Cleavage failure

The principal failure modes of bolted joints are (1) bearing failure of the material as in the elongated bolt hole of Figure 7-44, (2) tension failure of the material in the reduced cross section through the bolt hole, (3) shear-out or cleavage failure of the material (actually transverse tension failure of the material), and (4) bolt failures (mainly shear failures). Of course, combinations of these failures do occur. 

Uetake, Y., Sluder, G. (2004). Cell cycle progression after cleavage failure mammalian somatic cells do not possess a tetraploidy checkpoint . The Journal of Cell Biology, 163, 609-615. 

Examples of this type of application abound in the literature. Segregation of impurities in metals and alloys often occurs at grain boundaries. A study of the embrittlement and stress-failure of a tungsten sample showed a nearly uniform distribution of phosphorus across the sample, except for certain grains that appeared to be completely free of it this complete absence of phosphorus can be interpreted as related to cleavage failure at these points. 

Figure 113 Failure modes in composite bolted joints (a) bearing failure, (b) net-tension failure, (c) shear-out failure, (d) cleavage failure, (e) fastener puU-through, (f) bolt failure.

MgBr2-Et20, Mc2S, CH2CI2, it, 75-96% yield. " The failure of this substrate to undergo cleavage with the typical conditions was attributed to the presence of the 1,3-diene. Acetonides and TBDMS ethers were found to be stable. 

Detailed discussion of these findings will be presented elsewhere. Here we only wish to point out that responses to a hydrogen donor tend to be critically affected by minor structural differences between the compounds. Thus, while diphenyl ether remains substantially unaffected by the donor, its hydroxy-derivatives (phenoxy phenols) often display fairly high reactivity. Taken in conjunction with the failure of low-rank coals (7) and phenoxy phenols (10) to suffer reductive cleavage when treated with sodium in liquid ammonia, this lends some support for the existence of phenoxy phenol entities in low rank coals. 

Clear-liquor advance, 5 124 CLEAR process, 23 576 Clear Skies Legislation, 26 45 Cleavage fracture, as failure mechanism, 26 983... 

The origin of the persistent radicals which are produced in low yields is of some interest. Simple photochemical silicon-carbon bond cleavage lacks precedent and is not consistent with the failure to observe any alkane or 1-alkene in the photolysis mixture. While the latter could not be expected to survive in the irradiated solution, the former would. A possible route involving photochemical 1,1-reductive elimination is described below. 

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