Preparation of ethylenediamine-modified magnetic chitosan complex for adsorption of uranyl ions
作者：
Wang, Jing-song* ;Peng, Rui-ting;Yang, Jin-hui;Liu, Yao-chi;Hu, Xin-jiang
期刊：
Carbohydrate Polymers ,2011年84(3):1169-1175 ISSN：0144-8617
通讯作者：
Wang, Jing-song
作者机构：
[Wang, Jing-song; Peng, Rui-ting; Yang, Jin-hui] Univ S China, Sch Urban Construct, Hengyang 421001, Hunan, Peoples R China.;[Wang, Jing-song; Peng, Rui-ting; Yang, Jin-hui] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Liu, Yao-chi] Cent S Univ, Sch Chem & Chem Engn, Changsha 410083, Hunan, Peoples R China.;[Hu, Xin-jiang] Hunan Univ, Coll Environm Sci & Engn, Changsha 410082, Hunan, Peoples R China.
通讯机构：
[Wang, Jing-song] Univ S China, Sch Urban Construct, Hengyang 421001, Hunan, Peoples R China.
关键词：
Chitosan<&wdkj&>Magnetic<&wdkj&>Modified<&wdkj&>Uranyl ions<&wdkj&>Adsorption
摘要：
Ethylenediamine-modified magnetic chitosan (EMMC) complex was developed as a novel magnetic adsorbent for the removal of uranyl ions. XRD spectrum indicated that the magnetic particles were pure Fe<inf>3</inf>O<inf>4</inf> with a spinel structure, and the binding of chitosan did not result in a phase change. IR analysis demonstrated that Fe<inf>3</inf>O<inf>4</inf> particles were successfully bounded by chitosan and more amino groups appeared in the EMMC samples. EMMC was found to be quite efficient to adsorb uranyl ions at pH 2-7. Equilibrium was established within 30 min, and the kinetic experimental data properly correlated with the pseudo-second-order kinetic model, indicating that the chemical sorption is the rate-limiting step. The adsorption data could be best interpreted by the Sips model with a maximum adsorption capacity of 82.83 mg U g<sup>-1</sup>. The EMMC can be regenerated with high efficiency, suggesting that this adsorbent is satisfactory to reuse uranyl ions. ©2011 Elsevier Ltd. All rights reserved.
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英文
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Crack propagation and coalescence of brittle rock-like specimens with pre-existing cracks in compression
作者：
Cao, Ping;Liu, Taoying* ;Pu, Chengzhi;Lin, Hang
期刊：
Engineering Geology ,2015年187:113-121 ISSN：0013-7952
通讯作者：
Liu, Taoying
作者机构：
[Lin, Hang; Liu, Taoying; Cao, Ping; Pu, Chengzhi] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.;[Liu, Taoying; Pu, Chengzhi] Univ South China, Nucl Resource Coll Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Liu, Taoying] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
Rock-like material<&wdkj&>Multiple pre-existing flaws<&wdkj&>Crack propagation and coalescence<&wdkj&>Uniaxial compression
摘要：
Fracture coalescence, which plays an important role in the behavior of brittle materials, is investigated by loading rock-like specimens with two and three pre-existing flaws made by pulling out the embedded metal inserts in the pre-cured period. Different geometries are obtained by changing the angle of the flaws with respect to the direction of loading and the spacing. With reference to the experimental observation of crack initiation and propagation from pre-existing flaws, the influences of the third pre-existing flaw on the cracking processes was analyzed. It was found during the test that: with the increase of the angle of the rock bridge, the rock specimen takes a turn from wing crack propagation failure to crack coalescence failure, and it will be more obvious with the increase of the prefabricated crack angle. According to the different geometries of pre-existing cracks, seven types of coalescence have been identified based on the nature of the cracks for the specimen with two pre-existing flaws. The multi-crack interaction results in the continuous degradation of the macroscopic mechanical properties of the rock mass. On one hand, it weakens the trend of relative sliding of the coplanar cracks, and on the other hand, it changed the coalescence patterns of the fractured specimen. The research reported here provides increased understanding of the fundamental nature of rock mass failure in compression. (C) 2014 Elsevier B.V. All rights reserved.
语种：
英文
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Fatigue damage variable and evolution of rock subjected to cyclic loading
作者：
Xiao, Jian-Qing;Ding, De-Xin* ;Jiang, Fu-Liang;Xu, Gen
期刊：
International Journal of Rock Mechanics and Mining Sciences ,2010年47(3):461-468 ISSN：1365-1609
通讯作者：
Ding, De-Xin
作者机构：
[Jiang, Fu-Liang; Xiao, Jian-Qing; Ding, De-Xin] Univ S China, Sch Nucl Resources & Nucl Fuel Engn, Hengyang 421001, Peoples R China.;[Xiao, Jian-Qing] Chinese Acad Sci, Inst Rock & Soil Mech, State Key Lab Geomech & Geotech Engn, Wuhan 430071, Peoples R China.;[Xu, Gen; Jiang, Fu-Liang; Xiao, Jian-Qing] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.
通讯机构：
[Ding, De-Xin] Univ S China, Sch Nucl Resources & Nucl Fuel Engn, Hengyang 421001, Peoples R China.
语种：
英文
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Cracking and Stress–Strain Behavior of Rock-Like Material Containing Two Flaws Under Uniaxial Compression
作者：
Zhao, Yanlin;Zhang, Lianyang* ;Wang, Weijun;Pu, Chengzhi;Wan, Wen;Tang, Jingzhou
期刊：
Rock Mechanics and Rock Engineering ,2016年49(7):2665-2687 ISSN：0723-2632
通讯作者：
Zhang, Lianyang
作者机构：
[Wang, Weijun; Tang, Jingzhou; Zhao, Yanlin; Wan, Wen] Hunan Univ Sci & Technol, Sch Energy & Safety Engn, Hunan Prov Key Lab Safe Min Tech Coal Mines, Xiangtan 411201, Hunan, Peoples R China.;[Zhao, Yanlin] China Univ Min & Technol, State Key Lab Coal Resources & Safety Min, Xuzhou 221008, Jiangsu, Peoples R China.;[Zhang, Lianyang] Univ Arizona, Dept Civil Engn & Engn Mech, Tucson, AZ 85721 USA.;[Pu, Chengzhi] Univ South China, Nucl Resources Engn Coll, Heng Yang 421001, Hunan, Peoples R China.
