摘要：
We study the reheating predictions in the non-minimally coupled inflationary model of the quartic inflationary potential, both without and with the self-induced radiative corrections of the inflaton taken into account. We compare these predictions between two different formalisms of gravity: metric and Palatini, and between two different prescriptions of the radiative corrections. We find that the radiative corrections have a non-negligible influence on reheating predictions although two different prescriptions almost give the same results. Different formalisms of gravity lead to different reheating predictions, and the difference becomes more apparent when the radiative corrections are considered.(c) 2023 Elsevier B.V. All rights reserved.
通讯机构：
[Min Liu; Yanfang Xia] C;College of Nuclear Science and Technology, University of South China, Hengyang 421200, Hunan, PR China<&wdkj&>College of Nuclear Science and Technology, University of South China, Hengyang 421200, Hunan, PR China<&wdkj&>Zhuhai Tsinghua University Research Institute Innovation Center, 101 University Ave, Tangjiawan Zhuhai 519000, PR China
关键词：
NdFe0;5Cr0;Spin reorientations;Magnetic disorders;Anti-site defects;Molecular field theories;Mo?ssbauer
摘要：
Sophisticated spin instruments require high-precision spin control. In this study, we accurately study the intrinsic magnetic properties of the strongly disordered system NdFe0.5Cr0.5O3 through molecular field models combined with anti-site defects (ASD) theory. The three constituent sub-magnetic phases of the system are separated, and their magnetization contributions are calculated separately. Fitting the angle of the A/B magnetic moment at a given temperature, the reorientation temperature point and temperature dependence of different magnetic phases are obtained. This research will provide a very good theoretical support for studying complex disordered systems and applying high-precision spin control and lay a foundation for the design of new functional materials.
期刊：
Journal of Water Process Engineering,2023年53:103582 ISSN：2214-7144
通讯作者：
Xu Zhang
作者机构：
[Wan, Qiyue; Yue, Chengtao; Zhang, Xu; Wang, Hai; Liu, Renjuan; Liu, Longcheng] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Yue, Chengtao; Zhang, Xu; Liu, Longcheng] Univ South China, R&D & Modelling Ctr Treatment & Disposal Radioact, Hengyang 421001, Peoples R China.;[Liu, Longcheng] Beijing Res Inst Chem Engn & Met, Beijing 101149, Peoples R China.
通讯机构：
[Xu Zhang] S;School of Nuclear Science and Technology, University of South China, Hengyang 421001, China<&wdkj&>R&D and Modelling Center for Treatment and Disposal of Radioactive Waste, University of South China, Hengyang 421001, China
摘要：
The uranium extraction from radioactive wastewater is vitally important for both the sustainable nuclear energy and environmental protection. However, the efficient extraction of uranium (VI) faces great challenges due to the complex compositions of radioactive wastewater. In this work, phosphate-based hypercrosslinked polymer (HCP) is designed and synthesized via the Friedel-Crafts polymerization of different aryl phosphate with crosslinking monomer for efficient uranium (VI) extraction. The HCP has uranophilic phosphate group, large specific surface area and mesoporous structure. It can effectively adsorb uranium (VI) from solution under various pH conditions and the adsorption efficiency can achieve 98 %. The maximum sorption capacity of HCP reaches 302 mg/g at pH 7.0 with a sorbent dosage of 0.33 g/L, which is higher than many other phosphate-based polymer. Meantime, it shows good sorption selectivity for uranium (VI) over many other coexisting metal ions. It shows recyclability and can be well applied to the fixed-bed sorption column for long-time uranium (VI) extraction. Investigations on sorption mechanism reveals that the coordination effect between phosphate groups and uranium (VI) ions en-hances the effective sorption of uranium (VI) on HCP. This work provides a facile way to construct heterogeneous phosphate sorbents, and demonstrates their potential for practical application in uranium (VI) recovery from radioactive wastewater.
