Microbial fuel cells coupled with the bioleaching technique that enhances the recovery of Cu from the secondary mine tailings in the bio-electrochemical system
作者：
Huang, Tao* ;Liu, Longfei* ;Zhang, Shuwen
期刊：
ENVIRONMENTAL PROGRESS & SUSTAINABLE ENERGY ,2019年38(5):13181- ISSN：1944-7442
通讯作者：
Huang, Tao;Liu, Longfei
作者机构：
[Liu, Longfei; Huang, Tao; Liu, LF] Changshu Inst Technol, Sch Chem & Mat Engn, Changshu 215500, Jiangsu, Peoples R China.;[Zhang, Shuwen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构：
[Huang, T; Liu, LF] C;Changshu Inst Technol, Sch Chem & Mat Engn, Changshu 215500, Jiangsu, Peoples R China.
关键词：
bioleaching;microbial fuel cell;Cu recovery;bio-electrochemical system;secondary mine tailing
摘要：
Improper management of dumped tailings not only causes a potential waste of resources but also poses a direct threat to the lives of local residents. A dual-chamber microbial fuel cell (MFC) combining with the bioleaching technique was used in the study to extract Cu from the secondary mine tailings at a fed-batch scale. A mixed culture of acidophilic bacteria was enriched and isolated from the acidic drainage in a copper mine. The effects of the pulp densities and initial pH on both the bio-electronic performances and the recoveries of Cu on bio-electrochemical platform were comparatively investigated. An appropriate increase in the pulp densities and a suitable decrease in the initial pH facilitated increases in power generations and enhanced the recoveries of Cu from the tailing samples. The maximum power density of 30.54 mW/m2 was achieved in the coupling system with the coulomb efficiency of 4.52%, and the internal resistance of 166.58 Ω being synchronously obtained. Correspondingly, the highest recovery efficiency of Cu of 78.72% was got in the two-dimensional tests under conditions including the pulp density (w/v) of 20% and the initial pH of 1.8. The electrochemical reduction and the chemical precipitation in MFCs were confirmed as two of main mechanisms in obviously influencing the recovery of Cu. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019. © 2019 American Institute of Chemical Engineers
语种：
英文
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Aspergillus niger changes the chemical form of uranium to decrease its biotoxicity, restricts its movement in plant and increase the growth of Syngonium podophyllum
作者：
Zou Chao;Sha Yin-hua;Ding De-xin;Li Guang-yue;Cui Yue-ting;...
期刊：
Chemosphere ,2019年224(Jun.):316-323 ISSN：0045-6535
通讯作者：
Wang Yong-dong
作者机构：
[Li Feng; Zou Chao; Dai Zhong-ran; Ding De-xin; Li Guang-yue; Hu Nan; Wang Yong-dong; Cui Yue-ting; Sun Jing; Sha Yin-hua; Zhang Hui] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Heng Yang 421001, Hunan, Peoples R China.
通讯机构：
[Wang Yong-dong] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Heng Yang 421001, Hunan, Peoples R China.
关键词：
Aspergillus niger;Combined remediation system;Phytoremediation;Syngonium podophyllum;Uranium stress
摘要：
Aspergillus niger (A. niger) and Syngonium podophyllum (S. podophyllum) have been used for wastewater treatment, and have exhibited a promising application in recent years. To determine the effects of A. niger on uranium enrichment and uranium stress antagonism of S. podophyllum, the S. podophyllum-A. niger combined system was established, and hydroponic remediation experiments were carried out with uranium-containing wastewater. The results revealed that the bioaugmentation of A. niger could increase the biomass of S. podophyllum by 5–7%, reverse the process of U(VI) reduction induced by S. podophyllum, and increase the bioconcentration factor (BCF) and translocation factor (TF) of S. podophyllum to uranium by 35–41 and 0.01–0.06, respectively, thereby improving the reduction of uranium in wastewater. Moreover, A. niger could promote the cell wall immobilization and the subcellular compartmentalization of uranium in the root of S. podophyllum, reduce the phytotoxicity of uranium entering root cells, and inhibit the calcium efflux from root cells, thereby withdrawing the stress of uranium on S. podophyllum. © 2019
语种：
英文
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基于图像分析的堆浸铀矿石颗粒参数辨识
作者：
宁志刚;郝光鹏;程雄;沈文斌;丁德馨
期刊：
北京理工大学学报 ,2018年38(3):300-304 and 312 ISSN：1001-0645
作者机构：
[宁志刚; 郝光鹏; 程雄; 沈文斌] College of Electrical Engineering, University of South China, Hengyang;Hunan;421001, China;[丁德馨] School of Nuclear Resource Engineering, University of South China, Hengyang;[宁志刚; 郝光鹏; 程雄; 沈文斌; 丁德馨] Hunan
关键词：
颗粒参数;引导滤波;PCNN模型;凹点匹配;形状特征
摘要：
采用数字图像处理技术对铀矿石颗粒参数进行测量,并确定铀矿石块度分布.首次将图像引导滤波器应用于矿石图像滤波,较好地滤除了图像噪声和保持矿石边缘细节信息.采用基于最大类间后验交叉熵准则的PCNN图像分割算法分割矿石图像,减少了矿石粘连现象.为了解决第一次分割后矿石粘连现象,采用基于凹点匹配的数字图像切割算法对粘连的矿石图像进行第二次分割,能有效分离粘连矿石图像.采用基于形状特征的颗粒参数测量法测量颗粒参数,提高了颗粒参数的测量精度,得到了矿石块度的统计分布图.实验数据表明,该方法测量误差较小,能满足实际需求.
