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Dynamically Exploring the QCD matter at Finite Temperatures and Densities:A Short Review

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Chinese Physics Letters 2021年第8期38卷 23-31页

作者： Shanjin Wu Chun shen Huichao Song Center for High Energy Physics Peking UniversityBeijing 100871China Department of Physics and State Key Laboratory of Nuclear Physics and Technology Peking UniversityBeijing 100871China Collaborative Innovation Center of Quantum matter Beijing 100871China Department of Physics and Astronomy Wayne State University DetroitMichigan 48201USA RIKEN BNL Research Center Brookhaven National Laboratory UptonNew York 11973USA

We provide a concise review on recent theory advancements towards full-fledged(3+1)D dynamical descriptions of relativistic nuclear collisions at finite baryon ***-ion collisions at different collision energies produce strongly coupled matter and probe the QCD phase transition at the crossover,critical point,and first-order phase transition *** frameworks provide a quantitative tool to extract properties of hot QCD matter and map fireballs to the QCD phase *** challenges are highlighted when confronting current theoretical frameworks with current and forthcoming experimental measurements from the RHIC beam energy scan programs.

关键词： density Dynamical collision

Optimal antiarrhythmic drug therapy for electrical storm

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The Journal of Biomedical Research 2015年第1期29卷 20-34页

作者： Dan Sorajja Thomas m.munger Win-Kuang shen Division of Cardiovascular Diseases Mayo Clinic Arizona

Electrical storm, defined as 3 or more separate episodes of ventricular tachycardia or ventricular fibrillation within 24 hours, carries significant morbidity and mortality. These unstable ventricular arrhythmias have been described with a variety of conditions including ischemic heart disease, structural heart disease, and genetic conditions. While implantable cardioverter defibrillator implantation and ablation may be indicated and required, anti- arrhythmic medication remains an important adjunctive therapy for these persons.

关键词： antiarrhythmic medication electrical storm ventricular tachycardia ventricular fibrillation

ON COmPLETE SPACE-LIKE SUBmANIFOLDS WITH PARALLEL mEAN CURVATURE VECTOR

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Chinese Annals of mathematics,Series B 1998年第3期19卷 369-380页

作者： shen YIBIING DONG YUXING Department of mathematics Hangzhou University Hangzhou 310028 China

Let m n be a complete space-like submanifold with parallel mean curvature vector in an indefinite space form N n+p p (c).A sharp estimate for the upper bound of the norm of the second fundamental form of m n is obtained. A generalization of this result to complete space-like hypersurfaces with constant mean curvature in a Lorentz manifold is given. moreover, harmonic Gauss maps of m n in N n+p p(c) in a generalized sense are considered.

关键词： Pseudo-Riemannian manifold Space-like submanifolds Parallel mean curvature vector Second fundamental form

Risk of shear failure and extensional failure around over-stressed excavations in brittle rock

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Journal of Rock mechanics and Geotechnical Engineering 2017年第2期9卷 210-225页

作者： Nick Barton Baotang shen Nick Barton&Associates OsloNorway CSIRO Energy BrisbaneAustralia

The authors investigate the failure modes surrounding over-stressed tunnels in *** lines of investigation are employed:failure in over-stressed three-dimensional(3D) models of tunnels bored under 3D stress,failure modes in two-dimensional(2D) numerical simulations of 1000 m and 2000 m deep tunnels using FRACOD,both in intact rock and in rock masses with one or two joint sets,and finally,observations in TBm(tunnel boring machine) tunnels in hard and medium hard massive *** reason for 'stress-induced' failure to initiate,when the assumed maximum tangential stress is approximately(0.4-0.5)σ_c(UCS,uniaxial compressive strength) in massive rock,is now known to be due to exceedance of a critical extensional strain which is generated by a Poisson's ratio ***,because similar 'stress/strength' failure limits are found in mining,nuclear waste research excavations,and deep road tunnels in Norway,one is easily misled into thinking of compressive stress induced *** of this,the empirical SRF(stress reduction factor in the Q-system) is set to accelerate as the estimated ratio σ_(θmax)/σ_c >> *** mining,similar 'stress/strength' ratios are used to suggest depth of *** reality behind the fracture initiation stress/strength ratio of '0.4' is actually because of combinations of familiar tensile and compressive strength ratios(such as 10) with Poisson's ratio(say0.25).We exceed the extensional strain limits and start to see acoustic emission(AE) when tangential stress σθ ≈ 0.4σc,due to simple *** combination of 2D theoretical FRACOD models and actual tunnelling suggests frequent initiation of failure by 'stable' extensional strain fracturing,but propagation in 'unstable' and therefore dynamic *** the case of very deep tunnels(and 3D physical simulations),compressive stresses may be too high for extensional strain fracturing,and shearing will dominate,both ahead of the face and following the *** shallower,the conc

