浅析工科研究生科研创新能力培养
作者：
王红强;邓启湘;张晓文
期刊：
文学教育(中) ,2020年(8):144-145 ISSN：1672-3996
作者机构：
南华大学资源环境与安全工程学院;南华大学图书馆;[邓启湘; 王红强] 南华大学
关键词：
研究生;创新能力;工科院校
摘要：
科研创新能力是衡量研究生教育质量的重要方面之一.本文针对工科研究生科研创新能力培养中存在的不足,提出了从课程设置改革、导师团队建设和加强科研实践三个方面探索研究生科研创新能力培养,以期为我国工科研究生培养模式改革提供借鉴.
语种：
中文
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某铀矿地质勘探设施退役治理覆土试验研究
作者：
王文博;张晓文;李录峰
期刊：
西部资源 ,2020年(02):71-74 ISSN：1672-562X
作者机构：
南华大学资源环境与安全工程学院,衡阳421001;核工业二〇八大队,包头014010
关键词：
铀;废石堆;覆土;氡析出率;氡扩散系数;γ辐射剂量率
摘要：
铀矿地质勘探设施退役后,其放射性核素已通过多种途径进入环境,存在较大的环境影响及人身安全隐患,因此对其进行退役治理是势在必行。本文以西北地区某典型的铀矿地质勘探遗留的废石堆为研究对象,以砂质亚粘土作为覆盖材料,进行了相关覆土试验。主要研究了覆土厚度与氡析出率和γ辐射剂量率的变化关系;覆土压实度与氡扩散系数的变化关系。试验结果表明:本试验场地作为有限制开放场所的最佳覆土厚度为68cm,而作为无限制开放场所的最佳覆盖厚度不小于110cm;γ辐射剂量率随着覆土厚度的增大而急剧减小,在覆土厚度达到45cm时趋于稳定;氡扩散系数随着压实度的增大而减小;覆土厚度与氡析出率的关系符合。
语种：
中文
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田湾核电站附近某校环境辐射状况调查
作者：
陈辛;黄倩文;张晓文
期刊：
科技视界 ,2020年(17):266-268 ISSN：2095-2457
作者机构：
连云港环境辐射监测站 连云港 222000;南华大学<环境与安全工程学院> 衡阳 421001;[陈辛] 连云港环境辐射监测站;[张晓文; 黄倩文] 南华大学
关键词：
环境辐射;室内氡;γ剂量率
摘要：
核电在当今世界发展迅速,核电站正常生产时对周围环境产生的辐射让一些人产生了担忧.本文选取距田湾核电站27公里的某校园作为调查对象,采用半导体探测器和塑料闪烁体探测器对校园室内氡浓度和室外γ剂量率进行了测量与分析.结果表明:室内氡浓度与房龄有关,与建筑的类型、湿度、温度无关,房龄越大室内氡浓度越低;γ剂量率水平受地面材质和周围建筑物分布影响较大,石板砖、水泥地面周围γ剂量率水平较高,橡胶和草皮地面γ剂量率水平较低,建筑物越密集γ剂量率水平越高;校园室内氡浓度和γ剂量率水平都低于国家安全标准.
语种：
中文
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Numerical investigation on the influence of ventilation shaft on gaseous radionuclide diffusion of uranic exhaust in atmosphere
作者：
Yang, Rong;Zhang, Xiaowen* ;Zhong, Yongming;Ye, Yongjun
期刊：
Indoor and Built Environment ,2019年28(8):1031-1037 ISSN：1420-326X
通讯作者：
Zhang, Xiaowen
作者机构：
[Zhong, Yongming; Yang, Rong; Ye, Yongjun; Zhang, Xiaowen] Univ South China, Sch Environm & Safety Engn, Key Lab Radioact Waste Treatment & Disposal, Hengyang, Peoples R China.;[Zhang, Xiaowen] Univ South China, Key Lab Radioact Waste Treatment & Disposal, Changsheng West Rd 28, Hengyang 421001, Peoples R China.
通讯机构：
[Zhang, Xiaowen] U;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Changsheng West Rd 28, Hengyang 421001, Peoples R China.
