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Summary Proton concentration in SrZr0.95M0.05O3-α (M=Ga, Sc, Y and Nd) was measured with a thermobalance at different temperatures (T=673-973 K) and water vapor pressures (P H2O=0.9-12.8 kPa). At all the pressures and temperatures examined, the amount of proton concentration in these samples is in the order of Sc>Y>Ga>Nd. By an equilibrium evaluation, we estimated the maximum possible proton concentration about 2.0 mol% in these samples. Infrared (IR) absorption spectra are measured in these samples. The absorption bands can be fitted by four (M=Ga, Y, Nd) or three (M=Sc) Gaussian bands.

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The degradation process of fructo-oligosaccharides (Raftilose® P95) has been studied in apple pulp matrix at 70–80 °C in pH range 2.7–3.3. Changes of sugar compositions have been analysed by an appropriate isocratic HPLC with differential refractive index detector for oligosaccharide determination. According to Arrhenius equation significant effect of temperature has been observed on the decrease of oligomer concentration. The oligomers (DP3-DP7) degrade continuously at any pH between 2.7 and 3.3. The lower the pH the higher the change of oligomer and monomer concentration is. The oligomers (DP4-DP7) could give out in 30–40 min below pH 3.0 caused by the high concentration of protons. The rate of degradation depends not only on the processing time, temperature, and the proton concentration of the solution, but on the characteristic of apple pulp, too, where the degradation is significantly higher than that in water solution.

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Dependence of k obs on the proton concentration at three different concentrations of HU. Conditions: [VO 2 + ] = 0.5 mM, I = 2.0 M, θ = 25 °C, [HU] = 5 mM ( bottom curve ), 20 mM ( middle curve ) and 100 mM ( top curve ). Data were fitted according to

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Reaction Kinetics, Mechanisms and Catalysis
Authors: F. J. Lona-Ramírez, R. Herrera-Muñoz, V. Rico-Ramírez, F. Louvier Hernández, G. Luna-Bárcenas, and G. González-Alatorre

). The first order dependence with respect to each of the reagents in the nitrosation of TMU were consistent with those found for the nitrosation of the substituted mono and diureas [ 13 ]. The influence of acidity on k was studied over the proton

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density at the metal oxide surfaces. The lower ionic potential ( q / r ) of ZnO (∼2.7) compared to Al 2 O 3 (∼5.6) arises from the high proton concentration at the oxide surface and leads to increased interaction with both carbonyl and carboxylate ionic

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respiration of these microalgae have a close resemblance with those in plants and thus they are valid models for them. As is known, infringement of an ionic homeostasis as in a case of salting, and any ion stress, including changes of proton

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. 18. Brandariz , I , Barriada , J , Vilarino , T , de Vicente , MS . Comparison of several calibration procedures for glass electrodes in proton concentration . Monatsh Chem . 2004 ; 135 : 1475 – 1488 . 10.1007/s

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