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Yellow phosphorus slag has been considered as a potential cement substitute for mine filling material due to its cementing activity; however, its slow setting and low early strength have limited broader use. This study investigates the grading, compactness, and strength of yellow phosphorus slag combined with tailing sand. Using yellow phosphorus slag as an aggregate, cement as a binder, and mixing tailing sand in different ratios, this study evaluates its feasibility as a coarse aggregate in mine backfill. The key findings are as follows. (1) The grading index of tailing sand was 0.5, aligning with Fuller grading, but it required mixing with coarse aggregates to enhance strength and reduce cement consumption. Yellow phosphorus slag, with a grading index of 0.97, does not match Fuller's curve and thus benefits from mixing with tailing sand. (2) For mixtures of waste rock and tailings, the 5:5 ratio aligned closely with Fuller's theory, showing optimal packing density and strength. Mixtures of yellow phosphorus slag and tailings at ratios of 3:7, 4:6, and 5:5 had R2 values of 0.73, 0.80, and 0.85, respectively, confirming reliable fit. The 5:5 mixture provided the best packing density and strength. (3) A new strength prediction model, accounting for aggregate, cement, and water effects, suggests that a 5:5 ratio with a 71% mass concentration and 1/7 ash–sand ratio meets industrial strength requirements. FLAC3D simulations indicated that cemented backfill reduces stress concentrations caused by excavation and supports stability during mining while also absorbing energy through compaction, creating favorable conditions for safe mining operations. [ABSTRACT FROM AUTHOR]

Measurement of water content in oil-water mixing flow was restricted by special problems such as narrow measuring range and low accuracy. A simulated multi-sensor measurement system in the laboratory was established, and the influence of multi-factor such as temperature, and salinity content on the measurement was investigated by numerical simulation combined with experimental test. A soft measurement model based on rough set-support vector machine (RS-SVM) classifier and genetic algorithm-neural network (GA-NN) predictors was reported in this paper. Investigation results indicate that RS-SVM classifier effectively realized the pattern identification for water holdup states via fuzzy reasoning and self-learning, and GA-NN predictors are capable of subsection forecasting water content in the different water holdup patterns, as well as adjusting the model parameters adaptively in terms of online measuring range. Compared with the actual laboratory analyzed results, the soft model proposed can be effectively used for estimating the water content in oil-water mixture in all-round measuring range

This paper demonstrated a high-performance hydrogen gas sensor based on CuO-reduced graphene oxide (rGO)-CuO sandwiched nanostructure. The CuO-rGO-CuO nanostructure was examined by scanning electron microscopy, X-ray diffraction and transmission electron microscope. The gas sensing characteristics of the CuO-rGO-CuO film sensor were evaluated at room temperature against hydrogen over a wide concentration range, which are better than that of pristine CuO and rGO. High sensitivity, good repeatability, and response-recovery characteristics were achieved in this work. Furthermore, the possible sensing mechanism of the presented sensor was explored. [ABSTRACT FROM AUTHOR]

This paper demonstrated a resistive-type humidity sensor with hierarchical ZnO/MWCNTs/ZnO nanocomposite film coated. Hydrothermally synthesized ZnO nanorods and functionalized multi-walled carbon nanotubes (MWCNTs) were utilized to construct a humidity sensor by using electrostatic layer-by-layer (ELbL) self-assembly technique. The characterization results including scanning electron microscope and X-ray diffraction confirmed the successful formation of as-prepared nanostructures. The electrical properties of the sensing films were investigated under different deposition time in the ELbL self-assembly process. The humidity sensing behaviors of the ZnO/MWCNTs/ZnO hierarchical hybrid film were investigated in a wide relative humidity (RH) range. It is found that the sensor exhibited an excellent linear response with RH, small hysteresis, acceptable repeatability and swift response-recovery characteristics. The possible sensing mechanism for the presented sensor was attributed to the nanostructure of ZnO/MWCNTs/ZnO and swelling effects between interlayers. This study provided a benchmark for humidity sensor fabrication using ELbL self-assembly technique. [ABSTRACT FROM AUTHOR]