In January 2008, the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft became the first probe to fly past the planet Mercury in 33 years. The encounter revealed that Mercury is a dynamic system; its liquid iron-rich outer core is coupled through a dominantly dipolar magnetic field to the surface, exosphere, and magnetosphere, all of which interact with the solar wind. MESSENGER images confirm that lobate scarps are the dominant tectonic landform and record global contraction associated with cooling of the planet. The history of contraction can be related to the history of volcanism and cratering, and the total contractional strain is at least one-third greater than inferred from Mariner 10 images. On the basis of measurements of thermal neutrons made during the flyby, the average abundance of iron in Mercury's surface material is less than 6% by weight.
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Anaerobic fermentation of straw with sulfate addition: A suitable approach for straw utilization in mercury-contaminated areas.
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Key Laboratory of Karst Georesources and Environment (Guizhou University), Ministry of Education, Guiyang, 550025, China.
Returning raw straw to the soil can significantly elevate soil methylmercury (MeHg) and crop mercury (Hg) levels, underscoring the need to investigate safer approaches to straw utilization in mercury-contaminated regions. In this study, rice straw underwent anaerobic fermentation with the addition of sulfate, and the resulting fermentation products were utilized in a pot experiment involving water spinach to assess the impact of anaerobically fermented straw return on soil Hg methylation and its bioaccumulation. Findings revealed that the addition of sulfate during straw fermentation markedly increased the fermentation degree of the products, and sulfate was converted into organic sulfur-containing ligands that can functionalize the fermentation residuals.
View Article and Find Full Text PDFRegulation of straw-derived DOM and clay mineral complexation on mercury accumulation in vegetables.
Environ Res
November 2024
Key Laboratory of Karst Georesources and Environment (Guizhou University), Ministry of Education, Guiyang, 550025, China; College of Resources and Environmental Engineering, Guizhou University, Guiyang, 550025, China.
Article Synopsis
- The study investigates how dissolved organic matter (DOM) from straw affects mercury (Hg) dynamics in soil and plants, particularly focusing on its impact on methylmercury (MeHg) accumulation.
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J Hazard Mater
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Key Laboratory of Karst Georesources and Environment (Guizhou University), Ministry of Education, College of Resources and Environmental Engineering, Guizhou University, Guiyang 550025, China.
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- Soil dissolved organic matter (SDOM) affects how divalent mercury (Hg(II)) behaves and its photoreduction in paddy fields, but the impact of straw returning and soil tillage on SDOM composition is not well understood.
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Importance of Ultraviolet-C (UV-C) Emitter Configuration for Clostridioides difficile Attenuation.
Cureus
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Anesthesiology and Perioperative Medicine, Mayo Clinic, Rochester, USA.
Background: The impact of ultraviolet-C (UV-C) emitter configuration on pathogen attenuation has not been assessed. We hypothesized that emitter configuration would impact UV-C efficacy for () attenuation.
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