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Automatic detection and assessment of crack development in ultra-high performance concrete in the spatial and Fourier domains

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 350-364页

作者： Jixing CAO yao ZHANG Haijie HE Weibing PENG Weigang ZHAO Zhiguo yan Hehua ZHU School of Safety Engineering and Emergency Management Shijiazhuang Tiedao UniversityShijiazhuang 050043China College of Civil Engineering and Architecture Zhejiang UniversityHangzhou 310058China College of Civil and Architectural Engineering Taizhou UniversityTaizhou 318000China College of Civil Engineering and Architecture Zhejiang University of TechnologyHangzhou 310014China Department of Geotechnical Engineering Tongji UniversityShanghai 200092China

Automatic detection and assessment of surface cracks are beneficial for understanding the mechanical performance of ultra-high performance concrete(UHPC).This study detects crack evolution using a novel dynamic mode decomposition(DMD)*** this method,the sparse matrix‘determined’from images is used to reconstruct the foreground that contains cracks,and the global threshold method is adopted to extract the crack *** application of the DMD method to the three-point bending test demonstrates the efficiency in inspecting cracks with high ***,the geometric features,including the area and its projection in two major directions,are evaluated over *** relationship between the geometric properties of cracks and load-displacement curves of UHPC is *** to the irregular shape of cracks in the spatial domain,the cracks are then transformed into the Fourier domain to assess their *** indicate that crack patterns in the Fourier domain exhibit a distinct concentration around a central ***,the power spectral density of cracks exhibits an increasing trend over *** investigation into crack evolution in both the spatial and Fourier domains contributes significantly to elucidating the mechanical behavior of UHPC.

关键词： dynamic mode decomposition ultra-high performance concrete crack detection geometric features Fourier domain

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Full-Stokes metasurface polarimetry requiring only a single measurement

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Photonics Research 2024年第3期12卷 514-521页

作者： CHENGLONG ZHENG HUI LI JINGYU LIU MENGGUANG WANG HUAPING ZANG yan ZHANG JIANQUAN yao Key Laboratory of Material Physics Ministry of EducationSchool of Physics and MicroelectronicsZhengzhou UniversityZhengzhou 450052China Key Laboratory of Opto-Electronics Information Technology(Tianjin University) Ministry of EducationSchool of Precision Instruments and Opto-Electronics EngineeringTianjin UniversityTianjin 300072China Beijing Key Laboratory for Metamaterials and Devices Key Laboratory of Terahertz OptoelectronicsMinistry of Educationand Beijing Advanced Innovation Center for Imaging TechnologyDepartment of PhysicsCapital Normal UniversityBeijing 100048China State Key Laboratory of Modern Optical Instrumentation College of Optical Science and EngineeringZhejiang UniversityHangzhou 310027China

Polarization is crucial in various fields such as imaging,sensing,and substance detection.A compact,fast,and accurate polarization detection device is vital for these ***,we demonstrate a multifocus metalens for terahertz polarization detection that requires only a single measurement to obtain complete polarization parameters and reconstruct the polarization state of the incident *** individual subarrays of this metalens convert each of the six polarized components into the same polarization,which in turn links the Stokes parameters to these six *** incident linear polarizations and elliptical polarizations are characterized by Stokes parameters and polarization *** and experimental results show that the scheme can accurately detect the incident polarization with a single *** proposed metasurface polarimetry may find applications in the fields of real-time terahertz detection and integrated optics.

关键词： field incident polar

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Mechanism of a dual-phase Ti-Nb alloy exhibiting near-linear elastic deformation

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Rare Metals 2024年第5期43卷 2282-2289页

作者： yan Guo Wang Ding Wen Ma Shun Guo Hao-Dong Meng Nian-yao Xu School of Automotive Engineering Changzhou Institute of TechnologyChangzhou 213032China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China Youke Publishing Co. LtdChina Grinm Group Co.LtdBeijing 100088China

