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2nd International Symposium on Frontiers of Mechanical and Material Engineering, MME 2024

作者： Liu, Haiyun Xiang, Zhi Wang, Lei Wu, Zuhang Wang, Yuan Zhejiang Academy of Special Equipment Science Hangzhou310000 China Key Laboratory of Special Equipment Safety Testing Technology of Zhejiang Province Hangzhou310000 China Hangke Technology Co. LTD Hangzhou310000 China

A boiler economizer is in continuous operation during several burst pipes. Burst tubes are located near the elbow below the weld, and the weld on both sides of the tube wall is thinning seriously. There is a flue gas formation vortex in the furnace chamber;the outer wall of the tubes is thicker ash, and fins and tubes are corroded to varying degrees. This study employed meticulous macroscopic observation, precise chemical composition analysis, detailed metallography, advanced scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) to determine the causes of the coal economizer tube burst and tube wall thinning, ensuring the accuracy of the findings. The chemical composition, microstructure, and grain size of the base material met the requirements of the relevant standards. The heat-affected zone and weld seam show the Widmannstatten structure, a superheated tissue caused by excessive heat input during welding. The outer wall of the pipe corrosion is more serious, resulting in serious wall thinning, and ultimately, the pipe bursts, unable to withstand the pressure inside the pipe. It was eventually determined that the cause of the pipe burst was that the operating temperature of the economizer was close to the dew point, and the flue gas contained sulfur dioxide, sulfur trioxide, and hydrogen chloride that met water vapor at that temperature to form acid. Acid on the outer wall of the pipe was caused by flue gas dew point corrosion, seriously causing the pipe wall to thin. When the pipe wall is thinned to a certain extent due to corrosion, it cannot withstand the pressure inside the pipe, and rupture will occur. © 2024 Institute of Physics Publishing. All rights reserved.

关键词： Sulfur dioxide

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Discovery of prenylated indole alkaloid and natural xanthone from cold-seep sediment derived fungus Talaromyces funiculosus SD-523

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Journal of Oceanology and Limnology 2023年第3期41卷 1152-1158页

作者： Yanan WANG Xiaoming LI Fengyi LÜ Suiqun YANG Linghong MENG Bingui WANG CAS and Shandong Province Key Laboratory of Experimental Marine Biology Institute of OceanologyChinese Academy of SciencesQingdao 266071China College of Marine Science University of Chinese Academy of SciencesBeijing 100049China Laboratory of Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

A new prenylated indole alkaloid 11,17-epi-mangrovamide A(1),a new natural occurring product,1,7-dihydroxy-6-methyl-8-hydroxymethyl-xanthone(2),two known alkaloids,mangrovamide A(3)and mangrovamide G(4),and four known polyketide derivatives(5–8)were isolated and identified from the cold-seep sediment derived fungal strain Talaromyces funiculosus *** structures were elucidated by combination of nuclear magnetic resonance(NMR),high resolution electrospray ionization mass spectroscopy(HRESIMS),quantum chemical electronic circular dichroism(ECD),and DP4+probability analysis as well as by comparison of the data with literature *** isolated compounds were tested for antibacterial activities.

关键词： Talaromyces funiculosus cold seep prenylated indole alkaloid antimicrobial activity

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A Lightweight Edge Network Intrusion Detection System Based on MobileVit 10th

A Lightweight Edge Network Intrusion Detection System Based ...

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10th International Conference of Pioneering Computer Scientists, Engineers and Educators, ICPCSEE 2024

作者： Yang, Xiaobo Hu, Xiaobo Li, Chao Zhou, Lin Wang, Yong School of Computer Science and Technology Shanghai University of Electric Power Shanghai China State Grid Key Laboratory of Power Industrial Chip Design and Analysis Technology Beijing Smart-Chip Microelectronics Technology Co. Ltd. Beijing China State Grid Digital Technology Holding Co. Beijing China

ISBN: (纸本)9789819787487

Aiming at the current problems of limited computational and storage resources in edge networks, poor robustness of traditional machine learning algorithms, and the large resource overhead required to deploy deep learning algorithms to edge networks, we proposes a lightweight intrusion detection system based on MobileViT, which can detect cyber-attack traffic in edge networks with little resource consumption. The system uses smote to balance the dataset to make the detection model more sensitive to a small number of samples, and then transforms the network traffic into a custom grey scale graph, which reduces the time of transformation and improves the accuracy of the model, which is then fed into a modified minor-MobileViT network for training, and then tested in a test set. Experimental results with relatively few model parameters show that our proposed method has good detection performance, while the model requires less storage space and has low computational overhead, making it suitable for network traffic detection and classification under edge networks. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.

