Strontium Ion Removal From Artificial Seawater Using a Combination of Adsorption With Biochar and Precipitation by Blowing CO2 Nanobubble With Neutralization
作者:
Guo, Yixuan;Hong Nhung, Nguyen Thi;Dai, Xiang;He, Chunlin;Wang, Youbin;...
期刊:
Frontiers in Bioengineering and Biotechnology ,2022年10:819407 ISSN:2296-4185
通讯作者:
Fujita, T
作者机构:
[He, Chunlin; Fujita, Toyohisa; Wang, Youbin; Guo, Yixuan; Dai, Xiang; Hong Nhung, Nguyen Thi; Fujita, T] Guangxi Univ, Sch Resources Environm & Mat, Nanning, Peoples R China.;[Wei, Yuezhou] Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;[Fujita, Toyohisa; Fujita, T] Guangxi Univ, Sch Chem & Chem Engn, Nanning, Peoples R China.
通讯机构:
[Fujita, T ] G;Guangxi Univ, Sch Resources Environm & Mat, Nanning, Peoples R China.;Guangxi Univ, Sch Chem & Chem Engn, Nanning, Peoples R China.
关键词:
Biochar1;Adsorption2;Strontium radionuclide3;Seawater4;CO2 nanobubbles5
摘要:
While enjoying the convenience of nuclear energy development, the environmental contamination by radionuclide leakage is of significant concern. Because of its cost-effectiveness and environmental friendliness, biochar has attracted a lot of attention in the field of radioactive water treatment. Herein, a novel teak peel modified biochar (labeled as PMBN3) was prepared and applied to remove strontium from artificial seawater. The characterisation of the prepared PMBN3 showed it contains numerous oxygen-containing functional groups (i.e. carboxyl and hydroxyl groups), laminar morphology, mesoporous structure, large specific surface area. PMBN3 exhibited great advantages in Sr(II) adsorption, such as rapid adsorption kinetics (<1h for equilibrium) and superior reusability. The adsorption of strontium by biochar is consistent with pseudo-second order and internal diffusion kinetic models. Among the four types of adsorption isotherms, the Freundlich isotherm showed the best fit with R2 > 0.98. The calculated thermodynamic parameters indicate that strontium adsorption on biochar occurs exothermically and spontaneously. Furthermore, for efficient removal of Sr(II), CO2 nanobubbles were blown into artificial seawater to precipitate the interfering metal ions, and followed by the adsorption of PMBN3 towards residual metal ions with the removal rate of Sr(II) over 99.7%. Finally, mechanistic studies have shown that the strontium adsorption process by PMBN3 is a multiple adsorption mechanism consisting of ion exchange between H+ (from -OH and -COOH) and Sr(II), and weak intermolecular forces between Sr(II) and the PMBN3 adsorbent. This study creatively combines chemisorption and nanobubble precipitation for strontium removal, which provides great reference value and guidance for environmental remediation. Copyright © 2022 Guo, Hong Nhung, Dai, He, Wang, Wei and Fujita.
语种:
英文
展开
Numerical investigation of ECCD under the CFETR concept design parameters
作者:
He, L. H.;Zheng, P. W.;Zheng, Z. H.;Chen, J. L.;Yu, T.
期刊:
Fusion Engineering and Design ,2022年182:113236 ISSN:0920-3796
通讯作者:
Zheng, P.W.(pwzheng@usc.edu.cn)
作者机构:
[He, L. H.; Zheng, P. W.; Chen, J. L.; Yu, T.] Univ South China, Coll Nucl Sci & technol, Hengyang 421001, Hunan, Peoples R China.;[Zheng, Z. H.] Southwestern Inst Phys, Chengdu 610041, Sichuan, Peoples R China.;[Chen, J. L.] Chinese Acad Sci, Inst Plasma Phys, Hefei 230031, Anhui, Peoples R China.
通讯机构:
[P.W. Zheng; T. Yu] C;College of nuclear science and technology, University of South China, Hengyang, Hunan 421001, China<&wdkj&>College of nuclear science and technology, University of South China, Hengyang, Hunan 421001, China
关键词:
CFETR;EC waves;ECCD;Current drive efficiency
摘要:
RF power in the electron cyclotron (EC) frequency range is planned to be injected to the plasmas of China Fusion Engineering Test Reactor (CFETR). Numerical investigation for electron cyclotron current drive (ECCD) is performed under the parameters of the latest/final version of the CFETR concept design (R = 7.2 m, a = 2.2 m, BT = 6.5 T). The TORAY-GA ray-tracing code is used to optimize frequency and launcher ports of EC waves. It is found that both 240 GHz and 250 GHz EC waves can meet the desired current drive demand in the target radial region (ρ ≤ 0.40). The 240 GHz EC wave is the optimum candidate. It can be launched either from equatorial launcher (EL) port, upper launcher (UL) port or top launcher (TL) port. EC waves with frequency equal to or larger than 250 GHz will be suffered strong parasitic second harmonic absorption if it is launched from EL port. Except for 250 GHz wave launched from EL port, ECCD efficiency increases with the increasing of EC frequency in the range of 190 ∼ 250 GHz. The maximum CD efficiency γCD [tbnd] n20RIec/Pin can reach 0.3 taking account for improvement of the CD efficiency about 20% enhanced by momentum conserving correction in the central radial region (ρ ≤ ∼ 0.20), either by 240 GHz EL-ECCD or 240/250 GHz UL-ECCD launching from (Ri, Zi) = (8.2, 4.5) m. Large toroidal incident angle α is needed for higher EC frequency to obtain an efficient CD efficiency. Necessary and sufficient conditions for successful and effective TL-ECCD are given. Compared to UL-ECCD, TL-ECCD does not significantly improve the efficiency of ECCD in the mid-radius region (ρ = 0.4 ∼ 0.6). Most cases of TL-ECCD significantly improve the efficiency of ECCD in the mid-radius region compared with EL-ECCD, but some cases does not. It is different from the results of previous theoretical simulations, in which TL-ECCD shows significantly improve ECCD efficiency than EL launcher. These findings are of significance for design of an efficient ECCD system under the CFETR design parameters. © 2022 Elsevier B.V.
