In order to enhance the efficiency of the interpretation of surface images obtained with a side scanning sonar, it is proposed to supplement the standard processing software with a program for ...obtaining acoustic stereo images. Examples of such images synthesized with this program using the data of a bottom sonar survey with a side scanning sonar and an echo sounder are presented. The cases are considered when the information on the bottom relief contained in sonar images obtained with a standard side scanning sonar or its modifications can be used instead of the data of an echo sounding survey.
Zinc enolates obtained from methyl 4-bromo-2,2-dimethyl-3-oxo-4-phenylbutanoates and zinc react with aromatic aldehydes to form 6-aryl-3,3-dimethyl-5-phenyl-2,3,5,6-tetrahydropyran-2,4-diones as a ...single geometric isomer.
In an acidic nitrate solution containing no less than 10^sup -4^ mol/l Ag^sup +^, potentiostatic anodic dissolution of silver from its alloy with gold (up to 35 at. %) already in about 10 s is ...limited by the solid-phase mutual diffusion of the components. A number of diffusion-kinetic dissolution models taking into account contributions from the liquid-phase mass transfer, segregation in the surface layer, microroughness of the surface, shift of the alloy-solution interface, as well as the relaxation of nonequilibrium vacancies into a transient dissolution current are considered. The diffusivities and mutual diffusivities of the components, concentrations of nonequilibrium vacancies, and thickness of the diffusion zone estimated in terms of these models are compared. The effect of the overpotential and alloy composition is discussed. The main source of nonequilibrium monovacancies in the amount 14 orders as high as the equilibrium one is found to be the dissolution of silver. The efficiency of the sinks, among which the formation of bivacancies seemingly dominates, is not high, which predetermines the slowness of relaxation processes in the solid-phase diffusion zone.PUBLICATION ABSTRACT
Ethyl 2,4-dibromo-2,4-dimethyl-3-oxopentanoate reacts with zinc and aliphatic or aromatic aldehydes to furnish 3,5,5-trimethyl-6-R-2,3,5,6-tetrahydropyran-2,4-diones as a single geometrical isomer ...that in polar solvents converts into enol form.
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