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Major explosive volcanic eruptions were important triggers of abrupt climate changes during the Holocene and crucial sources of Hg to the atmosphere, yet there remains limited understanding regarding the long‐range transportation of this volcanic Hg and its imprint in natural archives. Here, we present a reconstruction of Holocene global volcanism based on the anomalies in Hg concentrations, accumulation fluxes, and Hg/C ratios in three high‐resolution peat profiles spanning Eurasia. Our reconstruction reveals that the two Tibetan peat profiles recorded 33 major explosive volcanic eruptions (with 11 eruptions being synchronously detected), which correspond with a French Pyrenees peat record and sulfate anomalies in polar ice cores. Additionally, the major explosive volcanic eruptions recorded in the TP peat profiles coincided with abrupt decreases in solar irradiance during the Holocene, suggesting these eruptions might have had a greater global climate impact. Our results suggest the atmospheric transport of volcanic Hg within the Northern Hemisphere and underscore the significant role played by major explosive volcanic eruptions in precipitating abrupt global climate and environmental changes during the Holocene. This study has implications for deciphering the configuration of volcanic eruption seasons, locations, and magnitudes during the Holocene and aligning the chronology of peat deposits with ice cores. Plain Language Summary: Major explosive volcanic eruptions, one of the principal geogenic sources of Hg to the atmosphere, are widely acknowledged as significant drivers of abrupt global environmental and climate changes during the Holocene. While the magnitudes and timing of these eruptions have been well documented in ice core records, the long‐range transportation of the volcanic materials (such as Hg and SO2) and their terrestrial dispersion remain largely unknown. In this study, we present a reconstruction of Holocene global volcanism based on the anomalies in Hg concentrations, accumulation fluxes, and Hg/C ratios in three high‐resolution peat profiles, with two collected from the Tibetan Plateau and one from the French Pyrenees. Our reconstruction reveals that the Tibetan peat profiles recorded 33 major volcanic eruptions, which correspond with a French peat record and the sulfate anomalies in polar ice cores. Additionally, we demonstrate that certain major explosive volcanic eruptions likely triggered several abrupt decreases in solar irradiance during the Holocene. Our findings suggest the convective atmospheric transport of volcanic Hg within the Northern Hemisphere extratropical region and underscore the significant role played by major explosive volcanic eruptions in precipitating abrupt global climate and environmental changes during the Holocene. Key Points: Eleven major explosive volcanic eruptions during the Holocene were synchronously recorded in two peat profiles in the Tibetan PlateauThe recorded major explosive volcanic eruptions coincide with nine abrupt decreases in solar irradiance during the HoloceneThe Hg anomalies in peat profiles have the potential to be chronology markers that were linked with volcanic eruptions [ABSTRACT FROM AUTHOR]

Aiming at the problem of mechanical seal failure due to serious wear and tear in operation, the numerical model of the thermal–solid coupling wear of the seal ring is established by taking the friction sub-material as the research object, and the hardness, wear coefficient, and friction coefficient of different soft-ring materials are obtained by a test to verify the accuracy of the numerical model of wear. Additionally, the temperature field and deformation field of the seal ring of different materials are calculated, and the effects of the material parameters, such as elasticity modulus and thermal conductivity, on the temperature, relative deformation, and axial deformation trend are reported. The wear relation of the mechanical seal was optimized, and the correction coefficients of several materials were calculated. The results show the following: the main wear of the seal ring is due to adhesive wear leading to particle shedding and extrusion, adhesive wear causes material transfer, which alters the composition of the worn surface.in turn leading to cratering, which also causes the wear of the seal ring; the friction performance is better when the soft-ring material is graphite (C); the temperature, as well as the deformation, is smaller when the soft-ring material is silicon carbide (SIC); the correction coefficients for the life of SIC are calculated to be 0.23, for C, to be 0.14, and for stainless steel (Ss), to be 0.31, and the corrected equations can more accurately predict the corresponding material. The corrected equation can more accurately predict the service life of the corresponding material. [ABSTRACT FROM AUTHOR]