作者机构：
[Huang, Tao; Zhou, Lulu; Liu, Long-Fei] 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.;[Xie, Juan] Changshu Inst Technol, Sch Text Garment & Design, Changshu 215500, Peoples R China.;[Huang, Tao] China Univ Min & Technol, Sch Chem Engn & Technol, Xuzhou 221116, Peoples R China.;[Zhang, Shu-Wen] Univ South China, Nucl Resources Engn Coll, Hengyang 421001, Peoples R China.
通讯机构：
[Tao Huang; Juan Xie] S;School of Materials Engineering, Changshu Institute of Technology, Changshu 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 221116, China<&wdkj&>School of Textile, Garment, and Design, Changshu Institute of Technology, 215500, China
关键词：
Quadrivalent cerium;Laurylsulfonate green rust;Adsorption mechanism;Rare earth element;Synthesis optimization
摘要：
The layered laurylsulfonate intercalated green rust（lauryl-S GR） was synthesized to evaluate the influence of synthesis parameters and aqueous conditions on the adsorption of CeⅣ.The maximum adsorption capacity of 305.58 mg/g by lauryl-S GR was predictably obtained.The pseudo-first-order kinetic model was appropriate in fitting the whole uptake process in a weak acid environment.Three isotherm models including Langmuir, Freundlich, and Tempkin were all reliable in depicting the isotherm adsorption process.The maximum monolayer adsorption capacity of lauryl-S GR towards CeⅣ was 315.46 mg/g.Ce species including CeO and Ce2O3 besides CeO2 were matched in the XPS distribution, directly indicating the reduction reaction brought by FeⅡ in the GR occurred to hydrated CeⅣ ions during the adsorption.Nano-sized Ce particles attached to the lauryl-S GRs after the adsorption experiments were observed in the morphological characterization.Flocculated materials were formed on the surface of the lauryl-S GR at a pH of 7, which further reduced the active sites and disrupted the continuous uptake of CeⅣ to the lauryl-S GR.This study expands the application of GRs and supplies an ideal iron-based material for the construction of the affiliated recovery pathway to the traditional separation of Ce.
期刊：
Separation Science and Technology,2021年56(2):344-358 ISSN：0149-6395
通讯作者：
Huang, Tao
作者机构：
[Liu, Longfei; Huang, Tao] Changshu Inst Technol, Sch Chem & Mat Engn, 99,South 3rd Ring Rd, Changshu 215500, Jiangsu, Peoples R China.;[Huang, Tao] Changshu Inst Technol, Suzhou Key Lab Funct Ceram Mat, Changshu, Jiangsu, Peoples R China.;[Zhang, Shuwen] Univ South China, Nucl Resources Engn Coll, Hengyang, Peoples R China.
通讯机构：
[Huang, Tao] C;Changshu Inst Technol, Sch Chem & Mat Engn, 99,South 3rd Ring Rd, Changshu 215500, Jiangsu, Peoples R China.
关键词：
Arsenic;superparamagnetic iron oxide nanoparticle-coated pyrite;electrokinetic removal;three-dimensional electrode;enhancement
摘要：
Superparamagnetic iron oxide nanoparticle-coated pyrite microelectrodes were synthesized and applied for the arsenic removal from the binary system in a three-dimensional fluidized reactor. Arsenate adsorption was highly dependent on the environmental pH values. The maximum monolayer adsorption capacities were 12.83 mg/g and 9.28 mg/g for As(V) and As(III), respectively. The direct contact between nucleus and target contaminants evidently affected As(III) equilibrium adsorption. Voltage gradient had a more remarkable influence on the arsenic removal compared with the other parameters in the optimization. A continuous flow was recommended in the industrial application based on the regeneration and reuse of adsorbent.
通讯机构：
[Shuibo Xie] S;School of Civil Engineering, University of South China, Hengyang, China<&wdkj&>Key Discipline Laboratory for National Defence of Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, China
摘要：
A zirconium-based metal-organic framework (DUT-69) was fabricated via a hydrothermal synthesis for U(VI) removal in aqueous solutions. Experimental results showed that the maximum adsorption capacity for U(VI) was 362.32 mg center dot g(-1) at 303 K, pH = 6 and initial U(VI) concentration of 80 mg L-1. The adsorption process fit well with the pseudo-second-order kinetic and Langmuir models. Various characterizations indicated that complexation interactions was the central adsorption mechanism and electrostatic was the secondary. The carboxyl, Zr-O, and C-S bonds in the framework participated in the adsorption process. Reusability experiments showed that 80.34% adsorption rate could be maintained after 5 cycles.