语种:
英文
展开
Oxidation behaviour of interlocking SiC–Si coating for graphite prepared by preoxidation and gaseous silicon infiltration process
作者:
Xie, Xiangmin;Su, Zhean;Tang, Xian;Liao, Jingjing;Tong, Kai;...
期刊:
Ceramics International ,2022年48(14):20914-20922 ISSN:0272-8842
通讯作者:
Su, Zhe'an(suza@csu.edu.cn);Tang, Xian(xiantang@usc.edu.cn)
作者机构:
[Tang, Xian; Xie, Xiangmin; Liao, Jingjing] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Su, Zhean; Xie, Xiangmin; Tong, Kai; Huang, Qizhong] Cent South Univ, Natl Key Lab Sci & Technol Natl Def High strength, Changsha 410083, Peoples R China.;[Yang, Cheng] Hunan Changyu Sci & Technol Dev Co Ltd, Changsha 410600, Peoples R China.
通讯机构:
National Key Laboratory of Science and Technology for National Defence on High-strength Structural Materials, Central South University, Changsha, China
关键词:
Gaseous silicon infiltration;Interlocking structure;Oxidation behaviour;Preoxidation;SiC–Si coating
摘要:
An interlocking SiC–Si coating on graphite was fabricated by a method combining preoxidation and gaseous silicon infiltration processes. The effect of preoxidation time on the microstructures and oxidation behaviour of the coating was investigated. After preoxidation of graphite at 900 °C for 10 min, the thickness of the as-obtained SiC–Si coating increased from 35 μm to 80 μm, and the penetration depth of the SiC–Si phase was up to several hundred microns. The isothermal oxidation test at 1500 °C suggested that the mass loss of coated graphite decreased from 5.42% after 6 h to 1.28% after 110 h, and the 15 times thermal shock test between 1500 °C and room temperature suggested that the mass loss decreased from 13.20% to −0.34% because of preoxidation. The improved oxidation performance is ascribed to the fact that the interlocking structure of the SiC–Si coating alleviates crack propagation during oxidation, and a large amount of glassy SiO2 produced on the thick SiC–Si layer migrates and seals the defects in the coating. It is believed that the construction of an interlocking structure offers a technological basis to produce oxidation protective coatings for carbon-based materials in high-temperature applications. © 2022 Elsevier Ltd and Techna Group S.r.l.
语种:
英文
展开
Kinetics and Mechanism of Catalytic Reduction of U(VI) with Hydrazine on Platinum Catalysts in Nitric Acid Media
作者:
Zhang, Xiao-teng;Hao, Shuai;Tang, Fei-fei;Li, Bin;Zhou, Xian-ming;...
期刊:
化学物理学报(英文版) ,2022年35(5):813-822 ISSN:1674-0068
通讯作者:
Xia, Liang-Shu(2000000476@usc.edu.cn)
作者机构:
[Hao, Shuai; Zhang, Xiao-teng; Xia, Liang-shu; Tang, Fei-fei] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Li, Bin; Zhou, Xian-ming; Liu, Li-sheng] China Inst Atom Energy, Inst Radiat Chem, Beijing 102413, Peoples R China.
通讯机构:
[Liang-shu Xia] S;School of Nuclear Science and Technology, University of South China , Hengyang 421001, China
关键词:
Uranium;Reaction kinetics;Electron spin resonance;Hydrazine;Density functional theory
摘要:
The kinetics of U(IV) produced by hydrazine reduction of U(VI) with platinum as a catalyst in nitric acid media was studied to reveal the reaction mechanism and optimize the reaction process. Electron spin resonance (ESR) was used to determine the influence of nitric acid oxidation. The effects of nitric acid, hydrazine, U(VI) concentration, catalyst dosage and temperature on the reaction rate were also studied. In addition, the simulation of the reaction process was performed using density functional theory. The results show that the influence of oxidation on the main reaction is limited when the concentration of nitric acid is below 0.5 mol/L. The reaction kinetics equation below the concentration of 0.5 mol/L is found as: -dc(UO22+)/dt=kc0.5323(UO22+)c0.2074(N2H5+)c-0.2009(H+). When the temperature is 50 °C, and the solid/liquid ratio r is 0.0667 g/mL, the reaction kinetics constant is k=0.00199 (mol/L)0.4712/min. Between 20 °C and 80 °C, the reaction rate gradually increases with the increase of temperature, and changes from chemically controlled to diffusion-controlled. The simulations of density functional theory give further insight into the influence of various factors on the reaction process, with which the reaction mechanisms are determined according to the reaction kinetics and the simulation results. © 2022 Chinese Physical Society.
语种:
英文
展开
Research on core power maximization method of natural circulation lead-bismuth cooled fast reactor
作者:
Xiao, Yingjie;Yang, Junkang;Zhao, Pengcheng;Yu, Tao;Liu, Zijing
期刊:
Frontiers in Energy Research ,2022年10:961547 ISSN:2296-598X
通讯作者:
Zhao, Pengcheng(zpc1030@mail.ustc.edu.cn);Yu, Tao(taoyu0626@163.com)
作者机构:
[Liu, Zijing; Yang, Junkang; Xiao, Yingjie; Zhao, Pengcheng; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang, Hunan, Peoples R China.;[Zhao, Pengcheng] Nucl Power Inst China, Sci & Technol Reactor Syst Design Technol Lab, Chengdu, Sichuan, Peoples R China.
