期刊：
Journal of Radioanalytical and Nuclear Chemistry,2023年332(11):4427-4439 ISSN：0236-5731
通讯作者：
Xie, D
作者机构：
[Yang, Xiaomin] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Xie, D; Xie, Dong; Wu, Hui; Yang, Xiaomin] Natl & Local Joint Engn Res Ctr Airborne Pollutant, Hengyang 421001, Peoples R China.;[Xie, D; Xie, Dong; Wu, Hui] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
通讯机构：
[Xie, D ] N;Natl & Local Joint Engn Res Ctr Airborne Pollutant, Hengyang 421001, Peoples R China.;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
摘要：
The effective capture of iodine vapour, a potential threat of environment and human health, is crucial for efficiently managing nuclear waste gases. Herein, the adsorption property of iodine vapour on modified activated carbon fibers was investigated using adsorption experiment and simulation methods, to explain the adsorption mechanism at different scales. Preliminary results hint that the ideal adsorbent should have lower density, higher adsorption coefficient and taller poriness, and more pores between 1.6 and 1.9 nm. Compared with KOH modification, microwave modification can effectively improve the performance of activated carbon fibers for capturing iodine vapour.
作者机构：
[Chen, Zhenfu; Tao, Qiuwang; Jin, Dan; Huang, Xinyun; Wu, Dan] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Chen, Zhenfu; Tao, Qiuwang; Jin, Dan; Huang, Xinyun; Wu, Dan] Univ South China, Key Lab High Performance Special Concrete Hunan Pr, Hengyang 421001, Peoples R China.;[Chen, Zhenfu; Tao, Qiuwang; Huang, Xinyun] Univ South China, Key Lab High Performance Concrete China Nucl Ind, Hengyang 421001, Peoples R China.;[Xie, Liping] China Nucl Ind 22ND Construct Co Ltd, Yichang 443101, Peoples R China.
通讯机构：
[Zhenfu Chen] K;Key Laboratory of High-Performance Special Concrete in Hunan Province, University of South China, Hengyang 421001, China<&wdkj&>School of Civil Engineering, University of South China, Hengyang 421001, China<&wdkj&>Key Laboratory of High-Performance Concrete in China Nuclear Industry, University of South China, Hengyang 421001, China<&wdkj&>Author to whom correspondence should be addressed.
关键词：
high temperatures;multiple heating;magnetite shielded concrete;splitting tensile strength;gamma-ray shielding properties
摘要：
Radiation shielding concrete is one of the most used materials in the construction of nuclear power plants and will be subjected to high temperatures for a long time during its service life. This study aims to investigate deterioration of radiation shielding concrete with multiple heating at different temperatures. A microwave oven was used as a heating apparatus to simulate irradiation, and 200, 300, and 400 degrees C were selected as experimental cycle temperatures. The apparent characteristics, mass loss, splitting tensile strength, and gamma ray shielding properties of the commonly used magnetite shielding concrete were investigated. The results showed that the splitting tensile strength and gamma shielding performance of concrete were dramatically reduced at first heating. Then, as the heating times increased, the splitting tensile strength and gamma shielding properties of the concrete continued to deteriorate, and the higher the increase in heating temperature, the more severe the deterioration of the concrete. During the service period of radiation shielded concrete, the magnitude of temperature under the service conditions will affect the deterioration degree of concrete, and the continuous change of temperature will continuously lead to the deterioration of concrete.
摘要：
A new persimmon tannin-modified graphene oxide/chitosan microsphere (PGC) was prepared by the mixed crosslinking method, and the effective adsorption behavior of U(VI) in an aqueous solution was discussed. The study shows that at the temperature of 30 & DEG;C, pH of 5, time of 120 min, and the an initial uranium concentration of 10.00 mg/L, the maximum adsorption capacity of PGC microspheres for U(VI) reached 199.13 mg/g, with a removal rate of 98.2%. The adsorption process of U(VI) by PGC microspheres conforms to the pseudo-second-order kinetic model and the Freundlich isothermal adsorption model. The adsorption mechanism of U(VI) by PGC microspheres is electrostatic interaction and chelation reaction. Meanwhile, PGC microspheres have excellent adsorption selectivity and recycling, and they have a good adsorption effect in the uranium treatment of rare earth real wastewater. Therefore, PGC microspheres can be used as a promising material to treat uranium-containing rare earth wastewater.
