Experimental study of the effect of seepage on radon exhalation in circular tubular porous emanation media:
作者：
Ye, Yongjun;Wu, Wenhao;Huang, Chunhua* ;Kearfott, Kimberlee J.
期刊：
Indoor and Built Environment ,2019年29(5):701-710 ISSN：1420-326X
通讯作者：
Huang, Chunhua
作者机构：
[Ye, Yongjun; Wu, Wenhao] Univ South China, Sch Resource Environm & Safety Engn, Hengyang, Peoples R China;[Ye, Yongjun] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang, Peoples R China;[Ye, Yongjun; Kearfott, Kimberlee J.] Univ Michigan, Dept Nucl Engn & Radiol Sci, Ann Arbor, MI 48109 USA;[Huang, Chunhua] Univ South China, Sch Architecture, Hengyang 421001, Hunan, Peoples R China
通讯机构：
[Huang, Chunhua] U;Univ South China, Sch Architecture, Hengyang 421001, Hunan, Peoples R China.
关键词：
Radon;Diffusion;Seepage velocity;Underground tunnels;Mathematical model;Radon exhalation;Porous emanation media
摘要：
Radium, which is naturally present in many rocks, decays to the radioactive gas radon, which is then exhaled from the surface of underground tunnels and other underground buildings and is a major source of human exposure to radioactivity. A mathematical model for the migration of radon from a circular tubular emanation medium was established based on the seepage–diffusion migration theory for radon in porous emanation media, such as artificial retaining walls and the surrounding rocks in these locations. An analytical solution for the distribution of radon concentrations and the calculation formula for the radon exhalation rate under steady-state conditions were then obtained. An experimental device was designed to determine the radon exhalation rate under different pressure gradients. The theoretical calculation values for the radon exhalation rate and the total amount of radon exhalation are in good agreement with the experimental results. The radon exhalation rate at the low-pressure side increases with an increase in seepage velocity (pressure difference), while the radon exhalation rate at the high-pressure side is on the contrary. The total amount of radon exhalation increased over time with an increase in the seepage velocity and tended towards a maximum value. © The Author(s) 2019.
语种：
英文
展开
Evaluation of electrokinetics coupled with a reactive barrier of activated carbon loaded with a nanoscale zero-valent iron for selenite removal from contaminated soils
作者：
Huang, Tao* ;Liu, Longfei;Zhang, Shuwen;Xu, Jiaojiao
期刊：
Journal of Hazardous Materials ,2019年368:104-114 ISSN：0304-3894
通讯作者：
Huang, Tao
作者机构：
[Xu, Jiaojiao; Liu, Longfei; Huang, Tao] 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, Tao] C;Changshu Inst Technol, Sch Chem & Mat Engn, Changshu 215500, Jiangsu, Peoples R China.
关键词：
Activated charcoal;Electrokinetics;Nanoscale zero-valent iron;Permeable reactive barrier;Selenite removal and catalytic recovery
摘要：
The range between dietary deficient and toxic levels for selenium is quite narrow. In this study, the synergistic effects of electrokinetics (EK) and a permeable reactive barrier (PRB) on the reductive sequestration of Se(IV) oxyanions from spiked soils were investigated in detail. Activated charcoal (AC)-supported Fe(II) and nanoscale zero-valent iron (nZVI) were prepared as the PRB media for use in an electrolyzer. In aqueous equilibrium adsorption tests, the AC-supported nZVI medium had a higher adsorption capacity than that of the other adsorbents. The Se(IV) removal isotherms were well-fitted using the Langmuir model. The Se(IV) removal rates were accurately predicted by both pseudo-first- and pseudo-second-order kinetic models. For the coupled systems, a moderate increase in the number of PRBs and decrease in the PRB thickness in the electrolyzer enhanced the removal and catalytic recovery of Se(IV) from the spiked soil samples. A Se(VI) removal efficiency of approximately 95% and Se(VI) reduction efficiency of 90% were achieved in the optimized electrochemical system. The Se(IV) species were reduced to Se degrees and FeSe by the AC-supported nZVI regardless of the pH distribution. The experimental results provide guidance for the multichannel recovery of Se from abandoned ore tailings or solid wastes.
