Adsorption of U(VI) ions from aqueous solution using nanogoethite powder
作者:
Zhang, Lijiang;Zhang, Xiaowen* ;Lu, Qian;Wu, Xiaoyan;Jiang, Tianjiao;...
期刊:
Adsorption Science & Technology ,2019年37(1-2):113-126 ISSN:0263-6174
通讯作者:
Zhang, Xiaowen
作者机构:
[Lu, Qian; Peng, Ying; Zhang, Lijiang; Zhang, Xiaowen; Jiang, Tianjiao; Wu, Xiaoyan; Mi, Li] Univ South China, Sch Resources Environm & Safety Engn, Hengyang, Peoples R China.;[Zhang, Xiaowen; Mi, Li] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang, Peoples R China.;[Zhang, Xiaowen] Univ South China, Hengyang 421001, Hunan, Peoples R China.
通讯机构:
[Zhang, Xiaowen] U;Univ South China, Hengyang 421001, Hunan, Peoples R China.
关键词:
Uranium;chemical precipitation synthesis;nanogoethite;adsorption;iron oxide
摘要:
Goethite is a stable and widespread mineral present in soil with many uses, and it affects the transportation and immobilization of heavy metals in solution. Nanogoethite was synthesized by a chemical precipitation method and used to batch adsorb U(VI) in solution. Adsorption experiments were used to understand the role of nanogoethite in controlling the U(VI) adsorption behavior in soil. The morphology and the crystallinity of nanogoethite were characterized by scanning electron microscopy and wide-angle X-ray powder diffractometry, respectively. The results showed that the crystallinity of nanogoethite after the adsorption of uranium did not change, but small particles appeared on the surface of the scales. The surface area was determined from N 2 adsorption–desorption experiments using the Brunauer–Emmett–Teller to be 81.86 m 2 /g. The effects of factors such as the contact time, pH, adsorbent dosage, and the initial concentration of uranium on the adsorption of U(VI) were investigated. The experimental results showed that nanogoethite removed over 85% of the U(VI) in an aqueous 5.0 mg/L U(VI) solution at pH 4.0 and at 298 K. The pseudo-second-order model was used to simulate the adsorption process. The results show that chemisorption plays a major role in the adsorption process. The results of this study suggest that nanogoethite may play a significant role in controlling the migration and transfer of U(VI) in the soil, thus controlling the presence of U(VI) in soil. © The Author(s) 2019.
语种:
英文
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Behavior of Piles Subjected to Surcharge Loading in Deep Soft Soils: Field Tests
作者:
Li, Hong-quan;Wei, Li-min;Feng, Sheng-yang;Chen, Zhi
期刊:
Geotechnical and Geological Engineering ,2019年37(5):4019-4029 ISSN:0960-3182
通讯作者:
Feng, Sheng-yang(14100044@usc.edu.cn)
作者机构:
[Feng, Sheng-yang; Chen, Zhi] School of Environment and Safety Engineering, University of South China, Hengyang;Hunan, China;[Li, Hong-quan; Wei, Li-min] School of Civil Engineering, Central South University, Changsha;[Li, Hong-quan; Wei, Li-min; Feng, Sheng-yang; Chen, Zhi] Hunan, China
通讯机构:
[Sheng-yang Feng] S;School of Environment and Safety Engineering, University of South China, Hengyang, Hunan, China
关键词:
Deep soft soil;Field tests;Pile;Surcharge loading
摘要:
A series of field tests were conducted to examine the behavior of pile foundation subjected to adjacent surcharge loading in deep soft soils. The emphasis was on the pile deflection, bending moment, soil horizontal displacement and lateral earth pressure acting on the piles under different surcharge loading conditions. It was found that among the surcharge loading distance, intensity and width, the surcharge loading distance was the most significant factor affecting the adjacent piles in deep soft soils. The springback process of piles subjected to adjacent surcharge loading after unloading was a slow process changing with time. The mean lateral earth pressure on the pile facing the surcharge loading is slightly larger than that opposite to the surcharge loading. The pile bending moment and mean lateral earth pressure acting on the pile decrease with time due to the consolidation process of soft soil. 3D finite element model in ABAQUS is established to study the influence of consolidation process of soft soil on piles subject to adjacent surcharge loading. © 2019, Springer Nature Switzerland AG.
