Effect of Si/Al ratios on the structure and catalytic properties of alkaline-treated ZSM-5 catalysts
作者：
Luo, Cai-Wu;Li, Xiang-Yang;Chao, Zi-Sheng
期刊：
Materials Science Forum ,2017年896:141-147 ISSN：0255-5476
作者机构：
[Luo, Cai-Wu; Li, Xiang-Yang] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China;[Chao, Zi-Sheng] College of Materials Science and Engineering, Changsha University of Science &, Technology, Changsha, 410114, China
摘要：
A series of hierarchical HZSM-5 catalysts were synthesized by alkaline (denoted as HZSM-5-At) and/or alkaline-acid (denoted as HZSM-5-At-acid) treatments, and they as catalyst pairs were employed for the synthesis of glycerol and ammonia toward pyridine bases in a series-connected two-stage reactor. The characterization was analysed by means of N2-physorption and NH3-TPD techniques. The catalytic evaluation showed that the lower Si/Al ratio (Si/Al = 25 before treatment) in catalyst pairs (HZSM-5-At + ZnO/HZSM-5-At-acid) possessed the highest total yield of pyridine bases among all the catalyst pairs, but the suitable Si/Al ratio in alkaline-treated ZSM-5 (Si/Al = 38 before treatment) in the first stage of reactor and ZnO/HZSM-5-At-acid (Si/Al = 25 before treatment) in the second stage of reactor had the stronger stability relative to other catalyst pairs. The characterization revealed that the amount of acid sites play a vital role in the formation of pyridine bases whereas the appearance of mesoporous structure and the declined concentration of acid sites were main reasons for promoting the stability. ©2017 Trans Tech Publications, Switzerland.
语种：
英文
展开
Numerical simulation of migration behavior of uranium ore dust particles in the human respiratory tract
作者：
Ye, Yong-jun* ;Yin, An-song;Li, Zhi;Lei, Bo;Ding, De-xin
期刊：
IOP Conference Series: Earth and Environmental Science ,2017年61(1) ISSN：1755-1307
通讯作者：
Ye, Yong-jun
作者机构：
[Yin, An-song; Ye, Yong-jun; Li, Zhi; Ding, De-xin; Lei, Bo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Ye, Yong-jun; Ding, De-xin] 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.;Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
会议名称：
3rd International Conference on Energy Materials and Environment Engineering (ICEMEE)
会议时间：
MAR 10-12, 2017
会议地点：
Bangkok, THAILAND
会议主办单位：
[Ye, Yong-jun;Yin, An-song;Li, Zhi;Lei, Bo;Ding, De-xin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.^[Ye, Yong-jun;Ding, De-xin] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
会议论文集名称：
IOP Conference Series-Earth and Environmental Science
摘要：
There is a certain concentration of radioactive dust particles in the air of workplace of underground uranium mines. Some small diameter particles will pass through the masks and enter the respiratory tract which will cause radiation damage to the human body. In order to study deposition regularity of uranium dust in the human respiratory tract, in this paper, we firstly use the RNG turbulence model to simulate the gas flow field in the human respiratory tract Z<inf>0</inf>∼Z<inf>3</inf>level under different respiratory intensity. Then we use DPM discrete phase model to simulate the concentration, particle size distribution, deposition rate and deposition share of uranium dust particles after being filtered through the masks in the human respiratory tract Z<inf>0</inf>to Z<inf>3</inf>bronchus. According to the simulation results, we have got the following conclusions: the particles' number concentration of uranium dust after being filtered through the mask in the human respiratory tract basically decreases with the increasing of particle size under different respiratory intensities on the environment of uranium mine. In addition, the intensity of respiration and the mass concentration of particles have an important influence on the deposition rate and the deposition of particles in the respiratory tract. ©Published under licence by IOP Publishing Ltd.
语种：
英文
展开
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：
Predictive model;Queuing theory;Radon contamination;Shaft station;Underground uranium mine
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. (C) 2016 Elsevier Ltd. All rights reserved.