语种：
英文
展开
Enhancement of repeated applications of chelates on phytoremediation of uranium contaminated soil by Macleaya cordata.
作者：
Hu, Nan;Lang, Tao;Ding, Dexin* ;Hu, Jingsong;Li, Changwu;...
期刊：
Journal of Environmental Radioactivity ,2019年199-200:58-65 ISSN：0265-931X
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zhang, Hui; Li, Changwu; Li, Guangyue; Hu, Nan; Hu, Jingsong] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, 28 West Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.;[Lang, Tao] Jiangxi Nucl Ind Geol Bur, Brigade 264, Ganzhou 341000, Jiangxi, Peoples R China.
通讯机构：
[Ding, Dexin] 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：
Antioxidant enzymes;Chelates;Macleaya cordata;Phytoremediation;Uranium
摘要：
A greenhouse pot experiment was performed to investigate the enhancement of repeated applications of citric acid (CA), ethylenediamine disuccinic acid (EDDS), and Oxalic acid (OA) on phytoremediation of uranium (U) contaminated soil by Macleaya Cordata. The chelates followed the order CA > EDDS > OA in terms of the enhancement on uranium uptake by M. cordata. The repeated applications of the chelates were found to be more effective than the one time application at the equal dose as the U concentration of soil solution increased significantly from the 8th to 14th day. The repeated applications of 10 mmol kg(-1) CA promoted the solubilization of U in the U-contaminated soil by significantly decreasing the pH of soil solution, achieved the maximum U concentration of soil solution (1463.6 microg L(-1)), bioconcentration factors (BCFs, 11.4), bioaccumulation factors (BAFs, 21.4) and transfer factors (TFs, 1.9), which were 215.2, 5.7, 30.6 and 16.3 times as compared with the control group, respectively. The three applied chelates significantly affected the activities of the antioxidant enzymes in the leaves. Repeated applications of CA further enhanced the activities of the antioxidant enzymes in the leaves of M. cordata as compared with the control, EDDS and OA, mitigated the oxidative stress induced by uranium and chelates, and maximized the enhancement on the uranium uptake, which will be beneficial for the enhancement on the phytoremediation of uranium contaminated soil by U hyperaccumulating plants. These results indicated that the phytoavailability of uranium in soil solution as well as the accumulation of U by M. cordata were both significantly increased after repeated applications of CA, and that the repeated applications of 10 mmol kg(-1) CA increased the activities of the antioxidant enzymes and promoted U accumulation by M. cordata. The study provided an environmentally friendly alternative for the enhancement on the phytoremediation of uranium contaminated soil using M. cordata.
语种：
英文
展开
回收CRT锥玻璃部分替代高密度磁铁矿砂在防辐射混凝土中应用的可行性
作者：
Liu, Hua-liang;Shi, Jian-jun;Qu, Hui-qiong;Ding, De-xin*
期刊：
中国有色金属学报(英文版) ,2019年29(4):831-839 ISSN：1003-6326
通讯作者：
Ding, De-xin
作者机构：
[Shi, Jian-jun; Liu, Hua-liang; Ding, De-xin] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.;[Shi, Jian-jun; Liu, Hua-liang] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Qu, Hui-qiong; Ding, De-xin] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Ding, De-xin] C;[Ding, De-xin] U;Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.;Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.
