摘要：
Uranium mining operations produce large volumes of acidic uranium mining wastewater, necessitating the development of environmentally friendly and recyclable materials for efficient uranium removal and recovery. The current study successfully produced hydroxyapatite (HAP-L) and magnetic phosphate composites (CaFeP-1, CaFeP-2, and FePO4) through a combination of mixing, ultrasonication, hydrothermal precipitation, and calcination methods. The research explores the influence of various parameters such as pH, solid-liquid ratio, contact time, initial uranium concentration, co-existing ions, and recyclability on the uranium removal efficiency of these materials. The findings indicate exceptional uranium adsorption capacities, with CaFeP-1 exhibiting the highest capacity among the materials, especially in acidic environments. Moreover, CaFeP-1 displays strong resistance to interference from other ions and can be recycled multiple times while maintaining high removal rates. Treatment of acidic uranium mining wastewater by CaFeP-1 results in pH adjustment and the reduction of uranium and other ion concentrations, making it a promising solution for comprehensive remediation of acidic uranium mining wastewater. The U(VI) removal mechanism by CaFeP-1 was validated through XRD, FT-IR, and XPS results. The U(VI) removal was attributed to processes such as dissolution-precipitation, surface complexation, and ion exchange. The formation of sodium uranyl phosphate hydrate was identified as a new product following U(VI) abatement by CaFeP-1. In summary, CaFeP-1 shows great potential for the effective treatment of acidic uranium mining wastewater.
期刊：
Journal of Cleaner Production,2024年446:141306 ISSN：0959-6526
通讯作者：
Xilong Xue
作者机构：
Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, Hunan, China;[Pengcheng Sun; Jiale Li; Yan He] School of Resources, Environment and Safety Engineering, University of South China, Hengyang, 421001, Hunan, China;National Key Laboratory of Ni&Co Associated Minerals Resources Development and Comprehensive Utilization, Jinchuan Group Co., Ltd., Jinchang, 737100, Gansu, China;[Xiao Zhang; Dexin Ding] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, Hunan, China<&wdkj&>School of Resources, Environment and Safety Engineering, University of South China, Hengyang, 421001, Hunan, China;[Xilong Xue] School of Resources, Environment and Safety Engineering, University of South China, Hengyang, 421001, Hunan, China<&wdkj&>National Key Laboratory of Ni&Co Associated Minerals Resources Development and Comprehensive Utilization, Jinchuan Group Co., Ltd., Jinchang, 737100, Gansu, China
通讯机构：
[Xilong Xue] S;School of Resources, Environment and Safety Engineering, University of South China, Hengyang, 421001, Hunan, China<&wdkj&>National Key Laboratory of Ni&Co Associated Minerals Resources Development and Comprehensive Utilization, Jinchuan Group Co., Ltd., Jinchang, 737100, Gansu, China
摘要：
Heap leaching uranium tailings (HLUTs) contain radionuclides and sulfuric acid, presenting some challenges for the disposal of cemented HLUTs backfill (CUTB), including low stability and potential environmental contamination. In light of these issues, using a blend of cement clinker (CL) and high content phosphorus slag (PS) as binders to replace traditional cement for the preparation of green and cost-effective CUTB were proposed. The fluidity, setting time (ST), mechanical properties, Radon (Rn) exhalation rate, uranium (U) occurrence form, U (Ⅵ) leaching behavior, and microstructure of CUTB with different PS contents were investigated. The results showed that the fluidity, bleeding rate and ST of slurry (PS content >40%) met the filling requirements. The strength of PS-based CUTB was initially low, but rapidly increased in subsequent periods, surpassing 2 MPa at 28 d and 4.5 MPa at 90 d (with 50–70% PS content). Moreover, the Rn exhalation rates and U (Ⅵ) leaching levels of CUTB were far lower than the stipulated limits. When PS content exceeded 50%, the migratory uranium content in CUTB was below 10% with low migration risks. With the addition of PS, the amount and degree of polymerization of C–S–H gels in the matrix increased, while gypsum and CH content decreased. The S/S of U (Ⅵ) and SO42− was attributed to the combined effects of chemical immobilization of nascent minerals and physical adsorption/encapsulation of hydration products. Additionally, these hydrates effectively sealed micro-cracks on HLUTs particles surfaces and filled interlocking pores to decrease Rn exhalation. PS-based CUTB exhibited a high capacity increasing ratio and low cost. This research can promote the utilization of hazardous solid wastes such as HLUTs, reduce carbon dioxide emissions, and provide a theoretical basis for ensuring green and safe production in mining.
