Wanshan mercury mine is the largest cinnabar deposit in Guizhou, China. Few effective methods had been achieved to remedy
Hg heavily contaminated field soils. In this paper, a modified EK method with approaching cathodes (AC-EK) and an I−/I2 lixiviant was described to remedy mercury-contaminated field soils near Wanshan mercury mine. Paddy Soil I and Paddy Soil
II were sampled and contained 576.73 ± 45.50 and 491.35 ± 4.73 mg/kg Hg, respectively. Although they contained 6.9 and 9.4%
organic matter respectively, more than 92 and 89% Hg were removed by AC-EK within 5 days. Removal ratio increased by 0.21
and 0.68 times using EK process with ACs over that with one single cathode (SC-EK). AC-EK method saved nearly 26.4–28.1% electric
power as compared to SC-EK method. As an I−/I2 lixiviant solution was used to solubilize HgS(HgO) during EK process, the bonding of Hg to organic functional S groups should
be less important than the binding to inner sites of organic matter in soil. The relationship between EK remediation effect
and soil organic matter content was fitted to a linear model. It turned out that when soil OM increased by 1.0%, EK removal
ratio (%) of Hg would decrease by 2.63%. 相似文献
The Hongqiling Cu–Ni sulfide deposit in central Jilin Province is located in the eastern part of the Central Asian Orogenic Belt. Rhenium and osmium isotopes in sulfide minerals from the deposit are used to determine the timing of mineralization and the source of osmium, and ore metals. Sulfide ore samples have osmium and rhenium concentrations of 0.28–1.07 ppb and 2.39–13.17 ppb, respectively. Ten analyses yield an isochron age of 223 ± 9 Ma, indicating that the Cu–Ni sulfide deposit in the area formed in the Triassic. The initial 187Os/188Os ratio is around 0.295 ± 0.019 (MSWD = 1.14) and the δ34S values of sulfide ores vary from ?1.50 to +3.00‰. These data indicate that the mineralizing materials were derived mainly from a mantle with some quantities of crustal components introduced into the rock‐forming and ore‐forming systems during mineralization and magmatic emplacement. 相似文献
Prediction on landslide displacement plays an important role in landslide early warning. Many models have been proposed for this purpose. However, the accuracy of the prediction results by these models often varies under different conditions. Rational evaluation and comprehensive consideration of these results still remain a scientific challenge. A new comprehensive combination model is proposed to predict the landslides displacement. The elementary displacement prediction is made by the support vector machine model, the exponential smoothing model, and the gray model (GM)(1,1). The results of the models are comprehensively evaluated by combining the results and introducing the accuracy matrix. The optimal weight in the evaluation work is obtained. A rational prediction result can be attained based on the so-called combination model. The proposed method has been tested by the application of Qinglong landslides in Guizhou Province, China. The comparison between the prediction results and in situ measurement shows that the prediction precision of the proposed model is satisfactory. The root-mean-square error (RMSE) of the combination model can be reduced to 1.4316 (monitoring site JCK2), 1.2623 (monitoring site JCK4), 2.3758 (monitoring site JCK6), 2.2704 (monitoring site JCK8), 1.4247 (monitoring site JCK11), and 0.9449 (monitoring site JCK12), which is much lower than the RMSE of the individual models.