In this work,the underlying mechanism responsible for the near-linear elastic deformation behavior of a dual-phase Ti-Nb alloy consisting of β and α'' phase with large recoverable strain was systematically *** on in situ synchrotron X-ray diffraction(SXRD)analyses,it was found that besides intrinsic elastic deformation,a slight reversible β-α'' stress-induced martensitic(SIM)transformation,which proceeded in a consecutive mode under the retarding effect of micro-defects,took place during the near-linear elastic *** unloading,a small amount of residual macroscopic strain remained in the specimen due to the incomplete reverse α''→β transformation on *** high near-linear elastic deformability of the cold drawing(CD)Ti-Nb alloy has been revealed to be attributed to the coupling actions of intrinsic elasticity as well as the consecutive and reversible β-α'' SIM *** research may contribute to a new avenue for the design and development of novel dual-phase Ti-based alloys with desirable elastic deformability.

关键词： Titanium alloys Dual-phase Near-linear elastic deformation Martensitictransformation

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Hydrogen release of NaBH_(4) below 60 ℃ with binary eutectic mixture of xylitol and erythritol additive

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Chinese Journal of Chemical Engineering 2024年第7期71卷 225-234页

作者： Yugang Shu Jiaguang Zheng Chengguo yan Ao Xia Meiling Lv Zhenxuan Ma Zhendong yao School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai UniversityTianjin 300071China College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China

NaBH_(4) was widely regarded as a low-cost hydrogen storage material due to its high-mass hydrogen capacity of approximately 10.8%(mass)and high volumetric hydrogen capacity of around 115 g·L^(–1).However,it exhibits strong stability and requires temperatures above 500℃ for hydrogen release in practical *** this study,two polyhydric alcohols,xylitol and erythritol(XE),were prepared as a binary eutectic sugar alcohol through a grinding-melting *** binary eutectic sugar alcohol was used as a proton-hydrogen carrier to destabilize NaBH_(4).The 19NaBH_(4)-16XE composite material prepared by ball milling could start releasing hydrogen at 57.5℃,and the total hydrogen release can reach over 88.8%(4.45%(mass))of the theoretical *** the 19NaBH_(4)-16XE composite was pressed into solid blocks,the volumetric hydrogen capacity of the block-shaped composite could reach 67.2 g·L^(–1).By controlling the temperature,the hydrogen desorption capacity of the NaBH_(4)-XE composite material was controllable,which has great potential for achieving solid-state hydrogen production from NaBH_(4).

关键词： Hydrogen Desorption Binary mixture NaBH_(4) Xylitol Erythritol

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Experimental study on temperature fluctuations on plate surface induced by coaxial-jet flow

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Nuclear Science and Techniques 2024年第5期35卷 139-153页

作者： Xue-yao Xiong Zun-Quan Liu Guo-yan Zhou Xing Luo Shan-Tung Tu Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science and TechnologyShanghai 200237China Institute of Thermodynamics Gottfried Wilhelm Leibniz University Hannover30823 GarbsenGermany

In nuclear reactors,temperature fluctuations of fluids may cause fatigue damage to adjacent structures;this is referred to as thermal *** on thermal striping in the upper plenum has mainly focused on fluid *** experimental studies have been reported on solid structures in a fluid field with a coaxial *** study entailed an experimental study of the temperature fluctuations in the fluid and on a plate surface caused by a coaxial *** temperature fluctuations of the fluid and plate surfaces located at different heights were *** cause of the temperature fluctuation was analyzed using a transient temperature *** results show that the mixing of the hot and cold fluids gradually becomes uniform in the positive axial *** average surface temperatures tended to be *** the jet reaches the plate surface,the swing of the jet center,contraction and expansion of the cold jet,and changes in the jet shape result in temperature *** intensity of the temperature fluctuation was affected by the *** attention should be paid when the plate is located at a lower height,and between the hot and cold-fluid nozzles.