语种：
英文
展开
Kinetics of Uranium Extraction from Uranium Tailings by Oxidative Leaching
作者：
Zhang, Biao;Li, Mi* ;Zhang, Xiaowen;Huang, Jing
期刊：
JOM ,2016年68(7):1990-2001 ISSN：1047-4838
通讯作者：
Li, Mi
作者机构：
[Zhang, Biao; Li, Mi; Huang, Jing; Zhang, Xiaowen] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Zhang, Xiaowen] 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.;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
关键词：
Uranium;Sulfuric Acid Solution;Uranium Concentration;Uranium Oxide;Shrink Core Model
摘要：
Extraction of uranium from uranium tailings by oxidative leaching with hydrogen peroxide (H<inf>2</inf>O<inf>2</inf>) was studied. The effects of various extraction factors were investigated to optimize the dissolution conditions, as well as to determine the leaching kinetic parameters. The behavior of H<inf>2</inf>O<inf>2</inf>in the leaching process was determined through scanning electron microscopy-energy dispersive x-ray spectroscopy (SEM-EDX) and x-ray diffraction analysis of leaching residues. Results suggest that H<inf>2</inf>O<inf>2</inf>can significantly improve uranium extraction by decomposing the complex gangue structures in uranium tailings and by enhancing the reaction rate between uranium phases and the leaching agent. The extraction kinetics expression was changed from 1 − 3(1 − α)<sup>2/3</sup> + 2(1 − α) = K<inf>0</inf>(H<inf>2</inf>SO<inf>4</inf>)<sup>−0.14903</sup>(S/L)<sup>−1.80435</sup>(R<inf>o</inf>)<sup>0.20023</sup>e<sup>−1670.93/T</sup>t (t ≥ 5) to 1 − 3(1 − α)<sup>2/3</sup> + 2(1 − α) = K<inf>0</inf>(H<inf>2</inf>SO<inf>4</inf>)<sup>0.01382</sup>(S/L)<sup>−1.83275</sup>(R<inf>o</inf>)<sup>0.25763</sup>e<sup>−1654.59/T</sup>t (t ≥ 5) by the addition of H<inf>2</inf>O<inf>2</inf>in the leaching process. The use of H<inf>2</inf>O<inf>2</inf>in uranium leaching may help in extracting uranium more efficiently and rapidly from low-uranium-containing ores or tailings. ©2016, The Minerals, Metals & Materials Society.
语种：
英文
展开
表面活性剂提高铀矿石浸出率研究
作者：
Lü* ;, Yang;, Junwen;Zhou, Jianliang;...
期刊：
稀有金属 ,2016年40(2):182-187 ISSN：0258-7076
通讯作者：
Lü, Junwen(jwlv9892@aliyun.com)
作者机构：
南华大学核科学技术学院, 湖南, 衡阳, 421001;南华大学环境保护与安全工程学院, 湖南, 衡阳, 421001;南华大学核资源工程学院, 湖南, 衡阳, 421001;[吕洋; Zhou, Jianliang] 南华大学核科学技术学院, 湖南, 衡阳, 421001;[吕俊文] 南华大学环境保护与安全工程学院, 湖南, 衡阳, 421001
通讯机构：
School of Environment Protection and Safety Engineering, University of South China, Hengyang, China
关键词：
表面活性剂;表面张力;渗透性;铀浸出率
摘要：
为了解决铀矿堆浸过程中渗透性差以及浸出率不高的问题, 通过添加表面活性剂提高渗透性而强化铀矿石浸出。 本研究采用静态实验研究3种不同的表面活性剂脂肪酸甲酯磺酸盐(MES)、 十二烷基硫酸钠(SDS)、 吐温80对铀浸出率的影响, 并测定溶浸剂的表面张力, 选出使铀浸出率提升最大的表面活性剂后确定其最佳用量; 再通过动态柱实验进一步研究铀矿堆浸过程中表面活性剂对渗透性大小的改变及铀浸出率的影响。 静态实验结果表明: 3种表面活性剂均能提高铀浸出率, 其中十二烷基硫酸钠对铀的浸出效果最好且使溶浸剂表面张力降低最低, 为52.94%; 接近临界胶束浓度时铀浸出率最高, 故选用0.008 mol·L~(-1)的十二烷基硫酸钠进行动态实验。 动态实验结果表明: 十二烷基硫酸钠的加入最终使实验柱的渗透系数提高至4.6倍, 铀的浸出率由48.41%提升至60.20%, 增加了11.79%。 表面活性剂增大了铀矿石堆浸过程中的渗透性, 使铀浸出率提高。
语种：
中文
展开
Application of a combination of municipal solid waste incineration fly ash and lightweight aggregate in concrete
作者：
Tan, Wen-fa* ;Lv, Jun-wen;Deng, Qin-wen;Zhang, Xiao-wen
期刊：
Journal of Adhesion Science and Technology ,2016年30(8):866-877 ISSN：0169-4243
通讯作者：
Tan, Wen-fa
作者机构：
[Tan, Wen-fa; Zhang, Xiao-wen; Lv, Jun-wen; Deng, Qin-wen] Univ South China, Dept Environm Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Tan, Wen-fa] U;Univ South China, Dept Environm Engn, Hengyang 421001, Peoples R China.
