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    Excess Volumetric Properties of Mixtures Epichlorohydrine Plus Acetone or Chloroform at 291.15 and 296.15 K
    (Interperiodica, 2003) Vural, U. S.; Yürük, H.; Muradoğlu, V.
    The excess molar volumes and densities of mixtures containing epichlorohydrine, acetone, and chloroforrn were determined at different temperatures by the Redlich-Kister equation. Chemical interaction and physical forces are very important influences on the excess molar volume of (epichlorohydrine + acetone or chloroform) mixtures. In addition, the variations of excess molar volumes were expressed as function of temperature.
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    The Interaction of Epoxy Toluene Oligomer Containing Chloromethyl Groups and P-Tert-Butylcalix[6]Arene
    (MARCEL DEKKER INC, 1995) Yıldız, S.; Vural, U. S.; Kurbanova, R.
    Oligomeric toluene material which has epoxy group (ETO) was prepared through reaction of toluene and epichlorohidrine in the presence of BF3. Epoxy toluene oligomere containing chloromethyl groups (ETOC) was synthesized from the treatment of NaOH and ETO for 6-8 hours. The macromolecular derivative of oligomer, (ETOC-I-6) was obtained from the reaction of ETOC and p-tert-butylcalix[6]arene (I-6) in the presence of CH3ONa. When the concentration of ETOC is greater than I-6, the reaction was observed as pseudo first order, benzene was used as solvent. The activation energy and rate constant of the reaction were calculated as 25.082 kj . mol(-1) and 3.155.10(-5) s(-1), respectively. The amounts of chlorine in ETOC-I-6 was determined 6.37% by Schoniger Method, and its molecular weight was determined as 2778.84 g . mol(-1) by cryoscopic method using benzene as solvent.
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    Kinetic Study of Ligand Exchange Reaction of Anions as Ligands on DAE-sporopollenin
    (ACADEMIC PRESS INC JNL-COMP SUBSCRIPTIONS, 1996) Ersöz, M.; Vural, U. S.; Yiğitoğlu, M.; Sezgin, M.
    The specific rate coefficients and ligand sorption isotherms of Br and I- as ligands on diaminoethyl-sporopollenin were determined as a function of pH and temperature between 20 and 60 degrees C. The ligand exchange rates were measured just after the rapid mixing of the ligand solution with the resin suspension. The data have also been analyzed to obtain activation parameters Delta G, Delta H, and Delta S for reaction in the corresponding mixture. A single ligand-exchange process was observed; the sorption of ligand increased with decreasing pH and hydrated radius of ligands and increasing temperature. A reaction mechanism which describe the ligand exchange reaction is proposed.
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    Transport Studies of Amino-Acids Through a Liquid Membrane System Containing Carboxylated Poly(Styrene) Carrier
    (ELSEVIER SCIENCE BV, 1995) Ersoz, M.; Vural, U. S.; Okdan, A.; Pehlivan, E.; Yıldız, S.
    Transport mechanisms have been studied for amino acids such as p-amino benzoic acid and phenylalanine moving through a bulk organic liquid membrane system containing carboxylated poly( styrene) carrier. The transport in this system, in which one side of the membrane was acidic and the other side was alkaline, was influenced significantly by the initial H+ ion concentration on the acidic side. The passage of amino acids through the organic bulk liquid membrane was governed by an electrochemical interaction between carboxyl groups in the membrane and transporting materials.
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    Transport Studies of Iodine Through Liquid Membrane System
    (JOHN WILEY & SONS INC, 1996) Vural, U. S.; Ersöz, M.
    Transport of iodine by a charge-transfer mechanism through a bulk organic liquid membrane system containing calixarene based on donor-type carriers was studied. It was found that the transport of iodine is facilitated by n-donor carriers depending on the pH of the source phase. The color of iodine solutions on the source side turned from brown to colorless. The passage of iodine through the organic bulk liquid membrane was governed by donor-acceptor interaction between n-donor atoms in the carrier and sigma-acceptor (iodine atoms) and by the diffusion of an n-sigma-type charge-transfer complex in the membrane followed to release by the Lewis acid-base interaction in the aqueous phase. The transport by the new carrier arises both from the different extraction equilibrium constants between the aqueous phase and donor-acceptor interaction with iodine and the carrier in the organic phase.