Yield threshold

Table 3. Yield threshold and effective turgor pressure in growing tissues...

Cosgrove, D.J., Van Volkenburgh, E. Cleland, R.E. (1984). Stress relaxation of cell walls and the yield threshold for growth Demonstration and measurement by micropressure probe and psychrometer techniques. Planta, 162, 46-52. 

An important measurement is an accurate determination of the y-ray yield threshold for exciting a particular level. Thresholds can be determined with uncertainties of only a few keV, when necessary to guarantee certain placement of a y-ray in a level scheme. Usually, thresholds determined to within 30 to 50 keV are sufficient for this purpose, even in fairly heavy nuclei. The reason for this is that, typically, excited levels will have one or more decays to low-lying levels which are spaced 50 keV or more apart, even in heavy deformed nuclei. 

If measurement uncertainties can be assumed to be bounded, then application of the triangle inequality may yield thresholds for parameter variations of ARR residuals that are independent of measurement uncertainties. For instance, let z be the predicted part of an output variable z of the diagnostic bond graph that controls a modulated sink of the incremental bond and let Az < be the bounded measurement uncertainty. Furthermore, let Ar be the variation of an ARR residual r that depends on z and its derivative. Then... 

Stearic acid was successfully delivered to the human oral cavity by emulsions at 67-69 °C where this stimulus is in liquid form [4, 22]. Detection thresholds were identified by orthonasal olfaction, retronasal olfaction, gustation, and a multimodal presentation where the lipid emulsion was placed in the oral cavity in the absence of nose clips [4]. Although measured at different temperatures, intensity responses for stearic acid were similar to the 18-carbon cis- unsaturated fatty acids linoleic and oleic acid. Oral detection thresholds for stearic acid in the human oral cavity with emulsions, yielded thresholds near 0.032% (w/v) [4, 22]. In addition, most study participants were able to detect stearic acid in the oral cavity [4,22]. 

Kinetic resolutions catalyzed by BVMOs are usually limited to the theoretical 50% yield threshold. In 2002 a dynamic protocol mediated by base-catalyzed... 

At low energies the abstraction process dominates and at higher energies the exchange mechanism becomes more important. The cross-sections for the two processes crossing at 10 eV. The END calculations yield absolute cross-sections that show the same trend as the experimentally determined relative cross-sections for the two processes. The theory predicts that a substantial fraction of the abstraction product NHjD, which are excited above the dissociation threshold for an N—H bond actually dissociates to NH2D" + H or NH3 during the almost 50-ps travel from the collision chamber to the detector, and thus affects the measured relative cross-sections of the two processes. 

Pseudoplastic fluids have no yield stress threshold and in these fluids the ratio of shear stress to the rate of shear generally falls continuously and rapidly with increase in the shear rate. Very low and very high shear regions are the exceptions, where the flow curve is almost horizontal (Figure 1.1). 

Fig. 7. Toxicity of chlorine to aquatic organisms, (a) Time-dependent mortaUty (50%) of four example species in various levels of total residual chlorine in the laboratory, where for A, A.losa aestivalis and B, Salmogairdnerii r (correlation coefficient of the curve) = —0.96 and for C, P/euroneetesplatessa and D, Salmo trutta r = —0.98. (b) A summary of chlorine toxicity to freshwater species, indicating overall no-effect thresholds for acute and chronic exposures. Numbers indicate where more than one test yielded the same result. A different summary figure appHes to marine organisms because of differences in the...

Sufficient tensile stress. Sufficiency here is difficult to define since it depends on a number of factors such as alloy composition, concentration of corrodent, and temperature. In some cases, stresses near the jdeld strength of the metal are necessary. In other cases, the stresses can be much lower. However, for each combination of environment and alloy system, there appears to be a threshold stress below which SCC will not occur. Threshold stresses can vary from 10 to 70% of yield strength depending on the alloy and environment combination and temperature (Fig. 9.6). 

Figure 7.6 shows the relationship between the meehanieal threshold and the separation between pinning points for dislocation segments. The mechanical yield strength is controlled by the largest separation, Hence, behind... 

None of the foregoing methods will tell the frequency or duration of exposure of any receptor to irritant or odorous gases when each such exposure may exceed the irritation or odor response threshold for only minutes or seconds. The only way that such an exposure can be measured instrumentally is by an essentially continuous monitoring instrument, the record from which will yield not only this kind of information but also all the information required to assess hourly, daUy, monthly, and annual phenomena. Continuous monitoring techniques may be used at a particular location or involve remote sensing techniques. 

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