Arrhenius coordinates

Data for temperature coefficients (activation energies) given in Table 2 show one common phenomenon when plotting chemiluminescence intensity vs. temperature in Arrhenius coordinates, namely, that in the higher temperature range the activation energy is usually higher than at lower temperatures, which is... 

Table 8.4. Derivation of the Arrhenius coordinates for the 37Ar outgassing of the 15415 lunar...

Figure 5. Ratios of optical densities at 1730 cm 1/1705 cm1 plotted in Arrhenius coordinates for pure acrylic acid (100) and acrylic acid solutions in toluene at 90, 80, and 60 volume per cent of monomer (5).

The temperature dependence of radical generation rate in the Arrhenius coordinates at... 

At the initial period of mechanical destruction in a polypropylene melt in inert atmosphere the concentration of macromolecules increases (figure 2). The dependence of destruction rate (V ) on temperature is linear in the Arrhenius coordinates. After a certain... 

Table 11.3 Heat release rate as a function of temperature in Arrhenius coordinates.

The long time limit was chosen to be the time where the transient absorption reaches a maximum.) We observe three relaxation processes (i.e., N — 3). The kinetic phases are well separated in time, spanning hundreds of nanoseconds to hunderds of microseconds. The amplitudes contribute more or less equally to the total decay, the slowest phase contributing the least. What is particularly interesting, however, is that the relaxation times for the 1620 cm-1 data are faster than those at 1661 cm-1. This is easily seen in Fig. 17.7 where the observed rate constants (1/t = kohs — kF + ku) for each phase are plotted in Arrhenius coordinates (i.e., In feobs vs. 1/T). The activation enthalpy ATP can then be determined from the slope according to... 

Table 7.3 shows values of effective rate constants for different temperatures. Table data indicate that the epoxidation rate (7.8) is low compared with the complex formation rate (ki/k2) 102-103). If we plot keS values in Arrhenius coordinates, the numerical value of effective activation energy for propylene epoxidation is determined 8.76kcal/mol corresponding to enzymatic processes (7-15kcal/mol). 

The amounts of the reacted CO molecules and formed C02 molecules were monitored by volumometry. They proved to be close to each other. The SG => SC was monitored optically (cf Sections 9.4 and 9.6) by recording changes in the band intensities of these centers at 5.65 and 5.3 eV, respectively (in this case, the sample was cooled to 300 K). The rate constants for the reactions were derived from the kinetic curves of the CO molecules consumed at various temperatures. The temperature dependence of the rate constant for this reaction is shown in Figure 7.3a, in the Arrhenius coordinates. The activation energy for the process was found to be 20.7kcal/mol. Similar method was used to measure the rate constant for the reverse reaction ... 

Figure 3.18. Data on the correlation frequency of the mobility of physical labels and their environment in bovine and human serum albumins and in the photosynthetic RC (I) and the rate constants of ET s primary donor (P) to the bacteriaophephytin acceptor (II) in the Arrhenius coordinates. (Likhtenshein, 1996). Reproduced with permission.

Figure 3. Temperature dependence in Arrhenius coordinates) of polymer chain growth time T (curve 1) and mean time of one unit attachment to this chain Tq (curve 2) under radiation-induced polymerization of formaldehyde.

Fig. 1. Viscosity-temperature relationship in Arrhenius coordinates. Curve numbers correspond to liquid numbers of Table 3.

The conductivity of the crystal in Arrhenius coordinates is represented by a straight line, and the activation energy is evaluated from the conductivity plot as a function of temperature, a 46 kJ/mol [193]. The activation energy, assessed from broadening of the PMR band in accordance with the Waugh-Fedin relation, proved to be equal to a2 33.1 kJ/mol [193,202]. Investigation of... 

Comparison of Eqs. (11-70) and (11-68) indicates that the apparent activation energy determined from Eq. (11-70) would be one-half the true value, E. The measured rate, when plotted in Arrhenius coordinates, would appear as in Fig. 11-9. At low enough temperatures the data would determine a line with a slope equal to —EJRg, because rj would approach unity. However, at high enough temperatures intrapellet diffusion would be important Eq. (11-68) would be applicable, and a line with a slope of — EJRg would result. These conclusions would be the same regardless of the reaction order. 

Transformation rates are plotted versus temperature in ARRHENIUS coordinates in Fig. 26. Two straight lines appear from which it can be assumed that the ARRHENIUS LAW is fulfilled and the apparent activation energies calculated from their slopes. 

Effect of metal loading (samples 1-5). In this series of catalysts was varied by two orders of magnitude our findings allowed us to determine the initial rates of exchange r over a wide range of metal areas. The results are plotted in Arrhenius coordinates in Fig.3. For this series of catalysts,... 

Results of measurement of electroconductance vs. temperature in air for synthesized OIL ceramics, pure and doped with CaO and Hf02, are presented at fig. 1-3 accordingly. In Arrhenius coordinates Ig p - 1/T in temperature range 1000 - 1600 °C these results can be approximated by a straight lines or consist of 2 straight-line parts, which declinations were used to calculate the activation energies of electrical conductivity, listed in the table. 

The values of E obtained by Eq. (46) depend essentially on Tmax- For the determination of the activation energies, Martin and Duprez directly used the beginning of the curves of the exchange by plotting the values of x at different temperatures (T < Tmax) in Arrhenius coordinates. The values of E obtained by this procedure are more dependent on the shape of the curves at low temperatures, than on the position of the rate maximum. 

The presentation of values into Arrhenius" coordinates equation Figs. 6 and 11 permitted to obtain the expressions for concentrated solutions and... 

A maximum in the Arrhenius coordinates follows from the fact that the two terms in eq. [13.1.28] depend differently on temperature. Density fluctuation around the reacting pair is determined mainly by the entropy of repacking hard spheres representing the repulsive part of the intermolecular interaction. Mathematically, the entropy of activation arises... 

Fig. 4.9 Temperature dependence ofthe parameter to, min (Fig. 4.8) of Eq. (4.3) in Arrhenius coordinates...

Interpretation of the experimental values of the P parameter obtained at different temperatures in Arrhenius coordinates is presented in Figure 7.16. The respective linear regression equations used for calculation of the activation energy of the monomolecular chain termination are also presented in Rgure 7.16 and in Table 7.6 (f ). 

The dependencies obtained in the Arrhenius coordinates and respective regression equations are represented in Figure 7.17. 

Figure 7.17. Dependence of the viscosity on temperature in the Arrhenius coordinates for DMEG, OCM-2 and MGPh-9.

The presentation of values Tm into Arrhenius coordinate s equation (Figure 4) permitted to obtain the equation ... 

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