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The Bright Single Pulse Emission from PSR B1133+16

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Research in Astronomy and Astrophysics 2024年第4期24卷 253-261页

作者： Jun Tan Zhi-Gang Wen Zhen Wang Xue-Feng Duan Hong-Guang Wang Na Wang Vishal Gajjar Jian-Ping Yuan Rai Yuen Wen-Ming Yan Jian-ling Chen Wei Han hui Wang Cheng-Bing l.u Ai-Jun Dong Maths and Information Technology School Yuncheng UniversityYuncheng 044000China Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China Xinjiang Key laboratory of Radio Astrophysics Urumqi 830011China School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Space Science laboratory University of CaliforniaBerkeley 94710USA Department of Physics and Electronic Engineering Yuncheng UniversityYuncheng 044000China School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China

We have conducted a comprehensive investigation into the bright single pulse emission from PSR B1133+16using the Giant Metrewave Radio *** time resolution data(61μs)were obtained at a center frequency of 322 MHz with a bandwidth of 32 MHz over a continuous observation period of 7.45 hr.A total of 1082 bright pulses were sporadically detected with peak flux densities ranging from 10 to 23 times stronger than the average pulse ***,no giant pulse-like emission with a relative pulse energy larger than 10 and extremely short duration was detected,indicating that these bright pulses cannot be categorized as giant pulse *** majority of these bright pulses are concentrated in pulse phases at both the leading and trailing windows of the average pulse profile,with an occurrence ratio of approximately *** pulse energy distribution for all individual pulses can be described by a combination of two Gaussian components and a cutoff power-law with an index of α=-*** updated nulling fraction of 15.35%±0.45% was determined from the energy *** emission of individual pulses follows a log-normal distribution in peak flux density *** is imperative that regular phase drifting in bright pulse sequence is identified in both the leading and trailing components for the first *** physical mechanisms are discussed in detail to provide insights into these observations.

关键词： (stars:)pulsars:general (stars:)pulsars:individual(PSR B1133+16) methods:observational methods:data analysis

label-Aware Chinese Event Detection with Heterogeneous Graph Attention Network

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Journal of Computer Science & Technology 2024年第1期39卷 227-242页

作者：崔诗尧郁博文从鑫柳厅文谭庆丰时金桥 Institute of Information Engineering Chinese Academy of SciencesBeijing 100190China School of Cyber Security University of Chinese Academy of SciencesBeijing 100049China Cyberspace Institute of Advanced Technology Guangzhou UniversityGuangzhou 510006China School of Cyber Security Beijing University of Posts and TelecommunicationsBeijing 100088China

Event detection(ED)seeks to recognize event triggers and classify them into the predefined event *** ED is formulated as a character-level task owing to the uncertain word *** methods try to incorpo-rate word-level information into characters to enhance their ***,they experience two ***,they fail to incorporate word-level information into each character the word encompasses,causing the insufficient word-charac-ter interaction ***,they struggle to distinguish events of similar types with limited annotated instances,which is called the event confusing *** paper proposes a novel model named label-Aware Heterogeneous Graph Attention Network(l-HGAT)to address these two ***,we first build a heterogeneous graph of two node types and three edge types to maximally preserve word-character interactions,and then deploy a heterogeneous graph attention network to enhance the semantic propagation between characters and ***,we design a pushing-away game to enlarge the predicting gap between the ground-truth event type and its confusing counterpart for each *** results show that our l-HGAT model consistently achieves superior performance over prior competitive methods.

关键词： Chinese event detection heterogeneous graph attention network(HGAT) label embedding

Protection of steel hooks embedded in glass-fiber-reinforced concrete against macrocell corrosion

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Petrol.um Research 2024年第2期9卷 317-326页

作者： Husnu Gerengi Muhammed Maraşlı Marziya Rizvi Beni Kohen Ismail Taşkıran Corrosion Research laboratory Department of Mechanical EngineeringDuzce University81620DuzceTurkey Department of Engineering and Applied Sciences University of BergamoBGItaly Fibrobeton Company R&D Center DuzceTurkey Department of Chemistry Babasaheb Bhimrao Ambedkar UniversityLucknow226003U.PIndia

This study evaluated the corrosion behavior of steel hooks embedded in GFRC,which were protected by a zinc-rich(96%Zn)galvanizing *** coating provided the hooks with active cathodic protection and a passive physical *** corrosion may form when the anode is smaller than the total steel ***,the steel hooks at the embedment juncture were additionally sealed against water ingress and air exchange using a construction *** study was conducted in three phases in a salt-spray ***,the electrogalvanized steel hooks embedded in GFRC were allowed to freely corrode for 7 *** the second phase,the electrogalvanized steel hooks were painted with the zinc-rich coating and observed over 7 *** the third phase,the steel hooks were protected by the zinc-rich coating together with a primer and construction sealant,and observed over 7 *** evaluate the electrogalvanized hooks and the corrosion products formed,the thickness of the material was *** on the metal surface was inferred by studying the surface morphology of the hooks at various points of contact and after different periods of time.

