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61.
This study presents diffusion experiments of NiAl coupled with pure Ni (Ni/NiAl). The couple produces the Ni3Al-based intermetallic phase ( phase) as an intermediate layer at the interface during diffusion annealing. Analytical electron microscopy is used to examine microstructural features, crystallographic orientation and compositional variations across the interface. Interdiffusivities are measured from the compositional variations. It is shown that the growing behavior of the phase changes between higher and lower annealing temperatures. The growth kinetics of the phase is also discussed. 相似文献
62.
Enantioselective syntheses of two 5, 9E diastereomers (1 and 2) of 223V (3) are described. Neither corresponded on GC-MS and GC-FTIR analyses to alkaloid 223I, previously tentatively proposed to be a 5,8-disubstituted indolizidine of the unusual 5, 9E relative stereochemistry. Synthetic (−)-(5, 9Z)-5-n-propyl-8-n-butylindolizidine (3) corresponds on GC-MS and GC-FTIR analyses to the natural indolizidine 223V found in a pumilio from ‘Split Hill’, Panama. 相似文献
63.
Fujimoto H Pinak M Nemoto T O'Neill P Kume E Saito K Maekawa H 《Journal of computational chemistry》2005,26(8):788-798
Clustered DNA damage sites induced by ionizing radiation have been suggested to have serious consequences to organisms, such as cancer, due to their reduced probability to be repaired by the enzymatic repair machinery of the cell. Although experimental results have revealed that clustered DNA damage sites effectively retard the efficient function of repair enzymes, it remains unclear as to what particular factors influence this retardation. In this study, approaches based on molecular dynamics (MD) simulation have been applied to examine conformational changes and energetic properties of DNA molecules containing clustered damage sites consisting of two lesioned sites, namely 7,8-dihydro-8-oxoguanine (8-oxoG) and apurinic/apyrimidinic (AP) site, located within a few base pairs of each other. After 1 ns of MD simulation, one of the six DNA molecules containing a clustered damage site develops specific characteristic features: sharp bending at the lesioned site and weakening or complete loss of electrostatic interaction energy between 8-oxoG and bases located on the complementary strand. From these results it is suggested that these changes would make it difficult for the repair enzyme to bind to the lesions within the clustered damage site and thereby result in a reduction of its repair capacity. 相似文献
64.
Tetsuhiro Nemoto 《Tetrahedron letters》2006,47(37):6577-6581
A Pd-catalyzed asymmetric allylic alkylation with nitromethane using an aspartic acid-derived P-chirogenic diaminophosphine oxide [(S,RP)-Ph-DIAPHOX] is described. This method was successfully applied to enantioselective synthesis of (R)-preclamol and (R)-baclofen. 相似文献
65.
Yasuo Miyata Dr. Miki Terayama Takeo Minari Dr. Tohru Nishinaga Dr. Takashi Nemoto Dr. Seiji Isoda Prof. Koichi Komatsu Prof. 《化学:亚洲杂志》2007,2(12):1492-1504
Oligo(thienylfuran)s with thiophene rings at both ends ( SOSOSOS , DE‐SOSOS , DH‐SOSOS , DE‐SOSOSOS , and DH‐SOSOSOS ; S and O denote thiophene and furan rings, respectively, DE and DH denote diethyl‐ and dihexyl‐substituted, respectively) were newly synthesized by repetitive Stille coupling reactions. The UV/Vis maximum absorptions of the oligomers, SO , SOSO , SOSOS , SOSOSO , and SOSOSOS , exhibited a clear bathochromic shift with increasing number of heterocycles. The value of the oxidation peak potential (Epa1) determined by cyclic voltammetry decreased with an increase in the number of heterocycles by 0.06–0.08 V per heterocycle. The crystal‐packing structures of DE‐SOSOS and DH‐SOSOS determined by X‐ray crystallography have a herringbone motif and are denser than the reported structures of pentacene and α‐sexithiophene. The morphologies of thin films prepared by vacuum deposition and spin coating were investigated by atomic force microscopy and X‐ray diffraction. Among these films, those of DE‐SOSOS and DH‐SOSOS exhibited highly ordered arrangements. The devices based on vacuum‐deposited and spin‐coated films of DE‐SOSOS and DH‐SOSOS displayed the highest FET mobilities of 10?2–10?3 cm2 V?1 s?1 among the oligomers reported in this study. 相似文献
66.
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68.
Masahide Takahashi Masaru Suzuki Yuya Miyagawa Rie Ihara Yomei Tokuda Toshinobu Yoko Takashi Nemoto Seiji Isoda 《Journal of Sol-Gel Science and Technology》2010,54(3):319-324
Photo-curable vinyl modified silicate-phosphate alternating copolymers were prepared by a direct condensation of organochlorosilane
and organophosphoric acid in a solvent-free condition. The obtained copolymers have complete alternating copolymer structure
of silicate and phosphate unit, where the main oxo chain consist of –(Si–O–P–O)
n
-network. They exhibited an excellent solubility of ionic species such as ionic organic dyes. It was also demonstrated the
photo-reduction of Au+ ions to form Au nano particles for plasmonics applications. Micro patterns were also fabricated by soft lithographic processes.
These results indicate that the photo-curable alternating copolymers are one of promising materials for advanced optical information
processing devices. 相似文献
69.