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Abstract  

At a given surfactant-surfactant ratio, the enthalpies of transfer ΔH (W→W+S) of pentanol 0.03m from water to sodium dodecylsulfate (NaDS)-dodecyldimethylamine oxide-water mixtures as functions of the surfactants mixture concentration (m t) were determined. ForX NaDS=0.9, ΔH (W→W+S) increases monotonically withm t such as observed for pure surfactants. ForX NaDS=0.12 and 0.3, ΔH (W→W+S) increases withm t up to 0.12m beyond which it decreases withm t. AtX NaDS=0.6, two monotonic curves can be distinguished in the ΔH (W→W+S)vs. m t trend. Experimental data were fitted through an equation previously reported for additives in pure surfactants derived by assuming the pseudo-phase transition model for the micellization and a mass action model for the distribution of the additive between the aqueous and the micellar phases. This method did permit to simultaneously obtain the distribution constant of the alcohol between the aqueous and the micellar phase (and, then, the standard free energy of transfer) and its enthalpy of transfer from the aqueous to the micellar phases. By combining these properties the standard entropies of transfer were calculated. From these results, the excess properties of pentanol in the mixed micelles were calculated as a function of the mixture composition. The excess enthalpies and entropies are positive and compensate with each other leading to null values for the excess free energies in the whole range of the mixed micelles composition.

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monotonically decreasing, the increase to 45° makes ϕ to have non-monotonic behavior, changing from crescent below 500 mbar to decrescent above 500 mbar. Finally, at 90° the behavior is strictly crescent. Fig. 5 (Color

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continuity of the thermodesorption process and monotonic changes of adsorption layer properties depends on the distance of liquid molecules from the surface. A few distinct peaks of water indicate the presence of water molecules on the surface in different

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. Saffarini [ 19 ], in his study on Se 100− x In x chalcogenides concluded that the TS of the quenched glasses decreases monotonically with increasing the In-content up to x = 29 at.% In. In contrast to this conclusion, Imran et al. [ 20 ] reported a

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completed (TG u plots end at the same level corresponding to V 2 O 5 ). At the higher sample heating rates passage to this level in not monotonic. This is connected with oxidation of V 2 O 5− x formed earlier (e.g., for β = 6 K/min; x = 0.02). At the

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. The average micro-strain (∊) was also obtained. It was found that ∊ increases monotonically with the milling time. The increasing in ∊ results mostly from plastic deformations introduced by mechanical collision between the grinding elements (balls and

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annealing, the jump monotonically increased, which testified to the lithium pentaferrite phase accumulation at 600 °C in the examined range of annealing times. Third, an endothermic peak arose and increased on the DSC curves at ca. 753 °C caused by

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Journal of Thermal Analysis and Calorimetry
Authors: Zs. Baji, Z. Lábadi, Z. E. Horváth, M. Fried, B. Szentpáli, and I. Bársony

two orders of magnitude at the most by Al doping. Between 100 and 200 °C growth temperature, the resistivity of intrinsic ZnO decreases monotonically. Surprisingly, in this range both the electron mobility and the carrier concentration decrease

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is observed around (above and below) the ulceration, in what may be connected to an inflammatory state, and swelling changes around the ulceration—AR02. After hyperbaric oxygenation, the temperature changes become more monotonic. Studies

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change decreases monotonically in most cases, as shown in Fig. 5a . However, variation is high for the sample having the composition KNO 3 :Al:S with 68:8:24, because of very low fuel content. The variations may be due to the inhomogeneous mixing and the

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