SN1-type mechanism for the carbon-carbon bond cleavage of tetrakis(4-methylphenyl)ethanone cation radical. A laser flash photolysis study

On the basis of measurements of rate constants for carbon-carbon bond cleavage of tetrakis(4-methylphenyl)ethanone cation radicals generated by pulsed laser excitation with sensitizers in solution, an S_N1-type mechanism for the bond cleavage is proposed.     

Dynamic studies of angle-ply laminates including flexure–torsion coupling using laser holography

Laser holographic interferometry has been applied to experimentally investigate the effect of flexure–torsion coupling stiffnesses on the vibrational characteristics. Test specimens are two special types of angle-ply laminates, which enables us to examine the influence by a flexure–torsion coupling term alone. The theoretical analysis by a finite element method is also conducted to support the experimental results. It is found that the effect of coupling stiffnesses on the natural frequencies is comparatively small. On the other hand, the mode shapes are strongly affected by the coupling terms depending on both the fiber orientation and the aspect ratio of a cantilevered laminate.     

Preparation of Mg3 129TeO6 Mössbauer source

The preparation of Mg₃ ¹²⁹TeO₆ sources for iodine Mössbauer spectroscopy is described, and the after-effect in¹²⁸Te(n,)^{129 129m}Te neutron activation is discussed. The results show that the annealing procedure is necessary for eliminating the after-effect induced by the capture-rays.