Percent hysteresis

The hysteresis behavior of the HIBI series is shown in Figure 13B. All of the samples have much higher hysteresis than the corresponding member (with respect to composition) of the HBIB series. Although there is a noticeable decrease in the percent hysteresis with an increase in rubbery HI content, the hysteresis does not fall below 55% at high extensions. 

The mechanical hysteresis of poly ether PUs investigated by Gorge et al was studied as a function of temperature, percent strain, and deformation energy. Hysteresis values remained small at low temperatures when the extent of the sample deformation did not disrupt the glassy matrix. This was readily evident at temperatures below the glass transition temperature Tg) of the polymer where the material did not formally yield. At temperatures above the Tg of the polymer, hysteresis remained small even at substantial strains levels and demonstrated the capabilities of the HS domains to act as physical crosslinks. At high emperatures, the percent hysteresis increased as the hydrogen-bonded HS domains weakened. 

Enantiomeric discrimination and its relation to film component reorganization upon compression can also be observed in dynamic surface tension hysteresis loops. Figure 26 shows the WjA isotherms generated upon five successive compression/expansion cycles (from II = 0 to lOdyncm-1) of racemic and enantiomeric films containing 17 mole percent palmitic acid. The hysteresis loops, obtained on the apparatus described in Section 2 (p. 63), show that the first compression/expansion cycle of the racemic system is repeated in each successive cycle. Upon expansion of the film from the maximum surface pressure back to Odyncm-1, the racemic film returns to its original state without detectable reorganization of the components. However, the... 

Figure 9. Hysteresis loops of FePt/C samples with particle size of 3 nm and carbon vol% of A) 66.7 B) 58.3 C) 50.0 and D) 37.5 percent.

Because pressure transducers from different manufacturers can vary significantly, it is important to understand their performances such as accuracy. An ideal device would have a direct linear relationship between pressure and output voltage. In reality, there will always be some deviations this is referred to as nonlinearly. The best straight line is fitted to the nonlinear curve. The deviation is quoted in their specifications and expressed as a percent of full scale. The nonlinear calibration curve is determined in ascending direction from zero to full rating. This pressure will be slightly different from the pressure measured in descending mode. This difference is termed hysteresis it can be reduced via electrical circuits. 

This hysteresis effect was studied by Orr and his colleagues (1958a), who found that solution takes place over a range of 68 to 80 percent relative humidity for various inorganic salts, while recrystallization does not occur until relative humidities are about 30 percent lower. 

So, in conclusion the present state of the theory is that x = 0(10" -10 N). Hence the action of the line tensions can only be observed for drops substantially below the 1 p cross-section remge. For instance, let in (5.6.1) r = 1 p, y= 0(10 mV m ), it follows that r/r = 0(10" N m" ), which is less than a percent of cos a. This is below the usual sensitivity of the measurements cmd mueh less than the uncertainty caused by hysteresis. The implication is that for most practical purposes the effect of line tension is eclipsed, or at least it becomes cin esoteric quantity. 

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