关键词：
Fly ash;hazardous waste;lightweight aggregate;concrete
摘要：
This paper highlights significant findings from focusing on developing a sustainable lightweight aggregate (LWA) concrete, which replaced Portland cement partially with municipal solid waste incineration fly ash (MSWI FA) and all of the conventional coarse aggregate with LWA sintered by MSWI FA, shale, and sludge. A series of four experiments, differing in dosage of MSWI FA and aggregate, were conducted for this project. The results of this study generally showed that appropriate amount of MSWI FA substitution for cement has no significantly lowered the compressive strengths of LWA concrete, while it can lower the oven-dry density and the thermal conductivity. The optimum performance of LWA concrete (after 28 days of curing) is as follows: (1) slump flow of 700 mm, (2) compressive strength of 30.14 MPa, (3) dry apparent density of 1.66 g/cm3, (4) thermal conductivity of 0.73 W (m K)−1; the mixture ratio of LWA, fly ash, cement, and fine sand is 3.0: 0.1: 0.9: 2.0 based on dry weight. Meanwhile, the results of leaching test are much lower than the concentration limits of hazardous constituents of hazardous waste identification standard (GB/T 5083.3-2007) and landfill standard (GB16889-2008).
语种：
英文
展开
爆破后压入式通风独头巷道内氡的运移模型
作者：
叶勇军;江俊廷;丁德馨;钟永明;谢超
期刊：
原子能科学技术 ,2016年50(3):571-576 ISSN：1000-6931
通讯作者：
Ding, De-Xin(dingdxzzz@163.com)
作者机构：
南华大学环境保护与安全工程学院, 铀矿冶生物技术国防重点学科实验室, 湖南, 衡阳, 421001;南华大学环境保护与安全工程学院, 湖南, 衡阳, 421001;南华大学, 铀矿冶生物技术国防重点学科实验室, 湖南, 衡阳, 421001;[叶勇军] 南华大学环境保护与安全工程学院, 铀矿冶生物技术国防重点学科实验室, 湖南, 衡阳, 421001;[江俊廷; 钟永明; 谢超] 南华大学环境保护与安全工程学院, 湖南, 衡阳, 421001
通讯机构：
Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
关键词：
铀矿;独头巷道;爆破;氡活度浓度;压入式通风
摘要：
为有效指导铀矿井下独头巷道的通风设计,基于质量守恒定律和置换通风理论,首先建立了描述爆破后压入式通风独头巷道内抛掷空间和风流末端氡活度浓度随通风时间变化的计算模型,利用该模型得到了达到氡活度浓度限值条件的最短排氡通风时间的确定方法;然后分析了不同参数对风流末端氡活度浓度以及最短排氡通风时间的影响。结果表明,爆破后,独头巷道风流末端氡活度浓度在一定通风时间内保持不变,之后瞬间增至峰值,最终逐渐衰减至稳定;在其他参数一定的情况下,风流末端氡活度浓度开始剧增的时间随巷道长度的增加而减小,随风量增加而增大;风流末端氡活度浓度衰减速率随风量的增加而增大;风流末端氡活度浓度峰值随掘进面铀品位的增加而增大;最短排氡通风时间随巷道长度和掘进面铀品位的增加而增大,随通风量的增加而减小。
语种：
中文
展开
水浸颗粒堆积型射气介质氡析出规律的理论研究
作者：
叶勇军;赵娅利;代鑫涛;冯胜洋;郭倩;...
