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Parametric dependence of collisional heating of highly magnetized over-dense plasma by(far-)infrared lasers

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High Power Laser Science and Engineering 2022年第4期10卷 7-13页

作者： k.li W.Yu Department of Physics College of ScienceShantou UniversityShantou 515063China Shanghai Institute of Optics and Fine Mechanics Chinese Academy of SciencesShanghai 201800China

Heating of over-dense plasma represents a long-standing quest in laser-plasma *** the strength of the magnetic field is above the critical value,a right-handed circularly polarized laser could propagate into and heat up the highly magnetized over-dense collisional plasma directly;the processes are dependent on the parameters of the laser,plasma and magnetic *** parametric dependence is fully studied both qualitatively and quantitatively,resulting in scaling laws of the plasma temperature,heating depth and energy conversion *** heating is also studied with the most powerful CO_(2) and strongest magnetic field in the world,where plasma with density of 10^(23)cm^(-3) and initial temperature of 1 keV is heated to around 10 keV within a depth of several *** novel phenomena are also discovered and discussed,that is,local heating in the region of high density,low temperature or weak magnetic field.

关键词： highly magnetized plasma over-dense plasma collisional heating parametric dependence

The role of earthquake-induced landslides in erosion and weathering from active mountain ranges:Progress and perspectives

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Science China Earth Sciences 2021年第12期64卷 2069-2082页

作者： Zhangdong JIN Robert G.HILTON AJoshua WEST Gen k.li Fei ZHANG Jin WANG Gaojun li Xuanmei FAN Meng-Long HSIEH State key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an710061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an710049China Department of Geography Durham UniversityDurhamDH13LEUK Department of Earth Sciences University of Southern CaliforniaLos AngelesCA90089USA Division of Geological and Planetary Sciences California Institute of TechnologyPasadenaCA91125USA School of Land Engineering Chang’an UniversityXi’an710054China Department of Earth and Planetary Sciences Nanjing UniversityNanjing210023China State key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China Department of Earth and Environmental Sciences Taiwan Chung Cheng UniversityChiayi600China

Earthquakes play a fundamental role in the evolution of Earth’s topography through co-seismic uplift and subsidence,as well as erosion through widespread landslides induced by ground ***-induced landslides can result in exceptional increases in the transfer of mass from landscapes,supplying sediment to rivers where impacts can last for decades or *** can also erode vegetation and soils,in addition to exposing freshly ground rock mass,which can both result in regionally significant carbon *** work has sought to quantify the fluxes,rates,and temporal patterns of the impacts on earth surface processes generated by these tectonic *** this review,we focus on the impacts of earthquake-induced landslides on erosion and sediment flux,river water chemistry,and carbon export through the lens of the well-studied 2008 Wenchuan *** then discuss these themes in the context of works from the 1999 Taiwan Chi-Chi earthquake,2015 Nepalese Gorkha earthquake,and New Zealand historical earthquakes,altogether highlighting an important role of earthquake-induced landslides in erosion and weathering along tectonically active mountain *** suggest that more monitoring,geochemical tracing,paleo-records,and/or modelling studies are needed to compare the processes and fluxes of catchment erosion and weathering before and after earthquake events,which will help to deepen our understanding not only of the impacts of earthquake-induced landslides on earth surface processes,but also the linkage among high magnitude events,continental erosion and weathering,and the long-term global carbon cycle.

关键词： Earthquake Erosion Chemical weathering The carbon cycle Tectonically active mountain ranges

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Modeling of a SrCe_(0.95)Yb_(0.05)O_3-αHollow Fibre Membrane Reactor for Methane Coupling

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Chinese Journal of Chemical Engineering 2003年第3期11卷 289-296页

作者：谭小耀杨乃涛 k.li Fuel Cell Research Center Shandong University of TechnologyZibo 255012China Department of Chemical Engineering University of BathClaverton DownBathBA2 7AYU.K.

Proton-hole mixed conductor, SrCeo.95Yb0.05O3-α(SCYb), has the potential to be used as a membrane for dehydrogenation reactions such as methane coupling due to its high C2-selectivity and its simplicity for fabricating reactor systems. In addition, the mixed conducting membrane in the hollow fibre geometry is capable of providing high surface area per unit volume. In this study, mechanism of methane coupling reaction on the SCYb membrane was proposed and the kinetic parameters were obtained by regression of experimental data. A mathematical model describing the methane coupling in the SCYb hollow fibre membrane reactor was also developed. With this mathematical model, various operating conditions such as the operation mode, operation pressure and feed concentrations affecting performance of the reactor were investigated. The simulation results show that the cocurrent flow in the reactor exhibits higher conversion of methane and higher yield of ethylene compared to the countercurrent flow. In order to achieve the highest C2 yield, especially of ethylene, pure methane should be used as feed and the operating pressure be 300 kPa. Air can be used as the source of oxygen for the reaction and its optimum feed velocity is twice of the methane feed velocity. The air pressure in the lumen side should be kept the same as or slightly lower than the pressure of shell side.