语种：
中文
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The effect of laterite density on radon diffusion behavior
作者：
Li, Yongmei;Tan, Wanyu;Tan, Kaixuan* ;Liu, Zehua;Fang, Qi;...
期刊：
Applied Radiation and Isotopes ,2018年132:164-169 ISSN：0969-8043
通讯作者：
Tan, Kaixuan
作者机构：
[Guo, Yueyue; Li, Yongmei; Liu, Zehua; Tan, Wanyu; Tan, Kaixuan; Duan, Xianzhe] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Hunan, Peoples R China.;[Fang, Qi; Lv, Junwen; Liu, Zhenzhong] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Tan, Kaixuan] U;Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Diffusion coefficient;Laterite;Radon;Soil density
摘要：
Radon generated in porous media such as soils and rocks migrates into indoor and outdoor air mainly by diffusion, possessing significant hazards to human health. In order to reduce these hazards of radon, it is of great importance to study the diffusion behavior of radon. In this study, we systematically measured the radon diffusion coefficient of laterite with the density ranging from 0.917 g cm −3 to 2.238 g cm −3 , and studied the effect of laterite density on the radon diffusion. The results show that the radon diffusion coefficient of the laterite generally decreases with the increasing laterite density. In addition, three possible relationships between the radon diffusion coefficient and the laterite density are found out as follows: (1) the linear correlation with a slope of −4.48 × 10 −6 for laterite with density ranging from 0.917 to 1.095 g cm −3 , (2) the exponential correlation for laterite with density from 1.095 to 1.63 g cm −3 , (3) linear correlation with a slope of −3.1 × 10 −7 for laterite with density from 1.63 to 2.238 g cm −3 . The complex relationship between the radon diffusion coefficient and density is caused by the change of porosity and tortuosity of the laterite. Therefore, we suggest that a suitable density should be adopted while using the laterite to effectively cover uranium tailings or economically produce building materials that can curb the radon exhalation. © 2017 Elsevier Ltd
语种：
英文
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氧化石墨烯复合材料吸附铀的研究进展
作者：
刘红娟;谢水波;张希晨;刘迎九;曾涛涛
期刊：
材料工程 ,2018年46(5):11-21 ISSN：1001-4381
通讯作者：
Xie, Shui-Bo(xiesbmr@263.net)
作者机构：
[刘红娟; 谢水波] Institute of Nuclear Science and Technology, University of South China, Hengyang;Hunan;421001, China;Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;[张希晨; 刘迎九; Zeng, Tao-Tao] Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang
通讯机构：
[Xie, S.-B.] I;Institute of Nuclear Science and Technology, University of South China, Hengyang, Hunan, China
关键词：
石墨烯;复合材料;铀;吸附;微观结构
摘要：
氧化石墨烯由于具有超大的比表面积、高强度和化学稳定性好等优点,其在环保领域作为含铀废水吸附材料的应用潜能备受关注。本文综述了近年来石墨烯基复合材料吸附水溶液中铀的研究现状及进展,介绍了石墨烯基复合材料对铀的吸附性能,分析了溶液pH值、温度、离子强度、接触时间和吸附剂用量等因素对吸附效果影响的原理,阐述了通过表面络合模型,光谱分析和理论计算等方法探讨氧化石墨烯复合材料的微观形貌结构与铀吸附效果之间的内在联系,最后研究了氧化石墨烯复合材料吸附铀研究中面临的挑战,对石墨烯材料与轴的相互作用机理及其在环保方面的开发应用进行了展望。
语种：
中文
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Simultaneous determination of the radon diffusion coefficient and the free radon production rate from compact porous emanation media
作者：
Ye, Yong-jun* ;Wu, Wen-hao;Feng, Sheng-yang;Huang, Chun-huang;Li, Shi
期刊：
Building and Environment ,2018年144:66-71 ISSN：0360-1323
通讯作者：
Ye, Yong-jun
作者机构：
[Li, Shi; Ye, Yong-jun; Wu, Wen-hao; Feng, Sheng-yang] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Huang, Chun-huang] Univ South China, Sch Civil Engn, Hengyang 421001, Hunan, Peoples R China.;[Ye, Yong-jun] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ye, Yong-jun] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Compact porous emanation media;Diffusion coefficient;Production rate;Radon
摘要：
The radon diffusion coefficient and the free radon production rate are important parameters for used to describe the migration of radon in porous emanation media. However, the method currently used to determine these two parameters is complicated. Based on a theory of the radon exhalation by diffusion from the inner and outer surfaces of a circular tube, a method to determine these two parameters in compact porous emanation media was proposed, and an experimental measuring device was designed and manufactured. The experimental device was used to simultaneously measure the radon exhalation rate from the inner and outer surfaces of a quarter-circular tubular concrete block filled with fine-grained uranium tailing sand. The measurements were used to calculate the radon diffusion coefficient and the free radon production rate. The result obtained by using this method shows that accuracy was within the accepted range of experimental error. This method has practical value for the simultaneous determination of the radon diffusion coefficient and the free radon production rate from compact porous emanation media. © 2018
语种：
英文
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A Numerical Research on Crack Process of Gypsum Containing Single Flaw with Different Angle and Length in Uniaxial Loading
作者：
Dai Bing;He Guicheng* ;Zhang Zhijun
期刊：
Shock and Vibration ,2018年2018 ISSN：1070-9622
通讯作者：
He Guicheng
作者机构：
[He Guicheng; Zhang Zhijun; Dai Bing] Univ South China, Nucl Resources Engn Coll, Hengyang, Peoples R China.;[He Guicheng; Dai Bing] Tech Univ Bergakad Freiberg, Inst Geotech, Freiberg, Germany.
