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161.
162.
Certain amides and thioamides can easily be methylated with diazomethane in the presence of silica gel. 相似文献
163.
Waveguided semiconductor optical switches operated by a carrier-induced change in the refractive-index associated with the plasma dispersion are proposed. InGaAsP/InP four-port switches having two intersecting single-mode channel waveguides are fabricated by selective liquid-phase epitaxy and investigated at 1.5m wavelength. Optical switching is observed as a result of mode interference in the waveguide intersection region. 相似文献
164.
The structures of two host-specific phytotoxic metabolites, AK-toxin I and II, isolated from culture broth of Alternaria kikuchiana Tanaka (the fungus causing black spot disease of Japanese pear) were determined to be the ester consisting of N-acetyl-β-methyl-phenylalanine and 9,10-epoxy-8-hydroxy-9-methyl-2E, 4Z, 6E-decatrienoic acid () and its β-demethyl derivative (). 相似文献
165.
Three-dimensional particle crystals made of dicarboxylic thiolate (MSA)-stabilized gold nanoparticles were formed at an air/water interface. FTIR spectra of this supracrystal showed that three well-resolved peaks existed from 3400 to 3550 cm-1 just falling in a region of OH stretching vibrational mode. Precise analysis showed that all these peaks originated from the water cluster included in the interstice of a particle crystal. 相似文献
166.
Juglomycin A has been synthesized in four steps from 5-methoxy-1-naphthol. 相似文献
167.
Masao Tomoi Noriyuki Yanai Satoshi Shiiki Hiroshi Kakiuchi 《Journal of polymer science. Part A, Polymer chemistry》1984,22(4):911-926
Polymer-supported crown ethers were prepared from chloromethylated or ω-bromoalkylated polystyrene resins and hydroxymethylbenzo-18-crown-6 and 15- or 18-membered monoazacrown ethers. Effects of the cavity size of crown ethers, the degree of crosslinking, the degree of ring substitution, particle size, spacer chains, and solvents on the activity of the polymer-supported crown ethers in the reaction of 1-chloro- or 1-bromo-octane with aqueous NaI or KI were investigated and mechanisms of the reaction were discussed in terms of mass transfer, intraparticle diffusion, and intrinsic reactivity. 相似文献
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170.
Oxidative cleavage reactions of catechol with CuCI to give monoester of cis,cis-muconic acid in pyridine containing alcohol was investigated under various conditions. The same oxidation was carried out also with the systems of KO2/CuCl2 and KOH/CuCl2 in pyridine containing alcohol in the absence of oxygen. Phenol was oxidized with the same oxidizing systems to give the same monoester of muconic acid. 相似文献