Orientational glasses with CO molecules occupying 26 and 90 % of the octahedral interstitial sites in the <$E roman C sub 60> lattice have been investigated by the dilatometric method in a temperature interval of 2,5 - 22 K. At temperatures 4 - 6 K the glasses undergo a first-order phase transition which is evident from the hysteresis of the thermal expansion and the maxima in the temperature dependences of the linear thermal expansion coefficients <$E alpha ( T )>, and the thermalization times <$E tau sub 1 ( T )> of the samples. The effect of the noncentral <$E roman {CO~-~C} sub 60> interaction upon the thermal expansion and the phase transition in these glasses was clarified by comparing the behavior of the properties of the <$E roman {CO~-~C} sub 60> and <$E roman {N sub 2~-~C} sub 60> solutions.The sorption of <^>4He by graphene oxide powders thermally reduced at T = 200, 300, 500, 700, 900 <^>oC has been investigated in the interval 1,5 - 290 K. The measured dependence of the quantity of sorbed helium upon the reduction temperature shows up as a nonmonotonic curve. The highest quantities of helium were sorbed by the samples reduced at T = 300 and 900 <^>oC. It is assumed that the thermal reduction of graphite oxide by heating it to 300 <^>oC causes evaporation of the water intercalated in the spacings of the carbon layers, this results in exfoliation of the graphene planes, which enhances the sorptive capacity. Heating the samples to 900 <^>oC generates numerous defects in the carbon planes, as a result, the interlayer spacings become accessible for sorption, which enhances the sorptive capacity.The kinetics of the sorption and the subsequent desorption of <^>4He by the starting graphite oxide (GtO) and the thermally reduced graphene oxide samples (TRGO, Treduction = 200, 300, 500, 700 and 900 <^>oC) have been investigated in the temperature interval 1,5 - 20 K. The effect of the annealing temperature on the structural characteristics of the samples was examined by the x-ray diffraction (XRD) technique. On lowering the temperature from 20 to 11 - 12 K, the time of <^>4He sorption increased for all the samples, which is typically observed under the condition of thermally activated diffusion. Below 5 K the characteristic times of <^>4He sorption by the GtO and TRGO-200 samples were only weakly dependent on temperature, suggesting the dominance of the tunnel mechanism. In the same region (T << 5 K) the characteristic times of the TRGOs reduced at higher temperatures (300, 500, 700 and 900 <^>oC) were growing with lowering temperature, presumably due to the defects generated in the carbon planes on removing the oxygen functional groups (oFGs). The estimates of the activation energy (Ea) of <^>4He diffusion show that in the TRGO-200 sample the Ea value is 2,9 times lower as compared to the parent GtO, which is accounted for by GtO exfoliation due to evaporation of the water intercalated in the interlayer space of carbon. The nonmonotonic dependences Ea(T) for the GtO samples treated above 200 <^>oC are determined by a competition between two processes - the recovery of the graphite carbon structure, which increases the activation energy, and the generation of defects, which decreases the activation energy by opening additional surface areas and ways for sorption. The dependence of the activation energy on Treduction correlates well with the contents of the crystalline phase in GtO varying with a rise of the annealing temperature.

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