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101.
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103.
Omori Hideki Maeda Yoshiaki Miyazaki Naoya Yoshioka Akira 《Letters in Mathematical Physics》1998,46(2):171-180
It is well known that the Moyal bracket gives a unique deformation quantization of the canonical phase space R2n up to equivalence. In his presentation of an interesting deformation quantization of the Poisson algebra of Laurent polynomials, Ovsienko discusses the equivalences of deformation quantizations of these algebras. We show that under suitable conditions, deformation quantizations of this algebra are equivalent. Though Ovsienko showed that there exists a deformation quantization of the Poisson algebra of Laurent polynomials which is not equivalent to the Moyal product, this is not correct. We show this equivalence by two methods: a direct construction of the intertwiner via the star exponential and a more standard approach using Hochschild 2-cocycles. 相似文献
104.
F. Higashide K. Omata Y. Nozawa H. Yoshioka 《Journal of polymer science. Part A, Polymer chemistry》1977,15(8):2019-2028
Permeability to oxygen of poly(methyl methacrylate) (PMMA) films containing glass flakes (GF) was investigated. The glass flakes were treated with five kinds of silanes and K2Cr2O7-H2SO4 solution to improve the affinity with PMMA. The permeability curves were classified into five representative types, which depend on the pretreatment of the glass flakes and the type of silane used as a coupling agent. The factors which influence permeability were studied from the point of view of permeative retardation with the aid of several methods, such as determination of the apparent density of the glass flakes treated with the silanes, the shearing and tensile strength of the PMMA films containing the glass flakes, ESR spectra of films irradiated by γ-rays, and x-ray diffraction patterns of the films. It was found that the three very effective methods to retard the permeability are (a) pretreatment of the glass flakes with NaOH, (b) treatment with γ-methacryloxypropyltrimethoxysilane or ditrimethylsiloxymethylsilane, and (c) heat pressing of the films. The lowest permeability constant which was attained in this study was about one-eighth that with PMMA alone. 相似文献
105.
Shinichi Ueji Kazumi Nakatsu Hiroshi Yoshioka Kenji Kinoshita 《Tetrahedron letters》1982,23(11):1173-1176
The crystals of the title compound contain both intra- and inter-molecular OH?π hydrogen bonds (the first example of bifurcated OH?π bonds), the stereochemistry of which has been elucidated by an X-ray structure analysis; this bifurcated bond is also supported by the observation based on the IR spectrum of the crystals. 相似文献
106.
Teruji Tsuji Takahiro Kataoka Mitsuru Yoshioka Yuji Sendo Yasuhiro Nishitani Shoichi Hirai Takashi Maeda Wataru Nagata 《Tetrahedron letters》1979,20(30):2793-2796
The benzyl ester protecting group in β-lactam derivatives can be cleanly removed by treatment with aluminum trichloride under mild conditions, preferably in the presence of anisole, to give the corresponding free acids in high yields. 相似文献
107.
108.
Yuji Oikawa Tatsuyoshi Tanaka Kiyoshi Horita Tadao Yoshioka Osamu Yonemitsu 《Tetrahedron letters》1984,25(47):5393-5396
The DMPM (3,4-dimethoxybenzyl) protection for hydroxy function was deprotected more readily than the MPM (p-methoxybenzyl) protection by DDQ oxidation under neutral conditions, and applied to the synthesis of some synthons to macrolide and polyether antibiotics. 相似文献
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110.