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1.
MM. J. Duflos D. Letouz G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1083-1084
This communication describes the synthesis of l-methyl-2,3-diformylpyrrole. This new compound is used to prepare a new heterocycle, l-methylcyclohepta[b]pyrrol-6-one and thus allows a new synthesis of l-methylpyrrolo[2,3-d]pyridazine. 相似文献
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The title compound was obtained using the Sandmeyer reaction starting from 2-aminophenoxathiine. A new synthesis of N-methylpyrrolo[2,3-b]phenoxathiin-2,3-dione was also presented. Chemical and spectral data supporting the structure of the newly synthesized compounds were given. The isatin analogue, 1-methylpyrrolo-[2,3-b]phenoxathiin-2,3-dione-10, 10-dioxide, could not be obtained.Faculty of Chemistry, Organic Chemistry Department, University of Bucharest, 90–92 Panduri Road, Romania. Faculty of Pharmacy, Organic Chemistry Department, University of Medicine and Pharmacy Carol Davila, Bucharest, Romania. Published in Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 396–399, March, 1998. 相似文献
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M. M. Maior V. T. Vrabel I. P. Prits N. F. Korda M. I. Gurzan Yu. M. Vysochanskii 《Physics of the Solid State》2005,47(9):1734-1739
The dielectric properties of layered crystals of CuInP2(SexS1?x)6 solid solutions are studied at x = 0.02, 0.05, 0.20, and 0.40. At a low selenium content (x ≤ 0.05), the solid solutions undergo a transition to the phase with short-range polar order. This transition manifests itself as a diffuse maximum in the temperature dependence of the permittivity ε′(T). Ferroelectric ordering in the solid solutions under investigation is suppressed at x > 1. It is assumed that the structural disordering initiated by the substitution of atoms in the anion sublattice of the solid solutions at 0.1 < x < 0.75 leads to the formation of the state of structured glass. The dielectric relaxation dispersion observed in the radio-frequency range at temperatures of 80–140 K is associated with the freezing of the relaxation dynamics of individual copper atoms. 相似文献
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A. V. Skazochkin Yu. K. Krutogolov V. I. Maior Yu. I. Kunakin A. A. Matyash G. G. Bondarenko 《Technical Physics》1997,42(9):1031-1034
The influence of oxygen introduced in the gaseous phase on the formation of defects in GaP epitaxial layers is investigated
by deep-level transient spectroscopy. The extremal dependences of the concentrations of charge carriers and electron traps
with energy E
c−0.24 eV on the oxygen flux are discussed.
Zh. Tekh. Fiz. 67, 52–55 (September 1997) 相似文献
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MM. P. Duballet A. Godard G. Queguiner P. Pastour 《Journal of heterocyclic chemistry》1973,10(6):1079-1080
This article describes the synthesis of a new heterocycle, pyrido[2,3,f]phtalazine and three new diformylquinolincs. 相似文献