Matrix compressibility and pore properties (pore size distribution) of a rank range of coals was investigated using mercury intrusion porosimetry (MIP) on coal cores with the pore size distribution also being determined using low temperature at 77 K nitrogen adsorption/desorption isotherms for crushed samples. The coal matrix compressibility is significant when the pressure of MIP is from 0.0074-35 MPa. Mathematical models were developed (based on MIP and nitrogen adsorption/desorption isotherms) to establish the porosity/pore size distribution relationships with matrix compressibility. For coal ranks, the matrix compressibility was between 0.2410-4 to 13.5610-4 MPa-1 , and had a negative exponential relationship with the vitrinite reflectance (R o,m %). Lignites have the maximum matrix compressibility due to their structural open structure having limitied compaction during coalification. In addition to the pore structure relationship the composition, moisture, and ash yields impacts on compressibility were also examined. Inertinite-rich coals however had a low matrix compressibility across the rank range, which may be due to the interinhibitive relationships between the mesopores, macropores and minerals. The wetting action of high moisture (water molecules) weakens the link between the coal particles of the lignites and the subbituminous coals, which causes abnormally high compressibility. Observations here relate to hydrofracturing or CO 2 injection behaviors during enhancing coalbed methane (CBM) recovery.

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Yacheng Formation has been divided into one cycle sequence of ultra longperiod, three cylce sequences of long-period and 12 cycle sequences of intermediate period based on data from comprehensive drilling cores, logging, the seismic survey and former studies. Every sequence and its interface have the corresponding response in lithology, facies, logging, and earthquake data. The development and transformation of the base level cycle of intermediate period in Yacheng Formation were controlled by the tectonic subsidence and the global sea level eustacy. Because the rising rate of the tectonic subsidence was obviously higher than that of the global sea-level. The dominating action of the tectonic subsidence was more obviously on the base-level cycle. The coal formation of Yacheng Formation was mainly caused by gelatination. The coal seams were mainly developed in the peat swamp of the delta plain of braided river and the upper intertidal zone and the supralittoral zone of tidal plat. In the early period of Yacheng Formation, the main coal-forming systems was mainly the braided river-braided river delta system, while in the late period, it was mainly the tidal plat-lagoon system.

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As an important organ to maintain the host's homeostasis, intestinal microbes play an important role in development of the organism. In contrast to those of terrestrial animals, the intestinal microbes of aquatic organisms are affected by environmental microorganisms (including water microorganisms and sediment microorganisms). In the present study, the compositional differences of intestinal microbes in three representative developmental stages of the Chinese mitten crab ( Eriocheir sinensis ) were studied. Meanwhile, network association analysis, and visualization of the water microorganisms of the crabs’ habitat, the environment microorganisms in the pond, and the intestinal microbes, was carried out. The results showed that the gut microbiota diversity index decreased continuously with age, and the four bacteria of Aeromonas (Proteobacteria), Defluviitaleaceae (Firmicutes), Candidatus Bacilloplasma (Tenericutes), and Dysgonomonas (Bacteroidetes) were the “indigenous” flora of the crab. In the network‐related analysis with the environment, we found that as the culture time increased, the effect of environmental microorganisms on the intestinal microbes of crabs gradually decreased, and the four “indigenous” bacteria were always unaffected by the environmental microorganisms. The results of this study identified the core bacteria of the crab and, for the first time, studied the relationship between intestinal environmental microorganisms, which will aid the practical production of crabs and will promote research into the relationship between specific bacteria and the physiological metabolism of crabs.