通讯机构：
[Zhang, Lianyang] Univ Arizona, Dept Civil Engn & Engn Mech, Tucson, AZ 85721 USA.
关键词：
Crack coalescence;Crack propagation;Flawed specimen;Strain concentration;Strain jump
摘要：
This paper investigates the cracking and stress–strain behavior, especially the local strain concentration near the flaw tips, of rock-like material containing two flaws. A series of uniaxial compression tests were carried out on rock-like specimens containing two flaws, with strain gauges mounted near the flaw tips to measure the local strain concentration under the uniaxial compressive loading. Four different types of cracks (wing cracks, anti-wing cracks, coplanar shear cracks and oblique shear cracks) and seven patterns of crack coalescences (T1 and T2;S1 and S2;and TS1, TS2 and TS3) are observed in the experiments. The type of crack coalescence is related to the geometry of the flaws. In general, the crack coalescence varies from the S-mode to the TS-mode and then to the T-mode with the increase of the rock bridge ligament angle. The stress–strain curves of the specimens containing two flaws are closely related to the crack development and coalescence process. The strain measurements indicate that the local tensile strain concentration below or above the pre-existing flaw tip causes wing or anti-wing cracks, while the local compressive strain concentration near the flaw tip is related to the shear crack. The measured local tensile strain shows a jump at the initiation of wing- and anti-wing cracks, reflecting the instant opening of the wing- and anti-wing crack propagating through the strain gauge. During the propagation of wing- and anti-wing cracks, the measured local tensile strain gradually increases with few jumps, implying that the opening deformation of wing- and anti-wing cracks occurs in a stable manner. The shear cracks initiate followed by a large and abrupt compressive strain jump and then quickly propagate in an unstable manner resulting in the failure of specimens. ©2016, Springer-Verlag Wien.
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英文
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Screening of Plant Species for Phytoremediation of Uranium, Thorium, Barium, Nickel, Strontium and Lead Contaminated Soils from a Uranium Mill Tailings Repository in South China
作者：
Li, Guang-yue;Hu, Nan;Ding, De-xin* ;Zheng, Ji-fang;Liu, Yu-long;Wang, Yong-dong;Nie, Xiao-qin
期刊：
Bulletin of Environmental Contamination and Toxicology ,2011年86(6):646-652 ISSN：0007-4861
通讯作者：
Ding, De-xin
作者机构：
[Li, Guang-yue; Liu, Yu-long; Nie, Xiao-qin; Hu, Nan; Zheng, Ji-fang; Ding, De-xin; Wang, Yong-dong] Univ S China, Key Discipline Lab Natl Def Biol Technol Uranium, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, De-xin] Univ S China, Key Discipline Lab Natl Def Biol Technol Uranium, Hengyang 421001, Hunan, Peoples R China.
关键词：
Uranium<&wdkj&>Thorium<&wdkj&>Hyperaccumulator<&wdkj&>Mill tailings<&wdkj&>Phytoremediation factor
摘要：
The concentrations of uranium, thorium, barium, nickel, strontium and lead in the samples of the tailings and plant species collected from a uranium mill tailings repository in South China were analyzed. Then, the removal capability of a plant for a target element was assessed. It was found that Phragmites australis had the greatest removal capabilities for uranium (820 μg), thorium (103 μg) and lead (1,870 μg). Miscanthus floridulus had the greatest removal capabilities for barium (3,730 μg) and nickel (667 μg), and Parthenocissus quinquefolia had the greatest removal capability for strontium (3,920 μg). In this study, a novel coefficient, termed as phytoremediation factor (PF), was proposed, for the first time, to assess the potential of a plant to be used in phytoremediation of a target element contaminated soil. Phragmites australis has the highest PFs for uranium (16.6), thorium (8.68), barium (10.0) and lead (10.5). Miscanthus floridulus has the highest PF for Ni (25.0). Broussonetia papyrifera and Parthenocissus quinquefolia have the relatively high PFs for strontium (28.1 and 25.4, respectively). On the basis of the definition for a hyperaccumulator, only Cyperus iria and Parthenocissus quinquefolia satisfied the criteria for hyperaccumulator of uranium (36.4 μg/g) and strontium (190 μg/g), and could be the candidates for phytoremediation of uranium and strontium contaminated soils. The results show that the PF has advantage over the hyperaccumulator in reflecting the removal capabilities of a plant for a target element, and is more adequate for assessing the potential of a plant to be used in phytoremediation than conventional method.
语种：
英文
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Inverted S-shaped model for nonlinear fatigue damage of rock
作者：
Xiao, Jian-Qing* ;Ding, De-Xin;Xu, Gen;Jiang, Fu-Liang
期刊：
International Journal of Rock Mechanics and Mining Sciences ,2009年46(3):643-648 ISSN：1365-1609
通讯作者：
Xiao, Jian-Qing
作者机构：
[Jiang, Fu-Liang; Xiao, Jian-Qing; Ding, De-Xin] Univ S China, Sch Nucl Resources & Safety Engn, Hengyang 421001, Peoples R China.;[Xu, Gen; Jiang, Fu-Liang; Xiao, Jian-Qing] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.;[Xiao, Jian-Qing] Univ S China, Sch Math & Phys, Hengyang 421001, Peoples R China.
通讯机构：
[Xiao, Jian-Qing] Univ S China, Sch Math & Phys, Hengyang 421001, Peoples R China.