期刊：
原子能科学技术 ,2016年50(9):1721-1728 ISSN：1000-6931
作者机构：
[叶勇军] School of Environment Protection and Safety Engineering, University of South China, Hengyang, 421001, China;[叶勇军; 代鑫涛; 张运峰; 郭倩; 赵娅利; 冯胜洋] Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, China
关键词：
铀矿;水浸;颗粒堆积型射气介质;氡析出;数学模型
摘要：
铀尾矿库和地表浸铀铀矿堆是一种颗粒堆积型射气介质,其水位的变化和覆水厚度对氡迁移与析出的影响不容忽视。为揭示这类介质表面氡析出的规律,本文基于菲克定律和气液两相界面氡的传输理论,建立了水浸颗粒堆积型射气介质氡的一维传输-扩散数学模型,并获得稳态条件下气液两相体系中氡浓度分布的解析解和氡析出率的计算公式。通过研究,获得以下结论:1)水位为0m时,颗粒堆积型射气介质表面氡析出率随介质厚度的增大而增大,其增长率随厚度的增大而减小;2)介质表面氡析出率随水位的增大先增大后减小;3)当水体高度大于射气介质厚度时,覆水表面氡析出率随覆水厚度的增大而减小,随覆水氡扩散系数的增大而增大。
语种：
中文
展开
Current drive with combined electron cyclotron wave and high harmonic fast wave in tokamak plasmas
作者：
Li, J. C.;Gong, X. Y.* ;Dong, J. Q.;Wang, J.;Zhang, N.;...
期刊：
PHYSICS OF PLASMAS ,2016年23(12):122504 ISSN：1070-664X
通讯作者：
Gong, X. Y.
作者机构：
[Yin, C. Y.; Li, J. C.; Gong, X. Y.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Li, J. C.] Peking Univ, Dept Phys, FSC, Beijing 100871, Peoples R China.;[Li, J. C.] Peking Univ, State Key Lab Nucl Phys & Technol, FSC, Beijing 100871, Peoples R China.;[Zhang, N.; Dong, J. Q.; Wang, J.] Southwestern Inst Phys, POB 432, Chengdu 610041, Peoples R China.;[Dong, J. Q.] Zhejiang Univ, Inst Fus Theory & Simulat, Hangzhou 310058, Zhejiang, Peoples R China.
通讯机构：
[Gong, X. Y.] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
plasma density;plasma hybrid waves;plasma simulation;plasma toroidal confinement;refractive index;Tokamak devices
摘要：
The current driven by combined electron cyclotron wave (ECW) and high harmonic fast wave is investigated using the GENRAY/CQL3D package. It is shown that no significant synergetic current is found in a range of cases with a combined ECW and fast wave (FW). This result is consistent with a previous study [Harvey et al., in Proceedings of IAEA TCM on Fast Wave Current Drive in Reactor Scale Tokamaks (Synergy and Complimentarily with LHCD and ECRH), Arles, France, IAEA, Vienna, 1991]. However, a positive synergy effect does appear with the FW in the lower hybrid range of frequencies. This positive synergy effect can be explained using a picture of the electron distribution function induced by the ECW and a very high harmonic fast wave (helicon). The dependence of the synergy effect on the radial position of the power deposition, the wave power, the wave frequency, and the parallel refractive index is also analyzed, both numerically and physically.
语种：
英文
展开
Environmental effects of coal gangue and its utilization
作者：
Tan, W-F.;Wang, L-A.* ;Huang, C.
期刊：
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS ,2016年38(24):3716-3721 ISSN：1556-7036
通讯作者：
Wang, L-A.
作者机构：
[Tan, W-F.] Univ South China, Dept Environm Engn, Hengyang, Peoples R China.;[Huang, C.; Tan, W-F.; Wang, L-A.] Chongqing Univ, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing, Peoples R China.;[Wang, L-A.] Chongqing Univ, Sch Resources & Environm Sci, 174 Shazhengjie, Chongqing 400044, Peoples R China.
通讯机构：
[Wang, L-A.] C;Chongqing Univ, Sch Resources & Environm Sci, 174 Shazhengjie, Chongqing 400044, Peoples R China.
关键词：
Coal gangue;environmental effects;utilization;lightweight aggregates;natural resources
摘要：
Coal gangue has accumulated huge coal gangue piles, occupying lots of land as well as having striking influence on the neighboring environmental effects. This paper seeks a new way of coal gangue treatment in which the coal gangue blended with shale and sludge was sintered in rotary kiln to form lightweight aggregates. The results show that the optimum mixture ratio of coal gangue, shale, and sludge is 50, 40, and 10 wt% and the corresponding indicators of aggregates obtained are: (a) bulk density of 658 kg/m<sup>3</sup>, (b) granule strength of 643N, (c) 1 h absorption water to be 13.8%. ©2016 Taylor & Francis.
