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许家窑泥河湾沉积物的岩石磁学性质

中国科学（D辑） 2002年第4期32卷 271-278页

作者：王喜生 lφvlie reidar 苏朴中国地质科学院地质力学研究所 Institute of Solid Earth Physics Allegt 41 BeygenNorway 太原理工大学太原030024

对许家窑泥河湾河湖相沉积物开展的一系列岩石磁学实验结果显示:磁铁矿、磁赤铁矿和赤铁矿为主要的载磁矿物;低温磁化率和低温剩磁测量是查明磁铁矿、磁赤铁矿化及超顺磁颗粒存在的非常有效的手段;尽管在局部深度上部分磁铁矿可能经历... 详细信息

对许家窑泥河湾河湖相沉积物开展的一系列岩石磁学实验结果显示:磁铁矿、磁赤铁矿和赤铁矿为主要的载磁矿物;低温磁化率和低温剩磁测量是查明磁铁矿、磁赤铁矿化及超顺磁颗粒存在的非常有效的手段;尽管在局部深度上部分磁铁矿可能经历了低温氧化,但SD/MD磁铁矿颗粒的大量存在仍是沉积物磁化率增强的主要原因之一;SD/MD磁铁矿和赤铁矿为碎屑成因,由二者为主要磁性载体的特征剩磁（ChRM）反映了沉积物形成时的原始磁场,而磁赤铁矿则可能代表了叠加于原生剩磁上后生的化学成分.

关键词：饱和等温剩磁磁滞回线沉积剩磁居里点泥河湾沉积物岩石磁学性质

三门峡地区黄土l_9的重磁化现象及原因探析

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第四纪研究 2005年第4期25卷 453-460页

作者：王喜生杨振宇 lvlie reidar 裴军令中国地质科学院地质力学研究所古地磁实验室南京大学地球科学系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 Bergen Allegaten 41 N-5007 Bergen Norway

对黄河三门峡地区曹村黄土剖面l1至l13(年代持续约1.1Ma)的高分辨率古地磁研究发现:布容/松山界线位于第8层古土壤(S8)的顶部,贾拉米洛正极性亚时的顶、底界分别位于S10和l13的顶部,上述古地磁极性转换界线与洛川标准剖面一致。“上粉... 详细信息

对黄河三门峡地区曹村黄土剖面l1至l13(年代持续约1.1Ma)的高分辨率古地磁研究发现:布容/松山界线位于第8层古土壤(S8)的顶部,贾拉米洛正极性亚时的顶、底界分别位于S10和l13的顶部,上述古地磁极性转换界线与洛川标准剖面一致。“上粉砂层”(l9)的绝大多数样品特征剩磁方向与现代地磁场方向一致,而其中的弱发育古土壤层(l9SS1)则呈预期的反极性特征。综合l9的厚度、岩性和岩石磁学特征,认为这一巨厚的正极性带可能反映了完全由岩性所控制的重磁化特征。对于l9重磁化的原因,似乎很难用后生的化学剩磁和粘滞剩磁来解释。文章尝试性地提出,可能在l9沉积后的间冰期(对应S8)和布容正极性时内气候较湿润的时期,由于雨水的向下渗透而诱导了其中强磁性矿物(磁铁矿)在沉积后随地磁场方向的变化而进行了重新排列。

关键词：黄土三门峡重磁化极性事件

Regional stress field around the Taigu fault zone in Shanxi Province,China

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Earthquake Science 2015年第5期28卷 333-345页

作者： Bin li Zihong li Mathilde B.S?rensen reidar l?vlie liqiang liu Kuvvet Atakan Earthquake Administration of Shanxi Province Department of Earth Science University of Bergen State Key laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration

A comprehensive study on regional stress field around the Taigu fault zone in Shanxi Province, China, was performed in this study. To get a better understanding of the present-day stress status in this area, 31 focal mecha- nisms of Ml 〉3 earthquakes since 1965 were compiled, and the best stress tensor was then inverted based on the database. Additionally, magnetic fabrics along the Taigu fault zone were investigated to get an indication of the regional stress field in the past. Our results show that the present-day stress field around the Taigu fault zone is characterized by astable NW-SE extension with a strike- slip component, consistent with the geological surveys and recent GPS data. Results from magnetic fabrics indicate that the orientations of principal stress axes from magnetic fabrics of sedimentary rocks in Neogene coincide to the orientations of principal stress axes from focal mecha- nisms. The south segment of the Taigu fault displays more complicated magnetic fabrics and more activity of mod- erate earthquakes. It is connected with the Mianshan west fault and intersects with NW-SE striking Fenyang fault and the north fault of the lingshi uplift at the south edge of Taiyuan basin. This may be the area needing more atten- tion in terms of seismic risk along the Taigu fault.