语种：
英文
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Insight into the Extraction Mechanism of Americium(III) over Europium(III) with Pyridylpyrazole: A Relativistic Quantum Chemistry Study
作者：
Kong, Xiang-He;Wu, Qun-Yan;Wang, Cong-Zhi;Lan, Jian-Hui;Chai, Zhi-Fang;Nie, Chang-Ming;Shi, Wei-Qun*
期刊：
Journal of Physical Chemistry A ,2018年122(18):4499-4507 ISSN：1089-5639
通讯作者：
Shi, Wei-Qun
作者机构：
[Wu, Qun-Yan; Kong, Xiang-He; Chai, Zhi-Fang; Wang, Cong-Zhi; Lan, Jian-Hui; Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.;[Nie, Chang-Ming; Kong, Xiang-He] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.;[Chai, Zhi-Fang] Soochow Univ, Sch Radiol & Interdisciplinary Sci RAD X, Suzhou 215123, Peoples R China.;[Chai, Zhi-Fang] Soochow Univ, Collaborat Innovat Ctr Radiat Med Jiangsu Higher, Suzhou 215123, Peoples R China.
通讯机构：
[Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.
会议名称：
18th Meeting on Time-Resolved Vibrational Spectroscopy (TRVS)
会议时间：
2017
会议地点：
Cambridge, ENGLAND
会议主办单位：
[Kong, Xiang-He;Wu, Qun-Yan;Wang, Cong-Zhi;Lan, Jian-Hui;Chai, Zhi-Fang;Shi, Wei-Qun] Chinese Acad Sci, Inst High Energy Phys, Lab Nucl Energy Chem, Beijing 100049, Peoples R China.^[Kong, Xiang-He;Nie, Chang-Ming] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.^[Chai, Zhi-Fang] Soochow Univ, Sch Radiol & Interdisciplinary Sci RAD X, Suzhou 215123, Peoples R China.^[Chai, Zhi-Fang] Soochow Univ, Collaborat Innovat Ctr Radiat Med Jiangsu Higher, Suzhou 215123, Peoples R China.
摘要：
Separation of trivalent actinides (An(III)) and lanthanides (Ln(III)) is one of the most important steps in spent nuclear fuel reprocessing. However, it is very difficult and challenging to separate them due to their similar chemical properties. Recently the pyridylpyrazole ligand (PypzH) has been identified to show good separation ability toward Am(III) over Eu(III). In this work, to explore the Am(III)/Eu(III) separation mechanism of PypzH at the molecular level, the geometrical structures, bonding nature, and thermodynamic behaviors of the Am(III) and Eu(III) complexes with PypzH ligands modified by alkyl chains (Cn-PypzH, n = 2, 4, 8) have been systematically investigated using scalar relativistic density functional theory (DFT). According to the NBO (natural bonding orbital) and QTAIM (quantum theory of atoms in molecules) analyses, the M-N bonds exhibit a certain degree of covalent character, and more covalency appears in Am-N bonds compared to Eu-N bonds. Thermodynamic analyses suggest that the 1:1 extraction reaction, [M(NO<inf>3</inf>)(H<inf>2</inf>O)<inf>6</inf>]<sup>2+</sup>+ PypzH + 2NO<inf>3</inf><sup>-</sup>→M(PypzH)(NO<inf>3</inf>)<inf>3</inf>(H<inf>2</inf>O) + 5H<inf>2</inf>O, is the most suitable for Am(III)/Eu(III) separation. Furthermore, the extraction ability and the Am(III)/Eu(III) selectivity of the ligand PypzH is indeed enhanced by adding alkyl-substituted chains in agreement with experimental observations. Besides this, the nitrogen atom of pyrazole ring plays a more significant role in the extraction reactions related to Am(III)/Eu(III) separation compared to that of pyridine ring. This work could identify the mechanism of the Am(III)/Eu(III) selectivity of the ligand PypzH and provide valuable theoretical information for achieving an efficient Am(III)/Eu(III) separation process for spent nuclear fuel reprocessing.<br/> ©2018 American Chemical Society.
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英文
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Adsorption and recovery of U(vi) from low concentration uranium solution by amidoxime modified Aspergillus niger
作者：
Li, Le;Hu, Nan;Ding, Dexin* ;Xin, Xin;Wang, Yongdong;Xue, Jinhua;Zhang, Hui;Tan, Yan
期刊：
RSC Advances ,2015年5(81):65827-65839 ISSN：2046-2069
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zhang, Hui; Tan, Yan; Li, Le; Hu, Nan; Xin, Xin; Xue, Jinhua; Wang, Yongdong] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Tan, Yan; Li, Le; Xue, Jinhua] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
通讯机构：
[Ding, Dexin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
摘要：
Amidoxime modified Aspergillus niger (AMAN) was prepared by the oximation reaction. The effects of the initial pH, contact time, initial U(vi) concentration and biosorbent dose on the adsorption of U(vi) ions from radioactive wastewater in U(vi) concentrations of less than 1 mg L<sup>-1</sup>by AMAN and the raw Aspergillus niger (RAN) were investigated. The maximum adsorption efficiency by AMAN for the 0.5 mg L<sup>-1</sup>U(vi) solution amounted to 98.85% under the optimum adsorption conditions, while the maximum adsorption efficiency by RAN was only 77.83%. The adsorption equilibrium data were found to be best fitted to Langmuir isotherm model, and the maximum biosorption capacity of AMAN for U(vi) was estimated to be 621 mg g<sup>-1</sup>at 298 K. The biosorption kinetics followed the pseudo-second order model and intraparticle diffusion equation. The Gibbs free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) showed that the adsorption process of U(vi) was spontaneous, feasible and endothermic. The SEM-EDS study indicated that much more U(vi) ions were adsorbed by AMAN than by RAN. FT-IR study showed that the -NH<inf>2</inf>and =N-OH groups of amidoxime were the dominant ones for binding UO<inf>2</inf><sup>2+</sup>ions. Moreover, AMAN was found to have excellent selective adsorption capability of U(vi) due to amidoxime groups. The UO<inf>2</inf><sup>2+</sup>ions adsorbed by AMAN could be desorbed using 0.1 M HCl, and the desorption efficiency reaching 87.28% at the 8th cycle of adsorption and desorption. ©The Royal Society of Chemistry.
