摘要：
This study aimed to evaluate the biological effects of gamma irradiation on zebrafish embryos. Different doses of gamma rays (0.01, 0.05, 0.1, 0.5 and 1 Gy) were used to irradiate zebrafish embryos at three developmental stages (stage 1, 6 h post-fertilization (hpf); stage 2, 12 hpf; stage three, 24 hpf), respectively. The survival, malformation and hatching rates of the zebrafish embryos were measured at the morphological endpoint of 96 hpf. The activities of superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR), glutathione peroxidase (GPx) and glutathione S-transferase (GST) were assayed. Morphology analysis showed that gamma irradiation inhibited hatching and induced developmental toxicity in a dose-dependent manner. Interestingly, after irradiation the malformation rate changed not only in a dose-dependent manner but also in a developmental stage-dependent manner, indicating that the zebrafish embryos at stage 1 were more sensitive to gamma rays than those at other stages. Biochemical analysis showed that gamma irradiation modulated the activities of antioxidant enzymes in a dose-dependent manner. A linear relationship was found between GPx activity and irradiation dose in 0.1–1 Gy group, and GPx was a suitable biomarker for gamma irradiation in the dose range from 0.1 to 1 Gy. Furthermore, the activities of SOD, CAT, GR and GPx of the zebrafish embryos at stage 3 were found to be much higher than those at other stages, indicating that the zebrafish embryos at stage 3 had a greater ability to protect against gamma rays than those at other stages, and thus the activities of antioxidant enzymes changed in a developmental stage-dependent manner.
作者机构：
南华大学核资源工程学院,湖南衡阳421001;南华大学铀矿冶生物技术国防重点学科实验室,湖南衡阳421001;[杜康; 李广悦; 刁宁宁; 王永东] School of Nuclear Resources Engineering, University of South China, Hengyang, Hunan 421001, China, Key Discipline Laboratory for National Defense of Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, Hunan 421001, China
通讯机构：
[Li, G.-Y.] S;School of Nuclear Resources Engineering, University of South China, Hengyang, Hunan, China
作者机构：
[董发勤; 刘明学; 聂小琴] Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang, China;[张东] Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, China;[刘宁; 聂小琴] Key Laboratory of Radiation Physics and Technology, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, China;[丁德馨; 李广悦; 聂小琴] Fundamental Science on Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
通讯机构：
Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang, China
摘要：
To verifying the feasibility of uranium recovery with fungal metabolic products in large-scale applications, column leaching and ion exchange of uranium was carried out. The uranium recovery reached 81.76 % in 14 days. The ion exchange curve for the leach solution obtained with the metabolic products of Aspergillus niger was in the shape of a wave. The elution curve was similar to that of leaching with H2SO4. The results indicate that leaching with the metabolic products of A. niger is a promising and environmentally friendly method for exploitation of low grade uranium ores in large-scale applications.
作者机构：
[刘明学; 聂小琴; 董发勤] Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest of Science and Technology, Mianyang, China;[张东] Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, China;[Liu, Ning] Key Laboratory of Radiation Physics and Technology, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, China;[丁德馨; 刘宁] Fundamental Science on Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
通讯机构：
Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest of Science and Technology, Mianyang, China
作者机构：
[董发勤; 刘明学; 聂小琴] Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang, China;[张东] Institute of Nuclear Physics and Chemistry, China Academy of Engineering Physics, Mianyang, China;[刘宁] Key Laboratory of Radiation Physics and Technology, Institute of Nuclear Science and Technology, Sichuan University, Chengdu, China;[丁德馨; 李广悦] Fundamental Science on Biotechnology in Uranium Mining and Hydrometallurgy Laboratory, University of South China, Hengyang, China
通讯机构：
Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory, Southwest University of Science and Technology, Mianyang, China
通讯机构：
[Ding, De-xin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, 28 West Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
关键词：
In situ leaching;Groundwater;Bioreduction;U(VI);Anaerobic zone
摘要：
To determine whether the U(VI) in groundwater under anoxic conditions at a decommissioned in situ leaching (ISL) uranium mine could be bioreduced, groundwater samples containing suspended sediments were taken from the mine, experimental setup was fabricated, and the jar containing the groundwater in the setup was amended with ethanol and incubated under anoxic conditions. The variations of pH, chemical oxygen demand, nitrate, sulfate, U(VI), and dissolved oxygen (DO) concentrations were monitored during the incubation. U(VI) concentration dropped to 0.043 mg/L when the stimulated microorganisms were active, and it then increased to 0.835 mg/L within 10 days after the metabolism of the stimulated microorganisms was inhibited. The DO variation was observed in the amended jar during the incubation, and the metabolism of the stimulated microorganisms was found to affect the DO concentration. Firmicutes were found to be dominant in the sediments in the amended jar through the 16S rRNA pyrosequencing. The results indicate that it is possible to bioreduce U(VI) in the groundwater under anoxic conditions at the decommissioned ISL uranium mine by adding carbon source into it without removing the oxygen from it.
