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Measurement　of.Vibration　Derivative′s　Amplitude　and　Phase　by.Strobe　and　Optical　Phase　Shif.ing　Shearography

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Chinese Journal of.Lasers 1995年第2期B4卷 181-185页

作者： f. chen, y. y. hung, G. M. Brown(Department of.Mechanical Engineering, Oakland University.Rochester Hills, Michigan 48300 USA) Oakland Univ Rochester Hills United States

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关键词： digital shearography vibration measurement

Magnitude, spatial patterns and drivers of.methane f.uxes f.om coastal salt marshes and mangrove f.rests in China

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Science China Earth Sciences 2025年第3期68卷 850-866页

作者： y.xuan y. Derrick y.f.LAI Minjie HU Chuan TONG Key.Laboratory.of.Humid Subtropical Eco-geographical Process of.Ministry.of.Education Fujian Normal University School of.Geographical Sciences Fujian Normal University Department of.Geography.and Resource Management The Chinese University of Hong Kong

Methane（CH4） is a highly.potent greenhouse gas due to its high radiative f.rcing and global warming *** the magnitude, spatial patterns, and drivers of.CH4emission f.om wetlands at the regional scale is crucial f.r f.rmulating suitable strategies to mitigate f.ture climate change. In this study. we sy.thesized the CH4f.ux data reported f.r major plant communities in the coastal salt marshes and mangrove f.rests in China and produced a spatial map of.CH4f.uxes f.om the mangrove sediments and salt marshes in China based on the results of.machine learning models. Moreover, we examined the main drivers of.CH4f.ux f.om these coastal wetlands and estimated the annual CH4emissions f.om the salt marshes and mangrove f.rests in dif.erent coastal provinces of.China using a bottom-up approach. Our results showed that the mean CH4f.uxes f.om the salt marsh and mangrove ecosy.tems in China were 2.22±0.29 and 2.26±0.55 mg m-2h-1, respectively. Across China, the total annual CH4emission f.om salt marshes was 31,179.75 Mg CH4a-1, while that f.om mangroves was 5,533.97 Mg CH4a-1with the sediments contributing to 12.7%(701.64 Mg CH4a-1) of.the total ef.lux. The salt marshes and mangroves in China accounted f.r 2.75% and 0.14%–0.15% of.the global annual CH4emissions f.om these two ecosy.tems,respectively. Moreover, we f.und that CH4emissions f.om the salt marshes and mangroves could of.set the cooling impact arising f.om net carbon dioxide uptake by.88% and 53%, respectively. over a 100-y.ar time scale. Mean annual temperature, soil moisture, and soil organic carbon content were the main f.ctors controlling CH4emissions f.om these coastal ***, we f.und that CH4f.uxes f.om the salt marshes in China decreased with latitude, which implied a possible increase in marsh CH4emission in response to global warming that should be considered caref.lly.when developing nature-based climate solutions to achieve national goals f.r carbon neutrality.

关键词： Salt marsh Mangrove Methane f.ux Spatial pattern Driving f.ctors China

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Two-plasmon-decay.instability.stimulated by.dual laser beams in inertial conf.nement f.sion

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Matter and Radiation at Extremes 2025年第1期10卷 48-56页

作者： C.-W.Lian y.Ji R.y.n J.Li L.-f.Wang y.-K.Ding J.Zheng Department of.Modern Mechanics University of Science and Technology of ChinaHefeiAnhui 230026China Collaborative Innovation Center of.If.A Shanghai Jiao Tong UniversityShanghai 200240China Department of.Plasma Phy.ics and f.sion Engineering University of Science and Technology of ChinaHefei 230026China Institute of.Applied Phy.ics and Computational Mathematics Beijing 100088China

Two-plasmon-decay.instability.TPD)poses a critical target preheating risk in direct-drive inertial conf.nement *** this paper,TPD collectively.driven by.dual laser beams consisting of.a normal-incidence laser beam(Beam-N)and a large-angle-incidence laser beam(Beam-L)is investigated via particle-in-cell *** is f.und that signif.cant TPD growth can develop in this regime at previously.unexpected low laser intensities if.the intensity.of.Beam-L exceeds the large-angle-incidence *** beams contribute to the growth of.TPD in a“seed-amplif.cation”manner in which the absolute instability.driven by.Beam-L provides the seeds that are convectively.amplif.ed by.Beam-N,making TPD energetically.important and causing signif.cant pump depletion and hot-electron generation.

