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New advances in the study of Tethyan Geodynamic System

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Science china Earth sciences 2024年第3期67卷 874-878页

作者： Lin ding State Key Laboratory of Tibetan Plateau Earth System Science(LATPES) Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Tethyan Ocean was initially proposed by Austrian geologist Eduard Suess in 1893. The study of the Tethyan evolution by European geologists has led to the development of modern geology, but not to the establishment of plate tectonics theory(Trümpy, 2001). With the progress in various studies, the concept of Tethys has evolved from a Mesozoic ocean into three long-term evolving oceans:Proto-Tethys, Paleo-Tethys, and Neo-Tethys (Figure 1), and their life cycles cover the entire Phanerozoic era (Wu et al., 2020).

关键词： geology Mesozoic ocean

Contemporary crustal movement of continental china obtained by global positioning system(GPS) measurements

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chinese Science Bulletin 2001年第18期46卷 1552-1554,1588页

We obtain a unified horizontal velocity field of continental china and vicinity through measurements at 81 GPS stations provided by the National Key Infrastructure Project, Crustal Movement Observation Network of china. The velocity field delineates patterns of movements and deformation of active crustal blocks in continental china under the Eurasia-fixed reference frame. The space-based geodesy also clearly shows for the first time the horizontal movementand deformation of continental china induced by indentation of the Indian plate. The data provide kinematic constraints for simulating dynamic process of continental litho-spheric deformation.

关键词： crustal movement velocity field tectonic deformation.

Chiral quantum heating and cooling with an optically controlled ion

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Light(Science & Applications) 2024年第7期13卷 1393-1400页

作者： Jin-Tao Bu Jian-Qi Zhang Ge-Yi ding Jia-Chong Li Jia-Wei Zhang Bin Wang Wen-Qiang ding Wen-Fei Yuan Liang Chen Qi Zhong Ali Keçebaş Şahin KÖzdemir Fei Zhou Hui jing Mang Feng State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and MathematicsInnovation Academy of Precision Measurement Science and TechnologyChinese Academy of Sciences430071 WuhanChina. University of the chinese academy of sciences 100049 BeijingChina. Research Center for Quantum Precision Measurement Guangzhou Institute of Industry Technology511458 GuangzhouChina. Department of Engineering Science and Mechanics and Materials Research InstitutePennsylvania State UniversityUniversity ParkState CollegePA 16802USA. Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal University410081 ChangshaChina. Department of Physics Zhejiang Normal University321004 JinhuaChina

Quantum heat engines and refrigerators are open quantum systems,whose dynamics can be well understood using a non-Hermitian formalism.A prominent feature of non-Hermiticity is the existence of exceptional points(EPs),which has no counterpart in closed quantum *** has been shown in classical systems that dynamical encirclement in the vicinity of an EP,whether the loop includes the EP or not,could lead to chiral mode ***,we show that this is valid also for quantum systems when dynamical encircling is performed in the vicinity of their Liouvillian EPs(LEPs),which include the effects of quantum jumps and associated noise—an important quantum feature not present in previous *** demonstrate,using a Paul-trapped ultracold ion,the first chiral quantum heating and refrigeration by dynamically encircling a closed loop in the vicinity of an *** witness the cycling direction to be associated with the chirality and heat release(absorption)of the quantum heat engine(quantum refrigerator).Our experiments have revealed that not only the adiabaticity breakdown but also the Landau–Zener–Stückelberg process play an essential role during dynamic encircling,resulting in chiral thermodynamic *** observations contribute to further understanding of chiral and topological features in non-Hermitian systems and pave a way to exploring the relation between chirality and quantum thermodynamics.

关键词： quantum chiral dynamical

A～6 Ma chemical weathering history,the grain size dependence of chemical weathering intensity,and its implications for provenance change of the chinese loess-red clay deposit

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A～6 Ma chemical weathering history,the grain size dependenc...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： Shangfa Xiong~*,zhongli ding,Yuanjian Zhu,Ru Zhou,Haijian Lu Key Laboratory of Cenozoic geology and Environment,institute of geology & geophysics,chinese academy of sciences,100029 beijing,china

Major element chemical analyses of the Baishui loess—red clay sequence(35°24’ 10"N,106°54’ 43"E, Gansu Province,china) reveal that,the chemical weathering intensities inferred from CIA(chemical index of alteration) values have progressively weakened and increased in amplitude with decreasing age. The general trend of the CIA can be correlated well with the oxygen isotope variations of the deep sea *** of multiple size fractions(1 Ma onward,CIA values for all size fractions decrease,indicating an increasing input of fresh or poorly weathered detritus in the desert source regions of loess *** variations in the KO/AlO, NaO/AlO,CaO/AlO and MgO/AlO ratios from 4.5 Ma to about 0.6 Ma in bulk and size fractioned samples may reflect provenance change as well as changing chemical weathering processes.

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A stability formula for Lax-Wendroff methods with fourth-order in time and general-order in space for the scalar wave equation

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A stability formula for Lax-Wendroff methods with fourth-ord...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： jing-Bo Chen~1 ~1Key Laboratory of Petroleum Resources Research,institute of geology and geophysics,chinese academy of sciences,beijing,china.

