摘要：
Dynamic shear modulus and damping ratio are two main parameters for describing the dynamic performance of aeolian soils. This paper presents the influence of the confining pressure, the consolidation ratio and the vibration frequency on the dynamic shear modulus and the damping ratio of aeolian soils with a series of dynamic triaxial tests. Experimental results show that the dynamic shear modulus of aeolian soils increases with the confining pressure and the consolidation ratio, while the damping ratio decreasing with them; both of the dynamic shear modulus and the consolidation ratio increases with the vibration frequency, but the influence is less than that of the confining pressure and the consolidation ratio.
作者机构：
[许满贵; 李树刚] School of Energy Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China;[赵勇] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China
通讯机构：
School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
摘要：
In this study, a one-dimensional steady-state mathematical model of radon transport in fragmented uranium ore was established according to Fick's law and radon transfer theory in an air-water interface. The model was utilized to obtain an analytical solution for radon concentration in the air-water, two-phase system under steady state conditions, as well as a corresponding radon exhalation rate calculation formula. We also designed a one-dimensional experimental apparatus for simulating radon diffusion migration in the uranium ore with various water levels to verify the mathematical model. The predicted results were in close agreement with the measured results, suggesting that the proposed model can be readily used to determine radon concentrations and exhalation rates in fragmented uranium ore with varying water levels.
作者机构：
[石竞羽] School of Environmental and Safety Engineering, University of South China, Hengyang, 421001, China;The Graduate School of University of South China, Hengyang, 421001, China;[戴剑勇] School of Environmental and Safety Engineering, University of South China, Hengyang, 421001, China, The Graduate School of University of South China, Hengyang, 421001, China
通讯机构：
[Shi, J.] S;School of Environmental and Safety Engineering, University of South China, Hengyang, China
作者机构：
[Jing Zhao; Taiping Xie; Longjun Xu] State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China;[Chao Xie] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China
通讯机构：
[Jing Zhao] S;State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, China
关键词：
Chemical bath deposition method;Low-grade rhodochrosite ore;Mn3O4
期刊：
Electronic Journal of Geotechnical Engineering,2015年20(25):12113-12120 ISSN：1089-3032
通讯作者：
Feng, Shengyang(fengshengyang13@163.com)
作者机构：
[Feng, Shengyang; Wang, Shuyun; Li, Xiangyang; Chen, Zhi] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
通讯机构：
School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
摘要：
The electron cyclotron wave (ECW) current drive (CD) for the HL-2A tokamak is investigated numerically with a new ray-tracing and Fokker-Planck code. The code is benchmarked with other well-tested linear and quasilinear codes and is then used to study the electron cyclotron current drive on the HL-2A tokamak. The wave propagation, power deposition, and driven-current profiles are presented. The effect of electron trapping is also assessed. It is found that quasilinear effects are negligible at the present ECW power levels and that when both waves are injected at an angle of 20° on the plasma equatorial plane, the CD efficiency for the HL-2A saturates at ∼0.029 × 1020 A/W/m2 and ∼0.020 × 1020 A/W/m2 for the 0.5 MW/68 GHz first harmonic ordinary (O1) and 1 MW/140 GHz second harmonic extraordinary (X2) modes, respectively. The effects of the plasma density, temperature, and wave-launching position on the driven current are also investigated analytically and numerically.
摘要：
Total suspended particle (TSP) and fine particulate matter (PM2.5) samples were collected continuously using an atmospheric particulate matter sampler at sampling points in a tailings reservoir in the south from October 28 to November 3, 2013. The mass concentrations of particulate matter in the air, the contents, and morphological analysis of heavy metal elements (Pb, Cd, U, Cu) were also studied. The results indicate that the air particulate matter concentrations exceed the mass concentration limits of national Grade II ambient air quality standard (GB3095-2012); The heavy metals content in air particulate matter from high to low order is: Pb > Cu > U > Cd and heavy metals are easier to be concentrated on fine particulate matter (PM2.5); heavy metal elements (Pb, Cd, Cu) exist mainly in the exchangeable morphology, especially the element Cd.
期刊：
Mineral Processing and Extractive Metallurgy: Transactions of the Institute of Mining and Metallurgy,2015年124(3):132-136 ISSN：2572-6641
通讯作者：
Xu, L.
作者机构：
[J. Zhao; L. Xu; T. Xie] State Key Laboratory of Coal Mine Disaster Dynamics and ControlChongqing University, Chongqing400044, China;[C. Xie] School of Environmental Protection and Safety EngineeringUniversity of South China, Hengyang421001, China
通讯机构：
[L. Xu] S;State Key Laboratory of Coal Mine Disaster Dynamics and ControlChongqing University, Chongqing400044, China
作者机构：
[Yongjun Y.; Xiangyang L.; Shuyun W.] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China;[Longjun X.] State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China;[Chao X.] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China, State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China
通讯机构：
[Xu Longjun] S;State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, China
摘要：
Mn-Zn ferrite powders were produced from low-grade manganese ore (LMO) via the chemical coprecipitation method combined with the ceramic method, after the LMO was leached in sulfuric acid and the obtained solution was purified. The effect of the pH on the magnetic properties of Mn-Zn ferrite was investigated by the varying pH of the co-precipitation system. The crystal structure and phases of the samples were characterized by X-ray diffraction and infrared spectrum, respectively. The magnetic measurements were carried out on a vibrating sample magnetometer. The optimal sample was obtained with a saturation magnetization of 55.02 emu/g, a coercivity of 8.20 G and a remanent magnetization of 1.71 emu/g when pH is 7.5.
作者机构：
[叶勇军; 赵娅利; 谢东; 李向阳; 钟永明; 王立恒] School of Environment Protection and Safety Engineering, University of South China, Hengyang, China;[叶勇军; 丁德馨] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
通讯机构：
Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