关键词： Temperature fluctuation Thermal striping Coaxial jet Thermal mixing The upper plenum of nuclear reactor

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Research on the identification of the production origin of Angelica dahurica using LIBS technology combined with machine learning algorithms

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Optoelectronics Letters 2024年第3期20卷 171-176页

作者： SUN Jiaxing LI Honglian yao Yuhang yan Qiongyan DONG Fang College of Quality and Technology Supervising Hebei UniversityBaoding 071000China National and Local Joint Engineering Center of Measuring Instruments and Metrology Systems Baoding 071000China Key Laboratory of Energy Measurement and Safety Detection Technology in Hebei Province Baoding 071000China

The origin of Angelica dahurica medicinal herbs varies, and their pharmacological effects also differ. In order to achieve rapid and accurate identification of the origin of Angelica dahurica medicinal herbs, this study utilizes laser induced breakdown spectroscopy(LIBS) technology combined with machine learning algorithms to identify the original source of Angelica dahurica. Sliced samples of Angelica dahurica were taken from four regions: Hebei, Henan, Zhejiang, and Sichuan. The spectral data from the sliced samples were used as features, and different algorithms including support vector machine(SVM), back propagation(BP) neural network, genetic algorithm-back propagation(GA-BP) neural network, particle swarm optimization-back propagation(PSO-BP) neural network, convolutional neural network(CNN), and CNN-SVM were employed to classify the origin of Angelica dahurica samples.

关键词： neural origin network

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Unraveling engineering disturbance effects on deformation in red-bed mudstone railway cuttings:incorporating crack-facilitated moisture diffusion

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Journal of Mountain Science 2024年第5期21卷 1663-1682页

作者： HUANG Kang DAI Zhangjun yan Chengzeng yao Junkai CHI Zecheng CHEN Shanxiong State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China Faculty of Engineering China University of GeosciencesWuhan 430074China International Joint Research Center for Deep Earth Drilling and Resource Development China University of GeosciencesWuhan 430074China China Academy of Railway Sciences Corporation Limited Beijing 100081China

Red-bed mudstone, prevalent in southwest China, poses a formidable challenge due to its hydrophilic clay minerals, resulting in expansion, deformation, and cracking upon exposure to moisture. This study addresses uplift deformation disasters in high-speed railways by employing a moisture diffusion-deformation-fracture coupling model based on the finite-discrete element method(FDEM). The model integrates the influence of cracks on moisture diffusion. The investigation into various excavation depths reveals a direct correlation between depth and the formation of tensile cracks at the bottom of the railway cutting. These cracks expedite moisture migration, significantly impacting the temporal and spatial evolution of the moisture field. Additionally, crack expansion dominates hygroscopic deformation, with the lateral coordinate of the crack zone determining peak vertical displacement. Furthermore, key factors influencing deformation in railway cuttings, including the swelling factor and initial moisture content at the bottom of the cutting, are explored. The number of tensile and shear cracks increases with greater excavation depth, particularly concerning shear cracks. Higher swelling factors and initial moisture contents result in an increased total number of cracks, predominantly shear cracks. Numerical calculations provide valuable insights, offering a scientific foundation and directional guidance for the precise prevention, control, prediction, and comprehensive treatment of mudstone-related issues in high-speed railways.

关键词： Red-bed mudstone Railway cutting FDEM Moisture diffusion Deformation Crack

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Disastrous effects of climate change on High Mountain Asia

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Advances in Climate Change Research 2024年第3期15卷 365-366页

作者： Peng CUI yao-Ming MA yan WANG Bin-BinWANG Institute of Geographic Sciences and Natural Resources Research The Chinese Academy of Sciences(CAS)Beijing 100101China Institute of Mountain Hazards and Environment CASChengdu 610041China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad 45320Pakistan State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchCASBeijing 100101China

High Mountain Asia(HMA),encompassing the Tibetan Plateau and the surrounding high mountain ranges of the Hindu Kush and Tianshan,is a region characterised by large terrain,complex topography and the interplay of vario... 详细信息

关键词： terrain Tianshan Tibetan

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Perioperative and long-term results of ultrasonography-guided single-and multiple-tract percutaneous nephrolithotomy for staghorn calculi

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World Journal of Clinical Cases 2024年第7期12卷 1243-1250页