Based on the formula for stability of finite-difference methods with second-order in time and general-order in space for the scalar wave equation,I obtain a stability formula for Lax-Wendroff methods with fourth-order in time and general-order in *** the formula for methods with second-order in time,this formula depends on two parameters:one parameter is related to the weights for approximations of second spatial derivatives;the other parameter is related to the weights for approximations of fourth spatial *** discretizing the mixed derivatives properly,the formula can be generalized to the case where the spacings in different directions are different. This formula can be useful in high-accuracy seismic modeling using the scalar wave equation on rectangular grids,which involves both high-order spatial discretizations and high-order temporal approximations.I also prove the instability of methods obtained by applying high-order finite-difference approximations directly to the second temporal derivative,and this result solves the"Bording’s conjecture."

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Multisymplectic Pseudospectral Discretizations for(3+1)-Dimensional Klein-Gordon Equation

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Multisymplectic Pseudospectral Discretizations for(3+1)-Dime...

中国科学院地质与地球物理研究所2008学术年会

作者： CHEN jing-Bo~+ and LIU Hong institute of geology and geophysics,chinese academy of sciences,P.O.Box 9825,beijing 100029,china

We explore the multisymplectic Fourier pseudospectral discretizations for the(3+1)-dimensional Klein-Gordon equation in this *** corresponding multisymplectic conservation laws are *** kinds of explicit symplectic int... 详细信息

关键词： multisymplectic pseudospectral (3+1)-dimensional Klein-Gordon equation

High-resolution carbon isotope record for the Paleocene-Eocene thermal maximum from the Nanyang Basin,Central china

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High-resolution carbon isotope record for the Paleocene-Eoce...

中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ZHU Min~(1,2*),ding zhongli~1,WANG Xu~1,CHEN ZuoLing~1,JIANG HanChao~3, DONG XinXin~1,JI JunLiang~4,TANG ZiHua~1 & LUO Pan~1 1 Key Laboratory of Cenozoic geology and Environment,institute of geology and geophysics,chinese academy of sciences,beijing 100029, china 2 The Graduate University of chinese academy of sciences,beijing 100049,china 3 State Key Laboratory of Earthquake Dynamics,institute of geology,china Earthquake Administration,beijing 100029,china 4 Key Laboratory of Biogeology and Environmental geology,Ministry of Education,china University of Geosciences,Wuhan 430074,china

The Paleocene-Eocene thermal maximum(PETM) was a transient episode of global warming,associated with massive atmospheric greenhouse gas input that occurred at the Paleocene/Eocene *** and isotope stratigraphic studies indicate that the PETM event is well documented in the marl deposits of the Yuhuangding section in the Nanyang Basin,Central china,with a carbon isotope negative excursion of～6.1‰within 19-m-thick marl *** is the highest resolution record of the PETM so far found in the *** PETM event was triggered within 2-cm-thick marl sediments,with a decrease ofδC (stable carbon isotope ratio) from -3.2‰to -5.2‰,suggesting a massive methane hydrate release for a transient period that was possibly caused by a catastrophic event.A comparison between marine and terrestrial records indicates a"Three-Phase Model"for the PETM *** there is a rapid negative excursion in theδC record,followed by a slowly decreasing trend,and then a gradual positive recovery,corresponding respectively to a rapid dissociation of oceanic methane hydrate,followed by a slow release of methane and then the consumption of the released methane.

关键词： PETM carbon isotope greenhouse gases Nanyang Basin

Microwave propagation in air drilling

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Petroleum Science 2010年第3期7卷 390-396页

作者： Meng Xiaofeng Chen Yijian Zhou jing Meng Yingfeng Physics Department Beijing Normal University Beijing 100875 China State Key Laboratory of Oil and Gas Reservoir geology and Exploitation Southwest Petroleum University Chengdu Sichuan 610500 China

This paper examines the feasibility in air drilling of transmitting down-hole signals by using microwaves. Firstly the basic theory of microwave propagation in the drill-pipe or casing was studied, including power loss, cutoff wavelength, and dust scattering. Theoretical analysis indicates that the microwave propagation distance in a cb214mm casing can easily reach 5,000 m. When the effect of dust particles is taken into account, the propagation distance decreases to 2,000 m. We conducted both laboratory experiments and field tests in casings commonly used in oil fields. The field tests show that the effective propagation distance of microwave in the casing is about 1,300 m. The experimental results do not match well with theoretical prediction, but are acceptable. In future commercial applications, by applying multiple relay amplifiers, the microwave propagation distance could be long enough for most drilling wells.

关键词： Microwave waveguide drill-pipe casing air drilling

Rock Mechanics and Rock Engineering in china:Developments and Current State-of-the-Art

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Rock Mechanics and Rock Engineering in China:Developments an...

作者： SUN Jun~1,WANG Si-jing~2 (1.Tongji University,Shanghai,200092,china 2.institute of geology,china academy of sciences,beijing 100029,china)

This paper presents the development and state of the art of rock mechanics and rock engineering in china,looking back at the history of development of rock mechanics and the main achievements in rock engineering (PartⅠ).Some large rock projects are introduced and aspects of near future progress and prospects are summarized(PartⅡ).(?) 2000 Elsevier Science *** rights reserved.

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