作者机构：
[Li, Ming; Zhou, Yi-Liang; Li, M; He, Qi] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[He, Lin] China Nucl Ind Huaxing Construct Co Ltd, Nanjing, Peoples R China.;[Dai, Hong-Liang] Hunan Univ, State Key Lab Adv Design & Mfg Vehicle Body, Changsha 410082, Peoples R China.
通讯机构：
[Li, M ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词：
Nonlinear frequency ratio;CFRR;Sandwich doubly-curved shallow shell;Hygrothermal environment;Microcapsule coating
摘要：
In this paper, the nonlinear vibration characteristics and response of laminated carbon fiber reinforced resin (CFRR) doubly-curved shallow shell with a porous microcapsule coating under hygrothermal environment is investigated. Based on the first-order shear deformation theory, the nonlinear equations of motion are obtained by using Hamilton's principle, which are solved by utilizing the direct integration method and Runge-Kutta method. The effect of temperature and moisture, geometric parameters of microcapsules, geometric parameters of the shell, laying angle for carbon fiber and porosity of coating matrix are considered. Through numerical examples, it is found that temperature, moisture, length of edges, laying angle for carbon fiber and porosity of coating matrix have a positive effect on the dimensionless nonlinear frequency ratio, but negative effect on the dimensionless linear and nonlinear natural frequency of the shell. In addition, temperature, moisture, length of edges, laying angle for carbon fiber and porosity of coating matrix are proportional to the dimensionless nonlinear amplitude of the shell.
摘要：
A magnesium aluminum bimetallic organic framework derivative (MgAl-DHBDC/LDH composite) was prepared by etching MgAl bimetallic MOF template and used to remove U(VI) in aqueous solution. Compared to MgAl-DHBDC, the stability, dispersibility and removal ratio of U(VI) with MgAl-DHBDC/LDH were improved significantly over a wide pH range. The adsorption of uranium by MgAl-DHBDC/LDH was mainly multilayer physical adsorption, and the adsorption process was a spontaneous endothermic process. Moreover, the removal ratio of U(VI) by the MgAl-DHBDC/LDH composite remained above 90% after 4 cycles, indicating good regeneration performance. The MgAl-DHBDC/LDH composite shows great potential in the remediation of radionuclide uranium wastewater.
通讯机构：
[Gang Wang] K;Key Laboratory of Geotechnical and Structural Engineering Safety of Hubei Province, School of Civil Engineering, Wuhan University, Wuhan, China<&wdkj&>School of Civil Engineering, Shaoxing University, Shaoxing, China
关键词：
Rockburst intensities;Rockburst prediction;Strain rockburst;Stress gradient;Stress–strength ratio
摘要：
High temperature can cause serious damage to building structures, so it is important in order to re-evaluate the residual properties of radiation shielding concrete (RSC) exposed to elevated temperatures for ensuring security of medical, industrial and defense building structures. Thus, the deterioration of the mechanical, gamma-ray shielding properties and acoustic emission character-istics of barite concrete (BC) and magnetite concrete (MC) exposed to elevated temperatures were studied. Research indicated that the performance of aggregates played a crucial role in the thermal stability, residual physical and mechanical properties of concrete exposed to elevated temperatures. BC was subjected from bursting and even spalling at 300 degrees C, while its physical and mechanical properties deteriorated drastically. However, MC still had favorable integrity and relatively high residual mechanical properties at 800 degrees C. The maximum deterioration tempera-ture of BC exposed to elevated temperatures occurred at about 300 degrees C, while that of MC occurred at 450-600 degrees C. The degradation of the gamma-ray shielding properties of RSC exposed to elevated temperatures was significantly lower than its mechanical properties.
