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We present the results of six-epoch Very Long Baseline Array (VLBA) observations of 3C 66A. The high-resolution Very Long Baseline Interferometer (VLBI) maps obtained at multi-frequency (2.3, 8.4, and 22.2 GHz) simultaneously enabled us to identify the brightest compact component with the core. We find that the spectrum of the core can be reasonably fitted by the synchrotron self-absorption model. Our VLBA maps show that the jet of 3C 66A has two bendings at about 1.2 and 4 mas from the core. We also give possible identifications of our jet components with the components in previous VLBA observations by analysing their proper motions. We find consistent differences of the position from the core in one component between different frequencies at six epochs.

We used Monte Carlo simulation code DEGAS and studied the neutral particle behavior in the Compact Helical System (CHS) three-dimensionally. In contrast to other helical devices, the CHS plasma in the standard configuration has contact with the inner vacuum vessel wall like the material limiter used in many Tokamaks and the neutral recycling becomes dominant there. As the intensity of neutral recycling changes also along toroidal direction, we extended our previous simulation model geometry three-dimensionally and compared the results of these models. We found the variation of the gap between the vacuum wall and main plasma enhanced toroidal transport of hydrogen molecules and atoms. As the formation of the edge transport barrier (EBT) discovered recently in CHS is characterized by a clear drop in Hα emissions, it is interesting to study the relationship with the profile of atomic/molecular hydrogen and the Hα emission profile. We estimated emission not only from excited hydrogen atoms but also from dissociated molecules with a collisional radiation model. We found that our Hα detector signal in CHS mostly came from excited atoms and that the emission profile largely changed with the ETB formation.

Diamond-like carbon thin films were prepared by pulsed-laser evaporation. In this method a carbon target was irradiated by a XeCl laser with a power density of 3×108 W/cm2 and carbon atoms, together with a small number of ions, were produced. Deposition rates and film properties changed sensitively with substrate temperature. The films deposited at 50°C were diamond-like, having reasonable hardness, high refractive index (2.1–2.2 at 633 nm), optical transparency in the infrared, electrical resistivity of 108 O cm and chemical inertness (no dissolution in a HF:HNO3 solution). The band gap measured from optical absorption was 1.4 eV. Raman spectrum and infrared absorption, whose features varied with the substrate temperature, were also measured. The films were amorphous and no crystallinity was observed, as confirmed by x-ray diffraction, transmission electron diffraction and Raman spectroscopy. Hydrogen atoms were incorporated in the films with a typical H/C ratio of 0.3. The application of a negative bias to the substrate modified the deposition due to the presence of ions.

A prostaglandin F (PGF) synthase was recently purified from bovine lung that catalyzed the reduction of both PGH2 and PGD2 but at different active sites on the enzyme. In view of the recent finding that PGD2 is stereospecifically reduced to a unique biologically active compound, (5Z, 13E)-(15S)-9 alpha, 11 beta, 15-trihydroxyprosta-5,13-dien-1-oic acid (9 alpha,11 beta-PGF2 or 11-epi-PGF2 alpha), by a human liver cytosolic enzyme, detailed characterization of the products formed from PGH2 and PGD2 by the bovine lung PGF synthase was carried out. Chromatographic characteristics of the products formed and stereochemical analysis procedures using mass spectrometry indicated that the enzyme stereospecifically reduces PGH2 to PGF2 alpha, whereas PGD2 is stereospecifically converted to 9 alpha,11 beta-PGF2. The finding that this enzyme catalyzes the formation of both C-11 hydroxy epimers of PGF2, albeit from different substrates, is of interest in that these two compounds may exert different biological actions.

It was concluded that the conversion of 2,6-bis-(phenethylamino)-2,5-heptadiene-4-one (BPH) into N-phenethyl-lutidone (PL) in 80 percent ethanol is accounted for in terms of aminolysis reaction. In general, the aminolysis reaction proceeds viaa two-step reaction path involving a gem-diamine as an intermediate. The first step in the above reaction of BPH becomes reversible by the addition of excess β-phenethylamine (PE-NH). The mechanistic pathway was discussed. Moreover, it was supported with kinetic investigation using an analog computer that BPH is the most important intermediate in the conversion of 3-(1-phenethylamino)ethylidene-6-methyl-3H-pyran-2,4-dione (Schiff's base) to PL in the presence of large excess PE-NH.

Zusammenfassung Zur bequemen Übersicht über die Größen der Knicklasten für die auf allen vier Seiten gleichmäßig gedrückte quadratische Platte mit verschiedenen Randbedingungen sind in der folgenden Tabelle die im vorigen Abschnitte vom Verfasser sowie früher von anderen berechneten numerischen Ergebnisse zusammengestellt.

Zusammenfassung Zum bequemen Überblick Über die bisher ermittelten Rechenergebnisse für die quadratische Platte sind die den verschiedenen Schwingungsarten entsprechenden Werte vonΜ nebst den Knotenlinien in Tabelle 5 noch einmal zusammengestellt.

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Treatment of the lactones (I), alcohols (VI), or the acetoxyoctadiene (VIII) with triphenylphosphine hydrobromide (II) results in the formation of the (primary alkyl)triphenylphosphonium bromides (III), (VII), or (IX).

The aromatic aldehyde (I) is coupled with O‐methyloctopamine hydrochloride (II) and then reduced to give the amino alcohol (III) which does not cyclize upon treatment with conc.

Both the title compounds are synthesized and the protecting properties of the adamantyl groups are investigated.

The alkaloid (I) is isolated from the leaves of the title plant and its structure is established by X‐ray diffraction (space group P212121, Z=4).