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Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. SUN Hongwei1, GUO Min1, WANG Yanfang1, LIU Hui1, ZHAO Qingyun3, SUN Xinmin3, ZHAO Wenjun3 & CHENG Huansheng4.1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 4.0052.{2. 2. department of physics, beijing {4. University, beijing 100875,{2. 3. Institute of Cultural Relic and Archaeology of Henan Province, Zhengzhou 4.0000,{2. 4. Institute of Modern physics, Fudan University, Shanghai 2.04.3,{2. Faculty of Physical Engineering Zhengzhou University Zhengzhou China department of physics Beijing Normal University Beijing China Institute of Cultural Relic and Archaeology of Henan Province Zhengzhou China Institute of Modern physics Fudan University Shanghai China

34.samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.

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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 {2. University,Changsha 4.0081,china~2.department of physics,beijing {2. 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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Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. department of Mathematics, beijing {2. University, beijing 100875,{4. 2. department of Mathematics, Neijiang Teacher's College, Neijiang 64.112.{4.) beijing normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

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

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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,{2. normal University,{2. {4.,china 2.Business Office,{2. Planetarium,{2. 10004.,china 3 Center for High Energy physics,Peking University,{2. 100871,china 4.department of physics,Dezhou University,Dezhou 2.302.,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＋0.19-0.2. and ΩM = 0.32.0.12.0.06 at the 1σ confidence *** we assume a Gaussian prior of ΩM = 0.2. ± 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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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, {2. normal University, beijing 100875 china ~3 Key Laboratory for Molecular Biology and Gene Engineering Drugs of {2., 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 2.2.x 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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Eigenvalues, inequalities and ergodic theory

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Chinese Science Bulletin 2000年第9期45卷 769-774页

作者： CHEN Mufadepartment of Mathematics, beijing {2. University, beijing 100875,{4. department of Mathematics Beijing Normal University Beijing China

This paper surveys the main results obtained during the period 1992.1999 on three aspects mentioned in the title. The first result is a new and general variational formula for the lower bound of spectral gap (i.e. the first non-trivial eigenvalue) of elliptic operators in Euclidean space, Laplacian on Riemannian manifolds or Markov chains (?). Here, a probabilistic method -coupling method is adopted. The new formula is a dual of the classical variational formula. The last formula is actually equivalent to Poincare inequality. To which, there are closely related logarithmic Sobolev inequality, Nash inequality, Liggett inequality and so on. These inequalities are treated in a unified way by using Cheeger’s method which comes from Riemannian geometry. This consists of ?2. The results on these two aspects are mainly completed by the author joint with F. Y. Wang. Furthermore, a diagram of the inequalities and the traditional three types of ergodicity is presented (?3). The diagram extends the ergodic

关键词： eigenvalue inequality ergodic theory Markov process.

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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 {2. University, beijing 100875,{4. 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 2.2.5 μmol/L. CHA administration (10 mg/kg, ig×7 d) significantly enhanced the mac- rophage functions in normal mice. CHA (70.6, 1{2..2. and 2.2.5 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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Theoretical studies on the mechanism of the thermal decarboxylation and decarbonylation of a number of α-keto-acids

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Chinese Journal of Chemistry 1995年第6期13卷 487-492页

作者： CHEN,Li-Tao CHEN,Guang-Ju FU,Xiao-YuanChemistry department,beijing {2. University,beijing {4.,china Chemistry department Beijing Normal University Beijing 100875 China

Both processes of decarboxylation and decarbonylation of a number of acids including RCOCO2.,R=H,CH3,CH2.,CF3,CH=CH2.Ph,OH have been studied by semi-empirical MO theory AMI method to verify the reaction mechanism of each process and the effect of different substituents on *** calculated results are consistent with the experimental reports and can be summed up as follows:(1) The decarboxylation of these acids to form aldehydes and carbon dioxide is concerted and takes place through a 4.membered ring transition state in which a partial negative charge develops on the carbon of the α-carbonyl group,so that the inductive effect of some substituents is favourable for this process.(2. Their decarbonylation into carboxylic acids and carbon monoxide however is the attack of the OH on the carbon of the alkyl portion of the acid,forming a 3-membered ring transition state.(3) The activation energy of decarbonylation is lower than that of decarboxylation,since oxygen is more nucleophilic than hydrogen and also the strong OH bond need not to be broken.

关键词： Decarboxylation decarbonylation a-keto-acid

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Coupling, spectral gap and related topics (Ⅱ)

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Chinese Science Bulletin 1997年第18期42卷 1409-1416页

作者： CHEN Muf adepartment of Mathematics, beijing {2. University, beijing 100875,{4. department of Mathematics Beijing Normal University Beijing China

THIS is the second one of a series of three reviews. The ideas introduced in the last review are used to study the estimate of spectral gap and four classes of typical eigenvalue problems on manifolds. The comparison ... 详细信息

关键词： diffusions manifold Markov chains spectral gap couplings.

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Anomalous magnetotransport in LaMn_(1-x)Te_xO_3

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Science china(physics,Mechanics & Astronomy) 2009年第7期52卷 987-992页

作者： TAN GuoTai1,2. CHEN ZhengHao3 & ZHANG XiaoZhong4.5 1 Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education, Institute of Low Energy Nuclear physics, {2. normal University, beijing 100875,{4. 2.{2. Radiation Center, beijing 100875,{4. 3 Laboratory of Optical physics, Institute of physics, Chinese Academy of Sciences, {2. 100080,{4. 4.Key Laboratory of Advanced Materials of the Ministry of Education, department of Materials Science and Engineering, Tsinghua University, {2. 100084.{4. 5 {2. National Center for Electron Microscopy, Tsinghua University, {2. 100084.{4. Key Laboratory of Beam Technology & Materials Modification of the Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing China beijing Radiation Center Beijing China Laboratory of Optical physics Institute of Physics Chinese Academy of Sciences Beijing China Key Laboratory of Advanced Materials of the Ministry of Education Department of Materials Science and Engineering Tsinghua University Beijing China beijing National Center for Electron Microscopy Tsinghua University Beijing China

The LaMn1-xTexO3+δ (x=0.1, 0.2. 0.3) were synthesized using solid-state reaction method for the first time. X-ray photoemission spectrum (XPS) shows that in the samples the Te ions have a valence of Te4., and Mn3+ ions are partly converted into Mn2. and Mn4. due to the excess oxygen and Te doping. The magnetotransport associated with Mn2., Mn3+ and Mn4. was investigated. The experimental results show that the samples are insulator at 0 T when the amount of Mn3+ is much larger or less than the sum of Mn2. and Mn4.; by contrast, the samples display metal to insulator transition with increasing temperature when the amount of Mn3+ is close to the sum of Mn2. and Mn4.. These anomalous magnetotransport behaviors were analyzed in the frame of the double-exchange (DE) mechanism.

关键词： colossal magnetoresistance La-Te-Mn-O magnetotransport

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