Septorine and N-methoxy septorine,substituted pyrazines from the fungus Septoria nodorum berk

On the basis of ¹H nmr correlations with synthetic analogs, structures $\text{1}$ and $\text{2}$ are proposed for septorine and N-methoxy septorine, two p-hydroxybenzoyl 1-isobutyl substituted pyrazines obtained from the fungus $\text{Septoria nodorum}$ Berk, a parasite of wheat.     

Introduction of phosphorus into the polyethyleneterephthalate molecule—II. A study of the influence of the modifier on the properties of polyethyleneterephthalate

The influence of the sodium salt of diethylphosphite, introduced as modifier, on the properties of polyethyleneterephthalate molecule is examined. It is shown that the detrimental effect of the salt on the normal progress of the reaction can be reduced if it is introduced at a later stage of the process. The phosphorus-containing polyethyleneterephthalate so obtained exhibits significantly improved resistance to combustion.     

Error bounds in the approximation of eigenvalues of differential and integral operators

Various methods of approximating the eigenvalues and invariant subspaces of nonself-adjoint differential and integral operators are unified in a general theory. Error bounds are given, from which most of the error bounds in the literature can be derived. Computable error bounds are given for simple eigenvalues, and trace formulae are used to improve the accuracy of the computed eigenvalues.     

The quantization of the Gürsey model

The Gürsey model, a conformally invariant pure spinor model in four dimensions, is quantized to result in an asymptotically free theory.     

Neutron matter densities in the even Ni isotopes

Elastic scattering of 1.047 GeV protons is studied on the isotopically enriched ^58,60,62,64Ni isotopes. A spin independent Glauber theory analysis allowed the extraction of nuclear matter densities for these targets.     

The synthesis and crystal structure of triphenylvinyltin

Triphenylvinyltin has been prepared by an improved method. It crystallizes in the Pbn2₁ space group; the crystal contains two non-equivalent molecules which have almost the same conformation. The latter are compared with the conformations in tetraphenyl-methane, -silane, -germane, -tin and -lead.