通讯机构:
[Zhao, P.; Yu, T.] S;School of Nuclear Science and Technology, Hunan, China
关键词:
Lead-bismuth reactor;Maximum neutronic power;natural circulation;Quasi-static reactivity balance approach;SPALLER-100
摘要:
To improve the inherent safety and cost-effectiveness of lead-bismuth cooled fast reactors, the SPALLER-100 reactor designed by the University of South China has been selected as the research object to determine the maximum power it can produce. This is a multi-objective, complex, multi-dimensional, nonlinear, and constrained optimization problem. To maintain the transportability, material durability, and long-term operation stability of the reactor core and ensure safety under accident conditions, three steady-state limitations and three accident limitations are proposed. The platform used to calculate the maximum neutronic power produced by the reactor at different core heights has been built using Latin hypercube sampling and the Kriging proxy model. Meanwhile, the cooling power of the reactor at different core heights is calculated by considering its natural circulation capacity. Finally, a design scheme is obtained that meets the requirements of neutronic and thermal-hydraulic assessments, while producing maximum power. Consequently, during the entire life-cycle of SPALLER-100, a safety analysis of three typical accident scenarios (unprotected loss of heat sink, unprotected transient over power, and unprotected coolant inlet temperature undercooling) is performed using a Quasi-Static Reactivity Balance (QSRB) approach. The results show that the platform used to calculate the maximum neutronic power exhibits high accuracy, and that the design scheme with maximum power is safe and economical. Overall, this study can provide reference ideas for designing natural circulation reactors that can maximize power output. Copyright © 2022 Xiao, Yang, Zhao, Yu and Liu.
语种:
英文
展开
Research on multi-objective optimization method for flow distribution of natural circulation reactor during its life-cycle
作者:
Zhu, Enping;Chen, Qi;Zhao, Pengcheng;Zhao, Yanan;Sun, Yumeng;...
期刊:
Annals of Nuclear Energy ,2022年176:109266 ISSN:0306-4549
通讯作者:
Zhao, Pengcheng(zpc1030@mail.ustc.edu.cn)
作者机构:
[Liu, Zijing; Sun, Yumeng; Chen, Qi; Zhu, Enping; Zhao, Yanan; Zhao, Pengcheng; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Zhao, Pengcheng] Nucl Power Inst China, Sci & Technol Reactor Syst Design Technol Lab, Chengdu 610213, Sichuan, Peoples R China.
通讯机构:
[Pengcheng Zhao] S;School of Nuclear Science and Technology, University of South China, Hengyang, Hunan 421001, China<&wdkj&>Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu, Sichuan 610213, China
关键词:
Flow distribution;Lead-bismuth cooled reactor;Multi-objective optimization method;TOPSIS algorithm
摘要:
A reasonable flow distribution can flatten the temperature distribution at the core outlet and reduce the temperature fluctuation, improving the economy and safety of the reactor. Different from a forced circulation reactor, the flow distribution of a natural circulation reactor is automatically adjusted according to the relationship between the fuel assembly power and inlet resistance. In this work, first, a local optimal flow distribution calculation model is constructed based on the closed parallel multi-channel model. Second, a Multi-objective comprehensive evaluation based on the optimal time zone is proposed to find an optimal flow distribution scheme that satisfies multiple requirements during the entire life-cycle. Third, the flow distribution scheme of a small lead-bismuth fast reactor with long life and natural circulation (SPALLER-100) is studied. The Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) algorithm is chosen as the evaluation method with three evaluating indicators for calculation. Ultimately, the subchannel code is selected to verify the flow distribution scheme. The analysis results show that the scheme based on the power distribution of 3182 days performs the best. Compared with the scheme designed by the beginning of life (BOL), the maximum outlet temperature difference reduced by 30 K, the standard deviation of the maximum outlet temperature difference reduced by 41%, and maximum output power increased by 2.35%. The results are in good agreement with the SUBCHANFLOW code, and the maximum relative error is less than 4.5%. © 2022 Elsevier Ltd
语种:
英文
展开
船用堆辐射屏蔽优化设计平台开发与验证
作者:
李玥航;于涛;陈珍平;甘斌;鲜希睿;...
期刊:
核动力工程 ,2022年43(1):208-214 ISSN:0258-0926
通讯作者:
Yu, Tao(yutao29@sina.com)
作者机构:
[李玥航; 于涛; 陈珍平] School of Nuclear Science and Technology, University of South China, Hengyang;421001, China;[甘斌; 鲜希睿; 牛昊轩] Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu;610213, China;Hunan Provincial Digital Reactor Engineering Technology Research Center, Hengyang
通讯机构:
School of Nuclear Science and Technology, University of South China, Hengyang, China
关键词:
船用堆;MOSRT平台;辐射屏蔽;多目标优化
摘要:
船用堆对核反应堆屏蔽设计提出了更高的要求,传统辐射屏蔽设计方法及设计软件已不能满足要求。为了得到更加精确的辐射屏蔽设计,本文基于开源的SALOME框架建立了一套集"几何建模-材料建模-屏蔽优化-结果可视化"功能为一体的船用堆辐射屏蔽多目标优化平台——MOSRT。MOSRT平台可实现屏蔽结构三维CAD实体建模、基于遗传算法的辐射屏蔽多目标优化以及屏蔽计算结果剂量场三维可视化。基于Savannah和MRX船用堆模型对MOSRT平台进行了辐射屏蔽优化验证,优化方案与初始方案相比,在剂量、质量、体积方面均得到了良好的优化效果,证明了MOSRT平台初步具备辐射屏蔽优化设计功能,可为船用堆工程及概念屏蔽设计提供辅助设计手段。
语种:
中文
展开
基于径向基代理模型与小生境遗传算法的铅铋反应堆堆芯智能优化
作者:
李琼;刘紫静;王维嘉;赵鹏程;于涛;...
