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This research is designed to investigate the variations in ultrasonic p-wave velocity in various coal based paste fill materials used for recovering standing pillars in closed/closing coal mines, with consideration given to the effects of numerous material-related factors. For this purpose, orthogonal tests were designed. The evaluation was performed on the effects of four variables on the ultrasonic p-wave velocities in samples, using coal grains as the primary material. These variables consisted of the coal grains' particle size (PA), high-water material content (PB), cement content (PC), and water content (PD). The experimental results show the following: (1) Ultrasonic p-wave velocity of coal based paste fill materials are measured within the range of 1.596 to 2.357 km/s, and these are classified (in descending order) as PD, PB, PC, and then PA, based on their effects on ultrasonic p-wave velocity. (2) Ultrasonic p-wave velocity is positively correlated with compressive strength and shear strength; the correlation coefficients are 0.82 and 0.69, respectively. (3) Changes in the ultrasonic p-wave velocity of coal based paste fill materials, when exposed to various factors, have been characterized by fitted formulae. It was observed that the velocity maintained a quadratic polynomial correlation with factor PB and exponential correlations with factors PA, PC, and PD. The comprehensive predictive model, reflecting the characteristics of the ultrasonic p-wave velocity in response to the combined influence of these four factors, was developed through the utilization of fitted equations pertaining to individual factor variations. Subsequently, this model underwent verification. [ABSTRACT FROM AUTHOR]

the study is used by the co-precipitation method to make some uniform particle size and have good Fe3O4 magnetic nanoparticles and their surface modified with oleic acid ; oleic acid as the carrier of Fe3O4, quercetin as template molecule, prepared by the microwave assisted molecular imprinted polymer magnetic nanospheres; In raspberry ethyl acetate extract fingerprints for the assessment index, with orthogonal design best preparation; Characterization of equilibrium adsorption constant Kd and maximum adsorption capacity Qmax by Scatchard model.The results show that: This study explores the preparation of MIPs polymerization time by ten times, prepared by the Fe3O4 nanometer level, greatly increase the MIPs of the specific surface area, thereby increase the amount of adsorption (Kd = 0.7322mg / L, Qmax = 18.92μmol / g). Successfully extract raspberry flavonoids active ingredients from ethyl acetate which can be used for rapid and large parts of ethyl acetate enrichment raspberry flavonoids.

Meiosis plays an essential role in the production of gametes and genetic diversity of posterities. The normal double-strand break (DSB) repair is vital to homologous recombination (HR) and occurrence of DNA fragment exchange, but the underlying molecular mechanism remain elusive. Here, we characterized a completely sterile Osmfs1 (m ale and f emale s terility 1) mutant which has its pollen and embryo sacs both aborted at the reproductive stage due to severe chromosome defection. Map-based cloning revealed that the OsMFS1 encodes a meiotic coiled-coil protein, and it is responsible for DSB repairing that acts as an important cofactor to stimulate the single strand invasion. Expression pattern analyses showed the OsMFS1 was preferentially expressed in meiosis stage. Subcellular localization analysis of OsMFS1 revealed its association with the nucleus exclusively. In addition, a yeast two-hybrid (Y2H) and pull-down assay showed that OsMFS1 could physically interact with OsHOP2 protein to form a stable complex to ensure faithful homologous recombination. Taken together, our results indicated that OsMFS1 is indispensable to the normal development of anther and embryo sacs in rice. [ABSTRACT FROM AUTHOR]