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Percolation transport and magnetic transitions in a phase-separated manganite La_(0.55)Ca_(0.45)MnO_3

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Science China(Technological Sciences) 2011年第9期54卷 2315-2320页

作者： li guang WANG liHua School of Physics and Materials Science Anhui Key Laboratory of Information Materials and Devices Anhui University Hefei 230039 China

The structural, electronic and magnetic properties of La0.55Ca0.45MnO3 were measured. A rapid change of lattice parameters appeared around 190 K associated with the az2 orbital ordering and charge ordering （CO） states that were reflected by both magnetization and resistivity. Great difference of magnetizations between the field-cooling （FC） and zero-field-cooling （ZFC） modes below the charge ordering temperature Too in high magnetic field （H〉4 T） was clearly seen. A field of 5 T （threshold field） is sufficient to completely destroy the antiferromagnetic （AFM） CO state for FC mode in magnetization while it is not the case for ZFC mode. A much larger field （larger than 10 T from ZFC resistivity data） is needed to destroy the CO state for ZFC mode. This could be explained by the coexistence and transformation of two phases reported by Huang et al. For ZFC mode, with increasing H, Tco gradually moves to low temperature regime and the relationship between the critical field Hc （0） to destroy CO state and Tco conforms to a power law Hc = Hc（0）（1 - T/Tco（0））^γ, where Hc （0） is the critical field to destroy the CO state at 0 K, and Too （0） is the CO temperature in zero field.

关键词： manganites phase transition magnetic structure

Detecting the errors in solar system ephemeris by pulsar timing

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Research in Astronomy and Astrophysics 2016年第4期16卷 47-54页

作者： liang li li Guo guang-li Wang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China University of Chinese Academy of Sciences Beijing 100049China

Pulsar timing uses planetary ephemerides to convert the measured pulse arrival time at an obser- vatory to the arrival time at the Solar System barycenter （SSB）. Since these planetary ephemerides cannot be perfect, a method of detecting the associated errors based on a pulsar timing array is developed. By using observations made by an array of 18 millisecond pulsars from the Parkes Pulsar Timing Array, we estimated the vector uncertainty from the Earth to the SSB of JPL DE421, which reflects the offset of the ephemeris origin with respect to the ideal SSB, in different piecewise intervals of pulsar timing data, and found consistent results. To investigate the stability and reliability of our method, we divided all the pulsars into two groups. Both groups yield largely consistent results, and the uncertainty of the Earth-SSB vector is several hundred meters, which is consistent with the accuracy of JPL DE421. As an improvement in the observational accuracy, pulsar timing will be helpful to improve the solar system ephemeris in the future.

关键词： astrometry -- ephemerides -- pulsars: general

NUMERICAL SIMULATIONS OF A CENTERED CONDUCTING BODY ON NATURAL CONVECTION AND HEAT TRANSFER IN AN ENCLOSURE

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Journal of Hydrodynamics 2005年第5期17卷 539-545页

作者： li guang-zheng HUANG Jian-chun College of Civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan430074 China

Numerical simulations are performed for laminar natural convection heat transfer from a centered conducting body enclosed in a square cavity. A high accuracy un steady numerical method is used, combining the unique condition of the pressure, the convergent solutions and the streamfunction value of the inside heat conducting body are given simultaneously. Two examples are simulated with this numerical method and compared with the experimental results. The results of the numerical solutions are consistent with the experimental results. It shows that the numerical method is valid and feasible.

关键词： natural convection in an enclosure inside heat conducting body stream value of solid walls unsteady numerical method

Time Evolution of the Turnover Frequency for Diagnosis of the Coronal Magnetic Field

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Chinese Journal of Astronomy and Astrophysics 2006年第1期6卷 113-119页

作者： guang-li Huang Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008

Two impulsive microwave bursts observed by Owens-Valley Solar Arrays （OVSA） are studied. The fast time variation of the turnover frequency in these bursts is quite different from the constant value in the earlier conclusion. The observational turnover frequencies are consistent with the calculations using the non-thermal gyrosynchrotron radiation model. We find the turnover frequency may play an important role for calculating the coronal magnetic field on the basis of Dulk and Marsh＇s approximations.

