Study on roof movement law of local filling mining under peak cluster landform.

The strip structure filling mining technology is suggested in response to the environmental issues such as surface subsidence and landslides brought on by the mining of 11,071 working faces in a mine in Guizhou. The mining technology system is studied through indoor testing, numerical simulation, and engineering monitoring. According to theoretical study, the filling strip can be steadily loaded and its value doesn't exceed 10 m when the width of the filling strip and the width of the filling interval are set to be equal. According to laboratory testing, fly ash can replace some of the cement in the cement mixture as a binder to maintain strength while cutting costs. The degree of crystallization gradually distributed into the network in the filling paste of various ages corresponds to its strength when combined with the findings of scanning electron microscopy; The numerical simulation results show that the maximum subsidence of the immediate roof is reduced from 340 to 3 mm from the filling rate of 0 to 100%, the filling effect is remarkable, and the shape of the settlement curve is changed from 'U' to 'basin', then to 'W'; during the local filling mining, the settlement curve of the immediate roof presents a 'wave' shape, and the stress curve of the immediate roof in the middle of the stope is also changed. The peak tension of the coal wall falls synchronously with filling spacing on both sides of the stope. The overall vertical stress below the mountain is larger, and the vertical stress at the top of the filling body eventually shifts from a "saddle" shape to a "inverted U" shape without zero support stress. In conjunction with the plastic zone, it is discovered that the stable bearing of the "filling strip-direct roof" composite structure increases with decreasing tensile and shear damage range of the hollow roof area and both sides of the top of the "filling 3 m interval 3 m" scheme; engineering measurement also reveals that the higher the position of the survey line is, the smaller the displacement is. However, the overall displacement of the strata directly above is negligible, and the greatest displacement is only 10.9 mm, which is consistent with the numerical simulation. At the same time, the displacement beneath the mountain area is too great.

Bilateral Pulmonary Enteric Adenocarcinoma on FDG PET/CT.

ABSTRACT: Pulmonary enteric adenocarcinoma(PEAC) is a rare variant of pulmonary adenocarcinoma. We herein report FDG PET/CT findings of PEAC in a 76-year-old woman. The images showed widespread opacities in both lungs with intense FDG uptake. The pathology revealed pulmonary enteric adenocarcinoma.

Effect of Sasobit/Waste Cooking Oil Composite on the Physical, Rheological, and Aging Properties of Styrene-Butadiene Rubber (SBR)-Modified Bitumen Binders.

The modifying effects of polymer on bitumen low-temperature performance are substantially compromised by the thermal breakdown of styrene-butadiene rubber (SBR) polymer during bitumen mixture production operations. The efficacy of the utilization of Sasobit/waste cooking oil (Sasobit/WCO) as a warm-mix additive has been demonstrated in mitigating the adverse consequences of thermal aging on SBR-modified bitumen binder (SB) while preserving the binder's original performance characteristics. However, few studies have been conducted to further investigate the rheological properties and aging resistance of SB modified with Sasobit/WCO compounds. In this work, three additives-Sasobit, WCO, and Sasobit/WCO composite-were selected, and their effects on the physical and rheological characteristics of SB as well as the temperatures at which the mixtures were prepared were assessed. In addition, by using dynamic shear rheometers (DSR) and bending beam rheometers (BBR), the effects of this innovative warm-mix addition on the performance grade (PG) and aging resistances of SB were evaluated. According to the results, Sasobit/WCO composites outperform Sasobit and WCO in lowering the mixture preparation temperature. Sasobit/WCO also improves both the high- and low-temperature performance of SB simultaneously. Compared to hot-mix asphalt mixtures, the addition of Sasobit/WCO reduces the preparation temperature of the bitumen mixtures by 19 °C, which in turn helps to minimize the negative effects of temperature aging on the functioning of the SB. Additionally, the Sasobit/WCO composite addition can improve the SB mixture's resistance to thermal cracking. After the introduction of Sasobit/WCO, the high-temperature PG of SB was raised by two levels, regardless of whether the warm-mix impact was taken into account. With the addition of Sasobit/WCO, SB's resilience to short-term aging was enhanced.