Density crystal lattice effects

There are, apparently, other effects which play a role, possibly the polarity of the -O- segment in the chain and the topology of the chains in the crystal lattice the magnitude of the interaction forces does not only depend on the nature of the attracting groups, but also on their distance. In this respect a comparison between the crystalline densities of PTHF (1.1 g/cm3) and POM (1.5 g/cm3) is instructive the POM crystal is considerably denser, so that the real interactions play a much bigger role in their effect on the melting point. 

The hydrogenation of spherical particles of an alloy BT5-1 proceeds without the induction period at 773 K with exothermic effect, therefore a temperature in autoclave raises up to 820 K (sample 1—4). The content of hydrogen in hydrogenation products answers the composition Ti(Al,Sn)Hi 8. On the diffractograms of products of hydrogenation only the reflexes of titanium hydride are observed with the constant of a crystal lattice a = 0.4434-0.4437 nm (for TiHL92 a = 0.4448 nm). The reduction of a diameter of alloy particles results in appreciable decrease of time of sample saturation by hydrogen with 4 h at a diameter of particles of 0.8 mm (sample 4) up to 10 min at a diameter of particles of 0.1 mm (sample 1). At that the density of titanium doped by A1 and Sn in... 

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