关键词： Fracture propagation Tension Shear Poisson’s ratio Break-out Rock burst Deep tunnels FRACOD model

Generalization of CS condition

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Frontiers of mathematics in China 2017年第1期12卷 199-208页

作者： Liang shen Wenxi LI Department of mathematics Southeast University Nanjing 210096 China Department of mathematics and Physics Anhui University of Technology Ma'anshan 243002 China

Let R be an associative ring with identity. An R-module m is called an NCS module if l（m）∩y（m） = {0}, where l（m） and y（m） denote the set of all closed submodules and the set of all small submodules of m, respectively. It is clear that the NCS condition is a generalization of the well-known CS condition. Properties of the NCS conditions of modules and rings are explored in this article. In the end, it is proved that a ring R is right ∑-CS if and only if R is right perfect and right countably ∑-NCS. Recall that a ring R is called right ∑-CS if every direct sum of copies of RR is a CS module. And a ring R is called right countably ∑-NCS if every direct sum of countable copies of RR is an NCS module.

关键词： NCS modules NCS rings CS rings ∑-CS rings countably ∑-NCS rings

Diffusion behavior and distribution regulation of mgO in mgO-bearing pellets

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International Journal of minerals,metallurgy and materials 2016年第9期23卷 1011-1018页

作者： Qiang-jian Gao Yan-song shen Guo Wei Xin Jiang Feng-man shen School of metallurgy Northeastern University School of Chemical Engineering University of New South Wales

In this paper, the diffusion behavior between mgO and Fe2O3（the main iron oxide in pellets） is investigated using a diffusion couple method. In addition, the distribution regulation of mgO in mgO-bearing pellets is analyzed via pelletizing experiments. The results illustrate that mgO is prone to diffuse into Fe2O3 in the form of solid solution; the diffusion rate considered here is 13.64 μm·min^（-1）. most mgO content distributes in the iron phase instead of the slag phase. The mF phase {（mg（1-x）Fex）O·Fe2O3, x ≤ 1} is generated in the mgO-bearing pellets. However, the distribution of mgO in the radial direction of the pellets is inconsistent. The solid solution portion of mgO in the mF phase is larger in the outer layer of the pellets than in the inner layer. In this work, the approximate chemical composition of the mF phase in the outer layer of the pellets is {（mg（0.35-0.77）·Fe（0.65-0.23）） O·Fe2O3} and in the inner layer is {（mg（0.13-0.45）·Fe（0.87-0.55））O·Fe2O3}.

关键词： magnesia iron oxide ore pellets diffusion distribution

Thermoelectric characteristics of semiconductor minerals in earth's deep crust and their seismogenic significance

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Geoscience Frontiers 2022年第2期13卷 159-164页

作者： Shuhao Wang Junfeng shen m.Santosh Yuanyuan Li Cheng-Xue Yang Liangkun ma School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China Department of Earth Science University of AdelaideAdelaideSA 5005Australia

Geo-electric anomalies are generated during the process of stress accumulation and release associated with ***,the mechanism of these anomalies remains *** on the analysis of thermoelectric characteristics of semiconductor minerals of the earth’s deep crust such as graphite,ferrosilicon alloy,magnetite etc.,we perform finite element analysis to evaluate the principles governing the thermoelectric power generated by minerals and *** results show that graphite,ferrosilicon alloy and magnetite all exhibit Seebeck effect and can be *** the thermo-electric field can be enhanced with the activation temperature increases,the content of thermoelectric minerals increases,the size of aggregates increases,and the spacing of thermoelectric minerals grains *** processes would generate a similar thermal *** natural semiconductor minerals in this thermal field show a thermoelectric effect,forming a thermoelectric field that interferes with the background electric *** study indicates that thermoelectric effect may have an important influence on the formation of geoelectric field.