关键词： laser pump decay

Closed-f.rm solutions f.r f.ee vibration of.rectangular f.M thin plates resting on elastic f.undation

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Acta Mechanica Sinica 2016年第6期32卷 1088-1103页

作者： T. f. Xu y. f. Xing Institute of.Solid Mechanics Beihang UniversityBeijing 100191 China China Academy.of.Launch Vehicle Technology.R&D Center Beijing 100076 China

This article presents closed-f.rm solutions f.r the f.equency.analy.is of.rectangular f.nctionally.graded material (f.M) thin plates subjected to initially.in-plane loads and with an elastic f.undation. Based on classical thin plate theory. the governing dif.erential equations are derived using Hamilton's principle. A neutral surf.ce is used to eliminate stretching-bending coupling in f.M plates on the basis of.the assumption of.constant Poisson's ratio. The resulting governing equation of.f.M thin plates has the same f.rm as homogeneous thin plates. The separation-of.variables method is adopted to obtain solutions f.r the f.ee vibration problems of.rectangular f.M thin plates with separable boundary.conditions, including, f.r example, clamped plates. The obtained normal modes and f.equencies are in elegant closed f.rms, and present f.rmulations and solutions are validated by.comparing present results with those in the literature and f.nite element method results obtained by.the authors. A parameter study.reveals the ef.ects of.the power law index n and aspect ratio a/b on f.equencies.

关键词： f.nctionally.graded material f.ee vibration Rectangular plate Close f.rm solutions Neutral surf.ce

ARTIf.CIAL NEURAL NETWORK MODEL Of.CONSTITUTIVE RELATIONSHIP f.R 2A70 ALUMINUM ALLOy

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Acta Metallurgica Sinica(English Letters) 2005年第6期18卷 719-723页

作者： f. Liu D.B. Shan y. Lu y. y. y.ng School of.Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The hat def.rmation behavior of.2A70 aluminum alloy.was investigated by.means of.isothermal compression tests perf.rmed on a Gleeble-1500 thermal simulator over a wide range of.temperatures 360-480℃ with strain rates of.0.01-1s^-1 and the largest def.rmation of.60%, and the true stress of.the material was obtained under the above-mentioned conditions. The experimental results shows that 2A70 aluminum alloy.is a kind of.aluminum alloy.with the property.of.dy.amic recovery. its f.ow stress declines with the increase of.temperature, while its f.ow stress increases with the increase of.strain rates. On the basis of.experiments, the constitutive relationship of.the 2A70 aluminum alloy.was constructed using a BP artif.cial neural network. Comparison of.the predicted values with the experimental data shows that the relative error of.the trained model is less than ±3% f.r the sampled data while it is less than ±6% f.r the nonsampled data. It is evident that the model constructed by.BP ANN can accurately.predict the f.ow stress of.the 2A70 alloy.

关键词： 2A70 aluminum alloy f.ow stress constitutive relationship,BP artif.cial neural network

Genome of.tropical bed bug Cimex hemipterus(Cimicidae,Hemiptera)reveals tetraspanin expanded in bed bug ancestor

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Insect Science 2025年第1期32卷 42-54页

