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Constraints on smoothness parameter and dark energy using observational H(z) data

Research in Astronomy and Astrophysics 2011年第2期11卷 125-136页

作者： Hao-Ran Yu1,Tian Lan1,Hao-Yi Wan2,Tong-Jie Zhang1,3 and Bao-Quan Wang4.1 department of Astronomy,beijing normal university,beijing 100875,China 2 Business Office,beijing Planetarium,beijing 10004.,China 3 Center for High Energy physics,Peking university,beijing 100871,China 4.department of physics,Dezhou university,Dezhou 253023,China department of Astronomy Beijing Normal University Beijing 100875 China Business Office Beijing Planetarium Beijing 100044 China Center for High Energy physics Peking University Beijing 100871 China department of physics Dezhou University Dezhou 253023 China

With large-scale homogeneity,the universe is locally inhomogeneous,clustering into stars,galaxies and larger *** property is described by the smoothness parameter α which is defined as the proportion of matter in the form of intergalactic *** we consider the inhomogeneities over a small scale,there should be modifications of the cosmological distances compared to a homogenous *** and Roeder developed a second-order ordinary differential equation（D-R equation） that describes the angular diameter distance-redshift relation for inhomogeneous cosmological ***,we may obtain the D-R equation for observational H（z） data（OHD）.The density-parameter ΩM,the state of dark energy ω,and the smoothness-parameter α are constrained by a set of OHD in a spatially flat XCDM universe as well as a spatially flat XCDM *** using a χ2 minimization method,we get α = 0.81＋0.19-0.20 and ΩM = 0.32＋0.12-0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.26 ± 0.1,we get α = 0.93＋0.07-0.19 and ΩM = 0.31＋*** the XCDM model,α is constrained to α≥ 0.80 but ω is weakly constrained around-1,where ω describes the equation of state of the dark energy（pX = ωρX）.We conclude that OHD constrains the smoothness parameter more effectively than the data of SNe Ia and compact radio sources.

关键词： cosmology -- dark energy -- cosmological parameters

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Nano-Structure Observed in Highly Doped Silicon Crystalline

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Journal of Materials Science & Technology 1993年第3期9卷 232-234页

作者： Zhiheng LU department of physics,beijing normal {4.,beijing,100875,ChinaDachan WANG Yan LUO Institute of Low Energy Nuclear physics,beijing normal {4.,beijing,100875,China

It was reported that due to the non-linear electrical phenomena,the super-saturated arsenic in silicon single crystalline precipitates during post processing at low temperatures to form different *** structure with sp... 详细信息

关键词： nano-structure silicon semiconductor materials

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Bell States and Two-Qubit Logic Gate with Superconducting Charge Qubits Coupling to a Nanomechanical Resonator

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Communications in Theoretical physics 2007年第12期48卷 999-1002页

作者： LIAO Jie-Qiao~1 and WANG Xin-Wen~(2,3)~1 department of physics,Hunan normal university,Changsha 4.0081,China~2 department of physics,beijing normal university,beijing 100875,China~3 department of Electronic Engineering and physics,Hunan university of Science and Engineering,Yongzhou 4.5100,China department of physics Hunan Normal University Changsha 410081 China department of physics Beijing Normal University Beijing 100875 China department of Electronic Engineering and physics Hunan University of Science and Engineering Yongzhou 425100 China

We propose a scheme for generating Bell states involving two SQUID-based charge qubits by coupling themto a nanomechanical *** also show that it is possible to implement a two-qubit logic gate between the twocharge qu... 详细信息

关键词： Bell states superconducting charge qubit two-qubit logic gate nanomechanical resonator

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Cytotoxicity, apoptosis induction, and mitotic arrest by a novel podophyllotoxin glucoside, 4.PG, in tumor cells

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Acta Pharmacologica Sinica 2005年第8期26卷 1000-1008页