关键词：
accidents, nuclear, biological indicators, dose, low, health effects
摘要：
The impact of long-term low-dose radiation on human health has always been a concern. Long-term low-dose gamma radiation causes cells continuous injury and causes chromosomal mutations to greatly increase the chance of cancer. Because it is significant to identify biomarkers for long-term low-dose gamma radiation, we investigate the influence of low dose rate on the gene expressions in the AHH-1 lymphocytes cell line (AHH-1 cells) for long-term irradiation. Different dose rates (7, 14, 26, 34, and 43 μGy h-1) of irradiation from gamma radiation in uranium tailings powder were used to irradiate AHH-1 lymphocytes. We used flow cytometry to test the apoptosis of AHH-1 lymphocytes at different dose rates and irradiation times (7-84 d). It was found that 14 μGy h-1 is the most sensitive dose rate of AHH-1 lymphocyte irradiation. The 7-, 14-, and 21-d (2.4, 4.8, and 7.2 mGy) irradiation groups were sensitive, and the 84-d (28.8 mGy) irradiation group was insensitive to low dose gamma radiation. Microarray analysis was conducted on the significantly differentially expressed genes (p<0.05) in the 2.4, 4.8, 7.2, and 28.8 mGy irradiation groups. We found that TFRC1, SLC3A2, SLC39A8, FTH1, ACSL4, and GPX4 are significant genes with low-dose radiation and were constituents of the ferroptosis signaling pathway. In the range of 0-4.8 mGy radiation dose, the expressions of these genes were downregulated with increasing radiation dose, while in the range of 4.8-28.8 mGy, its expression increased with increasing radiation dose. RT-PCR and Western blot were used to detect the mRNA and protein expression of these genes. The results were consistent with those from microarray analysis. Our findings indicate that expression of the TFRC, SLC3A2, SLC39A, FTH1, ACSL4, and GPX4 genes is sensitive to low-dose radiation, and they are main members of the ferroptosis signaling pathway. Therefore, there is a very important connection between ferroptosis and low-dose radiation, which has become a hot topic in international research. These results can provide reference to the effect of ferroptosis on human health with low-dose radiation.
摘要：
Microbial Induced Calcium Carbonate Precipitation (MICP) has some disadvantages, such as low crystallization conversion rate of calcium carbonate and insufficient strength properties of tailings. In this paper, a modified method combining soft template calcium carbonate mineralization technology with microbial grouting reinforcement technology was proposed. The tailings solidification was studied with the control of nine different concentrations of egg white (0%, 5%, 10%, 15%, 20%, 30%, 40%, 60% and 80%). After 14 days of grouting reinforcement experiment, the results are as follows. (1) The shear strength of tailings was improved remarkably, and the best reinforcement effect was at 5% egg white. Compared with the control group, the effective cohesion of tailings increased by 437.61%. (2) The fitting curve between the content of calcium carbonate in tailings and its cohesion shows that there is an exponential relationship between them. (3) The results of microscopic examination showed that the proportion of columbite-type calcium carbonate increased with the increase of egg white concentration. The corresponding egg white concentration of calcite-type calcium carbonate was 5%. At this time, the maximum particle size could reach 100 mu m. (4) The infrared absorption characteristic curves of the interporous cements of tailings indicate that the changes of crystal form, crystal morphology and particle size of calcium carbonate may be due to the strong interaction between polar groups such as N-H, C-H and C=O in the composition of egg white and calcium carbonate crystal. (5) The bonding, connecting and packaging of fibers in egg white will cause fundamental changes in the bonding mode of tailings. The test results showed that the combination of mineralization regulation of egg white and MICP technology can achieve complementary advantages, which is of great engineering significance for improving the stability and safety of tailings dam. (C) 2020 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society.
摘要：
A particle-packing emanation media consists of ore particles with varying size and shape commonly existing in the stopes and the blind roadways of underground uranium mines, from which exhaled radon poses a health hazard to mining personnel. Dynamic equations of radon release-diffusion-seepage migration in finite-thickness particle-packing emanation media were established in this study based on the individual ore model. Calculation equations for radon exhalation rate and proportion of the media under two different kinds of migration mechanisms (drived by seepage-diffusion or only by seepage) were deduced and the results were utilized to explore the influence of media thickness, diffusion coefficient, and equivalent media particle size on radon exhalation. The results show that radon exhalation rate along the direction of seepage flow first sharply increases, then slightly increases with the equivalent velocity of seepage (dimensionless) increases from 0 to 20, whereas the opposite is the case for the reverse direction of seepage flow radon; the total radon exhalation rate increases with the thickness of media and the seepage velocity increase. The results also show that radon exhalation proportion is significantly influenced by equivalent particle size under a small diffusion coefficient. These findings can be used as references for ventilation design to reduce radon concentration level in the stopes of underground uranium mine.
作者机构：
[刘清; 邓真宁] Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang;Hunan;421001, China;[滑熠龙] Key Discipline Laboratory for National Defence for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;[招国栋] School of Resource & Environment and Safety Engineering, University of South China, Hengyang
作者机构：
[Ding, Dexin; Wang, Huimin; Yuan, Penghui; Hu, Nan; Zhao, Weichao] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Hunan, Peoples R China.;[Ding, Dexin; Wang, Huimin; Yuan, Penghui; Hu, Nan] Hunan Prov Key Lab Green Dev Technol Extremely Lo, Hengyang 421001, Hunan, Peoples R China.;[Long, Dingxin; Zhao, Weichao] Univ South China, Sch Publ Hlth, Hengyang 421001, Hunan, Peoples R China.;[Ding, Dexin] Univ South China, Hengyang 421001, Hunan, Peoples R China.
