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Chinese Physics b 2016年第5期25卷 429-433页

作者： A Kumaresh R Arun Kumar N Ravikumar U madhusoodanan b S Panigrahi K marimuthu m Anuradha GRD Centre for materials Research PSG College of TechnologyCoimbatoreIndia Department of Physics PSG College of TechnologyCoimbatoreIndia Radiation Safety Division Indira Gandhi Centre for Atomic ResearchKalpakkamIndia Department of Physics Gandhigram Rural UniversityDindigulIndia PSG Institute of Advanced Studies CoimbatoreIndia

Rare earth europium（Eu（3＋））-doped lithium tetraborate（Eu：Li_2b_4O_7） crystal is grown from its stoichiometric melt by microtube Czochralski pulling technique（μT-Cz） for the first time. The grown crystals are subjected to powder x-ray diffraction（PXRD） analysis which reveals the tetragonal crystal structure of the crystals. UV–vis–NIR spectral analysis is carried out to study the optical characteristics of the grown crystals. The crystal is transparent in the entire visible region, and the lower cutoff is observed to be at 304 nm. The existence of bO_3 and bO_4 bonding structure and the molecular associations are analyzed by Fourier transform infrared（FTIR） spectroscopy. The results of excitation and emission-photoluminescence spectra of europium ion incorporated in lithium tetraborate（LTb） single crystal reveal that the observations of peaks at 258,297, and 318 nm in the excitation spectra and peaks at 579, 591, 597, 613, and 651 nm are observed in the emission *** chromaticity coordinates are calculated from the emission spectra, and the emission intensity of the grown crystal is characterized through a CIE 1931（Commission International d＇Eclairage） color chromaticity diagram.

关键词： crystal growth optical material growth from melt photoluminescence study

LHAASO detection of very-high-energy γ-ray emission surrounding PSR J0248+6021

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Science China(Physics,mechanics & Astronomy) 2025年

