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黄土高原东北缘矾山剖面的古地磁新结果

第四纪研究 2012年第4期32卷 597-607页

作者：陈蕴王喜生裴军令 r.lφlie 中国地质科学院地质力学研究所古地磁实验室北京100081 Department of Earth Science University of BergenAllegaten 41N-5007 BergenNorway

黄土高原不同地区发育的黄土-古土壤序列在东亚冬、夏季风记录上存在一定的差异性,而目前的研究多集中在黄土高原腹地。本文以黄土高原东北缘北京邻区矾山剖面S_6～l_9段地层为研究对象,开展了详细的古地磁、岩石磁学、粒度及地球化学... 详细信息

黄土高原不同地区发育的黄土-古土壤序列在东亚冬、夏季风记录上存在一定的差异性,而目前的研究多集中在黄土高原腹地。本文以黄土高原东北缘北京邻区矾山剖面S_6～l_9段地层为研究对象,开展了详细的古地磁、岩石磁学、粒度及地球化学测试分析。结果表明:1)与黄土高原腹地典型剖面同时段地层相比,矾山黄土成壤程度偏低,所受夏季风的影响较黄土高原内部剖面偏弱;2)在黄土高原腹地l_8～S_8地层中广为记录的布容-松山地磁极性倒转界线(M/B)及其高频极性转换特征在该剖面并未被清晰地记录,却在"上粉砂层"—l_9的顶部记录了一个明显的正、反磁极性转换,而相对古强度参数均指示M/B可能应位于l_8的下部;3)该剖面l_9段地层记录了3个较稳定的正极性段落,推测可能是布容期重磁化的结果,而非短期地磁极性漂移;4)l_9下部约0.8m的地层记录了一段天然剩磁异常高值带,可能是瞬间极强磁场(如雷电)磁化的结果。

关键词：矾山黄土M/B l9重磁化

黄土高原东南缘黄土-古土壤序列的环境磁学研究

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黄土高原东南缘黄土-古土壤序列的环境磁学研究

奥斯陆(OSlO)裂谷带上的古地磁挪威卑尔根大学地球物理系

中国地球物理学会第22届年会

作者：王喜生杨振宇 r.l■vlie 裴军令孙知明中国地质科学院地质力学研究所南京大学地球科学系 Department of Earth Science University of Bergen N-5007 BergenNorway 中国地质科学院地质力学研究所中国地质科学院地质力学研究所

＜正＞目前,虽然对中国黄土-古土壤序列中古土壤磁化率增强的土壤成因模式已被广泛接受, 然而在由成土作用形成的超顺磁（SP）颗粒对磁化率（X）的贡献以及磁化率如何记录古气候变化等问题上还没有达成广泛的一致。由于磁化率是磁性矿...

＜正＞目前,虽然对中国黄土-古土壤序列中古土壤磁化率增强的土壤成因模式已被广泛接受, 然而在由成土作用形成的超顺磁（SP）颗粒对磁化率（X）的贡献以及磁化率如何记录古气候变化等问题上还没有达成广泛的一致。由于磁化率是磁性矿物的种类、含量和颗粒大小的综合反映,其值受源区物质的差异性、成壤期气候条件和降雨量及成土作用持续的时间等诸多因素的控制和影响。而饱和等温剩磁（SIrM）、非磁滞剩磁（ArM）、频率磁化率（Xfd％）等及其组合参数对不同粒径范围内磁性矿物含量

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世界地质 1984年第1期 81-85页

作者： K.M.Storetvedt S.Pedersen r.lφvlie E.Halvorsen 周富祥

我们回顾了奥斯陆(OSlO)地区最近的古地磁成果(有发表过的和未发表过的),包括沉积岩、菱长斑岩熔岩,互层玄武岩沉积层以及脉岩等资料。这些成果认为在裂谷带的南部和西部地区已经有前基阿玛(Kiaman)时代(即前石碳纪,距今300百万年)的大... 详细信息

