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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3798-3811页

作者： Qihua Zhang shan dong Yaoqi Liu Junjie Huang Feng Xiong Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan430074China SINOPEC shanghai Engineering Co. Ltd.Shanghai200120China Faculty of Engineering China University of GeosciencesWuhan430074China

Analyzing rock mass seepage using the discrete fracture network(DFN)flow model poses challenges when dealing with complex fracture *** paper presents a novel DFN flow model that incorporates the actual connections of large-scale ***,this model efficiently manages over 20,000 fractures without necessitating adjustments to the DFN *** geometric analyses,such as identifying connected fractures,dividing the two-dimensional domain into closed loops,triangulating arbitrary loops,and refining triangular elements,are fully *** analysis processes are comprehensively introduced,and core algorithms,along with their pseudo-codes,are outlined and explained to assist readers in their programming *** accuracy of geometric analyses is validated through topological graphs representing the connection relationships between *** practical application,the proposed model is employed to assess the water-sealing effectiveness of an underground storage cavern *** analysis results indicate that the existing design scheme can effectively prevent the stored oil from leaking in the presence of both dense and sparse ***,following extensive modification and optimization,the scale and precision of model computation suggest that the proposed model and developed codes can meet the requirements of engineering applications.

关键词： Discrete fracture network(DFN)flow model Geometric algorithm Fracture flow Water-sealing effect

A Three-Dimensional DEM Method for Trajectory Simulations of Rockfall under Irregular-Shaped Slope Surface and Rock Blocks

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Journal of Earth Science 2024年第1期35卷 306-312页

作者： Liang Chen Weiqian Zeng Xianbiao Wang Yang Ye Yunfeng Ge dongming Gu shan dong Huadong Engineering Corporation Limited Fuzhou 350003China Faculty of Engineering China University of GeosciencesWuhan 430074China Badong National Observation and Research Station of Geohazards China University of GeosciencesWuhan 430074China

0 *** is a common geological hazard that poses a serious threat to residents and infrastructures(Gao et al.,2022;Ye et al.,2022).The precise prediction of rockfall trajectories is essential to the design of protection engineering structures of rockfall(Ma et al.,2021).The discrete element modelling(DEM)is increasingly used to analyse rockfall movement *** et al.(2022)used Rockyfor3D software to obtain the possible trajectory of falling rock blocks.

关键词： rock prediction hazard

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Recent Progress in Fabrication and Structural Design of Thermal Conductive Polymer Composites

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Chinese Journal of Polymer Science 2024年第3期42卷 277-291,I0004页

作者： Yuan-Kai Du Zheng-Xue Shi shan dong Hui Jin Xue Ke Pei Zhao Bing-Bing Jiang Feng You Hubei Key Laboratory of Plasma Chemistry and Advanced Materials School of Material Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Key Laboratory of Green Preparation and Application of Functional Materials Ministry of EducationHubei UniversityWuhan 430062China Institute of Molecular Aggregation Science Tianjin UniversityTianjin 300072China

In recent years, the demand direction for electronic equipment has expanded into embedded and miniaturized devices. The heat radiation problem has become one of the most significant factors for hindering the development of electronic devices. Since heat radiation material is one of the important components in electronic devices, the demand for enhancing thermal conductivity is also increasingly urgent. Research on thermal conductive polymer composites has become a major direction for developing functional composites. This work reviewed the recent progress in the fabrication of thermal conductive polymer composites. Five different structures are presented, including the using of single fillers,hybrid fillers, double threshold percolation structure, segregated structure and other complex multiphase structures. Specifically, the preparation of high-performance thermal conductive polymer composites was introduced through the combination of various thermal conductive ***, the development direction of high thermal conductive polymer composites was briefly explored.

关键词： Thermal conductive polymer Hybrid fillers Polymer composite Thermal resistance

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Proposing a machine learning approach to analyze and predict basic high-temperature properties of iron ore fines and its factors

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Journal of Iron and Steel Research International 2024年第5期31卷 1082-1094页

作者： Qing-ke Sun Yao-zu Wang Jian-liang Zhang Zheng-jian Liu Le-le Niu Chang-dong shan Yun-fei Ma Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing100083China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China

The basic high-temperature properties of iron ore play a crucial role in optimizing sintering and ore blending,but the testing process for these properties is complex and has significant lag time,which cannot meet the actual needs of ore blending.A prediction model for the basic high-temperature properties of iron ore fines was thus proposed based on a combination of machine learning algorithms and genetic ***,the prediction accuracy of different machine learning models for the basic high-temperature properties of iron ore fines was ***,a random forest model optimized by genetic algorithms was built,further improving the prediction accuracy of the *** test results show that the random forest model optimized by genetic algorithms has the highest prediction accuracy for the lowest assimilation temperature and liquid phase fluidity of iron ore,with a determination coefficient of 0.903 for the lowest assimilation temperature and 0.927 for the liquid phase fluidity after *** trained model meets the fluctuation requirements of on-site testing and has been successfully applied to actual production on site.