作者： Rui-Xiang Cheng Ni Dai yan-Min Wang Pei Qi fen Chen Department of Urology Wuhan Ninth HospitalWuhan 430081Hubei ProvinceChina Department of Urinary Pain Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Pre-hospital Emergency Department Wuhan Puren HospitalWuhan 430081Hubei ProvinceChina Department of Orthopedic Trauma Surgery Wuhan Hankou HospitalWuhan 430000Hubei ProvinceChina Department of Ultrasound Hubei Provincial Hospital of Integrated Traditional Chinese and Western MedicineWuhan 430015Hubei ProvinceChina

BACKGROUND It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical *** recent clinical studies have shown that multi-tract percutaneous nephrolithotomy(MPCNL)has a similar stone free rate(SFR)as standard percutaneous nephrolithotomy(S-PCNL).As a result,M-PCNL was also recommended as a treatment option for staghorn *** To examine the perioperative and long-term results of ultrasonography-guided single-and *** This was a retrospective cohort *** March 2021 and January 2022,the urology department of our hospital selected patients for the treatment of staghorn calculi using percutaneous *** primary outcomes were com plication rate and SFR,and the characteristics of patients,operative parameters,laboratory measurements were also *** In total,345 patients were enrolled in the study(186 in the S-PCNL group and 159 in the M-PCNL group).The SFR in the M-PCNL group was significantly higher than that in the S-PCNL group(P=0.033).Moreover,the incidence rates of hydrothorax(P=0.03)and postoperative infection(P=0.012)were higher in the M-PCNL group than in the S-PCNL *** regression analysis demonstrated that post-operative white blood cell count(OR=2.57,95%CI:1.90-3.47,P<0.001)and stone size(OR=1.59,95%CI:1.27-2.00,P<0.001)were associated with a higher overall complication rate in the S-PCNL *** mass index(OR=1.22,95%CI:1.06-1.40,P=0.004)and stone size(OR=1.70,95%CI:1.35-2.15,P<0.001)were associated with increased overall complications in the M-PCNL *** Multiple access tracts can facilitate higher SFR while slightly increasing the incidence of acceptable complications.

关键词： Single-tract percutaneous nephrolithotomy Multiple-tract percutaneous nephrolithotomy Staghorn calculi Ultrasonography

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Defects in the grain interiors of 3 mol%yttria-stabilized tetragonal zirconia polycrystal ceramics with 0.25 wt%alumina

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Journal of Advanced Ceramics 2024年第4期13卷 469-477页

作者： yan Xiong Lian Luo yao Cheng Zhi Liu Qi Liu Weimin Wang Wei Ji School of Materials&Chemical Engineering Hubei Province Key Laboratory of Green Materials for Light IndustryHubei University of TechnologyWuhan 430068China Fujian Institute of Research on the Structure of Mater Chinese Academy of SciencesFuzhou 350002China Jiangxi Provincial Engineering Research Center for Multifunction Zirconia Materials Jiangxi Size Materials Co.Ltd.Jiujiang 332500China State Key Laboratory of Advance Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

The presence of high-density defects is rarely observed in bulk 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3Y-TZP)ceramics obtained through conventional pressureless *** the present work,fine-grained dense 147 nm 3Y-TZP ceramics were prepared by pressureless sintering of commercial 0.25 wt%alumina-doped zirconia powders at 1300℃.A novel discovery was reported in which large amounts of defects were present in the grain interiors of the *** phenomenon was further examined using three types of powder samples,and the reasons for defect formation were investigated by microstructural characterization using high-resolution transmission electron microscopy(HRTEM)analysis and Rietveld *** results confirmed the essential dependence of the defect formation on the alumina *** authors attributed the defect formation to the significant difference in ionic radii of the solvent and solute during the dissolution of alumina into the zirconia *** sintering kinetics were proposed to be enhanced by the presence of substantial defects,which consequently favored the low-temperature sintering of the alumina-doped zirconia ceramics.

关键词： 3 mol%yttria-stabilized tetragonal zirconia polycrystal(3Y-TzP)ceramics alumina addition microstructure defect

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