Mechanism of recombinant bacteria adsorb UO22+ under culture condition
作者：
Shu, Yangzhen;Li, Shanshan;Xie, Jingxi;Guo, Kexin;Cheng, Conghui;...
期刊：
Enzyme and Microbial Technology ,2021年151:109920 ISSN：0141-0229
通讯作者：
Peng, Guowen(pgwnh78@163.com);Xiao, Fangzhu(xfzhunh@163.com)
作者机构：
[Shu, Yangzhen; Peng, Guowen] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Xiao, Fangzhu; Cheng, Conghui; Guo, Kexin; Chen, Luoyao; Li, Shanshan] Univ South China, Sch Publ Hlth, Hengyang 421001, Hunan, Peoples R China.;[Xie, Jingxi; Peng, Guowen] Univ South China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Peng, G.; Xiao, F.] S;School of Environmental Protection and Safety Engineering of University of South ChinaChina;School of Public Health, China
关键词：
Biosorption;Mechanism;Uranium
摘要：
Research on the ability and mechanism of genetically recombinant E. coli DH5α containing DSR A gene to enrich uranium under culture conditions provides a theoretical basis for the application of the bacteria in the treatment of uranium pollution. By exploring the influence of factors such as the initial concentration of uranium, culture time, and inoculation amount on the characteristics of uranium enrichment in genetically recombinant E. coli, using FTIR, SEM-EDS, XPS and XRD explore the mechanism of uranium-enriched bacteria. The results showed that when initial UO22+ concentration reach 600 mg/L, E. Coli D1 could not survived, indicated that the maximum tolerance concentration is lower than 600 mg/L. While concentration between 0∼500 mg/L, strains D1 can grow normally and has the ability to enrich uranium. In the prime stage, strains D1 resist toxics through release inorganic phosphates to precipitate UO22+ on cell wall, after 96 h, most UO22+ were transferred into cytoplasm and metabolized into U(IV) which is less toxic. In the metabolize process, all groups involved in metabolizing UO22+, especially protein contain groups like hydroxyl, amine and carboxyl paly a huge role. It shows that within a certain concentration rage, strains D1 has a good enrichment effect on uranium under culture conditions. © 2021 Elsevier Inc.
语种：
英文
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Developmental toxicity and apoptosis in zebrafish embryos induced by low-dose -ray irradiation
作者：
Zhao, Weichao;Hu, Nan;Ding, Dexin* ;Long, Dingxin;Li, Sheng;...
期刊：
Environmental Science and Pollution Research ,2019年26(4):3869-3881 ISSN：0944-1344
通讯作者：
Ding, Dexin
作者机构：
[Zhao, Weichao] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Ding, Dexin; Zhang, Hui; Li, Sheng; Li, Guangyue; Hu, Nan] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Long, Dingxin; Zhao, Weichao] 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：
Apoptosis;Developmental toxicity;Low-dose gamma-ray irradiation;Signaling pathway;Zebrafish embryos
摘要：
In this paper, the developmental toxicity and apoptosis in zebrafish (Danio rerio) embryos induced by 0.01, 0.05, and 0.10-Gy gamma-ray irradiation were investigated and verified by single cell gel electrophoresis, acridine orange staining, flow cytometry, transmission electron microscopy, digital gene expression sequencing, and Western blot analysis. DNA damage, deformity rates, and apoptosis of zebrafish embryos were found to increase significantly with the increase of irradiation dose, and survival and hatching rates significantly decreased when the irradiation dose exceeds 0.10 and 0.05 Gy, respectively. Exposure to 0.10-Gy gamma-ray irradiation resulted in the swelling of cell mitochondria of zebrafish embryos and changes in their intracellular vacuoles. mRNA and protein expression levels of Shh (sonic hedgehog 19 KDa) and Smo (smoothened 86 KDa) of Hh signaling pathway associated with the development of early embryos significantly increased with the increase of irradiation dose. Expression of the AKT (56 KDa) and PiK3r3 (55 KDa) genes, which are anti-apoptotic and involved with the PI3K/Akt signaling pathway, significantly decreased, while expression of the bada gene, which is pro-apoptotic, significantly increased. The results show that gamma-ray irradiations of 0.01 and 0.05 Gy can induce developmental toxicity and apoptosis in zebrafish embryos via Hh and PI3K/Akt signaling pathways, respectively.
