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The Middle Jurassic Walloon Subgroup of Daandine gas field contains numerous coal seams with abundant coalbed methane (CBM) resources. However, the vertical gas content distribution of these coal seams is unclear currently, as well as its influencing factors, affecting the formulation of CBM exploration and exploitation strategy. For this purpose, using diverse geologic, experimental, and engineering data from recent exploration and development, this article ascertains the vertical coalbed gas content distribution in the Daandine gas field and discusses how the geological factors affect it. The results show that the coalbed gas contents have two basic trends as the depth increases: (1) increase, and then decrease; (2) increase. The former trend is dominant, and the inflection point occurs in the coal groups within or close to the Tangalooma Sandstone Formation. The correlation analysis shows that the macerals have little influence on the vertical coalbed gas content distribution. The moisture contents affect the adsorption capacity of coalbeds and show a negative correlation with the gas contents, and coal groups with higher moisture contents generally have lower gas contents. Three sets of independent gas-bearing systems exist in the Walloon Subgroup, and the coalbed gas content-depth relationship is relatively independent among different gas-bearing systems. The better the caprock condition, the higher the gas content, which is particularly evident in the coals of Condamine group. The permeabilities show a significant effect on the coalbed gas contents of Daandine coals. The coal groups within or close to the Tangalooma Sandstone Formation have higher permeabilities, as well as higher gas contents, and they are positively correlated. The reason is that the CBM in the study area is dominantly microbial in origin, and the higher permeability coals are conducive to the introduction of more microbial consortia into the coal seams, enhancing the generation of secondary biogenesis methane. [ABSTRACT FROM AUTHOR]

Gestational diabetes mellitus (GDM) is one of the common complications during pregnancy. Numerous studies have shown that GDM is associated with a series of adverse effects on both mothers and offspring. Due to the particularity of pregnancy, medical nutrition treatment is considered to be the first choice for the treatment of GDM. This contribution reviews the research progress of medical nutrition treatment in GDM, summarizes the international recommendations on the intake of various nutrients and the influence of nutrients on the prevalence of GDM, and the improvement effect of nutritional intervention on it, in order to provide references for research in related fields of GDM and the targeted development of enteral nutrition. [ABSTRACT FROM AUTHOR]

In this study, polydopamine and silver-modified graphene oxide (Ag/PGO) were prepared using a one-step method, and the effects of Ag/PGO as a lubricating oil additive on the viscosity, thermal conductivity, and lubricating performance of lubricating oil were studied. The influence of additive lubricating oil on the temperature increase and vibration of a high-speed motorized spindle was studied through a motorized spindle experiment. The results showed that the addition of Ag/PGO nanocomposites could improve the thermophysical properties and lubricating properties of the lubricating oil. The Ag/PGO nanoparticles deposited on the friction surface formed a friction protective film, which prevented direct contact between the friction pairs and effectively reduced the heat generated through friction and micro-peak collision during bearing operation. The lubricating oil containing Ag/PGO had high thermal conductivity and a good heat dissipation effect in convection heat transfer in the bearing cavity. The deposition and repair of nanoparticles could improve the micro-morphology of the friction surface and reduce the high-frequency amplitude of the motorized spindle. [ABSTRACT FROM AUTHOR]