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31.
32.
We have developed a Cd2+ fluorescent chemosensor with high selectivity as well as sensitivity by tethering a 4,7-bis(2-hydroxyethyl)-9-hydroxy-1,4,7-triazanonyl chelator to anthracene. This sensor features the ability to discriminate Cd2+ from Zn2+ to a high degree (KdZn/KdCd = 560) in a pH 7.2 buffer. 相似文献
33.
General acid‐catalyzed reaction can be enhanced by the addition of base. Self‐catalyzed esterification of benzoic acid and octan‐1‐ol was enhanced by the addition of certain base such as imidazole. The rate of the esterification was accelerated as the concentration of imidazole increased. Trans‐esterification of 4‐nitrophenyl acetate was promoted in chloroform by the mixture of benzoic acid and imidazole, but not by benzoic acid or imidazole alone. 相似文献
34.
Archiv der Mathematik - Lin and Xi introduced Auslander–Dlab–Ringel (ADR) algebras of semilocal modules as a generalization of original ADR algebras and showed that they are... 相似文献
35.
Kazuto Ohashi Kaname Hashizaki Hiroyuki Taguchi 《Journal of Dispersion Science and Technology》2013,34(5):720-724
The effects of inorganic salts on micellization and solubilization of prednisolone in aqueous solution of poly(ethylene oxide)/poly(propylene oxide)/poly(ethylene oxide) triblock copolymer (Pluronic P85) were studied. The effect of inorganic salts on decrease in the cloud point and the critical micelle concentration (cmc) of Pluronic P85 was the order of Na2HPO4 > NaH2PO4 > NaCl > NaBr. Moreover, it was found that Pluronic P85 forms two kinds of micelles: monomolecular micelles and polymolecular micelles. The polymolecular micelle increased with increasing amount of added inorganic salts. Moreover, solubilization behavior is explained from the standpoint of salting out for prednisolone and association characteristics of Pluronic P85. 相似文献
36.
[4+1] Cycloaddition reaction between isocyanides and N-acylimine derivatives generated from N-acyl N,O-acetals acting as isocyanophiles has been developed. These reactions proceeded smoothly and cleanly to afford the corresponding 5-aminooxazoles in high yields. This reaction was extended to the syntheses of 5-aminothiazoles by using N-thioacyl N,O-acetals. A wide range of N-acyl N,O-acetals, N-thioacyl N,O-acetals, and isocyanides were found to be applicable to this reaction. 相似文献
37.
Kaname Tsutsumiuchi Keigo Aoi Masahiko Okada 《Macromolecular rapid communications》1995,16(10):749-755
A novel glycopeptide-containing block copolymer, poly[O-(tetra-O-acetyl-β-D -glucopyranosyl)-L -serine]-block-poly(2-methyl-2-oxazoline) ( 5 ), was synthesized by mutual termination of living polymerizations of a sugar-substituted α-amino acid N-carboxyanhydride (NCA) ( 1 ) and 2-methyl-2-oxazoline ( 3 ). 5 was deacetylated to provide the glycopeptide-polyoxazoline block copolymer, poly[O-(β-D -glucopyranosyl)-L -serine]-block-poly(2-methyl-2-oxazoline) ( 6 ). 相似文献
38.
Gold nanoparticles located at the interface of anatase/rutile TiO2 particles as active plasmonic photocatalysts for aerobic oxidation 总被引:1,自引:0,他引:1
Tsukamoto D Shiraishi Y Sugano Y Ichikawa S Tanaka S Hirai T 《Journal of the American Chemical Society》2012,134(14):6309-6315
Visible-light irradiation (λ > 450 nm) of gold nanoparticles loaded on a mixture of anatase/rutile TiO(2) particles (Degussa, P25) promotes efficient aerobic oxidation at room temperature. The photocatalytic activity critically depends on the catalyst architecture: Au particles with <5 nm diameter located at the interface of anatase/rutile TiO(2) particles behave as the active sites for reaction. This photocatalysis is promoted via plasmon activation of the Au particles by visible light followed by consecutive electron transfer in the Au/rutile/anatase contact site. The activated Au particles transfer their conduction electrons to rutile and then to adjacent anatase TiO(2). This catalyzes the oxidation of substrates by the positively charged Au particles along with reduction of O(2) by the conduction band electrons on the surface of anatase TiO(2). This plasmonic photocatalysis is successfully promoted by sunlight exposure and enables efficient and selective aerobic oxidation of alcohols at ambient temperature. 相似文献
39.
A solid-supported acidic oxazolium perchlorate was investigated as a heterogeneous catalyst in N-glycosylation reactions using silylated modified pyrimidines and an acylated ribose or glucose to afford the corresponding pyrimidine nucleosides. This salt is a nonhygroscopic and stable powder whose activity is comparable to that of 2-methyl-5-phenylbenzoxazolium perchlorate. A reaction with this polymer catalyst can be conducted on a gram scale. Reusability of the solid-supported catalyst was also investigated. 相似文献
40.
Bankwitz characterized the alternating diagrams of the trivialknot. A non-alternating diagram is called almost alternatingif one crossing change makes the diagram alternating. We characterizethe almost alternating diagrams of the trivial knot. As a corollary,we determine the unknotting number one alternating knots withthe property that the unknotting operation can be done on itsalternating diagram. Received July 3, 2007. Revised September 29, 2008. 相似文献