语种：
英文
展开
Deactivation and regeneration on the ZSM-5-based catalyst for the synthesis of pyridine and 3-picoline
作者：
Luo, Cai-Wu;Feng, Xiao-Yan;Liu, Wei;Lia, Xiang-Yang;Chao, Zi-Sheng*
期刊：
Microporous and Mesoporous Materials ,2016年235:261-269 ISSN：1387-1811
通讯作者：
Chao, Zi-Sheng
作者机构：
[Luo, Cai-Wu; Lia, Xiang-Yang] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Luo, Cai-Wu; Chao, Zi-Sheng; Feng, Xiao-Yan] Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chem Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.;[Liu, Wei] Georgia Inst Technol, Sch Chem & Biomol Engn, 500 10th St NW, Atlanta, GA 30332 USA.;[Liu, Wei] Georgia Inst Technol, RBI Georgia Tech, 500 10th St NW, Atlanta, GA 30332 USA.
通讯机构：
[Chao, Zi-Sheng] H;Hunan Univ, Coll Chem & Chem Engn, State Key Lab Chem Biosensing & Chemometr, Changsha 410082, Hunan, Peoples R China.
关键词：
ZSM-5;Deactivation;Regeneration;Residual coke;Dealumination
摘要：
The deactivation and regeneration of the ZSM-5-based catalyst was investigated in the reaction of acrolein diethyl acetal and ammonia toward pyridine and 3-picoline. The coke was the main reason leading to deactivation for all the tested catalysts, and it was basically combusted at high temperature under the air and water streams in order to recover the initial catalytic performance. The best catalyst through the reaction-regeneration treatment could effectively promote the formation of pyridine and 3-picoline. The results showed that the total yield of pyridine and 3-picoline was raised above 20% while the reaction was operated the 10th reaction-regeneration cycle relative to the 1st reaction at TOS (time on stream) = 1–3 h. The catalysts were characterized by means of XRD, N<inf>2</inf>-physisorption, FT-IR and NH<inf>3</inf>-TPD techniques. By relating the performance and structure of the catalyst, it was found that the dealumination and the residual coke were responsible for boosting the catalytic activity after several reaction-regeneration cycles. The dealumination generated more mesopores and less acidity while the residual coke resulted in lowering the acidity. The relationship between the catalyst and the regeneration was well established. ©2016 Elsevier Inc.
语种：
英文
展开
采用HF和HClO_4从铀尾矿中浸出铀的试验研究
作者：
李密;黄婧;戴士祥;张晓文;张彪;...
期刊：
中国矿业大学学报 ,2016年45(3):639-645 ISSN：1000-1964
通讯作者：
Li, Mi(enemy_1983@163.com)
作者机构：
[李密; 戴士祥; 黄婧; 张晓文; 张彪] School of Environment Protection and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China;[丁德馨] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, Hunan, 421001, China;[李密; 张晓文] Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, Hunan, 421001, China
通讯机构：
School of Environment Protection and Safety Engineering, University of South China, Hengyang, Hunan, China
关键词：
铀尾矿;浸出;强化机理;脉石
摘要：
为了从低品位铀尾矿中回收铀资源,在详细分析了铀尾矿工艺矿物学性质的基础上,提出了以硫酸为浸出剂,HF和HClO_4为强化剂的氧化强化浸铀工艺,研究了工艺参数对铀浸出的影响,并通过X射线衍射仪、激光粒度仪及扫描电镜等手段分析铀尾矿浸出过程中的物相、粒度及形貌特征变化,揭示了HF和HClO_4对铀尾矿浸出的强化作用机理.研究结果表明:HF可分解硅酸盐类矿物结构,而HClO_4可对脉石颗粒表面造成"溶蚀",二者均可促进脉石颗粒与铀的解离,但HClO_4的作用效果低于HF.当浸出温度为50 ℃,硫酸浓度为1.5 mol/L,浸出时间为80 min,液固质量比为12时,HF和HClO_4对铀的浸出率分别为96%和78%.
语种：
中文
展开
Effects of feldspar and salinity on the mineral sequestration capacity of CO2 in high-salinity aquifers
作者：
Fang, Qi* ;Li, Yilian;Peng, Guojian;Cheng, Peng;Lv, Junwen
期刊：
Environmental Earth Sciences ,2016年75(18):1-13 ISSN：1866-6280
通讯作者：
Fang, Qi
作者机构：
[Fang, Qi; Lv, Junwen] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Yilian] China Univ Geosci, Sch Environm Studies, Wuhan 430074, Peoples R China.;[Peng, Guojian] Univ South China, Sch Comp Sci & Technol, Hengyang 421001, Peoples R China.;[Cheng, Peng] Team 217 Hunan Nonferrous Geol Explorat Bur, Hengyang 421001, Peoples R China.
通讯机构：
[Fang, Qi] U;Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Peoples R China.
