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Preparation and properties of ZrO_(2)-strengthened porous mullite insulation materials using Y_(2)O_(3) additive

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Journal of Iron and Steel Research International 2024年第6期31卷 1514-1521页

作者： Wang-zhi Yu Yi-hong Shi Ping Liu Yong-wan wu Cheng-hao Song Xian-gong Deng Xiang Ding Song-lin Ran Yi Zhang Hai-jun Zhang Hai-liang Deng Advanced Ceramics Research Center School of Materials Science and EngineeringAnhui University of TechnologyMa'anshan 243002AnhuiChina The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

ZrO_(2)-strengthened porous mullite insulation materials were prepared by foaming technology utilizing ZrSiO_(4) and Al_(2)O_(3) as primary materials and Y_(2)O_(3) as an *** effects of Y_(2)O_(3) contents on the phase composition,microstructure,mechanical properties,and heat conductivity of the porous mullite insulation materials were investigated.A suitable Y_(2)O_(3) content could promote phase transition of monoclinic ZrO_(2)(m-ZrO_(2))to tetragonal ZrO_(2)(t-ZrO_(2)),reduce pore size,and improve the strengths of as-prepared *** cold crushing strength and bending strength of as-prepared specimens with a 119µm spherical pore size using 6 wt.%Y_(2)O_(3) were 35.2 and 13.0 MPa,respectively,with a heat conductivity being only 0.248 W/(m K).

关键词： Porous mullite insulation material Zirconium oxide Y_(2)O_(3) Mechanical property Heat conductivity

A Power Data Anomaly Detection Model Based on Deep Learning with Adaptive Feature Fusion

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Computers, Materials & Continua 2024年第6期79卷 4045-4061页

作者： Xiu Liu liang Gu Xin Gong Long An Xurui Gao Juying wu State Grid Information&Telecommunication Co.of SEPC Big Data CenterTaiyuan030000China

With the popularisation of intelligent power,power devices have different shapes,numbers and *** means that the power data has distributional variability,the model learning process cannot achieve sufficient extraction of data features,which seriously affects the accuracy and performance of anomaly ***,this paper proposes a deep learning-based anomaly detection model for power data,which integrates a data alignment enhancement technique based on random sampling and an adaptive feature fusion method leveraging dimension *** at the distribution variability of power data,this paper developed a sliding window-based data adjustment method for this model,which solves the problem of high-dimensional feature noise and low-dimensional missing *** address the problem of insufficient feature fusion,an adaptive feature fusion method based on feature dimension reduction and dictionary learning is proposed to improve the anomaly data detection accuracy of the *** order to verify the effectiveness of the proposed method,we conducted effectiveness comparisons through elimination *** experimental results show that compared with the traditional anomaly detection methods,the method proposed in this paper not only has an advantage in model accuracy,but also reduces the amount of parameter calculation of the model in the process of feature matching and improves the detection speed.

关键词： Data alignment dimension reduction feature fusion data anomaly detection deep learning

Electrical discharge and arc milling with automatic tracking of optimal flushing direction:A novel high-efficiency compound machining method

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Chinese Journal of Aeronautics 2024年第3期37卷 351-364页

作者： Xinlei wu Yonghong LIU Pengxin ZHANG liang QI Dege LI Chi MA Renjie JI College of Mechanical and Electronic Engineering China University of Petroleum(East China)Qingdao 266580China School of Mechanical and Power Engineering Nanjing Tech UniversityNanjing 211816China