期刊：
Environmental Science and Pollution Research,2023年30(7):18156-18167 ISSN：0944-1344
通讯作者：
Yang, Huaming
作者机构：
[Liu, Hongjuan; Yang, Huaming] China Univ Geosci, Engn Res Ctr Nanogeomat, Minist Educ, Wuhan 430074, Peoples R China.;[Min, Zefu; Liu, Hongjuan; You, Hang; Wang, Xi; Li, Yongjiang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Xie, Shuibo] Univ South China, Key Discipline Lab Natl Def Biotechnol Uranium Mi, Hengyang 421001, Peoples R China.;[Xie, Shuibo; Liu, Yingjiu] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reu, Hengyang 421001, Peoples R China.;[Yang, Huaming] China Univ Geosci, Key Lab Funct Geomat China Nonmet Minerals Ind, Wuhan 430074, Peoples R China.
通讯机构：
[Yang, Huaming] E;Engineering Research Center of Nano-Geomaterials of Ministry of Education, China University of Geosciences, Wuhan, 430074, People's Republic of China. hm.;Key Laboratory of Functional Geomaterials in China Nonmetallic Minerals Industry, China University of Geosciences, Wuhan, 430074, People's Republic of China. hm.
通讯机构：
[Shuibo Xie] S;School of Civil Engineering, University of South China, Hengyang, People’s Republic of China<&wdkj&>Key Discipline Laboratory for National Defence of Biotechnology in Uranium Mining and Hydrometallurgy, University of South China, Hengyang, People’s Republic of China
摘要：
To efficiently remove U(VI) from aqueous solutions, porous polyvinyl alcohol/carboxylated carbon nanotubes/sodium alginate (PPCS) hydrogel microspheres were prepared using the physical cross-linking method. The successful formation of highly porous PPCS hydrogel microspheres was confirmed by SEM and BET. Moreover, PPCS hydrogel microspheres were recovered from aqueous solutions more easily than carbon nanotubes. The main mechanism of PPCS for U(VI) removal may be the chelation of hydroxyl and carboxyl groups. PPCS may be a promising and recyclable adsorbent for uranium extraction.
期刊：
Environmental Science and Pollution Research,2023年30(20):57771-57787 ISSN：0944-1344
通讯作者：
Guanhai Mo
作者机构：
[Mo, Guanhai] Univ South China, Sch Civil Engn, Dept Water Engn & Sci, Hengyang 421001, Peoples R China.;[Xiao, Jiang] South China Univ Technol, Sch Environm & Energy, Guangzhou 510006, Peoples R China.;[Gao, Xiang] Powerchina Zhongnan Engn Corp Co Ltd, Changsha 410000, Peoples R China.
通讯机构：
[Mo, Guanhai] D;Department of Water Engineering and Science, School of Civil Engineering, University of South China, Hengyang, 421001, People's Republic of China.
摘要：
Electrocatalytic oxidation is commonly restricted by low degradation efficiency, slow mass transfer, and high energy consumption. Herein, a synergetic electrocatalysis system was developed for removal of various drugs, i.e., atenolol, florfenicol, and diclofenac sodium, as well as actual pharmaceutical wastewater, where the newly-designed single-atom Zr embedded Ti(4)O(7) (Zr/Ti(4)O(7)) and hierarchical CuFe(2)O(4) (CFO) microspheres were used as anode and microelectrodes, respectively. In the optimal reaction system, the degradation efficiencies of 40mg L(-1) atenolol, florfenicol, and diclofenac sodium could achieve up to 98.8%, 93.4%, and 85.5% in 120min with 0.1g L(-1) CFO at current density of 25mA cm(-2). More importantly, in the flow-through reactor, the electrooxidation lasting for 150min could reduce the COD of actual pharmaceutical wastewater from 432 to 88.6mg L(-1), with a lower energy consumption (25.67kWh/m(3)). Meanwhile, the electrooxidation system maintained superior stability and environmental adaptability. DFT theory calculations revealed that the excellent performance of this electrooxidation system could be ascribed to the striking features of the reduced reaction energy barrier by single-atom Zr loading and abundant oxygen vacancies on the Zr/Ti(4)O(7) surface. Moreover, the characterization and experimental results demonstrated that the CFO unique hierarchical structure and synergistic effect between electrodes were also the important factors that could improve the system performance. The findings shed light on the single-atom material design for boosting electrochemical oxidation performance.