作者： Yi-lin QI~(2,4., Fan LIAO~(2,4., Chang-qi ZHAO~2, Yong-da LIN~2, Ming-xue ZUO~(2,3,5) ~2 College of Life Sciences, beijing normal university, beijing 100875 China ~3 Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing, beijing 100875, China College of Life Sciences Beijing Normal University Beijing China Key Laboratory for Molecular Biology and Gene Engineering Drugs of beijing Beijing China

Aim: To define the in vitro cytotoxic activities of 4.demethyl-picropodophyllotoxin 7'-O-β-D-glucopyranoside （4.PG）, a new podophyllotoxin glucoside. Methods: Antiproliferation activity was measured in several tumor cell lines by using the microculture tetrazolium MTT assays. Cell cycle distribution was analyzed using flow cytometry and mitosis index assays. Furthermore, transmission electron microscopy, TUNEL, DNA agarose electrophoresis, and activated caspase-3 were used to analyze the induction of apoptotic cell death. Moreover, intracellular changes in the cytoskeleton were detected using immunocytochemistry. Results: 4.PG effectively inhibited the proliferation of cancer cells （HeLa, CNE, SH-SY5Y, and K562 cell lines）. For the K562 cell line, the antiproliferation effect of 4.PG was much more potent than that of etoposide (IC50value: 7.79x10（-9） mol/L for 4.PG vs 2.23x 10（-5） mol/L for etoposide). Further, 4.PG blocked the cell cycle in the mitotic phase. The induction of apoptosis and elevated levels of activated caspase-3 were confirmed in cells treated with 4.PG. The microtubule skeleton of HeLa cells was disrupted immediately after treatment with 4.PG. Conclusion: The cytotoxicity of 4.PG is due to its inhibition of the microtubule assembly of cancer cells at a low concentration, thus inducing apoptosis. These properties qualify 4.PG to be a potential antitumor drug.

关键词： 4.demethyl-picropodophyllotoxin 7’-O-β-D-glucopyranoside podophyllotoxin flow cytometry microtubulin apoptosis

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Multiparty quantum secret sharing of classical and quantum messages

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Progress in Natural Science:Materials International 2007年第1期17卷 26-31页

作者： CHEN Pan, DENG Fuguo and LONG Guilu ( Key Laboratory for Quantum Information and Measurements, and department of physics, Tsinghua university, beijing 100084. China Key Laboratory of Beam Technology and Material Modification, MOE, Institute of Low Energy Nuclear physics, and department of Material Science and Engineering, beijing normal university, beijing 100875, China beijing Radiation Center, beijing 100875, China Key Laboratory for Atomic and Molecular Nano-Sciences, Tsinghua university, beijing 100084. China) Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China Key Laboratory of Beam Technology and Material Modification Beijing Normal University Beijing 100875 China Institute of Low Energy Nuclear physics Department of Material Science and Engineering Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China Key Laboratory for Atomic and Molecular Nano-Sciences Tsinghua University Beijing 100084 China

A scheme for multiparty quantum secret sharing of classical and quantum messages is proposed by using entanglement swapping. This scheme can distribute not only the classical information but also the quantum informati... 详细信息

关键词： quantum secret sharing classical message quantum message EPR pair.

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Central limit theorem for the occupation time of catalyticsuper-Brownian motion

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Chinese Science Bulletin 1998年第24期43卷 2035-2040页

作者： HONG Wenming department of Mathematics, beijing normal university, beijing 100875, China Corresponding address: Institute of Mathematics, Shantou university, Shantou 515063, China department of Mathematics Beijing Normal University Beijing China

The catalytic super_Brownian motion has been considered. If both the catalytic medium process Q and CSBM started with Lebesgue measure λ, the central limit theorem for occupation time of CSBM has been obtained in dim... 详细信息

关键词： branching rate functional Brownian collision local time catalytic super_Brownian motion occupation time central limit theorem.