语种：
英文
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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. (C) 2018 Elsevier Ltd. All rights reserved.
语种：
英文
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A universal laboratory method for determining physical parameters of radon migration in dry granulated porous media
作者：
Ye, Yong-jun* ;Zhang, Yun-feng;Dai, Xin-tao;Ding, De-xin
期刊：
Journal of Environmental Radioactivity ,2017年177:135-141 ISSN：0265-931X
通讯作者：
Ye, Yong-jun
作者机构：
[Ye, Yong-jun; Ding, De-xin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Dai, Xin-tao; Ye, Yong-jun; Zhang, Yun-feng] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ye, Yong-jun] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Diffusion;Mechanical permeability;Ores;Particle size;Porosity;Porous materials;Determining method;Experimental devices;Experimental errors;Laboratory methods;Mass conservation law;Physical parameters;Radon diffusion coefficient;Radon production rate;Radon;radon;uranium;radon;soil pollutant;design;diffusion;experimental apparatus;granular medium;laboratory method;permeability;physical property;porosity;porous medium;radioactive decay;radionuclide migration;radon;sandy soil;uranium;Article;diffusion coefficient;environmental exposure;laboratory technique;mine tailings;permeability;physical parameters;porosity;radiation measurement;radioactive pollution;rock;sampling;sand;sandy soil;waste;analysis;diffusion;particle size;procedures;radiation monitoring;soil pollutant;standards;Diffusion;Particle Size;Porosity;Radiation Monitoring;Radon;Soil Pollutants, Radioactive
摘要：
The particle size and heaped methods of exhalation media have important effects on physical parameters, such as the free radon production rate, porosity, permeability, and radon diffusion coefficient. However, existing methods for determining those parameters are too complex, and time-consuming. In this study, a novel, systematic determining method was proposed based on nuclide decay, radon diffusion migration theory, and the mass conservation law, and an associated experimental device was designed and manufactured. The parameters of uranium ore heap and sandy soil of radon diffusion coefficient (D), free radon production rate (α), media permeability (k), and porosity (ε) were obtained. At the same time, the practicality of the novel determining method was improved over other methods, with the results showing that accuracy was within the acceptable range of experimental error. This novel method will be of significance for the study of radon migration and exhalation in granulated porous media. © 2017 Elsevier Ltd
语种：
英文
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Predictive analysis of shaft station radon concentrations in underground uranium mine: A case study
作者：
Zhao, Guoyan;Hong, Changshou* ;Li, Xiangyang;Lin, Chunping;Hu, Penghua
期刊：
Journal of Environmental Radioactivity ,2016年158-159:129-137 ISSN：0265-931X
通讯作者：
Hong, Changshou
作者机构：
[Lin, Chunping; Zhao, Guoyan; Hong, Changshou] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.;[Li, Xiangyang] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Hu, Penghua] China Natl Nucl Corp, Beijing Res Inst Chem Engn & Met, Beijing 101149, Peoples R China.
通讯机构：
[Hong, Changshou] C;Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.
关键词：
Intelligent systems;Mining;Monte Carlo methods;Queueing theory;Radon;Uranium;Uranium mines;Average waiting-time;Mathematical derivation;Predictive analysis;Predictive modeling;Queuing theory;Radiation safety;Radon concentrations;Shaft station;Mine shafts;radon;air pollutant;radon;uranium;concentration (composition);model validation;Monte Carlo analysis;numerical model;radon;shaft;uranium;Article;concentration (parameters);mathematical analysis;Monte Carlo method;predictive value;radiation safety;simulation;theoretical model;uranium mine;air pollutant;analysis;computer simulation;mining;radiation monitoring;theoretical model;China;Air Pollutants, Radioactive;Computer Simulation;Mining;Models, Theoretical;Monte Carlo Method;Radiation Monitoring;Radon;Uranium
摘要：
This paper presented a method for predicting shaft station radon concentrations in a uranium mine of China through theoretical analysis, mathematical derivation and Monte-Carlo simulation. Based upon the queuing model for tramcars, the average waiting time of tramcars and average number of waiting tramcars were determined, which were further used in developing the predictive model for calculating shaft station radon concentrations. The results exhibit that the extent of variation of shaft station radon concentration in the case study mine is not significantly affected by the queuing process of tramcars, and is always within the allowable limit of 200 Bq m-3. Thus, the empirical limit of 100,000 T annual ore-hoisting yields has no value in ensuring radiation safety for this mine. Moreover, the developed model has been validated and proved useful in assessing shaft station radon levels for any uranium mine with similar situations. © 2016 Elsevier Ltd.