关键词：
CO2 geological storage;Mineral sequestration capacity;Feldspar;Salinity;High-salinity aquifers
摘要：
Mineral sequestration of CO2 is considered to be the safest mechanism in the long-term storage of CO2 in deep saline aquifers. This study aims to investigate the effect of feldspar and salinity on the mineral sequestration capacity of CO2 in deep high-salinity brine aquifers by taking Jiangling Depression of Jianghan Basin for instance. Numerical simulation on the long-term geochemical reaction and transport was performed by taking TOUGHREACT as the simulation tool. Simulation results indicate that the effect of feldspar on the mineral trapping capacity of CO2 does not depend on the total content of feldspar, but depends on feldspar type and relative content. With Mg-rich minerals such as chlorite or dolomite present, the mineral composition abundant in K-feldspar is less favorable for the mineral sequestration capacity of CO2 for the reason that a large amount of illite precipitates, consuming a lot of Al3+ in the aqueous solution, thereby limiting the precipitation of dawsonite, especially for the high-temperature sedimentary environment. In addition, the effect of salinity on the mineral sequestration capacity of CO2 represents two aspects: one for the longer migration distance due to the lower solubility of higher salinity and the other for CO2 mineral trapping capacity per 1m3 medium which is not in simple decreased with salinity, depending on K-feldspar present or not. For the mineral composition with K-feldspar present, CO2 mineral trapping capacity decreases with salinity, while with albite instead of K-feldspar, it increases with salinity owing to more precipitation of dawsonite. © 2016, Springer-Verlag Berlin Heidelberg.
语种：
英文
展开
Investigation of gamma ray shielding efficiency and mechanical performances of concrete shields containing bismuth oxide as an environmentally friendly additive
作者：
Yao, Ya;Zhang, Xiaowen* ;Li, Mi;Yang, Rong;Jiang, Tianjiao;...
期刊：
Radiation Physics and Chemistry ,2016年127:188-193 ISSN：0969-806X
通讯作者：
Zhang, Xiaowen
作者机构：
[Yao, Ya; Yang, Rong; Jiang, Tianjiao] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 42100, Peoples R China.;[Li, Mi; Lv, Junwen; Zhang, Xiaowen] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Zhang, Xiaowen] U;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Hunan, Peoples R China.
关键词：
Bismuth oxide;Compressive strength;Concrete;Lead oxide;Linear attenuation coefficient
摘要：
Concrete has a proven ability to attenuate gamma rays and neutrons without compromising structural property;therefore, it is widely used as the primary shielding material in many nuclear facilities. Recently, there is a tendency toward using various additives to enhance the shielding properties of these concrete mixtures. However, most of these additives being used either pose hygiene hazards or require special handling processes. It would be ideal if environmentally friendly additives were available for use. The bismuth oxide (Bi<inf>2</inf>O<inf>3</inf>) additive shows promise in various shielding applications due to its proven radiation attenuation ability and environmentally friendly nature. To the best of our knowledge, however, Bi<inf>2</inf>O<inf>3</inf>has never been used in concrete mixtures. Therefore, for this research, we fabricated the Bi<inf>2</inf>O<inf>3</inf>-based concrete mixtures by adding Bi<inf>2</inf>O<inf>3</inf>powder