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排序方式: 共有198条查询结果,搜索用时 15 毫秒
21.
N. Inoue T. Ninomiya S. Kashiwabara R. Fujimoto 《Applied Physics A: Materials Science & Processing》1999,69(7):S609-S612
The crystalline properties of Ta2O5 thin films deposited by an off-axis aperture-installation-type pulsed laser deposition technique are investigated and the results are compared with the results for films deposited by the conventional on-axis technique. No significant difference in the substrate temperature dependence is seen between films deposited on-axis or off-axis at a pulse repetition frequency of 30 Hz. When the repetition frequency is lowered, the degree of c-axis orientation is increased in both films. This tendency is more pronounced in the off-axis films. Therefore it is found that the off-axis aperture-installation-type pulsed laser deposition technique is effective not only for decreasing the density of droplets, but also for obtaining more highly c-axis-oriented crystalline films. 相似文献
22.
Fujita S Ninomiya M Efdi M Ohguchi K Nozawa Y Koketsu M 《Natural product research》2010,24(17):1630-1636
Six chemical constituents were isolated from Enicosanthum cupulare (King) Airy-Shaw. The structures of the isolated compounds were determined using 1D, 2D-NMR and were found to be identical to those previously reported for these compounds. Three aporphine alkaloids, O-methylmoschatoline, liriodenine and oxostephanine were isolated from this plant for the first time. In addition, we examined the effects of these compounds on melanogenesis in murine B16 melanoma cells; O-methylmoschatoline increased melanin content in these cells. 相似文献
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Hiraoka K Ninomiya S Chen LC Iwama T Mandal MK Suzuki H Ariyada O Furuya H Takekawa K 《The Analyst》2011,136(6):1210-1215
This paper deals with the dielectric barrier discharge (DBD) ion source composed of the outer cylindrical dielectric tube and the inner grounded metallic tube electrode. The sample gas is supplied through the inner ceramic tube. In this ion source, the DBD plasma is localized in the DBD tube so that the sample gases can be ionized just outside of the ceramic tube by the DBD excited helium gas without being exposed in the plasma jet. Besides, ambient air does not take part in the ionization of the sample vapor because ionization takes place inside the DBD ion source. Thus, this method is totally free from contaminants in ambient air. It was found that this ion source is capable of soft, high-sensitivity, and reproducible ionization. Application of this technique to the analysis of methamphetamine, carbaryl and basil leaf was given. 相似文献
26.
Nakamura S Zhang Y Matsuda H Ninomiya K Muraoka O Yoshikawa M 《Chemical & pharmaceutical bulletin》2011,59(8):1020-1028
The methanolic extract from the leaves of Salacia chinensis collected in Thailand was found to show a protective effect on D-galactosamine-induced cytotoxicity in primary cultured mouse hepatocytes. From the methanolic extract, eight new glycosides, named foliachinenosides E, F, G, H, and I, and foliasalaciosides J, K and L, were isolated together with 26 known constituents. The structures of new glycosides were determined on the basis of physicochemical and chemical evidence. In addition, the hepatoprotective effects of the isolated compounds on D-galactosamine-induced cytotoxicity were examined. Among them, lignans, eleutheroside E? and 7R,8S-dihydrodehydrodiconiferyl alcohol 4-O-β-D-glucopyranoside, were found to show the protective effects [inhibition (%) 41.4 ± 3.6 (p < 0.01), 45.5 ± 2.7 (p < 0.01) at 100 μM, respectively]. 相似文献
27.
Koji Ishida Yoshiaki Uchida Shuji Ninomiya Masumi Osawa 《Fresenius' Journal of Analytical Chemistry》1990,336(5):419-422
Summary The thin-layer chromatographic behaviour of all the rare earths except Pm on silica gel in aqueous solutions of five alkali metal chlorides has been surveyed. The Rf-values and the logarithms of the separation factors relative to Gd vary in a regular and peculiar way with increasing atomic number, through a reflection of the strong tetrad effect. A discussion concerning the effects on the Rf-values of the solvent cations and the solvent anions, and typical chromatograms for the separations of multi-component mixtures containing adjacent lanthanoids are also presented. 相似文献
28.
T. Noritake M. Aoki S. Towata A. Ninomiya Y. Nakamori S. Orimo 《Applied Physics A: Materials Science & Processing》2006,83(2):277-279
Combination of LiBH4 and LiNH2 by ball milling forms the series of novel complex hydrides Li2BNH6, Li3BN2H8 and Li4BN3H10, depending on the combination ratios. The crystal structure of Li4BN3H10 analyzed by synchrotron X-raydiffraction measurements is determined to be a cubic system (space group: I213) with the lattice constant of a=10.673(2)Å. It should be emphasized that Li4BN3H10 is an ionic crystal which is composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]-. These anions are located in the vertex and face-center of the cubic sub-lattice, and the lithium cation Li+ in the interstitial site between the anions, respectively. The other series of complex hydrides, Li2BNH6 and Li3BN2H8, are also predicted to possess similar structures composed of a lithium cation Li+ and two different kinds of the complex anion [BH4]- and [NH2]-. 相似文献
29.
We derive a theorem of exponential decay of correlation functions at high temperature for a general statistical mechanical system following the approach introduced by L. Gross. The theorem is formulated so as to be useful for locality problems in lattice quantum gravity. 相似文献
30.