KJ/mol S =5167 J/(K mol)SDa typical deviation of slope

KJ/mol S =5167 J/(K mol)SDa typical deviation of slope regression, SDb common deviation of worth b, r coefficient of linear correlation a Value was calculated from Arrhenius equation; for RH 76.four lnki =(-12,550,827)1/T [K])+(22) and for RH 0 lnki =(-18,4173,463)1/T [K])+(35)Table IV. The Impact of Humidity around the Stability of IMD in Solid State at 90 RH 25.0 50.9 60.six 66.five 76.4 106 k [s-1] 0.827.046 2.20.16 two.81.20 3.23.22 four.88.41 -r 0.997 0.996 0.996 0.995 0.995 n 10 10 ten 10Regulska et al.Parameters of regression ln ki =f (RH ) a =0.0338.0050 SDa =0.0016 b =-14.82.29 SDb =0.091 r=0.a slope of regression ln ki =a(RH )+b, SDa standard deviation of slope regression, SDb common deviation of value b, r coefficient of linear correlationshape with three distinct reaction phases, which includes an initial slow phase followed by a fast phase, which finally led the reaction to its completion. This appears analogous to the threephase autocatalytic reaction model distinguished by its initiation, acceleration, and termination period in which the formed degradation item acts as a reaction catalyst and its formation accelerates the reaction price. Hence, to confirm our assumptions, the mathematical model fitting was performed, and certainly, the observed experimental data have been identified to become a great match towards the theoretical autocatalytic model at all temperatures (r0.991), described by a Prout ompkins relationship (17): ln ct = 0 -ct C-kt where c0 and ct represent concentration of IMD at time points 0 and t, C is induction period, and k stands for degradation rate constant (second-1). The least squares method was employed to calculate the regression parameters y=ax+b, a , and b b, regular errors Sa, Sb, and Sy, along with the correlation coefficient r. The and were estimated for f=n-2 degrees of freedom and =0.05. It’s crucial to emphasize that only the points attributed to the acceleration period had been deemed within the mathematical interpretation of our experimental circumstances. For this reason, it may be frequently stated that below the applied analytical conditions, the method of IMD decay follows the autocatalytic reaction kinetics, which is characterized by two parameters, i.e., length with the induction period and also the reaction rate continual calculated forthe data obtained for the acceleration phase. The length from the induction period was demonstrated graphically and its gradual reduction using the increase of temperature was observed, indicating that the decreasing IMD stability correlates using the elevation of this parameter (Fig. 2). Moreover, the linear, semilogarithmic plots, obtained by the application of ProutTompkins equation enabled the calculation of the reaction rate constants (k) which correspond to the slope of the analyzed function (Fig.PS48 3).Pindolol The escalating values of k further confirm that with the increase of temperature, the stability of IMD declines.PMID:24377291 Table III summarizes the price constants, halflives, and correlation coefficients obtained for every single investigated temperature condition. It is also worth mentioning that in our further research, in which we identified two degradation merchandise formed in the course of IMD decay under humid environment, the detailed evaluation of their formation kinetics was performed. We evidenced that both impurities, referred as DKP and imidaprilat, have been formed simultaneously, as outlined by the parallel reaction, and their calculated formation price constants had been not statistically unique. Moreover, their.