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The nanopore characteristics of shale samples from the superdeeply buried Longmaxi Shale (drillcore recovered from 6604−6920 m below ground level), Wufeng Shale (6920−6926 m), and Qiongzhusi Shale (7960−8044 m) were studied from MS Well #1, Sichuan Province, China, which was completed in March 2016 and is the deepest onshore well yet drilled in Asia. To gain a better understanding of the influence of burial depth on the pore system of shales and to aid in the study of nanopore characteristics, the samples were analyzed by FESEM and N 2 gas adsorption. Samples of Sichuan Basin shales recovered from depths ranging from 0 to 5000 m were selected as a control group. The results show similar nanopore characteristics in all 32 superdeeply buried shale samples from the three formations. The dominant pore types in the superdeeply buried shales are organic matter pores and interparticle pores, along with minor intraparticle pores. The dominant pore morphology is slit-like in shape. Low-pressure N 2 adsorption analysis shows that the isotherms of all samples are type IV with an H3 hysteresis pattern. The quenched solid density functional theory (QSDFT) pore size distribution is dominantly in the range of 4−16 nm, and the BET surface area ranges between 8.63 and 16.13 m 2 /g. In comparison with nonsuperdeeply buried shales, superdeeply buried shales in MS Well #1 have a more dispersed pore-size distribution, lower micropore volume and micropore surface area, and higher mesopore volume and mesopore surface area. Thus, the mesopore/micropore volume and mesopore/ micropore surface area ratios of the superdeeply buried shales are several orders of magnitude higher than those of the nonsuperdeeply buried shales. Compaction related to burial depth may compress the pores to reduce the pore sizes and change the pore shapes from round or elliptical-shaped to slit-shaped. Given their relatively small pore sizes, micropores are most easily destroyed during the superdeep burial stage.

A series of coals of varying rank, from brown coal to anthracite, were studied by Fourier transform infrared spectroscopy (FTIR). Curve-fitting analysis was employed to characterize coal structural evolution during the coalification process. The study was carried out on samples of a natural evolutionary series as well as experimental simulation coals dispersed on KBr pellets throughout the Ordos Basin, China. The results showed that the infrared spectrum of coal allowed quality and even quantity identification of the degree of coalification. Oxygen-containing groups and alkyl side chains of coal cracked at different rates with increasing degree of coalification. The cracking rates were divided into three stages according to the main changes in coal structure. These stages were carboxyl groups, fat groups and aromatic rings. Carboxyl groups decreased when R o was less than 0.5%, and these groups were maintained until the fat coal stage began. Fat groups mainly cracked at the asphaltization stage and formed abundant hydrocarbons. These groups were the main sources for the formation of immature and low maturity, coal-generating oil before asphaltization. In the high evolutionary stage, after asphaltization, all alkyl side chains in the coal had cracked, while the degree of condensed aromatic rings had increased greatly. The ratios of aromatic hydrocarbons (3000 to 3100 cm Ϫ1 ) to aliphatic carbons (2800 to 3000 cm Ϫ1 ), CH 2 /CH 3 (2920/2950 cm Ϫ1 ) and carboxyl groups to aromatic carbons (1705/1620 cm Ϫ1 ϩ 1600cm Ϫ1 ϩ 1580 cm Ϫ1 ) appeared to be suitable parameters for assessing the natural maturation of coal.

Homogeneous graphene dispersions with tunable concentrations are fundamental prerequisites for the preparation of graphene‐based materials. Here, a strategy for effectively dispersing graphene using graphene oxide (GO) to produce homogeneous, tunable, and ultrahigh concentration graphene dispersions (>150 mg mL−1) is proposed. The structure of GO with abundant edge‐bound hydrophilic carboxyl groups and in‐plane hydrophobic π‐conjugated domains allows it to function as a special “surfactant” that enables graphene dispersion. In acidic solutions, GO sheets tend to form edge‐to‐edge hydrogen bonds and expose the π‐conjugated regions which interact with graphene, thereby promoting graphene dispersion. While in alkaline solutions, GO sheets tend to stack in a surface‐to‐surface manner, thereby blocking the π‐conjugated regions and impeding graphene dispersion. As the concentration of GO‐dispersed graphene dispersion (GO/G) increases, a continuous transition between four states is obtained, including a dilute dispersion, a thick paste, a free‐standing gel, and a kneadable, playdough‐like material. Furthermore, GO/G can be applied to create desirable structures including highly conductive graphene films with excellent flexibility, thereby demonstrating an immense potential in flexible composite materials.