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1.
Reactions of perfluoropropylene and its oligomers with acetone oxime in the presence of a base afford perfluoroalkyl and/or perfluoroalkenyl ethers of acetone oxime. When heated to 100 °C, the 3-perfluoro-2-methyl-2-pentenyl ether of acetone oxime (3) is quantitatively converted to 4-hydroxy-3-methyl-5,5-bistrifluoromethyl-4-pentafluoroethyl-1-pyrroline (4), the structure of which was established by X-ray diffraction analysis. A convenient one-stage synthesis of perfluoro-3-isopropyl-4-methyl-3-penten-2-one (7) was proposed.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1068–1072, June, 1994.  相似文献   
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Dehydrofluorination ofO-(-hydroperfluoroisobutyl)acetone oxime affords 2,2-bis(tri-fluoromethyl)-5-methyl-4-pyrrolin-3-one; the molecular structure of the latter was unambiguously established by X-ray diffraction method.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 951–953, May, 1994.  相似文献   
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Technical Physics - Scanning electron microscopy and X-ray diffractometry are used to study surface morphology and crystal structure of iron borate FeBO3 annealed at different temperatures....  相似文献   
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The resonance microwave absorption at wavelengths 871, 406, 305, and 118 μm in tetragonal layered perovskites HoBa2Cu3O x (x = 6.0, 6.3) in pulsed magnetic fields up to 40 T has been detected. This absorption is caused by the electronic transitions between low lying levels of the Ho3+ ion in the crystal field. The positions and intensities of the basic resonance absorption lines for the crystal with x = 6.0 in the magnetic field oriented along the tetragonal axes are adequately described in terms of the tetragonal crystal field with known interaction parameters. To explain the weaker absorption lines, it is necessary to take into account the effect of the inhomogeneous orthorhombic and monoclinic components of the crystal field, which are due to disorder in the oxygen subsystem. This effect is more pronounced in the absorption spectra of the crystal with x = 6.3 for which the oxygen disorder is more pronounced.  相似文献   
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Journal of Experimental and Theoretical Physics - The structural (lattice metric) and elastic characteristics of ErBaCo4O7 + x cobaltites, which are subjected to different heat treatment and are...  相似文献   
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The transition caused by a change in the ground state of a rare-earth ion upon level crossing, an analogue of the induced Jahn-Teller transition in rare-earth compounds, is observed. It is shown that a jumpwise change in the Jahn-Teller interactions of α and γ symmetries, caused by a change in the corresponding quadrupole moments in DyPO4 upon level crossing, diminishes the critical field by ~20 kOe and leads to a sharper change in magnetization M and differential magnetic susceptibility dM/dH near the crossover point.  相似文献   
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