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.
作者机构：
[黄仕元; 林森焕; 董雯; 王国华; 吴兴良; 袁瀚钦] School of Civil Engineering, University of South China, Hengyang;421001, China;[黄仕元; 林森焕; 董雯; 王国华; 吴兴良; 袁瀚钦] 421001, China
通讯机构：
[Huang, S.] S;School of Civil Engineering, China
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.
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.
期刊：
Science and Technology of Nuclear Installations,2023年2023 ISSN：1687-6075
通讯作者：
Yang, XH
作者机构：
[Jiang, Panpan] Univ South China, Sch Nucl Sci & Technol, Hengyang 421001, Peoples R China.;[Jiang, Panpan] Univ South China, Sch Civil Engn, Hengyang 421001, Peoples R China.;[Yang, XH; Yang, Xiaohua; Liu, Zhenghai; Zeng, Tiejun; Wang, Chaofeng; Wan, Yaping; Jiang, Panpan; Mao, Yu; Nie, Mingxing] Intelligent Nucl Secur Technol Lab, Hengyang 421001, Peoples R China.;[Yang, XH; Yang, Xiaohua; Liu, Zhenghai; Wang, Chaofeng; Wan, Yaping; Mao, Yu; Nie, Mingxing] Univ South China, Sch Comp, Hengyang 421001, Peoples R China.
通讯机构：
[Yang, XH ] I;Intelligent Nucl Secur Technol Lab, Hengyang 421001, Peoples R China.;Univ South China, Sch Comp, Hengyang 421001, Peoples R China.
关键词：
Introduction;Materials and Methods;Results;Discussion;Conclusion;Abstract;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interests;Authors’ Contributions;Funding Statement;Acknowledgements;Acknowledgments;Supplementary Materials;Reference;Dataset Description;Dataset Files;Abstract;Introduction;Introduction and Materials;Introduction and Methods;Materials;Materials and Methods;Methods;Results;Discussion;Results and Discussion;Discussion and Conclusion;Results and Conclusion;Conclusion;Conclusions;Data Availability;Additional Points;Ethical Approval;Consent;Disclosure;Conflicts of Interest;Authors’ Contributions;Funding Statement;Acknowledgements;Supplementary Materials;References;Appendix;Abbreviations;Preliminaries;Introduction and Preliminaries;Notation;Proof of Theorem;Proofs;Analysis of Results;Examples;Numerical Example;Applications;Numerical Simulation;Model;Model Formulation;Systematic Palaeontology;Nomenclatural Acts;Taxonomic Implications;Experimental;Synthesis;Overview;Characterization;Background;Experimental;Theories;Calculations;Model Verification;Model Implementation;Geographic location;Study Area;Geological setting;Data Collection;Field Testing;Data and Sampling;Dataset;Literature Review;Related Works;Related Work;System Model;Methods and Data;Experimental Results;Results and Analysis;Evaluation;Implementation;Case Presentation;Case Report;Search Terms;Case Description;Case Series;Background;Limitations;Additional Points;Case;Case 1;Case 2 etc.;Concern Details;Retraction Details;Copyright;Related Articles
摘要：
The rapid expansion of nuclear technology across various sectors due to global economic growth has led to a substantial rise in the transportation of radioactive materials. The International Atomic Energy Agency (IAEA) estimates that approximately 20 million shipments of radioactive materials occur annually. In this context, ensuring the safety and security of radioactive material transportation is of significant importance. IAEA’s “Security of Radioactive Materials in Transport” (Nuclear Security Series No. 9-G) mandates that an effective transport security system should provide immediate detection of any unauthorized removal of the packages. In the present study, an innovative Adam-optimized BP neural network model is developed for detecting unauthorized movements of radioactive material packages. To analyze the performance of the proposed algorithm, numerous experiments were conducted. The results demonstrate that the proposed method achieves a 99.17% accuracy rate in detecting unauthorized movements of radioactive materials, with a missed alarm rate of 0.72% and a false alarm rate of 0.1%. This method also enables real-time detection of unauthorized removal of radioactive materials and effectively enhances the security of radioactive materials during transport to reduce the risks of theft, loss, diversion, or sabotage.
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%.