The arc milling method has the advantages of high machining efficiency and low cost and is independent of the strength and hardness of machined ***,frequent electrode back-offs and the risk of workpiece burning may occur if erosion products are not removed *** this study,it was found that the flushing method of the working medium had a significant impact on the machining performance of arc *** on this,a novel highefficiency compound machining method of electrical discharge and arc milling with automatic tracking of the optimal flushing direction was *** automatic tracking optimizer for external working medium injection was designed to determine the optimal external flushing direction according to the feed *** influence of flushing methods,working mediums,and machining parameters on the machining efficiency,tool electrode wear rate,machining error,and surface integrity of titanium alloys were *** results indicated that better machining performance and environmental friendliness were achieved using the compound flushing method of outer compressed air and inner deionized ***,the automatic tracking flushing method in the opposite direction of the feed direction showed superior results compared to other *** material removal rate with the opposite direction injection could be increased up to 1.62 times that of the same direction,and the relative electrode wear rate could be reduced by 14.76%.This novel method has broad application prospects for machining parts with difficult-to-cut materials in aerospace and military industries.

关键词： Arc milling Dielectric Difficult-to-cut materials Electric discharge machining Erosion Material removal rate

Metal/covalent organic frameworks for aqueous rechargeable zinc-ion batteries

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Science China Chemistry 2024年第1期67卷 247-259页

作者： Hu hong Xun Guo Jiaxiong Zhu Zhuoxi wu Qing Li Chunyi Zhi Department of Materials Science and Engineering City University of Hong KongHong Kong 999077China

Lithium-ion batteries(LIBs)have become one of the most successful energy storage systems due to their high operating voltage,high energy density,and long cycle ***,with the widespread use of LIBs in recent decades,lithium resources are at risk of being ***,it is necessary to find a substitute for LIBs to meet the needs of future large-scale energy storage *** of their competitiveness,low cost,and high safety,aqueous rechargeable zinc-ion batteries(ARZIBs)are regarded as promising components in the post-lithium-ion-battery *** the tunable composition,ordered porous channels,and controllable structure of metal-organic frameworks(MOFs)and covalent organic frameworks(COFs),these frameworks are viewed as potential materials for developing high-performance *** this review,we focus on the recent developments in the applications of MOF-/COF-based materials in ARZIBs,including in electrode materials,anode modifications,separators,and solid *** then focus on the critical factors and optimization techniques of MOF-/COF-based materials that affect the performance of ***,we conclude with some projections for the expansion of ARZIBs containing MOF-/COF-based materials.

关键词： metal/covalent organic frameworks aqueous zinc-ion batteries electrode materials anode modifications separators electrolytes

Mars exploration——In situ K-Ar dating of jarosite

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Science China Earth Sciences 2024年第3期67卷 641-656页

作者： Jing YANG Dewen ZHENG Ying wu hong CHEN Li YANG Bin ZHANG Key Laboratory of Active Tectonics and Geological Safety Ministry of Natural ResourcesInstitute of GeomechanicsChinese Academy of Geological SciencesBeijing 100081China State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake AdministrationBeijing 100029China Institute of Earth Sciences China University of GeosciencesBeijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029Chin

To accurately determine the chronological framework of climatic variations recorded by various Martian terrains, the absolute ages of Martian events and cratering rate need to be constrained by either in situ dating or returned samples. In situ K-Ar dating is currently a more plausible dating technique as compared with sample return. Jarosite(KFe_(3)[SO_(4)]_(2)[OH]_(6)) is the only confirmed K sulfate mineral that is widely present on Mars, as indicated by in situ detection, orbital remote sensing, and meteorite studies. Jarosite can be used for precise K-Ar and (40)Ar/(39)Ar dating. The preservation of jarosite on Mars provides information about the nature and duration of aqueous processes on the Martian surface. Different ages of Martian jarosite represent the key to constraining the transition from Martian surface water activity to arid climatic conditions. This paper summarizes recent advances in our knowledge of the spatial distribution of Martian jarosite, its mineralogical properties and stability on Mars, the Ar diffusion kinetics of jarosite, and the current status of in situ K-Ar dating. Moreover, we examine the key scientific issues to be addressed for in situ K-Ar dating of jarosite and Martian sample return missions, and discuss future research directions.

