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Abstract  

Tetra-n-undecylcalix[4]resorcinarene forms solid adducts with secondary and tertiary amines. Thermal decomposition of these complexes was investigated by means of thermogravimetry (TG) and differential scanning calorimetry (DSC). It was found that deamination of complexes occurs as multi-step process. The stoichiometry of complexes was evaluated on the basis of TG studies and total heats of deamination were calculated from DSC measurements.

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Journal of Thermal Analysis and Calorimetry
Authors: A. G. Souza, I. P. Silva Filho, J. C. O. Santos, L. M. Nunes, I. M. G. Santos, L. E. B. Soledade, and M. M. Conceiçăo
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Sass-Kiss, A., Szerdahelyi, E. & Hajós, Gy. (2000): Study of biologically active amines in grapes and wines by HPLC. Chromatographia , 51 , 316-320. Study of biologically active amines

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References BÓKa , B. , AdÁNyi , N. , VirÁG , D. , Sebela , M. & Kiss , A. ( 2012 ): Spoilage detection with biogenic amine

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Acta Alimentaria
Authors: K. Berisha, H. Bytyçi, Zs. Mednyánszky, E. Kiss, and L. Simon-Sarkadi

, spermine, putrescine, and cadaverine, are important in the regulation of nucleic acid function and protein synthesis and in the stabilisation of membranes ( Kalac and Krausová , 2005 ). Biogenic amines (BA) mainly form as a result of microbial

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. & Holzapfel, W. (1994): Biogenic amines and their production by microorganisms in food. Trends Fd Sci. Technol. , 5 , 42–49. Holzapfel W. Biogenic amines and their production by

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. Csaba , G. , Kovács , P. , Pállinger , É. : Edac fixation increases the demonstrability of biogenic amines in the unicellular Tetrahymena: A flow cytometric and confocal microscopic comparative analysis . Cell Bol Int 30 , 345 – 348 ( 2006

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Abstract  

Crystalline lamellar titanium phenylphosphonate was intercalated with n-alkylmonoamines, H3C(CH2)n-NH2 (n=0 to 3), which decomposed on heating in four distinct stages. The lamellar compound was calorimetrically titrated with ethanolic amine solution at 298.150.02 K and the enthalpy, Gibbs free energy and entropy were calculated. with the exception of butylamine, the enthalpic values increased with the number of carbon atoms in the amine chain, as -16.200.22; -18.700.19; -23.700.24 and -18.300.22 kj mol-1, from n=0 to 3. The exothermic enthalpic values reflected a favorable energetic process of intercalation, when the solvated ethanol molecules on inorganic matrix are progressively substituted by solute. The negative gibbs free energy results supported the spontaneity of the reactions and the positive favorable entropic values are in agreement with the increase of solvent molecules in the reaction medium, as the amine becomes bonded to the crystalline lamellar inorganic matrix.

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Introduction Biogenic amines, which are a general term for a class of biologically active nitrogen-containing organic compounds with low molecular weight, have been found in various foods such as cheese, wine, meat and aquatic products [ 1 ]. It has

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