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Numerical simulations for radon migration and exhalation behavior during measuring radon exhalation rate with closed-loop method

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Nuclear Science and Techniques 2024年第1期35卷 81-95页

作者： Ming Xia yong-jun ye Shu-Yuan Liu School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001China

Accurate measurements of the radon exhalation rate help identify and evaluate radon risk regions in the *** these measurement methods,the closed-loop method is frequently ***,traditional experiments are insufficient or cannot analyze the radon migration and exhalation patterns at the gas–solid interface in the accumulation *** CFD-based technique was applied to predict the radon concentration distribution in a limited space,allowing radon accumulation and exhalation inside the chamber intuitively and *** this study,three radon exhalation rates were defined,and two structural ventilation tubes were designed for the *** consistency of the simulated results with the variation in the radon exhalation rate in a previous experiment or analytical solution was *** effects of the vent tube structure and flow rate on the radon uniformity in the chamber;permeability,insertion depth,and flow rate on the radon exhalation rate and the effective diffusion coefficient on back-diffusion were *** on the results,increasing the inser-tion depth from 1 to 5 cm decreased the effective decay constant by 19.55%,whereas the curve-fitted radon exhalation rate decreased(lower than the initial value)as the deviation from the initial value increased by approximately 7%.Increasing the effective diffusion coefficient from 2.77×10^(-7) to 7.77×10^(-6) m^(2) s^(-1) made the deviation expand from 2.14 to 15.96%.The conclusion is that an increased insertion depth helps reduce leakage in the chamber,subject to notable back-diffusion,and that the closed-loop method is reasonably used for porous media with a low effective diffusion coefficient in view of the back-diffusion *** CFD-based simulation is expected to provide guidance for the optimization of the radon exhalation rate measurement method and,thus,the accurate measurement of the radon exhalation rate.

关键词： Radon exhalation Numerical simulation Accumulation chamber

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In-situ measurement via the flow-through method and numerical simulations for radon exhalation during measurements of the radon exhalation rate

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Nuclear Science and Techniques 2024年第7期35卷 192-207页

作者： Ming Xia yong-jun ye Shan-Wei Shang Ting Yu Dai-Jia Chen School of Resources Environment and Safety Engineering University of South ChinaHengyang421001China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang421001China

Small-scale measurements of the radon exhalation rate using the flow-through and closed-loop methods were conducted on the surface of a uranium tailing pond to better understand the differences between the two *** abnormal radon exhalation behavior was observed,leading to computational fluid dynamics(CFD)-based simulations in which dynamic radon migration in a porous medium and accumulation chamber was *** on the in-situ experimental and numerical simulation results,variations in the radon exhalation rate subject to permeability,flow rate,and insertion depth were quantified and *** in-situ radon exhalation rates measured using the flow-through method were higher than those measured using the closed-loop method,which could be explained by the negative pressure difference between the inside and outside of the chamber during the *** consistency of the variations in the radon exhalation rate between the experiments and simulations suggests the reliability of CFD-based techniques in obtaining the dynamic evolution of transient radon exhalation rates for diffusion and convection at the porous medium-air *** synergistic effects of the three factors(insertion depth,flow rate,and permeability)on the negative pressure difference and measured exhalation rate were quantified,and multivariate regression models were established,with positive correlations in most cases;the exhalation rate decreased with increasing insertion depth at a permeability of 1×10^(−11) m^(2).CFD-based simulations can provide theoretical guidance for improving the flow-through method and thus achieve accurate measurements.

关键词： Radon exhalation Flow-through Numerical simulation Accumulation chamber Multivariate regression

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Analysis and optimization of performance parameters of the^(220)Rn chamber in flow-field mode using computational fluid dynamics method

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Nuclear Science and Techniques 2024年第10期35卷 70-85页

作者： Shao-Hua Hu yong-jun ye Zheng-Zhong He De-Tao Xiao Xiang-Yu Xu Jian-Kai Wang Qing-Zhi Zhou School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China

The impact of the radiation dose produced by^(222)Rn/^(220)Rn and its progeny on human health has garnered increasing interest in the nuclear research *** establishment of robust,regulatory,and competent^(220)Rn chambers is crucial for accurately measuring radioactivity ***,studying the uniformity of the^(220)Rn progeny through experimental methods is challenging,because measuring the concentration of^(220)Rn and its progeny in multiple spatial locations simultaneously and in real time using experimental methods is ***,achieving precise control of the concentration of^(220)Rn and its progeny as well as the reliable sampling of the progeny pose significant *** solve this problem,this study uses computational fluid dynamics to obtain the flow-field data of the^(220)Rn chamber under different wind speeds and progenyreplenishment *** analysis of the concentration distribution of the progeny and quantitative analysis of the progeny concentration and uniformity of the progeny concentration are *** research findings indicated that the progeny concentration level is primarily influenced by wind speed and the progeny-complement *** speed also plays a crucial role in determining progeny concentration uniformity,whereas the progeny-complement rate has minimal impact on *** ensure the accuracy of^(220)Rn progeny concentration sampling,we propose a methodology for selecting an appropriate sampling area based on varying progeny *** study holds immense importance for enhancing the regulation and measurement standards of^(220)Rn and its progeny.

