The charge-discharge behaviors of natural graphite in propylene carbonate (PC):dimethyl carbonate (DMC) mixed solutions were investigated after a solid electrolyte interface (SEI) was formed in an ethylene carbonate (EC)-based electrolyte. Electrolytes consisting of LiClO 4 /PC and PC:DMC (1:1 by vol) caused a continuous decomposition of solvents, which led to the exfoliation of graphite. On the other hand, LiClO 4 /PC:DMC (1:7 by vol) showed successful charge-discharge curves without the exfoliation of graphite. These results indicate that the mixing ratio of PC:DMC plays an important role in suppression of the exfoliation of a graphite electrode. Raman spectra of the electrolytes show that the solvation numbers of PC molecules per lithium ion differ drastically in PC:DMC (1:1 by vol) and PC:DMC (1:7 by vol) due to the selective solvation of PC molecules. These results indicate that the solvation number of PC molecules per lithium ion is an important factor in determining the charge-discharge behavior of graphite in PC-based electrolyte.

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The Structure of Nanaomycin AResults of the elementary analysis and the mass spectral analysis (M+ m/e 302.084) gave the molecular formula of C16H14O6. The pKa' values of nanaomycin A (5.9 and 10.9 in 60% ethanol) suggested the presence of a phenolic hydroxyl group and a carboxyl group. This was confirmed by formation of a monoacetate (II), vKBrmax 1765, 1700 and 1670 cm -1, and of a methyl ester (III), vmas 1730, 1645 and 1615 cm-1. The infrared absorption at 1640 and 1615 cm-1 and the ultraviolet spectra [290%MeOHmax nm(e): 250(9850), 273(12,200) and 423(4040);M0.1N NaOH-90% MeOH nm(e): 279(12,700) and 528(5170)] of nanaomycin A indicated the presence of quinone carbonyl groups, one of which was hydrogen-bonded to the phenolic hydroxyl group.3) The absorption

A new form of microchip isoelectric focusing that allows efficient coupling with pretreatment processes is reported. The sample is conveyed in a carrier ampholyte solution to the separation channel that is connected at both ends by two V-shaped lead channels, which supply electrode solutions to the connection point and complete the electrical connection to off-chip electrodes. The relatively high electric conductivity of the electrode solutions compared with that of the pH gradient enables focusing with a 2% loss of applied voltage at the electrodes using the lead channels. A glass microchip was constructed specifically for this configuration. The channel wall was coated with polydimethylacrylamide, and the IEF chip was operated in a chip holder equipped with on-chip connector valves. A plug of fluorescence-labeled peptide p I markers with p I values ranging from 3.64 to 9.56 with carrier ampholyte solution (pH 3-10) was introduced into the separation channel. When the plug reached the channel segment (24 mm in length) between the connection points with the electrolyte lead channels, isoelectric focusing was started after filling the lead channels with electrolyte solutions. The peptide markers were observed using scanning fluorescence detection. The entire range of the pH gradient was established in the segment after approximately 2 min. Isoelectric focusing of three consecutively injected sample plugs containing different p I markers was demonstrated.