Vaporization and thermodynamics of the Cs O-MoO system studied using high-temperature mass spectrometry.

Rationale: Cesium and molybdenum are fission products of uranium dioxide fuel in nuclear reactors, which interact with each other depending on the oxygen potential of the fuel. This leads to formation of various compounds of the Cs O-MoO system, which are exposed to high temperatures during operation of a reactor or a severe accident at a nuclear power plant. This is why the study of the vaporization and thermodynamics of compounds in the Cs O-MoO system is important.

High-temperature mass spectrometric study of vaporization and thermodynamics of the Cs O-B O system: Review and experimental investigation.

Rationale: The compounds in the Cs O-B O system are of particular interest for nuclear applications since cesium borates may be formed during accidents in nuclear reactors, affecting the rate of release of radiotoxic isotopes into the environment. Thus, information on the vaporization and thermodynamic properties of cesium borates is necessary for simulation and modeling of the isotope release processes taking place during the nuclear reactor accidents.

Methods: Compounds in the Cs O-B O system were synthesized by the co-crystallization method with subsequent sintering.

High-temperature mass spectrometric study of thermodynamic properties in the UO -ZrO system.

Rationale: The UO -ZrO solid solution at high temperatures is the key system of modern nuclear science and technology in the context of the safety operation of nuclear cycles, the consequences of severe accidents, and the incorporation of nuclear waste. Urgent needs of the continuation of experimental studies of this system at temperatures up to 3000 K are aimed at preventing severe accidents similar to Chernobyl and Fukushima when the thermodynamic approach is used for the prediction of high-temperature behavior of materials.

Methods: This investigation was carried out using the Knudsen effusion mass spectrometric method using the MS-1301 magnetic sector mass spectrometer.