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281.
Shuji Saito 《Inventiones Mathematicae》1986,85(2):379-414
282.
LetK be a connected graph. A spanning subgraphF ofG is called aK-factor if every component ofF is isomorphic toK. On the existence ofK-factors we show the following theorem: LetG andK be connected graphs andp be an integer. Suppose|G| = n|K| and 1 <p < n. Also suppose every induced connected subgraph of orderp|K| has aK-factor. ThenG has aK-factor. 相似文献
283.
The reaction between glass-like carbon (GC) and chlorine trifluoride (ClF3) gas was investigated with weight measurements, surface analysis, and gas desorption measurements, where the ClF3 gas is used for the in situ cleaning of tubes in silicon-related fabrication equipment. From Auger electron spectroscopy and X-ray photoelectron spectroscopy measurements, a carbon mono-fluoride, –(CF)n–, film near the surface of GC is considered to be grown onto the GC surface above 400 °C by the chemical reaction with ClF3, and this thickness of the fluoride film depends on the temperature. The grown fluoride film desorbs by annealing in a vacuum up to 600 °C. Although GC is apparently etched by ClF3 over 600 °C, the etch rate of GC is much lower than that of SiC and quartz. 相似文献
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287.
Y. Nakanishi Y. Kitagawa Y. Shigeta T. Saito T. Matsui H. Miyachi T. Kawakami M. Okumura K. Yamaguchi 《Polyhedron》2009,28(9-10):1714-1717
The origin of a ferromagnetic interaction between Cu2+ ions in the Cu2+–DNA system which reported by Tanaka et al. is examined by using DFT calculations. In order to consider effects of an entanglement and a dis-entanglement of the double helix chain, three types of structural disorders i.e. distance, rotation angle and discrepancy in XY-plane, are considered in the model dimer structure. All calculated results show that Jab values are weak anti-ferromagnetic couplings. Boltzmann distribution simulation indicates that the high spin (HS) species exist 21% at 1.5 K by thermal excitation within the model structure. 相似文献
288.
Formation of carboxamides of a variety of carboxylic acids with the coupling reagent BBDI is described. This procedure permits a one pot and simple operation without the need of any bases and no base was required for even use of amine hydrochlorides. In addition, an approach to BBDI-catalyzed carboxamidation is examined. 相似文献
289.
Masayuki Yamada Sugako Aramaki Tomoo Hosoe Masahiko Kurosawa Isao Kijima-Suda Koichi Saito Hiroyuki Nakazawa 《Analytical sciences》2008,24(7):911-914
Fluoxymesterone, an anabolic steroid with the 17alpha-methyl,17beta-hydroxy group, has been developed as an oral formulation for therapeutic purposes. However, it is also used illegally in racehorses to enhance racing performance. In this study, we detected 9alpha-fluoro-17,17-dimethyl-18-norandrostane-4,13-dien-11beta-ol-3-one by gas chromatography/mass spectrometry (GC/MS), which has not been reported as a fluoxymesterone metabolite so far in horse. It was synthesized for use as a reference standard, and characterized on the basis of (1)H NMR and (13)C NMR spectra, as well as GC/MS EI mass spectra of TMS derivatives. It was excreted as the main metabolite in horse urine, and its reference standard could be synthesized easily. Therefore, this metabolite could be a useful target for a doping test of fluoxymesterone in racehorses. 相似文献
290.