关键词：
Uranium mine;Exhaust ventilation shaft;Radionuclide activity;Concentration distribution;Numerical simulation
摘要：
Understanding the distribution of radionuclides from uranium mine tail gas into the surface atmosphere is one way of dealing with radioactive pollution, but the factors affecting the concentration distribution are considered insufficiently studied. This article looks into the structural characteristics of the exhaust shaft of a uranium mine and studied the effect of the cross-sectional shape (square or round) on radionuclide concentrations. We used numerical simulation to verify the significance and clarity of the impact. The results show that, without considering the terrain, the radionuclide concentration distribution is not sensitive to wind direction at different heights, regardless of exhaust shaft shape. There are 2–5 times more radionuclides discharged from the round exhaust shaft as the square shaft, and the difference increases with height. The concentration exceeds the maximum dose requirement until approximately 500 m downwind when the square exhaust shaft is used, while it is at least 1000 m with the round exhaust shaft. These conclusions imply that the structural features of the exhaust shafts, especially the cross-sectional shape, should be given high priority during construction, and the structure of the exhaust shafts should not be neglected or oversimplified in the study of similar problems. © The Author(s) 2018.
语种：
英文
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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：
<jats:p> 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<jats:sub>2</jats:sub> adsorption–desorption experiments using the Brunauer–Emmett–Teller to be 81.86 m<jats:sup>2</jats:sup>/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. </jats:p>
语种：
英文
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三苯基膦功能化纤维状硅球的设计制备及其对ReO4-的选择性吸附
作者：
刘康;袁立永;张晓文;石伟群
作者机构：
中国科学院高能物理研究所 北京 100049;南华大学资源环境与安全工程学院 衡阳 421001
会议名称：
中国化学会第十届全国无机化学学术会议
会议时间：
2019-08-01
会议地点：
济南
会议论文集名称：
中国化学会第十届全国无机化学学术会议论文集
关键词：
三苯基膦;纤维状硅球;高铼酸根;吸附
摘要：
锝(99Tc)是乏燃料中重要的放射性元素之一,通常以易溶于水的高锝酸根（TcO4-）形式存在,在环境中迁移性极强,对生态环境和人类健康具有潜在威胁。铼（Re）与锝（Tc）的核外电子排布相同,化学性质相似,在水溶液中一般以MO4-的形式存在。常规研究中通常采用非放射性铼（Re）代替放射性锝（Tc）进行实验以避免放射性操作带来的不便,因此设计制备高效高选择性的Re O4-吸附剂意义重大。二氧化硅纳米颗粒具有稳定性好、易修饰、成本低和对环境友好等特点,在放射性核素的吸附分离方面已有较多研究[1, 2]。相较于传统二氧化硅纳米颗粒,纤维状硅球（DFNS）又具有比表面积大、有开放型孔道等优点,在制备高效、环保型放射性核素吸附剂的应用中是一种良好的无机载体。由于已有研究表明疏水性环境更有利于ReO4-的选择性吸附[3],因此通过在硅基材料表面接枝三苯基膦,增加其呈疏水性,有可能促进其对ReO4-的高效选择性吸附分离。本文采用后接枝法合成了三苯基膦功能化纤维状硅球（DFNS-P）,使用扫描电子显微镜（SEM）对硅球形貌进行了表征（图1a）,并研究了酸性条件下DFNS-P对ReO4-的吸附行为。研究结果表明DFNS-P对ReO4-具有良好的的吸附效果。4 mg DFNS-P在浓度为100 ppm、pH值为4的高铼酸铵（NH4ReO4-）溶液中能够在40 s内对ReO4-达到最大吸附量71mg/g（图1b）,这种快速吸附平衡可能与其开放型孔道特性有关;选择性实验结果表明,相同浓度的Cl-及NO3-对ReO4-的吸附几乎不产生影响（图1c）。本工作展现了功能性多孔硅材料在ReO4-等阴离子去除中的巨大应用潜力,系统工作还在开展当中。
语种：
中文
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生物炭对荒漠土壤的改良作用研究
作者：
陈萌萌;唐东山;张晓文;邓钦文;李景心;...