语种：
英文
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Influence of single flaw on the failure process and energy mechanics of rock-like material
作者：
Jin, Jin;Cao, Ping;Chen, Yu* ;Pu, Chengzhi;Mao, Dawei;Fan, Xiang
期刊：
Computers and Geotechnics ,2017年86:150-162 ISSN：0266-352X
通讯作者：
Chen, Yu
作者机构：
[Jin, Jin; Cao, Ping; Chen, Yu] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.;[Chen, Yu] China Univ Min & Technol, State Key Lab Coal Resources & Safe Min, Xuzhou 221116, Jiangsu, Peoples R China.;[Pu, Chengzhi] Univ South China, Sch Nucl Resources Engn, Hengyang 421001, Peoples R China.;[Mao, Dawei] Power China Zhongnan Engn Corp Ltd, Changsha 410014, Hunan, Peoples R China.;[Fan, Xiang] Changan Univ, Sch Highway, Xian 710064, Peoples R China.
通讯机构：
[Chen, Yu] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Hunan, Peoples R China.
关键词：
Failure pattern<&wdkj&>Micro-crack increase<&wdkj&>Particle deformation field<&wdkj&>Energy mechanism<&wdkj&>PFC
摘要：
This paper investigates the influence of a flaw on crack initiation, the failure mode, deformation field and energy mechanism of the rock-like material under uniaxial compression. The results of laboratory test and numerical simulation demonstrate the flaw inclination effect can be classified into three groups: 0-30 degrees, 30-60 degrees and 75-90 degrees. The characteristic stresses increase as the flaw angle increases. The tensile cracks initiate from gentle flaws (alpha <= 30 degrees) and shear cracks appear at tips of steep flaws (alpha >= 45 degrees). The input energy, strain energy and dissipation energy of a specimen show approximate increasing trends as the flaw angle increases. (C) 2017 Elsevier Ltd. All rights reserved.
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英文
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Three-dimensional thermoluminescence spectra of different origin quartz from Altay Orogenic belt, Xinjiang, China
作者：
Tan, Kaixuan* ;Liu, Zehua;Zeng, Sheng;Liu, Yan;Xie, Yanshi;Rieser, Uwe
期刊：
Radiation Measurements ,2009年44(5-6):529-533 ISSN：1350-4487
通讯作者：
Tan, Kaixuan
作者机构：
[Liu, Yan; Zeng, Sheng; Liu, Zehua; Xie, Yanshi; Tan, Kaixuan] Univ S China, Sch Nucl Resource & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[Rieser, Uwe] Victoria Univ Wellington, Sch Geog Environm & Earth Sci, Wellington, New Zealand.
通讯机构：
[Tan, Kaixuan] Univ S China, Sch Nucl Resource & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
会议名称：
12th International Conference on Luminescence and Electron Spin Resonance
会议时间：
SEP 18-22, 2008
会议地点：
Peking Univ, Beijing, PEOPLES R CHINA
会议主办单位：
[Tan, Kaixuan;Liu, Zehua;Zeng, Sheng;Liu, Yan;Xie, Yanshi] Univ S China, Sch Nucl Resource & Safety Engn, Hengyang 421001, Hunan, Peoples R China.^[Rieser, Uwe] Victoria Univ Wellington, Sch Geog Environm & Earth Sci, Wellington, New Zealand.
关键词：
Quartz<&wdkj&>Thermoluminescence<&wdkj&>3-D spectra<&wdkj&>Altay orogenic belt
摘要：
Three-dimensional thermoluminescence spectra are measured for different types of geological origin quartz from the Altay orogenic belt, northern Xinjiang, China. The results show striking differences which appear to be characteristic of their geological origin. Granitic quartz is dominated by emission bands at 420-430 nm, 550-560 nm, at a temperature of 170 °C. Pegmatite quartz is characterized by an intense 480 nm emission band at 170 °C. Volcanic quartz has exclusive UV (340-360 nm) and violet (410-430 nm) emission bands. Hydrothermal quartz exhibits very different TL spectral characteristics because of different hydrothermal activity and mineralization. Only one TL peaks at 485 nm/170 °C was observed in sedimentary quartz. An intense 730 nm emission band observed at 170 °C considered generally to be characteristics of feldspar was observed in quartz from granite and hydrothermal Au-bearing quartz. This TL peak is probably related to the centre of [FeO<inf>4</inf>]<sup>0</sup> on an Si site. All samples show an intense 990-1000 nm emission band at 330 °C. Identical types of quartz formed in different regions or different geological and tectonic settings can also exhibit striking differences in TL spectra. ©2009 Elsevier Ltd. All rights reserved.
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英文
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Removal and Recovery of U(VI) from Low Concentration Radioactive Wastewater by Ethylenediamine-Modified Biomass of Aspergillus niger
作者：
Ding, De Xin* ;Xin, Xin;Li, Le;Hu, Nan;Li, Guang Yue;Wang, Yong Dong;Fu, Ping Kun
期刊：
Water, Air, and Soil Pollution ,2014年225(12):2206- ISSN：0049-6979
通讯作者：
Ding, De Xin
作者机构：
[Wang, Yong Dong; Li, Guang Yue; Ding, De Xin; Hu, Nan; Xin, Xin; Fu, Ping Kun] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Li, Le] Univ South China, Sch Publ Hlth, Hengyang 421001, Peoples R China.
