Research on CO Migration Patterns in Shallowly Buried Coal Seam Composite Goafs.

To address the issue of CO exceedance in the close-range composite goaf, this paper focuses on the composite goaf of the Shaping Mine as the research subject and investigated the migration dynamics of CO within shallowly buried composite goaf areas. Sulfur hexafluoride gas (SF) tracer experiments were conducted at the 13103 working face in Shaping Mine to assess surface fissures and air leakage, yielding insights into the distribution patterns of air leakage channels and facilitating the identification of critical areas for channel sealing. Programmed heating and oxidation experiments were conducted on coal seams 8 and 13 to determine the CO generation patterns during coal oxidation.

[Estimated cosmic radiation doses for flight personnel].

Objective. To calculate individual annual cosmic radiation effective dose for monitored flight personnel. Method.