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151.
Ikushima Y Hatakeda K Sato O Yokoyama T Arai M 《Angewandte Chemie (International ed. in English)》2001,40(1):210-213
152.
Akira Kono James P. Lin Osamu Nishimura 《Proceedings of the American Mathematical Society》2003,131(10):3289-3295
It is shown that the mod 3 cohomology of a homotopy associative mod 3 -space which is rationally equivalent to the Lie group and which has integral 3-torsion is isomorphic to that of as a Hopf algebra over the mod 3 Steenrod algebra.
153.
We deal with the Hermitian Hurwitz pairs of signature (, s), + s = 5 + 4, | + 1 – s| = 2 + 4m;, m = 0, 1,.... We introduce the Hurwitz twistors for signature (3, 2) and its dual (1, 4) and we indicate the relationship between Hurwitz and Penrose twistors. The signatures (1, 8) and (7, 6) give rise to pseudotwistors and bitwistors, respectively. For pseudotwistors, we prove a counterpart of the Penrose theorem in the local version, on real analytic solutions of the related spinor equations versus harmonic forms, and in the semiglobal version, on holomorphic solutions of those equations versus Dolbeault cohomology groups. We prove an atomization theorem: There exist complex structures on isometric embeddings for the Hermitian Hurwitz pairs so that the embeddings are real parts of holomorphic mappings. 相似文献
154.
Osamu Sugino Ikutaro Hamada Minoru Otani Yoshitada Morikawa Tamio Ikeshoji Yasuharu Okamoto 《Surface science》2007,601(22):5237-5240
First-principles molecular dynamics simulations have been carried out for water in contact with Pt(1 1 1) surface. To apply negative bias potential to the water/Pt interface, excess electrons were added to our slab model using the recently developed computational scheme called “effective screening medium (ESM)”. Water molecules located away from the surface reoriented themselves to screen the electric field, but they responded differently near the surface. Water molecules nearest to the surface, forming a distinct layered structure with the hydrogen atom directed to the surface, increased the density with increasing field. On these bases, we discuss microscopic aspects of the electric double layer. 相似文献
155.
A simple method to produce silver nanoparticles on a glass surface from silver nanolayer deposited by magnetron sputtering and thermal annealed is presented. Localized surface plasmon resonance of nanoparticles shows a red shift depending on the silver nanolayer thickness, the refractive index and the thickness of an ultra-thin silicon compound adsorbed on the surface. A highly enhanced Raman spectrum of the characteristic groups of a silicon compound adsorbed on the nanoparticles surface was obtained. 相似文献
156.
157.
Atula S.D. Sandanayaka Hisahiro Sasabe Toshikazu Takata Osamu Ito 《Journal of Photochemistry and Photobiology, C: Photochemistry Reviews》2010,11(2-3):73-92
The photosensitized electron-transfer processes in the rotaxane hybrids composed with electron-accepting fullerenes and various electron-donors placed in the rotaxanes are revealed with time-resolved fluorescence and absorption spectral methods. Porphyrins are most useful as light-harvesting donors and photosensitizing donors. In addition, aromatic amines and ferrocene act as electron-donor and also hole-shifting reagents in multi-component rotaxanes. In the rotaxanes with spatially placed donor-acceptor molecules, the role of triplet states becomes important compared with the covalently connected donor–acceptor molecular systems, which may be related to the “through-space” and “through-bond” electron transfer, respectively. In the designed multi-component rotaxanes which maintain mechanically or topologically the electron-acceptor, electron-donor, and hole-shifter, the photoinduced electron transfer, hole-shift, electron–hole recombination are established. As a whole, contribution of the triplet excited states is prominent compared with the covalently bonded molecules and supramolecular systems constructed with coordination bonds. 相似文献
158.
We examined the utility of a monolithic capillary column in the analysis of pyridylaminated oligosaccharides. Fluorescence detection and mass spectrometry were used to monitor a series of oligosaccharides. Although the total-ion chromatogram appeared similar to that obtained with fluorescence detection, the sensitivity of this technique was limited, especially in the case of smaller oligosaccharides. This limitation was overcome by applying selected ion current monitoring. Further, the capillary column also exhibited good reproducibility. We showed that the retention times obtained by using the monolithic capillary column could be converted into the standard data to enable comparison of the experimental data with the existing data. Furthermore, our studies revealed an important difference in the separation profile, i.e., the monolithic capillary column could resolve smaller oligosaccharides to a greater extent. 相似文献
159.
160.