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101.
Masaru Matsuoka Akihiro Iwamoto Takeshi Ouchi Hiroshi Yoshioka Kazumi Nakatsu 《Journal of heterocyclic chemistry》1993,30(1):173-176
The structure of 1,4-dithiines obtained from orthodihalogeno heterocycles with thiocarbonyl compounds was determined by X-ray structure analysis of the intermolecular charge-transfer complex between 5,7,12,14-tetramethoxydibenzo[b,i]thianthrene and TCNQ. The formation of the thiazole ring has already been reported but the products were confirmed to be 1,4-dithiines by X-ray structure analysis and the previously reported results. 相似文献
102.
103.
A. Yoshioka K. Nomura M. Takeya K. Shimura K. Masumoto M. Yagi 《Journal of Radioanalytical and Nuclear Chemistry》1988,122(1):175-182
Determination of carbon in copper has been studied by photon activation analysis using 30 MeV bremsstrahlung. Chemical separation of carbon as CO2 was performed by the combustion method in a high flow rate of oxygen stream. It has been demonstrated that the trace amount of carbon in copper can be determined accurately and precisely, and that the detection limit is 0.02 g. 相似文献
104.
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108.
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
109.
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
110.
Tadakatsu Mandai Masashi Yamaguchi Yuka Nakayama Junzo Otera Mikio Kawada 《Tetrahedron letters》1985,26(22):2675-2676
Development of a new synthetic method for α-ketosilanes can be achieved by a sequence of alkylation of methoxy(phenylthio)trialkylsilylmethane and oxidation with NaIO4. 相似文献