Publications by authors named "Zhengcheng Song"

Monomethylmercury (MMHg) is a potent neurotoxin that poses a threat to human health. MMHg cycles in all spheres of the Earth but the sources and fate of atmospheric MMHg are unclear. Here, we develop a global model for atmospheric MMHg, which integrates the presently available data and indicates the limitations of the current study.

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The redox chemistry of mercury (Hg) in the atmosphere exerts a significant influence on its global cycle. However, our understanding of this important process remains shrouded in uncertainty. In this study, we utilize three-dimensional atmospheric Hg isotope modeling to evaluate the isotopic composition of particle-bound mercury [Hg(P)] in the global atmosphere.

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Mercury (Hg), a potent neurotoxin posing risks to human health, is cycled through vegetation uptake, which is susceptible to climate change impacts. However, the extent and pattern of these impacts are largely unknown, obstructing predictions of Hg's fate in terrestrial ecosystems. Here, we evaluate the effects of climate change on vegetation elemental Hg [Hg(0)] uptake using a state-of-the-art global terrestrial Hg model (CLM5-Hg) that incorporates plant physiology.

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Sea ice (including overlying snow) is a dynamic interface between the atmosphere and the ocean, influencing the mercury (Hg) cycling in polar oceans. However, a large-scale and process-based model for the Hg cycle in the sea ice environment is lacking, hampering our understanding of regional Hg budget and critical processes. Here, we develop a comprehensive model for the Hg cycle at the ocean-sea ice-atmosphere interface with constraints from observational polar cryospheric data.

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Riverine processes are crucial for the biogeochemical cycle of mercury (Hg). The Yangtze River, the largest river in East Asia, discharges a substantial amount of Hg into the East China Sea. However, the influencing factors of the Hg budget and its recent trends remain unclear.

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Mercury (Hg) is a strong neurotoxin with substantial dangers to human health. Hg undergoes active global cycles, and the emission sources there of can also be geographically relocated through economic trade. Through investigation of a longer chain of the global biogeochemical Hg cycle from economic production to human health, international cooperation on Hg control strategies in Minamata Convention can be facilitated.

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The vegetation uptake of atmospheric elemental mercury [Hg(0)] and its subsequent littering are critical processes of the terrestrial Hg cycles. There is a large uncertainty in the estimated global fluxes of these processes due to the knowledge gap in the underlying mechanisms and their relationship with environmental factors. Here, we develop a new global model based on the Community Land Model Version 5 (CLM5-Hg) as an independent component of the Community Earth System Model 2 (CESM2).

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Mercury (Hg) stable isotope analysis has become a powerful tool to identify Hg sources and to understand its biogeochemical processes. However, it is challenging to link the observed Hg isotope fractionation to its global cycling. Here, we integrate source Hg isotope signatures and process-based Hg isotope fractionation into a three-dimensional isotope model based on the GEOS-Chem model platform.

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Non-ferrous metal smelting is a significant source of anthropogenic heavy metal emission and has led to severe environmental pollution that ultimately threatens the health of local residents. In this study, we determined concentrations of copper (Cu), zinc (Zn), cadmium (Cd) and lead (Pb), as well as Pb isotopic compositions in rice, vegetables and human hair in areas surrounding the Zhuzhou Pb/Zn smelter in Hunan, China and we assessed the health risks associated with rice and vegetable consumption for local residents. Results showed that rice and vegetable samples were significantly contaminated by Cd and Pb.

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Mercury is a potent neurotoxin that poses health risks to the global population. Anthropogenic mercury emissions to the atmosphere are projected to decrease in the future due to enhanced policy efforts such as the Minamata Convention, a legally-binding international treaty entered into force in 2017. Here, we report the development of a comprehensive climate-atmosphere-land-ocean-ecosystem and exposure-risk model framework for mercury and its application to project the health effects of future atmospheric emissions.

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Chlor-alkali plants (CAPs) are major consumers of mercury (Hg) and may be a source of severe Hg pollution to the environment. In this paper, the total mercury (THg) concentrations and the speciation and mobility of Hg were measured in salt slurry and soils collected from an abandoned CAP in Yunnan Province, China. THg concentrations in the salt slurry samples varied widely and ranged from 0.

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The effects of aluminum on the mechanical properties and corrosion behavior in artificial seawater of Cu-Ni-Fe-Mn alloys were investigated. Cu-7Ni-Al-1Fe-1Mn samples, consisting of 0, 1, 3, 5, and 7 wt % aluminum along with the same contents of other alloying elements (Ni, Fe, and Mn), were prepared. The microstructure of Cu-7Ni-Al-1Fe-1Mn alloy was analyzed by Transmission Electron Microscopy (TEM), and its corrosion property was tested by an electrochemical system.

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