in the ordinary concrete mixture. Concrete mixtures with lead oxide (PbO) additives were used for comparison. Radiation shielding parameters like the linear attenuation coefficients (LAC) of all these concrete mixtures showing the effects of the Bi<inf>2</inf>O<inf>3</inf>additions are presented. The mechanical performances of concrete mixtures incorporated with Bi<inf>2</inf>O<inf>3</inf>additive were also investigated. It suggested that the concrete mixture containing 25% Bi<inf>2</inf>O<inf>3</inf>powder (B5 in this study) provided the best shielding capacity and mechanical performance among other mixes. It has a significant potential for application as a structural concrete where radiological protection capability is required. ©2016 Elsevier Ltd
语种：
英文
展开
低频机械振动含瓦斯煤孔隙率方程及其试验
作者：
李树刚;赵勇;许满贵
期刊：
煤炭学报 ,2016年41(10):2612-2619 ISSN：0253-9993
通讯作者：
Zhao, Yong(zy6863368@163.com)
作者机构：
[许满贵; 李树刚] School of Energy Engineering, Xi'an University of Science and Technology, Xi'an, 710054, China;[赵勇] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China
通讯机构：
School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
关键词：
低频机械振动;骨架变形;体积变化;孔隙率;单轴抗压强度
摘要：
为研究低频机械振动作用对含瓦斯煤孔隙率的影响,建立煤体孔隙瓦斯压力、吸附膨胀力、振动衰减挤压应力作用下振动动态孔隙率方程。采用前人得出的煤体孔隙率与单轴抗压强度变化规律,以及不同频率、不同时间振动型煤试件后的煤体单轴抗压强度变化试验对方程进行检验,结果显示: 低频振动作用下,振动频率相同,振动时间越长,煤体单轴抗压强度越小,孔隙率越大; 振动时间相同,振动频率越小,煤体单轴抗压强度越大,孔隙率越小,且30 Hz与20 Hz单轴抗压强度、孔隙率差值要小于20 Hz与10 Hz之差。表明振动使煤体孔隙率增大,从而减小了煤体单轴抗压强度,且振动频率从10,20,30 Hz逐渐增加,孔隙率逐渐变大,单轴抗压强度相应变小,计算孔隙率能正确反映振动后煤体单轴抗压强度变化规律。对比计算孔隙率和试验单轴抗压强度关系进一步得到前人得出的单轴抗压强度随孔隙率变化曲线呈现类指数变化规律,因此方程计算值能正确反映低频机械振动作用下不同振动频率、振动时间影响煤体孔隙率变化规律。
语种：
中文
展开
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：
Model;Fragmented uranium ore;Water level;Radon concentration;Radon exhalation rate
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.
语种：
英文
展开
Co-combustion Kinetics Parameters of MSWI Fly Ash with Sawdust and Shale under Different Heating Rates and Atmospheres
作者：
Tan, W. -F.;Wang, L. -A.* ;Huang, C.;Li, J. -X.;Yang, W.
期刊：
ENERGY SOURCES PART A-RECOVERY UTILIZATION AND ENVIRONMENTAL EFFECTS ,2015年37(22):2415-2421 ISSN：1556-7036
通讯作者：
Wang, L. -A.
作者机构：
[Tan, W. -F.] Univ South China, Dept Environm Engn, Hengyang, Peoples R China.;[Li, J. -X.; Wang, L. -A.; Huang, C.; Yang, W.] Chongqing Univ, State Key Lab Coal Mine Disaster Dynam & Control, Chongqing 400044, Peoples R China.;[Wang, L. -A.] Chongqing Univ, Sch Resources & Environm Sci, 174 Shazhengjie, Chongqing 400044, Peoples R China.
通讯机构：
[Wang, L. -A.] C;Chongqing Univ, Sch Resources & Environm Sci, 174 Shazhengjie, Chongqing 400044, Peoples R China.
关键词：
co-combustion;lightweight aggregates;municipal solid waste incineration fly ash;sawdust;shale;thermogravimetry-differential thermogravimetry-differential scanning calorimetry analysis
摘要：
The kinetic parameters for the co-combustion of municipal solid waste incineration fly ash, sawdust, and shale have been determined by a sync analyzer, aiming to simulate the manufacture of lightweight aggregates process. Experiments were carried out with about each 10-mg samples at different heating rates in air and argon atmospheres, respectively. The results indicate that behaviors of the mixture can be broadly divided into four separate events. The total mass loss reached the maximum at 20 K·min<sup>-1</sup>. There appears to be no unanimous formula of the degree of the total mass loss in different gas atmospheres. ©Copyright ©Taylor & Francis Group, LLC.
