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The fatigue life and cutting performance of conical pick is essential for the roadheader machine in the excavation engineering. In rock breaking process, the rock structural conditions has a certain influence on the rock breaking and rock damage with roadheader breaking rock. Established the simulation model of conical pick cutting jointed rock to investigate the influence of the rock joint, rock bedding and confining pressure on the cutting performance and fatigue life of conical pick and rock damage. And the MATLAB is applied to solve the difficulty of rock damage statistical analysis. The research results indicated that the cutting force decreases with the rock joint length increasing, the cutting force increases first and decreases with the rock bedding angle increasing, however, the cutting force decreases first and then increases with the confining pressure increasing. The rock damage has a great relationship with the rock joint, rock bedding and confining pressure. The rock damage increases first and decreases then with the rock joint increasing and the rock bedding angle increasing. However, the influence of confining pressure on rock damage is contrary. Meanwhile, the rock fracture volume is positively correlated with damage value. The research results indicated that the rock structural parameters have an obvious influence on conical pick cutting performance and rock damage. [ABSTRACT FROM AUTHOR]

In this paper, by a simple hydrothermal method vertically aligned ZnO nanorod arrays were grown on the carbon fiber paper (CFP) and then through a facile chemical bath deposition method CuO nanosheets were loaded on ZnO nanorod arrays, following by thermal spraying method, carboxylated carbon nanotubes (CCNTs) were successfully integrated with CuO/ZnO@CFP to form a binder-free CuO/ZnO-CCNT@CFP sensor. The sensor shows enhanced sensing activity for baicalein and luteolin determination due to the improved structural integration and synergism of different electrode material components. Remarkably, the CuO/ZnO-CCNT@CFP sensor showed good linear relationships over wide concentration ranges of 0.03–0.70 µM and 0.70–20 µM for baicalein and 0.03–0.45 µM and 0.45–8.5 µM for luteolin detection, with the detection limits of 1.7 nM for baicalein and 0.5 nM for luteolin, respectively. More importantly, the CuO/ZnO-CCNT@CFP sensor was utilized in the simultaneous determination of baicalein and luteolin, delivering linear ranges of 0.4–14 µM (baicalein) and 0.2–6 µM (luteolin) with the limit of detection of 0.05 µM and 0.03 µM, respectively. In addition, the developed CuO/ZnO-CCNT@CFP electrode was further investigated to detect baicalein and luteolin in traditional herbal medicine samples, showing satisfied results in comparison with analytic results from high performance liquid chromatography. [ABSTRACT FROM AUTHOR]