摘要：
Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the environment. Among these measurement methods, the closed-loop method is frequently used. However, traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas-solid interface in the accumulation chamber. The CFD-based technique was applied to predict the radon concentration distribution in a limited space, allowing radon accumulation and exhalation inside the chamber intuitively and visually. In this study, three radon exhalation rates were defined, and two structural ventilation tubes were designed for the chamber. The consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was verified. The effects of the vent tube structure and flow rate on the radon uniformity in the chamber; permeability, insertion depth, and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were investigated. Based on the results, increasing the insertion depth from 1 to 5 cm decreased the effective decay constant by 19.55%, whereas the curve-fitted radon exhalation rate decreased (lower than the initial value) as the deviation from the initial value increased by approximately 7%. Increasing the effective diffusion coefficient from 2.77 x 10-7 to 7.77 x 10-6 m2 s-1 made the deviation expand from 2.14 to 15.96%. The conclusion is that an increased insertion depth helps reduce leakage in the chamber, subject to notable back-diffusion, and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion effect. The CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and, thus, the accurate measurement of the radon exhalation rate.
关键词：
Efflux pumps;Heavy metal resistance;Secretome
摘要：
Heavy metal-resistant bacteria secrete extracellular proteins (e-PNs). However, the role of e-PNs in heavy metal resistance remains elusive. Here Fourier Transform Infrared Spectroscopy implied that N-H, C=O and NH(2)-R played a crucial role in the adsorption and resistance of Ni(2+) in the model organism Cuprividus pauculus 1490 (C. pauculus). Proteinase K treatment reduced Ni(2+) resistance of C. pauculus underlining the essential role of e-PNs. Further three-dimension excitation-emission matrix fluorescence spectroscopy analysis demonstrated that tryptophan proteins as part of the e-PNs increased significantly with Ni(2+) treatment. Proteomic and quantitative real-time polymerase chain reaction data indicated that major changes were induced in the metabolism of C. pauculus in response to Ni(2+). Among those lipopolysaccharide biosynthesis, general secretion pathways, Ni(2+)-affiliated transporters and multidrug efflux play an essential role in Ni(2+) resistance. Altogether the results provide a conceptual model for comprehending how e-PNs contribute to bacterial resistance and adsorption of Ni(2+).
摘要：
Uranium, regarded as an important element in nuclear fission energy schemes, is harmful to public health owing to its high toxicity and radioactivity. Herein, a novel fluorescent probe (SC4A@Tb3+) was developed using a one-step liquid-phase method with 4-sulfocalix[4]arene (SC4A) and rare earth-metal ions (Tb3+) as precursors to realize the accurate monitoring of uranyl ion (UO22+) detection. Based on the dynamic quenching mechanism, the SC4A@Tb3+ fluorescence quenching sensor for UO22+ detection was in the linear range of 0-0.36 mu M, with a detection limit of 20 mu g center dot L-1, and successfully quantified UO22+ in water and human serum samples. These results suggest that SC4A@Tb3+ is a potential sensing material for UO22+ detection.
