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. Rezaei Behbehani , G , Divsalar , A , Saboury , AA , Faridbod , F , Ganjali , MR . A high performance method for thermodynamic study on the binding of human serum albumin with erbium chloride . J Therm Anal Calorim . 2009 ; 96 : 663 – 668

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The results of comparative thermodynamic study of GaSb-Sn system are presented in this paper. Calorimetric measurements according to Oelsen's method and EMF measurements with zirconia as solid electrolyte were used for experimental investigation, while Chou's general solution model, Toop, Kohler and Muggianu methods were used for predicting thermodynamic characteristics in this system. Also, phase diagram of this quasibinary system, determined by DTA and optical microscopy, is presented.

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Enzyme Inhibit Med Chem 21 : 537 – 542 10.1080/14756360600720903 . 12. Rezaei Behbehani , G 2009 A high performance method for thermodynamic study on the binding of

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Non-isothermal dehydration of copper chloride dihydrate and nickel chloride hexahydrate were studied by using TG, DTG, DTA and DSC measurements. The copper chloride salt loses its two water molecules in one step while nickel chloride salt dehydrates in three consecutive steps. The first two steps involve the loss of 4 water molecules in two overlapped steps while the third step involves the dehydration of the dihydrate salt to give the anhydrous NiCl2. Activation energies (ΔE) and the frequency factor (A) were calculated from DTG and DTA results. We have also calculated the different thermodynamic parameters, e.g. enthalpy change (ΔH), heat capacity (C p) and the entropy change (ΔS) from DSC measurements for both reactants. The isothermal rehydration of the completely dehydrated salts was studied in air and under saturated vapour pressure of water. Anhydrous nickel chloride was found to rehydrate in three consecutive steps while the copper salt rehydrated in one step.

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A thermodynamic study of the influence of the thermal treatments (annealing), below the glass transition temperature, on the thermal behavior and enthalpy of maltitol glass was carried out by differential scanning calorimetry (DSC). An enthalpic effect (exothermal) produced by the isothermal treatment of the quenched glass was found and measured. The origin of the thermal effect was assigned to a physicochemical transformation of molecular associations in the solid (glass). To achieve a correct description of the thermodynamic functions of glasses, another parameter, in addition to T and P, is introduced, namely the degree of advance of the above mentioned transformation.

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A thermodynamic study on the interaction of bovine carbonic anhydrase II (CAII) with nickel ions was performed by using isothermal titration calorimetry (ITC) at 27 °C in Tris buffer solution at pH = 7.5. The enthalpies of Ni2+ + CAII interaction are reported and analysed in terms of the new solvation theory. It was indicated that there are three identical and non-cooperative sites for Ni2+. The binding of a nickle ion is exothermic with dissociation equilibrium constants of 81.306 and 99.126 μM at 27°C and 37°C, respectively. The binding of nickel ions can cause some changes in the stability of the enzyme at low and high Ni2+ concentrations.

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Summary

The urobilinogenic chlorophyll catabolites are secondary metabolites formed by the biodegradation of chlorophylls. The thermodynamic study of the urobilinogenic chlorophyll catabolites from autumnal leaves extract of Parrotia persica and Hamamelis virginiana was done using reversed-phase liquid chromatography on the C4 and C8 analytical columns with acidified water-methanol mobile phase in combination with ultraviolet detection and electrospray ionization mass spectrometry. The presence of the urobilinogenic chlorophyll catabolites was detected by their characteristic ultraviolet absorption and their molecular mass. The retention behaviors of the two urobilinogenic chlorophyll catabolite isomers over a temperature range of 278–318 K were investigated. The retention time data permitted the construction of the van't Hoff plots. The stationary phase composition influences the thermodynamics of the retention of the urobilinogenic chlorophyll catabolites. The study presented can find the application in the separation of the urobilinogenic chlorophyll catabolites in autumnal leaves extracts.

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.1999.0540 . 4. Monte , MJS , Hillesheim , DM . Thermodynamic study on the sublimation of six substituted quinoxalines . J Chem Eng Data 2000 45 : 1088 – 1092 10.1021/je0001577

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product at 350 °C (aging time over 8 h) ( b ) Kinetic and thermodynamic studies from DSC data The maximum peak temperature of DSC curves at various heating rates was used to determine

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Thermodynamic studies of (LixK1−x)2SO4, LKS, mixed crystals have been made in the concentration range (x=0.1, 0.2, ...,x=0.5). The thermal behaviour has been investigated by differential thermal analysis, DTA, and differential scanning calorimeter, DSC, in the vicinity of high temperature phases. Also, the effect of the thermal neutron irradiations on the thermal properties of mixed crystals was studied. The results showed a change in the transition temperatureT c, as well as the value of specific heatC p at transition temperature, due to the change of stoichiometric ratio and radiation doses. The change of enthalpy and entropy of mixed crystals have been estimated numerically.

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