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Helium isotope investigation on magnetic reversal boundaries of loess-paleosol sequence at Luochuan, central chinese Loess Plateau

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chinese Science Bulletin 2007年第17期52卷 2407-2412页

作者： DU XueQing1,6, WANG YongHong2, REN JianGuo3, YE XianRen4.& LU HuaYu5,1 1 State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, chinese academy of Sciences, Xi’an 710075, china 2 College of Marine Geosciences, Ocean University of china, Qingdao 266003, china 3 National Natural Science Foundation of china, beijing 100085, china 4.Lanzhou Research Center for Petroleum and Natural Gas Resources, Institute of Geology and Geophysics, chinese academy of Sciences, Lanzhou 730000, china 5 Key Laboratory of Coast and Island Development, School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing 210093, china 6 Graduate University of chinese academy of Sciences, beijing 10004., china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of Sciences Beijing China College of Marine Geosciences Ocean University of China Qingdao China National Natural Science Foundation of china Beijing China Lanzhou Research Center for Petroleum and Natural Gas Resources Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China Key Laboratory of Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing China

Extraterrestrial particles have higher 3He/4.e ratios than those of terrestrial sediments ( > 100 Ra versus < 0.03 Ra, where Ra is the 3He/4.e ratio normalized to the atmospheric value of 1.4.10?6). The inter- planet... 详细信息

Extraterrestrial particles have higher 3He/4.e ratios than those of terrestrial sediments ( > 100 Ra versus 4.e ratio normalized to the atmospheric value of 1.4.10?6). The inter- planetary dust particles (IDPs), which are very rich in 3He, continuously bombard the Earth and can accumulate in deposits. IDPs sedimentation rate changes can significantly influence 3He concentration in the Earth surface sediments. Since IDPs are not easy to detect in terrestrial deposits, measuring helium isotopes is a helpful approach to examine changes in IDPs. Helium concentration and helium isotopic composition magnetic substances and the quartz particles were examined for helium concen- tration and helium isotopic ratio. Results show that the 3He/4.e ratio and the 3He concentrations of the magnetic substances are clearly higher than those of the bulk samples and the quartz particles, and, the 3He/4.e ratio of the extracted magnetic substances is also higher than that of the average level of the Earth’s crust. The higher helium content in the magnetic fractions can be explained by an influx of IDPs.

关键词：中国黄土高原古土壤氦同位素行星际尘埃颗粒反方向磁化

chinese Expert Consensus on Microvascular Protection Strategy During Emergency Percutaneous Coronary Intervention Therapy in Patients With ST-elevation Myocardial Infarction

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Cardiology Discovery 2024年第1期4卷 5-14页

作者： chinese Society of Cardiology,chinese Medical Association Editorial Board of chinese Journal of Cardiology Muwei Li Yabin Wang Yaling Han Yun Zhang Feng Cao 不详 Fuwai Central china Cardiovascular Hospital chinese People’s Liberation Army General Hospital General Hospital of Northern Theater Command Qilu Hospital of Shandong University

Microcirculatory dysfunction(CMD)typically occurs in patients with acute ST-segment elevation myocardial infarction during percutaneous coronary intervention,which is associated with more severe myocardial injury and a worse *** the advancement of intracoronary physiology and imaging technology,the prevention and therapeutic interventions of CMD have attracted more ***,relevant guidelines or consensus on CMD are lacking in *** current consensus summarizes the prevention and diagnostic strategies of emergency percutaneous coronary intervention-related CMD and gives suggestions to improve the prognosis of ST-segment elevation myocardial infarction patients based on evidence from recent clinical studies,guidelines,and consensus from international sources.

关键词： Myocardial infarction Microcirculation dysfunction Percutaneous coronary intervention

中国政治经济学年度发展报告（2023）（下）

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政治经济学评论 2024年第3期 90+207-208页

作者： Center for Studies of Contemporary Political Economy,Research Institute for 21st-Century Marxism,Nankai University·University of chinese academy of Social Science Center for Teaching and Research on Capital,Renmin University of china National Institute of Socialist Political Economy with chinese Characteristics,Renmin University of china 南开大学·中国社会科学院大学21世纪马克思主义研究院当代政治经济学研究中心中国人民大学《资本论》教学与研究中心中国人民大学全国中国特色社会主义政治经济学研究中心

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，...