摘要：
Anchors constitute a common form of structural support in geotechnical engineering. Precise identification of ultra-early-stage (UES) anchoring quality is crucial to ensure the integrity of the secondary lining. To address grout defects in the UES of anchors, a calculation method for UES anchor wave velocity was introduced. Indoor experiments and numerical simulations were conducted for non-destructive testing (NDT) of anchors in the UES, analyzing time-domain waveform characteristics and wave velocity variations. A method for identifying grout defects in the UES of anchors was proposed. The results indicate that the proposed wave velocity calculation method offers a more precise estimation of UES wave velocity for anchors compared to the traditional approach. This enhancement enables a more precise evaluation of the development of solid phases in the anchoring medium. As the solid phase develops, the wave velocity and first wave amplitude of the anchor gradually decline, while the response time of the bottom reflection increases. Grout defects lead to amplified amplitudes in both time-domain and frequency-domain signals, accompanied by a heightened occurrence of peaks in the frequency domain. The waveform distortion region before the bottom reflection is caused by grout defects. In the time-domain signals of defective anchors, a waveform distortion region is observed before the bottom reflection. By assessing the magnitude of the absolute value of the ratio between the amplitude of characteristic reflection points within the distortion region and the amplitude of the first wave, effective identification of grout defects in the UES of anchors can be accomplished.
期刊：
Chemical Engineering Journal,2023年465:142730 ISSN：1385-8947
通讯作者：
Zhou, Shuai(zs402606665@126.com)
作者机构：
[Zhou, Shuai; Duan, Yi; Xiang, Chao; Tang, Zhenping] Univ South China, Hunan Prov Key Lab Pollut Control & Resources Reus, Hengyang 421001, Peoples R China.;[Gao, Yuanyuan; Hua, Yilong; Zhou, Shuai; Wei, Fuxing; Zhu, Feiyu; Jiang, Tianyun; Tang, Zhenping] Univ South China, Hunan Prov Key Lab Rare Met Minerals Exploitat & G, Hengyang 421001, Peoples R China.;[Wang, Yayi] Tongji Univ, Coll Environm Sci & Engn, State Key Lab Pollut Control & Resources Reuse, Siping Rd, Shanghai 200092, Peoples R China.
通讯机构：
[Shuai Zhou] H;[Yayi Wang] S;State Key Laboratory of Pollution Control and Resources Reuse, College of Environmental Science and Engineering, Tongji University, Siping Road, Shanghai 200092, China<&wdkj&>Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang 421001, China<&wdkj&>Hunan Province Key Laboratory of Rare Metal Minerals Exploitation and Geological Disposal of Wastes, University of South China, Hengyang 421001, China
摘要：
Although oxygen-containing functional groups generated during unavoidable aging play a key role in improving the adsorption performance of heavy metals by microplastics (MPs), little is known about the contribution of such groups to the interactions between highly toxic radioactive heavy metals and aged MPs. Here, we used a combination of batch experiments and density functional theory calculations to examine the effects and mechanisms of aging and the produced oxygen-containing functional groups, i.e., C═O, –OH, phenolic hydroxyl (–OHm), and –COOH, on the adsorption behavior of representative radionuclide uranium (U) on polystyrene (PS) MPs. The kinetic experimental results showed that the amount of U adsorption by the aged PS MPs was significantly higher than that of virgin PS MPs (P < 0.05). Binding-energy and thermodynamic data indicated that the affinity of PS MPs to a typical U species, i.e., uranyl, followed the order of PS═O–OHm > PS═O > PS–COOH > PS–OH > PS–OHm > virgin PS. Characterization and surface potential analyses demonstrated that the electronegative oxygen atoms in oxygen-containing functional groups in the aged PS MPs increased along with the aging time, and could serve as potential sites for electrostatic interactions with uranyl. Intramolecular interaction calculations confirmed that hydrogen bonding by oxygen-containing functional groups could strengthen the interactions between uranyl and aged PS MPs via electrostatic and polarization effects. Our findings provide an in-depth understanding of the role of aging in U adsorption by MPs, which is critical for assessing the fate of coexisting radionuclides and MPs in the environment, and their associated risks.