关键词： hollow fibre membrane mixed conductor methane coupling

Characteristic Analysis of the Solid Oxide Fuel Cell with Proton Conducting Ceramic Electrolyte

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Chinese Journal of Chemical Engineering 2005年第1期13卷 107-117页

作者：谭小耀孟波杨乃涛 k.li Fuel Cell Research Center Shandong University of Technology Zibo 255012 China Department of Chemical Engineering and Chemical Technology Imperial College London London SW7 2AZU.K.

An electrolyte model for the solid oxide fuel cell (SOFC) with proton conducting perovskite electrolyte is developed in this study, in which four types of charge carriers including proton, oxygen vacancy (oxide ion), free electron and electron hole are taken into consideration. The electrochemical process within the SOFC with hydrogen as the fuel is theoretically analyzed. With the present model, the effects of some parameters, such as the thickness of electrolyte, operating temperature and gas composition, on the ionic transport (or gas permeation) through the electrolyte and the electrical performance, i.e., the electromotive force (EMF) and internal resistance of the cell, are investigated in detail. The theoretical results are tested partly by comparing with the experimental data obtained from SrCe0.95M0.05O3-α, (M=Yb, Y) cells.

关键词： solid oxide fuel cell proton conducting ceramic perovskite oxide electrolyte

Achieving ultrahigh electromechanical properties with high TC in PNN-PZT textured ceramics

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Journal of Materials Science & Technology 2024年第8期175卷 258-265页

作者： Q.Wang L.Bian k.li Y.C.liu Y.L.Yang B.Yang W.W.Cao School of Instrumentation Science and Engineering Harbin Institute of TechnologyHarbin 150080China Guangdong Provincial key Laboratory of Electronic Functional Materials and Devices Huizhou UniversityHuizhou 516001China Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150080China

textured Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)(PNN-PZT)ceramics were prepared by templated grain growth(TGG)technique using 0.36PNN-x PZ-(0.64-x)PT(x=0.23,0.25 and 0.27)powder *** template content was derived to achieve the best electromechanical properties of textured *** piezoelectric coefficient d33=1165 pC/N,Curie temperature T_(C)=197℃,longitudinal mode electrome-chanical coupling factor k33=0.86 and a very large effective piezoelectric strain coefficient d_(33)^(*)=2041 pm/V were simultaneously achieved at the morphotropic phase boundary(MPB)composition(x=0.25)with 3 vol.%BaTiO_(3)(BT)*** structures of textured ceramics were analyzed in detail to reveal the origin of these high piezoelectric and electromechanical properties.

关键词： Pb(Ni_(1/3)Nb_(2/3))O_(3)-PbZrO_(3)-PbTiO_(3)(PNN-PZT) ceramics MPB composition Texture engineering Electromechanical properties Domain structure

Grain boundary and microstructure engineering of Inconel 690 cladding on stainless-steel 316L using electron-beam powder bed fusion additive manufacturing

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Journal of Materials Science & Technology 2019年第2期35卷 351-367页

作者： I.A.Segura L.E.Murr C.A.Terrazas D.Bermudez J.Mireles V.S.V.Injeti k.li B.Yu R.D.k.Misra R.B.Wicker W.M.keck Center for 3D Innovation The University of Texas at El Paso Department of Mechanical Engineering The University of Texas at El Paso Department of Metallurgical Materials and Biomedical Engineering The University of Texas at El Paso

This research explores the prospect of fabricating a face-centered cubic(fcc) Ni-base alloy cladding(Inconel 690) on an fcc Fe-base alloy(316 L stainless-steel) having improved mechanical properties and reduced sensitivity to corrosion through grain boundary and microstructure engineering concepts enabled by additive manufacturing(AM) utilizing electron-beam powder bed fusion(EPBF). The unique solidification and associated constitutional supercooling phenomena characteristic of EPBF promotes[100] textured and extended columnar grains having lower energy grain boundaries as opposed to random, high-angle grain boundaries, but no coherent {111} twin boundaries characteristic of conventional thermo-mechanically processed fcc metals and alloys, including Inconel 690 and 316 L *** addition to [100] textured grains, columnar grains were produced by EPBF fabrication of Inconel 690 claddings on 316 L stainless-steel substrates. Also, irregular 2–3 μm diameter, low energy subgrains were formed along with dislocation densities varying from 108 to 109 cm^2, and a homogeneous distribution of Cr_(23)C_6 precipitates. Precipitates were formed within the grains(with ~3 μm interparticle spacing),but not in the subgrain or columnar grain boundaries. These inclusive, hierarchical microstructures produced a tensile yield strength of 0.527 GPa, elongation of 21%, and Vickers microindentation hardness of 2.33 GPa for the Inconel 690 cladding in contrast to a tensile yield strength of 0.327 GPa, elongation of 53%, and Vickers microindentation hardness of 1.78 GPa, respectively for the wrought 316 L stainlesssteel substrate. Aging of both the Inconel 690 cladding and the 316 L stainless-steel substrate at 685?C for50 h precipitated Cr_(23)C_6 carbides in the Inconel 690 columnar grain boundaries, but not in the low-angle(and low energy) subgrain boundaries. In contrast, Cr_(23)C_6 carbides precipitated in the 316 L stainless-steel grain boundaries, but not in the low energy