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Effects of chlorogenic acid, an active compound activating calcineurin, purified from Flos Lonicerae on macrophage

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Acta Pharmacologica Sinica 2004年第12期25卷 119-123页

作者： He-zhen WU, Jing LUO, Yan-xia YIN, Qun WEI2 department of Biochemistry and Molecular Biology, beijing normal university, beijing 100875, China department of Biochemistry and Molecular Biology Beijing Normal University 北京 100875

AIM: To investigate the activation of chlorogenic acid (CHA) purified from Flos Lonicerae to calcineurin and its effects on macrophage functions in vivo and in vitro. METHODS: According to the screening results that Flos Lonicerae could activate calcineurin, the active component which could activate calcineurin was purified from Flos Lonicerae by column chromatography on silica gel and identified as CHA. The activation of CHA on calcineurin had been validated with both p-NPP and P-labeled RII peptide as the substrates. The clearance of charcoal particles in 32 normal mice and the cytotoxicity of U937 to MCF-7 were used together to determine the effects of CHA on macrophage functions. RESULTS: CHA could activate calcineurin, and the concentration of CHA on maximal activating calcineurin was 282.5 μmol/L. CHA administration (10 mg/kg, ig×7 d) significantly enhanced the mac- rophage functions in normal mice. CHA (70.6, 14..2, and 282.5 μmol/L) obviously increased the cytotoxicity of U937 to MCF-7. CONCLUSION: CHA could activate calcineurin and enhance the macrophage functions in vivo and in vitro, and its functions in vivo may be realized via the signal pathways of calcineurin.

关键词： calcineurin macrophage chlorogenic acid Flos Lonicerae

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Proof of inseparable prime C~*-algebras A with RR(A)=0 being primitive C~*-algebras

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Chinese Science Bulletin 1999年第8期44卷 688-690页

作者： ZHANG Lunchuan and MA Jipudepartment of Mathematics , beijing normal university , beijing 100875, China department of Mathematics , Nanjing {4., Nanjing 210093, China department of Mathematics Beijing Normal University Beijing China department of Mathematics Nanjing University Nanjing China

First, that prime C~* -algebras with countable primitive ideals are all primitive C*-algebras is proved. Then the proof that prime C~* -algebras with property RR(A) = 0 are all primitive C~*-algebras is given.

关键词： prime C~*-algebras primitive C~*-algebras hereditary C~*-algebras open projection and close projection.

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Enhanced Electron Transfer for Hemoglobin in 2C_(12)N^+PVS-Composite Films Modified on Pyrolytic Graphite Electrodes

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Chinese Chemical Letters 2000年第8期11卷 719-720页

作者： Yu Jiao HU, Ying Lin ZHOU, Yong Huai ZENG, Nai Fei HU (department of Chemistry, beijing normal university, beijing 100875) department of Chemistry Beijing Normal University Beijing 100875 China

Stable thin films made from polyionic complex 2C12N+PVS- with incorporated Hb on PG electrodes were characterized by electrochemistry. The electron transfer between Hb and PG electrodes was greatly facilitated in microenvironment of 2C12N+PVS- films. The Hb-2C12N+PVS-films could be used to catalytically reduce trichloroacetic acid.

关键词： Hemoglobin poly(vinyl sulfate) didodecyldimethylammonium surfactant-polymer composite films electrochemistry electrocatalysis.

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THEORETICAL　STUDIES　ON　THE　CYCLOADDITION　REACTION　OF　FLUOROKETENE　WITH　ETHYLIDENIMINE

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Chinese Chemical Letters 1995年第4期6卷 311-314页

作者： Zhen Feng XU De Cai FANG Xiao Yuan FU(department of Chemistry, beijing normal university, beijing, 100875) beijing normal Univ Dept Chem Beijing 100875 Peoples R China

The stereospecific rule of the cycloaddition reaction of ketene and imine has been treated theoretically in this Paper. By comparing the barrier heights, it can be seen that for trans imine the reaction will give cis ... 详细信息

关键词：颍

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