通讯机构：
[Taotao Zeng] H;Hunan Province Key Laboratory of Pollution Control and Resources Reuse Technology, University of South China, Hengyang, 421001, Hunan, China
摘要：
The use of modified biochar for the remediation of heavy metal (HM) has received much attention. However, the immobilization mechanism of biochar to multiple HMs and the interaction of different forms of HMs with microorganisms are still unclear. K(2)HPO(4)-modified biochar (PBC) was produced and used in a 90-days immobilization experiment with soil collected from a typic lead-zinc (Pb-Zn) mining soil. Incubation experiments showed that PBC enhanced the transformation of Cd, Pb, Zn and Cu from exchangeable (Ex-) and/or carbonate-bound forms (Car-) to organic matter-bound (Or-) and/or residual forms (Re-). After scanning electron microscopy-energy dispersive X-ray spectrometer (SEM-EDS), X-ray diffractometry (XRD), fourier transform infrared (FTIR), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS) analysis, the mechanisms of HM immobilization by PBC were proposed as precipitation (PO(4)(3-), HPO(4)(2-), OH(-) and CO(3)(2-)), electrostatic attraction, complexation (-COOH, -OH and R-O-H) and the indirect roles of soil parameter variations (pH, moisture and microbial community). Microbial community analysis through high-throughput sequencing showed that PBC reduced bacterial and fungal abundance. However, addition of PBC increased the relative proportions of Proteobacteria by 15.04%-42.99%, Actinobacteria by 4.74%-22.04%, Firmicutes by 0.76%-23.35%, Bacteroidota by 0.16%-12.34%, Mortierellomycota by 4.00%-9.66% and Chytridiomycota by 0.10%-13.7%. Ex-Cd/Pb/Zn, Car-Cd/Zn and Re-Cd/Pb/As were significantly positively (0.001<P≤0.05) correlated with bacterial phyla of Crenarchaeota and Methylomirabilota, and Re-Cu and Ex-/Car-/Fe-Mn oxide-bound (Fe-Mn-)/Or-As were significantly positively correlated (0.001<P≤0.05) with the bacterial phyla of Proteobacteria and Bacteroidota. While Car-Cd/Zn and Re-Pb/As were positively correlated (0.01<P≤0.05) with fungal phyla of Ascomycota, Glomeromycota, Kickxellomycota, Basidiomycota and Mucoromycota. The bacterial network contained more complex interactions than the fungal network, suggesting that bacteria play a larger role in HMs transformation processes. The results indicate that PBC is an effective agent for the remediation of HMs polluted soil in Pb-Zn mining areas.
作者机构：
[Yang, Shijiao; Fan, Junwei] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Deng, Bo; Fan, Junwei; Deng, B; Sun, Bing] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Liu, Taoying] Cent South Univ, Sch Resources & Safety Engn, Changsha 410012, Peoples R China.
通讯机构：
[Deng, B ] U;Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.