关键词： Mars Jarosite In situ K-Ar dating Ar diffusion Stability

Liquefaction susceptibility and deformation characteristics of saturated coral sandy soils subjected to cyclic loadings-a critical review

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 261-296页

作者： Chen Guoxing Qin You Ma Weijia liang Ke wu Qi C.Hsein Juang Institute of Geotechnical Engineering Nanjing Tech UniversityNanjing 210009China Civil Engineering and Earthquake Disaster Prevention Center of Jiangsu Province Nanjing 210009China School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China College of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 210016China Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA

Coral sandy soils widely exist in coral island reefs and seashores in tropical and subtropical *** to the unique marine depositional environment of coral sandy soils,the engineering characteristics and responses of these soils subjected to monotonic and cyclic loadings have been a subject of intense interest among the geotechnical and earthquake engineering *** paper critically reviews the progress of experimental investigations on the undrained behavior of coral sandy soils under monotonic and cyclic loadings over the last three *** focus of coverage includes the contractive-dilative behavior,the pattern of excess pore-water pressure(EPWP)generation and the liquefaction mechanism and liquefaction resistance,the small-strain shear modulus and strain-dependent shear modulus and damping,the cyclic softening feature,and the anisotropic characteristics of undrained responses of saturated coral sandy *** particular,the advances made in the past decades are reviewed from the following aspects:(1)the characterization of factors that impact the mechanism and patterns of EPWP build-up;(2)the identification of liquefaction triggering in terms of the apparent viscosity and the average flow coefficient;(3)the establishment of the invariable form of strain-based,stress-based,or energy-based EPWP ratio formulas and the unique relationship between the new proxy of liquefaction resistance and the number of cycles required to reach liquefaction;(4)the establishment of the invariable form of the predictive formulas of small strain modulus and strain-dependent shear modulus;and(5)the investigation on the effects of stress-induced anisotropy on liquefaction susceptibility and dynamic deformation *** gained through the critical review of these advances in the past decades offer a perspective for future research to further resolve the fundamental issues concerning the liquefaction mechanism and responses of coral sandy sites subjecte

关键词： liquefaction susceptibility dynamic deformation characteristics coral sandy soil cyclic loading review and prospect

Leveraging Uncertainty for Depth-Aware Hierarchical Text Classification

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Computers, Materials & Continua 2024年第9期80卷 4111-4127页

作者： Zixuan wu Ye Wang Lifeng Shen Feng Hu hong Yu Chongqing Key Laboratory of Computational Intelligence Chongqing University of Posts and TelecommunicationsChongqing400000China Division of Emerging Interdisciplinary Areas Hong Kong University of Science and TechnologyHong Kong999077China

Hierarchical Text Classification(HTC)aims to match text to hierarchical *** methods overlook two critical issues:first,some texts cannot be fully matched to leaf node labels and need to be classified to the correct parent node instead of treating leaf nodes as the final classification ***,error propagation occurs when a misclassification at a parent node propagates down the hierarchy,ultimately leading to inaccurate predictions at the leaf *** address these limitations,we propose an uncertainty-guided HTC depth-aware model called ***,we design an early stopping strategy with uncertainty to identify incomplete matching between text and labels,classifying them into the corresponding parent node *** approach allows us to dynamically determine the classification depth by leveraging evidence to quantify and accumulate *** results show that the proposed DepthMatch outperforms recent strong baselines on four commonly used public datasets:WOS(Web of Science),RCV1-V2(Reuters Corpus Volume I),AAPD(Arxiv Academic Paper Dataset),and ***,on the BGC dataset,it improvesMicro-F1 andMacro-F1 scores by at least 1.09%and 1.74%,respectively.