通讯机构：
[He Guicheng] U;[He Guicheng] T;Univ South China, Nucl Resources Engn Coll, Hengyang, Peoples R China.;Tech Univ Bergakad Freiberg, Inst Geotech, Freiberg, Germany.
摘要：
To investigate the crack behaviour of rock or rock-like material in uniaxial loading, a series of numerical simulations were conducted on gypsum specimens containing a single flaw with different inclination angle (0°-90°) and length (10 mm-30 mm). Based on the numerical simulations results, the effect of flaw length on peak strength, the CI stress, and the CD stress were investigated with different inclination angles. The results show that the peak strength decreased initially and then increased with increasing of the flaw angle. Meanwhile, the peak strength decreased gradually when the length of the preexisting flaw increased. When the inclination angle was 30°, 45°, and 60°, the reduction degree of peak strength increased with increasing of the flaw length. The CI stress and CD stress not only depend on the inclination angle but also depend on flaw length. Four types of crack were observed in numerical simulations. The present research facilitates increased understanding of crack behaviour of rock under different conditions.<br/> ©2018 Dai Bing et al.
语种：
英文
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A novel resonance fluorescence chemosensor based on the formation of heterobinuclear complex with a di-tetradentate macrocyclic ligand and europium (III) for the determination of uranium (VI)
作者：
Wang, Jiao;Xiao, Xilin* ;He, Bo;Jiang, Min;Nie, Changming;...
期刊：
Sensors and Actuators B-Chemical ,2018年262:359-364 ISSN：0925-4005
通讯作者：
Xiao, Xilin;Liao, Lifu
作者机构：
[Xiao, XL; Liao, Lifu; Wang, Jiao; Xiao, Xilin; Jiang, Min; Nie, Changming; Lin, Ying-Wu; He, Bo] Univ South China, Sch Chem & Chem Engn, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang City 421001, Hunan, Peoples R China.
通讯机构：
[Xiao, XL; Liao, LF] U;Univ South China, Sch Chem & Chem Engn, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang City 421001, Hunan, Peoples R China.
关键词：
Uranium;Resonance fluorescence chemosensor;Heterobinuclear complex;Di-tetradentate macrocyclic ligand;Europium
摘要：
In this paper, we synthesized and characterized a di-tetradentate macrocyclic ligand as a novel resonance fluorescence probe for the determination of uranium. The ligand contains two tetradentate ligand moieties and can chelate two cations to form binuclear complex. We found that when the ligand only chelates a uranyl ion or europium (III) ion, the formed complex can only produce weak resonance fluorescence. When the ligand chelates simultaneously uranyl and europium (III) to form heterobinuclear complex, the formed complex can produce strong resonance fluorescence due to the cation-cation interaction between uranyl and europium (III). Based on this finding, we established a resonance fluorescence chemosensor for the determination of uranium (VI) by utilizing the formation of the heterobinuclear complex. Under optimal conditions, the linear range for the determination of uranium (VI) is 0.008-1.2 nmol mL(-1) with a detection limit of 0.002 nmol mL(-1). The method has been applied to determine uranium (VI) in environmental water samples with the recoveries between 95.7% and 103.6%. (C) 2018 Elsevier B.V. All rights reserved.
语种：
英文
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Effect of bicarbonate on aging and reactivity of nanoscale zerovalent iron (nZVI) toward uranium removal
作者：
Hua, Yilong;Wang, Wei;Huang, Xiaoyue;Gu, Tianhang;Ding, Dexin;...
期刊：
Chemosphere ,2018年201(Jun.):603-611 ISSN：0045-6535
通讯作者：
Ling, Lan;Zhang, Wei-xian
作者机构：
[Hua, Yilong; Huang, Xiaoyue; Zhang, Wei-xian; Ling, Lan; Zhang, WX; Gu, Tianhang] Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resource Reuse, 1239 Siping Rd, Shanghai 200092, Peoples R China.;[Wang, Wei] Tongji Univ, Sch Chem Sci & Engn, 1239 Siping Rd, Shanghai 200092, Peoples R China.;[Ding, Dexin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, 28 West Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ling, L; Zhang, WX] T;Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resource Reuse, 1239 Siping Rd, Shanghai 200092, Peoples R China.
关键词：
Nanoscale zerovalent iron (nZVI);Aging;Bicarbonate;Heavy metals;Uranium
摘要：
Bicarbonate, ubiquitous in natural and waste waters is an important factor regulating the rate and efficiency of pollutant separation and transformation. For example, it can form complexes with U(VI) in the aqueous phase and at the solid-water interface. In this work, we investigated the effect of bicarbonate on the aging of nanoscale zero-valent (nZVI) in the context of U(VI) reduction and removal from wastewater. For fresh nZVI, over 99% aqueous uranium was separated in less than 10 min, of which 83% was reduced from U(VI) to U(IV). When nZVI was aged in water, its activity for U(VI) sequestration and reduction was significantly reduced. Batch experiments showed that for nZVI aged in the presence of 10 mM bicarbonate, only 20.3% uranium was reduced to U(IV) after 6 h reactions. Characterizations of the iron nanoparticles with spherical aberration corrected scanning transmission electron microscopy (Cs-STEM) suggest that in fresh nZVI, uranium was concentrated at the nanoparticle center; whereas in nZVI aged in bicarbonate, uranium was largely deposited on the outer surface of the nanoparticles. Furthermore, aged nZVI without bicarbonate contained more lepidocrocite (γ-FeOOH) while aged nZVI in the presence of bicarbonate had more magnetite/maghemite (Fe3O4/γ-Fe2O3). This could be attributed to the formation of carbonate green rust and pH buffer effect of [Figure presented]. Primary mechanisms for U(VI) removal with nZVI include reduction, sorption and/or precipitation. Results demonstrate that bicarbonate alter the aging products of nZVI, and reduces the separation efficiency and reduction capability for uranium removal. © 2018
语种：
英文
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Preparation and application of a carbon paste electrode modified with multi-walled carbon nanotubes and boron-embedded molecularly imprinted composite membranes
作者：
Wang, Hongjuan;Qian, Duo;Xiao, Xilin* ;Deng, Chunyan;Liao, Lifu;...