期刊：
山东化工 ,2019年48(7):217-221,224 ISSN：1008-021X
作者机构：
南华大学资源环境与安全工程学院,湖南衡阳 421001;衡阳市土壤污染控制与修复重点实验室,湖南衡阳 421001;[张晓文; 许婉冰; 陈萌萌; 唐东山; 邓钦文; 李景心] 南华大学
关键词：
生物炭;荒漠土壤;土壤肥力;保水率
摘要：
荒漠土壤具有肥力较低、保水性能差的特点,而生物炭孔隙疏松、比表面积大、稳定性高难分解,常被作为改良农田土壤的材料,可能对荒漠土壤同样具有改良效果。本文选用400℃的谷壳生物炭和锯末生物炭,设置不同的生物炭施用量,采用实验室恒温培养,研究60 d后不同处理下的荒漠土壤肥力和保水能力。实验证明,添加两种生物炭的荒漠土壤肥力均有提升。其中,添加谷壳生物炭的荒漠土壤pH值随施用量的增加降低,而添加锯末生物炭的荒漠土壤pH值随施用量的增加升高;添加两种生物炭荒漠土壤的有机碳、有效P含量均呈正相关变化,其中8%谷壳生物炭表现最好,分别为4.508%、30.74 mg·kg-1;保水率随生物炭施入量增加而增加。因此认为,生物炭对提高土壤肥力,增强土壤保水能力有积极作用。
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 (K-d), 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. (C) 2019 Published by Elsevier Ltd.
语种：
英文
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铀浓缩厂放射性废物管理与最小化实践
作者：
肖建华;张晓文;杨蓉;杜仁铠;张德
期刊：
辐射防护 ,2019年39(1):61-66 ISSN：1000-8187
作者机构：
南华大学环境与安全工程学院,湖南衡阳421001;中核陕西铀浓缩有限公司,陕西汉中723312;南华大学环境与安全工程学院,湖南衡阳,421001;[张德; 张晓文; 杨蓉; 肖建华; 杜仁铠] 南华大学
关键词：
铀浓缩厂;放射性废物;废物最小化;清洁解控
摘要：
介绍了某铀浓缩厂含铀放射性废物管理现状及放射性废物最小化方面的应用实践。放射性废物分类收集,集中处置,减少放射性废物的体积及产生量是基本要求。采用5%的Na2CO3和30%H2O2混合液以及清水对放射性污染管道、阀门等进行清洗,使α表面污染≤0.4 Bq/cm2,清洗液厂内循环利用。通过除锈清洗液再利用、水压试验水再利用及容器清洗工艺优化改进等措施,单台容器平均废液产生量减少35%左右,从源头上控制了含铀废液的产生量。小容器处理工艺由湿法改为干法,废水产生量减少了90%;大容器清洗过程中,除锈液可重复利用5次,可使得除锈废液的产生量减少80%左右。提高吸附尾液循环利用比,减少了废水的产生量。采用钙盐联合沉淀法处理废水,废渣年产生量平均减少20%,废水处理合格率大大提高。在此基础上,介绍了实现含铀放射性废物最小化的几点思路,并提出相关措施。
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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以MnFe_2O_4为阻挡层的Ni - YSZ 阳极支撑SOFC 的效能
作者：
吴晓燕;谭维;罗才武;张晓文;李密;...
期刊：
材料导报 ,2019年33(12):1949-1954 ISSN：1005-023X
作者机构：
南华大学资源环境与安全工程学院,衡阳,421001;南华大学研究生院,衡阳,421001;[罗才武; 张晓文; 李密; 吴晓燕; 房琦; 谭维; 谭文发] 南华大学
关键词：
固体氧化物燃料电池;阳极;阻挡层;铁酸锰;生物质气;积碳
摘要：
为提高镍-氧化钇稳定氧化锆(Ni-YSZ)阳极支撑的固体氧化物燃料电池(SOFC)以含碳气为燃料时的抗积碳性能,采用丝网印刷法在Ni-YSZ阳极表面印制阻挡层,阻挡层的材料为高温煅烧制备的铁酸锰(MnFe_2O_4)粉体。在750 ℃下以模拟污泥微波热解生物质气为燃料,测试含阻挡层的电池的电化学效能和抗积碳性能,并利用扫描电镜对测试前、后的阳极进行表征。研究结果表明:MnFe_2O_4阻挡层与Ni-YSZ 阳极的结合性较好;在Ni-YSZ 阳极上添加MnFe_2O_4阻挡层后,电池的放电性能有所降低,但是电池在以模拟生物质气为燃料时的抗积碳性能大幅提高,且在浆料中添加16%(质量分数)的石墨制备的阻挡层效果最佳。本研究对Ni-YSZ 阳极以生物质气为燃料时的抗积碳能力的改进与发展具有积极意义。
语种：
中文
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某尾矿库附近各土壤层对U(VI)的吸附特性
作者：
杨升;张晓文;张利江;吴晓燕;李密;...