摘要：
To investigate the strengthening effects and mechanisms of bioaugmentation on the microbial remediation of uranium-contaminated groundwater via bioreduction coupled to biomineralization, two exogenous microbial consortia with reducing and phosphate-solubilizing functions were screened and added to uranium-contaminated groundwater as the experimental groups (group B, reducing consortium added; group C, phosphate-solubilizing consortium added). β-glycerophosphate (GP) was selected to stimulate the microbial community as the sole electron donor and phosphorus source. The results showed that bioaugmentation accelerated the consumption of GP and the proliferation of key functional microbes in groups B and C. In group B, Dysgonomonas, Clostridium_sensu_stricto_11 and Clostridium_sensu_stricto_13 were the main reducing bacteria, and Paenibacillus was the main phosphate-solubilizing bacteria. In group C, the microorganisms that solubilized phosphate were mainly unclassified_f_Enterobacteriaceae. Additionally, bioaugmentation promoted the formation of unattached precipitates and alleviated the inhibitory effect of cell surface precipitation on microbial metabolism. As a result, the formation rate of U-phosphate precipitates and the removal rates of aqueous U(VI) in both groups B and C were elevated significantly after bioaugmentation. The U(VI) removal rate was poor in the control group (group A, with only an indigenous consortium). Propionispora, Sporomusa and Clostridium_sensu_stricto_11 may have played an important role in the removal of uranium in group A. Furthermore, the addition of a reducing consortium promoted the reduction of U(VI) to U(IV), and immobilized uranium existed in the form of U(IV)-phosphate and U(VI)-phosphate precipitates in group B. In contrast, U was present mainly as U(VI)-phosphate precipitates in groups A and C. Overall, bioaugmentation with an exogenous consortium resulted in the rapid removal of uranium from groundwater and the formation of U-phosphate minerals and served as an effective strategy for improving the treatment of uranium-contaminated groundwater in situ.
摘要：
An in vivo model is necessary for toxicology. This review analyzed the uses of zebrafish (Danio rerio) in toxicology based on bibliometrics. Totally 56,816 publications about zebrafish from 2002 to 2023 were found in Web of Science Core Collection, with Toxicology as the top 6 among all disciplines. Accordingly, the bibliometric map reveals that "toxicity" has become a hot keyword. It further reveals that the most common exposure types include acute, chronic, and combined exposure. The toxicological effects include behavioral, intestinal, cardiovascular, hepatic, endocrine toxicity, neurotoxicity, immunotoxicity, genotoxicity, and reproductive and transgenerational toxicity. The mechanisms include oxidative stress, inflammation, autophagy, and dysbiosis of gut microbiota. The toxicants commonly evaluated by using zebrafish model include nanomaterials, arsenic, metals, bisphenol, and dioxin. Overall, zebrafish provide a unique and well-accepted model to investigate the toxicological effects and mechanisms. We also discussed the possible ways to address some of the limitations of zebrafish model, such as the combination of human organoids to avoid species differences.
作者：
Ye, Yongjun;Chen, Mengge;Chen, Guangling;Xia, Ming;Yu, Ting;...
期刊：
Journal of Environmental Radioactivity,2024年272:107353 ISSN：0265-931X
通讯作者：
Ye, YJ
作者机构：
[Ye, Yongjun; Xia, Ming; Wang, Haofeng; Chen, Mengge; Chen, Guangling; Yu, Ting] Univ South China, Natl Joint Engn Res Ctr Airborne Pollutants Contro, Hengyang 421001, Hunan, Peoples R China.;[Ye, Yongjun] Univ South China, Lab Natl Def Biotechnol Uranium Min & Hydromet, Hengyang 421001, Hunan, Peoples R China.;[Ye, Yongjun] Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ye, YJ ] U;Univ South China, Sch Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
摘要：
There is a significant impact of the radon diffusion coefficient and the free radon production rate on the exhalation of radon from porous materials that can be regarded as spheres, hexahedrons, or cylinders. To understand this effect, the radon exhalation rules of spherical porous media with different radii were studied according to the radon diffusion migration theory. A specialized method for simultaneous determination of the radon diffusion coefficient and the free radon production rate of the spherical porous media was proposed, and applied to determine the above two parameters for two hemispherical test blocks with different radii. The results show that:(1) For spherical porous media with a certain radon diffusion length (L(d)), as the radius (r(0)) of the sphere increases, the radon exhalation rate first increases, and tends to stabilize at r(0)≥6L(d); The free radon release share gradually decreases from approximately 1, and drops to a steady state at r(0)≥18L(d). (2) Compared with conventional methods, the relative error of the free radon production rate determined by the proposed method is within 3.9%, which verifies the reliability of the new method.
