the charge-transfer complexation reaction between iodine and dibenzo- 18-crown- 6 (db18c6) has been studied spectrophotometrically in chloroform solution at different temperatures. the resulting donor-acceptor complex was formulated as (db 18c6…i )i . the spectrophotometric results , as well as the conductivity measurements, indicated that the gradual release of tiiodide ion from its contact io...

the relationship between the randic , wiener, hosoya , balaban, schultz indices, harary numbers anddistance matrix to enthalpies of formation (airf), heat capacity, (cp) , enthalpies of combustion (ah °c ),enthalpy of vaporization (ah °vap) and normal boiling points (bpk)of c2 c10 normal alkanes isrepresented

The enthalpy and volume changes, deltaH and deltaV, associated with the 266 nm laser-induced photoionization reactions of aqueous ferrocyanide and iodide ions, to yield the hydrated electron, e(-)aq, and oxidized products were determined by temperature-dependent time-resolved photoacoustics. The photoionization quantum yield as function of temperature (9-30 degrees C) was determined by laser fl...

The charge-transfer complexation reaction between iodine and dibenzo- 18-crown- 6 (DB18C6) has been studied spectrophotometrically in chloroform solution at different temperatures. The resulting donor-acceptor complex was formulated as (DB 18C6…I )I . The spectrophotometric results , as well as the conductivity measurements, indicated that the gradual release of tiiodide ion from its contac...

The standard molar enthalpy of formation of the ionic liquid 1-butyl-1-methylpyrrolidinium dicyanamide has been determined at 298 K by means of combustion calorimetry, while the enthalpy of vaporization and the mass spectrum of the vapor (ion pairs) have been determined by temperature-programmed desorption and line of sight mass spectrometry. Ab initio calculations for 1-butyl-1-methylpyrrolidi...

We report a combined thermodynamic and structural characterization of a DNA tetraplex. Using spectroscopic and calorimetric techniques, we demonstrate that d(TG3T) and d(TG3T2G3T), in the presence of K+, form stable tetramolecular complexes. From differential scanning calorimetry measurements, we obtain the following thermodynamic profiles for formation of each tetraplex at 25 degrees C: delta ...

We derive exact expressions for the local entanglement entropy epsilon in the ground state of the one-dimensional Hubbard model at a quantum phase transition driven by a change in magnetic field h or chemical potential mu. The leading divergences of delta epsilon/delta h and delta epsilon/delta mu are shown to be directly related to those of the zero-temperature spin and charge susceptibilities...

Thermal unfolding curves have been measured for a series of short alanine-based peptides that contain repeating sequences and varying chain lengths. Standard helix-coil theory successfully fits the observed transition curves, even for these short peptides. The results provide values for sigma, the helix nucleation constant, delta H0, the enthalpy change on helix formation, and for s (0 degree C...

The aim of this work was to investigate bovine serum albumin (BSA) and cinnamic acid (CA) interaction at different pHs, by fluorescence spectroscopy. We found that BSA forms complex with CA at pH 3.5, 5.0 and 7.4. The binding constants (Kb) were 4.08 x 10 4 L.mol -1 , 2.44 x 10 4 L.mol -1 and 19.1 x 10 4 L.mol -1 for each cited pH, respectively, stoichiometry (n) was around 1 and the standard G...