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11.
Metallic Na formation in/on NaCl crystals with irradiation by electron or vacuum ultraviolet photons
Shigehiro Owaki Shigeko Koyama Masao Takahashi Masao Kamada Ryouichi Suzuki 《Radiation Physics and Chemistry》1997,49(6):609-615
Metallic Na was formed in/on NaCl single crystals by irradiating them with a variety of radiation sources, namely, 21 MeV electron pulses, an electron beam of 30 keV and photon fluxes in the VUV region. The physical states were analysed using several methods, optical absorption, lifetime measurement of positron annihilation, Auger electron spectroscopy and UV photoelectron spectroscopy. Metallic Na was obtained in different physical states; clusters were formed in bulk, thin layers (islands) and thick layers on the surface. 相似文献
12.
Yorihiko Sasaki Shigehiro Konaka Takao Iijima Masao Kimura 《International journal of quantum chemistry》1982,21(2):475-485
The total (elastic and inelastic) intensity of electrons scattered by CO2 was measured in the s range of 1 to 12 Å?1 and compared with the theoretical intensity calculated from the Hartree-Fock molecular wave function and those calculated for the independent-atom-model (IAM ) molecule. In the range of s ? 4 Å?1 the electron correlation effect on the total scattered intensity was found to be represented by that for the IAM molecule. 相似文献
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Shigehiro Hirano Ko-Ichi Yamamoto Hiroshi Inui Ming Ji Min Zhang 《Macromolecular Symposia》1996,105(1):149-154
The following dry composite beads (diameter 1.0-1-2 mm) were prepared: chitin-CaCO3, chitosan-CaCl2. chitosan-CuCl2, partially N-acetylated chitosan-CuCl2, chitosan-CuSO4, chitosan-Fe3O4, chitin-SiO2. Each of chitosan-CuCl2, chitosan-CuSO4 and chitin-CaCl2 composite beads was treated in aqueous K2CO3 at room temperature to afford a mixture of metal carbonates and hydroxides on chitin or chitosan chain. 相似文献
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Shigehiro Morikawa Toshiro Inubushi Kan Takahashi Hisanari Ishii Shino Shigemori 《Magnetic resonance imaging》1996,14(10):1197-1204
The relationships among tissue edema, lactate accumulation, and intracellular pH in middle cerebral artery (MCA)-occluded rats were investigated with multiecho 1H magnetic resonance imaging and spatially resolved metabolic images constructed by 1H and 31P nuclear magnetic resonance (NMR) chemical shift imaging (CSI). For the effective and sensitive detection of NMR signals from the brain, outer volume suppression (OVS), reduced k-space sampling and proton irradiation were incorporated into the CSI sequences. The consecutive three measurements of calculated T2 image, lactate image, and pH image which were required for 3.75 h were repeated for four cycles of 1–16 h after MCA occlusion. Tissue edema and lactate accumulation in the infarcted region were gradually and consistently increased during the 15-h observation period. In contrast, severe acidosis was already detected on the first pH image (2–4.7 h after MCA occlusion); thereafter, the degree of acidosis became milder and showed no further progression. The dissociation between the time courses of the lactate accumulation and pH decrease was clearly demonstrated by the NMR metabolic images. Acid-base balance in cerebral infarction might be affected not only by lactate production but also by complicated interactions with tissue edema and some other factors. 相似文献
18.
M Fujimoto Y Tsukinoki K Hirose K Kuruma R Konaka T Okabayashi 《Chemical & pharmaceutical bulletin》1980,28(5):1378-1386
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Single crystals of 6H-SiC were epitaxially grown on 6H-SiC substrates in the temperature range of 1500 to 1750°C with gas composition: H2 ≈ 1 l/min, SiCl4 ≈ 1 ml/min, C3H8 ≈ 0.05 ml/min. The grown layers were transparent and mirror-like. The morphology of the grown layer was strongly influenced by the polarity of the substrate surface. Aggregates of trapezoidal crystals were observed on the (000)C surface and a mosaic pattern was observed on the (0001)Si surface. By observing the initial stage of the crystal growth, the growth mechanism of 6H-SiC is discussed. On (000)C surfaces the vertical growth dominates, while on (0001)Si surfaces the lateral growth dominates. 相似文献
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[reaction: see text] The reaction of (o-silylphenyl)acetylene derivatives with lithium naphthalenide undergoes intramolecular reductive cyclization to produce various silaindene derivatives. On the basis of this methodology, a series of silaindene-containing pi-electron systems are synthesized that show intense blue to greenish-blue fluorescence. 相似文献