期刊：
Separation and Purification Technology,2024年338:126537 ISSN：1383-5866
通讯作者：
Zhongran Dai<&wdkj&>Yuan Gao<&wdkj&>Le Li
作者机构：
[Zhongran Dai; Lijie Chen; Beichao Liang] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China;[Yuan Gao] School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China;[Weilin Zhang] College of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, Hunan, China;[Le Li] Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>College of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, Hunan, China
通讯机构：
[Zhongran Dai; Le Li] K;[Yuan Gao] S;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>College of Public Health, Hengyang Medical School, University of South China, Hengyang 421001, Hunan, China<&wdkj&>School of Chemical Engineering and Technology, China University of Mining & Technology, Xuzhou, Jiangsu 221116, China
摘要：
Utilizing elemental doping and defect engineering are effective means to enhance the efficiency of g-C3N4 materials for photocatalytic removal of uranium. In this investigation, we synthesized a defective g-C3N4 photocatalyst co-decorated with K+ doping and cyano groups (KHCN) through a straightforward one-step alkali etching process. The alkali etching not only enhances the specific surface area to improve the adsorption of uranium by KHCN but also significantly accelerates the photocatalytic removal of uranium through the introduction of K+ and cyano groups. The KHCN can almost completely remove 40 mg/L of U(VI) under air and visible LED light irradiation (pH 5.0, 298.15 K). Notably, the photocatalytic removal of U(VI) by KHCN demonstrated excellent selectivity and reusability. The mechanism studies reveal that alkali etching-induced introduction of K+ ions and cyano groups enhances visible light absorption, strengthens the efficiency of photogenerated carrier separation, and reduces the band gap. The activation of U(VI) in solution primarily occurs through photogenerated e- and O2–, subsequently immobilizing as metastudtite ((UO2)O2·2H2O). This study provides a viable approach for synthesizing highly efficient photocatalytic materials for uranium removal, leveraging synergistic doping and defect engineering.
通讯机构：
[Wang, YD ] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Min, Heng Yang 421001, Hunan, Peoples R China.
关键词：
Electron transfer mechanism;U(VI) bioreduction;Cytochrome c;Oxidative phosphorylation;Bacillus sp. X02
摘要：
With the development of the uranium mining industry, the remediation of uranium pollution is an urgent environmental problem to be solved. Bioreduction is currently recognized as a U(VI) bioremediation method with good application prospects. However, inadequate reporting of uranium-reducing bacteria and low bioreduction efficiency are the main reasons limiting the application of the bioreduction method. In this paper, we isolated an efficient uranium-reducing bacterium, Bacillus sp. X02, explored the effect of U(VI) on bioreduction efficiency through electron transport mechanisms. The results showed that the maximum removal and reduction rate were 98.35 % and 62.43 %, respectively. Further studies revealed that the efficiency of extracellular electron transport of Bacillus sp. X02 was enhanced under U(VI) exposure. But uranium stress down-regulated the expression of F-type ATPase, Cytochrome c reductase ISP, Cytochrome c oxidase, and Cytochrome bd complex, inhibited the processes of complex III, complex IV, and ATP synthesis in the oxidative phosphorylation electron transport pathway, decreasing the electron transfer and U(VI) reduction capacity of Bacillus sp. X02 ultimately. This work proposed a new electron transfer pathway for U(VI) bioreduction and provided new insights into the effect of uranium on bioreduction efficiency.
期刊：
Separation and Purification Technology,2023年307:122873 ISSN：1383-5866
通讯作者：
Zhongran Dai
作者机构：
[Ding, Dexin; Li, Le; Dai, Zhongran; Chen, Lijie; Lian, Junjie] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Min, Hengyang 421001, Peoples R China.;[Gao, Yuan] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Jiangsu, Peoples R China.
通讯机构：
[Zhongran Dai] K;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China
摘要：
Photocatalytic reduction of soluble hexavalent uranium to insoluble tetravalent uranium is a promising strategy for uranium-containing wastewater treatment, while this method generally requires anaerobic conditions and/or the addition of sacrificial agents. Obviously, providing anaerobic environment and sacrificial agent will not only increase the cost but also causes secondary pollution. Thus, efficient removal of U(VI) by photocatalytic tech-niques under air atmosphere without sacrificial agents is an urgent task and great challenge. In this work, a novel O, K co-doped g-C3N4 (OKDCN) photocatalyst was synthesized by a simple thermal reaction for the photore-duction removal of U(VI) under air atmosphere without sacrificial agents. Batch experiments show that the OKDCN-2 can nearly completely remove U(VI) in the solution within 120 min at pH 5.0. In addition, the OKDCN showed excellent reusability and selectivity in the process of photocatalytic reduction of U(VI). Further mech-anism studies show the doping of O and K can improve the photogenerated carrier transfer and separation ef-ficiency of OKDCN, and then improve the performance of photocatalytic reduction of uranium. These results provide a reference for breaking through some bottleneck issues in the research field of photocatalytic removal of U(VI).
