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ABSTRACT A cDNA encoding pheromone Δ9 acyl‐CoA desaturase, SlitKPSE was isolated from sex pheromone gland of the tobacco cutworm, Spodoptera liturawhich uses a diene unsaturated fatty acid (UFA) derivative, Z9E11‐14 : 2 as a major pheromone component. The fulllength open reading frame coding region of SlitKPSE was inserted in a yeast shuttle vector, YEpOLEX, and two kinds of yeast (Saccharomyces cerevisiae) mutant strains were transformed with the recombinant vector. In the desaturase‐deficient ole1 strain, SlitKPSE expressed a complementary enzyme producing two kinds of diene UFAs, more 9–16 : 1 and less 9–18 : 1 at a ratio of 1 : 0.74 exhibiting a typical functional characteristics as one of the pheromone Δ9 acyl‐CoA desaturase lineage group, KPSE, but no Δ9 14C monoene was detectable because of too small amount of 14C saturated fatty acid precursor to be reliably used by SlitKPSE in the transformed cells. However, the another transformed yeast strain elo1 which is deficient of elongase 1, an enzyme converting 14C to 16C hydrocarbon substrate, was supplemented with some myristic acid (14 : 0) in the medium, and produced a significant amount of 9–14 : 1 in due to a much enhanced level of the 14C substrate suggesting that SlitKPSE may be responsible for making the Δ9 double bond on the diene pheromone component.

The initial adsorption of Ba on the Si(001)2 ×1 surface at 870°C has been studied by low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy (XPS), and angle-integrated ultraviolet photoelectron spectroscopy (AIUPS). The valence band, Si and Ba core level spectra and the work-function change (??) were measured. The double domain (DD) (2 ×3)-, DD c(2×6)- and DD (2×1)-Ba surfaces appeared depending on the Ba coverage. AIUPS results show that both DD (2 ×3)-Ba and DD (2 ×1)-Ba surfaces are semiconducting in nature. The intensity ratio data of XPS core levels (Ba 3d/Si 2p) and the work-function change data reveal that the Ba coverages of the (2×3)-Ba and the DD (2×1)-Ba surfaces are 1/3 ML and 1/2 ML, respectively. The AIUPS spectra show that the structural models with Ba coverage of 1/3 ML and 1/2 ML, at the bridge sites between two Si dimers are reasonable for the (2 ×3)-Ba and the (2 ×1)-Ba surfaces, respectively.

We have investigated Cs-induced reconstruction on the Si(113)3×2 surface using low energy electron diffraction (LEED) and X-ray photoelectron spectroscopy (XPS). For Cs deposition at room temperature, the (3×1) LEED pattern was observed for a wide Cs coverage range. At high substrate temperatures, the (3×1), (1×5+2×) and (2×2) phases were observed with increasing Cs deposition time. The relative Cs saturation coverages of (3×1)-Cs at RT and (2×2)-Cs at 300°C were measured from Cs 3d/Si 2p core level XPS intensity ratios. The results are summarized in a phase diagram as a function of the Cs deposition time.