关键词： Network intrusion

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Two-time Calibration at Both Ends for Sulfur Measurement by Using High Frequency Induction Infrared Absorption Method 9

Two-time Calibration at Both Ends for Sulfur Measurement by ...

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9th Annual International Conference on Material science and Environmental Engineering, MSEE 2021

作者： Wei, Jianhuan AECC Beijing Institute of Aeronautical Materials Beijing Key Laboratory of Aeronautical Materials Testing and Evaluation Aviation Key Laboratory of science and Technology on Materials Testing and Evaluation China

High frequency induction heating infrared absorption method is a relative measurement method, and it requires calibrating the analyzer during the measurement process. Usually, one-time calibration on an analyzer is made for high sulfur value by using standard substances. The method proposed by this paper calibrates carbon-sulfur analyzers with a method of two-time calibration at both ends, which eliminates the impact of sulfur blank and thus improves the accuracy and precision of ultra-low sulfur measurement. The method extents the lower limit of measurement of sulfur in high temperature alloy, to 0.00005%, namely, 0.5ppm. © 2022 Institute of Physics Publishing. All rights reserved.

关键词： Calibration

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A New Emission Mode of PSR B1859+07

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Research in Astronomy and Astrophysics 2023年第10期23卷 176-183页

作者： Tao Wang P.F.Wang J.L.Han Yi Yan Ye-Zhao Yu Feifei Kou National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China The key Laboratory for Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Qiannan Normal University for Nationalities Duyun 558000China Xinjiang Astronomical Observatories Chinese Academy of SciencesUrumqi 830011China

Previous studies have identified two emission modes in PSR B1859+07: a normal mode that has three prominent components in the average profile, with the trailing one being the brightest, and an anomalous mode(i.e., the A mode) where emissions seem to be shifted to an earlier phase. Within the normal mode, further analysis has revealed the presence of two submodes, i.e., the cW mode and c B mode, where the central component can appear either weak or bright. As for the anomalous mode, a new bright component emerges in the advanced phase while the bright trailing component in the normal mode disappears. New observations of PSR B1859+07 using the Fivehundred-meter Aperture Spherical Radio Telescope(FAST) have revealed the existence of a previously unknown emission mode, dubbed the Af mode. In this mode, all emission components seen in the normal and anomalous modes are detected. Notably, the mean polarization profiles of both the A and Af modes exhibit a jump in the orthogonal polarization angle modesin the bright leading component. The polarization angles for the central component in the original normal mode follow two distinct orthogonal polarization modes in the A and Af modes respectively. The polarization angles for the trailing component show almost the same but a small systematic shift in the A and Af modes, roughly following the values for the c W and cB modes. Those polarization features of this newly detected emission mode imply that the anomalous mode A of PSR B1859+07 is not a result of “phase shift”or “swooshes” of normal components, but simply a result of the varying intensities of different profile ***, subpulse drifting has been detected in the leading component of the Af mode.

关键词： (stars:)pulsars:individual(PSR B1859+07) polarization plasmas

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Effects of aging on mechanical sensitivity threshold and thermal decomposition characteristic of RDX/HMX

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Defence technology(防务技术) 2025年第3期45卷 62-72页

作者： Shian Zhang Yanru Wang Zeshan Wang Deyun Liu Mingkun Fang Zhiyong Ma Xingliang Wu Xibo Jiang Sen Xu Dabin Liu School of Chemistry and Chemical Engineering Nanjing University of Science and TechnologyNanjing 210094China China North Industries Group Corporation Beijing 100821China National Key Laboratory of Energetic Materials Xi'an 710000China China National Quality Inspection and Testing Center for Industrial Explosive Materials Nanjing 210094China

In order to analyze the influences of storage aging on the safety of typical elemental explosives,the aged cyclotrimethylene trinitramine(RDX)and cyclotetramethylene tetranitramine(HMX)were prepared by isothermal aging *** reaction thresholds of aged RDX and HMX under any ignition probability were studied by Langlie-Optimal D *** thermal decomposition characteristics of RDX and HMX after aging were analyzed by DSC and *** results showed that compared with unaged RDX and HMX,on the one hand,the critical impact energy and critical friction of RDX and HMX aged for 14,28,and 56 days are significantly reduced at an explosion probability of 50%,0.01%,and 0.0001%,*** the increase of aging time,the mechanical sensitivity of RDX and HMX increases *** the other hand,the initial decomposition temperature of RDX and HMX after 56 days of aging decreases,the decomposition heat decreases,the activation energy increases,and the reaction difficulty increases.