期刊：
环境工程学报 ,2019年13(10):2511-2520 ISSN：1673-9108
通讯作者：
Zhang, X.
作者机构：
[张利江; 黄倩文; 杨升] School of Resource & Environmental and Safety Engineering, University of South China, Hengyang, 421001, China;Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China;[王亮] Hengyang Valin Steel Tube Co. Ltd., Hengyang, 421001, China;[张晓文; 李密; 吴晓燕] School of Resource & Environmental and Safety Engineering, University of South China, Hengyang, 421001, China, Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China
通讯机构：
[Zhang, X.] S;School of Resource & Environmental and Safety Engineering, China
关键词：
近地表处置;铀尾矿库;土壤剖面;静态吸附
摘要：
针对南方某铀尾矿库附近棕红壤剖面中的淋溶层、淀积层和母质层等土层对铀的吸附机理和空间分布规律进行了探讨。采用比表面测定、X射线荧光、扫描电镜、傅里叶变换和X射线衍射等方法对各土层样的理化性质、结构和形貌进行了表征分析;采用静态吸附法考查了时间、U(VI)初始浓度、pH、温度、粒径等因素对各土层吸附U(VI)的影响;并使用热力学和动力学方程对吸附过程进行了模拟分析。结果表明,25℃下淋溶层和淀积层pH均为6.2、母质层pH为4.1时,其对U(VI)最大吸附量分别可达23.60、22.82和13.05 mg·g~(-1)。热力学和动力学拟合结果分别表明,各土层对U(VI)更符合Langmuir方程(R~2>0.999)和准二级动力学模型(R~2>0.98)。风化程度,Fe、Mn、Al、Ca等元素及有机质含量,pH和土壤粒径等因素是各土层对U(VI)吸附能力不同的主要原因;同时,外源铀进入土壤剖面后,大部分聚集在土壤表层,随着深度的下降的铀含量也逐渐降低。研究结果可为土壤剖面中的铀和其他重金属的污染防治提供参考。
语种：
中文
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磁化夏威夷果壳活性炭制备及对U(Ⅵ)吸附机理研究
作者：
杨升;张晓文;何鹏;宋佳芹
期刊：
安徽农学通报 ,2019年25(8):125-130,132 ISSN：1007-7731
作者机构：
南华大学放射性三废处理与处置重点实验室;南华大学资源环境与安全工程学院;[宋佳芹] 湖南电子科技职业学院;[张晓文; 杨升; 何鹏] 南华大学
关键词：
夏威夷果壳活性炭;除铀;磁化;吸附
摘要：
实验选用KOH、Fe3O4纳米粒子制备磁性夏威夷果壳活性炭,并从磁化活性炭(M-AC)的改性机理、除铀(U)机理、最佳使用条件对磁性夏威夷果壳活性炭除U进行分析。结果表明:磁性活性炭在pH为5时对U去除效率最好,反应140 min后达到吸附平衡,最大吸附量为9.63 mg·g^-1,去除率可达94.6%。同时实验制备的M-AC在循环实验5次后对U(Ⅵ)去除率仍能达到91%,具有明显的磁选回收再利用能力。吸附等温模型表明吸附过程为单层吸附和多层吸附并存,热力学分析显示吸附过程属于吸热反应,动力学拟合结果则说明吸附过程以化学吸附为主,物理吸附为辅。SEM-EDS、FT-IR、XPS等表征结果进一步说明,由于M-AC在制备、活化过程中增加了醚基、羰基、羧基含量,同时比表面积上升,使得对U(Ⅵ)吸附的有效吸附面积和吸附官能团位点显著增加,提高了普通生物炭的吸附能力。磁性夏威夷果壳活性炭的制备与吸附研究,对于果壳等废料应用提供一种新的思路。
语种：
中文
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Geochronology, Petrology, and Genesis of Two Granitic Plutons of the Xianghualing Ore Field in South Hunan Province: Constraints from Zircon U–Pb Dating, Geochemistry, and Lu–Hf Isotopic Compositions
作者：
Yang, Lizhi;Wu, Xiangbin* ;Cao, Jingya* ;Hu, Bin;Zhang, Xiaowen;...
