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181.
182.
The 13C FT NMR spectra of β-D -glucopyranosides (including their tetraacetates) of several secondary allylic and benzylic alcohols were compared with those of methyl β-D -glucopyranoside and the corresponding parent alcohols. The characeristic glucosidation shifts observed for these alcohols may be applicable to the determination of the absolute configuration of the hydroxy group in these alcohols.  相似文献   
183.
The structures of (+)rugulosin, (?)luteoskyrin and (?)rubroskyrin have been reexamined by NMR and new structures 18, 19 and 20 proposed respectively. Their absolute structures were established on the basis of the X-ray analysis of (+)dibromodehydrotetrahydrorugulosin (27). The minor analogous metabolites, (?)4a-oxyluteoskyrin (31) of P. islandicum and (+)4a-oxyrugulosin (32) of P. brunneum, have been formulated. On oxidation of (?)luteoskyrin and (+)rugulosin with pertrifluoroacetic acid (?)4a,4a′-dioxyluteoskyrin (33) and (+>4a,4a′-dioxyrugulosin (34) were formed, while with MnO2 (+)4a,4a′-dehydrorugulosin (35) was obtained. The structures of lumiluteoskyrin (37), and deoxylumiluteoskyrin (38), photooxidation products of luteoskyrin and deoxyluteoskyrin, respectively, have been elucidated.  相似文献   
184.
185.
This study examined the structural properties of ZnO nanorods grown on Ti-buffer layers with different surface roughnesses of 1.5 and 4.0 nm. Vertically aligned ZnO nanorods were synthesized on Al2O3 substrates with a Ti-buffer layer by metal-organic chemical vapor deposition. X-ray diffraction revealed the ZnO nanorods grown on a smooth surface to have higher quality and better alignment in the ab-plane than those grown on the rough surface. Field-emission transmission electron microscopy (FE-TEM) measurements revealed a disordered layer at the ZnO/Ti interface. FE-TEM demonstrated that the Ti-buffer layer contained a mixture of ordered and amorphous phases. Energy dispersive spectroscopy (EDS) analysis revealed the Ti-buffer layers to be entirely oxides.  相似文献   
186.
187.
CD43 (sialophorin, leukosialin) is a heavily sialylated surface protein expressed on most leukocytes and platelets including T cells. Although CD43 antigen is known to have multiple and complex structure, exact function of CD43 in each cell type is not completely understood. Here we evaluated the role of CD43 in Fas (CD95)-induced cell death in human T lymphoblastoid cell line, Jurkat. Crosslinking CD43 antigen by K06 mAb increased the Fas-mediated Jurkat cell apoptosis and the augmentation was inhibited by treatment with caspase inhibitors. Further, CD43 signaling of Jurkat cells induced Fas oligomerization on the cell surfaces implying that CD43 ligation have effects on early stage of Fas-induced T cell death. These also suggest that CD43 might play an important role in contraction of the immune response by promotion of Fas-induced apoptosis in human T cells.  相似文献   
188.
We have developed an approach to generate micropatterns of anisotropic organic materials which exploits the self-organization, driven by pi-stacking and hydrophobic interactions, of an ionic perylenebis(dicarboximide) in aqueous solutions.  相似文献   
189.
190.
The dye coloring process on a nano-porous TiO2 thin film for DSSCs was studied using an electrostatic spraying (ESS) method. In this study, dye coating experiments were performed using homemade ESS equipment. The coating patterns on the TiO2 thin film are changed by adjusting the applied voltages of the ESS system. The geometry of the coating patterns is observed by a charge-coupled device (CCD) camera. The TiO2 thin film is fabricated by controlling the electric field which allows a uniform color distribution to be obtained with a high dyeing capacity. The colored TiO2 thin films are compared with those obtained using a conventional immersed dye solution by means of an UV–vis spectrometer. The performance of this novel coloring process was confirmed by measuring I–V curve characteristics.  相似文献   
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