期刊:
核动力工程 ,2022年43(6):93-100 ISSN:0258-0926
通讯作者:
Liu, Zijing(liuzijing1123@163.com)
作者机构:
[李琼; 刘紫静; 王维嘉; 赵鹏程; 于涛; 常浩彤] School of Nuclear Science and Technology, University of South China, Hunan, Hengyang;421001, China;Hunan Engineering & Technology Research Center for Virtual Nuclear Reactor, University of South China, Hunan, Hengyang;[李琼; 刘紫静; 赵鹏程; 于涛] 421001, China<&wdkj&>Hunan Engineering & Technology Research Center for Virtual Nuclear Reactor, University of South China, Hunan, Hengyang;[李琼; 刘紫静; 王维嘉; 赵鹏程; 于涛; 常浩彤] 421001, China
关键词:
铅铋反应堆;堆芯设计;径向基(RBF)代理模型;小生境遗传算法(NGA);正交拉丁超立方抽样(OLHS);智能优化
摘要:
为解决铅铋反应堆多因素耦合影响下的复杂非线性多维优化问题,构建了基于径向基(RBF)代理模型预测、正交拉丁超立方抽样(OLHS)和小生境遗传算法(NGA)寻优的堆芯智能优化方法,开发了包含抽样、蒙卡程序耦合处理、堆芯参数预测寻优等功能的铅铋反应堆设计优化平台,并以堆芯最小燃料装载量为优化目标进行方案寻优验证。研究结果表明:RBF代理模型可准确快速地预测铅铋反应堆堆芯特性参数,与蒙卡程序计算值比较,其预测的堆芯有效增殖因子(k_(eff))相对误差在±0.1%以内;该智能优化方法应用于铅铋反应堆堆芯优化是可行的,能找到多因素共同变化约束下的最优目标方案,且极大缩减了设计方案的搜索计算时间。本研究建立的堆芯智能优化方法可为铅铋反应堆多物理、多变量、多约束耦合影响的优化设计提供思路。
语种:
中文
展开
Endophytic bacterial strain, Brevibacillus brevis-mediated green synthesis of copper oxide nanoparticles, characterization, antifungal, in vitro cytotoxicity, and larvicidal activity
作者:
Fouda, Amr;Hassan, Saad El-Din;Eid, Ahmed M.;Awad, Mohamed A.;Althumayri, Khalid;...
期刊:
Green Processing and Synthesis ,2022年11(1):931-950 ISSN:2191-9542
通讯作者:
Fouda, Amr(amr_fh83@azhar.edu.eg)
作者机构:
[Fouda, Amr; Eid, Ahmed M.; Hassan, Saad El-Din] Al Azhar Univ, Fac Sci, Dept Bot & Microbiol, Cairo 11884, Egypt.;[Awad, Mohamed A.] Al Azhar Univ, Fac Sci, Dept Zool & Entomol, Cairo 11884, Egypt.;[Althumayri, Khalid] Taibah Univ, Coll Sci, Dept Chem, Al Madinah Al Munawarah 30002, Saudi Arabia.;[Badr, Naglaa Fathi] Al Azhar Univ, Fac Sci Girls Brunch, Dept Zool & Entomol, Cairo 11751, Egypt.;[Hamza, Mohammed F.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构:
[Fouda, A.] D;Department of Botany and Microbiology, Cairo, Egypt
关键词:
breast cancer;Culex antennatus;CuO-NPs;green synthesis;phytopathogenic fungi
摘要:
The biomass filtrate containing various metabolites of endophytic bacterial strain, Brevibacillus brevis PI-5 was used as a biocatalyst for reducing and stabilizing copper oxide nanoparticles (CuO-NPs). UV-Vis spectroscopy, Fourier transform infrared, transmission electron microscopy, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX), X-ray diffraction, and X-ray photoelectron spectroscopy were used for CuO-NPs characterization. A spherical, well-dispersed, and crystallographic structure with sizes of 2-28 nm was formed. The SEM-EDX confirmed the presence of Cu and O with weight percentages of 27.62% and 48.88%, respectively. The biological activities including antifungal, anticancer, and larvicidal of synthesized CuO-NPs were assessed using the fungal radial growth inhibition, MTT assay method, and mortality percentages, respectively. The obtained data showed that the CuO-NPs exhibit high activity in a dose-dependent manner. The growth of three phytopathogenic fungi, Fusarium oxysporum, Alternaria alternata, and Aspergillus niger was decreased by percentages of 64.5% ± 4.1%, 62.9% ± 0.3%, and 70.2% ± 2.3%, respectively at 300 μg·mL-1. Also, various clinical Candida spp. were successfully inhibited with varied zones of inhibition and minimum inhibitory concentration values in ranges of 6.25-50 μg·mL-1. The in vitro cytotoxicity exhibits target-orientation to breast cancer cells (T47D) at low concentration compared to normal cells (HFB4) with IC50 values of 122.3 ± 5.4 and 229.9 ± 5.7 μg·mL-1, respectively. The mortality percentages of I, II, III, and IV instar larvae of Culex antennatus were 60% ± 1.4%, 43.1% ± 1.1%, 36.2% ± 1%, and 32.1% ± 0.9%, at 10 mg·L-1 and increased to 86.9% ± 2.1%, 68.1% ± 1.7%, 64.4% ± 1.9%, and 53.1% ± 1.4% at 50 mg·L-1, respectively. © 2022 Amr Fouda et al., published by De Gruyter.
语种:
英文
展开
Wet-oxygen corrosion resistance and mechanism of bi-layer Mullite/SiC coating for Cf/SiC composites
作者:
Chen, Pengju;Xiao, Peng;Li, Zhuan;Tang, Xian;Liao, Jingjing;...
期刊:
Ceramics International ,2022年48(21):31428-31437 ISSN:0272-8842
通讯作者:
Li, Zhuan(lizhuan@csu.edu.cn);Li, Yang(liyang_csu@126.com)
作者机构:
[Chen, Pengju; Tang, Xian; Liao, Jingjing] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Xiao, Peng; Li, Yang; Li, Zhuan] Cent South Univ, Natl Key Lab Sci & Technol High Strength Struct M, Changsha 410083, Peoples R China.