期刊：
Minerals ,2018年8(5):213- ISSN：2075-163X
通讯作者：
Wu, Xiangbin;Cao, Jingya
作者机构：
[Hu, Bin; Wu, Xiangbin; Yang, Lizhi] Cent S Univ, Key Lab Metallogen Predict Nonferrous Met & Geol, Minist Educ, 932 Lushan Rd, Changsha 410083, Hunan, Peoples R China.;[Cao, Jingya] Univ Sci & Technol China, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Anhui, Peoples R China.;[Zhang, Xiaowen] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Gong, Yushuang] Sinomine Resource Explorat Co Ltd, Beijing 100089, Peoples R China.;[Liu, Weidong] 7 Inst Geol & Mineral Explorat Shandong Prov, Linyi 276006, Peoples R China.
通讯机构：
[Wu, Xiangbin] C;[Cao, Jingya] U;Cent S Univ, Key Lab Metallogen Predict Nonferrous Met & Geol, Minist Educ, 932 Lushan Rd, Changsha 410083, Hunan, Peoples R China.;Univ Sci & Technol China, CAS Key Lab Crust Mantle Mat & Environm, Hefei 230026, Anhui, Peoples R China.
关键词：
zircon U-Pb dating;geochemistry;Lu-Hf isotopes;Xianghualing;South Hunan
摘要：
Two small-sized granitic plutons, outcropped in Xianghualing ore field, South Hunan (South China), have a close relationship with the super large-scale Sn–W polymetallic mineralization in this ore field. The Laiziling and Jianfengling plutons are composed of medium- to coarse-grained two-mica and coarse-grained biotite granites, respectively, and have zircon U–Pb ages of 156.4 ± 1.4 Ma and 165.2 ± 1.4 Ma, respectively. Both of the Laiziling and Jianfengling granites are characterized by extremely similar elemental and Lu–Hf isotopic compositions with high contents of SiO2, Al2O3, Na2O, K2O, high A/CNK ratios, negative ""Hf(t) values (ranging from -3.86 to -1.38 and from -5.44 to -3.71, respectively), and old TDMC ages (ranging from 1.30 to 1.47 Ga and from 1.32 to 1.56 Ga, respectively). These features indicate that they both belong to highly fractionated A-type granites, and were formed in an extensional setting and from the same magma chamber originated from the Paleoproterozoic metamorphic basement of South China with a certain amount of mantle-derived magma involved with temperatures of ca. 730 ºC and low oxygen fugacity. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.
语种：
英文
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Uranium Extraction from Tailings by Dilute Alkali Pretreatment-Sulfuric Acid Leaching Technology
作者：
Huang, Chunmei;Li, Mi* ;Zhang, Xiaowen;Gao, Fangying;Wu, Xiaoyan;...
期刊：
JOM ,2018年70(11):2746-2752 ISSN：1047-4838
通讯作者：
Li, Mi
作者机构：
[Li, Mi; Gao, Fangying; Fang, Qi; Huang, Chunmei; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan; Zhang, De] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Li, Mi; Fang, Qi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiaoyan; Zhang, De] 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 Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;Univ South China, Key Lab Radioact Waste Treatment & Disposal, Hengyang 421001, Peoples R China.
摘要：
Preliminary extraction research was carried out to develop a suitable dilute alkali pretreatment–sulfuric acid leaching process for uranium recovery from tailings containing 80 ppm uranium. The effects of alkali concentration, liquid-to-solid ratio, stirring speed and leaching time on uranium content in the leaching residues were investigated. The results showed that the leaching efficiency of dilute alkali pretreatment–sulfuric acid leaching is superior to direct acid leaching. Only 13 ppm and 7.5 ppm of uranium remained in tailings by using NaOH and Na 2 CO 3 , respectively, with an alkali concentration of 10 g/L, a liquid-to-solid ratio of 20, and an agitation of 400 rpm for 2 h. In addition, uranium liberation was significantly promoted by forming pores during the leaching process. This technology has advantages of low energy consumption, high leaching efficiency and less impurity production compared to traditional direct acid leaching. © 2018, The Minerals, Metals & Materials Society.
语种：
英文
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水稻秸秆生物炭对水中Pb2＋的吸附性能和机理研究
作者：
彭莹;张晓文;张宇;郑超文;吴苏煌;...