关键词： Iron ore Basic high-temperature property Machine learning Random forest Genetic algorithm

Mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： Le-le Niu Zheng-jian Liu Jian-liang Zhang Yao-zu Wang Zhen-xing Yang Si-da Li Chang-dong shan Ben Feng School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing Casting Pipe Xinjiang Co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. Ca elements are found in the form of calcite (CaCO3) and dolomite (CaMg(CO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional CaO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore Magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis

Large-scale Discrete Element Modelling of In-situ Direct Shear and Plate Load Tests on Granular Soils

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Journal of Earth Science 2024年

作者： Zhichun Lu shan dong Guodong Liu Marcos Arroyo Xingwei Ren China University of Geosciences Associate Professor， China University of Geosciences Changjiang Institute of Survey，Planning， Design and Research Universitat Politécnica de Catalunya (UPC)

This study unveils a novel and potentially economical particulate discrete element modeling (DEM) technique for large-scale simulation of in-situ direct shear tests (DST) and plate load tests， aimed at accurately determining the shear strength and bearing capacity of granular soil foundations， and exploring the key factors influencing these properties. To overcome the limitations associated with the oversimplification of particle shapes， this work introduces an innovative contact model based on the Hertz contact mechanism that incorporates rolling resistance， enhancing the model’s ability to simulate realistic particle interactions. Guided by Prandtl’s foundation bearing-capacity theory， the dimensions of the foundation model for the DST and plate load tests were meticulously calculated to reflect realistic conditions. DEM simulations showed the peak friction angle from in-situ DST to be consistently lower than laboratory DST， due to a smaller dilatation angle， while proposed loading methods for plate load tests established linear relationships between the foundation’s ultimate bearing capacity and its dimensions， also defining the capacity envelope. Crucially， this study highlights a crucial finding: in-situ direct shear tests (DST) conducted under high normal stress may lead to foundation failure， indicating that excessive normal stress should be avoided to ensure the accuracy of in-situ shear test data and its subsequent applicability in engineering design.

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Application of non-mydriatic fundus photography-assisted telemedicine in diabetic retinopathy screening

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World Journal of Diabetes 2024年第2期15卷 251-259页

作者： Wan Zhou Xiao-Jing Yuan Jie Li Wei Wang Hao-Qiang Zhang Yuan-Yuan Hu shan-dong Ye Department of Endocrinology The First Affiliated Hospital of University of Science and Technology of ChinaDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230001Anhui ProvinceChina Department of Endocrinology Anhui Provincial HospitalAffiliated to Anhui Medical UniversityHefei 230001Anhui ProvinceChina

BACKGROUND Early screening and accurate staging of diabetic retinopathy(DR)can reduce blindness risk in type 2 diabetes ***’s complex pathogenesis involves many factors,making ophthalmologist screening alone insufficient for prevention and ***,endocrinologists are the first to see diabetic patients and thus should screen for retinopathy for early *** To explore the efficacy of non-mydriatic fundus photography(NMFP)-enhanced telemedicine in assessing DR and its various *** This retrospective study incorporated findings from an analysis of 93 diabetic patients,examining both NMFP-assisted telemedicine and fundus fluorescein angiography(FFA).It focused on assessing the concordance in DR detection between these two ***,receiver operating characteristic(ROC)curves were generated to determine the optimal sensitivity and specificity of NMFP-assisted telemedicine,using FFA outcomes as the standard *** In the context of DR diagnosis and staging,the kappa coefficients for NMFPassisted telemedicine and FFA were recorded at 0.775 and 0.689 respectively,indicating substantial intermethod ***,the NMFP-assisted telemedicine’s predictive accuracy for positive FFA outcomes,as denoted by the area under the ROC curve,was remarkably high at 0.955,within a confidence interval of 0.914 to 0.995 and a statistically significant P-value of less than *** predictive model exhibited a specificity of 100%,a sensitivity of 90.9%,and a Youden index of *** NMFP-assisted telemedicine represents a pragmatic,objective,and precise modality for fundus examination,particularly applicable in the context of endocrinology inpatient care and primary healthcare settings for diabetic *** implementation in these scenarios is of paramount significance,enhancing the clinical accuracy in the diagnosis and therapeutic management of *** methodology not only streamlines patient evaluation

关键词： Diabetes Diabetic retinopathy Non-mydriatic fundus photography-assisted telemedicine Fundus fluorescein angiography

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聚合物玻璃化转变太赫兹光谱技术研究进展

光谱学与光谱分析 2024年第10期44卷 2709-2716页

作者：柯智林董冰凌东雄魏东山东莞理工学院机械工程学院广东东莞523808 东莞理工学院电子工程与智能化学院广东东莞523808 中国科学院深圳先进技术研究院广东深圳528055

聚合物玻璃化转变作为非晶聚合物的玻璃态和高弹态之间的转变,对材料性能尤其是力学性能具有重要影响。太赫兹光谱作为一种新型的光谱分析技术,具有非接触、快速和高灵敏度等优势,在聚合物玻璃化转变研究中显示出重要的应用潜力。通过对... 详细信息