关键词： Additive manufacturing Electron-beam powder bed fusion (EPBF) Inconel 690 cladding 316L stainless steel Grain boundary engineering Materials characterization Mechanical properties

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化石有机碳风化及其生物地球化学循环效应

中国科学：地球科学 2024年第6期54卷 2098-2102页

作者：李高军 Gen k.li 南京大学地球与行星科学系南京210023 Department of Earth Science University of CaliforniaSanta BarbaraCA 93106USA

生命过程是地球物质循环有别于其他行星最重要的特征之一.生命过程的重要一环是碳基生物通过光合作用将大气CO_(2)转化为有机形式的碳化合物,并释放氧气(Derry, 2014).化石有机碳,亦称为岩石有机碳,是一类在漫长地质历史时期积累并石化... 详细信息

生命过程是地球物质循环有别于其他行星最重要的特征之一.生命过程的重要一环是碳基生物通过光合作用将大气CO_(2)转化为有机形式的碳化合物,并释放氧气(Derry, 2014).化石有机碳,亦称为岩石有机碳,是一类在漫长地质历史时期积累并石化在岩石圈中的独特有机碳.化石有机碳与碳酸盐为主的无机形式碳一起成为固体地球去气作用CO_(2)释放最主要的汇,共同组成地球系统的两大核心碳储库.

关键词：固体地球碳化合物生物地球化学循环物质循环去气作用有机碳漫长地质历史碳储库

The non-uniformity study under geo-magnetic field of 20-inch MCP-PMT for LHAASO

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Radiation Detection Technology and Methods 2024年第3期8卷 1377-1389页

作者： C.C.liu B.Gao S.X.Lu M.J.Chen X.H.You k.li lin liu W.k.Gao Zhengzhou University Zhengzhou450001China Institute of High Energy Physics Chinese Academy of SciencesBeijing100049China TIANFU Cosmic Ray Research Centre 1500 Ke Zhi RoadChengduChina University of Chinese Academy of Sciences Beijing100043China

Purpose The large diameter photon sensors are widely applied in astroparticle physics and neutrino physics *** to its large size,the geo-magnetic effect cannot be *** this work,one 20-inch MCP-PMT are scanned under geo-magnetic field and magnetic shielding environment,and finally,the multi-parameter scanning results are *** In order to evaluate the response of MCP-PMTs,an automatic spherical scanning system based on stepper motor and quartz fiber was established.A comprehensive multi-point scanning was performed on the entire 20-inch MCP-PMT,and a multi parameter data scanning model was *** self-developed magnetic shielding was used to demonstrate the improvement of magnetic shielding on the ratio of signals,charge uniformity,and time characteristics of the 20-inch *** By comparing the results with and without magnetic shielding,it can be concluded that with magnetic shielding,the variation in charge spectrum and the ratio of signals are relatively *** the same time,the composition of photon time spectrum has become *** relative transit time and time spread of photons are reduced to a certain extent,and the uniformity of both is also *** The use of magnetic shielding has improved the various performance of MCP-PMT,preparing for future LHAASO and other experiments.

关键词： Photon-sensor Geo-magnetic effect Non-uniformity

A Frequency Determination Method for Digitized NMR Signals

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Communications in Computational Physics 2014年第5期15卷 1343-1351页

作者： H.Yan k.li R.khatiwada E.Smith W.M.Snow C.B.Fu P.-H.Chu H.Gao W.Zheng Indiana University BloomingtonIndiana 47408USA Center for Exploration of Energy and Matter Indiana UniversityBloomingtonIN 47408USA Department of Physics Shanghai Jiaotong UniversityShanghai200240China Triangle Universities Nuclear Laboratory and Department of Physics Duke UniversityDurhamNorth Carolina 27708USA.

We present a high precision frequency determination method for digitized NMR FID *** method employs high precision numerical integration rather than simple summation as in many other *** no independent knowledge of the other parameters of a NMR FID signal(phaseφ,amplitude A,and transverse relaxation time T_(2))this method can determine the signal frequency f_(0)with a precision of 1/(8π^(2)f_(0)^(2)T_(2)^(2))if the observation time T≫T_(2).The method is especially convenient when the detailed shape of the observed FT NMR spectrum is not well *** T2 is+∞and the signal becomes pure sinusoidal,the precision of the method is 3/(2π^(2)f_(0)^(2)T_(2))which is one order more precise than the±1 count error induced precision of a typical frequency *** of this method shows that the integration reduces the noise by bandwidth narrowing as in a lock-in amplifier,and no extra signal filters are *** a pure sinusoidal signal we find from numerical simulations that the noise-induced error in this method reaches the Cramer-Rao Lower Band(CRLB)on frequency *** the damped sinusoidal case of most interest,the noise-induced error is found to be within a factor of 2 of CRLB when the measurement time T is 2 or 3 times larger than *** discuss possible improvements for the precision of this method.

关键词： NMR FID numerical integration frequency determination noise reduction