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Charge order and spin order in Nd_(0.5)Sr_(0.5)Mn_(1.x)(Ga_x, Ti_x)O_3 system

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Science china({1.,Mechanics & Astronomy) 2007年第3期50卷 294-302页

作者： REN QingBao1.2, ZHU WeiTing1. hong Bo{1. ZHANG YuHeng2 1.department of physics, lishui university, lishui 32.000, china 2 National High Magnetic Field laboratory, university of Science and Technology of china, Hefei 230026, china 1. department of {1. Lishui University Lishui 323000 China 2. National High Magnetic Field laboratory University of Science and Technology of China Hefei 230026 China

Magnetic properties of Nd_(0.5)Sr_(0.5)Mn_(1.x)(Ga_x, Ti_x)O_3 system (0.04≤x≤0.4) were inves- tigated through magnetization and electron spin resonance (ESR) measurements. It was observed that a small amount of Ti substitution for Mn will destroy the charge-ordering (CO) phase completely and induce the cluster-spin-glass phase in the system, which displays a procedure of collapse of CO and of an enhancement of spin ordering (SO) phase. In contrast, the Ga substitution for Mn induces a melt- ing of CO phase in the system. It was observed that with substitution the CO phase is suppressed gradually and the remanent CO phase is retained all the while, and withal, there is a co-existence of AFM CO phase and FM SO at low temperature. In addition, an abrupt rise of magnetization was observed in M-T curves. We attributed this abnormal phenomenon to a transition from canted AFM SO to FM SO in CO region.

关键词： charge ordering spin ordering antiferromagnetic transition

latest cosmological constraints on Cardassian expansion models including the updated gamma-ray bursts

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Research in Astronomy and Astrophysics 2011年第9期11卷 1019-1030页

作者： Nan liang Pu-Xun Wu Zong-hong Zhu department of Astronomy Beijing Normal University Beijing 100875 China Center for High Energy physics Peking University Beijing 100871 China Center of Nonlinear Science and department of {1. Ningbo University Ningbo 315211 China

We constrain the Cardassian expansion models from the latest observa- tions, including the updated Gamma-ray bursts （GRBs）, which are calibrated using a cosmology independent method from the Union2 compilation of type Ia supernovae （SNe Ia）. By combining the GRB data with the joint observations from the Union2 SNe Ia set, along with the results from the Cosmic Microwave Background radia- tion observation from the seven-year Wilkinson Microwave Anisotropy Probe and the baryonic acoustic oscillation observation galaxy sample from the spectroscopic Sloan Digital Sky Survey Data Release. we find significant constraints on the model oarameters of the original Cardassian model ΩM0=0.282-0.01.^0.01.,n=0.03-0.05^＋0.05 and n=-0.1.-3.26^＋0.25,β=0.76-0.58^＋0.34 of the modified polytropic Cardassian model, which are consistent with the ACDM model in a l-or confidence region. From the reconstruction of the deceleration parameter q（z） in Cardassian models, we obtain the transition redshift ZT = 0.73 ± 0.04 for the original Cardassian model and ZT = 0.68 ± 0.04 for the modified polytropic Cardassian model.

关键词： gamma-rays bursts -- cosmology cosmological parameters

Variation of reactivity of particulate and sedimentary organic matter along the Zhujiang River Estuary

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Acta Oceanologica Sinica 2003年第4期22卷 557-568页

作者： Chen Jianfang 1.2, Jin Haiyan 1.2, Yin Kedong3, li Yan 1.2 1. Key laboratory of Submarine Geosciences of State Oceanic Administration, Hangzhou 31.01., china. 2. laboratory of Regional Oceanography, Second Institute of Oceanography, State Oceanic Aedministration, Hangzhou,31.01., china 3. department of Biology, hong Kong university of Science and Technology, hong Kong Kay lab Submarine Geosci State Ocean Adm Hangzhou 310012 Peoples R China State Ocean Adm Inst Oceanog 2 Lab Reg Oceanog Hangzhou 310012 Peoples R China hong Kong Univ Sci & Technol Dept Biol Hong Kong Hong Kong Peoples R China