语种:
英文
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中厚倾斜矿体导流放矿实验研究 <&wdkj&>Experimental study on diversion drawing of inclined medium-thick ore body
作者:
陶干强;杨剑锋;任凤玉;张秀凤
期刊:
采矿与安全工程学报 ,2019年36(1):59-64 ISSN:1673-3363
通讯作者:
Ren, Fengyu(happyrst@163.com)
作者机构:
[陶干强; 杨剑锋; 张秀凤] School of Resource & Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;[任凤玉] College of Resources and Civil Engineering, Northeastern University, Shenyang;Liaoning
通讯机构:
[Ren, F.] C;College of Resources and Civil Engineering, Northeastern University, Shenyang, Liaoning, China
关键词:
中厚倾斜矿体;导流放矿;正交设计法;回收率;贫化率;回贫差
摘要:
为了降低中厚倾斜矿体开采过程中的损失贫化,改革传统的矿岩接触形式,采用新型导流结构将覆岩与爆破矿石隔离。采用正交设计方法确定了9组实验方案,开展了斜壁导流放矿物理模拟实验。实验结果表明,与传统放矿方式相比,新型导流放矿能明显改善矿石损失贫化指标;采用极差分析法分析了矿体厚度、矿体倾角、分段高度三因素对矿石回收率、贫化率、回贫差的敏感性,得知矿体厚度对矿石回收率、贫化率的影响最为显著,分段高度对矿石回贫差的影响最为显著;作出了各因素对放矿指标影响的直观分析图,分析了各因素对放矿指标的影响规律。本研究为中厚倾斜矿体采矿技术经济评价和分段崩落法结构参数优化设计提供了依据。
语种:
中文
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Understanding the solid phase chemical fractionation of uranium in soil profile near a hydrometallurgical factory
作者:
Yang, Sheng;Zhang, Xiaowen* ;Wu, Xiaoyan;Li, Mi;Zhang, Lijiang;...
期刊:
Chemosphere ,2019年236(Dec.):124392 ISSN:0045-6535
通讯作者:
Zhang, Xiaowen
作者机构:
[Li, Mi; Yang, Sheng; Peng, Ying; Zhang, Lijiang; Huang, Qianwen; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan] Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构:
[Zhang, Xiaowen] U;Univ South China, Sch Resource & Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词:
Adsorption-migration;Sequential extraction;Soil profile;Spatial distribution;U
摘要:
Uranium (U) contamination of soil has become a major concern with respect to its toxicity, accumulation in the food chain, and persistence in the environment. Anthropogenic activities like mining and processing of U ores has become pressing issues throughout the world. The aim of the work is to understand the chemical fractionation of U in polluted soil and the mechanism involved. U-free soils samples of eluvial (E), illuvial (B), and parent-material (C) horizons from a hydrometallurgical factory area were used. The experimental results showed that the U adsorption capacity decreased with depth, and its mobility in the upper soil is better than the lower. It was closely related to distribution coefficient (Kd), pH, organic-matter (OM), and carbonate content of soil horizons. The chemical fractionation of U was studied using the BCR sequential extraction scheme for soils after saturated adsorption. It was noted that the U reducible and oxidizable fraction in the E and B horizons can vertically transfer to the C horizon and occurs a significant rearrangement of U in different horizons. BET, SEM, XRD, and FT-IR analyses showed that different U distribution and migration in soil profile is mainly affected by specific surface area, soil particle size, mineral composition, and active groups. The XPS data further indicated that U (VI) is gradually converted to U (IV) with decreased depth and fixed in deeper soil becoming insoluble and immobile. It is the first step to investigate potential migration and plan U mining and milling area long-term management. © 2019
语种:
英文
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Physics-oriented optimization strategy for the energy lookup algorithm in continuous energy Monte Carlo neutron transport simulation
作者:
Chen, Zhenping;Xie, Jinsen;Guo, Qian;Xie, Qin;Liu, Zijing;...