期刊：
Bioelectrochemistry ,2018年121:115-124 ISSN：1567-5394
通讯作者：
Xiao, Xilin;Deng, Jian
作者机构：
[Xiao, XL; Deng, Jian; Wang, Hongjuan; Xiao, Xilin; Qian, Duo; Liao, Lifu; Lin, Ying-Wu] Univ South China, Sch Chem & Chem Engn, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Deng, Chunyan] Cent S Univ, Coll Chem & Chem Engn, Key Lab Resources Chem Nonferrous Met, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Xiao, XL; Deng, J] U;Univ South China, Sch Chem & Chem Engn, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Tinidazole;Density functional theory;Multi-walled carbon nanotubes;Boron-embedded molecular imprinting composite membrane;Electrochemical sensor
摘要：
An innovative electrochemical sensor was fabricated for the sensitive and selective determination of tinidazole (TNZ), based on a carbon paste electrode (CPE) modified with multi-walled carbon nanotubes (MWCNTs) and boron-embedded molecularly imprinted composite membranes (B-MICMs). Density functional theory (DFT) calculations were carried out to investigate the utility of template-monomer interactions to screen appropriate monomers for the rational design of B-MICMs. The distinct synergic effect of MWCNTs and B-MICMs was evidenced by the positive shift of the reduction peak potential of TNZ at B-MICMs/MWCNTs modified CPE (B-MICMs/MWCNTs/CPE) by about 200 mV, and the 12-fold amplification of the peak current, compared with a bare carbon paste electrode (CPE). Moreover, the coordinate interactions between trisubstituted boron atoms embedded in B-MICMs matrix and nitrogen atoms of TNZ endow the sensor with advanced affinity and specific directionality. Thereafter, a highly sensitive electrochemical analytical method for TNZ was established by different pulse voltammetry (DPV) at B-MICMs/MWCNTs/CPE with a lower detection limit (1.25 × 10−12 mol L−1) (S/N = 3). The practical application of the sensor was demonstrated by determining TNZ in pharmaceutical and biological samples with good precision (RSD 1.36% to 3.85%) and acceptable recoveries (82.40%–104.0%). © 2017 Elsevier B.V.
语种：
英文
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耐冷嗜酸硫杆菌快速氧化地浸采铀吸附尾液中Fe~(2+)
作者：
王清良;陈鹏;胡鄂明;李乾;王红强;...
期刊：
化工进展 ,2018年37(10):3995-4005 ISSN：1000-6613
通讯作者：
Wang, Qingliang(nhwql@sina.com)
作者机构：
[王清良; 陈鹏; 胡鄂明; 李乾] Nuclear Resources Engineering College, University of South China, Hengyang;Hunan;421001, China;Coorperative Innovation Center of Hunan Province for Nuclear Fuel Cycle Technology & Equipment, Hengyang;[王红强] Environmental and Safety Engineering College, University of south China, Hengyang
关键词：
耐冷嗜酸硫杆菌;生物反应器;生物陶粒;地浸采铀;氧化剂;吸附尾液
摘要：
为解决中温菌在低温吸附尾液中作氧化剂时生长繁殖慢、氧化Fe~(2+)速率低等问题,实验结合新疆某酸法地浸采铀现场生产实际,选取耐冷嗜酸硫杆菌作为氧化剂,以生物陶粒为挂膜载体,在生物反应器内对细菌进行固定化培养,研究了细菌快速氧化吸附尾液中Fe~(2+)规律.实验结果表明,选用的生物陶粒具有高孔隙率、高透水性、高吸附性和高比表面积等特点,对细菌有较好的吸附固着效果,有利于细菌的生长繁殖,提高了细菌氧化Fe~(2+)速率;生物陶粒在pH 1.6~1.7的吸附尾液中具有较强的耐酸性和稳定性;当通气量为20L/h、吸附尾液温度为17~19℃、流量为500L/h时,生物反应器连续氧化Fe~(2+)速率达到0.85g/(L·h);与H_2O_2作氧化剂相比,可以节约费用约72.6%,为实现细菌作氧化剂的工业化应用提供了有力依据.
语种：
中文
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Experimental investigation on damage evolution behaviour of a granitic rock under loading and unloading
作者：
Dai Bing* ;Zhao Guo-yan;Konietzky, H.;Wasantha, P. L. P.
期刊：
中南大学学报(英文版) ,2018年25(5):1213-1225 ISSN：2095-2899
通讯作者：
Dai Bing
作者机构：
[Dai Bing] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.;[Zhao Guo-yan; Dai Bing] Cent S Univ, Sch Resources & Safety Engn, Changsha 410001, Hunan, Peoples R China.;[Konietzky, H.; Wasantha, P. L. P.; Dai Bing] TU Bergakad, Geotech Inst, D-09599 Freiberg, Germany.
通讯机构：
[Dai Bing] U;[Dai Bing] C;[Dai Bing] T;Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.;Cent S Univ, Sch Resources & Safety Engn, Changsha 410001, Hunan, Peoples R China.