关键词： Thoron Progeny Regulatory CFD simulation

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Effect of cholesterol metabolism on hepatolithiasis

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World Journal of Gastroenterology 2025年第1期31卷 157-162页

作者： Lin Zheng Zi-Yu ye jun-Ji Ma Department of Gastroenterology The Second Hospital of Hebei Medical UniversityHebei Key Laboratory of GastroenterologyHebei Institute of GastroenterologyHebei Clinical Research Center for Digestive DiseasesNo.215 Heping West RoadShijiazhuang 050000Hebei ProvinceChina

Surgical intervention is currently the primary treatment for hepatolithiasis;how-ever,some patients still experience residual stones and high recurrence rates after *** metabolism seems to play an important role in hepatoli-thiasis pathogenesis.A high cholesterol diet is one of the significant reasons for the increasing incidence of ***,regular diet and appropriate medical intervention are crucial measures to prevent hepatolithiasis and reduce recurrence rate after *** dietary cholesterol and drugs that increase cholesterol stone solubility are key therapeutic approaches in treating *** article discusses the cholesterol metabolic pathways related to the pathogenesis of hepatolithiasis,as well as food intake and targeted therapeutic drugs.

关键词： Hepatolithiasis Cholesterol metabolism High-fat diet 3-hydroxy-3-methylglutaryl-coenzyme A reductase Interlobular bile duct

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基于Petri Fault Net的磁浮列车悬浮系统故障分析

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系统仿真学报 2007年第A1期19卷 266-270页

作者：龙志强张永焘叶俊国防科技大学磁悬浮工程研究中心湖南长沙410073

随着磁浮列车技术的商业化应用,磁浮列车系统故障诊断越来越受到重视。以中低速磁浮列车为背景,在建立磁浮列车悬浮系统故障模型的基础上,针对磁浮列车悬浮系统的复杂性,将基于Petri Net的故障诊断理论Petri Fault Net应用于磁浮列车悬... 详细信息

随着磁浮列车技术的商业化应用,磁浮列车系统故障诊断越来越受到重视。以中低速磁浮列车为背景,在建立磁浮列车悬浮系统故障模型的基础上,针对磁浮列车悬浮系统的复杂性,将基于Petri Net的故障诊断理论Petri Fault Net应用于磁浮列车悬浮系统的故障诊断中。给出了基于Petri网的最小割集寻找方法;根据磁浮列车2001年以来的运行数据统计,计算出了节点的P概率/T概率;在此基础上进行了故障定位和影响分析。列车的试验运行验证了提出的理论准确性。

关键词： Petri Net 磁浮列车悬浮控制故障诊断

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Development of an ultrahard nanotwinned cBN micro tool for cutting hardened steel

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Science China(Technological Sciences) 2016年第6期59卷 876-881页

作者： CHEN jun Yun JIN Tian ye TIAN yong jun College of Vehicles and Energy Yanshan University College of Mechanical Engineering Yanshan University State Key Laboratory of Metastable Materials Science & Technology Yanshan University

Binderless nanotwinned cubic boron nitride(nt-cBN) synthesized from onion-structured BN precursors under high pressure and high temperature shows a very fine microstructure consisting of densely lamellar nanotwins(average thickness of 4 nm) within nanograins. The unique nanotwinned microstructure offers high hardness, wear resistance, fracture toughness, and thermal stability which are essential for advanced cBN tool materials. Thus, a circular micro tool of nt-cBN was fabricated using femtosecond laser contour machining followed by focused ion beam precision milling. Thereafter turning tests were performed on hardened steel using the studied micro tool. To evaluate the cutting performance, the machined surface quality and subsurface damage of the hardened steel were characterized. The wear mechanism of the nt-cBN micro tool was also investigated. It is found that the fabricated nt-cBN micro tool can generate high quality surface with surface roughness less than 7 nm and nanograin subsurface of about 500 nm deep. In addition, abrasive wear is found to be the dominant wear mechanism of the nt-cBN micro tool in turning hardened steel. These results indicate that nt-cBN has outstanding potential for ultra-precision cutting hardened steel.