通讯机构:
[Zhuan Li; Yang Li] N;National Key Laboratory of Science and Technology on High-strength Structural Materials, Central South University, Changsha, 410083, China<&wdkj&>National Key Laboratory of Science and Technology on High-strength Structural Materials, Central South University, Changsha, 410083, China
关键词:
Mullite/SiC;EBCs;Air spray;Water vapour
摘要:
A bi-layer oxidation-resistant coating consisting of a mullite outer coating, and a SiC inner coating on the surface of Cf/SiC composites was prepared by the chemical vapour deposition and an air spray sol-gel process, and its corrosion behavior was evaluated in a wet-oxygen coupling environment. Results show that the formation of SiO2 glass layer and its reaction with mullite particles to form aluminosilicate glass layer, leading to an increase in the density of the mullite outer coating, so that the weight loss of bi-layer Mullite/SiC coating coated C/SiC sample was only 1.11 × 10−3 g·cm−2 in the first 100 h of oxidation. However, the weight loss of the coated sample reached 26.82 × 10−3 g·cm−2 after 200 h of oxidation due to a part of the mullite outer coating was detached. The SiO2 glass phase reacted with water vapour to generate gaseous Si(OH)x, which created distinct holes on the surface of the SiO2 glass layer or inside the molten aluminosilicate glass layer. Eventually, the mullite outer coating was blistered and detached from the surface of the sample due to the combination and growth of holes. © 2022 Elsevier Ltd and Techna Group S.r.l.
语种:
英文
展开
Influence of two simultaneous driven currents on multiple tearing modes in tokamak plasmas
作者:
Zhang, Yemin;Xiang, Dong;Cao, Jinjia;Guo, Kang;Du, Dan;...
期刊:
AIP Advances ,2022年12(11):115016 ISSN:2158-3226
通讯作者:
Xiang, Dong(xiangdong@usc.edu.cn)
作者机构:
[Zhang, Yemin; Xiang, Dong; Guo, Kang; Gong, Xueyu; Cao, Jinjia] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Du, Dan] Univ South China, Sch Math & Phys, Hengyang 421001, Peoples R China.
通讯机构:
[Dong Xiang] S;School of Nuclear Science and Technology, University of South China , Hengyang 421001, People’s Republic of China
摘要:
The influence of two driven currents simultaneously and respectively imposed on the m/n = 2/1 and 3/2 resistive tearing modes in tokamak plasmas is researched by using a three-dimensional toroidal magnetohydrodynamic code CLT. The simulation results show that using two suitable driven currents can better suppress multiple tearing modes than using only one of the two driven currents. When the two suitable driven currents are simultaneously imposed on both the m/n = 2/1 and 3/2 modes, respectively, the two modes may be well suppressed. If only one of the driven currents is imposed on the m/n = 2/1 mode, then the m/n = 2/1 mode may be well suppressed but the m/n = 3/2 mode may be not. Conversely, if only the other of the two driven currents is imposed on the m/n = 3/2 mode, both the two modes may be not suppressed. Moreover, it should be noted that the parameters of using two driven currents to suppress multiple tearing modes must be appropriate; otherwise, some new modes (such as m/n = 5/3 mode) may be excited and grown due to the interaction among the driven currents and multiple modes. © 2022 Author(s).
语种:
英文
展开
An Intelligent Optimization Method for Preliminary Design of Lead-Bismuth Reactor Core Based on Kriging Surrogate Model
作者:
Li, Qiong;Liu, Zijing* ;Xiao, Yingjie;Zhao, Pengcheng;Zhao, Yanan;...
期刊:
Frontiers in Energy Research ,2022年10:849229 ISSN:2296-598X
通讯作者:
Liu, Zijing;Yu, T
作者机构:
[Liu, Zijing; Yang, Tao; Liu, ZJ; Yu, Tao; Zhao, Yanan; Li, Qiong; Xiao, Yingjie; Zhao, Pengcheng] Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;[Liu, Zijing; Yang, Tao; Liu, ZJ; Yu, Tao; Zhao, Yanan; Li, Qiong; Xiao, Yingjie; Zhao, Pengcheng] Univ South China, Hunan Engn & Technol Res Ctr Virtual Nucl Reactor, Hengyang, Peoples R China.
通讯机构:
[Liu, ZJ; Yu, T ] U;Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;Univ South China, Hunan Engn & Technol Res Ctr Virtual Nucl Reactor, Hengyang, Peoples R China.
关键词:
intelligent optimization;Kriging surrogate model;lead-bismuth reactor;orthogonal Latin hypercube sampling;SEUMRE algorithm
摘要:
To meet the numerous application demands of lead-bismuth reactors, different design optimization tasks need to be conducted on these reactors based on the existing reactor core solutions. However, the design optimization of lead-bismuth reactors is a challenging task because it is a complex, multi-dimensional, and nonlinear constrained problem. To resolve these issues and improve the efficiency of design optimization, a new method, called the KSM-OLHS-SEUMRE method, based on the Kriging surrogate model (KSM), orthogonal Latin hypercube sampling (OLHS), and space exploration and unimodal region elimination (SEUMRE) algorithm is proposed in this study. Based on this method, a design optimization program of lead-bismuth reactors (DOPPLER-K) is developed, which realizes functions like sample point generation, optimization analysis, pre-post processing of reactor calculation, coupling of the Reactor Monte Carlo (RMC) calculation code and the Steady-state Thermal-hydraulic Analysis Code (STAC). Further, taking lead-bismuth reactors SPALLER-4 and URANUS as prototypes, the proposed intelligent optimization method for preliminary design of lead-bismuth reactor core is verified. The results show that this method can rapidly and accurately find the target scheme satisfying the optimization conditions, and it is three orders of magnitude faster than pure Monte Carlo calculation. Compared with the initial core scheme of URANUS, the optimization rates of fuel loading, total core mass, active zone volume, and total core volume are reduced by 10.8, 11.5, 18.1, and 17.1%, respectively. These results validate the feasibility and efficacy of the proposed method for design optimization of lead-bismuth reactor core. Copyright © 2022 Li, Liu, Xiao, Zhao, Zhao, Yang and Yu.
