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Wakabayashi Y 《J Phys Condens Matter》2011,23(48):483001
The atomic arrangement in a solid contains a great amount of information, and observation of its structure is essential for understanding the electronic and magnetic properties of transition metal oxides at a microscopic level. Increasing interest in the surfaces and interfaces of oxide systems, which is partly driven by the anticipation of device applications, enhances the importance of structural studies of the near-surface region. We review various types of structural studies with x-ray scattering on the near-surface region of metal oxides-from thick films to surfaces-in order to clarify the structural effects on their electronic properties. 相似文献
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Yasuhiro Kajihara Hironobu Hashimoto Hisashi Kodama Tomio Wakabayashi Ken-ichi Sato 《Journal of carbohydrate chemistry》2013,32(7):991-995
Abstract Specific inhibitors of glycosyltransferases have become of interest1 not only for investigation of carbohydrate-participating cell-surface phenomena but also for practical use such as chemotherapeutic reagents. Glycosyltransferases catalyze the transfer of glycosyl moieties from nucleotide donors to oligosaccharide acceptors. Therefore, two kinds of substrate-analog inhibitors are possible. The donor analogs have been rather well studied, but are not specific. On the other hand, glycosyltransferases have in general smct acceptor specifkity. Recently, acceptor analogs which inhibit the corresponding glycosyltransferases were reported2-5 and as expected were acceptor-specific inhibitors. 相似文献
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Atsunori Ono Yohei Takahashi Sumio Kato Masataka Ogasawara Takashi Wakabayashi Yuunosuke Nakahara Shinichi Nakata 《Research on Chemical Intermediates》2011,37(9):1225-1230
A10(PO4)6(OH)2 (A = Ca and Sr)-supported Pt catalysts were prepared and their catalytic activity in NO reduction were investigated. The Sr10(PO4)6(OH)2-supported catalyst had high catalytic activity in the C3H6?CNO?CO2 reaction; the activity was higher than that of the ??-Al2O3-supported catalyst at 300 °C. The basicity of the apatite supports would affect the chemical state of Pt on catalyst, resulting in promotion of NO reduction. 相似文献
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Oshima S Kashihara I Moritani K Inui N Mochiji K 《Rapid communications in mass spectrometry : RCM》2011,25(8):1070-1074
In secondary ion mass spectrometry (SIMS) of organic substances, the dissociation of the sample molecules is crucial. We have developed SIMS equipment capable of bombardment, where the primary ions are argon cluster ions with kinetic energy per atom controllable down to 1 eV. We previously reported the detection of intact ions of insulin and cytochrome C using this equipment. In this paper, we present a detailed characterization of the emission of secondary ions from insulin, focusing on the difference in secondary ion yield between intact ions and fragment ions by varying the incident angle of the cluster ions. The emission intensity of the intact ions was changed drastically due to the exposed dosage and incident angle of the cluster ions in contrast to the fragment ions. We discuss these results based on the manner in which the argon-cluster ions collide with the organic solid. 相似文献
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A phosphinite plays a role as a reversibly bound directing group for the regio- and diastereoselective hydroformylation of 2,5-cyclohexadienyl-1-carbinols. Of the two alkene functions only one was functionalized through hydroformylation to form a synthetically attractive quaternary carbon center leaving the second alkene function for potential further functionalization. 相似文献
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Kurono N Ohtsuga K Wakabayashi M Kondo T Ooka H Ohkuma T 《The Journal of organic chemistry》2011,76(24):10312-10318
Kinetic resolution of sterically hindered racemic α-tert-alkyl-α-hydroxy esters is performed by enantiomer-selective carbamoylation with the t-Bu-Box-Cu(II) catalyst (Box = bis(oxazoline)). The reaction with 0.5 equiv of n-C(3)H(7)NCO is carried out with a substrate-to-catalyst molar ratio of 500-5000 at -20 to 25 °C. The high enantiomer-discrimination ability of the catalyst achieves an excellent stereoselectivity factor (s = k(fast)/k(slow)) of 261 in the best case. A catalytic cycle for this reaction is proposed. 相似文献