Anomalous mass transport in the vicinity of the interface of two metallic media

Diffusion of nickel in copper was studied experimentally in a temperature range of 250–375°C in the “coating (nickel)-metal (copper)” system using a radioactive isotope ⁶³Ni. Anomalously high values of the diffusion coefficients and an anomalously low value of the activation energy were found. To explain the effect, a new way of describing the diffusion phenomena in the vicinity of the interface of two metallic media is suggested, which takes into account the presence of high gradients of chemical potentials near the boundary. Based on the principles of nonlinear thermodynamics of irreversible processes, a system of differential equations of diffusion in the vicinity of the interface was obtained. Analysis of the kinetics of the diffusion zone formation revealed that chemical-potential gradients significantly accelerate the diffusion process in the vicinity of the interface. A comparison of the calculated kinetics of the formation of a diffusion zone with that obtained upon the experimental investigation of diffusion shows their qualitative agreement.     

(Allylamino)silanes: Synthesis,Properties, and Prospects of Use in Producing New Materials

Russian Journal of General Chemistry - Methods for the synthesis and purification of dimethyldi(allylamino)silane, ethyldi(allylamino)silane, and methyltri(allylamino)silane were developed. The...     

Tricyclo[7.3.1.02,7]tridecanes with an Amino Group at the Bridging Carbon. Synthesis and Stereochemistry

Hydroamination of tricyclo[7.3.1.02,7]tridec-2(7)-en-13-one according to Leukart reaction furnished (tricyclo[7.3.1.02,7]tridec-2(7)-en-13-yl)methanamides stereoisomeric at C¹³ atom. The corresponding epoxides were prepared therefrom. The unsaturated and epoxidized methanamides were hydrolyzed into amines that were converted into Schiff bases.The configurations of substances were established.     

Gasdynamic analysis of a pneumatic line launcher

A solution to the problem of motion of a projectile in the bore of a pneumatic line launcher equipped with a fast-acting valve of large clear opening is obtained. The results are represented in the user-friendly graphical form and include a variety of the gasdynamic and design parameters of the launcher that influence the projectile velocity. The calculated data are in good agreement with data of multiparametric experiments.     

Viscosity additives to lubricating oils,based on alkyl methacrylates and allyl monomers

New viscosity additives to oils, based on copolymers of alkyl methacrylates and allyl monomers, were developed.