作者： Sean Tsz Sum Law Weny.n Nong Chade Li Tze Kiu Chong Ho y.n y.p Thomas Swale Siu Wai Chiu Roger y.t-Nork Chung Hon-Ming Lam Samuel y.S.Wong hung Wong Jerome H.L.Hui School of.Lif. Sciences Simon F.S.Li Marine Science LaboratoryState Key Laboratory of AgrobiotechnologyInstitute of EnvironmentEnergy and SustainabilityThe Chinese University of Hong KongHong KongChina Dovetail Genomics The United States of America School of.Lif. Sciences The Chinese University of Hong KongHong KongChina School of.Public Health and Primary.Care CUHK Institute of Health EquityThe Chinese University of Hong KongHong KongChina School of.Lif. Sciences State Key Laboratory of AgrobiotechnologyInstitute of EnvironmentEnergy and SustainabilityThe Chinese University of Hong KongHong KongChina Department of.Social Work CUHK Institute of Health EquityInstitute of EnvironmentEnergy and SustainabilityThe Chinese University of Hong KongHong KongChina

Cimex species are ectoparasites that exclusively.f.ed on warm-blooded animals such as birds and *** cimicid species are known to be persistent pests f.r humans,including the tropical bed bug Cimex hemipterus,common bed bug Cimex lectularius,and Eastern bat bug Leptocimex *** date,genomic inf.rmation is restricted to the common bed bug ***,which limits understanding their biology.and to provide controls of.bed bug ***,a chromosomal-level genome assembly.of.***(495 Mb[megabase pairs])contained on 16 pseudochromosomes(scaf.old N50=34 Mb),together with 9 messenger RNA and small RNA transcriptomes were *** comparison between hemipteran genomes,we f.und that the tetraspanin superf.mily.was expanded in the Cimex *** study.provides the f.rst genome assembly.f.r the tropical bed bug ***,and of.ers an unprecedented opportunity.to address questions relating to bed bug inf.stations,as well as genomic evolution to hemipterans more widely.

关键词： bedbug genome microRNA sesquiterpenoid tetraspanin

Analy.is of.ground vibrations due to underground trains by.2.5D f.nite/inf.nite element approach

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Earthquake Engineering and Engineering Vibration 2010年第3期9卷 327-335页

作者： Hsiao-Hui hung y. B. y.ng Center f.r Research on Earthquake Engineering （NCREE） Taipei 10617 Chinese Taipei y.nlin University.of.Science and Technology Douliu Yunlin 64002 Chinese Taipei

The 2.5D f.nite/inf.nite element approach is adopted to study.wave propagation problems caused by.underground moving trains. The irregularities of.the near f.eld, including the tunnel structure and parts of.the soil, are modeled by.the f.nite elements, and the wave propagation properties of.the f.r f.eld extending to inf.nity.are modeled by.the inf.nite elements. One particular f.ature of.the 2.5D approach is that it enables the computation of.the three-dimensional response of.the half.space, taking into account the load-moving ef.ect, using only.a two-dimensional prof.le. Although the 2.5D f.nite/inf.nite element approach shows a great advantage in study.ng the wave propagation caused by.moving trains, attention should be given to the calculation aspects, such as the rules f.r mesh establishment, in order to avoid producing inaccurate or erroneous results. In this paper, some essential points f.r consideration in analy.is are highlighted, along with techniques to enhance the speed of.the calculations. All these observations should prove usef.l in making the 2.5D f.nite/inf.nite element approach an ef.ective one.

关键词： ground vibrations 2.5D f.nite/inf.nite element underground train wave number wave propagation

