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991.
This paper deals with graded representations of the symmetric group on the cohomology ring of flags fixed by a unipotent matrix. We consider a combinatorial property, called the “coincidence of dimension” of the graded representations, and give an interpretation in terms of representation theory of the symmetric group in the case where the corresponding partition of the unipotent matrix is a hook or a rectangle. The interpretation is equivalent to a recursive formula of Green polynomials at roots of unity. 相似文献
992.
Genki Yoshikawa Tetsuhiko Miyadera Keiji Ueno Shiro Entani Dong Guo Hiroshi Kondoh Koichiro Saiki 《Surface science》2006,600(12):2518-2522
Molecular orientations of pentacene ultrathin films grown on SiO2 substrates were studied without the influence of the atmosphere by vacuum atomic force microscopy (V-AFM) and near edge X-ray absorption fine structure (NEXAFS). The experimental processes from deposition of pentacene to characterization of films were performed under vacuum condition without exposure to the atmosphere. V-AFM and NEXAFS measurements showed that pentacene molecules tend to grow on SiO2 surface with their molecular long axes perpendicular to the substrate surfaces (standing-mode) irrespective of preparation procedure of SiO2 substrate. 相似文献
993.
We have discriminated individual Ge atoms from the intermixed Ge/Si(1 1 1)-(7 × 7) surface using a non-contact atomic force microscope at a room temperature environment. In fact, Si-Ge (IV-IV) binary system is considered as one of the most difficult systems for atomic discrimination among atoms in the IV group because of the similarities in the electronic and chemical properties. However, in this study, we found one of the most attractive tools to discriminate a specific atom from the others even in the difficult Si-Ge system. Ge atoms are shown as dim spots in comparison to Si atoms with bright spots on the intermixed surface by a weak chemical bonding energy and/or a relaxation effect despite large atomic radius and high spatial position in both variable frequency shift and topographic images. The discrimination of individual atoms with respect to the chemical interaction variation will further provide a chance to manipulate different atomic species and assemble various nanostructures in near future. 相似文献
994.
Shiro Matsuoka Yu Nakatsu K? Takehara Sulistyo Saputro Kazuhisa Yoshimura 《Analytical sciences》2006,22(12):1519-1524
A novel on-line oxidation method of ultra-trace Cr(III) dissolved in natural water has been developed using a flow electrolysis cell. This method was successfully applied to the determination of the total Cr concentration by flow injection-solid phase spectrophotometry using diphenylcarbazide as a coloring agent. With the applied potential of 1.35 V (vs. Ag/AgCl) and the flow rate of 0.80 cm(3) min(-1), Cr(III) was quantitatively oxidized to Cr(VI) at room temperature. The total Cr concentration of sub-microg dm(-3) in 3 - 4 samples could be determined within 1 h using an aqueous sample volume of 7.1 cm(3). The analytical values of the total Cr concentration in natural water were in good agreement with those obtained by ICP-MS. The detection limit of the proposed method was 0.014 microg dm(-3) (3sigma, n = 7). This method could be applied to the specific determination of Cr(III) and Cr(VI) in river water samples. 相似文献
995.
996.
Yong He Jianchun Li Hiroshi Uyama Shiro Kobayashi Yoshio Inoue 《Journal of Polymer Science.Polymer Physics》2001,39(22):2898-2905
The intermolecular hydrogen‐bonding interaction and miscibility between enzymatically prepared novel polyphenols [poly(bisphenol A) and poly(p‐tert‐butyl phenol)] and poly(ε‐caprolactone) (PCL) were investigated as a function of composition by Fourier transform infrared spectroscopy (FTIR) and DSC. The blend films of PCL and polyphenols were prepared by casting polymer solution. The FTIR spectra clearly indicated that PCL and polyphenols interact through strong intermolecular hydrogen bonds formed between the PCL carbonyls and the polyphenol hydroxyl groups. The melting point and degree of crystallinity of the PCL component decreased with an increased polyphenol content. A single glass‐transition temperature was observed for the blend, and its value increased with the content of polyphenol, indicating that PCL and polyphenols are miscible in the amorphous state. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2898–2905, 2001 相似文献
997.
