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Moderate deviation for super-Brownian motion with immigration

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science china Mathematics 2004年第3期47卷 440-452页

作者： ZHANG Mei department of Mathematics, beijing normal university, beijing 100875, china department of Mathematics, The Central university of Finance and Economics, beijing 100081, china 1. department of Mathematics Beijing Normal University 100875 Beijing China 2. department of Mathematics The Central University of Finance and Economics 100081 Beijing China

We prove a moderate deviation principle for a super-Brownian motion with immigration of all dimensions, and consequently fill the gap between the central limit theorem and large deviation principle.

关键词： moderate deviation principle super-Brownian motion with immigration large deviation principle evolution equation

Presenting degenerate Ringel-Hall algebras of type B

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science china Mathematics 2012年第5期55卷 949-960页

作者： FAN LiJuan1 & ZHAO ZhongHua2,1department of Mathematics,beijing normal university,beijing 100875,china 2department of Mathematics and Computer science,School of science,beijing university of Chemical Technology,beijing 100029,china 1. department of Mathematics Beijing Normal University Beijing 100875 China2. Department of Mathematics and Computer Science School of Science Beijing University of Chemical Technology Beijing 100029 China

We give a presentation for the degenerate Ringel-Hall algebras of type B by studying the corresponding generic extension monoid *** an application,it is shown that the degenerate Ringel-Hall algebras of type B admit m... 详细信息

关键词： degenerate Ringel-Hall algebras generic extension monoid algebras Auslander-Reiten quivers Frobenius morphism

EFFECT OF La_2O_3 ON THE RECRYSTALLIZATION OF MOLYBDENUM WIRES

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Acta Metallurgica Sinica(English Letters) 1996年第2期9卷 94-98页

作者： ZHANG Jiuxing ZHOU Meiling LIU Danmin ZUO Tieyong(department of materials science and engineering,beijing Polytechnic university,beijing 100022,china) beijing Polytechnic Univ Beijing China

The recrystallization behavior of Mo wires doped with various contents of La2O3,which were prepared by powder metallurgy method,was investigated using TEM and SEM in *** is shown that the recrystallization temperature and recrystallized microstructure of Mo-La2O3 wires are strongly dependent on the La2O3 *** interlocked large grain structure is formed in Mo-La2O3 wires with contents of 0.2-0.4 wt% La2O3,on the other hand,Mo─La2O3 wires containing less than 0.1 or more than 0.8 wt% La2O3 show equiaxed grain *** reason for this is the difference between the longitudinal interparticle spacing and the transverse spacing of La2O3 particles in various Mo-La2O3 wires,which was observed by using TEM.

关键词： molybdenum wire La_2O_3 recrystallization

MEAM Potential with Angular Dependence for TiAl

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Rare Metals 2001年第1期20卷 13-17页

作者： Xiaodong Ni, Xitao Wang, Guoliang Chen (Physics department, university of science and Technology beijing, beijing 100083, china State Key Laboratory for Advanced Metals and materials, university of science and Technology beijing, beijing 100083, china) Univ Sci & Technol beijing Dept Phys Beijing 100083 Peoples R China Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

The modified embedded atom method (MEAM) is an empirical extension of the embedded atom method (EAM) that includes angular forces. By fitted to the lattice constants, the cohesive energy, the APE (anti-phase boundary) energy, and the vacancy formation energy of TiAl, an accurate MEAM potential is obtained for the TiAl system with L10 structure. The calculation results of the properties of TiAl are in good agreement with experiments and the results of first principle (F.P.) calculations.

关键词： embedded atom method TiAl alloy angular dependence potential intermetallics

APPLICATION OF MOLECULAR ORBITAL THEORY TO ANALYSIS OF PHASE STABILITY FOR ALLOYS

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Acta Metallurgica Sinica(English Letters) 1993年第3期6卷 145-152页

作者： YIN Hong TAO Kun PAN Jinsheng LI Hengde Tsinghua university,beijing,china professor.department of materials science and engineering,Tsinghua university,beijing 100084,china Tsinghua Univ Beijing China

The critical _d vahues ( _ ) of the γ/(γ+σ).γ/(γ+μ) and γ/(γ+γ') phase boundaries in some ternar alloy phase diagrams at various temperatures are calculated by averaging the _d values of sererai selected characteristic points at the phase *** equations for the temperature dependence of the critical _d of γ/(γ+σ).γ/(γ+μ) and γ/(γ+γ') phase boundaries are *** accuracy of the analysis is discussed in detail. It is found for the first time that the average value of the bond order _ at the phase boundaries ts also approximatelr a constant and therefore a critical average bond order _ like - can be introduced for the analysts of phase stability

关键词： molecular orbital theory allov phase stabilitv

Constraints on Cardassian universe from Gamma ray bursts

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science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1720-1725页

