Mechanisms of the Action of Fire-Retardants on Reducing the Flammability of Certain Classes of Polymers and Glass-Reinforced Plastics Based on the Study of Their Combustion.

In the present review, using an integrated approach based on the experimental and theoretical study of the processes of thermal decomposition and combustion of practically important polymers, such as polymethyl methacrylate, polyethylene, and glass-fiber-reinforced epoxy resin, the features of the mechanism for reducing the combustibility of these materials with phosphorus-containing flame-retardants (FR), as well as graphene, are identified. A set of original experimental methods was developed and applied that make it possible to study the kinetics of thermal decomposition and the thermal and chemical structure of the flames of the studied materials, including those with FR additives, as well as to measure the flame propagation velocity, the mass burning rate, and the heat fluxes from the flame on the surface of a material. Numerical models were developed and tested to describe the key parameters of the flames of the studied polymeric materials.

Fully Coupled Three-Dimensional Simulation of Downward Flame Spread over Combustible Material.

Three-dimensional simulations of laminar flame propagating downwards the vertical surface of a rigid polyurethane slab heated by a radiative panel are presented and compared with the measurement data. The gas-phase model (ANSYS Fluent) allows for finite-rate volatile oxidation, soot formation and oxidation, emission, transfer, and absorption of thermal radiation. The solid-phase model Pyropolis considers heat transfer across the material layer and generation of combustible volatiles in thermal decomposition of the material.

[The surgical treatment of scoliosis with the use of the Rodnianskiĭ-Gupalov endocorrector at a pediatric orthopedic sanatorium].

102 patients with scoliosis at stages II, III and IV aged from 7 to 18 years have been operated making use of Rodnianski'i-Gupalov endocorrector. Half of the patients had scoliosis at stage IV. The best results have been observed in the patients aged from 7 to 12 years at stage 11 and beginning of stage III of scoliosis (to 35 degrees).