我们回顾了奥斯陆(OSlO)地区最近的古地磁成果(有发表过的和未发表过的),包括沉积岩、菱长斑岩熔岩,互层玄武岩沉积层以及脉岩等资料。这些成果认为在裂谷带的南部和西部地区已经有前基阿玛(Kiaman)时代(即前石碳纪,距今300百万年)的大量岩浆作用。在前中生代时期主要的火成活动区看来是向北扩展了。因而,在晚石碳纪和或早二迭纪,火山活动似乎席卷整个 OSlO 地区.而在裂谷的北端(靠近布鲁蒙特(Erumurddal))熔岩流的喷出,发生在晚二迭纪.观察到构造变形晚于火山作用.很可能属于中生代时期。有晚于古生代时期.很可能在侏罗纪.看来至少有两次岩脉侵入脉动使奥斯陆(OSlO)区域受到了影响。

关键词：古地磁研究 OSlO 裂谷带火山活动岩脉岩石侵入体二迭纪石碳纪奥斯陆挪威

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author.links open overlay panel

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Particuology 2024年第8期91卷 211-225页

作者： Jack r.Grogan Andrei l.Nicuşan Christopher r.K.Windows-Yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of r.lling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** r.latively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of r.lling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of r.lling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction restitution

Deep bed filtration model for cake filtration and erosion

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Applied Mathematics and Mechanics(English Edition) 2024年第2期45卷 355-372页

作者： l.I.KUZMINA Y.V.OSIPOV A.r.PESTErEV Department of Applied Mathematics HSE UniversityMoscow 101000Russia Department of Computer Science and Applied Mathematics Moscow State University of Civil EngineeringMoscow 129337Russia

Many phenomena in nature and technology are associated with the filtration of suspensions and colloids in porous media. Two main types of particle deposition,namely, cake filtration at the inlet and deep bed filtration throughout the entire porous medium, are studied by different models. A unified approach for the transport and deposition of particles based on the deep bed filtration model is proposed. A variable suspension flow rate, proportional to the number of free pores at the inlet of the porous medium, is considered. To model cake filtration, this flow rate is introduced into the mass balance equation of deep bed filtration. For the cake filtration without deposit erosion,the suspension flow rate decreases to zero, and the suspension does not penetrate deep into the porous medium. In the case of the cake filtration with erosion, the suspension flow rate is nonzero, and the deposit is distributed throughout the entire porous medium. An exact solution is obtained for a constant filtration function. The method of characteristics is used to construct the asymptotics of the concentration front of suspended and retained particles for a filtration function in a gener.l form. Explicit formulae are obtained for a linear filtration function. The properties of these solutions are studied in detail.

关键词： deep bed filtration cake filtration porous medium particle deposition and erosion analytical solution concentration front

On an isotropic porous solid cylinder:the analytical solution and sensitivity analysis of the pressure

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1499-1522页

作者： H.ASGHArI l.MIllEr r.PENTA J.MErODIO Departamento de Matematica Aplicada a las TIC ETS de Ingenieria de Sistemas InformaticosUniversidad Politecnica de MadridMadrid 28031Spain School of Mathematics and Statistics University of GlasgowGlasgow G128QQU.K.

Within this work,we perform a sensitivity analysis to determine the influence of the material input parameters on the pressure in an isotropic porous solid *** provide a step-by-step guide to obtain the analytical solution for a porous isotropic elastic cylinder in terms of the pressure,stresses,and elastic *** obtain the solution by performing a laplace transform on the governing equations,which are those of Biot's poroelasticity in cylindrical polar *** enforce radial boundary conditions and obtain the solution in the laplace transformed domain before reverting back to the time *** sensitivity analysis is then carried out,considering only the derived pressure *** analysis finds that the time t,Biot's modulus M,and Poisson's ratio ν have the highest influence on the pressure whereas the initial value of pressure P_(0) plays a very little r.le.