关键词：
cathode ray tube;funnel glass;concrete;gamma-ray;radiation shielding;mechanical properties;Monte-Carlo N-Particle simulation
摘要：
The recycled cathode ray tube (CRT)funnel glass was used as replacement of magnetite sand in the concrete, and its mass replacement rates were 0, 20%, 40% and 60%, respectively. The flowability, apparent density and mechanical properties of the radiation shielding concrete were investigated, while its γ-ray radiation shielding parameters such as linear and mass attenuation coefficients (μ and μm, respectively), thickness values of half-value layer (hHVL)and tenth-value layer (hTVL)were obtained by theoretical calculation, experiment and Monte−Carlo N-Particle (MCNP)simulation code. The experimental results show that the flowability of the concrete increases significantly, whilst its apparent density, compressive strength and static elastic modulus decrease slightly. The calculated, simulated and experimental μm, μ, hHVL and hTVL values of all concrete samples are very consistent at the same γ-ray photon energy, and it is feasible to use MCNP code to simulate γ-ray radiation shielding parameters of materials. The calculated results show that in a wide range of γ-ray photon energy, the μm value of the concrete with CRT funnel glass replacing magnetite sand is improved effectively, and its radiation shielding performances are the same as those of the control concrete (M−1). By comprehensively comparing the flowability, mechanical properties and γ-ray radiation shielding properties, the concrete samples with 20%−40% funnel glass as fine aggregate have good performances. © 2019 The Nonferrous Metals Society of China
语种：
英文
展开
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
展开
Poly (-cyclodextrin)/bentonite composite: synthesis mechanism and adsorption property for cesium in water
作者：
Liu, Hongjuan* ;Xie, Shuibo* ;Zhang, Xichen;Liu, Yingjiu;Zeng, Taotao
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年318(3):2117-2127 ISSN：0236-5731
通讯作者：
Liu, Hongjuan;Xie, Shuibo
作者机构：
[Liu, Hongjuan] Univ South China, Inst Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Liu, Hongjuan; Xie, Shuibo; Liu, HJ] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Xie, Shuibo; Liu, Yingjiu; Zhang, Xichen; Zeng, Taotao] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reu, Hengyang 421001, Peoples R China.
通讯机构：
[Liu, Hongjuan; Liu, HJ; Xie, SB; Xie, Shuibo] U;Univ South China, Inst Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reu, Hengyang 421001, Peoples R China.
关键词：
Bentonite;beta-CD/BNC;Cesium;Characterization;Adsorption
摘要：
A poly(β-Cyclodextrin)/bentonite composite (β-CD/BNC) were characterized by N2–BET measurement, scanning electron microscopy, energy dispersive spectrometer, fourier transform infrared spectroscopy, thermogravimetric analysis and X-ray photoelectron spectroscopy. Its synthesis mechanism of graft polymerisation was expounded. The maximum sorption capacities of Cs+ onto β-CD/BNC in absence and presence of Cl− and CO3 2− were 48.83 mg g−1, 48.90 mg g−1, and 46.19 mg g−1, respectively. The effect of Cl− and CO3 2− on Cs+ adsorption was not obvious. β-CD/BNC displayed good stability and reusability. The main adsorption mechanism of cesium by β-CD/BNC was ion exchange, and the surface coordination was subordinated mechanism. © 2018, Akadémiai Kiadó, Budapest, Hungary.
语种：
英文
展开
Experimental study on bioclogging in porous media during the radioactive effluent percolation
作者：
Gui, Rong;Pan, Yu-xiang;Ding, De-xin* ;Liu, Yong;Zhang, Zhi-jun*
期刊：
Advances in Civil Engineering ,2018年2018 ISSN：1687-8086
通讯作者：
Ding, De-xin;Zhang, Zhi-jun
作者机构：
[Gui, Rong; Ding, De-xin] Cent South Univ, Sch Resources & Safety Engn, Changsha 420083, Hunan, Peoples R China.;[Pan, Yu-xiang; Zhang, Zhi-jun; Gui, Rong; Liu, Yong; Ding, De-xin; Zhang, ZJ] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Pan, Yu-xiang; Zhang, Zhi-jun; Gui, Rong; Liu, Yong; Ding, De-xin; Zhang, ZJ] Univ South China, Nucl Resource Engn Coll, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, De-xin] C;[Ding, DX; Zhang, ZJ] U;Cent South Univ, Sch Resources & Safety Engn, Changsha 420083, Hunan, Peoples R China.;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;Univ South China, Nucl Resource Engn Coll, Hengyang 421001, Hunan, Peoples R China.
