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Hong-Bo Zhou

Publications and source records attributed to Hong-Bo Zhou.

3 recordsLinked to original sources

Stress-driven dynamic evolution of core-shell structured cavities with H and He in BCC-Fe under fusion conditions

Understanding the dynamic behavior of microstructures formed under fusion conditions is critical for designing high-performance structural materials for fusion reactors. Under fusion conditions, cavities of core-shell structures are formed due to the interaction between irradiation-induced vacancies and H and He atoms produced via transmutation. In this study, thermodynamic analysis and molecular dynamics simulations are combined to investigate the atomic-scale mechanisms and dynamic response of core-shell cavities formed in BCC-Fe under applied stress/strain fields. The thermodynamic analysis provides both the foundational reference for cavity structures under fusion neutron irradiation and the initial configurations for atomistic simulations. Building on this framework, atomic-scale simulations demonstrate that H and He play a decisive role in the stress-strain response and the evolution of elastic-plastic deformation within the cavities. In core-shell configurations, H atoms serve a function analogous to that in He-filled cavities, synergistically interacting with He to induce cavity deformation under mechanical loading.

cond-mat.mtrl-sci

Evolution of cavities in BCC-Fe with coexisting H and He under fusion environments

In the fusion environment, understanding the synergistic effects of transmutation-produced hydrogen (H), helium (He), and irradiation-induced displacement damage in iron-based alloys is crucial for the development of structural materials for fusion reactors. When H and He atoms are simultaneously introduced into the matrix, the interaction between irradiation-induced cavity defects (voids and bubbles) with H and He, along with their evolutionary behavior remains poorly understood. In this study, the evolutionary behavior of cavities in body-centered cubic (BCC) iron (Fe) with H and He atoms is systematically investigated through a combination of molecular dynamics (MD) calculations and statistical thermodynamics. First, an efficient and suitable set of Fe-H-He ternary potential functions for describing interatomic interactions is established. Based on the newly developed MD model, the evolutionary behavior of H/He atoms and cavities is systematically investigated under various temperature and cavity structure conditions. Specifically, the kinetic process of H/He capture by cavities is elucidated for different scenarios. Additionally, thermodynamic analyses are employed to assess the feasibility of cavity trapping of H under varying conditions. The results exhibit strong consistency with experimental results and provide significant evidence supporting the formation of the core-shell structure (where He is confined at the cavity center while H accumulates at the surface) from both kinetic and thermodynamic perspectives. This work provides mechanistic insights into the nucleation and growth of cavities over extended temporal and spatial scales in the presence of H-He synergies.

cond-mat.mtrl-sci

Progress of photonuclear cross sections for medical radioisotope production at the SLEGS energy domain

Photonuclear reactions using a laser Compton scattering (LCS) gamma source provide a new method for producing radioisotopes for medical applications. Compared with the conventional method, this method has the advantages of a high specific activity and less heat. Initiated by the Shanghai Laser Electron Gamma Source (SLEGS), we conducted a survey of potential photonuclear reactions, $(\upgamma,n)$, $(\upgamma,p)$, and $(\upgamma,\upgamma')$ whose cross-sections can be measured at SLEGS by summarizing the experimental progress. In general, the data are rare and occasionally inconsistent. Therefore, theoretical calculations are often used to evaluate the production of medical radioisotopes. Subsequently, we verified the model uncertainties of the widely used reaction code TALYS-1.96, using the experimental data of the \ce{^100Mo}$(\upgamma,n)$\ce{^99Mo}, \ce{^65Cu}$(\upgamma,n)$\ce{^64Cu}, and \ce{^68Zn}$(\upgamma,p)$\ce{^67Cu} reactions.

nucl-ex