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61.
62.
Masato Takeuchi Hiromasa Yamagawa Masaya Matsuoka Masakazu Anpo 《Research on Chemical Intermediates》2014,40(1):23-31
A hybrid photocatalyst was prepared from visible light-responsive Pt/WO3 and siliceous mordenite (MOR) zeolite by simple impregnation with an aqueous solution of (NH4)10W12O41·5H2O. Unmodified Pt/WO3 had low photocatalytic activity in gas phase oxidation of acetaldehyde because of its low surface area (3–5 m2/g). In contrast, the Pt/WO3–MOR had higher photocatalytic activity under focused sunlight and Xe lamp irradiation. Pt/WO3–MOR with low WO3 content (<20 wt%) adsorbed sufficient acetaldehyde, but absorption of light in the visible region was low. The optimum zeolite content enhancing the photocatalytic activity of Pt/WO3 was estimated to be 30–50 % (w/w). Adsorption of the gaseous reactants and the efficiency of absorption of incident light are both important aspects of high photocatalytic activity. 相似文献
63.
Yagi H Banerjee D Graham B Huber T Goldfarb D Otting G 《Journal of the American Chemical Society》2011,133(27):10418-10421
Double electron-electron resonance (DEER) distance measurements of a protein complex tagged with two Gd(3+) chelates developed for rigid positioning of the metal ion are shown to deliver outstandingly accurate distance measurements in the 6 nm range. The accuracy was assessed by comparison with modeled distance distributions based on the three-dimensional molecular structures of the protein and the tag and further comparison with paramagnetic NMR data. The close agreement between the predicted and experimentally measured distances opens new possibilities for investigating the structure of biomolecular assemblies. As an example, we show that the dimer interface of rat ERp29 in solution is the same as that determined previously for human ERp29 in the single crystal. 相似文献
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66.
Haruhisa Ueda Masahiro Wakisaka Hiromasa Nagase Takeshi Takaha Shigetaka Okada 《Journal of inclusion phenomena and macrocyclic chemistry》2002,44(1-4):403-405
Cyclomaltooctadecaose(CD18),cyclomaltononadecaose(CD19),cyclomaltoeicosaose(CD20) andcyclomaltoheneicosaose(CD21) are cyclic oligosaccharides composed of 18, 19, 20 and 21 D-glucose units, respectively. This report describes the physicochemical properties of CD18, CD19, CD20 and CD21 in terms of aqueous solubility, surface tension, optical rotation and acid-catalyzed hydrolysis. 相似文献
67.
LiMn2O4 is one of the most promising cathode materials for lithium secondary battery because of natural abundance of manganese in
the crust and its low toxicity to environment. Lithium ion can almost reversibly intercalate into or deintercalate from lithium
manganese spinel oxide LiMn2O4. A part of substitution of manganese with other transition metals brings the improvement of cycle life. We focused on the
local structure of the spinels and considered the effect of the local distortion on the cycle life of the spinel cathodes.
Paper presented at the 8th EuroConference on Ionics, Carvoeiro, Algarve, Portugal, Sept. 16–22, 2001. 相似文献
68.
69.
Tanaka H Mori H Seino H Hidai M Mizobe Y Yoshizawa K 《Journal of the American Chemical Society》2008,130(28):9037-9047
The N-N bond activation of the dinitrogen ligand in the cubane-type mixed-metal sulfido cluster, [(Cp*Ir) 3{Ru(tmeda)(N 2)}(mu 3-S) 4] (tmeda = Me 2NCH 2CH 2NMe 2), is investigated by using DFT calculations at the B3LYP level of theory. The elongated N-N bond distance, red-shifted N-N stretching, and negatively charged N 2 ligand indicate that the dinitrogen is reductively activated by complexation. The degree of the N-N bond activation is classified into the "moderately activated" category, [ Studt, F. ; Tuczek, F. J. Comput. Chem. 2006, 27, 1278 ] as in the Mo-triamidoamine complex that can catalyze N 2 reduction [ Yandulov, D. V. ; Schrock, R. R. Science 2003, 301, 76 ]. Availability of the RuIr 3S 4 cluster as a catalyst for N 2 reduction is discussed by optimizing possible intermediates in a catalytic cycle analogous to that proposed by Yandulov and Schrock. A calculated energy profile of the catalytic cycle demonstrates that the RuIr 3S 4 cluster can transform dinitrogen into ammonia in the presence of lutidinium cation and Cp* 2Co as proton and electron sources, respectively. The RuIr 3S 4 clusters with an NNH x ( x = 1-3) ligand, which are intermediates in the catalytic cycle, have a significantly bent Ru-N-N linkage, although precedent NNH x complexes generally adopt a linear M-N-N array. The unique structures of the nitrogenous ligands in these intermediates are interpreted in terms of the bonding interaction between the hydrogen atom bonded to the N 2 ligand and the adjacent iridium atom in the cuboidal RuIr 3S 4 framework. 相似文献
70.
Dr. Katsuhiko Takeuchi Hiro‐omi Taguchi Ippei Tanigawa Shota Tsujimoto Prof. Tsukasa Matsuo Dr. Hiromasa Tanaka Prof. Kazunari Yoshizawa Prof. Fumiyuki Ozawa 《Angewandte Chemie (International ed. in English)》2016,55(49):15347-15350
The Pt0 complex [Pt(PPh3)(Eind2‐BPEP)] with a pyridine‐based PNP‐pincer‐type phosphaalkene ligand (Eind2‐BPEP) has a highly planar geometry around Pt with ∑(Pt)=358.6°. This coordination geometry is very uncommon for formal d10 complexes, and the Pd and Ni homologues with the same ligands adopt distorted tetrahedral geometries. DFT calculations reveal that both the Pt and Pd complexes are M0 species with nearly ten valence electrons on the metals whereas their atomic orbital occupancies are evidently different from one another. The Pt complex has a higher occupancy of the atomic 6s orbital because of strong s–d hybridization due to relativistic effects, thereby adopting a highly planar geometry reflecting the shape and orientation of the partially unoccupied orbital. 相似文献