关键词： RDX HMX 71℃isothermal aging Langlie-optimal D method Mechanical sensitivity Thermal decomposition characteristic

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Two-dimensional localized modes in nonlinear systems with linear nonlocality and moiré lattices

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Frontiers of physics 2024年第4期19卷 265-273页

作者： Xiuye Liu Jianhua Zeng Center for Attosecond Science and Technology State Key Laboratory of Transient Optics and PhotonicsXi’an Institute of Optics and Precision Mechanics of Chinese Academy of SciencesXi’an 710119China University of Chinese Academy of Sciences Beijing 100049China Collaborative lnnovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

Periodic structures structured as photonic crystals and optical lattices are fascinating for nonlinear waves engineering in the optics and ultracold atoms ***éphotonic and optical lattices—two-dimensional twisted patterns lie somewhere in between perfect periodic structures and aperiodic ones—are a new emerging investigative tool for studying nonlinear localized waves of diverse ***,a theory of two-dimensional spatial localization in nonlinear periodic systems with fractional-order diffraction(linear nonlocality)and moiréoptical lattices is ***,the flat-band feature is well preserved in shallow moiréoptical lattices which,interact with the defocusing nonlinearity of the media,can support fundamental gap solitons,bound states composed of several fundamental solitons,and topological states(gap vortices)with vortex charge s=1 and 2,all populated inside the finite gaps of the linear Bloch-wave *** the linear-stability analysis and direct perturbed simulations,the stability and instability properties of all the localized gap modes are surveyed,highlighting a wide stability region within the first gap and a limited one(to the central part)for the third *** findings enable insightful studies of highly localized gap modes in linear nonlocality(fractional)physical systems with shallow moirépatterns that exhibit extremely flat bands.

关键词： moiréoptical lattices gap solitons and vortices ultracold atoms Gross-Pitaevskii/nonlinear fractional Schrödinger equation nonlinear fractional systems

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Temperature-dependent compression properties and failure mechanisms of ZrNiSn-based half-Heusler thermoelectric compounds

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Journal of Materials science & technology 2024年第26期193卷 29-36页

作者： Yanyan Lu Pengxin Zhang Jinsong Wang Qingfeng Song Zhanhui Chen Yali Wang Lidong Chen Shengqiang Bai Wenzhi Wang School of Aeronautics Northwestern Polytechnical UniversityXi’anShaanxi 710072China State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China School of Aviation Beijing Institute of TechnologyZhuhaiGuangdong 519088China Analytical and Testing Center Northwestern Polytechnical UniversityXi’anShaanxi 710072China

Half-Heusler(HH)compounds have emerged as promising candidates for high-temperature thermoelectric power generation;however,their mechanical properties in service environments have been scarcely *** this study,the temperature dependences of the mechanical responses and failure mechanisms of an n-type ZrNiSn-based HH compound(Zr_(0.5)Hf_(0.5)NiSn_(0.985)Sb_(0.015))were systematically evaluated through high-temperature compression tests and microfractographic *** test results indicated that the elastic modulus and ultimate compressive strength of Zr_(0.5)Hf_(0.5)NiSn_(0.985)Sb_(0.015)decreased with increasing *** stress-strain behavior of the material changed from linear(300,500,and 700 K)to nonlinear(900 and 1100 K).Microfractography observations revealed that increasing the temperature reduced the strength of the grain boundary as well as aggravated oxidation and segregation on the fracture surface,which significantly impacted the macro-compressive behavior of Zr_(0.5)Hf_(0.5)NiSn_(0.985)Sb_(0.015)at elevated ***,a stress-strain relationship for the ZrNiSnbased HH was proposed to describe the change in the compressive response from linear to nonlinear with increasing *** present study elucidates the load-carrying and failure mechanisms of Zr_(0.5)Hf_(0.5)NiSn_(0.985)Sb_(0.015)within its operational temperature range,providing valuable guidance for the mechanical design of HH thermoelectric devices over their entire service temperature range.