期刊:
Computer Physics Communications ,2019年234:146-158 ISSN:0010-4655
通讯作者:
Yu, Tao
作者机构:
[Liu, Zijing; Xie, Qin; Chen, Zhenping; Zeng, Wenjie; Xie, Jinsen; Zhao, Pengcheng; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Xie, Chao; Guo, Qian] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构:
[Yu, Tao] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词:
Continuous energy;Energy lookup;Monte Carlo;Neutron transport;Optimization
摘要:
The continuous energy Monte Carlo method is a most high-fidelity and high-resolution method for neutron transport simulations in reactor physics with minimal approximations. However, one of the major disadvantages is that it is very time-consuming and computational-intensive for large scale whole-core simulations, especially for coupling with depletion analysis for realistic reactors. Some recent researches indicate that one of the principle performance bottlenecks for the problem lies in the energy lookup algorithm during the calculation of energy-dependent material cross sections. Therefore, two physics-oriented optimization strategies, based on making use of the physical characteristics of neutron transport behaviors, are developed to optimize the run-time performance of the algorithm for accelerating the energy lookup without any loss in precision and accuracy. The first optimization strategy is called Neighbored Material Cascade Grid (NMCG) which is a hybrid approach utilizing the key features of the cascade grid and double indexing method. The second optimization strategy is called Adaptive Optimal Logarithmic Grid (AOLG) which is a variation of the conventional logarithmic energy grid method utilizing the advantages of energy hash tables. The strategies are incorporated into a continuous energy Monte Carlo neutron transport code and tested on realistic whole-core reactor systems. The computational performance as measured by memory usage, elapsed runtime and overall speedup, associated with each of the optimization strategies are demonstrated in the whole-core Monte Carlo simulations. Depending on the complexity of the models, the number of nuclides in the material compositions and the utilization of different optimization strategies, overall speedup ratios of 1.2-1.7, relative to the conventional binary lookup algorithm, are routinely observed. Furthermore, the numerical results indicate that the run-time performance of the new physics-oriented optimization strategies performs a bit better than that of conventional optimization methods with existing approaches. © 2018 Elsevier B.V.
语种:
英文
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固态图像传感器的电离辐射响应均匀性
作者:
徐守龙;邹树梁;韩永超;刘明忠;曲延涛;...
期刊:
光学学报 ,2019年39(7):391-399 ISSN:0253-2239
作者机构:
[徐守龙; 邹树梁] School of Resource Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;Department of Engineering Physics, Tsinghua University, Beijing;100084, China
关键词:
传感器;电离辐射响应;非均匀性;γ射线;像素
摘要:
研究并对比了6类电荷耦合器件和互补金属氧化物半导体图像传感器的辐射响应均匀性。设计辐射实验,对像素阵列中响应信号在不同统计区域内的像素值增量平均值和非均匀度进行分析与讨论,重点研究了各类固态图像传感器像素阵列全局、区域和代表像元的辐射响应均匀性。实验结果表明:在稳态γ射线辐射场辐照条件下,帧图像中的响应信号增量并非固定值;像素阵列各区域内响应信号的均匀性不因辐照剂量率的变化而变化,对于相同的图像传感器,辐射在任意帧图像中产生辐射响应信号的分布与像素阵列中任意像素在多帧图像中出现辐射响应的分布相同,但由于传感器的本底噪声存在差异,单个像元、区域像素的统计结果与全局存在偏差。本研究为提高基于图像传感器的γ射线辐射探测技术,实现无遮光条件下在线辐射探测提供了理论依据和数据支持。
语种:
中文
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金属有机框架材料吸附分离水中铀的应用
作者:
彭莹;张晓文;李密;张宇;吴晓燕
期刊:
化工进展 ,2019年38(7):3227-3242 ISSN:1000-6613
通讯作者:
Zhang, Xiaowen(shawn_zhang@sina.com)
作者机构:
[彭莹; 张晓文; 李密; 张宇; 吴晓燕] College of Resources, Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;[彭莹; 张晓文; 李密; 张宇; 吴晓燕] Hunan;[彭莹; 张晓文; 李密; 张宇; 吴晓燕] 421001, China
关键词:
金属有机框架材料;吸附;水溶液;铀;稳定性;模拟
摘要:
金属有机框架材料(metal-organic frameworks,MOFs)具有极高的比表面积和孔隙率,结构可设计调控,但在水相吸附分离方面存在水稳定和选择吸附性较差、分离困难、合成与再生成本偏高等问题。针对MOFs的缺陷,可以通过有目的的功能化改性从而提升其对目标污染物的吸附性能。本文介绍了MOFs的结构优势,分析了水稳定性的影响因素和判断手段,简述了具有代表性的高水稳定性MOFs材料的特性;根据MOFs改性方法的分类回顾了MOFs及改性MOFs在去除水相中放射性铀的应用;基于不同分析技术探讨了MOFs与铀酰离子的吸附机理;提出推动MOFs在吸附铀方面规模化应用发展的核心是合成高稳定性MOFs,通过改性提高MOFs的选择吸附性能和再生性以及深入研究吸附机理。