关键词： Focal mechanisms Stress tensor inversion Magnetic fabric Taigu fault Shanxi rift

On the functions of astrocyte-mediated neuronal slow inward currents

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Neural Regeneration Research 2024年第12期19卷 2602-2612页

作者： Balázs Pál Department of Physiology Faculty of MedicineUniversity of DebrecenDebrecenHungary

Slow inward currents are known as neuronal excitatory currents mediated by glutamate release and activation of neuronal extra synaptic N-met hyl-D-aspartate receptors with the contribution of *** events are significantly slower than the excitatory postsynaptic *** of slow inward currents are determined by seve ral factors including the mechanisms of astrocytic activation and glutamate release,as well as the diffusion pathways from the release site towards the extra synaptic recepto *** are stimulated by neuronal network activity,which in turn excite neurons,forming an astrocyte-neuron feedback *** as a consequence of brain edema,astrocytic swelling can also induce slow inward currents under pathological *** is a growing body of evidence on the roles of slow inward currents on a single neuron or local network *** events often occur in synchro ny on neurons located in the same astrocytic *** synchronization of neuronal excitability,slow inward currents also set synaptic strength via eliciting timing-dependent synaptic *** addition,slow inward currents are also subject to non-synaptic plasticity triggered by long-la sting stimulation of the excitatory *** note,there might be important regionspecific differences in the roles and actions triggering slow inward *** greater networks,the pathophysiological roles of slow inward currents can be better understood than physiological *** inward currents are identified in the pathophysiological background of autism,as slow inward currents drive early hypersynchrony of the neural *** inward currents are significant contributors to paroxysmal depolarizational shifts/interictal *** events are related to epilepsy,but also found in Alzheimer's disease,Parkinson's disease,and stroke,leading to the decline of cognitive *** with features overlapping with slow inward currents(excitatory,N-methyl-Dasp

关键词： astrocyte cortical spreading depolarization gliotransmission glutamate neural synchronization NMDA receptor paroxysmal depolarizational shift slow inward current

On calculating glacial isostatic adjustment

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Geodesy and Geodynamics 2024年第5期15卷 441-452页

作者： l.M.Cathles Cornell University IthacaNY 14853USA

Modeling the earth's fluid and elastic response to the melting of the glaciers of the last ice age is the most direct way to infer the earth's radial viscosity ***,we compare two methods for calculating the viscoelastic response to surface *** one,the elastic equation of motion is converted to a viscoelastic equation using the Correspondence *** the other,elastic deformation is added to the viscous flow as isostatic adjustment *** two modeling methods predict adjustment histories that are different enough to potentially impact the interpretation of the observed glacial isostatic adjustment(GIA).The differences arise from buoyancy and whether fluid displacements are subjected to hydrostatic *** methods agree if they use the same equations and boundary *** origin of the differences is determined by varying the boundary conditions and pre-stress application.

关键词： Glacial isostatic adjustment Viscoelastic normal modes Hydrostatic pre-stress Elastic buoyancy Correspondence principle

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l Silva l.A.O.Nunes S.M.lima l.H.C.Andrade Optical and Photothermal Spectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Non-adhesive and adhesive contacts of an elastic quarter-or eighth-space with freely sliding sides

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Friction 2024年第9期12卷 2052-2063页

作者： Qiang lI Valentin l.POPOV Technische Universität Berlin Berlin 10623Germany

The contact of an elastic quarter-or eighth-space is studied under the condition that the movement of the side surface of the quarter-space is constrained:It can slide freely along the plane of the side surface but its normal movement is blocked(for example,by a rigid wall).The solution of this contact problem can be easily achieved by additionally applying a mirrored load to an elastic ***-adhesive contact and the Johnson–Kendall–Roberts(JKR)-type adhesive contact between a rigid sphere and an elastic quarter-space under such a boundary condition is numerically simulated using the fast Fourier transform(FFT)-assisted boundary element method(BEM).Contacts of an elastic eighth-space are investigated using the same *** on the position of the sphere relative to the side edge,different contact behavior is *** the case of adhesive contact,the force of adhesion first increases with increasing the distance from the edge of the quarter-space,achieves a maximum,and decreases further to the JKR-value in large distance from the *** enhancement of the force of adhesion compared to the half-space-contact is associated with the pinning of the contact area at the *** provide the maps of the force of adhesion and their analytical approximations,as well as pressure distributions in the contact plane and inside the quarter-/eighth-space.

关键词： quarter-space eighth-space adhesion edge effect boundary element method(BEM)

Quantum vortices get stretched

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Frontiers of physics 2024年第3期19卷 225-227页

作者： Emanuel A.l.Henn São Carlos Institute of Physics University of São Paulo-PO Box 36913560-970São CarlosBrazil

Since its discovery, superfluidity [1,2] remains one of the most remarkable phenomena in quantum physics. The onset of the quantum regime in liquid helium is visually striking, when the fluid flows without dissipation or detaches from a rotating bucket, remaining still upon soft rotations. The same phenomenon is present in the context of ultracold bosonic quantum gases where, most of the time, superfluidity walks hand-in-hand with the transition to Bose−Einstein condensation [3].

关键词： quantum rotating rotation

Time-inconsistent stochastic linear-quadratic control problem with indefinite control weight costs

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Science China Mathematics 2024年第1期67卷 211-236页

作者： Qi lü Bowen Ma School of Mathematics Sichuan UniversityChengdu 610064China

A time-inconsistent linear-quadratic optimal control problem for stochastic differential equations is *** introduce conditions where the control cost weighting matrix is possibly *** such conditions,we obtain a family of closed-loop equilibrium strategies via multi-person differential *** result extends Yong’s work(2017) in the case of stochastic differential equations,where a unique closed-loop equilibrium strategy can be derived under standard conditions(namely,the control cost weighting matrix is uniformly positive definite,and the other weighting coefficients are positive semidefinite).

关键词： linear-quadratic optimal control problem time-inconsistent cost functional generalized Riccati equation indefinite control weight cost closed-loop equilibrium strategy