聚合物玻璃化转变作为非晶聚合物的玻璃态和高弹态之间的转变,对材料性能尤其是力学性能具有重要影响。太赫兹光谱作为一种新型的光谱分析技术,具有非接触、快速和高灵敏度等优势,在聚合物玻璃化转变研究中显示出重要的应用潜力。通过对近15年来文献中的研究结果进行总结和分析,旨在全面了解太赫兹光谱技术在该领域的应用现状,并展望其未来发展方向。首先介绍了聚合物玻璃化转变的特性,探讨了传统的测量方法以及它们所面临的限制,如热分析法、动态机械分析法和红外光谱法等。为了弥补这些局限性,研究者们开始寻找新的研究手段。太赫兹光谱技术具有同时提供光谱和相位信息的能力,可以直接测量材料的折射率和介电常数,而折射率的变化可以反映聚合物链的自由体积变化,这是太赫兹光谱可以探测聚合物玻璃化转变的根本原因。接着,总结了近年来太赫兹光谱技术在聚合物玻璃化转变研究中的应用进展,对不同聚合物材料的研究结果进行了详细阐述,包括聚甲醛、聚酰胺、聚ε-己内酯、聚乳酸。研究结果表明,太赫兹光谱技术可以精确测定聚合物的玻璃化转变温度,并提供聚合物结构和构象的微观信息,揭示聚合物玻璃化转变机制。进一步,还指出了太赫兹光谱技术存在的问题,包括太赫兹光谱仪的频宽限制和高成本。因此,未来研究需要进一步改进太赫兹源和仪器的性能,开发更有效的数据分析方法,并探索太赫兹光谱技术在工业应用中的潜力。总体而言,太赫兹光谱技术作为一种新兴的研究工具,在聚合物玻璃化转变领域取得了积极的进展,并具备实现聚合物的快速、灵敏检测以及精确结构分析的能力。

关键词：太赫兹光谱聚合物玻璃化温度吸收系数折射率

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Clinical efficacy,bone density,and follow-up in implant and orthodontic treatment for inclined adjacent teeth

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World Journal of Clinical Cases 2024年第24期12卷 5542-5548页

作者： Yi Yang Shun-Cheng Zhou Yi-Hui Ma Xiang Wang Qing-shan dong Department of Stomatology General Hospital of Central Theater CommandWuhan 430012Hubei ProvinceChina

BACKGROUND Tooth defects can cause elongation of occlusal teeth,leading to insufficient repair *** combination of dental implant restoration and orthodontic treatment of oblique adjacent teeth has a significant therapeutic *** To explore clinical efficacy,bone density,and follow-up of implant and orthodontic treatment for patients with inclined adjacent *** In total,98 patients with oblique adjacent teeth were randomly assigned to implant restoration combined with orthodontic treatment(group A,n=49)or to receive implant restoration alone(group B,n=49).Changes in alveolar ridge bone density and apical bone density were observed before and after treatment in the two *** in chewing function and language function were compared between the two groups of ***-up lasted for 12 mo after repair to observe any adverse reactions in the oral *** The clinical effective rates of group A and group B were 97.96%and 85.71%,respectively,with group A having a higher clinical effective rate than group *** treatment,the bone density of the alveolar ridge and apical bone in both groups decreased compared to before treatment,while the chewing and language functions *** changes in various indicators in group A were more *** treatment,the satisfaction rate of group A(97.96%)was higher than that of group B(79.59%).The incidence of adverse reactions in group A(2.04%)was lower than that in group B(24.49%).CONCLUSION The amalgamation of implant restoration and orthodontic treatment for adjacent tilted teeth demonstrates notable clinical efficacy,diminishes alveolar bone resorption,and fosters patient functional rehabilitation while exhibiting negligible adverse reactions.

关键词： Dental implant restoration Orthodontic correction Tilt adjacent teeth Clinical curative effect Alveolar bone mineral density

一维耦合腔晶格中磁子-光子拓扑相变和拓扑量子态的调制

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物理学报 2024年第4期73卷 170-177页

作者：李锦芳何东山王一平咸阳师范学院物理与电子工程学院咸阳712000 西北农林科技大学理学院杨凌712100

本文提出了基于耦合腔的一维晶格理论方案,其中每个晶胞包含微波腔光子和磁子,通过调控磁子与微波光子的耦合来研究系统中的拓扑相变和拓扑量子通道.首先,分析了在奇偶晶格数情况下,系统能谱和边缘态的特征,并发现边缘态分布可以展示反... 详细信息

本文提出了基于耦合腔的一维晶格理论方案,其中每个晶胞包含微波腔光子和磁子,通过调控磁子与微波光子的耦合来研究系统中的拓扑相变和拓扑量子通道.首先,分析了在奇偶晶格数情况下,系统能谱和边缘态的特征,并发现边缘态分布可以展示反转过程,可以实现多通道拓扑量子态传输;其次,考虑存在缺陷和无序的扰动,发现它们在较小值范围内,可以使能带产生波动和翻转现象,但边缘状态对其是鲁棒的,这表明边缘态受到系统的拓扑保护.该研究结果为研究拓扑磁子-光子提供了一条新途径,将在量子信息处理中有着广阔的应用前景.

关键词：量子光学腔量子电动力学拓扑绝缘体量子态

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