Liquid-phase epitaxy of Potassium Niobate

The possibility of potassium niobate films growing by means of liquid phase epitaxy technique was investigated. The physical and chemical analyses of K₂O-V₂O₅-Nb₂O₅ system were carried out. Corundum wafers with {1¯210} and {0001} orientations served as substrates. The grown films were 10–30 μm thick. The grown heterostructures had a sharp, phase boundary line substrate-film. Epitaxial layer perfection was investigated by X-ray and electronographic methods.     

Synthesis of 2-Aminocarboxylic Acids on the Basis of Metalated Lithium Acylates

2-Aminocarboxylic acids have been synthesized through the reaction of lithium acylate α-carbanions with alkyl nitrites to form α-hydroxyiminoacylates, followed by reduction of the latter with tin chloride. The reactions of lithium acylate α-carbanions, generated by the metalation of carboxylic acids with lithium diisopropylamide at 35–40°С in THF under argon, with alkyl nitrites at 45–50°С give 2-hydroxyiminocarboxylic acids in 55–97% yields. The reduction of 2-hydroxyiminocarboxylic acids with tin(II) chloride in conc. HCl at 20–25°С leads to 2-aminocarboxylic acid hydrochlorides in 52–94% yields.     

Correlation in statistical theory of liquid crystals

A statistical theory which takes into account correlation between orientations of rod-like molecules in a liquid crystal is proposed. This theory is a variant of thermodynamical perturbation theory. The proposed representation of the distribution function in spherical functions enables us to introduce consistently long-range order parameters as well as to analyze the thermodynamics of a liquid crystalline phase described by a rotation-invariant Hamiltonian.     

Mass-spectrometric investigation of some 2,6-dimethyloxazolo[4,5-d]pyrimidine derivatives

The fragmentation of the molecular ions of 4-chloro- and 4-alkylamino -2,6-dimethyloxazolo[4,5-d]pyrimidines involves splitting out or fragmentation of the substituent in the 4 position or cleavage of the oxazole ring. The compositions of the fragment ions were determined on the basis of the high-resolution mass spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1255–1258, September, 1982.