通讯机构：
[Ding, Dexin] U;Univ South China, Hengyang 421001, Hunan, Peoples R China.
摘要：
To investigate the effects of low-dose gamma irradiation on apoptosis and development of the brain in zebrafish embryos, cumulative 15 mGy doses of gamma rays from a Cs-137 source were used to irradiate zebrafish embryos at 2 h post-fertilization (hpf) for 120 h. Apoptosis of the brain, brain morphological development, cell submicroscopic structure and mRNA expression were analyzed, respectively. Results indicate that after 15 mGy exposure, the apoptosis of zebrafish brain increased, vacuoles appeared in brain tissue, some organdies were damaged and vacuoles appeared locally in brain cells. The mRNA expression level of axin2 was significantly upregulated, and those of frizzled, beta-catenin, camk2, TCF/ LEF and bcl9 were significantly downregulated in brain tissue. These genes are involved in the Wnt signaling pathway. The findings of this work suggest that low-dose radiation may influence the apoptosis and development of the brain in the zebrafish embryo by inhibiting the Wnt signaling pathway. (C) 2020 by Radiation Research Society
通讯机构：
[Ding, Dexin] U;Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.
关键词：
Uranium;Removal;Photoreduction;Wastewater
摘要：
Efficient elimination of U(VI) from uranium wastewater is an urgent task for sustainable nuclear energy and environmental protection. In this study, magnetic graphene oxide decorated graphitic carbon nitride (mGO/g-C3N4) nanocomposite was prepared and used for photocatalytic reduction of U(VI) in wastewater under visible LED light irradiation for the first time. The batch experiments indicated that the mGO/g-C3N4 (mGCN) nanocomposite could efficiently reduce U(VI) under visible LED light, and a high U(VI) extraction capacity of 2880.6 mg/g was obtained with an extraction efficiency of 96.02%. The transmission electron microscopy (TEM) elemental mapping, X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses demonstrated that the soluble U(VI) was immobilized by transforming it to metastudtite ((UO2)O-2 center dot 2H(2)O) by mGCN nanocomposite under visible LED light irradiation. This work indicated that the mGCN is a promising visible light catalyst for treatment of uranium wastewater. (C) 2020 Elsevier Ltd. All rights reserved.
摘要：
The adsorption characteristics of phosphorylated Aspergillus niger (AN-P) for uranium(VI) were studied in this work. The AN-P was successfully prepared by the reaction of Aspergillus niger with phosphorus pentoxide in ice-bath under the catalysis of methanesulphonic acid. AN-P was characterized by FT-IR and SEM-EDS. The effects of pH, contact time, initial U(VI) ions concentration, adsorbent dosage and temperature on the adsorption of U(VI) by AN-P were investigated. The isotherm and kinetic data were accurately described by the Langmuir and pseudo-second-order models, respectively. The calculated thermodynamic parameters indicated that the adsorption of U(VI) by AN-P was an spontaneous and endothermic process. This indicated that the AN-P composite is a promising adsorbent for efficient removal of U(VI) from radioactive wastewater.
摘要：
Microbial grouting reinforcement technology can improve the strength of tailings to a certain extent, but there is still much room for improvement. To balance the adverse effects of the technology to cure the tailings, this paper introduced the mineralization technology of soft template into the microbial induced calcium carbonate precipitation (MICP), and carried out the experiments on microbial grouting to strengthen the tailings under the control of organic matrix. The results of aqueous solution test showed that the organic matrix can significantly regulate the structural characteristics of calcium carbonate. When the added organic matrix is egg white protein with a volume fraction of 20%, the contribution to the conversion rate of calcium ions in the reaction solution was the largest, and the concentration of calcium ions in the solution at 20 h is reduced by about 83.72% compared with the control group. In the solidification test of tailings, as the egg white concentration increased, the curing unevenness of the tailings was further aggravated. When the egg white volume fraction is 5%, the strength improvement effect of the tailings was the best and the dilatancy characteristic was the most significant. At the same time, the calcium carbonate produced are mostly large-sized calcite, and the corresponding formation amount, cohesive force and internal friction angle are 16.01%, 131.98 kPa and 42.7 degrees, respectively. The study showed that mineralization technology of soft template can promote the MICP technology, which provides a new method for the reinforcement of tailings dam. (C) 2020 The Author(s). Published by Elsevier Ltd.
作者机构：
[莫官海; 谢水波; Zeng, Taotao; 刘迎九] Hunan Province Key Laboratory of Pollution Control and Resource Reuse Technology, University of South China, Hengyang;Hunan;421001, China;Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang;[莫官海; 谢水波; Zeng, Taotao; 刘迎九] Hunan
