Properties of High-Strength Aramid Fiber Textile Materials for Protective Clothing

Fibre Chemistry - An analysis of the aramid fiber market including the range of industrial textile materials containing chemical fibers for specialized protective clothing of metallurgical workers,...     

Assessment of the biodegradation intensity of organic compounds in water using the squalene biomarker

An approach based on the quantitative determination of squalene biomarker by the chromato-mass-spectrometry method has been proposed for assessment of the intensity of biotransformation of organic compounds in water. The method sensitivity amounted to 5 × 10^–5 mg/dm³. It is recommended to use squalene for the detection of stagnant zones in the city water distribution system and the biological activity in filtering layers of wells of infiltration water intakes and in filters for industrial and domestic water treatment. An enhanced intensity of biotransformation processes is related to the rise of squalene concentration in the tested water.     

Effect of High-Frequency Capacitive Discharge Plasma on the Structure and Properties of Flax and Lavsan Materials

Analysis of the diffraction pictures of flax and polyester fibres suggests that the differences in untreated and plasma-treated samples primarily consists of their degree of crystallinity. Treatment of flax and lavsan fibres causes coalescence of regions of coherent scattering and partial elimination of the defects defining the boundaries of these regions so that the diffraction maxima become narrower. The decrease in the defectiveness of the fibres is accompanied by an increase in their crystallinity. The capillarity is increased by 2.5–.5 times, primarily in flax fabrics, in treatment with HFC discharge plasma for 180 sec due to evacuation of the pore volume, removal of some of the wax-forming substances and sizing, and splitting of the fibres and a change in the free energy of the pore surface and capillaries. It was found that treatment with low-temperature plasma increases the strength of natural and synthetic fibres by 55–64%. __________ Translated from Khimicheskie Volokna, No. 4, pp. 47–50, July–August, 2005.