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  • Author or Editor: I. Andreeva x
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Abstract  

Flow birefringence (FB) has been investigated in solutions of products of hydrolytic degradation of poly(naphthoyleneimide benzimidazole) (PNIB) in 96% sulphuric acid PNIB solutions have previously been subjected to heating at various temperatures from 65 to 120°C and then investigated at 22°C by FB and viscometry. A monotonic decrease in intrinsic viscosity and the molecular weightM of thermal degradation products with increasing degradation temperature was detected. At the same time, the shear optical coefficients in series of products with decreasingM first increases and then, at treatment temperatures exceeding 90°C, decreases with decreasing [ν] in accordance with decreasingM of the product. Possible reasons for the detected anomaly have been discussed.

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Abstract  

The extraction of Y(III) using molten C7−C9 monocarboxylic acids and stearic acid with paraffin was studied. The optimal conditions for the extraction as well as the effect of different factors on the process were established. The method can be used for the concentration of Y(III) from dilute solutions with subsequent X-ray fluorescence determination in the solid extractants.

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Influence of soybean mosaic virus (SMV) on activity of 1,3-b-D-glu­nase, a-D-mannosidase, b-D-galactosidase and b-D-glucosidase in leaves of extremely resistant (cv. Devamusume) and sensitive (cv. Primorskaya 529) young soybean plants was studied. Enzymes can be put in order of increase of their activities as follows: b-D-glucosidase, b-D-galactosidase, a-D-mannosidase and 1,3-b-D-glucanase independently of a cultivar. High level of 1,3-b-D-glucanase activity was detected in leaves of the healthy resistant plants in comparison to the healthy sensitive plants. In response to systemic invasion with SMV, the activity of 1,3-b-D-glu­canase in leaves of resistant cultivar did not change. Infection of the sensitive cultivar with SMV caused a considerable increase in activity of 1,3-b-D-glucanase in the leaves above the inoculated leaves. After infection with SMV no difference had been found in the level of activity of glycosidase between the soybean cultivars, though the virus caused mosaic symptoms and deformation and roll of leaves of the sensitive cultivar.

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