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The multiple-plane-wave phase-shift model of Sorbello is used to predict Dingle temperatures for several orbits on the Fermi surface of Mg. The pseudo-wave-functions for this calculation are obtained from a ten-plane-wave nonlocal pseudopotential model for pure Mg. The experimental results are well fitted by a two-parameter phase-shift model while phase shifts obtained from a model potential yield a greater anisotropy than is observed experimentally.

The De Haas-Van Alphen effect in Al based alloys were studied. Measurements on dilute alloys of Zn and Si in Al are reported. The results are discussed in terms of the 3rd zone Fermi surface of Al proposed by Ashcroft and the rigid band theory of alloys with which they show generally good agreement. In contrast to these results, recent measurements of the steady magnetic susceptibility and low temperature specific heat of more concentrated Al alloys by Blythe et al. have shown major departures from the predictions of the rigid band model. Attention is drawn to this striking difference without proposing a solution.

The de Haas‐van Alphen effect is used to determine the change of the Zn Fermi surface parameters in dilute Zn Cd alloys containing up to 1.2 at.% Cd. Its application in observing the change of the matrix band structure during room‐temperature aging is demonstrated. The presence of local concentration gradients and strain fields in the matrix during precipitation produce strong phase‐smearing effects.

Gibberella cyanogena, the ascomycetous stage of Fusarium sambucinum Fuckel f. 6 Wr., has been previously reported1 to be bisexual (hermaphroditic) and self-sterile. In other words, single-ascospore and monoconidial cultures of this fungus belong to one or other of two mating types, designated m.t.A and m.t.a, both of which may function as male and female but are self-sterile. For the production of fertile perithecia under laboratory conditions it is necessary to bring together cultures of the two mating types and maintain them under the appropriate environmental conditions.

The crystal structure of phase IV (polar α or δ phase) poly(vinylidene fluoride) was studied by x-ray diffraction. Oriented phase IV was obtained by orienting phase II (α phase) and then corona poling at approximately 2 MV/cm. The resulting material is a mixture of phases I, II, and IV. Infrared spectra indicate that phase IV has the same chain conformation (TGTG') as phase II. The reflections of phase IV can be indexed in an orthorhombic unit cell with lattice constants similar to the phase II lattice constants a = 0.496 nm, b =0.964 nm, and c (chain axis) = 0.462. There are two chains in this unit cell. The two chains pack with the chain dipole moments parallel. Three different models of chain packing were investigated: both chains up, one up and one down, and a statistical up-down packing. It was found that to within a 97% confidence level, the chains do pack with a statistical up-down packing.