To investigate organic matter source and reactivity in the Zhujiang River (Pearl River) Estuary and its adjacent areas, particulate organic carbon (POC), particulate hydrolysable amino acids (PHAA), and Chl a during two cruises in July 1.99 and July 2000 were measured. The highest POC and PHAA concentration was observed in the waters with maximum Chl a. The spectra distribution, relative content (dry weight in milligram per gram), PHAA-C% POC and other indicators such as the ratios of amino acids vs. amino sugars (AA/AS) and glucosamine vs. galactosamine (Glum/Gal) suggested that particulate amino acids in the water column and sediments in the Zhujiang River Estuary were mainly derived from biogenic processes rather than transported from terrestrial erosion. In inner estuary where high turbidity was often observable, organic matter was mainly contributed by re-suspension of bottom sediments with revealed zooplankton, microbial reworked characteristics, which suggest that these organic matters were relatively 'old'. In the estuarine brackish region, organic matter in water column is mainly contributed by relatively fresh, easily degradable phytoplankton derived organic matter. During physical - biological processes within the eastuary, organic matter derived from phytoplankton was subjected to alteration by zooplankton grazing and bacterial reworking.

关键词： organic matter reactivity amino acids the Zhujiang River Estuary

Application of Fourier Slice Theorem in Wigner Operator Theory and New Complete Representation

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Communications in Theoretical physics 2009年第11期52卷 829-831页

作者： WANG Tong-Tong~1.and FAN hong-Yi~(2,3)1.School of Mathematics and {1., Huangshi Institute of Technology, Huangshi 435003, china2 department of Material Science and Engineering, university of Science and Technology of china, Hefei 230026, china3 department of {1., Shanghai Jiao Tong university, Shanghai 200030, china School of Mathematics and physics Huangshi Institute of Technology Huangshi 435003 China department of Material Science and Engineering University of Science and Technology of China Hefei 230026 China department of {1. Shanghai Jiao Tong University Shanghai 200030 China

By applying the Fourier slice theorem,S;（λ）=∫;P;（t）e;=F（λcosθ,λsinθ）,where P;（t）is aprojection of f（x,p）=（?）F（u,v）e;dudv along lines of constant,to the Wigner operator we are naturally led toa projection operator（pure state）,which results in a new complete *** Weyl orderimg formalism of theWigner operator is used in the derivation.

关键词： Wigner operator Fourier slice theorem new complete representation

Empirical likelihood confidence regions of the parameters in a partially linear single-index model

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Science china Mathematics 2005年第10期48卷 1333-1348页

作者： XUE liugen~1.& ZHU lixing~2 1. College of Applied Sciences,Beijing university of Technology,Beijing 1.0022,{1. 2. department of Mathematics,hong Kong Baptist university,hong Kong,{1. 1. College of Applied Sciences Beijing University of Technology 100022 Beijing China 2. department of Mathematics Hong Kong Baptist University Hong Kong China

In this paper, a partially linear single-index model is investigated, and three empirical log-likelihood ratio statistics for the unknown parameters in the model are suggested. It is proved that the proposed statistics are asymptotically standard chi-square under some suitable conditions, and hence can be used to construct the confidence regions of the parameters. Our methods can also deal with the confidence region construction for the index in the pure single-index model. A simulation study indicates that, in terms of coverage probabilities and average areas of the confidence regions, the proposed methods perform better than the least-squares method.

关键词： partially linear single-index model, empirical likelihood, confidence region, chi-square distribution, coverage probability.