关键词：
damage evolution;loading and unloading;granitic rock;triaxial testing
摘要：
In-situ rock failures can result from stress changes due to pure loading and/or unloading. Understanding of the damage evolution behavior in brittle rocks during loading and unloading is imperative for the designs of rock structures. In this paper, we investigate the damage evolution characteristics of a granitic rock during loading and unloading after a series of triaxial experiments performed at different confining pressures. The axial stress-axial strain variations of the tested specimens revealed that the specimens undergoing unloading fail with a lower axial strain compared to the specimens failed purely by loading. Higher confining pressures were observed to exacerbate the difference. Volumetric strain versus axial strain curves indicated that the curves reverse the trend with the beginning of major damage of specimens. We suggest here a new form of equation to describe the secant modulus variation of brittle rocks against the axial stress for the unloading process. Failure mechanisms of tested specimens showed two distinct patterns, namely, specimens under pure loading failed with a single distinct shear fracture while for the unloading case specimens displayed multiple intersecting fractures. In addition, analysis of the evolution of dissipation and elastic energy during deformation of the specimens under loading and unloading conditions showed differentiable characteristics. Moreover, we evaluated the variations of two damage indices defined based on the energy dissipation and secant modulus evolution during deformation and observed that both of them satisfactorily distinguish key stages of damage evolution.
语种：
英文
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The mechanism of vibrations-aided gravitational flow with overhanging style in hopper
作者：
Zhang, Chunyang* ;Qiu, Caimou;Pu, Chengzhi;Fan, Xiang;Cao, Ping
期刊：
Powder Technology ,2018年327:291-302 ISSN：0032-5910
通讯作者：
Zhang, Chunyang
作者机构：
[Zhang, Chunyang; Qiu, Caimou] Wuhan Univ Technol, Sch Resources & Environm Engn, Wuhan 430070, Hubei, Peoples R China.;[Pu, Chengzhi] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.;[Fan, Xiang] Changan Univ, Sch Highway, Xian 710064, Shaanxi, Peoples R China.;[Cao, Ping] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.
通讯机构：
[Zhang, Chunyang] W;Wuhan Univ Technol, Sch Resources & Environm Engn, Wuhan 430070, Hubei, Peoples R China.
关键词：
Similarity model tests;Numerical simulation;Flow-aiding vibrator;Overhanging style;Field tests
摘要：
Arching, blocking, and sticking might be frequently encountered in hopper. Studies are carried out in order to solve these problems in Luoyang Bauxite Mine, China. The results of similarity model tests show that factors affecting flowability of particles are mainly friction and cohesion, when the moisture content changes from 82% to 10.8%, the influence of friction and cohesion on the flowability of particles becomes increasingly unfavorable, particles are easier to stay in the corners. In addition, the discharge effect is also affected by friction coefficient of the inner wall. In the numerical simulation, vibration is imposed by means of two blue balls fixed in the corners, where the flowability of particles is proved to be the worst. Results indicate that, no matter whether vibration is added or not, the total numbers of discharged particles and contacts change linearly with time steps, the contact forces between particles and walls are generally greater than that between particles. Compared with gravity discharge, the average velocities of the particles are obviously increased with the help of vibrations, especially in the corners of the hopper. The contact forces between particles as well as between particles and walls are optimized, that is, larger fluctuations of the contact forces are exhibited periodically, mainly because the contacts are greatly damaged by vibrations, therefore, the possibility of arching is limited effectively. The results of the studies reflect the mechanism of vibrations-aided gravitational flow and provide a theoretical basis for the design of a new vibrator. In combination with flow characteristics of particles, influencing factors of particle flow and theory of granular mechanics, a new flow-aiding vibrator with overhanging style in hopper is designed. In field tests, it has been proved to be a safe and effective device for solving problems of arching, blocking and sticking. (C) 2018 Elsevier B.V. All sights reserved.
语种：
英文
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浅埋石膏矿顶板破断机理及应用研究
作者：
章求才;贺桂成;黄炳香;张志军
期刊：
采矿与安全工程学报 ,2018年35(4):773-779 ISSN：1673-3363
通讯作者：
He, Guicheng(hegc9210@163.com)
作者机构：
[章求才; 贺桂成; 张志军] School of Nuclear Resources Engineering, University of South China, Hengyang;Hunan;421001, China;[黄炳香] State Key Laboratory of Coal Resources and Safe Mining, China University of Mining & Technology, Xuzhou;Jiangsu
通讯机构：
[He, G.] S;School of Nuclear Resources Engineering, University of South China, Hengyang, Hunan, China
关键词：
石膏矿;弹性薄板;直接顶;破断判据;破断特征
摘要：
采用弹性力学理论,将石膏矿采空区直接顶视为四边固支的弹性薄板,建立了直接顶破断的力学模型,分析其在法向和切向荷载作用下的临界荷载及影响因素,确定其破断判据及破断特征,并应用于衡山某石膏矿试验采场,分析其稳定性,得到了该矿最合适的采场结构参数。研究结果表明:直接顶承受的最大拉应力随采场埋深及矿房长度与矿房跨度比值的增加而增大,随直接顶厚度的增加而减少;当矿房长度和矿房跨度接近时,直接顶承受的最大拉应力较小;当直接顶承受的最大拉应力大于其抗拉强度时,直接顶下表面中部岩体开始产生裂隙,裂隙沿四周向直接顶边界发展;随后直接顶上表面中部靠近工作面处的岩体产生裂隙,裂隙沿倾向向直接顶边界发展;最后直接顶上表面中部靠近矿房进口处岩体产生裂隙,至此直接顶完全破断。矿房跨度小于10 m,直接顶厚度大于2 m,是衡山石膏矿最合适的采场结构参数。
语种：
中文
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Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study
作者：
Kong, Xiang-He;Wu, Qun-Yan;Wang, Cong-Zhi;Lan, Jian-Hui;Chai, Zhi-Fang;...
