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During and after the in-situ mining of anthracite coalbed methane, the influence of temperature on anthracite coal has become an important factor in judging whether a project can be implemented. In this paper, the stress-strain curves of anthracite at 10 MPa hydrostatic pressure and different temperatures, stress-strain curves at 300 ℃ and different hydrostatic pressures, the stress-strain curves of anthracite under different hydrostatic pressures under temperature rise of 500 ℃ and then slow cooling to 300 ℃, were studied by using the servo experiment device independently developed by the Key Laboratory of In-situ Modified Mining of Ministry of Education, Taiyuan University of Technology. The results show that during the process of heating up, anthracite exhibits different thermal expansion laws under different hydrostatic pressure conditions. The greater the hydrostatic pressure, the smaller the thermal deformation; as the temperature increases, the elastic modulus and peak strength of anthracite will decrease accordingly; the confining pressure will enhance the strength of anthracite, which is specifically expressed in that with the increase of hydrostatic pressure, the elastic modulus and peak strength of anthracite will increase; the weakening effect of high temperature on anthracite is irreversible. The performance is that when anthracite is directly heated to 300 °C, the cohesion and internal friction angle of the two are different from that of anthracite when the temperature is raised 500 °C and then lowered to 300 °C. This paper uses orthogonal experiments to fit the elastic modulus of anthracite within 15 MPa and 300 ℃ as a function of confining pressure and temperature.

Datong long-flame coal from China was pyrolysis with superheated water vapor at 300°C to 536°C. Chemical and physical changes of long flame coal, including composition, weight loss, pore fracture structure, density, and water absorption were tested, and the qualitative and quantitative relationships among these changes were analyzed. superheated water vapor pyrolysis removes moisture and volatile components from long flame coals and increases the fixed carbon content. After superheated water vapor pyrolysis, the O/C and H/C atomic ratios of long flame coal decreased due to the decomposition of oxygen-containing functional groups and chain aliphatic hydrocarbons. superheated water vapor pyrolysis increased the porosity of long flame coal by material removal and matrix fracture. Material removal occurs throughout the pyrolysis process but matrix fracture occurs only at the initial stage of the conversion of solid organic matter to oil and gas products. The expansion of pore fractures in long flame coal caused a significant decrease in apparent density and an increase in water absorption. Quantitative analysis revealed the forced water absorption of long flame coal was quadratically polynomial with respect to porosity. [ABSTRACT FROM AUTHOR]

Purely organic emitters that can efficiently utilize triplet excitons are highly desired for organic light‐emitting diodes (OLEDs). Hot exciton channel has emerged as a competitive strategy for the efficient harvest of triplet exciton to improve the OLEDs performance and suppress efficiency roll‐off in devices. Here, two deep blue emitters, OPACN and SPACN are designed and synthesized, employing diphenylanthracene (PAnP) unit as central core, sp3 hybridized O and S atom as conjugation blocker, and electron‐withdrawing cyano group as intramolecular charge transfer (ICT) introducer. Especially, OPACN presents bluer emission with electroluminescence (EL) peak at 436 nm, CIE coordinates of (0.16, 0.10), and a maximum external quantum efficiency (EQE) of 8.7%, while SPACN shows an EL peak at 444 nm, CIE coordinates of (0.17, 0.12) and a maximum EQE of 9.0%. Furthermore, the single‐component white organic light‐emitting diode (WOLED) based on OPACN exhibits dual emission from monomer and excimer with EQE of 5.4%. And even the luminance increases to 1000–10 000 cd m−2, the EQE still remains as high as 5.2% and 4.4%, respectively, showing very low efficiency roll‐offs. These results demonstrate an alternative approach for designing high‐performance deep blue OLEDs and WOLEDs based on single component. [ABSTRACT FROM AUTHOR]