关键词： Steel rebars Concrete corrosion GFRC Galvanization Sealant

Radiation Spectral Analysis of 3D Dust Molecular Clusters(PAHs)and Peptoids under Ionization and Electric Field in ISM

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Research in Astronomy and Astrophysics 2024年第1期24卷 70-77页

作者： Ruiqing Wu Chunhua Zhu Guoliang lü Xiaojiao Zhang Xizhen lu Jinlong Yu Wujin Chen Mengqiu long School of Physics and Electronics Central South UniversityChangsha 410083China School of Physical Science and Technology Xinjiang UniversityUrumqi 830046China School of Microelectronics and Physics Hunan University of Technology and BusinessChangsha 410205China College of Mechanical and Electronic Engineering Tarim UniversityAlar 843300China School of Medicine Xinjiang Medical UniversityUrumqi 830011China

Polycyclic aromatic hydrocarbons(PAHs),PANHs,and peptoids dust spectral cal.ulations from the interstellar medium(ISM)are important for dust observations and *** goal is to cal.ulate the radiation spectrum of spherical PAHs dust clusters in a vacuum containing ionized and applied in the presence of an electric *** propose a new simple computational model to cal.ulate the size of three-dimensional spherical dust clusters formed by different initial dust *** the Vienna Ab-initio Simulation Package code,the density functional theory with the generalized approximation was used to cal.ulate the electron density gradient and obtain the radiation spectrum of *** the radius of spherical dust clusters is~[0.009-0.042]μm,the dust radiation spectrum agrees well with the Z=0.02 mMMP stellar spectra,and the PAHs radiation spectrum of NGC 4676 at wavelengths of(0-5]μm and(5-10]μm,*** the ionized state,the N-PAH,C_(10)H_(9)N,2(C_(4)H_(4))^(1+),and peptoids 4(CHON),(C_(8)H_(10)N_(2)O_(5))^(1+)dust clusters at 3.3μm,while the 2(C_(22)H_(21)N_(3)O_(2))^(1+),4(CHON)dust clusters at 5.2μm have obvious *** is a characteristic of part of PAHs and peptoids clusters radiation at the nearinfrared wavelength of 2μ***,especially after applying an electric field to the dust,the emission spectrum of the dust increases significantly in the radiation wavelength range[3-10]μ***,the dust clusters of PAHs,PANHs,and peptoids of the radius size~[0.009-0.042]μm are likely to exist in the ISM.

关键词： ISM:structure ISM:molecules radiation mechanisms:general (ISM:)dust extinction

Pumping-induced Well Hydraulics and Groundwater Budget in a leaky Aquifer System with Vertical Heterogeneity in Aquitard Hydraulic Properties

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 477-490页

作者： ZHuANG Chao lÜChenyang YAN long lI Yabing ZHOu Zhifang WANG Jinguo DOu Zhi Walter A.IllMAN School of Earth Sciences and Engineering Hohai UniversityNanjing 211100China School of Geography Earth and Environmental SciencesUniversity of BirminghamBirmingham B152TTU.K. Department of Modern Mechanics University of Science and Technology of ChinaHefei 230027China Department of Earth and Environmental Sciences University of WaterlooOntario N2L 3G1Canada

In groundwater hydrology,aquitard heterogeneity is often less considered compared to aquifers,despite its significant impact on groundwater hydraulics and groundwater resources evaluation.A semi-analytical solution is derived for pumping-induced well hydraulics and groundwater budget with consideration of vertical heterogeneity in aquitard hydraulic conductivity(K)and specific storage(S_(s)).The proposed new solution is innovative in its partitioning of the aquitard into multiple homogeneous sub-layers to enable consideration of various forms of vertically heterogeneous K or S_(s).Two scenarios of analytical investigations are explored:one is the presence of aquitard interlayers with distinct K or S_(s) values,a common field-scale occurrence;another is an exponentially depth-decaying aquitard S_(s),a regional-scale phenomenon supported by statistical *** investigations reveal that a low-K interlayer can significantly increase aquifer drawdown and enhance aquifer/aquitard depletion;a high-S_(s) interlayer can noticeably reduce aquifer drawdown and increase aquitard *** of low-K or high-S_(s) interlayers also significantly impact well hydraulics and groundwater *** the context of an exponentially depth-decaying aquitard S_(s),a larger decay exponent can enhance aquifer *** using current models with a vertically homogeneous aquitard,half the sum of the geometric and harmonic means of exponentially depth-decaying aquitard S_(s) should be used to cal.ulate aquitard depletion and unconfined aquifer leakage.

