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991.
Deconlinement phase transition and neutrino trapping in (proto)neutron star matter are investigated in a chiral hadronic model (also referred to as the FST model) for the hadronic phase (HP) and in the color-flavor-locked (CFL) quark model for the deconlined quark phase. We include a perturbative QCD correction parameter αs in the CFL quark matter equation of states. It is shown that the CFL quark core with K^0 condensation forms in neutron star matter with the large value of αs. If the small value of αs is taken, hyperons suppress the CFL quark phase and the liP is dominant in the high-density region of (proto)neutron star matter. Neutrino trapping makes the fraction of the CFL quark matter decrease compared with those without neutrino trapping. Moreover, increasing the QCD correction parameter as or decreasing the bag constant B and the strange quark mass ms can make the fraction of the CFL quark matter increase, simultaneously, the fraction of neutrino in protoneutron star matter increases, too. The maximum masses and the corresponding radii of (proto)neutron stars are not sensitive to the QCD correction parameter αs. 相似文献
992.
GAO Xiu-Yun LIN Mai-Mai DUAN Wen-Shan 《理论物理通讯》2008,49(2):482-484
By deriving a Korteweg-de Vries (KdV) equation for particular
dusty plasma, we find the existing regions of solitary waves. The regions
of both rarefactive and compressive solitary waves have also been given in
this paper for a two-temperature ions and a hot adiabatic dusty fluid,
where the dust charges can vary. 相似文献
993.
《浙江大学学报(理学版)》2009,36(4):F0003-F0003
《浙江大学学报(理学版)》是由浙江大学主办的自然科学类学术期刊。主要刊载数学与计算机科学、物理学、电子科学、化学与环境科学、生命科学、地球科学与城市科学、心理学等方面的最新研究成果。为保证刊物质量,并与国外检索性期刊要求接轨,根据《中国学术期刊(光盘版)》的最新要求和国家关于科技期刊标准的要求,结合本刊实际,制定本简则,请投稿者执行。 相似文献
994.
LIU Ping LOU Sen-Yue 《理论物理通讯》2009,51(1):27-34
The symmetries, symmetry reductions, and exact solutions of a coupled nonlinear Schrodinger (CNLS) equation derived from the governing system for atmospheric gravity waves are researched by means of classical Lie group approach in this paper. Calculation shows the CNLS equation is invariant under some Galilean transformations, scaling transformations, phase shifts, and space-time translations. Some ordinary differential equations are derived from the CNLS equation. Several exact solutions including envelope cnoidal waves, solitary waves and trigonometric function solutions for the CNLS equation are also obtained by making use of symmetries. 相似文献
995.
使用接触角测量和电化学技术研究了三相线界面区(TPB)宽度在分散液膜下金属腐蚀过程中的作用.研究发现,阴极极限电流和腐蚀电流密度随TPB宽度增加而线性增大,表明TPB宽度对气/液/固多相体系腐蚀过程具有重要影响.因此,可根据TPB宽度评价分散液膜厚度对大气腐蚀速率之影响. 相似文献
996.
Ladislav Ceniga 《Acta Mechanica Sinica》2010,26(1):101-106
The paper deals with analytical models of the elastic energy gradient Wsq representing an energy barrier. The energy barrier is a surface integral of the elastic energy density Wq. The elastic energy density is induced by thermal stresses acting in an isotropic spherical particle (q = p) with the radius R and in a cubic cell of an isotropic matrix (q = m). The spherical particle and the matrix are components of a multi-particle-matrix system representing a model system applicable to a real two-component material of a precipitation-matrix type. The multi-particle-matrix system thus consists of periodically distributed isotropic spherical particles and an isotropic infinite matrix. The infinite matrix is imaginarily divided into identical cubic cells with a central spherical particle in each of the cubic cells. The dimension d of the cubic cell then corresponds to an inter-particle distance. The parameters R, d along with the particle volume fraction v = v(R, d) as a function of R, d represent micro- structural characteristics of a real two-component material. The thermal stresses are investigated within the cubic cell, and accordingly are functions of the microstructural charac- teristics. The thermal stresses originate during a cooling pro- cess as a consequence of the difference am - ap in thermal expansion coefficients between the matrix and the particle, am and ap, respectively. The energy barrier Wsq is used for the determination of the thermal-stress induced strengthening aq. The strengthening represents resistance against com- pressive or tensile mechanical loading for am - ap 〉 0 or am - ap 〈 0. respectively. 相似文献
997.
《浙江大学学报(理学版)》2010,37(2):F0003-F0003
《浙江大学学报(理学版)》是由浙江大学主办的自然科学类学术期刊。主要刊载数学与计算机科学、物理学、电子科学、化学与环境科学、生命科学、地球科学与城市科学、心理学等方面的最新研究成果。为保证刊物质量,并与国外检索性期刊要求接轨, 相似文献
998.
《浙江大学学报(理学版)》2010,(6):I0002-I0002
《浙江大学学报(理学版)》创刊于1956年,前身为《杭州大学学报(自然科学版)》。系由浙江大学主办,国家教育部主管的自然科学类学术期刊。主要刊载数学与计算机科学、物理学、电子科学、化学与环境科学、生命科学、地球科学与城市科学、心理学等为主的具有较高学术水平和理论水平的理学类研究论文、研究简报等。年载文量150余篇。 相似文献
999.
大气制动期间探测器的气动特性和轨道计算 总被引:1,自引:0,他引:1
以NASA火星全球勘测(MGS)号探测器作为大气制动计算模型,应用DSMC方法模拟了探测器在大气制动期间的稀薄气体动力学特性,分析了不同来流密度情况下探测器的流场特性、气动特性的变化情况以及气体动力学系数的变化关系.并提出了气动力-气动热-轨道一体化计算模型,利用DSMC模拟技术以及经典动力学理论对大气制动轨道变化进行了计算和分析.研究结果表明:行星大气密度、探测器俯仰角、偏航角的变化对探测器的气动特性有重要影响,计算结果与文献中的结果表现出很好的一致性;气动力-气动热-轨道一体化计算可以模拟大气制动过程,模拟所得到的大气制动轨迹反映出较好的制动效果. 相似文献
1000.
WarrenMatthews LesCottrell 《高能物理与核物理计算国际会议公报》2001,(1):409-411
After less than a year of operation ,the BaBar experiment at SLAC has collected almost 100 million particle collision events in a database approaching 165TB.Around 20 TB of data has been exported via the Internet to the BaBar regional center at IN2P3 in Lyon,France,and around 40TB of simulated data has been imported from the Lawrence Livermore National Laboratory(LLNL),BaBar Collaborators plan to double data collection each year and export a third of the data to IN2P3.So within a few years the SLAC OC3 (155Mbps) connection will be fully utilized by file transfer to France alone.Upgrades to infrastructure is essential and detailed understanding of performance issues and the requirements for reliable high throughput transfers is critical.In this talk results from active and passive monitoring and direct measurements of throughput will be reviewed.Methods for achieving the ambitious requirements will be discussed. 相似文献