通讯机构：
[Xixian Huang] S;[Dexin Ding] K;School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang 421001, China<&wdkj&>School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan 421001, China
摘要：
Amorphous ferrihydrite (Fh) is abundant in aquatic environments and sediments, and often coprecipitates with dissolved organic matter (DOM) to form mineral-organic aggregates. The Fe(II)-catalyzed transformation of Fh to crystalline Fe (oxyhydr)oxides (e.g., goethite) can result in the changes of uranium (U) species, but the effects of DOM molecules on the sequestration and stability of U during Fe (oxyhydr)oxides transformation are poorly understood. In this study, the associations of DOM molecules with U during the coprecipitation of DOM with Fh were evaluated, and the effects of DOM molecules on the kinetics of U release during Fe (oxyhydr)oxides transformation were investigated using a combination of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), X-ray photoelectron spectroscopy (XPS), and kinetic experiments. FT-ICR-MS results indicated that, in addition to phenolic and polyphenolic compounds with higher O/C ratios, portions of phenolic compounds with lower O/C ratios and aliphatic compounds were also contributed to UO(2)(2+) binding when Fh coprecipitated with DOM. In comparison, phenolic and polyphenolic compounds with higher O/C ratios and condensed aromatics were preferentially retained on Fe (oxyhydr)oxides during the transformation. XPS results further suggested that the coprecipitated DOM molecules facilitated the reduction of U(VI) to U(IV) during the transformation, possibly through providing electrons or acting as electron shuttles. The kinetic experiment results indicated that the transformation processes accelerated U release from Fe (oxyhydr)oxides, but the coprecipitated DOM molecules slowed down U release. Our results contribute to understanding the behaviors of U and predicting the sequestration of U in the environment.
作者：
Zhou, T. H.;He, L.;Deng, Q. W.;Ding, D. X.;Wang, Y. D.;...
期刊：
International Journal of Environmental Science and Technology,2023年20(2):1769-1778 ISSN：1735-1472
通讯作者：
Deng, QW
作者机构：
[Zhou, T. H.; He, L.; Chen, Y. X.; Wang, Y. D.; Ding, D. X.; Deng, QW; Deng, Q. W.] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Zhou, T. H.; He, L.; Chen, Y. X.; Deng, QW; Deng, Q. W.] Univ South China, Hengyang Key Lab Soil Pollut Control & Remediat, Hengyang 421001, Hunan, Peoples R China.;[Zhou, T. H.; He, L.; Chen, Y. X.; Wang, Y. D.; Ding, D. X.; Deng, QW; Deng, Q. W.] Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.;[He, L.] China Bluestar Chonfar Engn & Technol Co Ltd, Changsha 410007, Hunan, Peoples R China.
通讯机构：
[Deng, QW ] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;Univ South China, Hengyang Key Lab Soil Pollut Control & Remediat, Hengyang 421001, Hunan, Peoples R China.;Univ South China, Sch Resources Environm & Safety Engn, Hengyang 421001, Hunan, Peoples R China.