关键词： Half-Heusler compounds Temperature dependence Mechanical response Failure mechanism

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A novel photocatalytic mechanism of volatile organic compounds degradation on BaTiO_(3)under visible light:Photo-electrons transfer from photocatalyst to pollutant

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Chinese Chemical Letters 2025年第3期36卷 182-187页

作者： Teng Wang Jiachun Cao Juan Li Didi Li Zhimin Ao Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlKey Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of EducationInstitute of Environmental Health and Pollution ControlSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China Advanced Interdisciplinary Institute of Environment and Ecology Guangdong Provincial Key Laboratory of Wastewater Information Analysis and Early WarningBeijing Normal UniversityZhuhai 519087China

Wide bandgap semiconductors are typically activated under ultraviolet(UV)light irradiation for volatile organic compounds(VOCs)***,our previous study discovered that certain VOCs can interact with some wide bandgap semiconductors,formatting an intermediate bandgap between the VOCs and the conduction band of wide bandgap semiconductor,thus inducing visible light activation of the system,and photo-generated electrons are excited by visible light and transferred from the VOCs to the conduction band of *** this work,BaTiO_(3),traditionally is not active under visible light irradiation,however showed degradation rates of 100%and 20%for styrene and toluene under visible light,*** functional theory(DFT)calculations indicate that the adsorption of styrene or toluene on the BaTiO_(3)surface reduces its bandgap from 2.93 eV to 1.36 eV and 2.26 eV,*** intermediate bandgap in this system is primarily formed by the valence band of BaTiO_(3)and the VOCs,and indicating that photo-generated electrons directly transfer from BaTiO_(3)to the VOCs under visible light,inducing degradation reactions of VOCs,i.e.,this work discovered a new transfer pathway of photo-electrons direct from the valence band of BaTiO_(3)to VOCs,while photo-electrons are from VOCs to the conductive band of wide-bandgap semiconductors in our previous work.

关键词： Volatile organic compounds Photocatalytic Degradation Wide-bandgap semiconductors Density functional theory Degradation mechanism

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Age and fluid source constraints of the Haoyaoerhudong orogenic gold deposit,North China:Evidence from geochronology and noble gas isotopes

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Geoscience Frontiers 2024年第4期15卷 176-195页

作者： Chenglong Fan Jingwen Mao Huishou Ye Yitian Wang Junchen Liu Wei Jian Xuyang Meng Wenhao Tang Weiwei Chao Peng Wang School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China MNR Key Laboratory for Exploration Theory&Technology of Critical Mineral Resources China University of GeosciencesBeijing 100083China Ministry of Natural Resources(MNR)Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Efficient Utilization of Resources by the Province and Ministry Guilin University of TechnologyGuilin 541004China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013JiangxiChina School of Earth Sciences and Spatial Information Engineering Hunan University of Science and TechnologyXiangtan 411201China

The Haoyaoerhudong gold deposit,located in the northwestern part of the North China craton(NCC),has produced over 120 metric tonnes(t)of gold since *** has a total reserve of>240 t at average gold grade of 0.62 g/t,making it one of the largest open pit gold mines in *** steeply dipping,large-tonnage,low-grade,vein-or veinlet-type gold orebodies are hosted in strongly-deformed Mesoproterozoic carbonaceous schist of the Bayan Obo *** laminated/boudinaged veins/veinlets in the sinistral ductile-brittle shear zones are dominated by quartz,biotite,gold-bearing löllingite,pyr-rhotite,(arseno)pyrite,with minor native gold,titanite and *** this paper,we present new in situ U-Pb geochronological data on magmatic zircon from the preore dikes,on metamorphic and hydrothermal xenotime,and on hydrothermal titanite from the hydrothermally altered carbonaceous schist and auriferous quartzsulfides veins/veinlets,as well as He-Ar isotopic analysis on gold-bearing(arseno)pyrite in the syn-ore *** metamorphic xenotime U-Pb age of 426±6.0 Ma(2σ)records a regional metamorphic event,possibly related to the accretion of the Bainaimiao arc onto the *** pre-ore andesitic dikes yielded similar emplacement ages at~278 Ma constrained by laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)U-Pb zircon *** xenotime grains from the altered carbonaceous schist and auriferous quartz-sulfides veins yielded U-Pb ages of 256.0±4.1 Ma(2σ)and 254.4±2.1 Ma(2σ),respectively,overlapping with that of the hydrothermal titanite at 255.4±0.8 Ma(2σ)from the laminated quartz-sulfides *** indicates that the gold mineralization occurred at ca.255 ***~255 Ma gold mineralization age is much younger than the previously reported Early-Middle Permian regional magmatic activity(ca.291 Ma to 268 Ma),and may be associated with the regional sinistral strike-slip event in the late orogenic cycle related to the collision between the Siberian craton

关键词： Xenotime Titanite In situ U-Pb dating Noble gas Orogenic gold deposit North China Craton

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