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The effect of γ-radiation on the average molecular weight and the molecular-weight distribution of chitosan has been studied. The analysis of samples by gel permeation chromatography/size exclusion chromatography (GPC/SEC) has shown that the amount of high-molecular-weight fractions decreases and the amount of fractions containing low-molecular-weight chitosans (

The γ-radiolysis of solid chitosan was studied. The radiolysis products hydrogen and ammonia were determined by chromatography and spectrophotometry (with Nessler’s reagent), respectively, and the amino groups were determined by potentiometic titration. The radiation-chemical yields were found to be GH2 = 2.0 ± 0.3; GNH3 = 5.8 ± 0.4 and G−NH2 = 2.9 ± 0.8. The molecular mass of chitosan decreases with an increase in the absorbed radiation dose because of its degradation (GD = 3.6 ± 0.4). A long-term posteffect was observed after irradiation. This is a preliminary report on the study concerning the search for optimal conditions of the synthesis of membranes from modified chitosan for removal of cadmium ions.

Radiolysis of alkylnaphthalene oils was studied. It was shown that the radiation-chemical yield of hydrogen grows linearly (from 0.26 for KR-007A oil to 0.78 for KR-019 oil) with an increase in the average (with allowance for the composition) length of the alkyl chains. A number of liquid alkanes and alkenes (C5–C12) along with naphthalene were identified in the radiolysis products. Dimers and polymers make 2–10% depending on the radiation dose. Alkylnaphthalene oils used as additives for synthetic oils of the WM-5 type substantially improve the radiation resistance of these oils.

The effects of 60Co γ-radiation on D-glucose, L-glucose, D-galactose, L-galactose, D-mannose, and L-mannose were studied. The yields of gaseous radiolysis products were determined. The curves of radical buildup and decay in crystalline samples were obtained. Conclusions on the relative radiation stability of these D- and L-monosaccharides to the action of nonpolarized radiation were drawn.

Radiolysis of a number of synthetic oils based on polyalphaolefins (WM-5, PAO-2, PAO-4, PAO-6, and PAO-8) has been studied. The radiation-chemical yields of hydrogen, low-and high-molecular-weight products (up to C100) are reported. So, for PAO-4 oil (composition of the oil: 80 % of C30, 13 % of C40, 3 % of C50) the yields of products of radiolysis (1/100 eV) make: \( G_{H_2 } \) = 3.7, G C60 = 0.5.

Radiolysis of chloroalkanes (from chloropropanes to chlorodecane) has been investigated. Hydrogen and hydrogen chloride are the main products of decomposition. Their concentrations linearly grow with the dose in the examined interval up to 150 kGy. The radiation-chemical yield of hydrogen increases from 0.72 for 1-chloropropane to 1.3 for 1-chlorodecane. The opposite trend is observed in the case of HC1: 3.7 for 1-chloropropane and 1.7 for 1-chlorodecane. Products of dechlorination, chlorination (di-and trichloroalkanes) with G 0.8–4.0, isomerization with G up to 90, as well as oligomerization products, have been identified in the liquid products.

The γ-radiolysis of the α-and β-anomers of D-glucose was studied. The kinetic parameters of mutarotation of irradiated glucoses were determined by polarimetry. The reaction rate constants are independent of the radiation history of samples. The yields of hydrogen from irradiated glucoses were determined by chromatography. The radiation stability of the powdered anomers was the same.

The radiolysis of vacuum oils was studied. The radiation-chemical yields of hydrogen varied over the range 1.6–3.2 depending on oil brand. A number of liquid radiolysis products were identified. It was found that, in the presence of oxygen, ketones were the main products of the radiation-induced oxidation of oils.