A rapid method for monitoring the sodium thiocyanate content of aqueous solutions in the manufacture of polyacrylonitrile fibre

Conclusions A refractometric method for rapid analysis of sodium thiocyanate in technological PAN-fibre solutions has been developed. A procedure has been devised and recommended for introduction for performing measurements, which has been metrologically certified and has been tested in analytical control of PAN fibre.Saratov Nitron PO. Translated from Khimicheskie Volokna, No. 2, pp. 55–57, March–April, 1992.     

Self-similar solution of a hydraulic fracture problem for a poroelastic medium

A solution of a coupled problem on the propagation of a hydraulic fracture (HF) with respect to the processes of deformation and flow in a poroelastic medium is considered. The fracture is formed and developed under the impact of a Newtonian fluid pumped into it through a well. The sets of self-similar solutions are constructed. These solutions are used to describe the evolution of a penny-shaped shallow fracture in a poroelastic medium with a uniform pressure inside the fracture. This work is a part of the HF publication series, which are based on splitting the original equations into components in accordance with the incomplete coupling principle.     

Acoustic-Emission Procedure for Rejecting Defects in Multiple-Pass Girth Welds

Russian Journal of Nondestructive Testing - A procedure is proposed for rejecting girth welds based on an analysis of the main parameters of acoustic emission (AE) signals recorded during...     

The crystallization mode influence and magnetic field action upon the mechanical and thermal properties of composite materials on the basis of polymers and magnetic additives

The results of investigations of the temperature-time mode of the crystallization influence and magnetic field action upon the mechanic strength, magnetic permeability, and thermal properties of composites on the basis of polymers (PEHD, PVDF) and the magnetic additive BaO(Fe₂O₃)₆ have been presented. It has been shown that the changes of the mechanical strength, magnetic permeability, and the thermal properties of the magnetic composites being studied, with regard to the temperature-time mode of crystallization and processing in a strong constant magnetic field, can be interrelated with the change of the polymer matrix supermolecular structure, the degree of the phase interaction, and the interphase layer thickness.     

Electrothermopolarization influence upon the structure and properties of a composition on the basis of polyethylene and Co(AlO<Subscript>2</Subscript>)<Subscript>2</Subscript>

The influence of electrothermopolarization on the structure and properties (electret, strength) of a composition on the basis of polyethylene and a low-molecular dye Co(AlO₂)₂ was investigated. It was experimentally established that the additive Co(AlO₂)₂ changes the polyethylene structure. As a result, the electret properties of the composition change. Correlation of the strength properties with the changes of the degree of the crystallinity of the polyethylene was observed.     

Modeling of the Temperature Field on a Thermodiffusion‐Galvanizing Line

Results of mathematical modeling of the temperature field in the working volume of a thermodiffusiongalvanizing unit on the basis of the assumptions of convective heat exchange are given.