Rockburst is a difficult problem in underground resource development and infrastructure construction. With scientific and technological progress, more research technologies and methods to prevent rockburst have been proposed and applied. Research content has become more comprehensive, and positive progress and achievements have been made. However, due to the complexity of rockburst control factors and the sudden occurrence of rockburst, the occurrence mechanism and accurate prediction of occurrence intensity and time are still difficult worldwide problems. In this paper, the research development and achievements of rockburst are reviewed. Firstly, various definitions and types of rockburst are briefly summarized. Then, research progress and achievements in four aspects are comprehensively reviewed, including methods and techniques of rockburst research (theoretical research, numerical simulation, physical model tests and in situ monitoring), mechanism of rockburst, classification and prediction of rockburst (empirical criteria, in situ monitoring, mathematical model approaches and rockburst chart) and prevention and control of rockburst. Of particular significance is that the classification and prediction with prevention and control are summarized in detail. Finally, limitations, deficiencies and some promising directions for future research are listed.

This paper attempts to use a kind of smart material-magnetorheological fluid and magnetorheological jet polishing method to polish mould. Use self-preparation MR fluid conduct experiments on MR jet polishing setup which developed by ourselves. After polished by MR jet, surface roughness of the mould improved from 812nm to 88nm. The result shows that experiment and its setup are feasible.

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There are high- and low-frequency noise signals in a microseismic signal that can lead to the distortion and submersion of an effective waveform. At present, effectively removing high- and low-frequency noise without losing the effective signal of local waveform spikes remains a challenge. This work addresses this issue with an improved wavelet adaptive thresholding method. Because a denoised signal conceptually approximates the minimum error, a dynamic selection model is established for the optimal threshold. On this basis, an adaptive correction factor aj is proposed to reflect the noise intensity, which uses the 1/2 power of the ratio of the median absolute value to the amplitude of the monitoring data to reflect the noise intensity of the wavelet detail signal and corrects the size of the denoising scale. Finally, the performance of the improved method is quantitatively evaluated in terms of the denoising quality and efficiency using the signal-to-noise ratio, root-mean-square error, sample entropy and running time.

In this paper, high-purity porous calcium hexaluminate materials were prepared with α-alumina, nano-meter calcium carbonate and ρ-alumina as raw materials. The properties of the prepared porous materials, such as bulk density, true density, thermal conductivity, and cold crushing strength, were investigated. The increase in sintering temperature led to the increase of true density. Bulk density and cold crushing strength of the specimen fired at 1500°C had the lowest values. As ρ-alumina content increased, bulk density, true density, and cold crushing strength had no obvious changes, but the thermal conductivity decreased at first and then increased. The calcium hexaluminate formation was intense from 1450°C to 1500°C and finished at 1500°C. Above 1500°C, the main phase of specimens was calcium hexaluminate (CA6). And CA6 grains were regular hexagonal plates morphology and widely spread after firing at 1550°C.

The investigation on the interaction mechanism between pesticide pyriproxyfen (PPF) and serum albumin has great implications in clinical detection, gene mutation and pathological analysis of pesticide poisoning. In this paper, the binding behavior of PPF with bovine serum albumin (BSA) have been assessed through various spectroscopic techniques combined with computer simulation. The findings confirmed that PPF quenched the endogenous fluorescence of BSA in the means of static quenching and formed the stable PPF‐BSA complex with the stoichiometry of 1:1. The affinity of PPF on BSA was moderate due to its binding constant of 4.15×103 M−1 (298 K). It was confirmed from replacement experiments and molecular docking that PPF bound preferentially onto the Site I region of BSA. The findings from thermodynamic parameter analysis and the replacement experiments of ANS and sucrose confirmed the driving‐forces for forming PPF‐BSA complex was hydrogen bonding, van der Waals and hydrophobic interactions. Meantime, it was also confirmed from synchronous fluorescence and FT‐IR spectra that the hydrophilicity surrounding Trp residues and α‐helix of BSA declined due to binding with PPF. And, it is confirmed from in silico finding the dipole moment, atomic charge distribution, molecular conformation, and frontier orbital of PPF also significantly altered after binding with BSA.