语种：
英文
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Modeling and experimental examination of water level effects on radon exhalation from fragmented uranium ore
作者：
Ye, Yong-jun* ;Dai, Xin-tao;Ding, De-xin;Zhao, Ya-li
期刊：
Journal of Environmental Radioactivity ,2016年165:219-226 ISSN：0265-931X
通讯作者：
Ye, Yong-jun
作者机构：
[Ye, Yong-jun; Ding, De-xin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Dai, Xin-tao; Ye, Yong-jun; Zhao, Ya-li] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ye, Yong-jun] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Air;Interface states;Models;Phase interfaces;Radon;Uranium;Water levels;Air water interfaces;Experimental apparatus;Experimental examination;One dimensional steady state;Radon concentrations;Radon exhalation rate;Steady-state condition;Uranium ore;Ores;radon;uranium;water;pollutant;radon;uranium;air-water interaction;concentration (composition);exhalative deposit;experimental study;numerical model;one-dimensional modeling;ore deposit;pollutant transport;radon;uranium;water level;air;Article;calculation;diffusion;exhalation;mathematical model;steady state;analysis;chemical model;pollutant;procedures;radiation monitoring;Models, Chemical;Radiation Monitoring;Radioactive Pollutants;Radon;Uranium
摘要：
In this study, a one-dimensional steady-state mathematical model of radon transport in fragmented uranium ore was established according to Fick's law and radon transfer theory in an air-water interface. The model was utilized to obtain an analytical solution for radon concentration in the air-water, two-phase system under steady state conditions, as well as a corresponding radon exhalation rate calculation formula. We also designed a one-dimensional experimental apparatus for simulating radon diffusion migration in the uranium ore with various water levels to verify the mathematical model. The predicted results were in close agreement with the measured results, suggesting that the proposed model can be readily used to determine radon concentrations and exhalation rates in fragmented uranium ore with varying water levels. © 2016
语种：
英文
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A New Method for Determining the Absorbed Dose in a Radiation Field by Using a Thiamine Hydrochloride Aqueous Solution
作者：
Li, Ying;Lv, Changyin* ;Zhao, Ying;Sun, Qiang;Li, Yunjing
期刊：
Analytical Sciences ,2013年29(12):1189-1194 ISSN：0910-6340
通讯作者：
Lv, Changyin
作者机构：
[Li, Ying; Lv, Changyin; Li, Yunjing; Sun, Qiang; Zhao, Ying] Univ South China, Inst Environm & Radiat Med, Sch Publ Hlth, Hengyang 421001, Hunan, Peoples R China.;[Lv, Changyin] Univ South China, Inst Environm & Radiat Med, Sch Publ Hlth, Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Lv, Changyin] U;Univ South China, Inst Environm & Radiat Med, Sch Publ Hlth, Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
关键词：
Thiamine hydrochloride;radiation dosimeter;high-performance liquid chromatography (HPLC);mass spectrum;1H-NMR spectrum
摘要：
This research investigated the ionizing radiation effect on thiamine hydrochloride (TH) and its usability as an irradiation dosimeter. The fundamental principle is to determine the concentration variations of TH solutions with high-performance liquid chromatography (HPLC) after exposing to γ-rays. The decreasing peak area of TH in the HPLC chromatogram forms a linear relationship with the rising radiation dose. We investigated the characteristics and suitable application range of the TH as a new radiation dosimeter. The influence factors and mechanism of the reaction induced by radiation were also discussed. According to the correlation between the concentration and the radiation dose, 0.3 g/L of a TH solution is suitable for the 0.1 - 10 kGy dose range, and 2 g/L is appropriate for 0.1 - 20 kGy. The easy availability and the simple, but stable, chemical structure of thiamine makes it a potential candidate for radiation dose research. Also, the preparation proceeding for sampling is easy, and the result can be automatic monitored by liquid chromatography. ©The Japan Society for Analytical Chemistry.
