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101.
102.
Quanli Hu Hiroshi Suzuki Hiroshi Araki Wen Yang Tetsuji Noda 《Superlattices and Microstructures》2002,32(4-6)
The isotopically enriched silicon (28Si) nanowires have been fabricated by using the floating-zone (FZ) melting vapour method. The growth of the nanowires was performed in the top area, 1.52 cm from the floating melting zone (2 mm width) of a raw material bar under a flow of Ar gas. Field emission scanning electron microscopy and transmission electron microscopy analyses revealed that the nanowires of isotopically enriched 28Si crystalline had diameters ranging from 2050 nm and lengths of several hundreds of micrometres. The special structure of the tip of the isotopically enriched 28Si nanowires was observed. 相似文献
103.
The trans-cis photoisomerization behavior of azobenzene-bipyridine ligand (dmpAB) was synchronized with coordination of the bipyridine moiety to copper. The coordination reaction can be reversibly controlled with reversible redox reaction of copper, to afford [Cu(dmpAB)(2)](+) in Cu(I) state and free dmpAB in Cu(II) state. UV irradiations to Cu(I) and Cu(II) samples form trans-rich and cis-rich compositions, respectively. The results enable us to control the trans-cis isomerization reversibly through Cu(II)/Cu(I) redox and a single UV light. 相似文献
104.
Yamayoshi A Iwase R Yamaoka T Murakami A 《Chemical communications (Cambridge, England)》2003,(12):1370-1371
Hairpin type psoralen-cojugated oligonucleotides cross-linked with RNA when they hybridized with a perfectly complementary RNA. 相似文献
105.
One of the well-known convergence acceleration methods, the -algorithm is investigated from the viewpoint of the Toda molecule equation. It is shown that the error caused by the algorithm is evaluated by means of solutions for the equation. The acceleration algorithm based on the discrete Toda molecule equation is also presented.
106.
Omar Foda Kenji Iohara Michio Jimbo Rinat Kedem Tetsuji Miwa Hong Yan 《Letters in Mathematical Physics》1994,32(3):259-268
An elliptic deformation of $\widehat{s1}_2 $ is proposed. Our presentation of the algebra is based on the relationRLL = LLR *, whereR andR * are eight-vertexR-matrices with the elliptic moduli chosen differently. In the trigonometric limit, this algebra reduces to a quotient of that proposed by Reshetikhin and Semenov-Tian-Shansky. Conjectures concerning highest-weight modules and vertex operators are formulated, and the physical interpretation ofR * is discussed. 相似文献
107.
A novel method for the synthesis of N-alkyl-3-acyl-4-alkoxycarbonylmethylpyrrolidine-2,5-diones (3) was accomplished. α-Oxoketene O,N-acetals (1) reacted with maleic anhydride (2) at 80–110 °C for 5 h without solvent to give 3 in moderate to good yield (36–74%). Single X-ray crystallographic analysis showed that the two substituents on C-3 and C-4 were trans. 相似文献
108.
The hydrolytic activity of phosphatidylinositol (PI)-specific phospholipase C (PI-PLC) from Bacillus thuringiensis was studied in detail toward mixed liposomes consisting of PI and one of other phospholipids and cholesterol. Among PI-liposomes, small unilamellar vesicles (SUV) were the most sensitive to PI-PLC; the enzymatic hydrolysis of PI in SUV was not less than 10-fold that in large unilamellar vesicles (LUV) or in multilamellar vesicles (MLV). Thus, in a survey of the effects of coexisting lipids on PI-PLC activity, PI-SUV was used. Phosphatidylcholine (PC) was stimulative for the enzyme activity toward PI-SUV at any molar ratio of PC to PI. Also, the effects of the addition of sphingomyelin (SM), phosphatidylethanolamine (PE) and cholesterol on the enzymatic hydrolysis of PI were studied in detail on the basis of concentration of total lipids or PI. 相似文献
109.
A convergent synthetic route to the (E)FGH ring system 4 of ciguatoxins, the causative toxins for ciguatera fish poisoning, has been developed. The synthesis features convergent coupling to form dioxane acetal, regioselective acetal cleavage by diethylaluminum phenylthiolate or diisobutylaluminum phenylselenolate followed by intramolecular radical cyclization to construct the oxepane ring G, and a ring-closing metathesis reaction to form the hexahydrooxonine ring F. The hexahydrooxonine ring F of tetracyclic model system 4 existed as a 5:1 equilibrium mixture of two conformers (UP and DOWN conformers), with the UP one predominating. This is the first illustration that reproduces the preference for the UP conformer over the DOWN one, which preference was observed for natural ciguatoxins. 相似文献
110.
1-Ehtoxycarbonyl-1, 2-dihydroquinoline-2-phosphonates () were treated with n-butyllithium followed by alkyl halides to afford the corresponding 4-alkylated phosphonates () with complete regioselectivity in 67–97% yields. The phosphonates () were converted to 4-alkylquinolines () in ca. 50% yields by treatment with sodium iodide in HMPA or by alkaline hydrolysis in aqueous ethanol. 相似文献