作者机构：
School of Nuclear Science and Technology, University of South China, Hengyang, Hunan Province 421001, People's Republic of China;[Xie, R.; Hu, T.; Tan, Y.] College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, Hunan Province 421008, People's Republic of China;Hunan Provincial Key Laboratory of Radon, Hengyang, Hunan Province 421001, People's Republic of China;[Fan, Z.] School of Nuclear Science and Technology, University of South China, Hengyang, Hunan Province 421001, People's Republic of China<&wdkj&>College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, Hunan Province 421008, People's Republic of China<&wdkj&>Hunan Provincial Key Laboratory of Radon, Hengyang, Hunan Province 421001, People's Republic of China;[Cai, X.; Luo, Y.; Qin, F.; Qiu, S.; Shan, J.] School of Nuclear Science and Technology, University of South China, Hengyang, Hunan Province 421001, People's Republic of China<&wdkj&>Hunan Provincial Key Laboratory of Radon, Hengyang, Hunan Province 421001, People's Republic of China
通讯机构：
[Y Tan] C;[J Shan] S;School of Nuclear Science and Technology, University of South China, Hengyang, Hunan Province 421001, People's Republic of China<&wdkj&>Hunan Provincial Key Laboratory of Radon, Hengyang, Hunan Province 421001, People's Republic of China<&wdkj&>College of Physics and Electronic Engineering, Hengyang Normal University, Hengyang, Hunan Province 421008, People's Republic of China
摘要：
Accurately measuring Rn-220 is crucial for evaluating natural radiation exposure. For the large volume of normal scintillation cell, the detection efficiencies for different energy of α particles decayed from Rn-222, Rn-220 and their progeny are varied. To address this, two systems of the low-pressure scintillation cell were designed to make the shortest range of α particles with minimum energy decayed from Rn-222 longer than the longest distance between any two points in the scintillation cell by reducing air pressure. Thus, the detection efficiencies of the low-pressure scintillation cell for α particles decayed from Rn-222, Rn-220 and their progeny are same. The detection efficiency of low-pressure scintillation cell for α particles can be obtained by the standard radon chamber, and then the calibration factor of Rn-220 can be determined by low-pressure scintillation. Several verification experiments were performed. The experimental results show that the detection efficiencies of Rn-222 and Rn-220 at the air pressure of 0.4 P are very close and become saturated for lower values of air pressure. The calibration factor of Rn-220 calculated using the detection efficiency (0.76 ± 0.04) at the air pressure of 0.4 P is 53.75 Bq m−3 min−1 ± 2.96 Bq m−3 min−1 (k = 1).
摘要：
Irradiation damage is one of the main drawbacks restricting the application of Silicon Photomultiplier (SiPM), especially in high irradiance environments such as space, colliders, and nuclear power plants. In-situ current annealing is a method of using the self-current heating of SiPM, and because it does not require disassembly of the SiPM and additional heating devices, it exhibits potential for dealing with radiation damage. We investigate the in-situ annealing performance of three types of SiPM for irradiation damage. The annealing current and time are optimized and the SiPM performance before and after annealing is compared. It was found that after annealing the dark currents of the three types of SiPMs decreased significantly by 1–2 orders of magnitude. Finally, the variation of SiPM performance with temperature is investigated. The energy resolution does not recover as well as the dark current.
作者：
Fouda, Amr;Saied, Ebrahim;Eid, Ahmed M.;Kouadri, Fayza;Alemam, Ahmed M.;...
期刊：
Journal of Functional Biomaterials,2023年14(4):205- ISSN：2079-4983
通讯作者：
Saad El-Din Hassan<&wdkj&>Amr Fouda
作者机构：
[Fouda, Amr; Eid, Ahmed M.; Hassan, Saad El-Din; Saied, Ebrahim; Alemam, Ahmed M.] Al Azhar Univ, Fac Sci, Dept Bot & Microbiol, Cairo 11884, Egypt.;[Kouadri, Fayza] Middle East Univ, Fac Pharm, Amman 11831, Jordan.;[Hamza, Mohammed F.] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Hamza, Mohammed F.] Nucl Mat Author, POB 530, Cairo 11728, Egypt.;[Alharbi, Maha] Princess Nourah Bint Abdulrahman Univ, Coll Sci, Dept Biol, POB 84428, Riyadh 11671, Saudi Arabia.
