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121.
The 172 nm ultraviolet (UV) excimer light was exposed to polyethylene (PE), polypropylene, poly(ethylene terephthalate) and
nylon 6 surfaces in ambient air. Changes in the contact angle and particle deposition in liquid due to UV treatment were investigated
from the viewpoints of wettability and detergency. For all polymers, the wettability and the acid-base component of the surface
free energy evaluated by the contact angle measurements increased remarkably by UV treatment of 1 min. From surface analyses
of the polymer surfaces by X-ray photoelectron spectroscopy and atomic force microscopy, oxygen concentration was found to
increase after UV treatment, whereas little topographical change was observed. The deposition of PE and nylon 12 particles
onto the polymer surface was examined, in situ, in water, water/ethanol mixture, ethanol and n-heptane. Although the number
of deposited particles was largely dependent on the kinds of the particle, the substrate and the liquid, a significant decrease
in the deposition due to UV treatment was confirmed in any system. 相似文献
122.
Steffen Breitfelder AnneC. Schuemacher Thomas Rlle Makoto Kikuchi ReinhardW. Hoffmann 《Helvetica chimica acta》2004,87(5):1202-1213
{[2‐(Trimethylsilyl)ethoxy]methyl} (SEM)‐protected pederic acid 16 was prepared by deriving the stereogenic center at C(7) from mannitol and those at C(2) and C(3) (mycalamide numbering) from trans‐2,3‐dimethyloxirane. Routes to pederamides involving a late oxygenation at C(7) were explored. 相似文献
123.
Photo- and thermal-diffusion effects of Ag and Cu into As2S3 bulk glass have been studied. It has been clarified that the photo-diffusion process is attributed to a purely optical effect. Some differences in diffusing process between Ag and Cu have been clearly shown both for the photo- and thermal-diffusions. 相似文献
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D. M. Poirier J. H. Weaver Koichi Kikuchi Yohji Achiba 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,26(1):79-83
X ray photoemission spectra show ~10 valence band features in C60 and C84 films, although they are less distinct in C84 because of the increased number of valence electrons and the decreased molecular symmetry. The presence of inequivalent carbon atoms in C84 is reflected by the fact that the C 1s main line is ~0.2 eV wider than in C60. The C 1s satellite region of C84 exhibits four features within 15 eV of the main line and shows that the HOMO-LUMO π-π* excitation energy of C84 is ~0.5 eV smaller than in C60. Potassium 2p spectra for K-doped C84 films suggest the formation of a phase with composition K3C84 with two spectroscopically-distinguishable K sites. A new spectral feature emerges when the K content is increased beyond K3C84, suggesting a phase transition and a saturated composition of K6C84, as for KxC60. These similarities are intriguing since KxC84 is insulating for all x while K3C60 is metallic and superconducting. 相似文献
127.
Masae Kikuchi Kenji Hiraga Yasuhiko Syono Humihiko Takei 《Journal of solid state chemistry》1985,56(3):390-393
Electron microscopic observations were performed on shocked and unshocked BaZnGeO4 (BZG). Particular attention was given to the superlattice relation. A specimen shocked to the pressure range of 19–27 GPa, showed a small distortion from the original hexagonal lattice, to an orthorhombic symmetry. Along with this distortion, weak superlattice reflections along the direction in the unshocked BZG were found to disappear completely, while the repetition mode of superlattice reflections along the direction ([110]1 direction in the hexagonal structure) as found to change from three to six, and then to four, with increasing shock pressure. A single crystal—single crystal transition, on a submicrometer scale, was shown to occur due to a small displacement of atoms during shock process. 相似文献
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