语种:
英文
展开
Editorial: Nanotechnology and smart textiles: Sustainable developments of applications
作者:
Fouda, Amr;Hamza, Mohammed F.;Shaheen, Th. I.;Wei, Yuezhou
期刊:
Frontiers in Bioengineering and Biotechnology ,2022年10:1002887 ISSN:2296-4185
通讯作者:
Fouda, Amr(amr_fh83@azhar.edu.eg)
作者机构:
[Fouda, Amr] Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Cairo, Egypt;School of Nuclear Science and Technology, University of South China, Hengyang, China;Nuclear Materials Authority, Cairo, Egypt;[Shaheen, Th. I.] National Research Centre, Textile Research Division, Cairo, Egypt;School of Nuclear Science and Engineering, Shanghai Jiao Tong University, Shanghai, China
通讯机构:
[Fouda, A.] D;Department of Botany and Microbiology, Egypt
关键词:
smart textiles;nanomaterials;UV-protection;antibacterial activity;Green synthesis
摘要:
The huge development in nanotechnology has greatly introduced prospective opportunities to construct improved materials with sophisticated properties to be incorporated into various fields. Such applications are due to the unique properties of nanomaterials originating from the nanoscale structure which are completely different from its bulk materials. One of the current challenges is the possible spread of viral and bacterial infections in the healthcare units, small clinics, doctor's offices, and hospitals that threaten the safety of the healthcare team, visitors, and patients. Textiles and clothes are one of the reasons for spreading infections between patients and others as they are in direct contact with the skin, therefore can be named “second skin”. Therefore, it is urgent to improve the overall properties of textile used for medicinal applications. Nanotechnology can contribute to producing smart textiles with multi-functional properties such as UV protection, flame-retardant, oil, and water repellent, antimicrobial, wrinkle resistance, anti-odor, and antistatic properties. Various chemically and physically-generated metal and metal oxide nanoparticles are applied for smart textiles. However, nanomaterials produced by green approaches are preferred to eliminate or minimize the harmful effects of traditional methods.This issue contains seven articles, two review articles, and five original research papers, covering the current research topic. The first research arti...
语种:
英文
展开
Research on proportional method for experimental facility of lead-based fast reactor with natural circulation
作者:
Zhao, Pengcheng;Wang, Ting;Zhu, Enping;Wang, Tianshi;Wang, Yuxuan
期刊:
Annals of Nuclear Energy ,2022年172 ISSN:0306-4549
通讯作者:
Zhu, Enping(enping_zhu@163.com)
作者机构:
[Wang, Ting; Wang, Tianshi; Zhu, Enping; Wang, Yuxuan; Zhao, Pengcheng] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Hunan, Peoples R China.;[Zhao, Pengcheng] Nucl Power Inst China, Sci & Technol Reactor Syst Design Technol Lab, Chengdu 610213, Sichuan, Peoples R China.
通讯机构:
[Zhu, E.] S;School of Nuclear Science and Technology, University of South China, Hunan, Hengyang, China
关键词:
Lead-based fast reactor;Natural circulation;Proportional method;Similarity criterion
摘要:
Lead-based fast reactors exhibit outstanding natural circulation capabilities, and their natural circulation characteristics are highly valuable for improving the inherent safety of reactor. The existing proportional method forms the theoretical basis for establishing a reasonable and feasible experimental facility that can help study the lead-based fast reactor with natural circulation. In this study, the main similarity groups could be determined by using dimensionless equations of primary cooling systems in typical lead-based fast reactors with natural circulation. Based on the constructed dimensionless similarity groups, the proportional method of a small lead-based fast reactor (Small Natural circulation Lead-based Fast Reactor (SNCLFR-10)) with natural circulation was carried out to obtain the geometric and thermal–hydraulic design parameters of the experimental facility. The proportional method was verified by comparing and analyzing the key thermal and hydraulic parameters of SNCLFR-10 and the experimental facility under rated conditions. The research results show that the key thermal–hydraulic parameter ratios of SNCLFR-10 and the experimental facility are in good agreement with the theoretically deduced ratios, thereby ensuring that the proportional method established here is reasonable and feasible. © 2022 Elsevier Ltd
语种:
英文
展开
Operando Formation of Van der Waals Heterostructures for Achieving Macroscale Superlubricity on Engineering Rough and Worn Surfaces
作者:
Li, Ruiyun;Yang, Xing;Zhao, Jun;Yue, Chengtao;Wang, Yongfu* ;...
期刊:
Advanced Functional Materials ,2022年32(18) ISSN:1616-301X
通讯作者:
Wang, Yongfu;Zhang, Junyan;Meyer, Ernst
作者机构:
[Wang, Yongfu; Zhang, JY; Zhang, Junyan; Li, Ruiyun; Yang, Xing] Chinese Acad Sci, Lanzhou Inst Chem Phys, State Key Lab Solid Lubricat, Lanzhou 70000, Peoples R China.;[Li, Ruiyun; Li, Jiangong] Lanzhou Univ, Inst Mat Sci & Engn, Lanzhou 730000, Peoples R China.;[Shi, Yijun; Zhao, Jun] Lulea Univ Technol, Div Machine Elements, SE-97187 Lulea, Sweden.;[Yue, Chengtao] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Meyer, Ernst] Univ Basel, Dept Phys, Klingelbergstr 82, CH-4056 Basel, Switzerland.
通讯机构:
[Wang, YF; Zhang, JY] C;[Meyer, Ernst; Zhang, Junyan] U;Chinese Acad Sci, Lanzhou Inst Chem Phys, State Key Lab Solid Lubricat, Lanzhou 70000, Peoples R China.;Univ Basel, Dept Phys, Klingelbergstr 82, CH-4056 Basel, Switzerland.;Univ Chinese Acad Sci, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China.