关键词： sensitivity analysis laplace transform cylindrical polar coordinate Biot's modulus cylinder

SANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.r.Boyko l.V.Kalinovskaya A.A.Kampf r.r.Sadykov V.l.Yermolchyk Bogoliubov laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte Carlo event generator reneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are r.levant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Dual Additives for Stabilizing li Deposition and SEI Formation in Anode-Free li-Metal Batteries

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Energy & Environmental Materials 2024年第3期7卷 84-92页

作者： Baolin Wu Chunguang Chen Dmitri l.Danilov Zhiqiang Chen Ming Jiang rüdiger-A.Eichel Peter H.l.Notten Forschungszentrum Jülich(IEK-9) D-52425Jülich Germany rWTH Aachen University D-52074Aachen Germany lNM Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China Eindhoven University of Technology P.O.Box 5135600 MBEindhoven The Netherlands School of Electronics and Information Institute of Carbon Neutrality and New EnergyHangzhou Dianzi UniversityHangzhou 310018China University of Technology Sydney BroadwaySydney NSW 2007Australia

Anode-free li-metal batteries are of significant interest to energy storage industries due to their intrinsically high ***,the accumulative li dendrites and dead li continuously consume active li during *** results in a short lifetime and low Coulombic efficiency of anode-free li-metal *** effective electr.lyte additives can improve the li deposition homogeneity and solid electr.lyte interphase(SEI)stability for anode-free li-metal ***,we reveal that introducing dual additives,composed of liAsF6 and fluoroethylene carbonate,into a low-cost commercial carbonate electr.lyte will boost the cycle life and average Coulombic efficiency of NMC‖Cu anode-free li-metal *** NMC‖Cu anode-free li-metal batteries with the dual additives exhibit a capacity retention of about 75%after 50 cycles,much higher than those with bare electr.lytes(35%).The average Coulombic efficiency of the NMC‖Cu anode-free li-metal batteries with additives can maintain 98.3%over 100 *** contrast,the average Coulombic efficiency without additives rapidly decline to 97%after only 50 *** situ raman measurements reveal that the prepared dual additives facilitate denser and smoother.li morphology during li *** dual additives significantly suppress the li dendrite growth,enabling stable SEI formation on anode and cathode *** results provide a broad view of developing low-cost and high-effective functional electr.lytes for high-energy and long-life anode-free li-metal batteries.

关键词： anode-free lithium metal battery dual additives in situ raman li growth SEI formation

robust Machine learning Mapping of sEMG Signals to Future Actuator Commands in Biomechatronic Devices

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Journal of Bionic Engineering 2024年第1期21卷 270-287页

作者： Ali Nasr Sydney Bell rachel l.Whittaker Clark r.Dickerson John McPhee Systems Design Engineering University of WaterlooWaterloo N2L 3G1Canada Kinesiology and Health Sciences University of WaterlooWaterloo N2L3G3Canada

A machine learning model for regression of interrupted Surface Electromyography(sEMG)signals to future contr.l-oriented signals(e.g.,robot’s joint angle and assistive torque)of an active biomechatronic device for high-level myoelectric-based hierarchical contr.l is proposed.A recurrent Neur.l Network(rNN)was trained using output data,initially obtained from offline optimization of the biomechatronic(human–robot)device and shifted by the prediction *** input of the rNN consisted of interrupted sEMG signals(to mimic signal disconnections)and previous kinematic signals of the assistive *** rNN with a 0.1-s prediction horizon could predict the contr.l-oriented joint angle and assistive torque with 92%and 86.5%regression accuracy,respectively,for the test *** proposed approach permits a fast,predictive,and direct estimation of contr.l-oriented signals instead of an iterative process that optimizes assistive torque in the inverse dynamic simulation of a multibody human–robot *** with these interrupted input signals significantly improves the regression accuracy in the case of sEMG signal *** robust Predictive Contr.l-oriented Machine learning(robust-MuscleNET)model can support volitional high-level myoelectric-based contr.l of biomechatronic devices,such as exoskeletons,prostheses,and assistive/resistive *** work should study the application to prosthesis contr.l as well as the repeatability of the high-level contr.ller with electrode *** low-level hierarchical contr.ller that manages the human–robot interaction,the assistance/resistance strategy,and the actuator coordination should also be studied.

关键词： Myoelectric-based contr.l-Surface electromyography Machine learning Multibody system dynamics Exoskeleton Bionic