期刊：
JOURNAL OF PHYSICAL CHEMISTRY A ,2018年122(18):4499-4507 ISSN：1089-5639
通讯作者：
Shi, Wei-Qun
作者机构：
[Wu, Qun-Yan; Kong, Xiang-He; Chai, Zhi-Fang; Wang, Cong-Zhi; Lan, Jian-Hui; Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.;[Nie, Chang-Ming; Kong, Xiang-He] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.;[Chai, Zhi-Fang] Soochow Univ, Sch Radiol & Interdisciplinary Sci RAD X, Suzhou 215123, Peoples R China.;[Chai, Zhi-Fang] Soochow Univ, Collaborat Innovat Ctr Radiat Med Jiangsu Higher, Suzhou 215123, Peoples R China.
通讯机构：
[Shi, Wei-Qun] C;Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.
会议名称：
18th Meeting on Time-Resolved Vibrational Spectroscopy (TRVS)
会议时间：
2017
会议地点：
Cambridge, ENGLAND
会议主办单位：
[Kong, Xiang-He;Wu, Qun-Yan;Wang, Cong-Zhi;Lan, Jian-Hui;Chai, Zhi-Fang;Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.^[Kong, Xiang-He;Nie, Chang-Ming] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.^[Chai, Zhi-Fang] Soochow Univ, Sch Radiol & Interdisciplinary Sci RAD X, Suzhou 215123, Peoples R China.^[Chai, Zhi-Fang] Soochow Univ, Collaborat Innovat Ctr Radiat Med Jiangsu Higher, Suzhou 215123, Peoples R China.
摘要：
Separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is one of the most important steps in spent nuclear fuel reprocessing. However, it is very difficult and challenging to separate them due to their similar chemical properties. Recently the pyridylpyrazole ligand (PypzH) has been identified to show good separation ability toward Am(III) over Eu(III). In this work, to explore the Am(III)/Eu(III) separation mechanism of PypzH at the molecular level, the geometrical structures, bonding nature, and thermodynamic behaviors of the Am(III) and Eu(III) complexes with PypzH ligands modified by alkyl chains (Cn-PypzH, n = 2, 4, 8) have been systematically investigated using scalar relativistic density functional theory (DFT). According to the NBO (natural bonding orbital) and QTAIM (quantum theory of atoms in molecules) analyses, the M-N bonds exhibit a certain degree of covalent character, and more covalency appears in Am-N bonds compared to Eu-N bonds. Thermodynamic analyses suggest that the 1:1 extraction reaction, [M(NO<inf>3</inf>)(H<inf>2</inf>O)<inf>6</inf>]<sup>2+</sup>+ PypzH + 2NO<inf>3</inf><sup>-</sup>→M(PypzH)(NO<inf>3</inf>)<inf>3</inf>(H<inf>2</inf>O) + 5H<inf>2</inf>O, is the most suitable for Am(III)/Eu(III) separation. Furthermore, the extraction ability and the Am(III)/Eu(III) selectivity of the ligand PypzH is indeed enhanced by adding alkyl-substituted chains in agreement with experimental observations. Besides this, the nitrogen atom of pyrazole ring plays a more significant role in the extraction reactions related to Am(III)/Eu(III) separation compared to that of pyridine ring. This work could identify the mechanism of the Am(III)/Eu(III) selectivity of the ligand PypzH and provide valuable theoretical information for achieving an efficient Am(III)/Eu(III) separation process for spent nuclear fuel reprocessing.<br/> ©2018 American Chemical Society.
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英文
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Construction of recombinant bioleaching bacteria Thiobacillus ferrooxidans with fluoride-resistant activity
作者：
Cao, Yun-Chang;Wen, Hong-Bo;Hu, Nan;Wang, Yong-Dong;Li, Gaung-Yue;...
期刊：
American Journal of Biochemistry and Biotechnology ,2018年14(2):145-153 ISSN：1553-3468
通讯作者：
Ding, De-Xin(dingdxzzz@163.com)
作者机构：
[Cao, Yun-Chang; Hu, Nan; Wang, Yong-Dong; Li, Gaung-Yue; Ding, De-Xin] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 28 West Changsheng Rd, Hengyang;Hunan;421001, China;[Wen, Hong-Bo] Department of Biochemistry and Molecular Biology, School of Pharmaceutical and Biological Science, University of South China, 28 West Changsheng Rd, Hengyang;[Cao, Yun-Chang; Wen, Hong-Bo; Hu, Nan; Wang, Yong-Dong; Li, Gaung-Yue; Ding, De-Xin] Hunan
通讯机构：
[Ding, D.-X.] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 28 West Changsheng Rd, Hengyang, Hunan, China
关键词：
Bioleaching bacteria;Conjugation transfer;Flr-4 gene;Fluoride resistance;Genetic modification;Thiobacillus ferrooxidans
摘要：
Thiobacillus ferrooxidans is an important bioleaching bacterium, widely used in leaching, recovery of low-grade metals and environmental bioremediation. In bio-metallurgy industry, fluoride existing in some hard rock uranium deposits in south China severely affects the bacteria viability and inhibit leaching reproduction. In this study, the flr-4 gene that has strong resistance to fluorine ion in Caenorhabditis elegans, was cloned into pET30a vector and expressed in E. coli BL21. the ability of fluoride resistance in E. coli was increased obviously. To increase the fluorideresistance of bioleaching bacterium T. ferrooxidans strain 1 (T.f1), the flr-4 shuttle recombinant plasmid pJRD215-flr-4 was constructed and transferred into T.f1 by conjugation. pJRD215-flr-4 was stable in T.f1 with more than 70% retention after 50 generations. Recombinant T.f1 was tolerant to fluorine ions and grew well under fluoride (F-) stress especially at F- concentrations ranging from 10 mg/L to 60 mg/L. © 2018 Yun-Chang Cao, Hong-Bo Wen, 1Nan Hu, Yong-Dong Wang, Guang-Yue Li and De-Xin Ding.
