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Molecular dynamic simulation is used to simulate the corrosion process of Fe or Ni in liquid Cs by Large-scale Atomic/Molecular Massively Parallel Simulator. The embedded-atom method potential is used to describe the interaction of Fe–Fe, Ni–Ni, and Cs–Cs, and Morse two-body potential is used to describe the Fe–Cs and Ni–Cs atomic interaction. Temperature is considered as a critical condition in this work. Results indicate that corrosion is easy to occur in the systems. The increase in temperature can help the process of Cs corrosion. Compared to the Ni–Cs system, the Fe–Cs system has a higher atomic concentration function. The radial distribution function shows that Cs atoms are dissolved into the substrates, but the Fe and Ni substrates are still crystalline structures. Moreover, Cs in Fe or Ni is still a liquid phase. [ABSTRACT FROM AUTHOR]

• The accurate calculations of Cs adsorption on Mo(110) surface were performed by DFT, including surface structures, adsorption energy, and work function. • The calculation results indicated that the adsorption stability of Cs on the surface will be enhanced with oxygen co-adsorption. and the other hand, O may significantly reduce the surface work function in some cases. In this work, the O impurity particle adsorption on the Cs/Mo(110) surface, to determine the influence of O on Cs stability on Mo(110) surface and also the work function of Cs/O/Mo(110) surface, has been investigated by performing density functional theory (DFT). There are four independent adsorption sites on Cs/Mo(110) surface for O atom. No matter which adsorption site O was adsorbed, the surface adsorption energy of Cs increased. O atoms attract more charges due to the difference in electronegativity. Although this weakens the interaction between the Cs and Mo atoms, the O atom does connect them like a bridge, resulting in enhanced adsorption of Cs atom. In our model, the surface work function of Cs/Mo(110) is calculated as 1.835 eV. In some cases, the adsorption of O can dramatically reduce the surface work function to 1.633 eV. Conversely, O may also increase it, but this increase is not pronounced. This result suggests that the appropriate addition of O atoms may be beneficial to the development of high-efficiency negative ion sources. [ABSTRACT FROM AUTHOR]

• The work describes design of the cesium (Cs) oven for the prototype negative ion source of CFETR. • Thermal and mechanical simulations of the cesium oven are performed using finite element analysis. • Thermal stress analysis and analysis of material deformation caused by thermal expansion were also performed. • The cesium flux of the designed advanced cesium oven system is calculated. In order to support the design and manufacture the cesium (Cs) oven for the prototype negative ion source in the Chinese Fusion Engineering Test Reactor-Negative Ion Based Neutral Beam Injection (CFETR-NNBI) system, an advanced cesium oven is being set up at IFS. The design scheme is proposed based on the characteristics of the prototype negative ion source in the CFETR-NNBI system and combined with the international frontier research related to this aspect. Based on the reference to the Padova cesium oven, this article has designed a dedicated nozzle for the cesium oven and a transport channel more conducive to steam transport. A corrosion-resistant Cs reservoir and delivery tube is utilized. Precise control of cesium flux is achieved via remotely controlled switching valves and heating systems. The surface ionization detector is used to detect the cesium flux of the nozzle. And the thermal stability analysis, thermal transient analysis, thermal stress analysis and thermal deformation analysis were carried out on the design. The feasibility of the design is demonstrated through finite element analysis, which provides a theoretical basis for the next step of manufacturing. The cesium flux of oven is simulated and calculated, which provides reference for the subsequent device testing. [ABSTRACT FROM AUTHOR]