关键词： nanotwinned cBN tool fabrication cutting tool micro machining hardened steel

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From chemical mixtures to antibiotic resistance

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Journal of Environmental Sciences 2017年第12期29卷 138-144页

作者： jun ye Christopher Rensing Jianqiang Su yong-Guan Zhu Key Laboratory of Urban Environment and Health Institute of Urban Environment Chinese Academy of Sciences Institute of Environmental Microbiology College of Resources and Environment Fujian Agriculture and Forestry University State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

In real environment, it is unlikely that contaminants exist singly; environmental contamination with chemical mixtures is a norm. However, the impacts of chemical mixtures on environmental quality and ecosystem health have been overlooked in the *** the complex interactions between different contaminants, their relationship with the rise of antibiotic resistance（AR） is an emerging environmental concern. In this paper,we review recent progresses on how chemicals or chemical mixtures promote AR. We propose that, through co-selection, agents causing stress to bacteria may induce AR. The mechanisms for chemical mixtures to promote AR are also discussed. We also propose that,mechanistic understanding of co-selection of chemical mixtures for AR should be a future research priority in environmental health research.

关键词： Chemical mixture Antibiotic resistance Heavy metals Co-selection Cross-resistance Co-regulation

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Linguistic neutrosophic matrix energy and its application in multiple criteria group decision-making

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Journal of Management Analytics 2023年第3期10卷 477-492页

作者： Rui yong Shigui Du jun ye School of Civil and Environmental Engineering Ningbo UniversityNingboPeople’s Republic of China

Matrix energy is an important representation tool of collective ***,it is not applied to various fuzzy and linguistic *** compensate for this gap,this article aims to extend the matrix energy to propose the energy of a linguistic neutrosophic matrix(LNM)for solving a multiple criteria group decision-making(MCGDM)problem,which fully contains LNMs of decisionmaker weights,criteria weights,and alternative *** realize the objective,this study first presents the energy of LNM in view of the true matrix energy,the false matrix energy,and the indeterminate matrix ***,a MCGDM technique is established in view of the LNM energy method in a LNM ***,the developed MCGDM technique using the LNM energy is used to solve the hospital location choice problem in the full LNM ***,the decision results indicate the validity and usability of the established MCGDM technique.

关键词： linguistic neutrosophic matrix linguistic neutrosophic matrix energy linguistic neutrosophic weight group decision making

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Orthopair indeterminate information expression,aggregations and multiattribute decision making method with indeterminate ranges

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Journal of Control and Decision 2022年第1期9卷 80-88页

作者： jun ye Shigui Du Rui yong School of Civil and Environmental Engineering Ningbo UniversityNingboP.R.People’s Republic of China

A neutrosophic number(NN)(d=μ+vI)can flexibly represent the indeterminate information corresponding to values/ranges of the indeterminacy *** the hybrid concept of intuitionistic fuzzy set(IFS)and NN,this study presents an orthopair indeterminate set(OIS),an orthopair indeterminate element weighted arithmetic averaging(OIEWAA)operator and an orthopair indeterminate element weighted geometric averaging(OIEWGA)operator to simplify and generalise the existing IFS and interval-valued IFS expressions and aggregation ***,a multiattribute decision making(DM)approach with indeterminate ranges of decision makers is developed based on the OIEWAA and OIEWGA operators and the score and accuracy functions of orthopair indeterminate elements in OIS ***,the proposed DM approach is applied to a multi-attribute DM example of manufacturing schemes(alternatives)in OIS setting to demonstrate the applicability and flexibility of the proposed DM approach in OIS setting.

关键词： Orthopair indeterminate set orthopair indeterminate element weighted arithmetic averaging operator orthopair indeterminate element weighted geometric averaging operator decision making

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MCDM technique using single-valued neutrosophic trigonometric weighted aggregation operators

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Journal of Management Analytics 2024年第1期11卷 45-61页

作者： jun ye Shigui Du Rui yong School of Civil and Environmental Engineering Ningbo UniversityNingboPeople’s Republic of China

Motivated based on the trigonometric t-norm and t-conorm,the aims of this article are to present the trigonometric t-norm and t-conorm operational laws of SvNNs and then to propose the SvNN trigonometric weighted average and geometric aggregation operators for the modelling of a multiple criteria decision making(MCDM)technique in an inconsistent and indeterminate *** realize the aims,this paper first proposes the trigonometric t-norm and t-conorm operational laws of SvNNs,which contain the hybrid operations of the tangent and arctangent functions and the cotangent and inverse cotangent functions,and presents the SvNN trigonometric weighted average and geometric operators and their ***,an MCDM technique is proposed in view of the presented two aggregation operators in the circumstance of *** the end,an actual case of the choice issue of slope treatment schemes is provided to indicate the practicability and effectivity of the proposed MCDM technique.

关键词： Single-valued neutrosophic number trigonometric t-norm and t-conorm trigonometric weighted aggregation operator decision making

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