength ≤ 1.0 mol dm-3sodium perchlorate. تفاصيل المقالة
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        3 - Complexation of Calcium and Barium Cations by Calix[4]arene-bis-crown-6
        Poupak Khazaeli-Parsa Mehran Aghaie Karim Zare Azar Bouzaripour
        In this study the binding abilities of 1,3-calix[4]biscrown-6 (L) toward Ba2+ and Ca2+ have beenestablished in methanol by spectrophotometric measurements at 25±0.1 °C and 0.01 M ionicstrength, and with using Specfit computer program; stability constants for أکثر
        In this study the binding abilities of 1,3-calix[4]biscrown-6 (L) toward Ba2+ and Ca2+ have beenestablished in methanol by spectrophotometric measurements at 25±0.1 °C and 0.01 M ionicstrength, and with using Specfit computer program; stability constants for 2 : 1, metal : ligandcomplexes has been estimated تفاصيل المقالة
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        4 - Ionic str4ength dependence of formation constants, complexation of Glycine with dioxouranium (VI) Ion
        Farrokh Gharib Ali Shamel Farbod Lotfi
        The dependence on ionic strength of protonation of glycine and its complexation with dioxouranium (VI) is reported in sodium perchlorate and sodium chloride solutions as background salts. The measurements have been performed at 25±0.1°C and various ionic stre أکثر
        The dependence on ionic strength of protonation of glycine and its complexation with dioxouranium (VI) is reported in sodium perchlorate and sodium chloride solutions as background salts. The measurements have been performed at 25±0.1°C and various ionic strengths in the range 0.1 to 1.0 mol , 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 strengths can be calculated, with a good approximation, at another ionic strength, if 0.1 ionic strength 1.0 mol sodium perchlorate or sodium chloride. تفاصيل المقالة
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        5 - Study on the Interaction of Dioxovanadium(V) with Nitrilotriacetic Acid at Different Ionic Strengths by Using Extended Debye-Hiickel Equation
        K. Zare S. Rezaienejad
        In this research complexation of dioxovanadium(V) with nitrilotriacetic acid (NTA) at differentionic strengths (0.1 to 1.0 mol dm-3) of sodium perchlorate as supporting electrolyte and pH rangeof 1.00-2.50 at 25 °C has been investigated by a combination of potentiom أکثر
        In this research complexation of dioxovanadium(V) with nitrilotriacetic acid (NTA) at differentionic strengths (0.1 to 1.0 mol dm-3) of sodium perchlorate as supporting electrolyte and pH rangeof 1.00-2.50 at 25 °C has been investigated by a combination of potentiometric and UVspectrophotometric measurements. Stability constants of two species, V0211L- and VO2H2L havebeen calculated. Ionic strength dependence semi-empirical parameters for the dissociation andstability constants were derived on the basis of extended Debye-Htickel type equation. تفاصيل المقالة
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        6 - Interaction of Thallium (I) with Cytidine 5-Monophosphate in Different Ionic Strengths and Various Media
        Farhoush i Kian Farrokh Gharib
        The formation constants of the species formed in the systems H+ + cytidine 5-monophosphate (CMP)and H+ + cytidine 5-monophosphate + Tl (I) ion have been determined in aqueous solution in a widepH range of 1.5 to 10.5 at 25 °C and different ionic strengths ranging أکثر
        The formation constants of the species formed in the systems H+ + cytidine 5-monophosphate (CMP)and H+ + cytidine 5-monophosphate + Tl (I) ion have been determined in aqueous solution in a widepH range of 1.5 to 10.5 at 25 °C and different ionic strengths ranging from 0.1 to 1.5 moldm-3NaClO4, NaNO3, and NaCl using potentiometric-spectrophotometric technique. The composition ofthe complexes was specified and was shown that thallium ion forms mononuclear two 1:1 complexeswith CMP. The general trend for the protonation constants of CMP and its complexes with thallium(I) are in the order of NaClO4> NaNO3> NaCl in different ionic media. The dependence of formationconstants on ionic strength are described by a Debye-Huckel type equation and interpreted for thevarious supporting electrolytes. تفاصيل المقالة