期刊：
环保科技 ,2017年23(6):1-5 ISSN：1674-0254
作者机构：
南华大学环境与安全工程学院,湖南衡阳,421001;[吴苏煌; 张晓文; 向杨; 郑超文; 张宇; 彭莹] 南华大学
关键词：
生物炭;铅;水稻秸秆;热力学;化学吸附
摘要：
利用比表面积分析仪（ BET ）、 X 射线光电子能谱仪（ X P S ）研究了水稻秸秆生物炭的结构 与性质,考察了吸附时间、固液比、 pH 等因素对生物炭吸附性能的影响,并探讨了生物炭材料对 Pb2＋的吸附机理.结果表明：水溶液的pH 值是影响生物炭吸附能力的关键因素;吸附过程符合准 二次动力学方程,等温吸附过程符合Langmuii？方程式,并且通过Langmuii？方程式求出其最大吸附 量高达60. 57 mg/g ;水稻秸秆生物炭对P b2 ＋吸附是以化学吸附为主.
语种：
中文
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从低品位铀尾矿中氧化浸出铀
作者：
李密;张彪;张晓文;黄婧;丁德馨;...
期刊：
中国有色金属学报 ,2017年27(1):145-154 ISSN：1004-0609
通讯作者：
Ding, De-Xin(dingdxzzz@163.com)
作者机构：
[张晓文; 李密; 张彪; 黄婧] School of Environment Protection and Safety Engineering, University of South China, Hengyang, 421001, China;[张晓文; 李密] Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China;[丁德馨; 叶勇军] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, China
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：
铀尾矿;浸出;氧化;脉石
摘要：
针对低品位铀尾矿因脉石含量高、物相赋存状态复杂而造成的铀浸出率低的问题,提出添加辅助氧化剂破坏脉石结构而实现强化浸出铀的思路。采用单因素实验法对比常规酸浸和3种氧化剂(H_2O_2、MnO_2和Fe~(3+))强化酸浸对铀浸出率的影响。结果表明:当浸出温度、硫酸浓度和液固比分别为30 ℃、1 mol/L和20:1时,采用常规酸浸6 h后铀的浸出率仅为78%,而在相同的浸出条件下,强化酸浸1.5 h铀的浸出率可达到95%。浸出渣的XRD及SEM-EDS分析结果表明,H_2O_2及MnO_2均能破坏脉石晶体结构,减少颗粒团聚,但添加MnO_2后生成新的硅酸锰盐晶体,Fe~(3+)不能破坏脉石结构,但其氧化作用在一定程度上能加快铀的浸出。
语种：
中文
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掺杂氧化铋混凝土的辐射屏蔽效果研究及其优化
作者：
张晓文;姚娅;易成;李密;杨蓉;...
期刊：
核技术 ,2017年40(6):21-26 ISSN：0253-3219
作者机构：
南华大学放射性三废处理与处置重点实验室 衡阳 421001;南华大学环境保护与安全工程学院 衡阳 421001;万马联合控股集团有限公司 杭州 310018;[姚娅; 杨升; 杨蓉; 蒋天娇] School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China;[李密; 张晓文] Key Laboratory of Radioactive Waste Treatment and Disposal, University of South China, Hengyang, 421001, China, School of Environmental Protection and Safety Engineering, University of South China, Hengyang, 421001, China
关键词：
氧化铋;混凝土;线衰减系数;田口法
摘要：
将氧化铋以粉末形式添加到普通混凝土中,制备出绿色无污染且具有良好的?射线屏蔽性能的掺杂氧化铋的混凝土。相较于普通混凝土,氧化铋-混凝土的屏蔽性能及力学性能均得到改善。对比屏蔽性能实验结果及MCNP5（Monte Carlo N-Particle 5）模拟结果,二者相符很好,可以用MCNP5进行后期配合比设计优化。运用田口方法对水泥量、水胶比、氧化铋比例及砂率等进行优化设计。结果表明,对氧化铋-混凝土屏蔽能力影响最大的参数是氧化铋的加入量,其次为水泥量,水胶比及砂率的影响可忽略。
语种：
中文
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Extraction of uranium from tailings by sulfuric acid leaching with oxidants
作者：
Huang, Jing;Li, Mi* ;Zhang, Xiaowen;Huang, Chunmei;Wu, Xiaoyan
期刊：
IOP Conference Series: Earth and Environmental Science ,2017年69(1):012050 ISSN：1755-1307
通讯作者：
Li, Mi
作者机构：
[Li, Mi; Huang, Jing; Zhang, Xiaowen; Huang, Chunmei; Wu, Xiaoyan] 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.
