Hunan University of Science and Technology

Liu C., Huang Z., Wang X.

Ding H., Wen G., Long Q., Wu J., Chen Y.

As mining depths increase, the highly metamorphosed anthracite in Southwest China progressively develops into a complex dynamic disaster influenced by both in situ stress and gas pressure. By utilizing characteristic indicators of mining-induced stress and gas dynamic emissions, a grading evaluation method for coal and gas dynamic disasters (CGDDs) based on fuzzy mathematics l theory is proposed and validated at the No. 1 Well of the Yuwang Coal Mine. The results indicate that the acceleration of microseismic wave velocity and the increase in the wave velocity anomaly coefficient are indicative of a more pronounced stress concentration. The working face exhibits distinct gradations of stress concentrations, categorized as weak, moderate, and strong. Moreover, the increase in microseismic wave velocity and the anomaly coefficient further confirm the intensity of the stress concentrations. Gas dynamic emissions show a clear correlation with the drill cuttings gas desorption indicator (K1 value) and drill cuttings volume (S value). Characteristic indicators A, B, and D are suitable for assessing the risk of CGDDs in the working face. For the application of individual indicators for classifying the CGDD risk at different distances from the crosscut (128 m, 247.5 m, 299.4 m, and 435 m) in the 1010201-working face, contradictory classification results were observed. However, the classification results derived from the fuzzy mathematics method were consistent with the findings of field investigations. As the working face advanced through the pre-concentrated stress zone, significant changes were observed in both the source wave velocity and wave velocity anomaly coefficient. Concurrently, gas emissions displayed a distinct pattern of fluctuation characterized by increases and decreases. The consistency between the periodic weighting of the working face, the gas emission, the drill cuttings gas desorption indicator, and the stress field inversion result further validates the classification outcomes. These research results can provide theoretical support for the monitoring of CGDDs.

Liu S., Shen H., Yu Q., Lu C.

Li H., Wu X., Liu H., Hong Y., Zou Q., Lu J., Mou J.

Peng Y., Wen Z., Ren B., Zhu G., Zhou S., Deng R.

Abstract: In recent years, the substantial influx of heavy metal pollutants into aquatic environments due to human activities has emerged as a critical issue. Heavy metals are characterized by their high toxicity, persistence, and resistance to degradation, which not only result in significant economic losses but also exert severe impacts on ecosystems and human health. Microalgae, due to their adsorption capacity for heavy metals, have become a new avenue for the biological remediation of heavy metal pollution in aquatic environments. With the advantages of low cost, renewability, environmental friendliness, and strong adaptability, microalgae showed broad application prospects in the management of heavy metal pollution. This manuscript provides a comprehensive review of microalgae- based remediation of heavy metal pollution in aquatic environments. It examines the factors influencing heavy metal adsorption by microalgal cells, compares the adsorption capacities of different algal species, and evaluates the adsorption effectiveness of live versus dead algal cells. The review also summarizes the mechanisms of heavy metal accumulation and transfer in microalgae and identifies future research priorities and directions for enhancing the heavy metal enrichment capabilities of microalgae.

Rao K., Yan H., Yang P., Wang M., Chen C.

Chen L., Xu Y., Li M., Hu B., Guo H., Liu Z.

Zhong Z., Jiang H., Wang H., Liu Y.

Physical and psychological distress frequently challenges athletes throughout their careers. The perception of pain and coping strategies are often crucial factors in achieving victory. These factors not only reflect their commitment to daily training, but can also indicate their level of athletic performance. This study is a cross-sectional research using convenience and snowball sampling methods. It explores the relationship between mindfulness and athletes’ distress tolerance, revealing the mediating roles of cognitive reappraisal and mental toughness. A sample of 285 athletes was drawn from universities, youth training centers, and sports academies in Hunan, Hubei, and Sichuan provinces in China. To assess the proposed hypotheses, structural equation modeling was conducted using AMOS v23. The findings identified a significant positive correlation between mindfulness, cognitive reappraisal, and mental toughness. Additionally, both cognitive reappraisal and mental toughness were positively associated with distress tolerance. Further analysis demonstrated that cognitive reappraisal and mental toughness function as mediators in the mindfulness–distress tolerance relationship. These results indicate that athletes with higher mindfulness levels exhibit enhanced cognitive reappraisal skills, greater mental toughness, and improved distress tolerance. This means that athletes with higher mindfulness levels are more likely to detach from negative psychological states in a timely manner, utilizing emotional regulation skills such as cognitive reappraisal, and face training and competition with greater mental resilience. This can help athletes alleviate negative psychological states and, to some extent, reduce their experience of pain, enabling them to better cope with challenges. Therefore, athletes can actively engage in mindfulness practices combined with cognitive reappraisal strategies to achieve better psychological states, which can support their adherence to training and rehabilitation plans.

Wen J., Li X., Xie K., Liang W., Xie G.

Lin Q., Li X., Xie K., Wen J., He S., Xie G., Fan X., Feng Q.

Zhao K., Li Y., Pei R., Li H., Bennett G.J.

Turbulent boundary layer wall pressure fluctuations are of significant concern in acoustic engineering for both high-speed airborne and underwater vehicles, and the modeling of the associated wavenumber-frequency spectra has been extensively studied. In this paper, a review of 12 models developed between 1964 and 2017 has been conducted, and both the 2D and 1D forms investigated. In this work, fundamental concepts are introduced, followed by a classification of the models into two categories, that is, Corcos-type and non-Corcos-type models. Both the 2D and 1D forms of the 12 models are individually introduced in chronological order. To evaluate these models, comparisons of the 2D and 1D wavenumber-frequency spectra at different speeds and frequencies were conducted. Unlike Corcos-type models, non-Corcos-type models are grounded in a stronger theoretical foundation, with some models accurately reflecting acoustic region characteristics. Corcos-type models exhibit good consistency, however, they require an auto-spectrum as a necessary input, which makes them semiempirical models. In addition, the models within the Corcos-type and the non-Corcos-type were also compared, respectively, and a few important conclusions were accordingly made. The research output from this paper can provide an important practical engineering reference for studies associated with acoustic engineering, such as aircraft cabin noise and submarine hydrodynamic noise.

Peng L., Yang C., Yang J., Tu Y., Yu Q., Li Z., Chen M., Liang W.

Xie K., Liu C., Wang X., Li X., Xie G., Wen J., Li K.

Han H., Zhou Z., Shang T., Li S., Shen X., Fang J., Cui L.

Yang X., Du C., Liu X., Sun L.