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In the development of life support systems for long-term space missions, the most important tasks are the absorption of carbon dioxide from the air, the production of carbon dioxide with a concentration above 98 %, and the production of oxygen from carbon dioxide by the Bosch – Sabatier process. To solve these problems, a regenerative carbon dioxide absorber adapted to space flight conditions is required. The article proposes a new method for the production of chemosorbents based on hydrated zirconium oxide using polyacrylates as a binder and polymer matrix. The regenerated absorber of carbon dioxide for its application in space flights must meet the regulatory requirements of sanitary-chemical and toxicological safety of materials intended for the equipment of inhabited sealed rooms, be resistant to radiation and to the effects of mold. In the study of the processes of “sorption – desorption” of carbon dioxide, we have established the relationship between the technological parameters of the synthesis of chemosorbents and the kinetic parameters of the processes of mass-sorption of sorbate in the “sorption – regeneration” cycles. It is found that the optimal weight ratio of the “adsorbent – filler/polymer matrix” 89÷94/11÷6 is optimal in terms of the performance characteristics of the developed absorbers. It is shown experimentally that the main operational characteristics of the developed materials do not change under experimental conditions during 2000 “sorption – regeneration” cycles. The resulting chemosorbents are investigated by physicochemical analysis. Employing methods of gas chromatography and chromatomass spectrometry, we have conducted sanitary and chemical studies and toxicological assessment of the quantitative and qualitative composition of the components of gas release of the developed regenerated carbon dioxide absorber and air-gas mixture formed during the regeneration of the regenerated carbon dioxide absorber. Also we have carried out microbiological tests of samples of the regenerated absorber of carbon dioxide for resistance of material to influence of mold mushrooms. The results obtained confirm the possibility of using the developed materials in life support systems of manned spacecraft for deep space exploration.

Introduction. Morphological studies of animals (trachea, bronchi, lungs) exposed to the combined inhalation of chemicals in low concentrations showed the progression of structural changes, indicating the activation of inflammation and fibrosis in the lungs. The role of cytokine markers in developing inflammatory and fibrotic processes and remodeling lung tissue has been studied. Materials and methods. Male rats (180-200 g) were exposed to a mixture of chemicals (acetone, acetaldehyde, benzene) in low concentrations of 0.7-1.5; 0.9-1.4; 0.2-0.4 (mg/m3), respectively. The concentrations of IL-6, IL-10, IL-1b, IL-4, TGFβ1, TNFα cytokines (pg/ml) have been measured in the lung homogenate by enzyme-linked immunosorbent assay (ELISA). Microscopic anatomy of the lungs, tracheal wall, bronchi has been studied on the 30th day of exposure and the 15th and 90th days of the recovery period. Results. An increase in interleukin-4 and transforming growth factor TGFβ1 in the homogenate of the lung tissue was shown. An increase in lymphatic follicles, the number of lymphocytes, neutrophils, macrophages, and focal accumulations of eosinophils has been observed in the tracheal wall. In lymphoid infiltrates of the lung tissue - eosinophils, macrophages, and plasmocytes. Accumulation of eosinophilic exudate has been observed in some alveoli. The 90th day of the recovery period is characterized by a significant increase of TGFβ1 in the lung tissue, indicating fibrosis, as evidenced by the rise in the number of fibroblasts between the alveoli in the atelectasis zones of lungs. Conclusion. The chronic combined exposure to the mixture of chemicals in low concentrations is accompanied by a pro-inflammatory process in the lungs with the type II hypersensitivity and increasing IL-4 and TGFβ1 (a key mediator of profibrotic activity).

The article presents the results of a questionnaire survey of schoolchildren about learning problems during the new type of COVID 2019 coronavirus pandemic. The author analyzes issues related to the well-being of schoolchildren, their psychological state, relationships with people around them, and motivation to study. In conclusion, the author notes the need to organize distance learning, taking into account the physiological characteristics of children, compliance with the work and rest regime.