作者机构：
[李广悦; 刁宁宁; 王永东; 杜康; 张振远] Key Discipline Laboratory for National Defense of Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;Hunan;421001, China;School of Nuclear Resources Engineering, University of South China, Hengyang;[李广悦; 刁宁宁; 王永东; 杜康; 张振远] Hunan
期刊：
Journal of Radioanalytical and Nuclear Chemistry,2014年299(3):1903-1909 ISSN：0236-5731
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Li, Guangyue; Hu, Nan; Xin, Xin; Fu, Pingkun] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Li, Le] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
通讯机构：
[Ding, Dexin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词：
Sodium feldspar;U(VI) ion adsorption;Low concentration aqueous solution;Kinetic;Water treatment
摘要：
The raw sodium feldspar (RSF) is activated with the concentrated sulfuric acid solution and the acid activated sodium feldspar (AASF) is obtained. The results obtained from the mercury intrusion method show that the acidification can increase the porosity and the specific surface area. The effects of the initial pH, contact time and ambient temperature on the adsorption of U(VI) ions are investigated in a batch process. The adsorption efficiency amounts to the highest at pH 6 and the adsorption equilibrium is reached in 600 min. The pseudo-second-order model is found to be more suitable for the adsorption process than the pseudo-first-order model and intra-particle model, indicating that the chemical adsorption is the predominant step for the adsorption process. Langmuir model is found to describe the adsorption process better than Freundlich model. This proves that the main form of U(VI) ions attached to RSF and AASF is the monolayer coverage. The thermodynamic parameters prove that the adsorption process is a spontaneous endothermic one. It was also found that acid activated treatment can help increase the adsorption rate and capacity. The results show that RSF and AASF can be used as a novel low cost adsorbent for removal of U(VI) ions from the low concentration aqueous solution.
作者机构：
[李广悦; 扶海鹰; 叶勇军; 丁德馨; 宋键斌; 胡南; 王永东] Key Discipline Lab for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China
通讯机构：
Key Discipline Lab for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, China
关键词：
铀矿;柱浸;堆浸;数学模型;浸出率
摘要：
针对铀矿堆浸生产中矿堆不同高度上的铀金属浸出存在的延迟现象,采用理论分析和室内柱浸试验研究铀矿浸出试验柱不同高度上铀金属浸出的规律。理论分析将铀矿浸出试验柱沿柱高划分为若干个高度足够小且相等的单元体,使其中单个铀矿石颗粒的浸出符合收缩未反应核扩散控制系统模型,且任意1个单元体内所有铀矿石颗粒反应均匀,不存在延迟现象,进而以1个单元体为目标,根据溶浸剂质量守恒原理,并考虑初始溶浸剂浓度的变化,建立铀矿浸出试验柱不同高度上铀金属浸出的数学模型。采用颗粒半径为2.5 mm 的铀矿石进行串联柱浸试验。然后,采用数学模型对柱浸试验结果进行计算,并将模型计算结果与柱浸试验结果进行比较。研究结果表明:试验柱不同高度上铀金属浸出率存在较大差别,且模型计算值与柱浸试验值具有相同的变化趋势,表明该数学模型能较好地反映铀矿浸出试验柱不同高度上铀金属浸出的延迟规律,可为预测铀矿堆浸不同高度上的浸出率提供重要参考。
通讯机构：
Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
作者机构：
[李广悦; 王永东; 扶海鹰; 宋键斌; 胡南; 丁德馨; 叶勇军] Key Discipline Lab for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China
通讯机构：
Key Discipline Lab for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, China
