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This study aims at counteracting the problem of rejuvenated asphalt with poor performance and weak secondary anti-aging ability by improving the existing biomass rejuvenator. In this study, a carbon nanomaterial, graphene oxide (GO) with excellent anti-aging performance, was introduced to the wood tar-based rejuvenator (WR) to prepare a composite rejuvenator. Based on laboratory tests, the effects of the GO–wood tar-based composite rejuvenator (GWCR) on the performance of aged asphalt and on the secondary aging performance were investigated, and its rejuvenation mechanism was analyzed. The results indicate that the GWCR can increase the penetration, ductility, and creep rate (m) of aged asphalt while decreasing its softening point, rutting factor (G*/sinδ), and stiffness modulus (S). This indicates that the high-temperature resistance to the permanent deformation ability of aged asphalt degrades, while the low-temperature performance improves, and all values are slightly greater than those of the 70# original base asphalt. After PAV aging, the S value of the GO–wood tar-based composite rejuvenated asphalt (GWCRA) increased by 83.71%, while the m value decreased by 49.45%. The secondary aging resistance of the GWCRA is better than that of 70# original base asphalt, RA-75 rejuvenated asphalt, and wood tar-based rejuvenated asphalt. When adding the GWCR into aged asphalt, the content of saturates and aromatics in the asphalt increases by 1.08% and 11.1%, respectively. In contrast, the content of asphaltenes and resins decreases by 6.288% and 5.9%, respectively. As a result, the colloidal structure of the aged asphalt transfers from a gel to a sol–gel state. The surface roughness of the GWCRA increases by the synergistic effect of GO and wood tar, making its adhesion better than that of the 70# original base asphalt. Adding GO can improve the performance of wood tar rejuvenated asphalt (WRA) with high-temperature deformation resistance and resistance to secondary aging, and effectively make up for the defects in the performance of WRA rejuvenated asphalt, so as to extend the service life of asphalt pavements, thus increasing the value of wood tar engineering applications, which is of great practical significance. [ABSTRACT FROM AUTHOR]

The middle reaches of the Lancang‐Mekong River Basin (M‐LMRB) experienced a record‐breaking drought event in 2019, resulting in significant economic losses of approximately 650 million dollars and affecting a population of 17 million. However, the anomalous circulation and transportation processes of water vapor, which may have played a crucial role in inducing the extreme drought, have not been fully studied. In this study, we analyze the water vapor circulation during the 2019 drought event using the land‐atmosphere water balance and a backward trajectory model for moisture tracking. Our results indicate that the precipitation in the M‐LMRB from May to October 2019 was only 71.9% of the long‐term climatological mean (1959–2021). The low precipitation during this drought event can be attributed to less‐than‐normal external water vapor supply. Specifically, the backward trajectory model reveals a decrease in the amount of water vapor transported from the Indian Ocean, the Bay of Bengal, and the Pacific Ocean, which are the main moisture sources for precipitation in the region. Comparing the atmospheric circulation patterns in 2019 with the climatology, we identify anomalous anticyclone conditions in the Bay of Bengal, anomalous westerlies in the Northeast Indian Ocean, and an anomalous cyclone in the Western Pacific Ocean, collectively facilitating a stronger export of water vapor from the region. Therefore, the dynamic processes played a more significant role than thermodynamic processes in contributing to the 2019 extreme drought event. Plain Language Summary: In 2019, a record‐breaking drought hit the M‐LMRB, leading to significant economic losses and affecting a large population. This study explores the water vapor circulation during this drought using land‐atmosphere water balance and a backward trajectory model. Findings show that precipitation from May to October 2019 was only seventy percent of the average from 1959 to 2021. The drought's severity was mainly due to a lack of water vapor from key sources: the Indian Ocean, the Bay of Bengal, and the Pacific Ocean. Anomalous weather patterns—an anticyclone in the Bay of Bengal, unusual westerlies in the Northeast Indian Ocean, and a cyclone in the Western Pacific—led to a significant reduction in water vapor reaching the region. This indicates that dynamic atmospheric processes played a larger role in causing the extreme drought than thermodynamic ones. These insights help improve understanding and prediction of droughts in Southeast Asia, particularly under changing climate conditions. Key Points: Reduced external water vapor transport primarily leads to negative precipitation anomaliesThere has been a reduction in water vapor originating from the Indian Ocean, Bay of Bengal, and Pacific OceanThe reduction in water vapor transport is primarily influenced by dynamic factors rather than thermodynamic ones [ABSTRACT FROM AUTHOR]

This study utilized molecular dynamics simulation to investigate the adhesion process between wood tar-rejuvenated asphalt and acid/alkaline aggregate. Initially, various indicators including the contact area, cohesion coefficient, and interaction energy were employed to assess the adhesion effect under dry conditions. This revealed the action mechanism of the wood tar-rejuvenator in enhancing the adhesion performance between aged asphalt and aggregate. Subsequently, an asphalt–water–aggregate interface model was developed to simulate the water damage process of the asphalt mixture. This aimed to unveil the damage mechanism of water intrusion on the adhesion performance of the asphalt–aggregate interface and evaluate the water damage resistance of wood tar-rejuvenated asphalt through adhesion energy, stripping work, and the energy ratio. The findings indicate that wood tar-rejuvenated asphalt exhibits favorable adhesion properties with both acid and alkaline aggregates. The addition of wood tar-rejuvenated asphalt increased the interaction energy between aged asphalt and acid and alkali aggregates by 67.75 kJ/mol and 97.3 kJ/mol, respectively. The addition of a wood tar rejuvenator enhances the interaction energy between aged asphalt and aggregate, thereby increasing mutual attraction and enlarging the contact area. The adhesion between asphalt and aggregates hinges on the interaction between asphaltene and aggregates, and the wood tar rejuvenator reduces the diffusion ability of asphaltene in the attractive state of the aggregate, resulting in stable aggregation. Moisture intrusion increased the aggregation distance between asphaltene and aggregate by 14.1% and decreased the degree of aggregation by 24.0%, thereby reducing the interaction energy. The extent of damage caused by water intrusion is linked to the aggregation distance, with greater distances leading to deeper damage. Under wet conditions, the interaction energy of wood tar-rejuvenated asphalt increased by 78.2% in the acidic aggregate system and 98.1% in the basic aggregate system compared with aged asphalt. Meanwhile, wood tar-based rejuvenated asphalt improves the adhesion between aged asphalt and aggregate and reduces the stripping function of asphalt affected by water replacement, which results in the ER value of wood tar-rejuvenated asphalt being higher than that of the original asphalt by 0.12 and 0.22 in the acidic and alkaline environments, respectively, thus showing excellent resistance to water damage. This study provides new criteria for the selection of rejuvenators for waste asphalt, which will help in the future selection of superior rejuvenators for aged asphalt and reduce the possibility of choosing the wrong rejuvenator. [ABSTRACT FROM AUTHOR]

Electric vehicle battery internal parameters vary with load and working conditions, so it is necessary to establish an accurate power battery model. Based on the equivalent circuit model of lithium battery and considering the influence of operating temperature and state of charge(SOC) on component parameters, this paper relied on charge and discharge method, combined hybrid pulse power characteristic(HPPC) tests and least squares method to realize each component parameter identification. The power battery model and the charge and discharge model were constructed by Simulink platform. The above models realized the accurate estimation of SOC by the ampere-hours measurement method and considering temperature influence. The results show that the lithium battery parameters identification model can accurately simulate operating characteristics of the power battery under various load conditions. The design can be applied to testing and developing power batteries.