通讯机构：
[Ding, De Xin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词：
Aspergillus niger<&wdkj&>Ethylenediamine<&wdkj&>Biosorption<&wdkj&>Low concentration radioactive wastewater<&wdkj&>U(VI)
摘要：
In order to develop an effective and economical method for removing U(VI) from the low concentration radioactive wastewater with the U(VI) concentration of less than 1 mg L<sup>-1</sup>, the biomass of Aspergillus niger was prepared and modified with ethylenediamine, and the biosorption of uranium from the low concentration radioactive wastewater by the unmodified and the modified biomasses was investigated in a batch system. The modified biomass exhibited the adsorption efficiency of 99.25 % for uranium under the optimum conditions that pH was 5.0, the contact time was 150 min, and the biosorbent dose was 0.2 g L<sup>-1</sup>. The adsorption fitted well to Langmuir isotherm, and the maximum sorption capacity of the modified biomass for U(VI) was determined to be 6.789 mg g<sup>-1</sup> which increased by 36.45 % compared with the unmodified biomass. The adsorption kinetics was better depicted by pseudo-second-order kinetic model. The Gibbs free energy change (ΔG <sup>0</sup>), enthalpy change (ΔH <sup>0</sup>), and entropy change (ΔS <sup>0</sup>) showed that the process of U(VI) adsorption was spontaneous, endothermic, and feasible. The changes in the groups, morphology, and the presence of U(VI) on the surface of the adsorbents which were characterized by FT-IR, SEM, and EDS, demonstrated that the U(VI) was successfully adsorbed onto the modified biomass. Moreover, the UO<inf>2</inf> <sup>2+</sup> absorbed on the modified biomass can be released by 0.1 mol L<sup>-1</sup> HNO<inf>3</inf> with high desorption efficiency of 99.21 %. The results show that the modified biomass can remove U(VI) from low concentration radioactive wastewater more effectively than the unmodified biomass.
语种：
英文
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New Amidoxime-Based Material TMP-g-AO for Uranium Adsorption under Seawater Conditions
作者：
Zeng, Jiayun;Zhang, Hui;Sui, Yang;Hu, Nan;Ding, Dexin* ;Wang, Fang;Xue, Jinhua;Wang, Yongdong
期刊：
Industrial and Engineering Chemistry Research ,2017年56(17):5021-5032 ISSN：0888-5885
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zhang, Hui; Zeng, Jiayun; Hu, Nan; Wang, Fang; Xue, Jinhua; Wang, Yongdong] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Sui, Yang] Hunan Taohuajiang Nucl Power Co Ltd, Yiyang 413000, Peoples R China.
通讯机构：
[Ding, Dexin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
摘要：
A novel amidoxime-based adsorbent of titanium-molybdopyrophosphate-g-amidoxime (TMP-g-AO) was prepared by chemical coprecipitation and subsequent chemical modifications. The successful grafting of acrylonitrile group and the subsequent conversion of acrylonitrile group to amidoxime groups were characterized by scanning electron microscopy-energy dispersive spectroscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, N<inf>2</inf>-BET, and thermal analysis. The adsorption behavior of uranium(VI) on TMP-g-AO was investigated for low concentration uranium solution by batch experiments at a fixed pH of 8.2 ±0.1. It is found that the adsorption rate of uranium from solution was 99.77% when the uranium concentration was 42.3 μg/L, pH = 8.2 ±0.1, temperature = 298.15 K, and the adsorbent dosage = 0.05 g. The kinetic data follow the pseudo-second-order model, and adsorption equilibrium data fit the Langmuir model well. The thermodynamics parameters (ΔS, ΔH, and ΔG) indicate that the adsorption process is spontaneous and endothermic. The functional TMP-g-AO adsorbent exhibits good selectivity and affinity for uranium ions under coexisting multimetal ions except for Fe<sup>3+</sup>and Co<sup>2+</sup>. Desorption was performed, and the adsorption rate of uranium by TMP-g-AO only decreased 1.42% after five consecutive adsorption-desorption cycles. In order to evaluate the potential application of TMP-g-AO for uranium extraction from seawater, the experiments on adsorption of uranium(VI) from natural seawater and the uranium-doped seawater were conducted, and the adsorbent exhibited a high adsorption rate of uranium(VI). The results show that TMP-g-AO could be a very promising adsorbent for uranium extraction from seawater. ©2017 American Chemical Society.
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英文
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Production of zinc and lead concentrates from lean oxidized zinc ores by alkaline leaching followed by two-step precipitation using sulfides
作者：
Liu, Qing* ;Zhao, Youcai;Zhao, Guodong
期刊：
Hydrometallurgy ,2011年110(1-4):79-84 ISSN：0304-386X
通讯作者：
Liu, Qing
作者机构：
[Liu, Qing] Univ S China, Sch Urban Construct, Hengyang 421001, Peoples R China.;[Zhao, Youcai; Liu, Qing] Tongji Univ, State Key Lab Pollut Control & Resource Reuse, Shanghai 200092, Peoples R China.;[Zhao, Guodong] Univ S China, Sch Nucl Resources & Nucl Fuel Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Liu, Qing] Univ S China, Sch Urban Construct, Hengyang 421001, Peoples R China.
关键词：
Precipitation<&wdkj&>Sodium sulfide<&wdkj&>Concentrate<&wdkj&>Alkaline
摘要：
An integrated hydrometallurgical process for the production of zinc and lead concentrates from lean oxidized zinc ores by alkaline leaching, followed by two-step sulfide precipitation of lead and zinc sulfides, is developed. The lean zinc oxidized ore was firstly ground to a size below 0.2 mm, followed by alkaline leaching at 90 °C for 120 min in NaOH solution, in which both zinc and lead are effectively extracted. Lead concentrates were then highly selectively and quantitatively produced from the leach solution by adding sodium sulfide as precipitant. Zinc concentrates were obtained in the same way from the Pb-free solution. Optimum conditions of lead precipitation were found to be 1.8 Na<inf>2</inf>S•9H<inf>2</inf>O/Pb weight ratio, 90 °C, 60 min and those for zinc precipitation were 2.4 Na<inf>2</inf>S•9H<inf>2</inf>O/Zn weight ratio, 90 °C, 180 min. Finally, a scale-up experiment was carried out and found that the lead and zinc total extraction both reached above 80% calculated from the ores and the quality of lead and zinc concentrates can meet industrial requirements for roasting processes. Meanwhile, it was found that the loss of NaOH is negligible and the main consumption of chemicals was that of sodium sulfide. ©2011 Elsevier Inc. All rights reserved.
