Selbstvernetzende Polymere. 2. Mitt. Copolymerisation von 2,3-Epoxy-1-propyl-methacrylat mit 2-Vinyl-5-?thylpyridin bei hohem Druck

Ohne Zusammenfassung     

Non-specific abnormality (so called "hot spot") on 99mTc-phytate liver scintigraphy of patients associated with superior vena caval syndrome (author's transl)

We have recently observed two patients with superior vena caval syndrome who showed a unique abnormality, so called "Hot Spot", on the 99mTc-phytate liver scintigraphy. This phenomenon seems to be related to the collateral venous circulation. It is supposed that its manifestation depends on the degree of venous dilatation of the chest and abdominal wall.     

Closed maps on metric spaces

The following result is proved: Let Y be the image of a metric space X under a closed map f. Then every ?f^-1(y) is Lindelöf if and only if Y has a point-countable k-network.     

The electronic structures of cis-polyacetylene

The electronic structures of two possible forms of the so-called $\text{cis}$-skeletal polyacetylene ($\text{cis}$-polyacetylene) are investigated on the basis of the tight-binding LCAO-SCF-MO method under the CNDO/2 version. The analyses of the total energies per unit cell, the π bond orders and the interatomic interaction energies as to the both forms predict the $\text{cis}$-transoid backbone for the $\text{cis}$-polyacetylene. The examination of the patterns of particular molecular orbitals of the hypothetical $\text{cis}$-polymer with equal C-C bond lengths also supports the $\text{cis}$-transoid form.     

Reversible photo-induced volume changes in evaporated As2S3 and As4Se5Ge1 films

Reversible photo-induced volume changes have been observed accompanying reversible optical absorption edge shift produced by successive cycles of band gap illumination and annealing for well-annealed evaporated As₂S₃ and As₄Se₅Ge₁ films. The As₂S₃ film shows an increase in its volume by illumination, while As₄Se₅Ge₁ film shows a decrease. Qualitative discussion has been given in connection with pressure-induced optical constant change.