Selektivitätsuntersuchungen an einer zweischichtenfraktionierung von polyäthylenterephthalat

The concentration dependence of the selectivity in fractionation experiments with polyethylene terephthalate has been investigated. The values obtained with 0.25% solutions showed close approximation to the SCHULZ-FLORY distribution. Lowering the concentration resulted in an essential increase of efficiency. Almost quantitative fractionation was achieved with various model blends of polyethylene terephthalate samples having different molecular weight.     

Study of the hemicelluloses which are dissolved in the alkali after mercerization and press-out of deciduous and of coniferous celluloses

Conclusions The monosaccharide compositions of the polysaccharide fractions of hemicelluloses isolated from press alkalis from viscose manufacturing, where this alkali has been used to process cellulose from coniferous or deciduous wood, have been compared.It has been found that the content of xylan, isolated in the form of a water-insoluble fraction, is considerably higher in deciduous cellulose than in coniferous cellulose.On cyclic use of the alkali in manufacturing, the water-soluble fraction of the polysaccharides accumulates xylose, probably as a result of partial depolymerization of xylan.In the alkali solutions, the content of organic substances of a nonsugar nature gradually increases; this is apparently connected with decomposition of the polysaccharides under conditions of prolonged alkaline treatment.Translated from Khimicheskie Volokna, No. 1, pp. 28–29, January–February, 1986.     

Application of vibrostabilization to turbodrill components

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 4, pp. 13–14, April, 1989.