作者： Zhen Cao F.Aharonian Axikegu Y.X.bai Y.W.bao D.bastieri X.J.bi Y.J.bi W.bian A.V.bukevich Q.Cao W.Y.Cao Zhe Cao J.Chang J.F.Chang A.m.Chen E.S.Chen H.X.Chen Liang Chen Lin Chen Long Chen m.J.Chen m.L.Chen Q.H.Chen S.Chen S.H.Chen S.Z.Chen T.L.Chen Y.Chen N.Cheng Y.D.Cheng m.C.Chu m.Y.Cui S.W.Cui X.H.Cui Y.D.Cui b.Z.Dai H.L.Dai Z.G.Dai Danzengluobu X.Q.Dong K.K.Duan J.H.Fan Y.Z.Fan J.Fang J.H.Fang K.Fang C.F.Feng H.Feng L.Feng S.H.Feng X.T.Feng Y.Feng Y.L.Feng S.Gabici b.Gao C.D.Gao Q.Gao W.Gao W.K.Gao m.m.Ge T.T.Ge L.S.Geng G.Giacinti G.H.Gong Q.b.Gou m.H.Gu F.L.Guo J.Guo X.L.Guo Y.Q.Guo Y.Y.Guo Y.A.Han O.A.Hannuksela m.Hasan H.H.He H.N.He J.Y.He Y.He Y.K.Hor b.W.Hou C.Hou X.Hou H.b.Hu Q.Hu S.C.Hu C.Huang D.H.Huang T.Q.Huang W.J.Huang X.T.Huang X.Y.Huang Y.Huang Y.Y.Huang X.L.Ji H.Y.Jia K.Jia H.b.Jiang K.Jiang X.W.Jiang Z.J.Jiang m.Jin m.m.Kang I.Karpikov D.Khangulyan D.Kuleshov K.Kurinov b.b.Li C.m.Li Cheng Li Cong Li D.Li F.Li H.b.Li H.C.Li Jian Li Jie Li K.Li S.D.Li W.L.Li W.L.Li X.R.Li Xin Li Y.Z.Li Zhe Li Zhuo Li E.W.Liang Y.F.Liang S.J.Lin b.Liu C.Liu D.Liu D.b.Liu H.Liu H.D.Liu J.Liu J.L.Liu m.Y.Liu R.Y.Liu S.m.Liu W.Liu Y.Liu Y.N.Liu Q.Luo Y.Luo H.K.Lv b.Q.ma L.L.ma X.H.ma J.R.mao Z.min W.mitthumsiri H.J.mu Y.C.Nan A.Neronov K.C.Y.Ng L.J.Ou P.Pattarakijwanich Z.Y.Pei J.C.Qi m.Y.Qi b.Q.Qiao J.J.Qin A.Raza D.Ruffolo A.Sáiz m.Saeed D.Semikoz L.Shao O.Shchegolev X.D.Sheng F.W.Shu H.C.Song Yu.V.Stenkin V.Stepanov Y.Su D.X.Sun Q.N.Sun X.N.Sun Z.b.Sun J.Takata P.H.T.Tam Q.W.Tang R.Tang Z.b.Tang W.W.Tian L.H.Wan C.Wang C.b.Wang G.W.Wang H.G.Wang H.H.Wang J.C.Wang Kai Wang Kai Wang L.P.Wang L.Y.Wang P.H.Wang R.Wang W.Wang X.G.Wang X.Y.Wang Y.Wang Y.D.Wang Y.J.Wang Z.H.Wang Z.X.Wang Zhen Wang Zheng Wang D.m.Wei J.J.Wei Y.J.Wei T.Wen C.Y.Wu H.R.Wu Q.W.Wu S.Wu X.F.Wu Y.S.Wu S.Q.Xi J.Xia G.m.Xiang D.X.Xiao G.Xiao Y.L.Xin Y.Xing D.R.Xiong Z.Xiong D.L.Xu R.F.Xu R.X.Xu W.L.Xu L.Xue D.H.Yan J.Z.Yan T.Yan C.W.Yang C.Y.Yang F.Yang F.F.Yang L.L.Yang m.J.Yang R.Z.Yang W.X.Yang Y.H.Yao Z.G.Yao L.Q.Yin N.Yin X.H.You Z.Y.You Y.H Southwest Jiaotong University School of Astronomy and Space Science Nanjing University Center for Astrophysics Guangzhou University Tsung-Dao Lee Institute & School of Physics and Astronomy Shanghai Jiao Tong University Institute for Nuclear Research of Russian Academy of Sciences Hebei Normal University University of Science and Technology of China LHAASO Collaboration State Key Laboratory of Particle Detection and Electronics Key Laboratory of Dark matter and Space Astronomy & Key Laboratory of Radio Astronomy Purple mountain Observatory Chinese Academy of Sciences Research Center for Astronomical Computing Zhejiang Laboratory Key Laboratory for Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physics and Astronomy Key Laboratory of Particle Astrophysics & Experimental Physics Division & Computing Center Yunnan University Key Laboratory of Cosmic Rays (Tibet University) ministry of Education Department of Physics The Chinese University of Hong Kong Key Laboratory of Radio Astronomy and Technology National Astronomical Observatories Chinese Academy of Sciences School of Physics and Astronomy (Zhuhai) & School of Physics (Guangzhou) & Sino-French Institute of Nuclear Engineering and Technology (Zhuhai) Sun Yat-sen University Institute of High Energy Physics Institute of Frontier and Interdisciplinary Science Shandong University APC Université Paris Cité CNRS/IN2P3 CEA/IRFU Observatoire de Paris Department of Engineering Physics & Department of Astronomy Tsinghua University School of Physics and microelectronics Chinese Academy of Sciences Zhengzhou University Yunnan Observatories Chinese Academy of Sciences China Center of Advanced Science and Technology College of Physics Sichuan University School of Physics Peking University Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and Technology University of Chinese Academy of Sciences Guangxi University Department of Physics Faculty of Science mahidol University moscow Institute

We report the detection of an extended very-high-energy(VHE) γ-ray source coincident with the location of middle-aged(62.4 kyr) pulsar PSR J0248+6021, by using the LHAASO-WCDA data of live 796 d and LHAASO-Km2A data of live 1216d. A significant excess of γ-ray induced showers is observed both by WCDA in energy bands of 1-25 Te V and Km2A in energy bands of >25 TeV with 7.3σ and 13.5σ, respectively. The best-fit position derived through WCDA data is R.A. = 42.06°± 0.12°and Dec. = 60.24°± 0.13°with an extension of 0.69°±0.15°and that of the Km2A data is R.A.= 42.29°± 0.13°and Dec. =60.38°± 0.07°with an extension of 0.37°±0.07°. No clear extended multiwavelength counterpart of this LHAASO source has been found from the radio band to the GeV band. The most plausible explanation of the VHE γ-ray emission is the inverse Compton process of highly relativistic electrons and positrons injected by the pulsar. These electrons/positrons are hypothesized to be either confined within the pulsar wind nebula or to have already escaped into the interstellar medium, forming a pulsar halo.

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Observation of the γ-ray emission from W43 with LHAASO

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Science China(Physics,mechanics & Astronomy) 2025年

In this paper, we report the detection of the very-high-energy (VHE, 100 Ge V100 TeV) γ-ray emissions from the direction of the young star-forming region W43, observed by the Large High Altitude Air Shower Observation (LHAASO). The extended γ-ray source was detected with a significance of～16σby Km2A and～17σby WCDA, respectively. The angular extension of this γ-ray source is about 0.5 degrees, corresponding to a physical size of about 50pc. We discuss the origin of the γ-ray emission and possible cosmic ray acceleration in the W43 region using multi-wavelength data. Our findings suggest that W43 is likely another young star cluster capable of accelerating cosmic rays (CRs) to at least several hundred TeV.