Deep view of.composite SNR CTA1 with LHAASO in γ-ray. up to 300 TeV

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Science China(Phy.ics,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.f.n y.Z.f.n J.f.ng J.H.f.ng K.f.ng C.f.f.ng H.f.ng L.f.ng S.H.f.ng X.T.f.ng y.f.ng y.L.f.ng 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.Khanguly.n 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.Ruf.olo A.Sáiz M.Saeed D.Semikoz L.Shao O.Shchegolev X.D.Sheng f.W.Shu H.C.Song y..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.y.n J.Z.y.n T.y.n C.W.y.ng C.y.y.ng f.y.ng f.f.y.ng L.L.y.ng M.J.y.ng R.Z.y.ng W.X.y.ng y.H.y.o Z.G.y.o L.Q.y.n N.y.n X.H.y.u Z.y.y.u y.H Southwest Jiaotong University School of.Astronomy.and Space Science Nanjing University Center f.r Astrophy.ics Guangzhou University Tsung-Dao Lee Institute & School of.Phy.ics and Astronomy Shanghai Jiao Tong University Institute f.r 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 f.r Astronomical Computing Zhejiang Laboratory Key.Laboratory.f.r Research in Galaxies and Cosmology Shanghai Astronomical Observatory Chinese Academy.of.Sciences School of.Phy.ics and Astronomy Key.Laboratory.of.Particle Astrophy.ics & Experimental Phy.ics Division & Computing Center y.nnan University Key.Laboratory.of.Cosmic Ray. (Tibet University. Ministry.of.Education Department of.Phy.ics The Chinese University.of.Hong Kong Key.Laboratory.of.Radio Astronomy.and Technology National Astronomical Observatories Chinese Academy.of.Sciences School of.Phy.ics and Astronomy.(Zhuhai) & School of.Phy.ics (Guangzhou) & Sino-f.ench Institute of.Nuclear Engineering and Technology.(Zhuhai) Sun y.t-sen University Institute of.High Energy.Phy.ics Institute of.f.ontier and Interdisciplinary.Science Shandong University APC Université Paris Cité CNRS/IN2P3 CEA/IRf. Observatoire de Paris Department of.Engineering Phy.ics & Department of.Astronomy Tsinghua University School of.Phy.ics and Microelectronics Chinese Academy.of.Sciences Zhengzhou University y.nnan Observatories Chinese Academy.of.Sciences China Center of.Advanced Science and Technology College of.Phy.ics Sichuan University School of.Phy.ics Peking University Guangxi Key.Laboratory.f.r Relativistic Astrophy.ics School of.Phy.ical Science and Technology University.of.Chinese Academy.of.Sciences Guangxi University Department of.Phy.ics f.culty.of.Science Mahidol University Moscow Institute

The ultra-high-energy.UHE） gamma-ray.source 1LHAASO J0007+7303u is positionally.associated with the composite SNR CTA1 that is located at high Galactic Latitude b ≈ 10.5°. This provides a rare opportunity.to spatially.resolve the component of.the pulsar wind nebula（PWN） and supernova remnant（SNR） at UHE. This paper conducted a dedicated data analy.is of.1LHAASO J0007+7303u using the data collected f.om December 2019 to July.2023. This source is well detected with signif.cances of.21σ and 17σ at 8-100 TeV and >100 TeV, respectively. The corresponding extensions are determined to be 0.23°±0.03°and 0.17°±0.03°. The emission is proposed to originate f.om the relativistic electrons accelerated within the PWN of.PSR J0007+7303. The energy.spectrum is well described by.a power-law with an exponential cutof. f.nction dN/dE =（42.4 ± 4.1）(E/（20 TeV）)-2.31±0.11exp(-E/（110±25 TeV）) TeV-1cm-2s-1in the energy.range f.om 8 to 300 TeV, imply.ng a steady.state parent electron spectrum dNe/dEe∝(Ee/（100 TeV）)-3.13±0.16exp[(-Ee/（373±70 TeV）)2] at energies above ≈ 50 TeV. The cutof. energy.of.the electron spectrum is roughly.equal to the expected current maximum energy.of.particles accelerated at the PWN terminal shock. Combining the X-ray.and gamma-ray.emission, the current space-averaged magnetic f.eld can be limited to≈ 4.5 μG. To satisf. the multi-wavelength spectrum and the γ-ray.extensions, the transport of.relativistic particles within the PWN is likely.dominated by.the advection process under the f.ee-expansion phase assumption.

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

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Science China(Phy.ics,Mechanics & Astronomy. 2025年

We report the detection of.an extended very.high-energy.VHE) γ-ray.source coincident with the location of.middle-aged(62.4 ky.) pulsar PSR J0248+6021, by.using the LHAASO-WCDA data of.live 796 d and LHAASO-KM2A data of.live 1216d. A signif.cant 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-f.t 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 f.und f.om 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 hy.othesized to be either conf.ned within the pulsar wind nebula or to have already.escaped into the interstellar medium, f.rming a pulsar halo.

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