关键词:
graphene;MoS 2;superlubricity;surface roughening;tribochemical reactions;van der Waals heterostructures
摘要:
Macroscale superlubricity breakdown of lubricating materials caused by substrate surface roughening and mechanochemical modification poses great challenges for their practical tribological applications. Here, a facile way is reported to access robust macroscale superlubricity in a vacuum environment, via the operando formation of graphene/transition-metal dichalcogenide (TMDC) heterostructures at wear-induced rough surfaces. By trapping active amorphous carbon (a-C) wear products between TMDC flakes, the sandwich structures readily transform into graphene/TMDC heterostructures during running-in stage, based on shear-induced confinement and load-driven graphitization effects. Then they assemble into multipoint flake-like tribofilms to achieve macroscale superlubricity at steady stage by reducing contact area, eliminating strong cross-interface carbon–carbon interactions and polishing a-C rough nascent surface. Atomistic simulations reveal the preferential formation of graphene/TMDC heterostructures during running-in stage and demonstrate the superlubric sliding of TMDCs on the graphene. The findings are of importance to achieve robust superlubricity and provide a good strategy for the synthesis of other van der Waals heterostructures. © 2022 Wiley-VCH GmbH.
语种:
英文
展开
Ultra-high power laser for vitrification of borosilicate glass
作者:
Yu, Shiwei;Liu, Lie;Han, Lianghua;Sun, Xiangyang;Sun, Jiapo;...
期刊:
Magnetism and Magnetic Materials ,2022年12(9):095211 ISSN:2158-3226
通讯作者:
Liu, Lie(Reseek206@163.com)
作者机构:
[Yu, Shiwei; Liu, Lie; Huang, Haoyue] Univ South China, Sch Elect Engn, Hengyang 421000, Peoples R China.;[Liu, Lie; Zhang, Junze; Han, Lianghua; Wu, Qiupei; Sun, Jiapo; Li, Can] Univ South China, Sch Mech Engn, Hengyang 421000, Peoples R China.;[Liu, Lie; Sun, Xiangyang] Univ South China, Sch Nucl Sci & Technol, Hengyang 421000, Peoples R China.
通讯机构:
[Lie Liu] S;School of Electrical Engineering, University of South China , Hengyang 421000, China
摘要:
The glass solidification technology has been studied by many researchers for decades to handle the trouble of high-level liquid waste (HLLW). However, the widely used joule-heated ceramic melter technology also has disadvantages such as complicated processes, easy deposition of heavy metals, and low thermal efficiency. To deal with these problems, we proposed a new glass solidification device based on ultra-high power laser heating to handle HLLW. HLLW was mixed with borosilicate glass, and melting, clarifying, and annealing processes were carried out in a crucible using laser heat. We test the properties of the borosilicate glass solidified body and then analyze it. The results show that the borosilicate glass beads were completely melted and other indicators are in line with the requirements. As a result, the new device that is heated by an ultra-high laser is feasible for vitrification of HLLW and has the potential to overcome the disadvantages of traditional solidification technology. This research is helpful to explore new glass solidification processes. © 2022 Author(s).
语种:
英文
展开
Effects of biochar/AQDS on As(III)-adsorbed ferrihydrite reduction and arsenic (As) and iron (Fe) transformation: Abiotic and biological conditions
作者:
An, Wenhui;Wu, Chuan;Xue, Shengguo;Liu, Ziyu;Liu, Min;...
期刊:
Chemosphere ,2022年291:133126 ISSN:0045-6535
通讯作者:
Wu, C
作者机构:
[Xue, Shengguo; Wu, Chuan; Wu, C; An, Wenhui; Liu, Ziyu] Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.;[Wu, Chuan; Li, Waichin] Educ Univ Hong Kong, Dept Sci & Environm Studies, Tai Po, Hong Kong, Peoples R China.;[Liu, Min] Univ South China, Coll Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构:
[Wu, C ] C;Cent South Univ, Sch Met & Environm, Changsha 410083, Peoples R China.
关键词:
Biochar;Ferrihydrite;Arsenite;Redox;Vivianite
摘要:
Microbe induced iron (Fe) reduction play an important role in arsenic (As) transformation and the related secondary mineral formation. Meanwhile biochar could react as electron shuttle for this process. Impact of biochar and model electron shuttle anthraquinone-2,6-disulfonate (AQDS) on the chemical/biological iron reduction of As(III)-adsorbed ferrihydrite and the solid-liquid redistribution of As in M1 buffer were studied. Fe reduction results in the release of As adsorbed on ferrihydrite into the solution. Under abiogenic conditions, both biochar and AQDS promoted ferrous production, the chemical oxidation of As(III) and As release. Inoculate with Shewanella oneidensis MR-1, AQDS has greater electronic shuttle function than biochar (with the maximum Fe(II) contents: 154 mg/L > 76.6 mg/L respectively). However, only 12.8 mg/L As was released in the presence of AQDS, which was much lower than that in the presence of biochar (21.6 mg/L), and may be associated with the transformation of As speciation and the formation of secondary minerals. XRD and EDX-SEM confirmed that the As could be fixed by the generated secondary mineral vivianite. The relative contents of vivianite in biological control and AQDS addition were 2.7% and 18.4%, respectively. This study provides information on the transformation and migration of As and Fe with the addition of biochar under anaerobic conditions, which is potential to understand the mechanism of As(III)-contaminated soil remediation. © 2021 Elsevier Ltd
语种:
英文
展开
Functionalization of magnetic chitosan microparticles for high-performance removal of chromate from aqueous solutions and tannery effluent
作者:
Hamza, Mohammed F.;Hamad, Doaa M.;Hamad, Nora A.;Abdel-Rahman, Adel A. -H.;Fouda, Amr;...
期刊:
Chemical Engineering Journal ,2022年428 ISSN:1385-8947
通讯作者:
Wei, Yuezhou;Guibal, Eric
作者机构:
[Wei, Yuezhou; Hamza, Mohammed F.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Wei, Yuezhou; Hamza, Mohammed F.] Guangxi Univ, Sch Resources Environm & Mat, Nanning 530004, Peoples R China.;[Hamza, Mohammed F.] Nucl Mat Author, POB 530,El Maadi, Cairo, Egypt.;[Hamad, Doaa M.; Abdel-Rahman, Adel A. -H.; Hamad, Nora A.] Menoufia Univ, Fac Sci, Shebine El Koam, Egypt.;[Fouda, Amr] Al Azhar Univ, Fac Sci, Bot & Microbiol Dept, Nasr City, Cairo 11884, Egypt.
