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171.
Sho Shirakata Masahiko Kondow Takeshi Kitatani 《Journal of Physics and Chemistry of Solids》2005,66(11):2119-2122
Polarized Raman spectra have been studied on the lattice-matched Ga0.94In0.06N0.025As0.975 epitaxial layers grown on (100) GaAs by molecular beam epitaxy. Polarization dependence of TO and LO phonon modes has been examined. The N-related local vibrational mode (LVM) in GaInNAs has been studied with emphasis on the light polarization and the effect of the thermal annealing. The thermal annealing-induced change of the N-related LVM in GaInNAs is discussed in terms of the local atomic arrangement around N atoms. 相似文献
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173.
Kobayashi K Tonegawa N Fujii S Hikida J Nozoye H Tsutsui K Wada Y Chikira M Haga MA 《Langmuir : the ACS journal of surfaces and colloids》2008,24(22):13203-13211
A novel Ru complex bearing both an acridine group and anchoring phosphonate groups was immobilized on a surface in order to capture double-stranded DNAs (dsDNAs) from solution. At low surface coverage, the atomic force microscopy (AFM) image revealed the "molecular dot" morphology with the height of the Ru complex ( approximately 2.5 nm) on a mica surface, indicating that four phosphonate anchor groups keep the Ru complex in an upright orientation on the surface. Using a dynamic molecular combing method, the DNA capture efficiency of the Ru complex on a mica surface was examined in terms of the effects of the number of molecular dots and surface hydrophobicity. The immobilized surface could capture DNAs; however, the optimal number of molecular dots on the surface as well as the optimal pull-up speed exist to obtain the extended dsDNAs on the surface. Applying this optimal condition to a Au-patterned Si/SiO 2 (Au/SiO 2) surface, the Au electrode was selectively covered with the Ru complex by orthogonal self-assembly of 4-mercaptbutylphosphonic acid (MBPA), followed by the formation of a Zr (4+)-phosphonate layer and the Ru complex. At the same time, the remaining SiO 2 surface was covered with octylphosphonic acid (OPA) by self-assembly. The selective immobilization of the Ru complex only on the Au electrode was identified by time-of-flight secondary-ion mass spectrometry (TOF-SIMS) imaging on the chemically modified Au/SiO 2 surface. The construction of DNA nanowires on the Au/SiO 2 patterned surface was accomplished by the molecular combing method of the selective immobilized Ru complex on Au electrodes. These interconnected nanowires between Au electrodes were used as a scaffold for the modification of Pd nanoparticles on the DNA. Furthermore, Cu metallization was achieved by electroless plating of Cu metal on a priming of Pd nanoparticles on the Pd-covered DNA nanowires. The resulting Cu nanowires showed a metallic behavior with relatively high resistance. 相似文献
174.
A partially benzylated derivative of anhydro-d-altro-heptulose found in Coriaria japonica A, which is a synthetically useful unit, was successfully synthesized from a d-mannose derivative by a novel synthetic approach involving the intramolecular O-ketopyranosylation reaction developed by us. This synthetic approach was also applicable to the preparation of its four analogs. 相似文献
175.
Ishii S Ishikawa S Mizuno N Matsuoka K Honda C Endo K 《Journal of colloid and interface science》2008,317(1):115-120
Shape transitions were examined with regard to the solubilization of the poorly water-soluble drug indomethacin (IMC) in the nonionic surfactants heptaethylene oxide tetradecyl (C14E7) and hexadecyl (C16E7) ethers by means of a dynamic light scattering technique. The cloud points of the pure C14E7 and C16E7 micelles ranged from 58 to 62 degrees C and from 52.1 to 55.6 degrees C, respectively, at surfactant concentrations of 1 to 10 mM. The cloud points of IMC-solubilized micelles increased by approximately 1 to 5 degrees . The sizes of the pure C14E7 micelles were 4 to 14 nm at 20 to 40 degrees C at a concentration of 2 to 20 mM. The apparent hydrodynamic radius (R happ) of pure C16E7 micelles varied with temperature and concentration. C16E7 surfactant formed small spherical micelles at 20 and 25 degrees C at concentrations below 5 mM; the size of the micelles was approximately 5 nm. On the other hand, from 30 to 40 degrees C and at a higher concentration, C16E7 formed elongated cylindrical micelles, and these elongated micelles entangled or overlapped each other. The R happ of the IMC-solubilized C14E7 micelles at 20 to 40 degrees C and of C16E7 micelles at 20 degrees C increased compared to that of pure micelles. On the other hand, the cylindrical micelles of C16E7 decreased in size and turned into spherical ones because of the hydrophobicity between the micelles caused by solubilization of IMC. This phenomenon was confirmed by transmission electron microscope (TEM) images. 相似文献
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178.
Ueda S Ohno K Noguchi Y Ishii S Onoe J 《The journal of physical chemistry. B》2006,110(45):22374-22381
Fullerene polymers made of C(60) are systematically investigated by means of a first-principles pseudopotential approach within the local density approximation of the density functional theory. We assume 10 different structures of fullerene polymers. The first three are C(60) polymer networks cross-linked by [2+2] cycloadditional four-membered rings, and the other seven are composed of peanut-shaped fused C(60) polymer chains cross-linked by either seven-membered rings or eight-membered rings. Owing to the overlap of wave functions as well as the hybrid networks of sp(2)-like (3-fold coordinated) and sp(3)-like (4-fold coordinated) carbon atoms, the electronic structure is considerably different from each other. We find that the resulting electronic structure is either semiconductor or semimetal depending on the spatial dimensionality of materials. 相似文献
179.
Sho Suda 《Journal of Combinatorial Theory, Series A》2012,119(1):117-134
We define new parameters, a zero interval and a dual zero interval, of subsets in P- or Q-polynomial association schemes. A zero interval of a subset in a P-polynomial association scheme is a successive interval index for which the inner distribution vanishes, and a dual zero interval of a subset in a Q-polynomial association scheme is a successive interval index for which the dual inner distribution vanishes. We derive bounds of the lengths of a zero interval and a dual zero interval using the degree and dual degree respectively, and show that a subset in a P-polynomial association scheme (resp. a Q-polynomial association scheme) having a large length of a zero interval (resp. a dual zero interval) induces a completely regular code (resp. a Q-polynomial association scheme). Moreover, we consider the spherical analogue of a dual zero interval. 相似文献
180.
We introduce a class of regular unit Hadamard matrices whose entries consist of two complex numbers and their conjugates for a total of four complex numbers. We then show that these matrices are contained in the Bose–Mesner algebra of an association scheme arising from skew Paley matrices. 相似文献