语种:
中文
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Influence of PVD-enhancing soft soil ground on the adjacent bridge piles - A 3D FEM analysis
作者:
Li, Hong-Quan;Wei, Li-Min;Feng, Sheng-Yang;Chen, Zhi
期刊:
Civil Engineering Journal ,2018年27(4):561-572 ISSN:1210-4027
作者机构:
[Li, Hong-Quan; Wei, Li-Min; Feng, Sheng-Yang] School of Civil Engineering, Central South University, Changsha;410075, China;[Chen, Zhi] School of Environment and Safety Engineering, University of South China, Hengyang;421001, China;[Li, Hong-Quan; Wei, Li-Min] 410075, China
摘要:
The influence of prefabricated vertical drain (PVD)-enhancing soft soil on the adjacent bridge pile foundation is not sufficiently clear. The related studies are scarce and far behind the requirement of engineering practice. Three-dimensional finite element model (3D FEM) is established to investigate this important issue. Plastic drainage boards in the PVD are modelled by a user-defined element, which considers the axial force and permeability of the plastic drainage board, whereas its weight, shear, and torsion are not considered. The elastoplastic-consolidation coupled model is used for the soils. Field measured results of pore water pressure, ground settlement, and pile cap displacement are used to validate the 3D FEM with good accuracy. A number of useful conclusions can provide guidelines for similar projects and inform designers of the adverse effects of PVD-enhancing soft soil ground on the adjacent bridge pile foundation. © 2018 Czech Technical University. All Rights Reserved.
语种:
英文
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An integrated management system for occupational health and safety and environment in an operating nuclear power plant in East China and its management information system
作者:
Sui, Yang;Ding, Rui;Wang, Hanqing*
期刊:
Journal of Cleaner Production ,2018年183:261-271 ISSN:0959-6526
通讯作者:
Wang, Hanqing
作者机构:
[Sui, Yang; Wang, Hanqing] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Ding, Rui; Sui, Yang] Fujian Fuqing Nucl Power Co Ltd, Fuqing 350300, Peoples R China.
通讯机构:
[Wang, Hanqing] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词:
Information-sharing platform;Integrated management system;Management information system;Occupational health and safety and environment;Operating nuclear power plant
摘要:
In order to implement the integration management of the occupational health and safety and environment (OHSE) in an operating nuclear power plant (ONPP) in East China and help it pass the OHSAS 18001 and ISO 14001 certifications simultaneously rather than separately, an integrated management system (IMS) for OHSE in the ONPP consisting of the occupational health and safety and environment management manual (OHSEMM) and its supportive documents was established to cover the OHSAS 18001 and ISO 14001 standards and IAEA's safety standards on management systems. The management information system for the IMS for the ONPP in East China (MISIMSONPPEC) consisting of the core zone, which includes the information-sharing platform (ISP) and the functional management system (FMS), client and background system was designed for the first time by using browser/server (B/S) structure to overcome the difficulties in implementing the IMS. The applications of the MISIMSONPPEC in the ONPP show that it helped to share and statistically analyze the OHSE data and information from the IMS, to improve the cooperation between departments, to enhance the efficiency of management, and to pass the OHSAS 18001 and ISO 14001 certifications simultaneously rather than separately; and it helped accomplish the integration management of the OHSE in the ONPP.