关键词：
Uranium and wastewater;Syngonium podophyllum;Endophytes;Integrated remediation
摘要：
Treatment of uranium-containing wastewater using a plant-microbe symbiotic system appears promising. To find a viable method for wastewater treatment containing low concentrations of uranium (5 mg/L or lower), a Syngonium(S) podophyllum-endophyte symbiotic system was designed and hydroponic remediation experiments were conducted. After 25 days of treatment, the uranium concentrations of the wastewater samples with uranium concentrations between 0.5 and 2.0 mg/L were lowered to below 0.05 mg/L. Analysis of the concentration data and transfer factors (TF) of uranium in plant roots, stems and leaves showed that S. podophyllum concentrated uranium mainly through its roots. Furthermore, Fourier transform infrared spectroscopy (FTIR) showed that the roots of S. podophyllum colonized by Bacteria XNN8 (separated from Typha orientalis, beef extract peptone medium, bacteria numbered eight) produced more sugars and -OH than that by the uncolonized S. podophyllum, hence promoting the binding effect of -OH on uranium in plants. Colonization by actinomycetes XNG3 (separated from Typha orientalis, modified Gao's No. 1 medium, actinomycetes numbered three) might either increase the content of C = O, COO-, C-O and C-N in the roots of S. podophyllum or strengthen the binding effect of these functional groups with uranium.
摘要：
Pollution from uranium tailings ponds poses a severe threat to aquatic ecosystems. However, its effects on litterfall decomposition in aquatic environments are uncertain. This study was conducted to investigate the effects of different species (Macleaya cordata and Typha orientalis Presl), sources (inside and outside the tailings pond), sites (above and below ground), initial biomass (1, 2, and 4 g) and initial ambient uranium concentrations (0, 1, and 3 mg/L) on the decomposition of uranium-containing litterfall. The study found that the above-mentioned indicators (litterfall self-characteristics and environmental factors) affect the decomposition of uranium-containing litterfall. The decomposition rate of litterfall in the water environment is related to the plant species, sites, and initial biomass, mainly due to the differences in the content of plant structural materials (cellulose, hemicellulose, and lignin). Uranium concentration is also an important factor affecting the decomposition of litterfall. A high concentration of uranium may affect the activities of microorganisms and thus inhibit the decomposition of litterfall, while a low concentration of uranium has the effect of accelerating the decomposition. In addition, the uranium content in M. cordata increased significantly after decomposition, but T. orientalis was the opposite, and both metal pools decreased significantly. At the same time, the underground parts of the two plants released more uranium than the aboveground parts. In conclusion, this study provides new insights and a scientific basis for the risks posed by the uranium mining industry.
作者机构：
[Huang, Tao; Zhou, Lulu; Yang, Chun-Hai] Changshu Inst Technol, Sch Mat Engn, Changshu 215500, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu 215500, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Jiangsu, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构：
[Tao Huang] S;School of Materials Engineering, Changshu Institute of Technology, 215500, China<&wdkj&>Suzhou Key Laboratory of Functional Ceramic Materials, Changshu Institute of Technology, Changshu, 215500, China<&wdkj&>School of Chemical Engineering & Technology, China University of Mining and Technology, Xuzhou, Jiangsu, 221116, China
作者机构：
[Li, Liuqin; Fang, Qi] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China;[Zhu, Nengwu] School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China;[Huang, Xixian] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>School of Environment and Energy, Guangdong Provincial Key Laboratory of Solid Wastes Pollution Control and Recycling, South China University of Technology, Guangzhou, Guangdong, 510006, PR China;[Ding, Yang] School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China
通讯机构：
[Yang Ding] S;School of Resource & Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, PR China<&wdkj&>Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, 421001, PR China
摘要：
The dynamic reactions of uranium (U) with iron (Fe) minerals change its behaviors in soil environment, however, how the coexisted constituents in soil affect U sequestration and release on Fe minerals during the transformation remains unclear. Herein, coupled effects of lead (Pb) and dissolved organic matter (DOM) on U speciation and release kinetics during the catalytic transformations of ferrihydrite (Fh) by Fe(II) were investigated. Our results revealed that the coexistence of Pb and DOM significantly reduced U release and increased the immobilization of U during Fh transformation, which were attributed to the enhanced inhibition of Fh transformation, the declined release of DOM and the increased U(VI) reduction. Specifically, the presence of Pb increased the coprecipitation of condensed aromatics, polyphenols and phenols, and these molecules were preferentially maintained by Fe (oxyhydr)oxides. The sequestrated polyphenols and phenols could further facilitate U(VI) reduction to U(IV). Additionally, a higher Pb content in coprecipitates caused a slower U release, especially when DOM was present. Compared with Pb, the concentrations of the released U were significantly lower during the transformation. Our results contribute to predicting U sequestration and remediating U-contaminated soils.