编者按2023年，高质量发展扎实推进，新质生产力加快形成，我国经济总体回升向好，圆满实现发展主要预期目标。为针对性地破解经济恢复发展中的难题，聚焦推进中国式现代化进程中的重点、难点问题，中国政治经济学界开展系统深入研究，取得系列代表性成果。为准确刻画学界研究进展和轨迹，推动中国经济学理论体系的构建和完善，本刊精选议题如期奉上《中国政治经济学年度发展报告（2023）》。自2010年起，本刊连续十四年发布《中国政治经济学年度发展报告》，“年度发展报告”专栏已成为本刊标志性特色栏目。2023年报告聚焦12个专题，分为（上）（下）两篇，其中专题1—6于报告（上）篇刊登，专题7—12由报告（下）篇刊登。2023年报告（下）选题如下：

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Subspace Search Method for Quadratic Programming With BoxConstraints

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Journal of Computational Mathematics 1999年第3期17卷 307-314页

作者： Zi-luan Wei(ICMSEC, chinese academy of Sciences, beijing 100080, china) 中科院计算数学与科学工程计算所北京

A subspace search method for solving quadratic programming with box constraints is presented in this paper. The original problem is divided into many independent subproblem at an initial point, and a search direction is obtained by solving each of the subproblem, as well as a new iterative point is determined such that the value of objective function is decreasing. The convergence of the algorithm is proved under certain assumptions, and the numerical results are also given.

关键词： subspace search method quadratic programing matrix splitting

UNCONSTRAINED METHODS F0R GENERALIZED NONLINEAR COMPLEMENTARITY AND VARIATIONAL INEQUALITY PROBLEMS

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Journal of Computational Mathematics 1996年第2期14卷 99-107页

作者： J.M. Peng(LSEC Institute of Computational Mathematics and Scientific/engineering Cmputing,chinese academy of Sciences, beijing,{4.) 中科院计算数学与科学工程计算所北京

In this papert we construct unconstrained methods for the generalized nonlinearcomplementarity problem and variational inequalities. Properties of the correspon-dent unconstrained optimization problem are studied. We apply these methods tothe subproblems in trust region method, and study their interrelationships. Nu-merical results are also presented.

关键词： Math UNCONSTRAINED METHODS F0R GENERALIZED NONLINEAR COMPLEMENTARITY AND VARIATIONAL INEQUALITY PROBLEMS

FOURIER-LEGENDRE PSEUDOSPECTRAL METHOD FOR THE NAVIER-STOKES EQUATIONS

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Journal of Computational Mathematics 2000年第3期18卷 225-238页

作者： Jian Li (LSEC, Institute of Computational Mathematics and Scientific/engineering Computing, academy of Mathematics and System Sciences, chinese academy of Sciences, {4., 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京 100080

Constructs a Fourier-Legendre pseudospectral scheme for Navier-Stokes equations with semi-periodic boundary condition. Equation of the scheme; Estimation of errors; Numerical results.

关键词： Navier-Stokes equations Fourier-Legendre pseudospectral method error estimation

MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE-Ⅱ SUPERCONDUCTORS

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Journal of Computational Mathematics 1997年第4期15卷 365-384页

作者： Zhi-ming Chen (Institute of Mathematics, chinese academy of Sciences, beijing, china) 中科院数学所北京

In this paper we seek the solutions of the time dependent Ginzburg-Landau model for type-Ⅱ superconductors such that the associated physical observables are spatially periodic with respect to some lattice whose basic lattice cell is not necessarily rectangular. After appropriately foring the gange, the model can be formulated as a system of nonlinear parabolic partial differential equations with quasi-periodic boundary conditions. We first give some results concerning the existence, uniqueness and regularity of solutions and then we propose a semiimplicit finite element scheme solving the system of nonlinear partial dmerential equations and show the optimal error estimates both in the L2 and energy *** also report on some numerical results at the end of the paper.

关键词： Math QT MODELLING AND NUMERICAL SOLUTIONS OF A GAUGE PERIODIC TIME DEPENDENT GINZBURG-LANDAU MODEL FOR TYPE SUPERCONDUCTORS

Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

作者： HUANG Peng1,2, LI Anchun1, HU Ningjing2,3, FU Yongtao1& MA Zhibang4.1. Institute of Oceanology, chinese academy of Sciences, Qingdao 266071, china 2. Graduate School of the chinese academy of Sciences, beijing 100039, china 3. Institute of Soil Science, chinese academy of Sciences, Nanjing 210008, china 4. Institute of Geology and Geophysics, chinese academy of Sciences, beijing 100029, china Institute of Oceanology Chinese Academy of Sciences Qingdao China Graduate School of the chinese academy of Sciences Beijing China Institute of Soil Science Chinese Academy of Sciences Nanjing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

PRESENT SITUATION AND FUTURE PROSPECT OF APPLICATION OF TUNNELING MACHINE TO chinese UNDERGROUND engineering CONSTRUCTION

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岩石力学与工程学报 2003年第12期22卷 2071-2080页

作者： Qian Qihu (chinese academy of engineering, beijing 100857{4.) chinese academy of engineering 北京 100875

The application of tunneling machine to chinese underground engineering construction is outlined,and its future prospect is forecasted in the light of the requirements for chinese underground engineering construction ... 详细信息

关键词：隧道掘进机中国地下工程发展前景