NISCAIR Online Periodicals Repository Collection: IJC-A Vol.48A(11) [November 2009]

Detection of tight ion-pair in some novel lipopathic oxidants from the monolayer at air-water interface

Thu, 29 Oct 2009 22:58:59 GMT

Title: Detection of tight ion-pair in some novel lipopathic oxidants from the monolayer at air-water interface

Authors: Mishra, B K; Sahu, Sandhyamayee; Pradhan, S; Patel, Sabita

Abstract: From the isotherms of surface pressure and area of cetyltrimethylammonium dichromate, permanganate and ceric nitrate, the anchoring area on water-air interface for each oxidant has been determined by spreading as Langmuir monolayer. The area/molecule of these oxidants with a common amphiphilic counterion, i.e., cetyltrimethylammonium ion, depends on the size of the anion counterpart indicating the existence of contact ion pair between CTA⁺ and the anionic group in aqueous medium. However, in aqueous acetic acid subphase, the decrease in area/molecule of cetyltrimethylammonium dichromate indicates dissociation of the constituting ions.

Page(s): 1527-1531

Inclusion complexation of 3,5-dihydroxybenzoic acid with β-cyclodextrin at different pHs

Thu, 29 Oct 2009 22:58:59 GMT

Title: Inclusion complexation of 3,5-dihydroxybenzoic acid with β-cyclodextrin at different pHs

Authors: Siva, S; Sankaranarayanan, R K; Prabhu, A Antony Muthu; Subramanian, V K; Rajendiran, N

Abstract: Effect of -cyclodextrin on the absorption and fluorescence spectra of 3,5-dihydroxy benzoic acid has been studied in buffer solutions of different pHs (1, 7, 10). The study reveals that in all the studied pHs, DHB forms 1:1 inclusion complex. The hydroxyl group is present in the interior part of the -CD cavity and carboxyl group is present in the hydrophilic part of the -CD cavity. Dual luminescence is observed in pH~1 and pH~7 solutions which shows that intramolecular charge transfer is present in these pHs. The broad spectral maximum at pH~10 indicates intramolecular proton transfer in DHB.

Page(s): 1515-1521

Studies of viscosities of dilute solutions of alkylamines in non-electrolyte solvents. V. Alkylamines in toluene and benzene at 303.15 K

Thu, 29 Oct 2009 22:58:59 GMT

Title: Studies of viscosities of dilute solutions of alkylamines in non-electrolyte solvents. V. Alkylamines in toluene and benzene at 303.15 K

Authors: Oswal, S L; Ijardar, S P

Abstract: Viscosities of dilute solutions of n-propylamine, n-butylamine, di-n-propylamine, di-n-butylamine, tri-n-propylamine and tri-n-butylamine in toluene, and of tri-n-butylamine in benzene, have been measured at 303.15 K. The values of viscosity deviations are negative for all the amine solutions and their magnitude increases with the increase in concentration of alkylamine. The specific viscosities and excess Gibbs energy of activation of viscous flow, based on Eyring's theory of absolute reaction rates, are of varying magnitude and sign depending upon the viscosities and type and nature of solute and solvent molecules. The specific viscosities have been analyzed in terms of Herskovits and Kelly equation and Nakagawa equation. The change in Gibbs activation energy and the heat of solution per mole of solute (alkylamine) at infinite dilution in cyclohexane, benzene and toluene solutions have been calculated in terms of the transition state theory.

Page(s): 1501-1509

Synthesis and characterization of complexes of Fe(III), Co(III), Ni(II), Cu(II), Zn(II) and UO₂²⁺with p-tert-butylcalix[4]arene bearing two imine pendants linked through salicylyl moiety at the lower rim

Thu, 29 Oct 2009 22:58:59 GMT

Title: Synthesis and characterization of complexes of Fe(III), Co(III), Ni(II), Cu(II), Zn(II) and UO₂²⁺with p-tert-butylcalix[4]arene bearing two imine pendants linked through salicylyl moiety at the lower rim

Authors: Dey, Mishtu; Chinta, Jugun Prakash; Long, Gary J; Rao, Chebrolu P

Abstract: Metal ion complexes of the double-armed p-tert-butylcalix[4]arene derivative possessing imine functionality linked through salicylyl moiety at the lower rim has been synthesized for the first time and characterized by analytical, spectral and magnetic methods. The 1, 3- di-calix[4]arene-imine conjugate exhibits variable coordination behavior, from tetradentate to hexadentate, depending upon the metal ion to which it is bound, by always acting as di-anionic. While it uses both the ether oxygens of the pendants to coordinate in the case of Fe(III), Co(III) and Ni(II) complexes, it uses only the pendant salicylidene moieties in the case of Cu(II) and Zn(II) complexes. The Zn(II) complex catalysis ester hydrolysis through the formation of Zn(II)-hydroxo species.

Page(s): 1484-1491

NISCAIR Online Periodicals Repository Collection: IJC-A Vol.48A(11) [November 2009]

Detection of tight ion-pair in some novel lipopathic oxidants from the monolayer at air-water interface

Inclusion complexation of 3,5-dihydroxybenzoic acid with β-cyclodextrin at different pHs

Studies of viscosities of dilute solutions of alkylamines in non-electrolyte solvents. V. Alkylamines in toluene and benzene at 303.15 K

Synthesis and characterization of complexes of Fe(III), Co(III), Ni(II), Cu(II), Zn(II) and UO22+ with p-tert-butylcalix[4]arene bearing two imine pendants linked through salicylyl moiety at the lower rim

Synthesis and characterization of complexes of Fe(III), Co(III), Ni(II), Cu(II), Zn(II) and UO₂²⁺with p-tert-butylcalix[4]arene bearing two imine pendants linked through salicylyl moiety at the lower rim