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991.
Takashi Hashimoto 《Letters in Mathematical Physics》2010,93(2):157-168
Let Alt n be the vector space of all alternating n × n complex matrices, on which the complex general linear group GL n acts by \({x \mapsto gxg^t}\). The aim of this paper is to show that Pfaffian of a certain matrix whose entries are multiplication operators or derivations acting on polynomials on Alt n provides a generating function for the GL n -invariant differential operators that play an essential role in the skew Capelli identity, with coefficients the Hermite polynomials. 相似文献
992.
993.
Atsushi Ohma Takashi Ichiya Kazuyoshi Fushinobu Ken Okazaki 《Surface science》2010,604(11-12):965-973
Theoretical analysis of ORR on Pt (111) was carried out with the combined technique of DFT calculation and the UBI-QEP method in order to understand the overall ORR pathways, behavior of H2O2 formation, and the impact of trifluoromethane sulfonic acid (CF3SO3H and TfOH) coverage, the alternative material of Nafion®, on the reactivity on the Pt surface. The ORR scheme consisting of elementary reactions was then modeled to determine the dominant path and the limiting step based on their activation energies. The results showed that the dominant ORR path included the H2O2 formation step and OOH formation step was limiting. When TfOH covered the Pt surface, it was revealed that the adsorption energy of an O2 molecule on Pt (111) was decreased due to the lower Fermi level and the d-band center, resulting in decreasing the activation energy of the limiting step. TfOH, however, could suppress the O2 adsorption on the Pt surface. In addition, with the TfOH coverage, it was indicated that the limiting step of ORR was shifted to H2O-production step which was after the H2O2 production, resulting in the enhancement of the H2O2 formation. 相似文献
994.
Sato S Nakamura T Nitobe S Kiba T Hosokawa K Kasajima T Otsuka I Akimoto S Kakuchi T 《The journal of physical chemistry. B》2006,110(43):21444-21449
Dimethylanthracene (DMA), which exhibits almost no self-association in bulk organic solvents, forms a dimer and emits excimer-like fluorescence in a gamma-cyclodextrin nanocavity in a dilute aqueous solution. The 1Bb and 1La electronic transitions of the DMA dimer split by 2230 and 344 cm(-1), respectively, in a fluorescence excitation spectrum obtained with the excimer-like emission. From these energy splits, the structure of dimer in relation to a dielectric constant inside gamma-CD was discussed on the basis of atom-atom Lennard-Jones potential calculations including Coulombic interactions. Excitation relaxations of DMA in the presence of alpha-, beta-, and gamma-CDs in aqueous solutions were investigated by time-resolved fluorescence. The results suggest that both the hydrated and anhydrated species exist in the alpha- and gamma-CD complexes, while only the anhydrated species exists in the beta-CD complex. 相似文献
995.
Matsuya Y Kawaguchi T Ishihara K Ahmed K Zhao QL Kondo T Nemoto H 《Organic letters》2006,8(20):4609-4612
Hybrid compounds of macrosphelides and epothilones, both of which are natural macrolides having a 16-membered skeleton, were designed and synthesized using a ring-closing metathesis (RCM) strategy. Some of these hybrids were found to exhibit notable apoptosis-inducing activity against human lymphoma cells with higher potency than parent natural macrosphelides, and to be a promising lead compound for development of a new antitumor agent. 相似文献
996.
Supramolecular chiral columnar liquid crystals have been formed through one-dimensional self-assembly of pyrene-containing oligopeptides. Supramolecular chirality is further tuned by cooperation of intermolecular hydrogen bonding and electron donor-acceptor interactions. [reaction: see text] 相似文献
997.
Takashi Noiri 《Rendiconti del Circolo Matematico di Palermo》2006,55(1):29-42
Cammaroto and Noiri [14] introduced a separation axiom calledm-R
0 in anm-space (X, m). In this paper, we introduce the notion ofm-R
1 spaces and offer many characterizations ofm-R
0 (resp.m-R
1) spaces which enable us to obtain unified characterizations of separation axiomsR
0, semi-R
0, pre-R
0,α-R
0,δ-semiR
0, (δ, p)-R
0 (resp.R
1, semi-R
1, pre-R
1,α-R
1,δ-semiR
1, (δ, p)-R
1). 相似文献
998.
Summary Members of the vascular endothelial growth factor (VEGF) family are crucial regulators of neovascularization and are classified as cystine knot growth factors that specifically bind cellular receptor tyrosine kinases VEGFR-1, VEGFR-2, and VEGFR-3 with high but variable affinity and selectivity. The VEGF family has recently been expanded and currently comprises seven members: VEGF-A, VEGF-B, placenta growth factor (PlGF), VEGF-C, VEGF-D, viral VEGF (also known as VEGF-E), and snake venom VEGF (also known as VEGF-F). Although all members are structurally homologous, there is molecular diversity among the subtypes, and several isoforms, such as VEGF-A, VEGF-B, and PlGF, are generated by alternative exon splicing. These splicing isoforms exhibit differing properties, particularly in binding to co-receptor neuropilins and heparin. VEGF family proteins play multiple physiological roles, such as angiogenesis and lymphangiogenesis, while exogenous members (viral and snake venom VEGFs) display activities that are unique in physiology and function. This review will highlight the molecular and functional diversity of VEGF family proteins. 相似文献
999.
We study the Falk model system describing martensitic phase transitions in shape memory alloys. Its physically closed stationary state is formulated as a nonlinear eigenvalue problem with a non‐local term. Then, some results on existence, stability, and bifurcation of the solution are proven. In particular, we prove the existence of dynamically stable nontrivial stationary solutions. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
1000.
Teruo Kitamura Akio Mukoh Masato Isogai Takashi Inukai Kenji Furukawa Kanetsugu Terashima 《Molecular Crystals and Liquid Crystals》2013,570(2-4):167-173
A series of chiral benzylidene-aniline compounds, 4-alkoxybenzylidene 4′-(2-methylbutyloxycarbonyl)anilines, have been synthesized and their mesomorphic properties are examined. They showed a monotropic chiral smectic C phase in conjunction with enantiotropic smectic A phase, and their chiral smectic C—smectic A phase transition temperatures are around room temperatures. Their spontaneous polarization values are moderately higher than those of DOBAMBC “4-decyloxybenzylidene 4′-amino-(2-methylbutyl)cinnamate”. 相似文献