通讯机构：
[Saad El-Din Hassan; Amr Fouda] A;Authors to whom correspondence should be addressed.<&wdkj&>Department of Botany and Microbiology, Faculty of Science, Al-Azhar University, Nasr City, Cairo 11884, Egypt
摘要：
The peel aqueous extract of Punica granatum was utilized to fabricate zinc oxide nanoparticles (ZnO-NPs) as a green approach. The synthesized NPs were characterized by UV-Vis spectroscopy, Fourier transform infrared (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy, which was attached to an energy dispersive X-ray (SEM-EDX). Spherical, well arranged, and crystallographic structures of ZnO-NPs were formed with sizes of 10-45 nm. The biological activities of ZnO-NPs, including antimicrobial and catalytic activity for methylene blue dye, were assessed. Data analysis showed that the antimicrobial activity against pathogenic Gram-positive and Gram-negative bacteria, as well as unicellular fungi, was observed to occur in a dose-dependent manner, displaying varied inhibition zones and low minimum inhibitory concentration (MIC) values in the ranges of 6.25-12.5 mu g mL(-1). The degradation efficacy of methylene blue (MB) using ZnO-NPs is dependent on nano-catalyst concentration, contact time, and incubation condition (UV-light emission). The maximum MB degradation percentages of 93.4 +/- 0.2% was attained at 20 mu g mL(-1) after 210 min in presence of UV-light. Data analysis showed that there is no significant difference between the degradation percentages after 210, 1440, and 1800 min. Moreover, the nano-catalyst showed high stability and efficacy to degrade MB for five cycles with decreasing values of 4%. Overall, P. granatum-based ZnO-NPs are promising tools to inhibit the growth of pathogenic microbes and degradation of MB in the presence of UV-light emission.
作者机构：
[Deng, Nianbiao] Univ South China, Sch Resource Environm & Safety Engn, Hengyang 421001, Peoples R China.;[Xie, Chao; Xie, Jinsen; Yu, Tao] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Hou, Cheng] China Inst Atom Energy, Beijing 102413, Peoples R China.;[Li, Zhulun] North China Elect Power Univ, Sch Nucl Sci & Engn, Beijing 102206, Peoples R China.
通讯机构：
[Jinsen Xie; Tao Yu] A;Authors to whom correspondence should be addressed.<&wdkj&>School of Nuclear Science and Technology, University of South China, Hengyang 421001, China
关键词：
ADS Subcritical Reactor;deep subcriticality;heterogeneity of neutron fluence rate in time–space;Monte Carlo homogenization method;neutron kinetics
通讯机构：
[Yanfang Xia; Min Liu; Yanfang Xia Yanfang Xia Yanfang Xia; Min Liu Min Liu Min Liu] C;College of Nuclear science and Technology, University of South China, Hengyang, 421001 China<&wdkj&>College of Nuclear science and Technology, University of South China, Hengyang, 421001 China<&wdkj&>Zhuhai Tsinghua University Research Institute Innovation Center, 101 University Ave, Tangjiawan, Zhuhai, 519000 China
摘要：
Herein, the effects of different Sr content doping on the crystal structure and electronic structure of La1−xSrxFeO3−δ (x = 0, 0.2, 0.5, 0.8, 1.0) are studied by X‐ray diffraction (XRD) and Mössbauer spectroscopy. The study provides some reference for future research to study the effect of iron‐oxidation state on the specific activity of strontium‐doped LaFeO3. Herein, the effects of different Sr content doping on the crystal structure and electronic structure of La1−xSrxFeO3−δ (LSFO‐x, x = 0, 0.2, 0.5, 0.8, 1.0) are studied by X‐ray diffraction (XRD) and Mössbauer spectroscopy. It is shown in the XRD results that the structure of LSFO‐x changes from orthorhombic (Pnma [#62]) to cubic (Pm‐3m (#221)) to tetragonal (I4/mmm (#139)) with increasing strontium doping. It is shown in Mössbauer spectrum analysis that with the gradual increase of Sr doping, iron ions finally change from +3 oxidation state to +4 oxidation state after passing through an intermediate oxidation state of +3.5. The Fe3.5+ state can result from rapid electron exchange (Fe3+ + Fe4+ ⇋ Fe4+ + Fe3+) between iron ions of different oxidation states within the crystal structure; the study provides some reference for future research to study the effect of iron‐oxidation state on the specific activity of strontium‐doped LaFeO3.
