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121.
122.
M Kodera Y Kawahara Y Hitomi T Nomura T Ogura Y Kobayashi 《Journal of the American Chemical Society》2012,134(32):13236-13239
The conversion of peroxodiiron(III) to high-spin S = 2 oxodiiron(IV) via reversible O-O bond scission in a diiron complex with a bis-tpa dinucleating ligand, 6-hpa, has been characterized by elemental analysis; kinetic measurements for alkene epoxidation; cold-spray ionization mass spectrometry; and electronic absorption, M?ssbauer, and resonance Raman spectroscopy to gain insight into the O(2) activation mechanism of soluble methane monooxygenases. This is the first synthetic example of a high-spin S = 2 oxodiiron(IV) species that oxidizes alkenes to epoxides efficiently. The bistability of the peroxodiiron(III) and high-spin S = 2 oxodiiron(IV) moieties is the key feature for the reversible O-O bond scission. 相似文献
123.
Aoi Kimishima Tomoyasu Hirose Akihiro Sugawara Takanori Matsumaru Kaoru Nakamura Ken Katsuyama Masaki Toda Hirokazu Takada Rokuro Masuma Satoshi Ōmura Toshiaki Sunazuka 《Tetrahedron letters》2012,53(23):2813-2816
Luminamicin (1) was found to exhibit selective antibacterial activity against anaerobic bacteria by our group in 1985. The concise structure of 14-membered lactone of 1 was synthesized. Construction of a versatile enol ether moiety was achieved by Stille cross coupling via hydrostanylation of the ethynyl ether, and a maleic anhydride moiety was derived from the furan constitution by the oxidation after the macrolactonization at a late-stage. 相似文献
124.
Jun Katsuyama Kazuki Matsumoto Ryo Sugiyama Shinya Hasegawa Mitsuru Shinagawa Yoshiki Yanagisawa 《Optical Review》2014,21(5):621-627
This paper describes the measurement of an organic photovoltaic using an electro-optic probe. We verify the validity of the electro-optic probe by comparing it with a conventional electric probe. The electric field distribution of the organic photovoltaic is examined on the basis of results of the test board measurement using the electro-optic probe and results of the test board simulation using an electromagnetic field simulator. We succeed in failure diagnosis of the organic photovoltaic in three failure modes. We found that the organic photovoltaic has a failure cell, and the electro-optic probe is successfully applied to failure diagnosis of organic photovoltaic. 相似文献
125.
We present a simple and inexpensive method for the capture and release of bacteria contained in an array of conical nanopores on a membrane inside a microfluidic device. As an example, we demonstrate that cyanobacteria can be captured, one bacterium per pore, in a defined orientation with over 500 bacteria per membrane with viabilities as high as 100%. The device can also specifically capture cyanobacteria from a mixed suspension of cyanobacteria and chlamydomonas with a selectivity as high as 90%. 相似文献
126.
Yano M Matsuhira K Tatsumi M Kashiwagi Y Nakamoto M Oyama M Ohkubo K Fukuzumi S Misaki H Tsukube H 《Chemical communications (Cambridge, England)》2012,48(34):4082-4084
A triarylamine-functionalized terpyridine ligand formed a highly coordinated complex with europium tris(β-diketonate), which displayed reversible 'ON-OFF' luminescence switching coupled with a ligand redox process of triarylamine/triarylaminium cations. 相似文献
127.
128.
Ohta Y Demura A Okamoto T Hitomi H Nagaoka M 《The journal of physical chemistry. B》2006,110(25):12640-12644
The methyllithium tetramer (CH3Li)4 structure in the bcc crystal has been theoretically optimized with the use of density functional theory calculations under the periodic boundary condition. The X-ray structure shows that the methyl-group conformation in tetramer in crystal takes the staggered form rather than the eclipsed form that is taken in the isolated tetramer, i.e., the crystal packing effect, and this has been reproduced for the first time. It is concluded that the staggered form is advantageous in crystal, as a whole, due to the larger electrostatic stabilization via the induced intratetramer multipolarization, although it should cause, simultaneously, smaller destabilization in intratetramer electronic energy. 相似文献
129.
[reaction: see text]. Reaction of propargyl acetate with water catalyzed by Hg(OTf)2 afforded vinyl ketone as the major product along with a dimeric vinyl mercuric product and normal hydration products in small amounts. The reaction is an alternative to the Meyer-Schuster and Rupe rearrangement applicable to primary alcohols, although the mechanism is entirely different. 相似文献
130.
Hitomi Terajima 《Annali di Matematica Pura ed Applicata》2007,186(1):99-144
In [as reported by Saito et al. (J. Algebraic Geom. 11:311–362, 2002)], generalized Okamoto–Painlevé pairs are introduced
as a generalization of Okamoto’s space of initial conditions of Painlevé equations (cf. [Okamoto (Jpn. J. Math. 5:1–79, 1979)])
and we established a way to derive differential equations from generalized rational Okamoto–Painlevé pairs through deformation
theory of nonsingular pairs. In this article, we apply the method to concrete families of generalized rational Okamoto–Painlevé
pairs with given affine coordinate systems and for all eight types of such Okamoto–Painlvé pairs we write down Painlevé equations
in the coordinate systems explicitly. Moreover, except for a few cases, Hamitonians associated to these Painlevé equations
are also given in all coordinate charts.
Mathematics Subject Classification (2000) 34M55, 32G05, 14J26 相似文献