Kenta Fujii Shiro Seki Koji Ohara Yasuo Kameda Hiroyuki Doi Soshi Saito Yasuhiro Umebayashi 《Journal of solution chemistry》2014,43(9-10):1655-1668
Ion-ion interactions or liquid structures in low-viscosity ionic liquid, 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)amide, [C2mIm+][FSA?] were investigated by high-energy X-ray diffraction (HEXRD) experiments and molecular dynamics (MD) simulations. Experimental X-ray structure factor, S exp(q) obtained from the HEXRD was successfully deconvoluted into the intra- and the intermolecular components, S intra exp (q) and S inter exp (q), respectively, by taking into account the population of cis and trans conformers of the FSA anion to give the corresponding radial distribution functions, G intra exp (r) and G inter exp (r), respectively. The G inter exp (r) exhibits the peaks at 3.5, 4.6 and 5.4 Å, which is well represented by theoretical radial distribution function, G inter MD (r) obtained from MD simulations. From the space distribution function, SDF calculated by MD simulations, it was found that static structure (distance and orientation) of the nearest neighbor intermolecular interaction between cation and anion in [C2mIm+][FSA?] is similar to its analogous ionic liquid, [C2mIm+][TFSA?] where TFSA is bis(trifluoromethanesulfonyl)amide. 相似文献
998.
This review describes a study of catalytic functions of water splitting at the surface and hydrogen gas emitting from the bulk of metal–oxide layered materials as well as hydrogen storage materials as its application by means of the ion beam analysis techniques. First are described a microscopic model for water splitting at the oxide surface and mass balance equations for hydrogen atoms in the bulk. The latter is a mathematical expression of a one‐way diffusion model proposed for an anomalous isotope effect in D–H and H–D replacements of both deuterium (D) implanted into perovskite oxide ceramics by protium (H) in H2O vapour and the vise versa. The latter model brings about finding of catalytic functions of water splitting at the surface and hydrogen gas emitting from the bulk. Second, experimental results on the anomalous isotope effect are presented and the D–H replacement rates are described in detail. Subsequently are shown results on H2 gas emission measured with a Bach method, which give a clear evidence for the water splitting and hydrogen gas emitting catalytic functions of the oxide surface. Finally, we present experimental data on the hydrogen absorption and emission characteristics of the metal–oxide layered hydrogen storage materials as an application of the water splitting and hydrogen absorbing catalysts. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
999.
Adenosine 3′,5′-cyclic monophosphorodithioate (cAMPS2), which has two exocyclic sulfurs directly attached to phosphorus, was synthesized from adenosine phosphoramidite by intramolecular cyclization employing the phosphotriester method as a key step. 相似文献
1000.
Inhibition of Heme Uptake in Pseudomonas aeruginosa by its Hemophore (HasAp) Bound to Synthetic Metal Complexes 下载免费PDF全文
Chikako Shirataki Dr. Osami Shoji Mitsuyoshi Terada Prof. Dr. Shin‐ichi Ozaki Dr. Hiroshi Sugimoto Prof. Dr. Yoshitsugu Shiro Prof. Dr. Yoshihito Watanabe 《Angewandte Chemie (International ed. in English)》2014,53(11):2862-2866
The heme acquisition system A protein secreted by Pseudomonas aeruginosa (HasAp) can capture several synthetic metal complexes other than heme. The crystal structures of HasAp harboring synthetic metal complexes revealed only small perturbation of the overall HasAp structure. An inhibitory effect upon heme acquisition by HasAp bearing synthetic metal complexes was examined by monitoring the growth of Pseudomonas aeruginosa PAO1. HasAp bound to iron–phthalocyanine inhibits heme acquisition in the presence of heme‐bound HasAp as an iron source. 相似文献