语种：
英文
展开
Preparation of Mn3O4 from low-grade rhodochrosite ore by chemical bath deposition method
作者：
Jing Zhao;Longjun Xu;Taiping Xie;Chao Xie
期刊：
地球化学学报(英文) ,2015年34(1):55-61 ISSN：2096-0956
通讯作者：
Zhao, Jing(20077313@cqu.edu.cn)
作者机构：
[Jing Zhao; Taiping Xie; Longjun Xu] State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, 400044, China;[Chao Xie] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China
通讯机构：
[Jing Zhao] S;State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing University, Chongqing, China
关键词：
Chemical bath deposition method;Low-grade rhodochrosite ore;Mn3O4
摘要：
Mn<inf>3</inf>O<inf>4</inf>was prepared with the chemical bath deposition (CBD) method. A MnSO<inf>4</inf>solution was obtained by the leaching and purifying of low-grade rhodochrosite ore (LGRO), which was used as raw material. The preparation procedures were studied and promoted. The results showed that the Mn<inf>3</inf>O<inf>4</inf>with the highest purity and highest specific surface area could be obtained under the following processes. An MnSO<inf>4</inf>solution of 1.0 mol/L was added into a beaker under a flow rate of 30 mL/h. The pH of the reaction solution was adjusted to 10 using NH<inf>3</inf>·H<inf>2</inf>O at 80 °C. Then the solids were washed and dried at 200 °C for 2.5 h. The total Mn content (TMC) of Mn<inf>3</inf>O<inf>4</inf>was 72.0 %. The ionic distributions was formulated as [Mn<sup>2+</sup>][Mn<inf>0.3024</inf><sup>2+</sup>Mn<inf>0.2937</inf><sup>3+</sup>Mn<inf>0.3786</inf><sup>4+</sup>□<inf>0.0254</inf>]<inf>2</inf>O<inf>4</inf>. The average crystallite size of Mn<inf>3</inf>O<inf>4</inf>with a tetragonal hausmannite structure was found to be about 35 nm by X-ray diffraction (XRD) analysis. The BET specific surface area of the Mn<inf>3</inf>O<inf>4</inf>measured was 32 m<sup>2</sup>/g. ©2015, Science Press, Institute of Geochemistry, CAS and Springer-Verlag Berlin Heidelberg.
语种：
英文
展开
Dynamic shear modulus and damping ratio of aeolian soils
作者：
Feng, Shengyang;Li, Xiangyang;Wang, Shuyun;Chen, Zhi
期刊：
Electronic Journal of Geotechnical Engineering ,2015年20(25):12113-12120 ISSN：1089-3032
通讯作者：
Feng, Shengyang(fengshengyang13@163.com)
作者机构：
[Feng, Shengyang; Wang, Shuyun; Li, Xiangyang; Chen, Zhi] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
通讯机构：
School of Environmental Protection and Safety Engineering, University of South China, Hengyang, China
关键词：
Aeolian soils;Confining pressure;Damping ratio;Dynamic shear modulus
摘要：
Dynamic shear modulus and damping ratio are two main parameters for describing the dynamic performance of aeolian soils. This paper presents the influence of the confining pressure, the consolidation ratio and the vibration frequency on the dynamic shear modulus and the damping ratio of aeolian soils with a series of dynamic triaxial tests. Experimental results show that the dynamic shear modulus of aeolian soils increases with the confining pressure and the consolidation ratio, while the damping ratio decreasing with them;both of the dynamic shear modulus and the consolidation ratio increases with the vibration frequency, but the influence is less than that of the confining pressure and the consolidation ratio. ©2015 ejge.
语种：
英文
展开
Numerical studies of electron cyclotron wave current drive on HL-2A tokamak
作者：
Li, J. C.* ;Gong, X. Y.;Dong, J. Q.;Zheng, P. W.;Song, S. D.;...
期刊：
PHYSICS OF PLASMAS ,2015年22(6):062512 ISSN：1070-664X
通讯作者：
Li, J. C.
作者机构：
[Li, J. C.; Gong, X. Y.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Gao, Q. D.; Song, S. D.; Dong, J. Q.] Southwestern Inst Phys, Chengdu 610041, Peoples R China.;[Zheng, P. W.] Univ South China, Sch Environm Protect & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Du, D.] Univ South China, Sch Math & Phys, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Li, J. C.] U;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.
关键词：
Fokker-Planck equation;numerical analysis;plasma density;plasma radiofrequency heating;plasma simulation;plasma temperature;plasma toroidal confinement;ray tracing;Tokamak devices
摘要：
The electron cyclotron wave (ECW) current drive (CD) for the HL-2A tokamak is investigated numerically with a new ray-tracing and Fokker-Planck code. The code is benchmarked with other well-tested linear and quasilinear codes and is then used to study the electron cyclotron current drive on the HL-2A tokamak. The wave propagation, power deposition, and driven-current profiles are presented. The effect of electron trapping is also assessed. It is found that quasilinear effects are negligible at the present ECW power levels and that when both waves are injected at an angle of 20° on the plasma equatorial plane, the CD efficiency for the HL-2A saturates at ∼0.029 × 1020 A/W/m2 and ∼0.020 × 1020 A/W/m2 for the 0.5 MW/68 GHz first harmonic ordinary (O1) and 1 MW/140 GHz second harmonic extraordinary (X2) modes, respectively. The effects of the plasma density, temperature, and wave-launching position on the driven current are also investigated analytically and numerically.
语种：
英文
展开
