The microscopic pore structure is of great significance to the study of concrete materials. However，the traditional pore structure testing methods， such as nuclear magnetic resonance (NMR)，mercury intrusion porosimetry (MIP)，optical microscopy，X-ray tomography (X-CT)，and nitrogen adsorption，still have some limitations in terms of pore morphology and nanoscale pore characterization. In this study，we proposed to use argon ion polishing-scanning electron microscopy method to study the microscopic pore structure in concrete，prepared concrete samples with high-quality mechanically damage-free surfaces， and qualitatively investigated four types of pore structure in concrete. Large-area backscattered electron images were collected, and the pore porosity，pore diameter，pore shape factor，and graded porosity of the pore structure were quantified by ImageJ，Avizo，and other software. This method achieves the qualitative analysis and quantitative characterization of concrete microporous structure, which is of reference significance for the research and analysis of the microstructure of concrete materials.

A year-long investigation of air radon concentration at Beishan URL site and its surrounding areas was carried out using solid-state nuclear track detectors at 24 points，with quarterly sampling and measurements conducted. The results indicated that the annual radon concentration in the region ranged from 10 to 64 Bq·m^-3，with a geometric mean (GM) of 27 Bq·m^-3. The overall radon levels exhibited distinct seasonal variations, with the highest concentrations occurring from April to June and the lowest from January to March. The differences in radon concentrations between different areas were small and remained relatively stable. Construction disturbances in the active construction zones had a localized impact on radon concentrations，but due to favorable air diffusion conditions，this effect did not result in a widespread increase in radon levels. This suggests that the direct impact of human activities on regional radon concentrations is limited. According to the Pearson correlation coefficient analysis，a significant positive correlation was observed between temperature and radon concentrations，with radon levels increasing as temperatures rose at most measurement points. In contrast，the influence of wind speed on radon concentrations was more complex，with considerable variability in correlation across different points，likely influenced by other factors，warranting further investigation. This study provides data support and practical insights for long-term radon monitoring and health risk assessment at the Beishan URL.

Delingha depression in the eastern Qaidam basin is believed a potential area for sandstone type uranium deposit in the target stata of the Neogene Shizigou formation and the Shangyoushashan formation. The in-depth investigation on the sedimentary facies characteristics and evolution of strata will provide valuable guidance for uranium exploration. Detailed observations of lithofacies assemblages and sedimentary formation in field outcrops，drilling cores, and well logging analyses have identified that the alluvial fan-braided river delta-lake are the dominant sedimentary facies type in the study area. Among these，the distributary channels in the braided river delta plain and subaqueous distributary channels in the braided river delta front are well-developed with significant scale and good connectivity，providing a favorable sedimentary environment for uranium enrichment. This new understanding has contributed to the knowledge of the spatial and temporal distribution of sand bodies in the Shizigou formation and the Shangyoushashan formations in the eastern Qaidam basin，and provided key information in guiding the future prospecting and exploration.