摘要：
The sand columns inoculated with the indigenous microorganism (Aspergillus Niger) were used to investigate the effect of bioclogging during the radioactive effluent percolation. The hydraulic gradient, volumetric flow rate, and uranyl ions concentration were monitored over time. The sand columns were operated with continuous radioactive effluent of uranium tailings reservoir. After 68 days, the hydraulic conductivity of the sand columns decreased more than 72%, and the adsorption rate of uranyl ions by Aspergillus Niger reached more than 90%. Environmental scanning electron microscope imaging confirmed the biofilm covering the surface of sand particles and connecting sand particles together, which resulted in a reduction of hydraulic conductivity. The results indicated that the propagation of Aspergillus Niger can clog the seepage channel and effectively adsorb the uranyl ions of radioactive effluent in the porous media, which provides a suitable measure for controlling the migration of radioactive effluent of uranium tailings reservoir into the subsurface environment. © 2018 Rong Gui et al.
语种：
英文
展开
Preparation of Polyamidoxime/Magnetic Graphene Oxide Composite and Its Application for Efficient Extraction of Uranium(VI) from Aqueous Solutions in an Ultrasonic Field
作者：
Dai, Zhongran;Zhang, Hui;Sui, Yang;Ding, Dexin* ;Li, Le
期刊：
Journal of Chemical and Engineering Data ,2018年63(11):4215-4225 ISSN：0021-9568
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zhang, Hui; Li, Le; Dai, Zhongran] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Sui, Yang] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Sui, Yang] Fujian Fuqing Nucl Power Co Ltd, Fuqing 350300, 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.
摘要：
In this work, the polyamidoxime functionalized magnetic graphene oxide (mGO-PAO) was prepared via the surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization, characterized by TEM, FT-IR, VSM, and TGA techniques, and applied for the extraction of uranium(VI) from aqueous solutions in an ultrasonic field. The effects of pH, contact time, initial uranium(VI) concentration, temperature, and competitive ions on the adsorption of U(VI) were investigated. The adsorption speed of mGO-PAO for U(VI) was found to be 18 times faster in the ultrasonic field than in the shaking mode, and the adsorption equilibrium, to be reached within 2 min. When the U(VI) concentration was 10 mg/L, the temperature, 298 K, and pH, 6.0, the removal rate of U(VI) reached 98.24% with high selectivity. The adsorption kinetics and isotherm data were well described by the pseudo-second-order and Langmuir models, respectively. The thermodynamic parameters suggested that the adsorption of U(VI) was a typical spontaneous and endothermic process. XPS analysis suggested that the mGO-PAO bound the U(VI) through the η2-N,O binding mode. Moreover, the mGO-PAO exhibits excellent adsorption performance in actual radioactive wastewater with an assist of ultrasound. This work provides a new approach for highly effective extraction of U(VI) from the actual radioactive wastewater. © 2018 American Chemical Society.
语种：
英文
展开
Bioremediation of effluent from a uranium mill tailings repository in South China by Azolla-Anabaena
作者：
Huang Xinwei;Wang Yongdong;Hu Nan;Sha Yinhua;Ding Dexin*
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年317(2):739-746 ISSN：0236-5731
通讯作者：
Ding Dexin
作者机构：
[Wang Yongdong; Hu Nan; Ding Dexin; Sha Yinhua; Huang Xinwei] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Wang Yongdong; Hu Nan; Ding Dexin; Sha Yinhua; Huang Xinwei] Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.
通讯机构：
[Ding Dexin] U;[Ding Dexin] H;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Peoples R China.
