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Based on the results of CNDO and INDO quantum-chemical calculations, the possibility of a vinyl substitution (along with an addition) upon reaction of perfluoropropylene, perfluoroisobutylene, and trifluorochloroethylene with alcohols, thiols, and amines, and the absence of a similar reaction in the case of tetrafluoroethylene is explained. The calculations allow the prediction that a vinyl substitution should take place in similar reactions of 1,1-di- and trifluoroethylenes, but not with mono- and 1,2-difluoroethylenes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2802–2805, December, 1991. 相似文献
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Bekzat ABDIKADYR Alp KILI Onur ALEV Serkan BÜYÜKK
SE Zafer Ziya
ZTÜRK 《Turkish Journal of Chemistry》2021,45(2):295
Pristine and WO3 decorated TiO2 nanorods (NRs) were synthesised to investigate n-n-type heterojunction gas sensing properties. TiO2 NRs were fabricated via hydrothermal method on fluorine-doped tin oxide coated glass (FTO) substrates. Then, tungsten was sputtered on the TiO2 NRs and thermally oxidised to obtain WO3 nanoparticles. The heterostructure was characterised by X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy. Fabricated sensor devices were exposed to VOCs such as toluene, xylene, acetone and ethanol, and humidity at different operation temperatures. Experimental results demonstrated that the heterostructure has better sensor response toward ethanol at 200 °C. Enhanced sensing properties are attributed to the heterojunction formation by decorating TiO2 NRs with WO3. 相似文献
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Zeph A. Landau 《Geometriae Dedicata》2002,95(1):183-214
An inclusion of II
1 factors NM of finite index has as an invariant, a double sequence of finite-dimensional algebras known as the standard invariant. Planar algebras were introduced by V. Jones as a geometric tool for computing standard invariants of existing subfactors as well as generating standard invariants for new subfactors. In this paper we define a class of planar algebras, termed exchange relation planar algebras, that provides a general framework for understanding several classes of known subfactor inclusions: the Fuss–Catalan algebras (i.e. those coming from the presence of intermediate subfactors) and all depth 2 subfactors. In addition, we present a new class of planar algebras (and thus a new class of subfactors) coming from automorphism subgroups of finite groups. 相似文献
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B. V. Landau 《Foundations of Physics》1973,3(4):499-500
An error in Gruber's paper, Quantization in Generalised Coordinates, and the reason for this kind of error are pointed out. A partial answer to the problem posed by the paper is stated. 相似文献