语种:
英文
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运行核电厂安全生产标准化管理信息系统的研发
作者:
隋阳;丁睿;王汉青
期刊:
核动力工程 ,2018年39(4):152-156 ISSN:0258-0926
通讯作者:
Wang, Hanqing(hqwang2011@126.com)
作者机构:
[隋阳; 王汉青] School of Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;[丁睿] Fujian Fuqing Nuclear Power Co. Ltd., Fuqing;Fujian
通讯机构:
School of Environment and Safety Engineering, University of South China, Hengyang, Hunan, China
关键词:
运行核电厂;安全生产标准化;管理信息系统;信息共享平台;功能管理系统
摘要:
为了解决运行核电厂安全生产标准化建设中信息共享难、工作效率低及各类大量数据统计分析难的问题,研发了运行核电厂安全生产标准化管理信息系统。结果表明,应用该管理信息系统加快了职能处室之间的信息传递,实现了信息共享;优化了管理流程,提高了工作效率;解决了安全生产标准化建设过程中各类大量数据的统计分析问题。
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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4T-PPD-APS光子辐射响应特性分析
作者:
徐守龙;邹树梁;黄有骏;匡雅;郭赞
期刊:
光学学报 ,2018年38(5):0504002-1-0504002-6 ISSN:0253-2239
通讯作者:
Zou, Shuliang(zousl2013@126.com)
作者机构:
[徐守龙; 邹树梁; 匡雅; 郭赞] School of Environmental and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;[黄有骏] Nuclear Power Institute of China, Chengdu;Sichuan
通讯机构:
[Zou, S.] S;School of Environmental and Safety Engineering, University of South China, Hengyang, Hunan, China
关键词:
探测器;互补金属氧化物半导体有源像素传感器;光子辐射响应;钳位光电二极管
摘要:
分析了含有4个晶体管的钳位光电二极管有源像素传感器(4T-PPD-APS)的结构特点以及γ射线光子在像元内的能量沉积过程。通过建立传感器像元及像素阵列仿真计算模型,并结合γ射线辐射响应实验,对有源像素传感器(APS)在不同光子能量及不同放射性水平条件下的响应特性进行了研究。研究结果表明:γ光子在光电二极管空间电荷区内沉积能量并形成扩散光电流是APS发生光子响应现象的根本原因;像素值的平均值随剂量率的增大呈先增大后趋于饱和的趋势;当典型事件区域内出现多个峰值时,像素值的统计值不能准确反映辐射场放射性水平。
语种:
中文
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基于改进蚁群的BP神经网络WSN数据融合算法
作者:
余修武;刘琴;李向阳;张可;肖人榕
期刊:
北京邮电大学学报 ,2018年41(4):91-96 ISSN:1007-5321
作者机构:
[余修武; 刘琴; 李向阳; 张可; 肖人榕] School of Environment and Safety Engineering, University of South China, Hengyang;Hunan;421001, China;State Key Laboratory of Safety and Health for Metal Mines, Sinosteel Maanshan Institute of Mining Research Company, Maanshan;Anhui
关键词:
蚁群算法;反向传播神经网络;无线传感器网络;数据融合;深井
摘要:
为了保证无线传感器网络(WSN)在深井中能有效地工作,提出了一种改进蚁群的反向传播(BP)神经网络WSN数据融合算法(IFA-IACOBP).通过规划蚂蚁运动方向和引入节点剩余能量对蚁群算法启发因子进行改进,优化蚂蚁下一跳节点选择概率,利用改进后的蚁群算法对BP神经网络进行优化,引入井下WSN数据融合,数据经两级融合处理后,能去除大部分冗余信息.仿真实验结果表明,IFA-IACOBP算法能有效减少网络数据通信量,提高数据实时性,降低网络能耗,延长网络寿命.
语种:
中文
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Immobilization of uranium into magnetite from aqueous solution by electrodepositing approach
作者:
Lu, Bing-qing;Li, Mi* ;Zhang, Xiao-wen;Huang, Chun-mei;Wu, Xiao-yan;...
期刊:
Journal of Hazardous Materials ,2018年343:255-265 ISSN:0304-3894
通讯作者:
Li, Mi
作者机构:
[Li, Mi; Lu, Bing-qing; Huang, Chun-mei; Fang, Qi; Zhang, Xiao-wen; Wu, Xiao-yan] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Fang, Qi; Zhang, Xiao-wen; Wu, Xiao-yan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构:
[Li, Mi] U;Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.