关键词：
Azolla–Anabaena;Effluent;Uranium mill tailings repository;Uranium;Bioremediation
摘要：
Hydroponic experiments were conducted on the removal of uranium, heavy metals and nutrients from the effluent of a uranium mill tailings repository in South China by Azolla–Anabaena. The plant–microbe symbiont was kept in the effluent for 30 days, and it was found that U, Fe, Mn, Cu, Zn, Pb, Cd, total phosphorus (TP), total nitrogen (TN) and SO4 2− reduced by 87.6, 99.1, 98.8, 88.2, 91, 78.3, 77.5, 93.4, 98.7 and 76.7%, respectively. Specifically, the concentration of uranium reduced to 0.039 mg L−1, which is below the limits of contaminants by the Department of Environmental Protection of China. The concentration of Fe, Cu, Zn, Pb, TP and TN in the effluent reached the quality standard for drinking water. The results showed that Azolla–Anabaena can be used for the bioremediation of the effluent from the uranium mill tailings repository. © 2018, Akadémiai Kiadó, Budapest, Hungary.
语种：
英文
展开
Damage evolution and deformation behaviour of dry and saturated sandstones: Insights gleaned from optical measurements
作者：
Wasantha, P. L. P.* ;Ranjit, P. G.;Permata, G.;Bing, D.
期刊：
Measurement ,2018年130:8-17 ISSN：0263-2241
通讯作者：
Wasantha, P. L. P.
作者机构：
[Wasantha, P. L. P.] Victoria Univ, Coll Engn & Sci, Melbourne, Vic, Australia.;[Ranjit, P. G.; Permata, G.] Monash Univ, Dept Civil Engn, Deep Earth Energy Lab, Clayton, Vic 3800, Australia.;[Bing, D.] Univ South China, Nucl Resources Engn Coll, Heng Yang 421001, Peoples R China.
通讯机构：
[Wasantha, P. L. P.] V;Victoria Univ, Coll Engn & Sci, Melbourne, Vic, Australia.
关键词：
Sandstone mechanical behaviour;Microscopic properties;Damage evolution
摘要：
Microscopic properties have a marked influence on the macroscopic mechanical response of sandstones. Improved understanding of the mechanical behaviour of these rocks caused by their microscopic properties is imperative for the successful design of rock structures. Here we experimentally investigate the damage evolution and deformation behaviour of three types of sandstones from Australia with contrasting petrographic properties under dry and saturated conditions with the aid of an optical strain and deformation measurement system (ARAMIS camera). More accurate and representative strain measurements are obtained using ARAMIS camera images compared to conventional strain measurement techniques. The results revealed that the quartz content of sandstone alone is not indicative of its strength, as the sandstone with the highest quartz content showed the lowest strength and this was attributed to the superior influence of other microscopic properties, such as grain size and porosity. However, the quartz content displayed a significant influence on the water-weakening behaviour of the sandstones, where the sandstone with the greatest quartz content was least affected by saturation and the sandstones with considerable clay mineral content showed greater weakening due to water. It was also found that some clay minerals are susceptible to swelling in the presence of water, and this can increase the initial crack volume and affect deformation characteristics. ARAMIS camera images clearly illustrated a more brittle behaviour by the sandstone with the greatest quartz content and notable early deformation by the sandstones with greater clay mineral content. Moreover, it was found that the overall deformation of sandstones was influenced by the swelling capacity of the constituent clay minerals, in addition to their composition by percentage.
