Effect of temperature on degradation

Because of the E/CO s rapid loss of physical properties from ultraviolet radiation, it is critical that resin, and, especially, articles made from the copolymer be protected from direct exposure to light sources as long as possible prior to the time that deterioration is desired. 

The presence of condensation on the surface of E/CO may influence the rate of degradation. Studies performed utilizing the condensation mode with the Q-U-V apparatus showed E/CO exposed to both UV and condensation to have a slower rate of degradation than a similar sample exposed solely to UV [17]. 

Q-U-V cycle was 20 h light followed by 4 h condensation E/CO copolymer CO content -1 0 wt.% 

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The effect of temperature on degradation during potential cycles between 0.87 and 1.2 V was investigated by Bi and Fuller [68]. Experiments were conducted... 

Finally, the effect of temperature on the life of anion exchange resins must be considered. Many of these materials are sensitive to high temperatures, and degradation of the resin may result if process tem-... 

The effect of temperature on the rate of degradation can be seen by inspecting the degradation plots in Figures 5 and 13 where Weedone and Treflan had been respiked. The respiking... 

Trevors, J.T. (1982). Effect of temperature on the degradation of pentachlorophenol by Pseudomonas species. Chemosphere, 11, 471-5. 

Hamid, I.A. and Parrott, E.L (1971). Effect of temperature on solubilization and hydrolytic degradation of solubilized benzocaine and homatropidepharm. Sci, 60, 901-906. 

Using the information provided in Tables 1 and 2, it is straightforward to calculate the effect of temperature on the degradation rate to enable... 

The concentration of volatile compounds in the cavitation bubbles increases with temperature thus, faster degradation rates are observed at higher temperatures for those compounds [23]. Conversely, in the case of nonvolatile substrates (that react through radicals reactions in solution), the effect of temperature is somehow opposed to the chemical common sense. In these cases, an increase in the ambient reaction temperature results in an overall decrease in the sonochemical reaction rates [24]. The major effect of temperature on the cavitation phenomenon is achieved through the vapor pressure of the solvent. The presence of water vapor inside the cavity, although essential to the sonochemical phenomenon, reduces the amount of energy... 

Fig. 9. Effect of irradiation on degradation of albumin as the function of irradiation temperature and dose...

Figure 11, the effect of temperature on color degradation, also reveals that the color degradation is strongly controlled by the diffusivity of the reactants. The apparent activation energy of used catalyst was 3/4 of that of fresh catalyst. 

Table 19.9 Effect of temperature on LDPE degradation (screw speed of 11 rpm) [11]. (Repro- ...

It is worthwhile to consider in more detail the effect of lamp intensity on the rate of photodegradation (k ) and the effect of temperature on the rate of thermal degradation (k and k ) in order to better understand the implications of these two important variables. In general, it can be expected that... 

Table 1 Effect of Temperature on Thennal Degradation Rate (k ) (Assuming Arrhenius Kinetics)...

Zhao, Y. et al., Highly enhanced degradation of dye with well-dispersed TiO, nanoparticles under visible irradiation, J. Alloys Compounds, 440, 281, 2007. Akratopulu, K.C., Kordulis, Ch., and Lycourghiotis, A., Effect of temperature on the point of zero charge and surface charge of TiOj, J. Chem. Soc. Faraday Trans., 86, 3437, 1990. 

Fig. 4.12a. Effect of temperature on the stability of o,p -DDT in animal feed BCR-CRM 115. The dotted line ( ) represents the ratio and combined uncertainty (vertical line) of each of three measurement results (performed at 1,3, 6 and 12 months) and obtained at +20 °C versus -20 C. Ratios of measurements at +37 °C (+) show a rapid decrease of o,p -DDT. An inverse picture could be found when monitoring o,p -TDE which is the degradation product of DDT. DDT was considered to be stable at +20 C. Definitions of R and U are given in the text.

A general equation analogous to the Arrhenius and Eyring equations for the effect of temperature on chemical degradation has not been developed to describe the effect of humidity. A linear relationship between the logarithm of the rate constant (or a constant... 

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