语种：
英文
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氧化石墨烯/有机改性膨润土复合材料的制备及其对Cd(Ⅱ)的吸附
作者：
唐振平;毕玉玺;刘迎九;滑熠龙;凌辉;...
期刊：
复合材料学报 ,2018年35(11):3196-3204 ISSN：1000-3851
通讯作者：
Xie, Shuibo(xiesbmr@263.net)
作者机构：
[唐振平; 毕玉玺; 刘迎九; 凌辉; 谢水波] Hu'nan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hengyang;421001, China;Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;[滑熠龙] State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai;200092, China
通讯机构：
[Xie, S.] H;Hu'nan Provincial Key Laboratory of Pollution Control and Resources Technology, University of South China, Hengyang, China
关键词：
氧化石墨烯;有机改性膨润土;吸附;解吸;共存离子
摘要：
以氧化石墨烯(GO)、膨润土(Bent)、十六烷基三甲基溴化铵(CTAB)为原料,合成了GO/有机改性Bent(OM-Bent)复合材料,用其处理浓度为10mg·L~(-1)的含Cd(Ⅱ)废水。研究了GO/OM-Bent复合材料中GO含量、pH、GO/OM-Bent复合材料投加量、反应时间、Cd(Ⅱ)初始浓度及共存离子对GO/OM-Bent复合材料吸附Cd(Ⅱ)的影响。结果表明:在pH值为6、GO质量分数为30wt%、GO/OM-Bent复合材料投加量为200mg·L~(-1)时,GO/OM-Bent复合材料吸附Cd(Ⅱ)效果最佳,120min即达到平衡,较同等条件下OM-Bent和GO单独作用时Cd(Ⅱ)吸附量分别高12.01mg·g~(-1)和5.39mg·g~(-1);准二级动力学模型能很好地描述其吸附过程,吸附等温线符合Langmuir模型,温度为303K时,GO/OM-Bent复合材料对Cd(Ⅱ)的最大吸附量为133.33mg·g~(-1)。解吸实验结果表明,经5次吸附-解吸循环实验后,Cd(Ⅱ)的吸附率仍高达83.5%,说明GO/ OM-Bent复合材料具有很好的循环再生性能。
语种：
中文
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富集的硫酸盐还原菌沉积物生物还原地下水中U(Ⅵ)的实验研究
作者：
李殿鑫;胡南;黄超;丁德馨;李广悦;...
期刊：
化工学报 ,2018年69(8):3619-3625 ISSN：0438-1157
通讯作者：
Ding, Dexin(dingdxzzz@163.com)
作者机构：
[李殿鑫; 胡南; 黄超; 丁德馨; 李广悦; 王永东] Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;Hunan;421001, China;Hunan Province Key Laboratory of Green Development Technology for Extremely Low Grade Uranium Resources, University of South China, Hengyang;[李殿鑫; 胡南; 黄超; 丁德馨; 李广悦; 王永东] Hunan
关键词：
废水;沉积物;还原;修复
摘要：
通过添加富集得到的含有丰富的硫酸盐还原菌的沉积物到沉积物-地下水微模型中,并添加乙醇作为碳源,分别与接种硫酸盐还原菌并添加碳源组和仅添加碳源组相比较,研究富集的硫酸盐还原菌沉积物对地下水中U(Ⅵ)还原的作用。结果表明,添加硫酸盐还原菌沉积物组、接种硫酸盐还原菌组和对照组中的铀浓度分别在第19、22和28 d下降至GB 23727—2009规定的0.05 mg·L~(–1)排放标准以下。各组沉积物中具有还原U(Ⅵ)功能的微生物群落的多样性差异较小。添加硫酸盐还原菌沉积物组、接种硫酸盐还原菌组和对照组的沉积物中具有还原U(Ⅵ)功能的微生物群落的丰度分别为35.3%、32.5%和13.1%。由此可见,富集的硫酸盐还原菌沉积物增加了微模型中具有还原U(Ⅵ)功能的微生物群落的丰度,从而促进了U(Ⅵ)的还原。
语种：
中文
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Transformation of uranium species in soil during redox oscillations
作者：
Fu, Haiying;Zhang, Hui;Sui, Yang;Hu, Nan;Ding, Dexin* ;...