语种：
英文
展开
Study on the influence of temperature and humidity on radon exhalation from a radon-containing solution
作者：
Zhou, Ju;Ding, Dexin* ;Ye, Jiang
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年318(2):1099-1107 ISSN：0236-5731
通讯作者：
Ding, Dexin
作者机构：
[Zhou, Ju] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Ding, Dexin; Zhou, Ju] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Ye, Jiang] Univ South China, Sch Mech Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, Dexin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Radon-containing solution;Radon exhalation rate;Transfer radon velocity;Temperature;Humidity
摘要：
The radon exhalation rate and transfer radon velocity between liquid and gas under different temperature and humidity conditions are investigated. The fitting formulas of radon exhalation rate and temperature and humidity are exponential functions, and each exponent is a 2nd-order polynomial. The fitting formula of transfer radon velocity and temperature is Boltzmann function, and the velocity tends to be stable gradually at 25 °C. The fitting formula of transfer radon velocity and humidity is exponential function whose exponent is a 2nd order polynomial, and the velocity increases at first when the humidity was 0.75, then decreases with increasing humidity.
语种：
英文
展开
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
展开
Removal of Cr(VI) From Electroplating Industry Effluent via Electrochemical Reduction
作者：
Li, Shiyou;Hu, Zhongqing;Xie, Shuibo;Liu, Haiyan;Liu, Jinxiang*
期刊：
International Journal of Electrochemical Science ,2018年13(1):655-663 ISSN：1452-3981
通讯作者：
Liu, Jinxiang
作者机构：
[Hu, Zhongqing; Xie, Shuibo; Liu, Haiyan; Liu, Jinxiang; Li, Shiyou] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Tec, Hengyang 421001, Hunan, Peoples R China.;[Xie, Shuibo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Liu, Jinxiang] U;Univ South China, Hunan Prov Key Lab Pollut Control & Resources Tec, Hengyang 421001, Hunan, Peoples R China.
关键词：
Pollution management;Electrode configuration;Industry Effluent;Electrochemical reduction;Cr(VI) removal
摘要：
In the present work, an electrochemical reduction process with iron and titanium electrodes was investigated for hexavalent chromium (Cr(VI)) removal. The removal of Cr(VI) and its resulting species was investigated by measuring the efficiency of the electrochemical reduction treatment. For the Cr(VI) removal, a lower performance was found for the titanium electrode than the iron electrode. Therefore, the resulting Cr(VI) reduction, which occurred through electrochemical reduction using iron electrodes, was chemical reduction by the anodically generated Fe(II). Furthermore, the resulting Cr(III) was efficiently precipitated as Cr(OH)3 and was rapidly removed from solution. © 2018 The Authors.
语种：
英文
展开
Prediction model of uranium concentration for in-situ leaching pregnant solution based on uranium chemical fractions of ores
作者：
Li, Chunguang;Tan, Kaixuan* ;Liu, Zhenzhong;Xia, Liangshu;Tan, Wanyu;...
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年318(2):1379-1387 ISSN：0236-5731
通讯作者：
Tan, Kaixuan
作者机构：
[Chen, Liang; Tan, Wanyu; Tan, Kaixuan; Li, Chunguang] Univ South China, Sch Nucl Resources Engn, 28 Changsheng West Rd, Hengyang 421001, Peoples R China.;[Li, Chunguang] RMIT Univ, Sch Engn, 124 La Trobe St, Melbourne, Vic 3001, Australia.;[Liu, Zhenzhong] Univ South China, Sch Environm Protect & Safety Engn, 28 Changsheng West Rd, Hengyang 421001, Peoples R China.;[Xia, Liangshu] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Tan, Kaixuan] U;Univ South China, Sch Nucl Resources Engn, 28 Changsheng West Rd, Hengyang 421001, Peoples R China.
关键词：
In-situ leaching;Uranium concentration;Chemical fractions;Prediction model
摘要：
Based on the uranium chemical fractions, combined with laboratory experiments and field monitoring data, a prediction model of uranium concentration for in situ leaching pregnant solution was established. It was demonstrated that the kinetics of in situ leaching of uranium is affected by four chemical fractions from exchangeable to oxidizable after the acidification stage, meanwhile the variation of uranium concentration with time displays two trends as high → low and low → high → low, moreover, it is basically consistent with the fourth-order polynomial relationship. The prediction model equation is y i,x = a i x 4 + b i x 3 + c i x 2 + d i x + e i , among which the parameters can be obtained by the regression of uranium chemical fractions of ores. © 2018, Akadémiai Kiadó, Budapest, Hungary.