关键词：
slope engineering;lattice beam;load distribution method;Winkler foundation model
摘要：
As a new type of retaining structure, lattice beams with tie-back anchor cables have been increasingly used in slope reinforcement and have achieved improved prevention effects. However, the simplified load distribution method (SLDM) at the node, which is the theoretical basis of internal force analysis for lattice beams, is not perfect at present. An alternative new load distribution method (NLDM) at the node based on the force method for the lattice beam was therefore introduced in this paper. Taking into account the loads acting on other nodes of the beams in both directions and according to the static equilibrium condition and deformation compatibility condition at the nodes, NLDM assigns the loads acting on the nodes to the cross beams and vertical beams, respectively, by constructing and solving a system of linear equations. In order to verify the superiority of NLDM, a case of slope reinforced by a lattice beam was introduced in this paper, and the load distribution of the nodes under the design condition was carried out based on both methods. Then, the deflections at the nodes of the lattice beam resting on the Winkler foundation, loaded with the known loads, were analyzed by the superposition method. The results of the deformation analysis showed that the deflections at the same nodes of the beams in both directions based on NLDM were almost equal, thus demonstrating the superiority of NLDM in terms of deformation compatibility. In addition, a comparative analysis of the theoretical bending moments of the lattice beam under the design and the actual working conditions based on both methods was also carried out. The results of the bending moment analysis showed that the bending moments of the cross beam differed significantly in the middle third of the beam length, while the bending moments of the vertical beams differed significantly at the beam sections where the maximum bending moments are located, and the theoretical bending moments under the actual working condition were in relatively good agreement with the measured values. Consequently, NLDM for the lattice beam was self-consistent in terms of the deformation compatibility at the node, and therefore the introduction of this new method provides an important theoretical basis for the accurate internal force analysis of lattice beams.
摘要：
The beneficial reuse of cement-treated waste sludge in construction sector is an intractable challenge in the context of sustainable development. To exploit the potential of magnesium oxychloride cement (MOC) as cementing binder in substitution for Portland cement, various inorganic/organic additives are imported to overcome the key defect of MOC – instability in water and improve the water resistance of MOC solidified sludge. To achieve this goal, the mechanical and microstructural studies by compressive strength, water immersion, shear strength, compressibility, X-ray diffraction and scanning electron microscopy tests are comprehensively examined. Key outcomes reveal that: (i) Compressive strength, shear strength and water resistance of MOC solidified sludge can be significantly improved by a reasonable dosage of chemical additives, especially for phosphoric acid (3%), citric acid (4%) and urea–formaldehyde resin (12%), (ii) Shear strength versus normal stress relationship can be well represented by the approximately linear function, while cohesion and internal friction angle show an upward tendency with standard curing age and later a downward trend with water immersion period, (iii) Yielding stress exhibits a tendency of first rise and then fall with curing age, but compression index has a trend of first decline and then increase, and (iv) Lamellar Mg(OH)2, rod-like/plate-like phase 5 and phase 3 are identified as the major hydrated products conducive to the excellent performance of additive-modified MOC solidified sludge. A better understanding of the improvement of chemical additives on MOC solidified sludge is helpful to synthesize MOC that exhibits properties suitable for application as a cementing binder.
期刊：
Journal of Radioanalytical and Nuclear Chemistry,2023年332(6):1743-1754 ISSN：0236-5731
通讯作者：
Chunning Chen<&wdkj&>Jinxiang Liu
作者机构：
[Zhu, Kaihao] Univ South China, Sch Civil Engn, Hunan Prov Key Lab Pollut Control & Resources Tech, Hengyang, Peoples R China.;[Wang, Shuiyun; Peng, Lin; Chen, Chunning; Liu, Jinxiang; Zhu, Kaihao; Xian, Han] Univ South China, Sch Civil Engn, Hengyang, Peoples R China.
通讯机构：
[Chunning Chen; Jinxiang Liu] S;School of Civil Engineering, University of South China, Hengyang, China<&wdkj&>School of Civil Engineering, University of South China, Hengyang, China
摘要：
A molybdenum disulfide/biochar (MoS2/BC) composite was synthesised by a facile hydrothermal process and used for the adsorption of U(VI) from aqueous solution through batch experiments. Results showed that MoS2/BC exhibit a saturated adsorption capacity of 451.3 mg/g at pH = 5, t = 60 min, T = 298 K, M/V = 0.02 g/L, C-U(VI) = 10 mg/L, which was higher than that of MoS2 and biochar. The process of MoS2/BC for U(VI) adsorption was better simulated via the pseudo-second-order kinetic model (R-2 = 0.999) and Langmuir isotherm model (R-2 = 0.999). The adsorption mechanism of U(VI) includes chemical adsorption, electrostatic attraction, surface complexation of oxygen-containing functional groups, cation-pi bond and coordination of S group. After five adsorption-desorption experiments, the elimination rate remained above 80%.