语种：
英文
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Geochronology and geochemistry of porphyritic intrusions in the Duolong porphyry and epithermal Cu-Au district, central Tibet: Implications for the genesis and exploration of porphyry copper deposits
作者：
Sun, Jia* ;Mao, Jingwen* ;Beaudoin, Georges;Duan, Xianzhe* ;Yao, Fojun;Ouyang, Hegen;Wu, Yue;Li, Yubin;Meng, Xuyang
期刊：
Ore Geology Reviews ,2017年80:1004-1019 ISSN：0169-1368
通讯作者：
Sun, Jia;Mao, Jingwen;Duan, Xianzhe
作者机构：
[Mao, Jingwen; Ouyang, Hegen; Sun, Jia; Yao, Fojun; Sun, J; Mao, JW] Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.;[Sun, Jia; Meng, Xuyang] China Univ Geosci, Sch Geosci & Resources, Beijing 100083, Peoples R China.;[Beaudoin, Georges] Univ Laval, Dept Geol & Genie Geol, Quebec City, PQ G1V 0A6, Canada.;[Duan, Xianzhe] Univ South China, Sch Nucl Resource Engn, Hengyang 421001, Peoples R China.;[Wu, Yue] Yangtze Univ, Sch Earth Environm & Water Resource, Wuhan 430100, Peoples R China.
通讯机构：
[Sun, J; Mao, JW] Chinese Acad Geol Sci, Inst Mineral Resources, MLR Key Lab Metallogeny & Mineral Assessment, Beijing 100037, Peoples R China.;[Duan, Xianzhe] Univ South China, Sch Nucl Resource Engn, Hengyang 421001, Peoples R China.
关键词：
Porphyry copper deposits<&wdkj&>Emplacement depth<&wdkj&>Amphibole<&wdkj&>Magnetite<&wdkj&>Mineral exploration
摘要：
The Duolong district in central Tibet hosts a number of porphyry as well as high sulfidation epithermal copper–gold deposits and prospects, associated with voluminous calc-alkaline volcanism and plutonism. In this study, we present new geochronological, geochemical, isotopic and mineralogical data for both economically mineralized and barren porphyritic intrusions from the Duobuza and Naruo porphyry Cu–Au deposits. Zircon U–Pb analyses suggest the emplacement of economically mineralized granodiorite porphyry and barren granodiorite porphyry at Naruo deposit took place at 119.8 ± 1.4 Ma and 117.2 ± 0.5 Ma, respectively. Four molybdenite samples from the Naruo deposit yield an isochron Re–Os age of 119.5 ± 3.2 Ma, indicating mineralization occurred synchronously with the emplacement of the early granodiorite porphyry. At Duobuza deposit, the barren quartz diorite porphyry intruded at 119.5 ± 0.7 Ma, and two economically mineralized intrusions intruded at 118.5 ± 1.2 Ma (granodiorite porphyry) and 117.5 ± 1.2 Ma (quartz diorite porphyry), respectively. Petrographic investigations and geochemical data indicate that all of the porphyritic intrusions were oxidized, water rich, and subduction-related calc-alkaline magmas. Zircons from the porphyritic intrusions have a wide range in the Ε<inf>Hf</inf>(0–11.1) indicating that they were sourced from mixing of mantle-derived mafic, and crust-derived felsic melts. Moreover, the variation of trace element content of plagioclase phenocrysts indicates that the magma chambers were recharged by mafic magmas. Comparison of the composition of amphibole phenocrysts indicates the porphyry copper–gold mineralization at Duolong was generated in magma chambers at low crystallization temperatures and pressures (754°to 791 °C, 59 M to 73 MPa, n = 8), and under highly oxidizing conditions (ΔNNO 2.2 to 2.7, n = 8). In contrast, barren intrusions were sourced from the magma chambers with higher crystallization temperatures and pressures (816°to 892 °C, 111 to 232 MPa, n = 22) that were less oxidizing (ΔNNO 0.6 to 1.6, n = 22). The requirement for a thermal contrast is supported by the declining of Ti content in magnetite crystals in barren intrusions (12,550 to 34,200 ppm) versus those from economically mineralized intrusions (600 to 3400 ppm). Moreover, the V content in magnetite crystals from economically mineralized intrusions (990 to 2510 ppm) is lower than those recorded from barren intrusions (2610 to 3510 ppm), which might reflect the variation in oxidation state of the magma. The calculated water solubility of the magma forming the economically mineralized intrusions (3.2–3.7 wt%) is lower than that of magma forming the barren intrusions (4.6–6.4 wt%). Based on the chemical–physical characteristics of economically mineralized magma, our study suggests that the development of porphyry Cu–Au mineralization at Duolong was initiated by shallow-level emplacement of a magma that crystallized at lower temperatures and pressures. Experimental studies show that copper and water solubilities in silicate melts decrease with falling temperatures and pressures, indicating metals and ore-forming fluids are more likely to be released from a magma reservoir emplaced at shallow crustal levels. We propose the magnetite might be a convenient exploration tool in the search for porphyry copper mineralization because the variations in Ti and V content of mineral concentrates and rock samples are indicative of barren versus mineralized intrusions. ©2016 Elsevier B.V.
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英文
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Removal and recovery of uranium (VI) from aqueous solutions by immobilized Aspergillus niger powder beads
作者：
Ding, De-Xin* ;Tan, Xiang;Hu, Nan;Li, Guang-Yue;Wang, Yong-Dong;Tan, Yan
期刊：
Bioprocess and Biosystems Engineering ,2012年35(9):1567-1576 ISSN：1615-7591
通讯作者：
Ding, De-Xin
作者机构：
[Li, Guang-Yue; Tan, Yan; Hu, Nan; Tan, Xiang; Ding, De-Xin; Wang, Yong-Dong] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Tan, Yan; Ding, De-Xin] Cent S Univ, Sch Resources & Safety Engn, Changsha 410083, Peoples R China.;[Ding, De-Xin] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, 28 W Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, De-Xin] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, 28 W Changsheng Rd, Hengyang 421001, Hunan, Peoples R China.
