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Finely dispersed powders of gadolinium hydroxide are obtained by chemical deposition (dispersing). The influence of various factors on the powder characteristics such as dispersity, morphology, and chemical composition is investigated. The dependence that the mentioned characteristics have on the character of the anion of the gadolinium salt, the concentration and acidity of its solution, and the concentration of the precipitant and pH of precipitation, is established. The optimal results are observed with the use of diluted chloride solutions of gadolinium and a 5–10 wt % precipitant in the form of the NH3 solution.

With the use of the methods of dynamic mechanical analysis and thermomechanical analysis, the structural transformations of polyacrylonitrile fibers during heating are studied. It is shown that, regardless of the degree of macromolecule orientation, the fibers not exposed to heating are characterized by an amorphous ordered structure with an ordered mesophase. During heating, the fiber acquires a single-phase structure owing to transition of the amorphous component to the mesophase.

A decrease in the persistence characteristics of staphylococci under the influence of microclimate in a spelean pit has been demonstrated under experimental conditions. Clinical investigations have confirmed the capacity of speleotherapy to decrease the microbial contamination of the upper respiratory tract and to inhibit the persistence properties of staphylococcal microflora in children with respiratory allergosis, which seems to be the basis of the positive effect achieved by treatment with microclimate in a spelean pit.