关键词： Sun: radio radiation -- Sun: corona- Sun: magnetic fields

Control of Ultra Low Titanium in Ultra Low Carbon Al-Si Killed Steel

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Journal of Iron and Steel Research International 2013年第4期20卷 20-25页

作者： ZHANG Feng li guang-qiang Silicon Steel Department Baoshan Iron and Steel Co.Ltd. Key Laboratory forFerrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and Technology

Titanium is the impurity in some special steel *** existence of titanium decreases the grain size,depresses the yield strength,and results in the low quality of these steels in various ***,titanium should be removed to the *** on the industrial production of ultra low carbon Al-Si killed steel,the physical-chemical behavior of titanium was investigated in vacuum degassing refining（RH）process with and without *** influences of titanium content in hot metal,ladle slag composition,and ladle slag quantity,etc,on titanium content of refined liquid steel were *** results showed that the partition ratio of titanium between ladle slag and liquid steel is in inverse proportion to the 4/3square of aluminum *** maximum partition ratio of titanium between top slag and liquid steel can be obtained by adjusting an optimum slag composition including contents of FeOxand Al2O3and the slag basicity,and the suitable range of them should be controlled higher than 6%,less than 20%,and within 1.5to 3.0,***,desulfurization refining by RH decreases the partition ratio of titanium between ladle slag and liquid steel *** ensure the titanium content stably less than 15×10-6 in a 300tladle,the titanium content in hot metal must be less than 500×10-6 and the thickness of basic oxygen furnace（BOF）slag carrying over must be less than 50mm.

关键词： titanium desulfurization RH refining ultra low carbon steel Al-Si killed steel

Property T for Actions

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Acta Mathematica Sinica,English Series 2019年第11期35卷 1807-1816页

作者： Qing MENG li guang WANG School of Mathematical Sciences Qufu Normal University

We study property T for an action α of a discrete group Γ on a unital C~*-algebra A. Our main results improve some well-known results about property T for groups. Moreover, we introduce Hilbert A-module property T and show that the action α has property T if and only if the reduced crossed product ■has Hilbert A-module property T.

关键词： Property T α-positive definite α-negative definite

The Hyers-Ulam Stability of a Functional Equation Deriving from Quadratic and Cubic Functions in Quasi-β-normed Spaces

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Acta Mathematica Sinica,English Series 2010年第12期26卷 2335-2348页

作者： li guang WANG Bo liU School of Mathematical Sciences Qufu Normal University Qufu 273165 P. R. China

In this paper, we investigate the Hyers-Ulam stability of the following function equation 2f（2x ＋ y）＋ 2f（2x - y） = 4f（x ＋ y）＋ 4f（x - y）＋ 4f（2x）＋ f（2y） - Sf（x） - 8f（y） in quasi-β-normed spaces.

关键词： Hyers-Ulam stability quadratic mapping cubic mapping quasi-β-normed spaces (β,p)-Banach spaces

Two-electron oxygen reduction reaction by high-loading molybdenum single-atom catalysts

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Rare Metals 2020年第5期39卷 455-457页

作者： Xuan Zhao Yan-guang li Institute of Functional Nano and Soft Materials Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China

Hydrogen peroxide(H2O2)is an important environmentally friendly chemical and potential energy carrier and has been widely used for a range of applications,such as paper and pulp bleaching,chemical synthesis and wastewater treatment[1,2].Nowadays,about 95%H2O2is produced from the anthraquinone oxidation process,which unfortunately is energy intensive and far from economical[3].The direct synthesis of H2O2from H2and O2is a green method,but it has the potential hazard of explosion[4].

关键词： synthesis method Hydrogen

Initial Processes of Sulfur Adsorption on Si（100） Surface

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Communications in Theoretical Physics 2005年第4X期44卷 724-726页

作者： MA li WANG Jian-guang WANG guang-Hou National Laboratory of Solid State Microstructures and Department of Physics Nanjing University Nanjing 210093 China

The adsorption of one monolayer S atoms on ideal Si（100） surface is studied by using the self-consistent tight binding linear muffon-tin orbital method. Energies of adsorption systems ors atoms on different sites are calculated. It is found that the adsorbed S atoms are more favorable on B1 site （bridge site） with a distance 0.131 nm above the Si surface. The .S, Si mixed layer might exist at S/Si（100） interface. The layer projected density of states are calculated and compared with that of the clean surface. The charge transfers are also investigated.

关键词： sulfur silicon chemisorption supercell interaction