A comparative report on an on-line retrieval service employing two distinct software systems.

A subjective evaluation comparing the National Aeronautics and Space Administration RECON and National Library of Medicine ELHILL 2 on-line information retrieval systems is presented as they relate to the delivery of a major service dealing with a collection of toxicological bibliographic references (TOXLINE). Comparisons of file structure, response time, command language, system environment, and other relevant features are made based upon actual experience with both systems.     

Phase equilibria in the systems ZnSMnS,ZnSCuInS2, and MnSCuInS2

Using high purity ZnS, MnS, Cu₂S, and In₂S₃, the binary systems were examined between 400 and 1300°C using evacuated fused silica capsules to contain intermediate mixtures. X-Ray and microscopic examination of samples at room temperature permitted the probable phase relations to be established. The extent of the very important stability regions for zinc blende and wurtzite solid solutions was firmly established and in the system MnSCuInS₂, the stability fields for the intermediate γ-MnS (wurtzite) solid solutions and CuInS₂ solid solutions were determined.     

Reaktion an Ziegler-Natta-Katalysatoren. 12. Mitt. Anwendung der Olefin-Metathese zum Nachweis einer radikalischen Aralkylierung von 1,4-Polybutadien

Ohne Zusammenfassung     

Trends in Radiation Polymerization

Previously it was generally assumed that high energy radiation could only initiate radical polymerization in solutions of monomers. However, examples of radiation-induced polymerization have recently become known that proceed via an ionic mechanism. Thus, solutions of a monomer can be polymerized ionically, preferably in the presence of a solid, at low temperatures. Suprisingly, this may also be accomplished with ultra-pure, mainly anhydrous systems, even at room temperature. The nature of the ions has not yet been fully elucidated.     

Ultrafast Fiske effect in semiconductor superlattices

The current flowing across a semiconductor superlattice in tilted electric and magnetic fields is known to exhibit resonant enhancement, when Landau states of neighboring wells align at certain ratios of the field strengths. We show that the ultrafast version of this effect, in which coherent electron wave packets are involved, has a profound analogy to the Fiske effect in superconductor Josephson junctions and superfluid weak links, in that the coupling of the tunneling-induced charge oscillations (magneto-Bloch versus Josephson oscillations) to another oscillator (in-plane cyclotron oscillations versus external oscillator modes) opens an elastic rectifying transport channel. We explore the superlattice effect both theoretically and experimentally, and find that the transient self-induced current can be adequately modeled if the damping of both types of coupled electron oscillations is properly taken into account.