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        7 - Synthesis and Solution Complexation Studies of a new Schiff base Ligand
        Mahmood Payehghadr Farzaneh Nourifard Mehdi Kalhor Chiman Shahoei
        A new Schiff base ligand, 2,2'-{pyridine-2,6-diylbis[nitrilo(E)methylylidene]}bis(4 bromophenol),has been synthesized by reaction of the 2,6-diamino pyridine with 5-bromo salicylaldehyde at ethanolunder refluxing. The structure of the synthesized compound resulted from أکثر
        A new Schiff base ligand, 2,2'-{pyridine-2,6-diylbis[nitrilo(E)methylylidene]}bis(4 bromophenol),has been synthesized by reaction of the 2,6-diamino pyridine with 5-bromo salicylaldehyde at ethanolunder refluxing. The structure of the synthesized compound resulted from the IR, 1HNMR, MS andUV spectroscopy and elemental analysis data. Formation Constant (kf) value of it’s complexes withCu2+, Ni2+, Cd2+, Co2+ and Hg2+ has been determined Conductometrically. The formation constants ofthe resulting 1:1 complexes have been calculated from the computer fitting of the molar conductance- mole ratio data at different temperatures. The stability of the complexes to vary in acetonitrilesolvent was in the order of Cu2+ > Cd2+ > Co2+ > Hg2+ > Ni2+. The enthalpy and entropy changes ofthe complexation reactions have been evaluated from the temperature dependence of formationconstants. تفاصيل المقالة
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        8 - Determination of Trimethoprim Based on Charge-Transfer Complexes Formation
        Azar Bagheri Sedigheh Rahimi khomami
        A spectrophotometric study concerning the interaction between Trimethoprim (TMP) ,Sulfamethoxazole (SFMx), as n-donor and 2,3-dichloro-5,6- dicyano-P-benzoquinine (DDQ) and chloranilic acid (CA) as π-acceptor were been performed at 25°C. The results of interactio أکثر
        A spectrophotometric study concerning the interaction between Trimethoprim (TMP) ,Sulfamethoxazole (SFMx), as n-donor and 2,3-dichloro-5,6- dicyano-P-benzoquinine (DDQ) and chloranilic acid (CA) as π-acceptor were been performed at 25°C. The results of interaction of CA and DDQwith TMP indicate the formation of a 1:1, 1:2, charge transfer complexes through non equilibrium reactions. In the case of SFMx, the formation of 1:2 (SFMx/DDQ, SFMx /CA) charge-transfer complexes is confirmed. The formation constants of the equilibrium step were evaluated from the computer fitting of the absorbance-mole ratio data. Also, this study was carried out to simultaneously determine quantitatively TMP in Cotrimoxazole. The complexes of TMP with DDQ and chloranilic acid absorbed maximally in 512 and 585, respectively. تفاصيل المقالة
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        9 - Catalytic Effects of Carbon Nanotubes on Complexation of Some Amino Acids via Cobalt Cation Catalyst
        Masoumeh Piryaei
        In this research, investigation of the adsorption isotherms and the effect of solution conditions such as pH and concentration of complexation of some amino acids with cobalt(II) nitrate six-hydrate upon multi-wall type carbon nanotube (CNT) were done. The adsorption ca أکثر
        In this research, investigation of the adsorption isotherms and the effect of solution conditions such as pH and concentration of complexation of some amino acids with cobalt(II) nitrate six-hydrate upon multi-wall type carbon nanotube (CNT) were done. The adsorption capacity of complexation of amino acids onto the surface of carbon nanotube increased with the pH from acidic to alkaline. At pH = 9 the affinity order of the complexation of amino acids towards carbon nanotube is L-arginine > L-phenylalanine > L-asparagine > L-methionine > L-cysteine > glycine > L-alanine > L-valine > L-histidine. The curves have an important role in the design and optimization of the unit operations such as preservation, drying storing packaging and mixing. The adsorption equilibrium isotherms were fitted by Freundlich, Langmuir and Temkin models, but the Freundlich model is better than other models because is does not assume the surface as homogeneous with respect to adsorption energies and also the r2 value indicates the goodness of fit between the data and the isotherm. تفاصيل المقالة