High-resolution x-ray photoelectron spectroscopy (XPS) at 6 keV photon energy has been realized utilizing high-flux-density x rays from the third generation high-energy synchrotron radiation facility, SPring-8. The method has been applied to analysis of high-k HfO2/interlayer/Si complementary metal–oxide–semiconductor gate-dielectric structures. With the high energy resolution and high throughput of our system, chemical-state differences were observed in the Si 1s, Hf 3d, and O 1s peaks for as-deposited and annealed samples. The results revealed that a SiOxNy interlayer is more effective in controlling the interface structure than SiO2. Our results show the wide applicability of high resolution XPS with hard x rays from a synchrotron source.

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The infrared depletion spectrum of the aniline dimer, formed in a supersonic jet, has been recorded in the N−H stretch region by combining infrared laser excitation and resonant two-photon ionization/time-of-flight mass spectrometry. Only two bands have been found at 3394.0 and 3465.9 cm-1 (±0.5 cm-1) in the region 3130−3530 cm-1. These are red-shifted by 27.8 and 42.3 cm-1 from the symmetric and asymmetric NH stretching vibrations of the aniline monomer, respectively. A configuration with mutual NH2···π bonds and phenyl groups stacked in parallel is suggested for the ground-state aniline dimer.

Glucose transport enhancers were searched for in Lagerstroemia speciosa, a Philippine local herbal medicine used for diabetes mellitus. Bioassay-guided fractionation of the aqueous acetone extract of the leaves afforded three active ellagitannins, lagerstroemin, flosin B and reginin A, identified by NMR and optical rotation. These compounds increased glucose uptake of rat adipocytes, and could be responsible for lowering the blood glucose level.

The microwave spectrum of BF2OH has been observed and assigned. The rotational constants of the isotopic species 11BF216OH, 10BF216OH, 11BF216OD, 10BF216OD, 11BF218OH, and 10BF218OH have been determined. The inertial defects prove that the molecule is planar. Assuming the two BF bond lengths are the same, the bond distances and angles are found to be: rBF = 1.32 Å, rBO = 1.34 Å, rOH = 0.94 Å, ∠FBF=118°, ∠BOH=114.1°, ∠FBO=122.8° (this is the angle cis to the OH). The dipole moment is 1.86± 0.02 D. The dipole moment makes an angle of 50° with the BO bond with dipole moment line on the same side of the BO bond as the hydrogen.