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Abstract  

The extremely diluted solutions are anomalous solutions obtained through the iteration of two processes: a dilution 1:100 in mass and a succussion. The iteration is repeated until extreme dilutions are reached (less than 110-5mol kg-1) to the point that we may call the resulting solution an extremely diluted solution, namely the composition of the solution is identical to that of the solvent used (e.g. twice distilled water). We conducted thermodynamic and transport measurements of the solutions and of the interaction of those solutions with acids or bases. The purpose of this study is to obtain information about the influence of successive dilutions and succussions on the water structure of the solutions under study. We measured the heats of mixing of acid or basic solutions with such extremely diluted solutions, their electrical conductivity and pH, comparing with the analogous heats of mixing, electrical conductivity and pH of the solvent. We found some relevant exothermic excess heats of mixing, higher electrical conductivity and pH than those of the untreated solvent. The measurements show a good correlation between independent physico-chemical parameters. Care was taken to take into account the effect of chemical impurities deriving from the glass containers. Here we thus show that successive dilutions and succussions can permanently alter the physico-chemical properties of the water solvent. The nature of the phenomena here described still remains unexplained, nevertheless some significant experimental results were obtained.

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Cryogenic heat-capacity determinations provide a useful tool for the determination of the energetic spectrum of condensed phases and also reveal information on their discrete electronic level structures as well. We have been interested in applying these techniques to actinide elements and have in recent months been working up the techniques to unravel the corresponding data for the lanthanide compounds—where opposite trends in cationic masses and molar volumes provide an opportunity to test theories useful for the resolution of excess heat capacity from lattice contributions.

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. The repeated scan of denatured sample was used as baseline reference, which was subtracted from the original DSC curve. Simple mathematical calculations were used to obtain the thermodynamic data of samples (excess heat capacity C p,ex , transition

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composition, β = 0.72 and T 0 = 333 K [ 20 ]. The calculated values of T g are given in Table 1 . Table 1 The values of E g (by Kissinger), fragility ( F ), specific heat capacity ( C p ), excess heat

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in temperature between the crucibles will change in time. Excess heat flow to crucible S is 22 or 23 24 25 26 T R increases according to Eq. 25 because DSC cell is heated with constant heating rate β . T S

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Journal of Thermal Analysis and Calorimetry
Authors: G. Giannini, F. Cuppo, L. Fontanive, N. D'Amelio, A. Cesàro, A. Maiocchi, and F. Uggeri

Figure 5 shows heat of dilution data plotted against the concentration of iomeprol and reports data of iopamidol and iomeprol at 25 °C already calculated. The linearity of plot of Fig. 5 suggests that the excess heat of mixing ( h ij in the notation

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heating rate is increased. The excess heat absorbed in comparison with that at lower heating rates, causes the transformation (from glassy to rubbery state) to occur at a higher temperature. The variation of T gp with CdS weight percent is reproduced in

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apparent excess heat capacity ( C p ) of thermally unfolded protein is higher than that of the more compact folded conformation. This is illustrated in Fig. 1 , showing how the unfolding enthalpy (Δ H unf ), obtained from the area under the DSC transition

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a slight step at 219.64 K on the C p,m − T curve of Fig. 1 , and a sharp endothermic peak on the DSC curve ( Fig. 2 ) at 220.44 K. The combined consideration of the mechanism of the glass transition, the disappearance of the excess heat capacity

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) Temperature calibration and symmetry Sensor calibration Since the applied power compensation principle allows direct measurement of the excess heat flow, and by virtue of the small time constants of the XI-400 chip, a

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