摘要：
A process for treating low radioactive uranium wastewater by ultrasonic combined flocculation and precipitation has been developed and optimized. By using arsenazo III spectrophotometry to detect the mass concentration of uranium ions, the optimal coupling mode of ultrasonic flocculation and the optimal values of pH value, flocculant dosage, and ultrasonic power were obtained through single factor experiments. The conclusion drawn is that the optimal coupling method is to first add flocculants, then treat the solution with ultrasound, and finally stir the solution. The optimal values for each single factor are: the initial pH value of the solution is 9, the dosage of flocculant is 80 mg/L, and the sound energy density is 0.36 W/ml.The Box Behnken response surface experiment was designed using Design-Expert software. After completing the response surface experiment, a regression model for uranium ion removal rate was obtained. The highest uranium ion removal rate under theoretical conditions was obtained by solving the model.The predicted values of uranium ions removal rate of 95.68% was obtained with an acoustic energy density of 0.436 W/ml and a flocculant dosage of 88 mg/L at pH 9.It was observed that the actual experimental data under the same conditions are 95.41% The order of the influence factors of each process parameter on the uranium ion removal rate is: pH > flocculant dosage > ultrasonic power. Among them, there was a significant interaction between ultrasonic power and flocculant dosage.
摘要：
After an emergency shutdown of a lead-bismuth fast reactor, thermal stratification occurs in the upper Plenum, which negatively impacts the integrity of the reactor structure and the residual heat removal capacity of natural circulation flow. The research on thermal stratification of reactors has mainly been conducted using an experimental method, a system program, and computational fluid dynamics (CFD). However, the equipment required for the experimental method is expensive, accuracy of the system program is unpredictable, and resources and time required for the CFD approach are extensive. To overcome the defects of thermal stratification analysis, a high-precision full-order thermal stratification model based on CFD technology is prepared in this study. Furthermore, a reduced-order model has been developed by combining proper orthogonal decomposition (POD) with Galerkin projection. A comparative analysis of thermal stratification with the proposed full-order model reveals that the reduced-order thermal stratification model can well simulate the temperature distribution in the upper plenum and rapidly elucidate the thermal stratification interface characteristics during the lead-bismuth fast reactor accident. Overall, this study provides an analytical tool for determining the thermal stratification mechanism and reducing thermal stratification.
作者机构：
[Pengju Chen; Xian Tang] School of Nuclear Science and Technology, University of South China, Hengyang 421001, China;[Peng Xiao; Zhuan Li] State Key Laboratory of Powder Metallurgy, Central South University, Changsha 410083, China;[Yang Li] National Key Laboratory of Science and Technology on High-strength Structural Materials, Central South University, Changsha 410083, China;[Yichen Wang] School of Engineering and Materials Science, Queen Mary University of London, London E1 4NS, UK
通讯机构：
[Zhuan Li] S;[Yang Li] N;State Key Laboratory of Powder Metallurgy, 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
摘要：
To improve the corrosion resistance of Cf/SiC composites in a water vapor oxygen coupled environment, the bi-layer Yb2Si2O7/SiC and tri-layer Yb2Si2O7/(SiCw-Mullite, SM)/SiC environment barrier coatings were designed and prepared on the surface of Cf/SiC composites by chemical vapor deposition and sol-gel method united with air spraying. Results show that the mass loss of bi-layer Yb2Si2O7/SiC coating coated samples was 17.24 × 10−3 g cm−2 after 200 h oxidation at 1673 K, and the average compression strength retention rate was only 79.44% due to the formation of wide penetrating cracks. Comparatively, SiC whiskers in SM middle coating can not only increase the crack propagation resistance of mullite middle coating, but also alleviate the difference of coefficient of thermal expansion between Yb2Si2O7 outer coating and mullite middle coating. Therefore, the mass loss of tri-layer Yb2Si2O7/SM/SiC coating coated samples was only 2.93 × 10−3 g cm−2 after 200 h oxidation at 1673 K, and the average compression strength retention rate was up to 98.79%.