关键词： Natural semiconductor minerals Seebeck effects Geoelectric anomalies Earthquakes Deep crust

Geochemical constraints on the origin of Early Cretaceous alkaline intrusions and its tectonic implication,Sulu Orogenic Belt,Eastern North China Craton

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Acta Geochimica 2020年第5期39卷 616-641页

作者： shen Liu Caixia Feng Yan Fan Kairui Tai Tianjing Gao Ian m.Coulson State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi'an 710069China Solid Earth Studies Laboratory.Department of Geology University of Regina.ReginaSK S4S 0A2Canada

Post-orogenic alkaline intrusions from the Sulu Orogenic Belt of eastern North China Craton consist of A-type *** this study,we report U-Pb zircon ages,geochemical data,Sr-Nd-Pb,and zircon Hf isotopic data for these *** LA-ICP-mS U-Pb zircon analyses yield consistent ages ranging from 127.1±2.4 to 119.5±4.8 ma for four *** alkaline rocks are characterized by high total alkalis(K2 O+Na2 O=8.32-10.11 wt%),light rare-earth element enrichment,and heavy rare-earth element depletion,with a wide range(La/Yb)N values(20-48),moderate negative Eu anomalies(Eu/Eu*=0.50-0.74),enrichment in large-ion lithophile elements(LILEs,i.e.,Rb,Th,U and Pb),and depletion in Ba,Sr and high field strength elements(HFSEs,i.e.,Nb,Ta,and Ti),high(87Sr/86Sr)i ranging from 0.708 to 0.7089,low sNd(t)values from-19.4 to-16.8,(206Pb/204Pb)i=16.751-16.935,(207Pb/204Pb)i=15.381-15.535,(208-Pb/204Pb)i=37.472-37.838,negativeεHf(t)values between-21.3 and-25.7 for the magmatic zircons,and larger TDm2 model ages from 2.5 to 2.8 *** results suggest that the rocks were derived from a common enriched lithospheric mantle source that was metasomatized by foundered lower crustal eclogitic materials before magma ***,the geochemical and isotopic feature implies that the primary magma of these rocks originated through partial melting of ancient lithospheric mantle that was variably hybridized by melts derived from lower crust *** rocks in this study may have been generated by subsequent fractionation of potassium feldspar,plagioclase,ilmenite,and/or ***,negligible crustal contamination occurred during the diagenesis process.

关键词： Post-orogenic magmatism Alkaline rocks Contamination Sulu Orogenic Belt North China Craton

A REmAPPING mETHOD BASED ON mULTI-POINT FLUX CORNER TRANSPORT UPWIND ADVECTION ALGORITHm

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Journal of Computational mathematics 2013年第6期31卷 592-619页

作者： Zhijun shen Guixia Lv National Key Laboratory of Science and Technology on Computational Physics Institute of Applied Physics and Computational Mathematics P.O.Box 8009-26 Beijing 100088 China Center for Applied Physics and Technology HEDPS Peking University Beijing 100871 China

A local remapping algorithm for scalar function on quadrilateral meshes is described. The remapper from a distorted grid to a rezoned grid is usually regarded as a conservative interpolation problem. The present paper introduces a pseudo time to transform the interpolation into an initial value problem on a moving grid, and construct a moving mesh method to solve it. The new feature of the algorithm is the introduction of multi- point information on each edge, which leads to the numerical flux consistent with grid node motion. During the procedure of deriving scheme, we illustrate a framework about how the algorithms on a rectangular mesh are easily generated to those on a moving mesh. The basic ideas include：（i） introducing coordinate transformation, which maps the irregular domain in physical space to a perfectly regular computational domain, and （ii） deriving finite volume methods in the physical domain, which can be viewed as a discretization of the transformed equation. The resulting scheme is second-order accurate, conservative and monotonicity preserving. Numerical examples are carried out to show the good performance of ore＂ schemes.

关键词： Remapping Advection multi-point flux Coordinate transformation Geometric conservation law.