• Shi Zeming

Articles written in Journal of Earth System Science

• Mechanism of post-seismic floods after the Wenchuan earthquake in the upper Minjiang River, China

By analyzing the multi-year runoff and rainfall data at 15 hydrological stations from 1980 to 2007, as well as monthly runoff data from 1964 to 1984 at the Zipingpu hydrologic station, the relationship between precipitation and runoff has been established and the trend was explored. Based on the catastrophic floods of August 13 and August 18, 2010, characteristics and control factors on the post-seismic floods are summarized. Firstly, the Wenchuan earthquake and rupture zone provides the background for post-seismic floods to develop in the upper Minjiang River, which follows a post-seismic disaster-chain pattern: earthquake collapse to landslide debris flows to floods. Secondly, heavy rainfall controlled by the orographically-enhanced precipitation after the Wenchuan earthquake is the trigger factor for the development of devastating post-seismic floods. Thirdly, the post-seismic floods contain high sediment discharge, cause abrupt and severe damages, and have a large of volume and higher frequency.

• Uranium sorption onto mullite: Characteristics of isotherms, kinetics and thermodynamics

The sorption of uranium onto mullite influenced by pH, initial adsorbate concentration, sorption dose and reaction duration was probed utilising batch techniques. X-ray powder diffraction was used to characterise mullite. Sorption isotherms, sorption kinetics and thermodynamic characteristics were also investigated. The Freundlich isotherm model could best depict experimental data, suggesting that the sorption mechanism of uranium onto mullite may be multi-layer adsorption. The E value obtained from the Dubinin–Radushkevich model implied that uranium sorption onto mullite is a chemical process. The pseudo-second-order model successfully depicted uranium sorption onto mullite, indicating that the sorption rate is mainly controlled by chemical sorption. The thermodynamic parameters computed showed that entropy and enthalpy under the trial conditions were positive and that values of ${\Delta}G$$^{\Theta}$ were negative. Thermodynamics illustrated that the sorption process was endothermic and spontaneous. The results achieved in this study are intended to further a deeper comprehension of uranium migration in silicate minerals.

• # Journal of Earth System Science

Current Issue
Volume 128 | Issue 8
December 2019

• # Editorial Note on Continuous Article Publication

Posted on July 25, 2019