期刊：
Chemosphere ,2018年208(Oct.):846-853 ISSN：0045-6535
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zhang, Hui; Ye, Yongjun; Li, Guangyue; Dai, Zhongran; Hu, Nan; Wang, Yongdong; Fu, Haiying] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Ding, Dexin; Ye, Yongjun; Sui, Yang; Fu, Haiying] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Sui, Yang] Hunan Taohuajiang Nucl Power Co Ltd, Yiyang 413000, 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：
Redox cycling;Uranium speciation;Stable U(IV);Chemical extraction;Paddy soil
摘要：
Redox oscillation is commonly found in near-surface environment, where soils are often polluted with many redox active contaminants, including uranium (U). In order to investigate the transformation of U species in near-surface soil under redox oscillations conditions, redox oscillations and reduction experiments were performed, biogeochemical parameters and native microbial community composition were monitored, main elements on the surface of solid-phase were analyzed by XPS, and labile U(IV) species and stable U(IV) species in solid-phase were provisionally defined using an anoxic 1 M sodium bicarbonate extraction. It was found that redox oscillations slightly increased the water-soluble U but significantly increased the stable U(IV) species (P < 0.05) in soil. In reduction experiment, there was upper limit value for percentage of stable U(IV) species, and the labile U(IV) species could not transform to stable U(IV) species in a short period of time under reduction conditions. The redox transition of Fe enriched on the surface of soil and the conversion of microbial community composition played a major role in speciation transformation of U under redox oscillations conditions. In addition, sequential extraction revealed that the increase of stable U(IV) species content reflected the U speciation transition from acetate extract to more recalcitrant hydroxylamine extract. The finding provides a potential method for improving the stability of U when bio-reduction is used to remediate the U-contaminated soils. © 2018 Elsevier Ltd
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英文
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Geochronology and geochemistry of porphyritic intrusions in the Duolong porphyry and epithermal Cu-Au district, central Tibet: Implications for the genesis and exploration of porphyry copper deposits
作者：
Sun, Jia* ;Mao, Jingwen* ;Beaudoin, Georges;Duan, Xianzhe* ;Yao, Fojun;...
期刊：
Ore Geology Reviews ,2017年80:1004-1019 ISSN：0169-1368
通讯作者：
Sun, Jia;Mao, Jingwen;Duan, Xianzhe
作者机构：
[Mao, Jingwen; Ouyang, Hegen; Sun, Jia; Yao, Fojun; Sun, J; Mao, JW] Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.;[Sun, Jia; Meng, Xuyang] China Univ Geosci, Sch Geosci & Resources, Beijing 100083, Peoples R China.;[Beaudoin, Georges] Univ Laval, Dept Geol & Genie Geol, Quebec City, PQ G1V 0A6, Canada.;[Duan, Xianzhe] Univ South China, Sch Nucl Resource Engn, Hengyang 421001, Peoples R China.;[Wu, Yue] Yangtze Univ, Sch Earth Environm & Water Resource, Wuhan 430100, Peoples R China.
通讯机构：
[Sun, J; Mao, JW] C;[Duan, Xianzhe] U;Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.;Univ South China, Sch Nucl Resource Engn, Hengyang 421001, Peoples R China.
关键词：
Amphibole;Emplacement depth;Magnetite;Mineral exploration;Porphyry copper deposits
摘要：
The Duolong district in central Tibet hosts a number of porphyry as well as high sulfidation epithermal copper–gold deposits and prospects, associated with voluminous calc-alkaline volcanism and plutonism. In this study, we present new geochronological, geochemical, isotopic and mineralogical data for both economically mineralized and barren porphyritic intrusions from the Duobuza and Naruo porphyry Cu–Au deposits. Zircon U–Pb analyses suggest the emplacement of economically mineralized granodiorite porphyry and barren granodiorite porphyry at Naruo deposit took place at 119.8 ± 1.4 Ma and 117.2 ± 0.5 Ma, respectively. Four molybdenite samples from the Naruo deposit yield an isochron Re–Os age of 119.5 ± 3.2 Ma, indicating mineralization occurred synchronously with the emplacement of the early granodiorite porphyry. At Duobuza deposit, the barren quartz diorite porphyry intruded at 119.5 ± 0.7 Ma, and two economically mineralized intrusions intruded at 118.5 ± 1.2 Ma (granodiorite porphyry) and 117.5 ± 1.2 Ma (quartz diorite porphyry), respectively. Petrographic investigations and geochemical data indicate that all of the porphyritic intrusions were oxidized, water rich, and subduction-related calc-alkaline magmas. Zircons from the porphyritic intrusions have a wide range in the Ε<inf>Hf</inf>(0–11.1) indicating that they were sourced from mixing of mantle-derived mafic, and crust-derived felsic melts. Moreover, the variation of trace element content of plagioclase phenocrysts indicates that the magma chambers were recharged by mafic magmas. Comparison of the composition of amphibole phenocrysts indicates the porphyry copper–gold mineralization at Duolong was generated in magma chambers at low crystallization temperatures and pressures (754°to 791 °C, 59 M to 73 MPa, n = 8), and under highly oxidizing conditions (ΔNNO 2.2 to 2.7, n = 8). In contrast, barren intrusions were sourced from the magma chambers with higher crystallization temperatures and pressures (816°to 892 °C, 111 to 232 MPa, n = 22) that were less oxidizing (ΔNNO 0.6 to 1.6, n = 22). The requirement for a thermal contrast is supported by the declining of Ti content in magnetite crystals in barren intrusions (12,550 to 34,200 ppm) versus those from economically mineralized intrusions (600 to 3400 ppm). Moreover, the V content in magnetite crystals from economically mineralized intrusions (990 to 2510 ppm) is lower than those recorded from barren intrusions (2610 to 3510 ppm), which might reflect the variation in oxidation state of the magma. The calculated water solubility of the magma forming the economically mineralized intrusions (3.2–3.7 wt%) is lower than that of magma forming the barren intrusions (4.6–6.4 wt%). Based on the chemical–physical characteristics of economically mineralized magma, our study suggests that the development of porphyry Cu–Au mineralization at Duolong was initiated by shallow-level emplacement of a magma that crystallized at lower temperatures and pressures. Experimental studies show that copper and water solubilities in silicate melts decrease with falling temperatures and pressures, indicating metals and ore-forming fluids are more likely to be released from a magma reservoir emplaced at shallow crustal levels. We propose the magnetite might be a convenient exploration tool in the search for porphyry copper mineralization because the variations in Ti and V content of mineral concentrates and rock samples are indicative of barren versus mineralized intrusions. ©2016 Elsevier B.V.
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