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Abstract B1-type MX ceramics are composed of transition metals (M) and C, N, and/or O (X) occupying the M and X sites, respectively, and having M–X nearest neighbor (NN) bonds and M–M and X–X next nearest neighbor (NNN) bonds. Substitution of the elements and the formation of structural vacancies in B1-type ceramics change the numbers and strengths of the bonds, leading to novel properties. The change in elastic modulus of off-stoichiometric TiC in equilibrium with a Ti–Mo solid solution phase was experimentally investigated based on the rule of mixtures from the Voigt model. The experimentally obtained values agreed well with the results of density functional theory calculations. The bulk modulus (K) of TiC increased from 205.6 to 239.2 GPa as the fraction of Ti sites occupied by Mo increased from 0.11 to 0.33, whereas the Young’s modulus (E) and the shear modulus (G) remained nearly constant. On the other hand, all three elastic moduli decreased with increasing vacancy fraction at the C sites. These results suggest that the M–X bond strength should be the dominant factor in these moduli and the effect of M–M bond on K is greater than that of G and E.

The injury caused by the re-establishment of blood flow to ischaemic tissues is larger than the injury to the tissues caused during ischaemic period. This injury, also known as reperfusion injury, is related to frostbite, multiple organ failure, hypovolaemia and myocardial infarction. The reperfusion injury is enhanced by the removal of neutrophils, indicating that neutrophils have a causal role. The interleukin 8, a recently discovered chemotactic cytokine, is an important neutrophil synthesized by different types of human cells. Neutrophil infiltration and pulmonary structure destruction are caused by the reperfusion of ischaemic lung.

We performed in situ compression of interstitial-free steel nanoblades using transmission electron microscopy (TEM) in order to determine the relation between the evolution of the dislocation structures and the flow stress during deformation. In the early stage of deformation, the sample deforms elastically with a few dislocation motions. The dislocation multiplication processes have been discussed. Remarkable plastic softening with increasing dislocation density is observed after the maximum stress is reached, which can be understood as a situation in which the dislocation density is the dominant factor affecting the softening based on the Johnston-Gilman model. [ABSTRACT FROM AUTHOR]