关键词： hydrogeology aquitard vertical heterogeneity semi-analytical solution well hydraulics groundwater budget

Wear of semi-solid rheocast SiC_p/Al metal matrix composites

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中国有色金属学会会刊：英文版 2010年第S3期20卷 852-856页

作者： u.A.CuRlE l.IVANCHEV Materials Science and Manufacturing Council for Scientific and Industrial Research(South Africa)

Rheocasting of plates in Al alloy 359 reinforced with SiC at 11%,27% and 50%(volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIR-RCS) in rheo-processing and high pressure die casting of SiC metal matrix *** metal matrix consisting of nearly spherical proeutectic α(Al) globules was *** of fibrous eutectic silicon took place upon heat treatment of the as-cast metal matrix composites(MMCs).Hardness increases as the volume fractions of SiC *** rates of the MMCs in the F and T6 heat treatment conditions were assessed with a metallographic preparation *** is found that the 11% SiC MMC wear rate is higher on SiC abrasives compared with the 50% SiC MMC wear rate due to wear of the aluminum *** trend is reversed on diamond abrasives due to pull-out of the irregular shaped composite *** 50% SiC MMC suffers from composite particle fracture porosity after high pressure die casting(HPDC).

关键词： CSIR-RCS HPDC SiC F condition T6 condition wear rate hardness porosity

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S u Khan M l Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China university of Chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Surface Water Quality Profiling using Physicochemical Parameters in Open Defecation Free and Non-Open Defecation Free local Government Areas in Benue State, Nigeria

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Open Journal of Modern Hydrology 2024年第3期14卷 174-191页

作者： Moses T. Asoo Celestine u. Aguoru Innocent O. Ogbonna Hyacinth O.A. Oluma Benue State Ministry of Health Makurdi Nigeria Department of Plant Science and Biotechnology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria Department of Microbiology College of Biological Sciences Joseph Sarwuan Tarka University Makurdi Nigeria

Physicochemical parameters of surface water sources in the study of local government areas (lGAs) were assessed using standard procedures. The mean physicochemical parameters for pH (5.49), NO2 (0.23 mg/l), SO4 (0.77 mg/l), Na (28.72 mg/l), Ca (28.94 mg/l), Mg (17.50 mg/l), Cl (11.65 mg/l), TSS (6.27 mg/l), TDS (104.23 mg/l), boD (2.83 mg/l) and F (0.87 mg/l) were below WHO standards irrespective of their defecation status. The values for electrical conductivity (EC) (2770.50 µs/cm, turbidity (481.24 NTu), dissolved oxygen (DO) (5.32 mg/l), chemical oxygen demand (COD) (445.50 mg/l), K (125.06 mg/l), PO4 (0.78 mg/l) and Fe (0.57 mg/l) were above the WHO limits for safe water. Higher EC and COD values obtained in the study is evidence of pol.ution of the water sources by organic matter.

关键词： Open Defecation Surface Water Water Quality Standard Physicochemical Parameters

Effect of densification distribution on the Young's modulus of porous coatings after nano-indentation

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Acta Metal.urgica Sinica(English letters) 2012年第5期25卷 383-390页

作者： Xiaojuan l.u Ping XIAO Haiyan lI School of Environment Science and Engineering North China Electric Power University Yonghua North Street Baoding 071000 China School of Materials The University of Manchester Manchester M1 7HS UK School of Mechanical Aerospace and Civil Engineering The University of Manchester P.O. Box 88Sackville Street Manchester M60 1QD UK

Nano-indentation of a porous ceramic coating leads to crushing and densification of the coating under the indenter. In this work, finite element simulations of indentation on the porous coating have been carried out to study the effect of the size and dis- tribution of densification on Youngts modulus measured by nano-indentation. Two totally different distribution patterns have been simulated in this work. In the case of gradient densification, the Youngts modulus increased by 8.6% when the densifi- cation has occurred in the maximum influenced area. While the Young^s modulus increased by 2% with a uniformed densification. Examinations of the cross-section of the coatings have suggested that the densification after the indentation is close to the second model. The measured Young＇s modulus could have differed by 2%. The effect of densification on the Young＇s modulus measured by using nano-indentation is strongly dependent on the densification patterns of the porous coating.

关键词： Film Mechanical property Finite element simulation Porosity Electron Microscopy