"Radiochemistry" is the study of chemical transformations of radioactive substances, dealing with radioactive waste from nuclear power engineering, solving radioecology problems, developing methods for manufacturing sources of radioactive emissions, and isotope separation. "Radiation chemistry" is the study of chemical changes caused by ionizing radiation, as well as the research of radiation-chemical processes, the creation of methods for predicting the radiation resistance of various materials, and the development of ways for protecting them from destruction. Radiation chemistry is also responsible for the development of radiation-chemical methods for the synthesis of organic compounds and the production of modified materials for medicine, biotechnology, and membrane technology; the development of new radiation-resistant materials, the radiation modification of polymers; and the development of new radiation-resistant materials.