Entanglement Involved in Pair Coherent State Studied via Wigner Function Formalism

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Communications in Theoretical physics 2009年第12期52卷 1071-1075页

作者： HU li-Yun~(1.2)and FAN hong-Yi~21.College of {1. and Communication Electronics, Jiangxi Normal university, Nanchang 330022, china2 department of {1., Shanghai Jiao Tong university, Shanghai 200030, china College of physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China department of {1. Shanghai Jiao Tong University Shanghai 200030 China

We calculate Wigner function,tomogram of the pair coherent state by using its Schmidt decompositionin the coherent state *** turns out that the Wigner function can be seen as the quantum entanglement(QE)between two two-variable Hermite polynomials(TVHP)and the tomogram is further simplified as QE of twosingle-variable Hermite *** Husimi function of pair coherent state is also calculated.

关键词： pair coherent state Wigner function Tomogram Husimi function

N-way blending problem of circular quadrics

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Science china(Information Sciences) 2010年第8期53卷 1546-1554页

作者： FANG MeiE 1.3 , Wang GuoZhao 2.& MA WeiYin 3 1.School of Computer Science, Hangzhou Dianzi {1., Hangzhou 31.081. china 2 department of Mathematics, Zhejiang {1., Hangzhou 31.01., china 3 department of MEEM, City {1. of hong Kong, hong Kong, china 1. School of Computer Science Hangzhou Dianzi University Hangzhou 310081 China3. Department of MEEM City University of Hong Kong Hong Kong China2. Department of Mathematics Zhejiang University Hangzhou 310018 China

A method of blending circular quadrics with parametric patches is proposed in this paper. It needs n rational bi-cubic B′ezier patches and two S-patches to blend n (n > 2) quadrics. Bi-cubic rational B′ezier patches are used to G 1.-continuously blend each pair of adjacent base surfaces. These patches enclose two n-sided holes. And an S-patch is used to fill each hole, which keeps nearly G 1.continuity. Explicit formulas of control points for both B′ezier patches and S-patches are derived from their constraint conditions, which make modeling by blending quadrics very simple and convenient. In addition, the shapes of the blending surfaces can be intuitively adjusted by free parameters.

关键词： circular quadrics blending n-way S-patch

Stochastic bi-resonance induced by external noise for Ca^2+ signaling in hepatocytes

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Science china Chemistry 2005年第4期48卷 286-291页

作者： ZHANG Jiqian1.2,HOU Zhonghuai1.& XIN Houwen1.1.{1. of Chemical physics,university of Science and Technology of china,Hefei 230026,china 2.College of physics and Electronic Information,Anhui Normal university,Wuhu 241.00,china 1. department of Chemical {1. University of Science and Technology of China 230026 Hefei China 2. College of physics and Electronic Information Anhui Normal University 241000 Wuhu China

The influence of external noise on intracellular Ca2+ oscillations dynamics in a single cell of rat hepatocytes is *** coherence of noise-induced intracellular Ca2+ oscillations reached two maxima for multiple external noise intensity,indicating the occurrence of external noise stochastic bi-resonance (SBR).This phenomenon is compared with our previous result that was induced by internal ***,the deterministic bifurcation character of the system was also discussed.

关键词： stochastic bi-resonance, environment fluctuation, calcium oscillations.

Formation of bulk ferromagnetic nanostructured Fe_(40)Ni_(40)P_(1.)B_6 alloys by metastable liquid spinodal decomposition

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Science china(Technological Sciences) 2009年第7期52卷 1919-1922页

作者： lI Qiang1.2 1.School of physics Science and Technology, Xinjiang {1., Urumqi 830046, china 2 department of physics, The Chinese {1. of hongKong, Shatin N.T., hongKong, china School of physics Science and Technology Xinjiang University Urumqi 830046 China department of {1. The Chinese University of HongKong Shatin N.T. HongKong China

Nanostructured Fe40Ni40P1.B6 alloy ingots of 3―5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 260 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>290 K, the overall microstructure of the specimen changed into a granular morphology. The average grain sizes of the small and large grains are 30 nm and 80 nm, respectively. These prepared samples are soft magnets with saturation magnetization Bs 0.744 T.

关键词： nanomaterials magnetic materials solidification bulk nanostructured alloy Fe40Ni40P1.B6 metastable liquid spinodal decomposition