Ordos Basin is an important continental shale gas exploration site in China. The micropore structure of the shale reservoir is of great importance for shale gas evaluation. The Taiyuan Formation of the lower Permian is the main exploration interval for this area. To examine the nanometer pore structures in the Taiyuan Formation shale reservoirs in the Lin-Xing area, Northern Shaanxi, the microscopic pore structure characteristics were analyzed via nitrogen adsorption experiments. The pore structure parameters, such as specific surface area, pore volume, and aperture distribution, of shale were calculated; the significance of the pore structure for shale gas storage was analyzed; and the main controlling factors of pore development were assessed. The results indicated the surface area and hole volume of the shale sample to be 0.141–2.188 m²/g and 0.001398–0.008718 cm³/g, respectively. According to the IUPAC (International Union of Pure and Applied Chemistry) classification, mesopores and macropores were dominant in the pore structure, with the presence of a certain number of micropores. The adsorption curves were similar to the standard IV (a)-type isotherm line, and the hysteresis loop type was mainly similar to H3 and H4 types, indicating that most pores are dominated by open type pores, such as parallel plate-shaped pores and wedge-shaped slit pores. The micropores and mesopores provide the vast majority of the specific surface area, functioning as the main area for the adsorption of gas in the shale. The mesopores and macropores provide the vast majority of the pore volume, functioning as the main storage areas for the gas in the shale. Total organic carbon had no notable linear correlation with the total pore volume and the specific surface area. Vitrinite reflectance (Ro) had no notable correlation with the specific surface area, but did have a low “U” curve correlation with the total pore volume. There was no relationship between the quartz content and specific surface area and total pore volume. In addition, there was no notable correlation between the clay mineral content and total specific surface area and total pore volume.

The chemical compositions of most lunar impact glass beads reflect mixing of crustal components including mare basalts, highlands rocks, and KREEP [from high concentrations of K, REE (rare earth element), and P]. However, a few glass beads in the soil from the Chang’e-5 mission have unusually high MgO contents that require distinct target compositions. The young age of these high-MgO glass beads suggests an origin through impact melting of ultramafic target rocks with abundant pyroxene and olivine. While such targets might represent cumulates of mare basalts, impact melts, or Mg-suite rocks, they appear unlike any sampled lunar lithologies. Alternatively, these high-Mg beads might be sampling the upper mantle brought to the surface by the Imbrium basin–forming event.

The spatial distribution, sources and ecological risk of 16 US EPA priority polycyclic aromatic hydrocarbons (PAHs) in surface soil from Liuxin area, Xuzhou, China was investigated in this study. Gas chromatography-mass spectrometry analysis revealed ΣPAH concentrations ranging from 115.66 to 373.53 ng ⋅ g ⁻¹ (mean: 196.26 ng ⋅ g ⁻¹ ), with phenanthrene (Phe) exhibiting the highest mean concentration (51.18 ng ⋅ g ⁻¹ ). Spatial analysis demonstrated a southeast-to-northwest concentration gradient, with maximum PAH levels observed in southeastern zones. PAH composition showed dominance of low-molecular-weight species (2, 3 rings: 46.7%), followed by 5, 6 ring PAHs (28.3%), and 4-ring compounds (24.9%). Source apportionment using molecular diagnostic ratios and positive matrix factorization identified four primary contributors: coal-fired power generation & metallurgical emissions (34%), biomass combustion (31%), diesel fuel combustion/leakage (29%), traffic emissions (6%). Ecological risk assessment employing Dutch soil quality standards revealed localized exceedances in southeastern areas, particularly for fluoranthene (Fla) and Phe. However, toxic equivalency quotients remained low, with incremental lifetime cancer risks below 10 ⁻⁶ for all exposure pathways. These findings indicate that while PAH contamination warrants monitoring, current levels pose negligible carcinogenic risk to the local population.