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61.
A first synthesis of an asymmetric and amphiphilic β-substituted porphyrin is reported. The porphyrin can be integrated into various types of nanostructures with the amphiphilic characters in hydrophilic solvents. The one-dimensional integration may induce a magnetic interaction between the central metals. 相似文献
62.
Sang-Woo Kim Teruhisa Kotani Masaya Ueda Shizuo Fujita Shigeo Fujita 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):601
Selective formation of ZnO nanodots grown by metalorganic chemical vapor deposition (MOCVD) was achieved on focused-ion beam (FIB)-nanopatterned SiO2 and Si substrates. The selective formation characteristics, dimension, and density of ZnO nanodots on FIB-nanopatterned substrates strongly depended on the FIB-patterning and MOCVD-growth conditions. The mechanism of the selective formation of ZnO nanodots on FIB-nanopatterned SiO2 substrates is attributed to a surfactant effect of the implanted Ga which leads to the formation of the preferred nucleation sites for the growth of ZnO nanodots, while that of ZnO nanodots on nanopatterned Si substrates is mainly considered in terms of the generation of surface atomic steps and kinks, which are created by Ga+ ion sputtering, on the patterned Si areas. 相似文献
63.
64.
The energy spectrum and α-spectroscopic factors of40Ca are calculated by using an α+36Ar orthogonality condition model. Overall agreement is obtained with the experimental data. The model successfully produces the parity-doubletK π=O + and O? α+36Ar cluster bands. It is shown that the coexistence and interference of α-cluster states and shell-model states are indispensable to understand the structure of40Ca. 相似文献
65.
66.
Oligosaccharides in therapeutic recombinant antibodies play important roles in regulation of various biological functions. To monitor the glycosylation profiles of antibody pharmaceuticals in the manufacturing process, a highly sensitive and specific method is required. We extended partial-filling techniques using lectins and exoglycosidases in capillary electrophoresis for the characterization of 8-aminopylene-1,3,6-trisulfonic acid labeled N-linked oligosaccharides derived from the therapeutic antibody rituximab. In the lectin-filling method, Galb1–4GlcNAc-specific Erythrina cristagali agglutinin, a1, 6-linked Fuc-specific Aleuria aurantia lectin and Neu5Aca2–3Gal-specific Maackia amurensis lectin were used. The oligosaccharides migrated through the lectin plug during separation; the changes in separation profiles were observed according to the interaction with the lectins. The glycosidase-filling method allowed rapid digestion as suggested by the electropherograms. Partial-filling CE methods can avoid tedious hands-on procedures such as overnight incubation and optimization reaction condition with lectins and exoglycosidases. Combination of these partial-filling capillary electrophoresis methods makes the characterization of oligosaccharide profiles of therapeutic antibodies easier and faster. 相似文献
67.
In 3-ethoxycarbonyl-2,4-dienal compounds, a thermal [1,5]-H shift of aldehyde hydrogen easily proceeded to produce the corresponding vinyl ketenes due to the remarkable substituent effect caused by the C3 ester group. The produced ketenes were captured by an alcohol and olefins to afford the corresponding esters and four-membered ring compounds, respectively. 相似文献
68.
Hiroshi Mukai Shoji Miyazaki Shigeo Umetani Sorin Kihara Masakazu Matsui 《Analytica chimica acta》1989
Solvent extraction of europium (III), zinc (II) cobalt (II) with α-acyl-d-camphor and optically active isomers of quinine and quinidine was studied in order to obtain information on chirality recognition based on adduct formation between a chiral metal chelate and optically active isomers. It was possible to differentiate clearly between the adduct formation of quinine and that of quinidine in the synergic extraction of cobalt and europium with 3-heptafluorobutyryl- d-camphor and cobalt with 3-trifluoroacetyl-d-camphor. 相似文献
69.
Shigeo Tohyama 《Tetrahedron letters》2005,46(32):5263-5264
A new total synthesis of calothrixin B is described. The key step is an allene-mediated electrocyclic reaction involving the indole 2,3-bond for the construction of a suitable 4-oxygenated 2,3,4-trisubstituted carbazole ring system. 相似文献
70.