Allowable stresses, factors influencing

As with materials of construction correction factors, the pressure correction factors in Table 2.5 are average and only approximate and will vary, amongst other things, according to the type of equipment. Finally, its operating temperature also influences equipment capital cost. This is caused by, amongst other factors, a decrease in the allowable stress for materials of construction as the temperature increases. Table 2.6 presents typical factors to account for the operating temperature. 

In summarizing the current knowledge on host factors, it must be stressed that only limited and insufficient data are available on how host factors influence LADME and thus bioavailability of phytochemicals. It is unclear to what extent and how such parameters should be considered. From the perspective of the efficacy and risk assessment, more knowledge is certainly needed to allow identi-fication of subpopulations at particular risk, who would benefit from appropriate dietary advice or treatment. 

In this paper we use a mechanical model to study the behavior the interstitial flows in cortical bone tissues under cyclic loading. The proposed model allows investigating the influence of different factors like strain rate, load s frequency, permeability and possibly presence of a microcrack on the interstitial fluid velocity which strictly related to shear stress acting on osteon cells. 

In conclusion we should stress that quantification of rates of redox reactions in natural systems is difficult. Numerous compound- and system-specific factors may influence the overall reaction rate. Evaluation of the relative reactivities of a series of structurally related compounds that are likely to react by the same reaction mechanism(s), may, however, provide important insight into the processes determining a given reaction in a given system. Such information may allow at least order-of-magnitude estimates of how fast a given compound will undergo oxidation or reduction in that system. 

When evaluating the influence of the time of year on responses of aquatic communities to chemical stress, it is convenient to make a distinction in threshold concentrations of direct toxic effects, and in the magnitude of effects that occur above these threshold concentrations. Only a limited number of (model) ecosystem experiments are available that allow a comparison of responses due to treatment with the same chemical in the same type of test system at different periods of the year. These studies indicate that, in freshwater communities, threshold concentrations for direct toxic effects may vary little with the season (within a factor of 2). At higher exposure concentrations, however, the intensity and duration of the responses (direct and indirect effects) may vary considerably between different periods of the year (Section 6.3.2). 

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