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Strong and ductile mg alloys developed by dislocation engineering

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Journal of materials Science & Technology 2019年第3期35卷 394-395页

作者： m.Wang b.b.He m.X.Huang Department of mechanical Engineering The University of Hong Kong Shenzhen Institute of Research and Innovation The University of Hong Kong

Dislocation engineering concept has been successfully employed to tackle the strength-ductility trade-off in steels, resulting in the development of high-strength high-ductility deformed and partitioned(D&P)steel. The present perspective proposes to employ such dislocation engineering concept to develop strong and ductile magnesium(mg) alloys. High density of dislocations could be generated at appropriate temperature and retained in the mg alloy after quenching to room temperature. Those dislocations inherited from the warm deformation could provide dislocation sources when the mg alloy is deformed at room temperature, resulting in good ductility. The high dislocation density generated at warm deformation provides dislocation forest hardening, leading to improved yield strength of mg alloy.

关键词： Dislocation engineering mg alloys Warm rolling Strength and ductility

Nonlinear continuous bi-inductance electrical line with dissipative elements:Dynamics of the low frequency modulated waves

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Chinese Physics b 2020年第4期29卷 179-189页

作者： S m Ngounou F b Pelap Unite de Recherche de mecanique et de modelisation des Systèmes Physiques(UR-2 mSP) Faculte des SciencesUniversite de DschangBP 69 DschangCameroun Unite de Recherche de matiere Condensee d'Electronique et de Traitement du Signal(UR-mACETS) Faculte des SciencesUniversite de DschangBP 67 DschangCameroun

The dynamics of modulated waves in a nonlinear bi-inductance transmission line with dissipative elements are *** show the existence of two frequency modes and carry out intensive investigations on the low frequency *** to the multiple scales method,the behavior of these waves is investigated and the dissipative effects are *** appears that the dissipation coefficient increases with the carrier wave *** the continuous approximation,we derive that the propagation of these waves is governed by the complex Ginzburg-Landau equation instead of the Korteweg-de-Vries equation as previously *** studies of the dynamics of plane waves in the line reveal the existence of three additional regions in the dispersion curve where the modulational phenomenon is *** the low frequency mode,we demonstrate that the network allows the propagation of dark and bright *** findings are in perfect agreement with the analytical predictions.

关键词： dissipative bi-inductance network low frequency mode continuous approximation complex Ginzburg-Landau equation

Seepage properties of a single rock fracture subjected to triaxial stresses

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Progress in Natural Science:materials International 2007年第12期17卷 1482-1486页

作者： m b Jaksa 5005 Australia School of Civil and Environmental Engineering University of Adelaide

Coupled properties of seepage and stress fields of rock fractures greatly influence the safety of geotechnical engineering work. based on the closing deformation principle of a single rock fracture, equations describing relationships of aperture and triaxial stresses are developed, and coupled models of seepage and triaxial stresses are proposed. Seepage tests are conducted under triaxial stress conditions by adopting hard granite specimens with an artificial fracture. The results show that the normal stress, lateral stress and seepage pressure significantly affect the flow behavior of rock fractures, and that hydraulic conductivity decreases with increasing normal stress, but increases with rising lateral stress or seepage pressure. In addition, an exponential function provides a good representation of the seepage characteristics of a single rock fracture subjected to triaxial stresses.

关键词： triaxial stresses rock fractures seepage hydraulic conductivity coupling model.

Dynamics of high-frequency modulated waves in a nonlinear dissipative continuous bi-inductance network

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Chinese Physics b 2021年第6期30卷 193-205页

作者： S m Ngounou F b Pelap Unitéde Recherche de mécanique et de modélisation des Systèmes Physiques(UR-2 mSP) Facultédes SciencesUniversitéde DschangBP 69 DschangCameroun Unitéde Recherche de matière Condensée d'Electronique et de Traitement du Signal(UR-mACETS) Facultédes SciencesUniversitéde DschangBP 67 DschangCameroun

This paper presents intensive investigation of dynamics of high frequency nonlinear modulated excitations in a damped bimodal lattice. The effects of the dissipation are considered through a linear dissipation coefficient whose evolution in terms of the carrier wave frequency is checked. There appears that the dissipation coefficient increases with the carrier wave frequency. In the linear limit and for high frequency waves, study of the asymptotic behavior of plane waves reveals the existence of two additional regions in the dispersion curve where the modulational phenomenon is observed compared to the lossless line. based on the multiple scales method exploited in the continuum approximation using an appropriate decoupling ansatz for the voltage of the two different cells, it appears that the motion of modulated waves is described by a dissipative complex Ginzburg–Landau equation instead of a Korteweg–de Vries equation. We also show that this amplitude wave equation admits envelope and hole solitons in the high frequency mode. From basic sources, we design a programmable electronic generator of complex signals with desired characteristics, which delivers signals exploited as input waves for all our numerical simulations. These simulations are performed in the LTspice software that uses realistic components and give the results that corroborate perfectly our analytical predictions.