关键词:
Electrodeposition;Incorporation;Iron;Magnetite;Uranium
摘要:
Immobilization of uranium into magnetite (Fe<inf>3</inf>O<inf>4</inf>), which was generated from metallic iron by electrochemical method, was proposed to rapidly remove uranium from aqueous solution. The effects of electrochemical parameters such as electrode materials, voltage, electrode gap, reaction time and pH value on the crystallization of Fe<inf>3</inf>O<inf>4</inf>and uranium removal efficiencies were investigated. More than 90% uranium in the solution was precipitated with Fe<inf>3</inf>O<inf>4</inf>under laboratory conditions when uranium concentration range from 0.5 mg/L to 10 mg/L. The Fe<inf>3</inf>O<inf>4</inf>crystallization mechanism and immobilization of uranium was proved by XPS, XRD, TEM, FTIR and VSM methods. The results indicated that the cationic (including Fe<sup>2+</sup>, Fe<sup>3+</sup>and U(VI)) migrate to cathode side under the electric field and the uranium was incorporated or adsorbed by Fe<inf>3</inf>O<inf>4</inf>which was generated at cathode while the pH ranges between 2-7. The uranium-containing precipitate of Fe<inf>3</inf>O<inf>4</inf>can exist stably at the acid concentration below 60 g/L. Furthermore, the precipitate may be used as valuable resources for uranium or iron recycling, which resulted in no secondary pollution in the removal of uranium from aqueous solution. ©2017
语种:
英文
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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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CCD与CMOS像素传感器γ射线电离辐射响应特性对比研究
作者:
徐守龙;邹树梁;黄有骏;郭赞;匡雅
期刊:
发光学报 ,2018年39(6):815-822 ISSN:1000-7032
通讯作者:
Zou, Shu-Liang(zousl2013@126.com)
作者机构:
[徐守龙; 邹树梁; 郭赞; 匡雅] School of Environmental and Safety Engineering, University of South China, Hengyang;421001, China;[黄有骏] Nuclear Power Institute of China, Chengdu;610200, China;[徐守龙; 邹树梁; 郭赞; 匡雅] 421001, China
通讯机构:
[Zou, S.-L.] S;School of Environmental and Safety Engineering, University of South China, Hengyang, China
关键词:
互补金属氧化物半导体;电荷耦合元件;像素传感器;光子电离辐射;辐射响应特性
摘要:
为了研究CCD与CMOS像素传感器对γ射线电离辐射的响应差异,对比研究了4类像素传感器的结构特点和辐射响应特性。通过辐射实验,对各传感器在不同辐射水平条件下的光子响应事件分布、平均灰度值以及典型光子响应事件进行研究。研究结果表明:光子响应程度均与辐射剂量率相关;CCD像素传感器的沟道传输方式使每列像元间的辐射响应更容易相互干扰;平均灰度值随剂量率的增大存在明显的梯度,各积分周期内输出信号灰度值围绕均值上下波动,CCD像素传感器输出信号灰度浮动范围较小;CMOS像素传感器各像元对光子的响应更加明显,CCD像素传感器各像元的响应信号易与相邻像元发生串扰;各类像素传感器典型辐射响应事件区域中发生光子响应的像元数量随剂量率的增大而增多,响应事件并非单个光子的行为,而是反映了多个光子在区域内同时沉积能量的过程。本研究为开发像素传感器的γ射线辐射探测技术和应用提供了重要的理论分析和实验数据支撑。
语种:
中文
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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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Extraction mechanism of depleted uranium exposure by dilute alkali pretreatment combined with acid leaching
作者:
Li, Mi* ;Huang, Chun-Mei;Zhang, Xiao-Wen;Gao, Fang-Ying;Wu, Xiao-Yan;...
期刊:
Hydrometallurgy ,2018年180:201-209 ISSN:0304-386X
通讯作者:
Li, Mi
作者机构:
[Gao, Fang-Ying; Li, Mi; Huang, Chun-Mei; Fang, Qi; Zhang, Xiao-Wen; Tan, Wen-Fa; Wu, Xiao-Yan; Zhang, De] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiao-Wen; Wu, Xiao-Yan] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
通讯机构:
[Li, Mi] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.
关键词:
Uranium;Tailings;Leaching;Gangue
摘要:
Uranium recovery from tailings is difficult because of the encapsulation of uranium by high content of gangue minerals. Uranium separation from gangue minerals has also been a key point in improving uranium extraction in the field of low-grade uranium resource recovery. This study proposed a high-efficiency alkali-pretreatment followed by acid leaching (two-step leaching) process for improving uranium extraction from uranium tailings. The main principle was to use a low concentration of alkaline solution to selectively comminute gangue minerals and to promote the formation of micropores in particles, providing a "path" for sulfuric acid to enter the interior of the uranium minerals. The effects of process parameters on uranium extraction and the changes in elemental composition, phase composition, morphology, and aperture of the tailings were investigated to show the mechanism of gangue comminution. Results showed that the uranium extraction percent without alkali pretreatment was only 63.91%, while it increased to 90.80% for the two-step leaching process under the same conditions. The low concentration of alkaline solution can selectively decompose gangue minerals, and dilute acid can then further reduce the degree of crystallinity of the silicates. Thus, a large number of mesopores in the tailings formed to improve the exposure ratio of uranium to the leaching agent. This new discovery may aid in the recovery of valuable metals from low-grade ore or tailings with high gangue content.