关键词： Hierarchical text classification incomplete text-label matching uncertainty depth-aware early stopping strategy

Enhanced interfacial charge transfer on Bi metal@defective Bi_(2)Sn_(2)O_(7) quantum dots towards improved full-spectrum photocatalysis:A combined experimental and theoretical investigation

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Chinese Chemical Letters 2024年第6期35卷 507-514页

作者： Huizhong wu Ruiheng liang Ge Song Zhongzheng Hu Xuyang Zhang Minghua Zhou Tianjin Key Laboratory of Environmental Technology for Complex Trans-Media Pollution College of Environmental Science and EngineeringNankai UniversityTianjin 300350China Key Laboratory of Pollution Process and Environmental Criteria Ministry of EducationCollege of Environmental Science and EngineeringNankai UniversityTianjin 300350China

To mitigate the water pollution problem by photocatalytic degradation of typical antibiotics of tetracycline(TC),we prepared defective Bi_(2)Sn_(2)O_7(BSO)quantum dots(QDs)with a full spectral response due to Bi metal deposition,using a one-pot hydrothermal method,labeled as Bi@*** optimized Bi@BSOOV showed 73.4% removal of TC in 1 h under irradiation with a 50 W LED lamp in the wavelength band in the visible-near-infrared(vis-NIR)light,a rate that is substantially greater than that of pure BSO(14.7%).The synergistic interaction of Bi metal and oxygen vacancies(OVs)is crucial to boosting photocatalytic *** near-infrared region of the photo-response is extended by the surface plasmon resonance(SPR)effect of Bi metal,enhancing the photocatalytic performance and dramatically raising the efficiency of solar energy *** addition to inducing defect levels in BSO,the OVs also activate the surface adsorbed O_(2) to promote the production of·O_(2)^(-)and ^(1)O_(2).DFT calculations reveal that Bi metal and OVs can mutually tune the charge transfer *** the one hand,Bi metal can act as both a charge transfer bridge and an electron donor to assist charge *** the other hand,OVs-induced defect levels allow electrons that leap to the conduction band(CB)to first leap from the valence band(VB)to the defect levels,notably improving interfacial charge separation and *** concept of design executed in this study for altering the catalyst by introducing both OVs and Bi metal can provide a rational design idea and potential insight for improving the photocatalytic activity for environmental applications.

关键词： Bi metal Bi_(2)Sn_(2)O_7 quantum dots Surface plasmon resonance Oxygen vacancies

Mid-infrared computational temporal ghost imaging

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Light(Science & Applications) 2024年第6期13卷 1088-1097页

作者： Han wu Bo Hu Lu Chen Fei Peng Zinan Wang Goery Genty Houkun liang College of Electronics and Information Engineering Sichuan UniversityChengduSichuan610064China College of Electrical Engineering Sichuan UniversityChengduSichuan610064China Key Lab of Optical Fiber Sensing&Communications University of Electronic Science&Technology of ChinaChengduSichuan611731China Laboratory of Photonics Tampere UniversityFI-33014TampereFinland

Ghost imaging in the time domain allows for reconstructing fast temporal objects using a slow *** technique involves correlating random or pre-programmed probing temporal intensity patterns with the integrated signal measured after modulation by the temporal ***,the implementation of temporal ghost imaging necessitates ultrafast detectors or modulators for measuring or pre-programming the probing intensity patterns,which are not available in all spectral regions especially in the mid-infrared ***,we demonstrate a frequency downconversion temporal ghost imaging scheme that enables to extend the operation regime to arbitrary wavelengths regions where fast modulators and detectors are not *** approach modulates a signal with temporal intensity patterns in the near-infrared and transfers the patterns to an idler via difference-frequency generation in a nonlinear crystal at a wavelength where the temporal object can be *** a proof-of-concept,we demonstrate computational temporal ghost imaging in the mid-infrared with operating wavelength that can be tuned from 3.2 to 4.3μ*** scheme is flexible and can be extended to other *** results introduce new possibilities for scan-free pump-probe imaging and the study of ultrafast dynamics in spectral regions where ultrafast modulation or detection is challenging such as the mid-infrared and THz regions.

关键词： ghost Ghost scheme