摘要：
First‐principles calculations show that black phosphorene (BP) exhibits strong adsorption with uranium and thorium atoms even when the temperature reaches 500 and 673 K. The strong adsorption is stabilized by the p‐d coupling between the phosphorus and actinide atoms. BP is an ideal adsorption and separation material for actinides with promising potential applications such as uranium extraction from seawater. Abstract Density functional theory (DFT) calculations were carried out in this work to systematically investigate the adsorption properties of monolayer black phosphorene (BP) for actinide uranium (U), thorium (Th), and plutonium (Pu) atoms. More specifically, the linear response method was used and the Hubbard U values of 2.97 and 2.61 eV were fitted describing the strong lattice point Coulomb interactions of the U and Pu 5f orbitals, respectively. From the DFT + U calculations, it was demonstrated that the U, Th, and Pu atoms can be favorably adsorbed on the hollow sites of the BP surface, with an adsorption energy of 3.48, 4.93, and 0.98 eV, respectively. By analyzing the electronic structure, charge transfer, and highest occupied molecular orbital, it was revealed that the U and Th adatoms can induce the generation of impurity states within the band gap of BP and stabilize their adsorption by strong p‐d coupling with the phosphorus atoms. In addition, from the electron–phonon coupling calculations, it was revealed that the temperature for the stable adsorption of the U and Th adatoms can reach as high as 500 and 673 K. By using the adsorption rate equation, the critical temperature for the adsorption–desorption transition of U and Pu adatoms was estimated to be 632 and 185 K, respectively, while the Th adatom did not tend to desorb. Our results clearly indicate that BP is an ideal adsorption and separation material for actinides with promising potential applications, such as uranium extraction from seawater.
作者机构：
[于涛; 赵鹏程; 赵亚楠; 杨涛] School of Nuclear Science and Technology, University of South China, Hunan, Hengyang;421001, China;Hunan Engineering and Technology Research Center for Virtual Nuclear Reactor, University of South China, Hunan, Hengyang;[于涛; 赵鹏程; 赵亚楠; 杨涛] 421001, China<&wdkj&>Hunan Engineering and Technology Research Center for Virtual Nuclear Reactor, University of South China, Hunan, Hengyang;[于涛; 赵鹏程; 赵亚楠; 杨涛] 421001, China
作者机构：
[余清远; 赵鹏程] School of Nuclear Science and Technology, University of South China, Hunan, Hengyang;421001, China;[马誉高; 张英楠] Science and Technology on Reactor System Design Technology Laboratory, Nuclear Power Institute of China, Chengdu;610213, China;Department of Engineering Physics, Tsinghua University, Beijing
期刊：
International Journal of Applied Ceramic Technology,2023年20(3):1740-1752 ISSN：1546-542X
通讯作者：
Chen, P.;Li, Y.
作者机构：
[He, Ling; Xiao, Peng; Pan, Ling; Li, Yang] Cent South Univ, State Key Lab Powder Met, Changsha, Peoples R China.;[Chen, Pengju] Univ South China, Sch Nucl Sci & Technol, Hengyang, Peoples R China.;[Zhou, Wei] Hunan Univ Technol, Coll Met & Mat Engn, Zhuzhou, Peoples R China.;[Chen, Pengju; Li, Yang] Cent South Univ, Powder Met Res Inst, 932 Yuelu Ave,Lushan South Rd, Changsha 410083, Peoples R China.