语种:
英文
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Detecting Confident Information Coverage Holes in Industrial Internet of Things: An Energy-Efficient Perspective
作者:
Deng, Xianjun;Yang, Laurence T.;Yi, Lingzhi* ;Wang, Minghua;Zhu, Zhiliang
期刊:
IEEE COMMUNICATIONS MAGAZINE ,2018年56(9):68-73 ISSN:0163-6804
通讯作者:
Yi, Lingzhi
作者机构:
[Wang, Minghua; Deng, Xianjun] Univ South China, Dept Commun Engn, Hengyang, Peoples R China.;[Yang, Laurence T.] St Francis Xavier Univ, Dept Comp Sci, Antigonish, NS, Canada.;[Yi, Lingzhi] USC, Sch Environm Protect & Safety Engn, Hengyang, Peoples R China.;[Yi, Lingzhi] USC, Sch Civil Engn, Hengyang, Peoples R China.;[Zhu, Zhiliang] Wenzhou Univ, Coll Phys & Elect Informat Engn, Wenzhou, Zhejiang, Peoples R China.
通讯机构:
[Yi, Lingzhi] U;USC, Sch Environm Protect & Safety Engn, Hengyang, Peoples R China.;USC, Sch Civil Engn, Hengyang, Peoples R China.
摘要:
Radiological pollution, which poses a great threat to public health and environment safety, is one of the critical concerns in nuclear industries. The ever growing IIoT is a promising network paradigm for monitoring the radiological pollution level in uranium mill tailings. Coverage, as one of the most decisive indicators for evaluating the success of IIoT-based radiological pollution monitoring, reflects how well the sensing fields of interest are monitored. Nevertheless, the possible coverage holes resulting from sensors' random deployment, energy depletion, and hazardous conditions may remarkably lower the QoS, especially the coverage performance of IIoT-based radiological pollution monitoring. In order to avoid the potential emerging coverage holes' negative effects on the network QoS, this article focuses on the coverage hole detection issue from an energy-efficient perspective. By exploiting the merits of the CIC model, this article develops an EECICHD that detects the CIC holes by fully considering the sensor nodes' energy dissipation as well as their communication abilities. The EECICHD makes full use of the intrinsic spatial distribution correlation of monitored variables and collaborative sensing among neighboring sensors for improving the efficiency of CIC holes detection. Through simulation experiments, we show that the proposed EECICHD scheme can efficiently localize and determine the locations and number of the CIC holes. © 1979-2012 IEEE.
语种:
英文
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High efficiency microwave-assisted synthesis of quinoline from acrolein diethyl acetal and aniline utilizing Ni/Beta catalyst
作者:
Li, An;Yang, Zan;Yang, Tao;Luo, Cai-Wu;Chao, Zi-Sheng* ;...
期刊:
Catalysis Communications ,2018年115:21-25 ISSN:1566-7367
通讯作者:
Zhou, Cong-Shan;Chao, Zi-Sheng
作者机构:
[Li, An; Yang, Tao; Zhou, Cong-Shan; Yang, Zan] Hunan Inst Sci & Technol, Coll Chem & Chem Engn, Yueyang 414000, Peoples R China.;[Luo, Cai-Wu] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Chao, Zi-Sheng] Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Hunan, Peoples R China.
通讯机构:
[Zhou, Cong-Shan] H;[Chao, Zi-Sheng] C;Hunan Inst Sci & Technol, Coll Chem & Chem Engn, Yueyang 414000, Peoples R China.;Changsha Univ Sci & Technol, Coll Mat Sci & Engn, Changsha 410114, Hunan, Peoples R China.
关键词:
Acrolein diethyl acetal;Beta zeolite;Microwave-assisted;Quinolines
摘要:
A facile and solvent-free microwave-assisted approach to quinoline was developed by utilizing both acrolein diethyl acetal and aniline as reagents, firstly employing Ni/Beta zeolite as mild, ecofriendly and low-cost solid catalyst. As high as 83% yield of quinoline was quickly achieved at a short microwave time. The results indicated that the effect of Ni on Beta zeolite not only significantly promoted conversion of acrolein diethyl acetal to effective intermediate but also dramatically accelerated dehydrogenation rate of tetrahydroquinoline/dihydroquinoline to quinoline. © 2018 Elsevier B.V.
语种:
英文
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