关键词：
Biosorption<&wdkj&>Uranium<&wdkj&>Aspergillus niger<&wdkj&>Equilibrium<&wdkj&>Kinetics
摘要：
The immobilized Aspergillus niger powder beads were obtained by entrapping nonviable A. niger powder into Ca-alginate gel. The effects of pH, contact time, initial uranium (VI) concentration and biomass dosage on the biosorption of uranium (VI) onto the beads from aqueous solutions were investigated in a batch system. Biosorption equilibrium data were agreeable with Langmuir isotherm model and the maximum biosorption capacity of the beads for uranium (VI) was estimated to be 649.4 mg/g at 30 °C. The biosorption kinetics followed the pseudo-second-order model and intraparticle diffusion equation. The variations in enthalpy (26.45 kJ/mol), entropy (0.167 kJ/mol K) and Gibbs free energy were calculated from the experimental data. SEM and EDS analysis indicated that the beads have strong adsorption capability for uranium (VI). The adsorbed uranium (VI) on the beads could be released with HNO3 or HCl. The results showed that the immobilized A. niger powder beads had great potential for removing and recovering uranium (VI) from aqueous solutions. ©Springer-Verlag 2012.
语种：
英文
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Metal Pollution in Huayuan River in Hunan Province in China by Manganese Sulphate Waste Residue
作者：
Hu, Nan;Zheng, Ji-Fang* ;Ding, De-Xin;Liu, Jun;Yang, Lu-Qing;Yin, Jie;Li, Guang-Yue;Wang, Yong-Dong;Liu, Yu-Long
期刊：
Bulletin of Environmental Contamination and Toxicology ,2009年83(4):583-590 ISSN：0007-4861
通讯作者：
Zheng, Ji-Fang
作者机构：
[Li, Guang-Yue; Liu, Yu-Long; Yin, Jie; Zheng, Ji-Fang; Yang, Lu-Qing; Hu, Nan; Ding, De-Xin; Liu, Jun; Wang, Yong-Dong] Univ S China, Key Discipline Lab Natl Def Biol Technol Uranium, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Zheng, Ji-Fang] Univ S China, Key Discipline Lab Natl Def Biol Technol Uranium, Hengyang 421001, Hunan, Peoples R China.
关键词：
Huayuan River;Water pollution;Sediment;Manganese sulphate waste residue;Speciation
摘要：
The Huayuan River in Hunan Province in China is subject to ongoing mining activity with Mn extraction. In this study, the level and environmental significance of metals (including Mn, Cd, Pb, Cu, Zn, Ni and Fe) concentrations in the surface water and river sediments have been investigated along a 187 km reach of the Huayuan River. Using the X-ray fluorescence (XRF) analysis, we analyzed the characterization of metals in manganese sulphate waste residue (MSWR) deposited along the bank of Huayuan River. The speciation of metals in both sediment and MSWR was established using the BCR-three step sequential extraction procedure. In the water samples, the average concentrations of Mn, Cd and Pb exceeded the acceptable concentrations for drinking water in the WHO Guidelines for drinking water quality, Vol. 1, Recommendations, Geneva (2004) and Chinese (GB 5749-2006) guidelines, respectively. The average concentrations of Mn, Cd, Pb and Zn in the river sediments were found to be considerably higher than the corresponding world average shale values. The percentages of Cd (31.4%), Mn (31.1%), Zn (12.8%) and Pb (8.1%) associated with exchangeable and weak acid fraction in the sediments were higher than other metals. Mn (5.81%), Zn (0.208%), Pb (0.0292%) and Cd (0.0113%) were identified in MSWR by XRF analysis. The percentages of Mn, Cd, Zn and Pb associated with the exchangeable and weak acid soluble fraction in MSWR were 41.9%, 31.1%, 23.8% and 9.8%, respectively. The peak solute and sediment-bound metal concentrations were found at the sites of MSWR deposited along the bank of Huayuan River. The results suggested that MSWR deposited along the bank may have a closely relation with the metal pollution of Huayuan River. The results obtained may be useful to assess both short and long-term environmental impact of the MSWR deposited activities and support decisions for a future remediation of this river. ©2009 Springer Science+Business Media, LLC.
语种：
英文
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Studies on adsorption of uranium (VI) from aqueous solution by wheat straw
作者：
Wang, Xiao;Xia, Liangshu* ;Tan, Kaixuan;Zheng, Weina
期刊：
Environmental Progress and Sustainable Energy ,2012年31(4):566-576 ISSN：1944-7442
通讯作者：
Xia, Liangshu
作者机构：
[Zheng, Weina; Wang, Xiao] Univ S China, Sch Chem & Chem Engn, Hengyang 421001, Hunan, Peoples R China.;[Tan, Kaixuan; Xia, Liangshu] Univ S China, Sch Nucl Resources & Nucl Fuel Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Xia, Liangshu] Univ S China, Sch Nucl Resources & Nucl Fuel Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
wheat straw<&wdkj&>uranium<&wdkj&>modified<&wdkj&>adsorption<&wdkj&>mechanism
摘要：
A fundamental investigation on the removal of uranium from aqueous solutions by wheat straw was conducted in batch conditions. The influence of different experimental parameters such as modified methods, pH, contact time, adsorbent dose, initial concentration, and temperature, on the kinetics of uranium removal was studied. The results showed that the higher adsorption rate of uranium on wheat straw was modified by NaOH. At 303 K and pH was 3.0, the saturation adsorption was up to 1.20 mg/g at approximately 120 min. The uranium uptake was quantitatively evaluated using sorption isotherms and the correlation coefficients showed that the Freundlich model gave a better fit than the Langmuir equation. The process followed a pseudo-second-order kinetics. Scanning electron microscope coupled with Fourier transform infrared analysis for wheat straw, demonstrated that uranium-containing sites existed on the surface structure with hydroxyl, carbonyl, Pi-O and Si=O groups. Copyright ©2011 American Institute of Chemical Engineers (AIChE).
语种：
英文
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Removal of SO_4~(2-), uranium and other heavy metal ions from simulated solution by sulfate reducing bacteria
作者：
Wang Qing-liang* ;Ding De-xin;Hu E-ming;Yu Run-lan;Qiu Guan-zhou
期刊：
Transactions of Nonferrous Metals Society of China ,2008年18(6):1529-1532 ISSN：1003-6326
通讯作者：
Wang Qing-liang
作者机构：
[Wang Qing-liang; Yu Run-lan; Qiu Guan-zhou] Cent S Univ, Sch Minerals Proc & Bioengn, Changsha 410083, Peoples R China.;[Ding De-xin; Wang Qing-liang; Hu E-ming] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
通讯机构：
[Wang Qing-liang] Cent S Univ, Sch Minerals Proc & Bioengn, Changsha 410083, Peoples R China.