语种：
英文
展开
Novel graphene oxide/bentonite composite for uranium(VI) adsorption from aqueous solution
作者：
Liu, Hongjuan* ;Xie, Shuibo* ;Liao, Ju;Yan, Tianrun;Liu, Yingjiu;...
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年317(3):1349-1360 ISSN：0236-5731
通讯作者：
Liu, Hongjuan;Xie, Shuibo
作者机构：
[Liu, Hongjuan; Liao, Ju; Yan, Tianrun] Univ South China, Inst Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Xie, Shuibo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Xie, Shuibo; Liu, Yingjiu] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reu, Hengyang 421001, Peoples R China.;[Tang, Xinhai] Shanghai Jiao Tong Univ, Sch Mech Engn, Shanghai 200240, Peoples R China.
通讯机构：
[Liu, Hongjuan; Xie, Shuibo] U;Univ South China, Inst Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reu, Hengyang 421001, Peoples R China.
关键词：
Adsorption;U(VI);Graphene oxide;Bentonite
摘要：
A novel graphene oxide/bentonite composite (GO/bentonite) was synthesized and then characterized through powder X-ray diffraction, fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and energy dispersive spectroscopy. Adsorption achieved equilibrium within 10 min. Moreover, U(VI) adsorption on GO/bentonite was highly dependent on solution pH and independent of ionic strength. These characteristics suggested that inner-sphere surface complexes of U(VI) formed on GO/bentonite. The adsorption of U(VI) from aqueous solution on GO/bentonite was fitted to the pseudo-second-order and Freundlich isotherm models. The maximum sorption capacity of GO/bentonite was 234.19 mg g−1 under neutral pH at 303 K. GO/bentonite is a potentially powerful adsorbent for the efficient removal of U(VI) from aqueous solutions. © 2018, Akadémiai Kiadó, Budapest, Hungary.
语种：
英文
展开
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
展开
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
展开
Preparation of 4-sulfonylcalix[6]arene modified Fe3O4 as adsorbent for adsorption of U(VI) from aqueous solution
作者：
Liao, Qi;Li, Le* ;Yuan, Yali* ;Cheng, Bin;Lu, Wei;...
期刊：
Journal of Radioanalytical and Nuclear Chemistry ,2018年315(2):251-261 ISSN：0236-5731
通讯作者：
Li, Le;Yuan, Yali
作者机构：
[Cheng, Bin; Lu, Wei; Li, Le; Liao, Qi] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Hou, Shaoyan; Yuan, Yali; Liao, Qi] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;[Cheng, Bin; Lu, Wei; Li, Le] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
通讯机构：
[Li, Le; Yuan, Yali] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Peoples R China.;Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
关键词：
4-Sulfonylcalix[6]arene;Fe3O4;Co-precipitation;Adsorption;Uranium
摘要：
The 4-sulfonylcalix[6]arene modified Fe 3 O 4 (MFS) was characterized by FT-IR, SEM, VSM, TGA, etc., which showed that its saturation magnetization was 64.99 emu g −1 with the particle size 10–40 nm. The maximum adsorption efficiency by MFS for 2.5 mg L −1 U(VI) solution amounted to 94.39%, which was higher than that by Fe 3 O 4 (65.22%) under its optimum adsorption conditions. The adsorption of MFS and Fe 3 O 4 were both followed the pseudo-second order model and the Langmuir isotherm model. The Gibbs free energy change and enthalpy change revealed that the adsorption of U(VI) by MFS was a spontaneous and endothermic process. © 2017, Akadémiai Kiadó, Budapest, Hungary.
语种：
英文
展开
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
展开
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
展开