通讯机构：
[Li, Y.] S;[Chen, P.] P;Powder Metallurgy Research Institute, No.932 Yuelu Avenue, Lushan South road, China;State Key Laboratory of Powder Metallurgy, China
摘要：
The mullite and ytterbium disilicate (beta-Yb2Si2O7) powders as starting materials for the Yb2Si2O7/mullite/SiC tri-layer coating are synthesized by a sol-gel method. The effect of SiC whiskers on the anti-oxidation properties of Yb2Si2O7/mullite/SiC tri-layer coating for C/SiC composites in the air environment is deeply studied. Results show that the formation temperature and complete transition temperature of mullite were 800-1000 and 1300 & DEG;C, respectively. Yb2SiO5, alpha-Yb2Si2O7, and beta-Yb2Si2O7 were gradually formed between 800 and 1000?, and Yb2SiO5 and alpha-Yb2Si2O7 were completely transformed into beta-Yb2Si2O7 at a temperature above 1200 & DEG;C. The weight loss of Yb2Si2O7/(SiCw-mullite)/SiC tri-layer coating coated specimens was 0.15 x 10(-3) g cm(-2) after 200 h oxidation at 1400?, which is lower than that of Yb2Si2O7/mullite/SiC tri-layer coating (2.84 x 10(-3) g cm(-2)). The SiC whiskers in mullite middle coating can not only alleviate the coefficient of thermal expansion difference between mullite middle coating and beta-Yb2Si2O7 outer coating, but also improve the self-healing performance of the mullite middle coating owing to the self-healing aluminosilicate glass phase formed by the reaction between SiO2 (oxidation of SiC whiskers) and mullite particles.
期刊：
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY,2023年145(22):12206-12213 ISSN：0002-7863
通讯作者：
Zhang, FX
作者机构：
[Li, Jiangnan; Fan, Wenjun; Zhang, Fuxiang; Mehmood, Rashid; Zhang, Yashi] Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis iChEM, Dalian Natl Lab Clean Energy, Dalian 116023, Liaoning, Peoples R China.;[Li, Jiangnan; Mehmood, Rashid; Zhang, Yashi] Univ Chinese Acad Sci, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China.;[Zhou, Zhen; Hu, Xu] Nankai Univ, Inst New Energy Mat Chem, Renewable Energy Convers & Storage Ctr ReCast, Sch Mat Sci & Engn,Minist Educ, Tianjin 300350, Peoples R China.;[Liu, Peijia; Wang, Junhu] Chinese Acad Sci, Dalian Inst Chem Phys, Ctr Adv Mossbauer Spect, Moossbauer Effect Data Ctr, Dalian 116023, Liaoning, Peoples R China.;[Liu, Min] Univ South China, Coll Nucl Sci & Technol, Hengyang 421001, Peoples R China.
通讯机构：
[Zhang, FX ] C;Chinese Acad Sci, Dalian Inst Chem Phys, State Key Lab Catalysis iChEM, Dalian Natl Lab Clean Energy, Dalian 116023, Liaoning, Peoples R China.
摘要：
Iron (Fe)-based bimetallic oxides/hydroxides have been widely investigated for promising alkaline electrochemical oxygen evolution reactions (OERs), but it still remains argumentative whether Fe(3+) or Fe(4+) intermediates are highly active for efficient OER. Here, we rationally designed and prepared one Fe, V-based bimetallic composite nanosheet by employing the OER-inert V element as a promoter to completely avoid the argument of real active metals and using our recently developed one-dimensional conductive nickel phosphide (NP) as a support. The as-obtained hierarchical nanocomposite (denoted as FeVO(x)/NP) was evaluated as a model catalyst to gain insight into the iron-based species as highly active OER sites by performing in situ X-ray absorption spectroscopy and (57)Fe Mössbauer spectroscopy measurements. It was found that the high-valent Fe(4+) species can only be detected during the OER process of the FeVO(x)/NP nanocomposite instead of the iron counterpart itself. Together with the fact that the OER activities of both the vanadium and iron counterparts are by far worse than that of the FeVO(x)/NP composite, we can confirm that the high-valent Fe(4+) formed are the highly active species for efficient OER. As demonstrated by density functional theory simulations, the composite of Fe and V metals is proposed to cause a decreased Gibbs free energy as well as theoretical overpotential of water oxidation with respect to its counterparts, as is responsible for its excellent OER performance with extremely low OER overpotential (290 mV at 500 mA cm(-2)) and extraordinary stability (1000 h at 100 mA cm(-2)).