作者： WANG TaiShan1 & LIANG Nan2 1 department of Physics & Center for Astrophysics,Tsinghua university,beijing 100084,china 2 department of Astronomy,beijing normal university,beijing 100875,china 1. department of Physics & Center for Astrophysics Tsinghua University Beijing 100084 China2. Department of Astronomy Beijing Normal University Beijing 100875 China

Constraints on the original Cardassian model and the modified polytropic Cardassian model are examined from the recently derived 42 gamma-ray bursts(GRBs) data calibrated with the method that can avoid the circularity *** results show that GRBs can be an optional observation to constrain the Cardassian *** the GRBs data with the newly de-rived size of baryonic acoustic oscillation peak from the Sloan Digital Sky Survey(SDSS),and the position of the first acoustic peak of the Cosmic Microwave Background radiation(CMB) from Wilkinson Microwave Anisotropy Probe(WMAP),we find Ωm0=0.27+0.02-0.02,n=0.06+0.07-0.08(1σ) for the original Cardassian model,and Ωm0=0.27+0.23-0.02,n=-0.09+0.23-1.91,β=0.82+2.10-0.62(1σ) for the modified polytropic Cardassian model.

关键词： Cardassian Gamma ray burst Cosmic Microwave Background baryonic acoustic oscillation

Effects of PKCa antisense RNA on human breast cancer cell proliferation and expression of cyclinD1 and CDK4

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Chinese science Bulletin 1999年第12期44卷 1110-1114页

作者： SANG Jianli WANG YongchaoLaboratory of Cell Biology , department of Biology, beijing normal university, beijing 100875 , china Laboratory of Cell Biology Department of Biology Beijing Normal University Beijing China

The role of PKCα in human breast cancer cell proliferation and expression of cyclinD1 and CDK4 has been investigated using inhibition of PKCα expression by its antisense RNA. When PKCα expression was inhibited the rate of cell proliferation decreased apparently and the levels of cyclinD1 and CDK4 mRNA were lower than the control. The results showed that PKCα, a key member of signal transduction system, played an important role in human breast cancer cell proliferation and had a close relationship with expression of cyclinD1 and CDK4 which control start of cell cycle.

关键词： breast cancer PKCα cell proliferation cyclinD1 CDK4.

Numerical Simulation of Shrinkage Cavity Formation in Spheroidal Graphite Iron Castings Based on Micro Modeling

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International Journal of Minerals,Metallurgy and materials 1998年第1期12卷 9-12页

作者： Wenzhen Li Baicheng Liu Shantong Jin (Metallurgy engineering School, university of science and Technology beijing, beijing 100083, china)(department of Mechanical engineering, Tsinghua university, beijing 100084, china) Metallurgy engineering School University of Science and Technology Beijing Beijing 100083 China department of Mechanical engineering Tsinghua University Beijing 100084 China

A micro-modeling method (MM) for the quantitative prediction of the shrinkage cavity formation in SGiron castings is proposed. The mathematical models describing the volume changes during the solidification ofspheroidal graphite cast iron are established based on the models of solidification kinetics. The shrinkage cavityformation of T-shaped SG iron castings is calculated with MM method. The calculated results are compared with theexperimental results. It is shown that the predicted size, shape and distribution of shrinkage cavity by MM methodare in good agreement with the measured results.

关键词： solidification shrinkage numerical simulation micro modeling spheroidal graphite cast iron

C^(18)O Observations of the Dark Molecular Cloud L134 and Gas Depletion onto Dust

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Chinese Journal of Astronomy and Astrophysics 2005年第2期5卷 144-150页

作者： Xin-Jie Mao and Xiao-Xia Sun department of Astronomy, beijing normal university, beijing 100875 maoxj@*** department of Astronomy Beijing Normal University Beijing 100875

We map the dark molecular cloud core of L134 in the C^(18)O (J = 1 - 0)emission line using the PMO 13.7m telescope, and present a contour map of integrated intensity ofC^(18)O (J = 1 - 0) emission. The C^(18)O cloud is inside the distribution of extinction A_B, thevisual extinction of blue light, as well as inside the ^(13)CO cloud in the L134 region. Thedepletion factors in this C^(18)O cloud are generally greater than unity, which means there is gasdepletion onto dust. Since only a minimum A_B - 9.7 mag is available, and our observations measureboth undepleted and depleted regions along the line of sight, the depletion factors could verylikely be larger in the central core than the calculated value. So we conclude that depletion doesoccur in the bulk of the C^(18)O cloud through a comparison between the C^(18)O and blue extinctionmaps in the L134 region. There is no direct evidence as yet for star formation in L134, and so coreson the verge of collapse will not be visible in CO and other gas molecules.

关键词： ISM: clouds ISM: individual (L134) ISM: molecules ISM: extinction