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991.
Six steroid itN-acctylglueosaminides, pavoninins-1 to -6, have been isolated from the defense secretion of the sole P. pavoninus guided by ichthyotoxicity and hemolytic activity, and their structures determined to be 1–6 by spcctroscopic studies and chemical correlations. The pavoninins are considered to be the factors responsible for the repellent property of the sole against predatory fishes. 相似文献
992.
993.
Morimoto T Yoshikawa K Murata M Yamamoto N Achiwa K 《Chemical & pharmaceutical bulletin》2004,52(12):1445-1450
Axially chiral biphenyldiphosphine ligands bearing diphenylphosphino group(s) and/or dicyclohexylphosphino group(s) were prepared in enantiomerically pure form starting from 2,6-dimethylnitrobenzene via 8 steps: iodination, reduction, methoxylation through diazotization, Ullmann coupling, bromination, phosphorylation, optical resolution, and silane reduction, and the obtained ligands were used in rhodium-catalyzed asymmetric hydrogenation. 相似文献
994.
Kazuo?AkutagawaEmail author Boris?Botvinnik Osamu?Kobayashi Harish?Seshadri 《Journal of Geometric Analysis》2003,13(1):1-20
For a compact manifold M ofdim M=n≥4, we study two conformal invariants of a conformal class C on M. These are the Yamabe constant YC(M) and the Ln/2-norm WC(M) of the Weyl curvature. We prove that for any manifold M there exists a conformal class C such that the Yamabe constant YC(M) is arbitrarily close to the Yamabe invariant Y(M), and, at the same time, the constant WC(M) is arbitrarily large. We study the image of the mapYW:C→(YC(M), WC(M))∈R 2 near the line {(Y(M), w)|w∈R}. We also apply our results to certain classes of 4-manifolds, in particular, minimal compact Kähler surfaces of Kodaira dimension 0, 1 or 2. 相似文献
995.
996.
Assuming that a macrovariable follows a Markovian process, the extensive property of its probability distribution is proved to propagate. This is a generalization of the Gaussian properties of the equilibrium distribution to nonequilibrium nonstationary processes. It is basically a WKB-like asymptotic evaluation in the inverse of the size of the macrosystem. Evolution of the variable along the most probable path and fluctuation properties around the path are considered from a general point of view with an emphasis on the relation of nonlinearity of evolution and the associated fluctuation. Anomalous behavior of the fluctuation is discussed in connection with unstable, critical, or marginal states. A general treatment is given for the asymptotic properties of relaxation eigenmodes. 相似文献
997.
Kazuo Itoh Morio Nakayama Masahiko Chikuma Hisashi Tanaka 《Fresenius' Journal of Analytical Chemistry》1986,325(6):539-543
Summary An improved fluorimetric method for the determination of selenium in estuary sediments and sedimentary core samples is described. For the separation of selenium, coprecipitation with tellurium-ascorbic acid method gave satisfactory results. The status of the pollution caused by selenium in Nagoya area, which is one of the most industrially active areas in Japan, was estimated, based on the results obtained with this method. Several g/g of selenium were determined in the sediments. Interferences by foreign ions were eliminated by the coprecipitation procedure. Selenium added was recovered by 95–101%.
Selenbestimmung in Sedimenten mit Hilfe der Fluorimetrie mit 2,3-Diaminonaphthalin nach einer verbesserten Vorbehandlung durch Tellur-Mitfällung
Zusammenfassung Gehalte bis zu mehreren g/g Selen wurden nach dem verbesserten Verfahren in den Sedimenten des Hafens von Nagoya bestimmt. Störungen durch Fremdionen wurden durch das Mitfällungsverfahren mit Tellur/Ascorbinsäure verhindert. Zugesetztes Selen wurde zu 95 bis 101% wiedergefunden.相似文献
998.
999.
1000.
Tetsuji Kametani Kazuo Kigasawa Mineharu Hiiragi Haruhide Ishimaru Toshihisa Nakamura Keiko Shirayama 《Journal of heterocyclic chemistry》1979,16(3):581-584
In order to examine their effect on carrageenin-induced edema in rats, 4-(1-oxo-2-isoindolinyl)-phenyl derivatives were synthesized. 2-Hydroxy-3-[4-(1-oxo-2-isoindolinyl)phenyl]butyramide was found to be more effective than phenylbutazone. 相似文献