Final causes

Pitting had two distinct causes. Sulfate reducers had formed the large hemispherical pits. The more undercut pits were formed during a low-pH excursion involving mineral acid after the sulfate-reducing bacteria became inactive. It is likely the low-pH excursion deepened preexisting sulfate-reducer pits, causing final perforation. 

The cause finally was traced to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), which is produced as an impurity in the manufacture of 2,4,5-T. 

The man was engaged for two and a half years in the preparation of hypophosphites his illness commenced with spots before the eyes, and inability to fix the attention. His teeth became very brittle, and pieces broke from healthy as well as diseased teeth from very slight causes. Finally, a weakness of the arms and limbs developed in the course of nine months into complete locomotor ataxy. 

Such intricate interactions suggest possible synergisms that could be investigated. Will small amounts of added SDS strengthen the protein network causing final displacement with a nonionic surfactant to occur at higher surface pressures Such studies are needed to imderstand subtle interplays between the mixtures of surfactants encoimtered in commercial food samples. 

Oped by Yang [42]. None of these models attribute the reduction in residual strength to any specific damage mechanism or explain how they cause final failure. 

If the downcomer capacity is inadequate, the level of liquid in this one increases gradually until it limits the liquid flow on the tray above, or on its tray. This, however, increases the entrainment from one tray to the other one and cause finally the flooding. So conditions of flooding can result, either of an inadequate capacity of the downcomer, or of an excessive liquid entrainment in the vapour space. 

Bunsell and Hearle (1971) showed that cyclic loading of nylon commonly gave tensile breaks after the same time as for creep rupture at the peak cyclic load. The exception was when the fibres were cycled from zero load to about 50% of break load. In these circumstances, the break showed a tail on one end, which is typically about five fibre diameters long and had stripped off the other end. Fig. 9a,b. The sequence of failure was first the development of a small transverse crack, which then turned and ran along the fibre at an angle of about 5° to the fibre axis. Fig. 9c. When the crack had crossed half the fibre, the stress on the residual cross-section caused final ductile rupture, Fig. 9d. 

An Official Court of Inquiry was immediately appointed by the Secretary of State for Employment, Michael Foot, to establish the causes and circumstances of the disaster and to point out any lessons... to be learned therefrom. The essential problem faced by the Court was to determine what had caused the rupture of the by-pass. The possibilities investigated were i) rupture of the by-pass assembly through internal pressure ii) rupture of the assembly in two stages a small tear in the bellows (bellows B4) leading to an escape and a minor explosion causing final rupture and iii) rupture of the 8 inch line at the 50-inch split leading also to a minor explosion causing rupture of the by-pass assembly. ... 

As discussed earlier, cause and consequence are closely coupled. However, in some approaches safeguards are not considered initially and only consequences are considered pertinent to all causes. Finally, safeguards are applied to obtain the final recommended action. Normally, it is the prerogative of team leaders to decide when to carry out the consequence analysis. In most cases it is seen that such exercises are done after each subsystem study is complete, so that all causes and consequences can be carefully studied. It is necessary to see if the system goes beyond the intended... 

In some systems, SCC is initiated at a very large number of sites, and the crack tip strain rate is greatly reduced at each individual site, leading to near arrest of the cracks (another reason for crack arrest might be discontinuous segregation or precipitation recall Figure 11.13). Coalescence of two or more cracks is then required to produce a dominant crack that causes final failure [27,167] (Figure 11.40). Statistical physicists are very interested... 

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