会议名称：
24th International Mineral Processing Congress (IMPC)
会议时间：
SEP 24-28, 2008
会议地点：
Beijing, PEOPLES R CHINA
会议主办单位：
[Wang Qing-liang;Yu Run-lan;Qiu Guan-zhou] Cent S Univ, Sch Minerals Proc & Bioengn, Changsha 410083, Peoples R China.^[Wang Qing-liang;Ding De-xin;Hu E-ming] Univ S China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词：
sulfate reducing bacteria;in-situ leaching of uranium;radioactively contaminated groundwater;bioremediation
摘要：
In the case of in-situ leaching of uranium, the primitive geochemical environment for groundwater is changed since leachant is injected into the water bearing uranium deposit. This increases the concentration of SO_4~(2-), uranium and other heavy metal ions and results in the groundwater contamination. The effects of pH values of the simulated solution on the reduction of SO_4~(2-) and the removal of uranium and other heavy metal ions by sulfate reducing bacteria(SRB) were studied. The results show that, when the pH value of the simulated solution is about 8, the reduction rate of SO_4~(2-) by SRB and the removal rate of uranium, Mn~(2+), Zn~(2+), Pb~(2+) and Fe~(2+) will reach their highest values. A bioremediation technique for remediation of groundwater in in-situ leaching uranium mine can be developed.
语种：
英文
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Vegetation composition and Ra-226 uptake by native plant species at a uranium mill tailings impoundment in South China
作者：
Hu, Nan;Ding, Dexin* ;Li, Guangyue;Zheng, Jifang;Li, Le;Zhao, Weichao;Wang, Yongdong
期刊：
Journal of Environmental Radioactivity ,2014年129:100-106 ISSN：0265-931X
通讯作者：
Ding, Dexin
作者机构：
[Ding, Dexin; Zheng, Jifang; Li, Le; Li, Guangyue; Hu, Nan; Wang, Yongdong; Zhao, Weichao] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, Dexin] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.
关键词：
Uranium<&wdkj&>Radium<&wdkj&>Mill tailings impoundment<&wdkj&>Vegetation composition<&wdkj&>Hyperaccumulator<&wdkj&>Phytoremediation
摘要：
A field investigation was conducted for the vegetation composition and <sup>226</sup>Ra uptake by native plant species at a uranium mill tailings impoundment in South China. 80 species belonging to 67 genera in 32 families were recorded in the sampling sites. The Poaceae and Asteraceae were the dominant families colonizing the impoundment. The number of the plant species and vegetation community composition in the sampling sites seemed most closely related to the activities of <sup>226</sup>Ra and the pH value of the uranium tailings. The plant species in the sampling sites with relatively low activities of <sup>226</sup>Ra and relatively high pH value formed a relatively stable vegetation community. The plant species in the sampling sites with medium activities of <sup>226</sup>Ra and medium pH value formed the transitional vegetation community. The plant species in the sampling sites with relatively high activities of <sup>226</sup>Ra and relatively low pH value formed a simple unstable vegetation community that was similar to that on the unused grassland. The activities of <sup>226</sup>Ra and transfer factors (TFs) varied greatly with the plant species. The high activities of <sup>226</sup>Ra and TFs were found in the leaves of Pteris multifida (150.6Bq/g of AW;9.131), Pteridium aquilinum (122.2Bq/g of AW;7.409), and Dryopteris scottii (105.7Bq/g of AW;6.408). They satisfied the criteria for a hyperaccumulator for <sup>226</sup>Ra. They may be the candidates for phytoremediation of <sup>226</sup>Ra in the uranium mill tailings impoundment areas and the contaminated soils around. ©2014 Elsevier Ltd.
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英文
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Effects of acid/alkaline pretreatment and gamma-ray irradiation on extracellular polymeric substances from sewage sludge
作者：
Xie Shuibo* ;Wu Yuqi;Wang Wentao;Wang Jingsong;Luo Zhiping;Li Shiyou
期刊：
Radiation Physics and Chemistry ,2014年97:349-353 ISSN：0969-806X
通讯作者：
Xie Shuibo
作者机构：
[Wang Wentao; Xie Shuibo; Wu Yuqi; Wang Jingsong; Luo Zhiping; Li Shiyou] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Tec, Hengyang 421001, Peoples R China.;[Xie Shuibo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
通讯机构：
[Xie Shuibo] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Tec, Hengyang 421001, Peoples R China.
关键词：
Extracellular polymeric substances (EPS)<&wdkj&>Gamma-ray irradiation<&wdkj&>Acid/alkaline pretreatment<&wdkj&>Sludge disintegration
摘要：
In order to investigate the mechanism of extracellular polymeric substances (EPS) influencing sludge characteristics, variations of extractable EPS from municipal sewage sludge by acid/alkaline pretreatment and gamma-ray irradiation were studied. The changes in constituents of EPS were analyzed by UV-vis spectra and SEM images. The effects of alkaline pretreatment and gamma-ray irradiation on the functional groups in EPS were investigated by Fourier transform infrared (FTIR) spectrometer. Results showed that the extractable EPS increased clearly with increasing irradiation dose from 0 to 15 kGy. UV-vis spectra indicated that a new absorption band from 240 nm to 300 nm existed in all irradiated samples, apart from acid condition. The results of FTIR spectroscopic analysis indicated that, irradiation influenced major functional groups in EPS, such as protein and polysaccharide, and these effects were clearer under alkaline condition. SEM images provided that after alkaline hydrolysis, gamma-ray irradiation was more effective in resulting in the sludge flocs and cells broken, compared with acid pretreatment (pH 2.50). (c) 2013 Published by Elsevier Ltd.
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英文
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