会议名称：
3rd International Conference on Advances in Energy, Environment and Chemical Engineering (AEECE)
会议时间：
MAY 26-28, 2017
会议地点：
Chengdu, PEOPLES R CHINA
会议主办单位：
[Huang, Jing;Li, Mi;Zhang, Xiaowen;Huang, Chunmei;Wu, Xiaoyan] 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.
会议论文集名称：
IOP Conference Series-Earth and Environmental Science
关键词：
Chemical reactions;Extraction;Leaching;Minerals;Oxidants;Sulfur determination;Sulfuric acid;Uranium metallurgy;Acid concentrations;Dilute acids;Leaching process;Optimum reaction conditions;Reaction temperature;Sulfuric acid leaching;Technological mineralogies;Uranium
摘要：
Recovery of uranium have been performed by leaching uranium-containing tailings in sulfuric acid system with the assistance of HF, HClO4, H2O2 and MnO2. The effect of reagent dosage, sulfuric acid concentration, Liquid/solid ratio, reaction temperature and particle size on the leaching of uranium were investigated. The results show that addiction of HF, HClO4, H2O2 and MnO2 significantly increased the extraction of uranium under 1M sulphuric acid condition and under the optimum reaction conditions a dissolution fraction of 85% by HClO4, 90% by HF, 95% by H2O2 can be reached respectively. The variation of technological mineralogy properites of tailings during leaching process show that the assistants can break gangue effectively. These observations suggest that optimum oxidants could potentially influence the extraction of uranium from tailings even under dilute acid condition. © Published under licence by IOP Publishing Ltd.
语种：
英文
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Optimization of demulsification-coagulation-adsorption parameters for the treatment of wastewater with fluorescent permeating agent from a Chinese machinery plant
作者：
Zhang, Xiaowen* ;Wang, Beibei* ;Wu, Xiao Yan;Li, Mi;Tan, Wenfa
期刊：
Desalination and Water Treatment ,2017年100:46-54 ISSN：1944-3994
通讯作者：
Zhang, Xiaowen;Wang, Beibei
作者机构：
[Li, Mi; Zhang, Xiaowen; Tan, Wenfa; Wu, Xiao Yan; Wang, Beibei] Univ South China, Sch Environm & Safety Engn, Hengyang, Hunan, Peoples R China.
通讯机构：
[Zhang, XW; Wang, BB] U;Univ South China, Sch Environm & Safety Engn, Hengyang, Hunan, Peoples R China.
关键词：
Demulsification-coagulation-adsorbtion;Emulsifying wastewater;Fluorescent penetrant
摘要：
Fluorescent penetrant is used for the cleaning process of precision machine parts in non-destruc-tive testing (NDT). Wastewater will be produced in that course with high chemical oxygen demand (COD) (1000–15,000 mg/L), high mineral oil (300–3000 mg/L) and high chroma (600–2000). This liquid waste has a serious influence on the environment due to its’ stronger biological toxicity and higher virulence. When the oil content exceeds 0.01 mg/L in water, the water will lack oxygen and lead aquatic plants and animals to die, thus create badly water pollution. How to treat this polluted water is a difficult task in sewage treatment. The demulsification-coagulation-adsorption process was adapted for conducting this emulsifying wastewater. This research has compared the demulsification effects between the nonionic surfactant demulsifier of AR and the electrolyte demulsifier of CaCl2 and MgCl2 as well as the coagulation performance between the polymeric aluminum chloride (PAC) and the polyaluminium chloride sulfate (PACS). Effects of the types of demulsifier and coagulant, dosage, pH, static duration, absorbing time and other process parameters have been investigated. Based on this, the process parameters have been optimized. The results shown that the best treatment condition was using AR as demulsifier, PACS as flocculant, and vermiculite as adsorbent, which resulted in higher quality and efficiency in removal of 97.87% COD, 99.62% oil and 99.22% colority. This could meet the first grade standard of the national integrated wastewater discharge standard (GB8978-1996). Thus, the integration method of demulsification-coagulation-adsorbtion is a practicable way to solve this kind of sewage. © 2017 Desalination Publications. All rights reserved.
语种：
英文
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