语种：
英文
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硫酸盐还原菌还原U(Ⅵ)的影响因素与机制
作者：
谢水波;王水云;张浩江;刘迎九;王劲松
期刊：
环境科学 ,2009年30(7):1962-1967 ISSN：0250-3301
作者机构：
[谢水波; 王水云; 刘迎九] Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang 421001, China;[张浩江] College of Civil Engineering, Hunan University, Changsha 410012, China;[王劲松] Institute of Environment Protection, University of South China, Hengyang 421001, China
关键词：
铀;抑制机制
摘要：
在厌氧环境下,改变温度、U(Ⅵ)的初始浓度、pH值、共存离子等因素,进行硫酸盐还原菌(SRB)还原U(Ⅵ)试验,以了解其特性.结果表明,SRB的最佳还原条件为温度35℃、pH值7.0、U(Ⅵ)初始浓度25 mg·L~(-1).SRB的最大还原能力为179.1mg·g~(-1).共存离子M0(Ⅵ)或Ca~(2+)初始浓度小于或等于5 g·L~(-1)时,对SRB还原U(Ⅵ)影响不大;但当其浓度达到20 g·L~(-1)时,它们对SRB还原U(Ⅵ)均具有很强的抑制作用.Mo(Ⅵ)对SRB的抑制主要是生理抑制,Ca~(2+)是通过和U(Ⅵ)形成稳定的Ca-UO_2-CO_3络合物竞争抑制.试验结果还表明,Ca~(2+)浓度低于5 g·L~(-1)时未出现停滞期,但其浓度超过20 g·L~(-1)时出现了1 d的停滞期.
语种：
中文
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正畸治疗骨性Ⅲ类错(牙合)对下颌平面角小的成年女性患者颞下颌关节的影响
作者：
蒋复量;张帅;李向阳;洪昌寿;黎明;...
期刊：
中华口腔医学杂志 ,2007年42(8):471-474 ISSN：1002-0098
通讯作者：
Wang, C.L.
作者机构：
[蒋复量; 李向阳; 张帅; 洪昌寿; 黎明; 杨文超] 南华大学环境与安全工程学院;[蒋复量; 李向阳] 湖南省铀尾矿库退役治理技术工程研究中心;[蒋复量; 李向阳] 铀矿冶放射性控制技术湖南省工程研究中心
关键词：
错(牙合),安氏Ⅲ类;正畸学,矫正;颞下颌关节
摘要：
目的分析正畸矫治前后成年女性骨性Ⅲ类错(牙合)低角患者颞下颌关节的变化,探讨非手术正畸治疗对成年骨性Ⅲ类错(牙合)低角患者颞下颌关节的影响。方法选取16例成年女性骨性Ⅲ类错(牙合)低角患者,18～23岁,采用 OPA-K 滑动直丝弓技术矫治,矫治前后拍摄双侧闭口矫正许勒位片和头颅侧位 X 线片,进行颞下颌关节间隙测量和头影测量分析。对矫治前后的测量数据进行配对 t检验。结果与矫治前相比,矫治后关节前间隙线距和面积分别增加0.27 mm(P<0.001)、0.70 mm~2(P<0.01),关节后间隙线距和面积分别减小0.24 mm、0.67 mm~2(P<0.001),线性百分比由22.13%减少为9.64%(P<0.001),关节后前间隙面积之比由1.56减小为1.19(P<0.01),关节前间隙与关节后间隙趋于相等。头影测量发现,与矫治前相比,矫治后点 Co、Ar、Go 及 Pg 相对前颅底均明显后移(P<0.05)。结论成年骨性Ⅲ类错(牙合)低角患者非手术矫治后髁突由下前位向后向上移至中位,关节结构趋于协调和稳定,有利于颞下颌关节紊乱病症状的缓解。
语种：
中文
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