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101.
Hitoshi Yoshino Kazuo Shimokoshi Eizo Miyazaki 《Journal of Electron Spectroscopy and Related Phenomena》1985,36(3):269-279
DV-Xα calculations have been applied to various small clusters of rutile-family dioxides (NbO2, MoO2 RuO2). It appears that by taking into consideration the potential due to the atomic charges, the density, the ionization cross sections of the energy levels, and by summing the density of states (DOS) of the two different clusters representing surface structures, computations on even small clusters provide information which compares well with the experimental XPS spectra. 相似文献
102.
The synthesis of CuO---Al2O3---SiO2 glasses by the sol-gel method was investigated and the thermal expansion of bulk glasses was measured. Phase separation was observed in these glasses and apparently consisted of a copper-rich dispersed phase and a network former-rich matrix phase. The low thermal expansion coefficient of these glasses was governed by the matrix phase. 相似文献
103.
Five novel phosphate-type hybrid surfactants, CmF2m+1C6H4CH[OPO2(OC6H5)Na]CnH2n+1 (FmPHnPPhNa: m = 4, 6, 8; n = 3, 5; C6H4 = p-phenylene, C6H5 = phenyl), have been synthesized. When compared with sulfate-type hybrid surfactants, CmF2m+1C6H4CH(OSO3Na)CnH2n+1 (C6H4 = p-phenylene), the new hybrid surfactants are found to have comparable abilities to lower surface tension of water. The critical micelle concentrations of FmPHnPPhNa follow Klevens rule and their occupied areas per molecule increase with increasing m and n. Calcium hydroxyapatite (CaHAp) pellets modified with FmPH3PPhNa gives high hydrophobic and lipophobic surfaces. The hybrid surfactants are expected as new dental reagents for oral hygiene. 相似文献
104.
Semi-Glycinecresol Red (SGCR or H(3)SGCR) was purified by means of chromatography on cellulose and by cation-exchange. A potentiometric, spectrophotometric and ESR study on the complex formation equilibria of several bivalent metal ions with SGCR was performed. The acid-base and metal-ligand stoichiometries were determined, and the formation constants, lambda(max) and absorptivities of the visible-region absorption spectra of the corresponding proton and metal complexes were determined. The copper complexes were examined by ESR spectroscopy. Each metal ion was found to form the 1:1 and 1:2 (metal:ligand) complex species, MSGCR(-) and M(SGCR)(4-)(2), in alkaline solution. However, only Cu(II) was found to form the protonated complexes, CuHSGCR and Cu(HSGCR)(2-)(2), in weakly acidic media. SGCR is suitable as an indicator for Cu(II) in a weakly acidic solution and for Cu(II), Zn(II) and Pb(II) in alkaline solution. 相似文献
105.
(±)-Isoagatholactone and (±)-12α-hydroxyspongia-13(16),14-dien , a fundamental skeleton of spongiadiol and its congeners, have been synthesized from (±)-labda-8(20),13-dien-15-oic acid . 相似文献
106.
Two mechanisms of chloride interference are described. The first arises from coordination of chloride to chromium(III), which can be prevented by addition of a masking agent such as tetraammonium—EDTA, The other is due to chloride salts remaining at the atomization step; this can be prevented by volatilizing the chlorides or converting them to oxides before atomization. 相似文献
107.
108.
7-Azaindole did not react with benzophenone on irradiation. However, irradiation of benzophenone in the presence of 1-acetyl-7-azaindole produced an oxetane by cycloaddition of the ketone to the 7-azaindole 2,3-double bond. The nmr and the mass spectra of the oxetane have also been studied in some detail. 相似文献
109.
Kitajima M Fujii N Yoshino F Sudo H Saito K Aimi N Takayama H 《Chemical & pharmaceutical bulletin》2005,53(10):1355-1358
Two new monoterpene glucosides, demethylsecologanol and 3'-O-glucosylsenburiside II, were isolated from Ophiorrhiza liukiuensis (Rubiaceae) together with 23 known compounds, including camptothecins and beta-carboline-type alkaloids. Their structures were determined by spectroscopic analysis. 相似文献
110.
Hirotatsu Umihara Tomomi Yoshino Jun Shimokawa Masato Kitamura Tohru Fukuyama 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(24):7029-7032
A general synthetic methodology toward the erythrina alkaloids has been developed. Inspired by a proposed biosynthetic mechanism, the medium‐sized chiral biaryl lactam was asymmetrically transformed into the common core A–D rings by a stereospecific singlet oxygen oxidation of the phenol moiety, followed by a transannular aza‐Michael reaction to the dienone functionality. The late‐stage manipulation of the oxidation and oxygenation states of the functional groups on the peripheral moieties enabled the flexible syntheses of the erythrina alkaloids. 相似文献