摘要：
According to the difficult problem of disposal and recovery of uranium-containing waste slag, the leaching experiment was conducted by using the secondary countercurrent leaching process. The results showed that under conditions particle size of 1 mm, reaction time of 120 min, leaching temperature of 90 & DEG;C, nitric acid concentration of 429 g/L, liquid-solid ratio of 2.2:1, hydrogen peroxide dosage of 30 mL/L in primary leaching, then the temperature was switched to 130 & DEG;C during the secondary leaching. The leaching rate of uranium in alkali slag was 99.73% and the content of the uranium in insoluble slag was 0.788%.
期刊：
Journal of Environmental Chemical Engineering,2023年11(5):110694 ISSN：2213-3437
通讯作者：
Huang, T;Li, HY
作者机构：
[Yao, Jiajie; Huang, Tao; Zhou, Lulu] Changshu Inst Technol, Sch Mat Engn, Suzhou 215500, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Suzhou 215500, Peoples R China.;[Zhang, Shu-wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.;[Li, Haiyan; Li, HY] Northeast Petr Univ, Coll Chem & Chem Engn, Daqing 163318, Peoples R China.
通讯机构：
[Huang, T ] C;[Li, HY ] N;Changshu Inst Technol, Sch Mat Engn, Suzhou 215500, Peoples R China.;Northeast Petr Univ, Coll Chem & Chem Engn, Daqing 163318, Peoples R China.
关键词：
Municipal solid waste incineration fly ash;Electrokinetics;Spatiotemporal electromigration of Cl;Continuous transferring;Electrolyzer
摘要：
The chloride (Cl) content in cement production and the other derivate products has been strictly restricted to avoid the corrosion of steels in building construction, which significantly narrows the possible utilization choices of Cl-abundant municipal solid waste incineration (MSWI) fly ashes. The reduction of soluble Cl from the source materials becomes an important prerequisite for efficient resource utilization of MSWI fly ashes. In this study, an electrochemical platform was constructed to investigate the potential pathways of the migration and transformation of Cl species in silicate-participated MSWI fly ashes during electrokinetic (EK) treatment. The factors including the operating time, voltage, and mass ratio of silicate to fly ashes were adjusted to evaluate the changes in pH, current, and Cl distribution. Each treated fly ash in the sampling area was evenly cut into 3 layers and 72 parts to accurately determine the distribution of Cl in the electrolyzer. More Cl- ions in the surface layer were electromigrated to the anode than those in the middle and bottom layers. The addition of silicate enhanced electromigration and improved the distribution uniformity of Cl species in the sampling area. The reduction in Ca2+ electromigration with the formation of C-S-H caused by the silicate guaranteed the continuous transfer and reactions of Cl- anions in the EK treatment.
期刊：
Journal of Environmental Radioactivity,2023年265:107223 ISSN：0265-931X
通讯作者：
Yongjun Ye
作者机构：
[Yu, Ting; Xia, Ming; Liu, Shuyuan; Chen, Daijia] School of Resources Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China;Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 421001, China;[Yan, Zhiguo] The Fourth Research and Design Engineering Corporation, China National Nuclear Corporation, Shijiazhuang, 050021, China;[Ye, Yongjun] School of Resources Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 421001, China
通讯机构：
[Yongjun Ye] S;School of Resources Environment and Safety Engineering, University of South China, Hengyang, Hunan, 421001, China<&wdkj&>Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, 421001, China
摘要：
Cavern is a place where workers often work in underground spaces, where radon is constantly released from surrounding rock surfaces. It is of great significance to develop effective ventilation to reduce radon in underground space for safe production and occupational health. For the purpose of controlling the radon concentration level in the cavern, the influence of upstream and downstream brattice length, upstream and downstream brattice to wall width on the volume average radon concentration and the plane average radon concentration at the height of the human respiratory zone (Z=1.6m) in the cavern, was studied by using the CFD (Computational fluid dynamics) method, and the operating parameters of ventilation induced by the brattice are optimized. The results show that the radon concentration in the cavern can be significantly reduced by using the brattice induced ventilation compared with no ventilation auxiliary facilities. This study provides a reference for local radon-reducing ventilation design of underground cavern.