通讯机构:
[Wei, Yuezhou] U;[Wei, Yuezhou] G;[Guibal, Eric] I;Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;Guangxi Univ, Sch Resources Environm & Mat, Nanning 530004, Peoples R China.
关键词:
Antimicrobial activity of functionalized materials;Application to tannery wastewater;Characterization of sorption mechanisms by FTIR and XPS analyses;Functionalization of magnetic chitosan nanoparticles for improving chromate removal;Metal desorption and sorbent recycling;Sorption isotherms and uptake kinetics
摘要:
Textile and tannery industries are highly contaminating with discharge of high Cr concentrations. Developing bio-based sorbents with strong affinity for chromate, fast kinetics, and high recyclability is strategic for better reuse of industrial wastewater. Magnetic chitosan micro-particles (MC, for enhancing mass transfer) may constitute a solution for chromate removal from acidic solutions. The functionalization of this support with aminothiazole groups (ATA@MC) or imidazole carboxamide (AIC@MC) significantly improves chromate removal, with sorption capacities close to 6 mmol Cr g−1, at pH 2. The Langmuir and the Sips equations finely fit sorption isotherms, while the pseudo-first order rate equation fits well uptake kinetics (equilibrium within 60 min). Sorption and desorption properties are remarkably stable: sorption efficiency decreases by less than 6% at the fifth cycle (while the desorption efficiency maintains above 99%). The sorbents are highly selective for chromate removal from acidic tannery wastewater (against base metals). FTIR and XPS analyses are used for characterizing the materials and for identifying the binding mechanisms (including chromate reduction into Cr(III)). The sorbents are both showing promising performances for Cr(VI) removal in acidic solutions, including in very complex solutions such as tannery wastewater. AIC@MC is more selective for Cr(VI) removal, while ATA@MC has a broader reactivity for a wider family of metal ions. The antimicrobial properties of the functionalized sorbents are characterized by the determination of the zone of inhibition (ZOI) against Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli and Candida albicans: the inhibition is slightly improved compared with magnetite chitosan microparticles. More generally, the Gram- bacteria are slightly more sensitive to the functionalized sorbents than Gram+ bacteria and Candida fungus. © 2021
语种:
英文
展开
自然循环条件下倒U型管蒸汽发生器一次侧倒流现象关键影响因素研究
作者:
王天石;王宇轩;赵鹏程;王曦婕;凌煜凡;...
期刊:
核动力工程 ,2022年43(2):40-46 ISSN:0258-0926
通讯作者:
Zhao, Pengcheng(zhaopengcheng1030@163.com)
作者机构:
[王天石; 王宇轩; 赵鹏程; 王曦婕; 凌煜凡; 王雨晴; 朱恩平] School of Nuclear Science and Technology, University of South China, Hengyang;421001, China;Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu;610213, China;[王天石; 王宇轩; 王曦婕; 凌煜凡; 王雨晴; 朱恩平] 421001, China
通讯机构:
School of Nuclear Science and Technology, University of South China, Hengyang, China
关键词:
自然循环;倒U型管蒸汽发生器(UTSG);倒流;计算流体力学;关键影响因素
摘要:
倒U型管蒸汽发生器(UTSG)在自然循环条件下存在倒流现象,影响一回路冷却剂系统载热能力及自然循环能力。本文参照芬兰压水堆热工实验装置(PWR PACTEL)中UTSG设计参数,利用计算流体力学(CFD)软件Fluent模拟流量匀速下降工况下UTSG中的倒流现象,研究一次侧运行参数、UTSG设计参数以及二次侧运行参数对于倒流现象的影响。结果表明,提高UTSG一次侧温度、一次侧运行压力、倒U型管热导率将增大UTSG的临界质量流量,使得UTSG更易发生倒流;提高UTSG二次侧给水量、二次侧温度以及倒U型管内壁粗糙度将使得UTSG临界质量流量下降,抑制倒流现象的发生;而改变倒U型管壁厚对倒流现象几乎不造成影响;相较于改变二回路温度而言,改变一回路温度对于倒流现象的影响更为显著。本研究结果可为UTSG的参数优化提供一定参考。
语种:
中文
展开
基于流量功率比恒定的小型铅基快堆运行研究
作者:
胡杨;刘依诺;曾文杰;梁乐华;李楚豪
期刊:
核动力工程 ,2022年43(4):131-135 ISSN:0258-0926
通讯作者:
Zeng, Wenjie(zengwenjie0218@163.com)
作者机构:
[胡杨; 刘依诺; Zeng, Wenjie; 梁乐华; 李楚豪] School of Nuclear Science and Technology, University of South China, Hunan, Hengyang;421001, China;[胡杨; 刘依诺; Zeng, Wenjie; 梁乐华; 李楚豪] 421001, China
关键词:
小型铅基快堆;流量功率比;运行策略
摘要:
为开展小型铅基快堆运行策略研究,建立堆芯传递函数模型,利用比例-积分-微分(PID)控制器,结合控制棒驱动机构,分别设计堆芯流量功率比恒定与堆芯稳定核功率的运行方案。分别建立不同运行策略下的控制系统,开展一回路流量阶跃和堆芯反应性扰动仿真。结果表明,在引入一回路流量阶跃下降工况下,稳定核功率运行方案由于堆芯功率恒定而导致堆芯出口温度过高;在流量功率比恒定方案下,堆芯功率跟随一回路流量下降从而保证堆芯出口温度迅速稳定在安全范围内;在阶跃反应性扰动下,2种方案均可迅速调控堆芯功率的上冲幅度和超调量,堆芯出口温度基本维持恒定。
语种:
中文
展开