关键词： dissipative bi-inductance network high-frequency mode continuous approximation dissipative complex Ginzburg–Landau equation programmable electronic generator LT-Pspice observations

A review of research on spontaneous combustion of coal

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International Journal of mining Science and Technology 2020年第3期30卷 303-311页

作者： m.Onifade b.Genc Department for management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam The School of mining Engineering University of the WitwatersrandSouth Africa

Coal oxidation at low temperatures is the heat source liable for the self-heating and spontaneous combustion of coal. This phenomenon has imposed severe problems in coal related industries. Attempts to understand this phenomenon by previous researchers have provided significant progress. It is wellknown that coal oxidation at low temperatures involves oxygen consumption and formation of gaseous and solid oxidation products. This process is majorly influenced by temperature, oxidation history of coal,coal properties, particle size distribution of the coal, etc. The current understanding of the phenomenon of self-heating and spontaneous combustion of coal is discussed along with the different experimental and numerical models established to predict self-heating characteristics of coal. This paper focuses on the global position of the study carried out by academics, research institutes and industries on spontaneous combustion of coal and coal mine fires. Within this framework, the generally used spontaneous combustion techniques to predict the spontaneous combustion liability of coal were evaluated. These techniques are well-known in their usage, but no specific method has become a standard to predict the spontaneous combustion liability. Further study is still needed to indicate a number of impending issues and to obtain a more complete understanding on the phenomenon.

关键词： Coalfields Experimental Numerical Propensity Self-heat Statistical method

Lateral load performance and seismic demand of unbonded scrap tire rubber pad base isolators

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 803-821页

作者： m.b.Zisan A.Igarashi Department of Urban management Kyoto UniversityKyoto 615-8540Japan Disaster Prevention Research Institute Kyoto UniversityKyoto 611-0011Japan

The scrap tire rubber pad(STRP)made by natural or synthetic rubber and high strength reinforcing cords exhibits substantial vertical stiffness and horizontal flexibility,and these properties can be regarded as suitable for seismic isolators for *** use of environmentally burdensome scrap tires as STRP isolators might be convenient as an efficient and low-cost solution for the implementation of aseismic design philosophy for low-to-medium rise buildings,especially in developing *** element analyses of unbonded square and strip-shaped STRP isolators subjected to a combination of axial and lateral loads are conducted to investigate its lateral deformation performance under seismic *** rubber of the isolator is modelled with mooney-Rivlin hyperelastic and Prony viscoelastic materials,including the mullins material damage *** influence of the length-to-width ratio and bearing height on the isolator performance is assessed in terms of the force-displacement relationship,horizontal stiffness,damping,and isolation *** is shown that the dependence of stiffness on the length-to-width ratio is significant in the longitudinal direction and minor in the transverse *** STRP isolators following the proposed design criteria are shown to satisfy the performance requirement at different levels of seismic demand specified by the ASCE/SEI 7-2010 seismic provisions.

关键词： lateral load STRP isolator length-to-width ratio height unbonded application performance-based design FEm

System size dependence in backward relativistic hadron production in pA and AA collisions

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Chinese Physics C 2014年第11期38卷 22-28页

作者： b.m.badawy Reactor Physics Department Nuclear Research Center Atomic Energy Authority Cairo Egypt

Abstract： In this comprehensive study the multiplicity characteristics of the backward emitted relativistic hadron （shower particle） through hadron-nucleus and nucleus-nucleus are overviewed in three dimensions. These dimensions are the projectile size, target size, and energy. To confirm the universality in this production system, wide ranges of system size and energy （Elab～2.1 A up to 200 A GeV） are used. The multiplicity characteristics of this hadron imply a limiting behavior with respect to the projectile size and energy. The target size is the main effective parameter in this production system. The exponential decay shapes is a characteristic feature of the backward shower particle multiplicity distributions. The decay constant changes with the target size to be nearly 2.02, 1.41, and 1.12 for the interactions with CNO, Era, and Agbr nuclei, respectively, irrespective of the projectile size and energy. While the backward production probability and average multiplicity are constants at different projectile sizes and energies, they can be correlated with the target size in power law relations.

关键词： backward relativistic hadron dubna energy and SPS energy multiplicity characteristics system size,nuclear limiting fragmentation