Characteristic values of bursting

Table 19 Characteristic values of bursting charges for chrysanthemums...

The characteristic values of the above bursting charge are shown in table 19. As we see in the table, the starting velocity of stars propelled by KP can be increased to the same value as H3 by increasing the number of pasted layers of paper to 1.2 times more than is required for H3. 

Crossover value The crossover value is a characteristic quantity of an already cold refrigerator cryopump. It is of significance when the pump is connected to a vacuum chamber via an HV / UHV valve. The crossover value is that quantity of gas with respect to T =293 K which the vacuum chamber may maximally contain so that the temperature of the cryopanels does not increase above 20 K due to the gas burst when opening the valve. The crossover value is usually slated as a pV value in in mbar I. 

As indicated by the above bifurcation diagrams, the three-variable system (6.3) is capable of displaying different modes of simple or complex oscillatory behaviour. One additional mode is that of birhythmicity for certain values of the parameters, eqns (6.3) admit a coexistence between two simultaneously stable periodic regimes. In the phase plane (pr, a, y), these two regimes correspond to two limit cycles, one of which possesses a smaller amplitude and the second the folded appearance characteristic of bursting (fig. 6.6). 

Hence, counterion localization occurs when the number of generations in the star-burst polymer, g log2(Af/n), reaches some characteristic value, which is controlled by the same combination of the parameters, as for a PE star. 

With the initial conditions of ds/dt = 0 at t = 0 and s = So at t = 0, Eq. 23 can be numerically solved to yield the displacement and velocity characteristics of the advancing capillary meniscus. Since the effect of added mass is not incorporated in Eq. 22, a nonzero value of sq is required to avoid the prediction of an unrealistic initial burst at t = 0, as explained earlier. One major cmiclusimi that can be drawn from the numerical simulatimi studies of Yang et al. [8] is, based on the above model, that while liquid slip on hydrophobic surfaces may increase the flow velocity, the presence of a capillary pressure across the liquid—vapor interface can suppress the electroosmotic flow and significantly decrease the flow performance. 

Tables 4—6 Ust ASTM methods used for the characterization of PB and PMP. A number of specialized methods were developed for testing particular articles manufactured from polyolefins several of these determine the performance of PB and PMP film, including the measurement of the film s dart impact strength and tear strength. Dart impact strength is measured by dropping a heavy dart with a round tip on a stretched film. Tear resistance, which reflects the film s resistance to tear propagation, is measured with the Ehnendorf tear tester. Two values for the tear strength are usually reported, one in the machine dkection of the film and the other in the transverse dkection. Pipes manufactured from PB are tested by pressurizing them internally with water the time-to-burst failure is determined at various temperatures (46). The standard test method for haze and luminous transmittance (ASTM D1003) is used for the measurement of PMP optical characteristics.

All of the papermaking properties showed deterioration as a result of the exposure to the temperatures of the kraft cycle. The tensile strength was reduced by 20%, the burst properties declined by 30%, and the tear properties, by approximately 45%. A test of the absorbency of the fibers indicated that the water retention characteristic of the fibers had declined to 60% of its original value after the heat treatment. All of the changes observed as a result of the exposure to elevated temperatures reflect an increase in the level of crystallinity of the pulp fibers. 

---