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Surface modification of γ-Al_2._3 by sodium ions

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chinese Science Bulletin 2001年第3期46卷 188-193页

作者： DENG Feng, YUE Yong, DU Youru, YE Chaohui, KONG Yuhua, WANG Guoxing & LI Xiaoding1. Laboratory of Magnetic Resonance and Atomic and Molecular physics, wuhan {2. of physics and mathematics, chinese academy of Sciences, wuhan 430071, china 2. Hubei {2. of Chemistry, wuhan 430074, china Laboratory of Magnetic Resonance and Atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Hubei institute of Chemistry Wuhan China

1H/2.Na double resonance NMR techniques were employed to study the modification of surface hydroxyls on Y-Al2.3 by sodium ions. 1H-2.Na cross polarization (CP) experiment can resolve three kinds of sodium cations that are closely associated with surface hydroxyl groups, while the signal of deposited salt-Na2.O3, which is not connected to surface hydroxyl groups, is completely suppressed. 1H{2.Na} spin echo double resonance experiments reveal the surface modification in more detail. At low Na+ coverage (5%, 10%), the acidic hydroxyl groups are preferentially coordinated with sodium ions, while both the acidic and the basic hydroxyl groups are accessible for sodium ions at highcoordination that causes proton of the OH groups to be easily dissolved, which is evidenced by the fact that with calcination temperature of the catalysts increasing, the acidic hydroxyl groups are preferentially removed and only the basic hydroxyl groups remain when the calcination temperature is raised to 600℃.

关键词： surface modification γ-Al2.3 NMR hydrodesulfu-rization catalyst.

COLLECTIVELY COMPACT COMPOSITION OPERATOR SEQUENCES BETWEEN BERGMAN AND HARDY SPACES

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Acta Mathematica Scientia 2004年第2期24卷 206-212页

作者：王茂发刘培德 SchoolofmathematicsandStatistics WuhanUniversityWuhan430072China

This paper studies the collective compactness of composition operator sequences between the Bergman and Hardy spaces. Some sufficient and necessary conditions involving the generalized Nevanlinna counting functions fo... 详细信息

关键词： Bergman space Hardy space composition operator collectively compact operator sequence

Riemann boundary value problems and reflection of shock for the Chaplygin gas

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Science china mathematics 2012年第4期55卷 671-685页

作者： CHEN ShuXing 1,& QU AiFang 2.1 School of Mathematical Sciences,Fudan University,Shanghai 2.0433,china 2.wuhan {2. of physics and mathematics,chinese academy of Sciences,wuhan 430071,china 1. School of Mathematical Sciences Fudan University Shanghai 200433 China2. Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China

In this paper,we study two-dimensional Riemann boundary value problems of Euler system for the isentropic and irrotational Chaplygin gas with initial data being two constant states given in two sectors respectively,where one sector is a quadrant and the other one has an acute vertex *** prove that the Riemann boundary value problem admits a global self-similar solution,if either the initial states are close,or the smaller sector is also near a *** result can be applied to solving the problem of shock reflection by a ramp.

关键词： Riemann boundary value problem reflection of shock Chaplygin gas wave interaction Eulersystem

PARTIAL BOCHNER INTEGRABILITY (I)

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Acta Mathematica Scientia 1999年第3期19卷 293-299页

作者：陈泽乾 chinese Acad Sci Wuhan Inst Phys & Math Wuhan 430071 Peoples R China

This paper is concerned with partial Bochner integrals with emphasis on a geometrical study of partial Bochner integrability. Convex sets involving the range of L-1-bounded functions are constructed. These constructio... 详细信息

关键词： Banach space norming set partial Bochner integral

Theory and practice concerning classification for expansive soils using standard moisture absorption water content

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Science china(Technological Sciences) 2005年第1期48卷 31-40页

作者： YAO Hailin1, CHENG Ping2. YANG Yang1 & WU Wanping2.1. institute of Rock and Soil Mechanics, chinese {2. of Sciences, wuhan 430071, china 2. china Communications Second Highway Survey Design and Research institute, wuhan 430052. china 1. institute of Rock and Soil Mechanics Chinese Academy of Sciences 430071 Wuhan China 2. china Communications Second Highway Survey Design and Research institute 430052 Wuhan China

A series of tests on physical, mechanical and chemical properties of expansive soils have shown that the standard moisture absorption water content (SMA) of expansive soils has a good linear relationship with montmorillonite content, cation exchange capacity, specific surface, and it also presents a linear relationship tendency to plastic index and free swell ratio. All this indicates that the above SMA is of clear significance in physics. The plastic index can better reflect the interaction extent between composition and dispersing character of grains, cation and clay minerals. Consequently, SMA can reflect the basic essential properties of expansive soils. On the basis of the classification results that have been published in literature and in consideration of the succession to the classification results for the free swell ratio, this paper puts forward three indexes, i.e. the SMA, plastic index and free swell ratio to classify expansive soils. The tests proposed for the classification indexes are easy to operate, simple in testing device and last a short time. Compared with the latest issued “Classification Standard Code for Rocks and Soils of Railway Projects” (TB10077-2.01), the method proposed in this paper is more convenient and reasonable, and can be popularized, when environment conditions ripen, for the application in field of exploration and design of highway in the areas surrounded by expansive soils.

关键词： expansive soil, standard moisture absorption water content (SMA), plasticity index, free expansive ratio, identification and classification of expansive soils.

Quantitative amendment of high-field ^(13)C NMR spectra of coals

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chinese Science Bulletin 1997年第10期42卷 807-809页

作者： YANG Baolian, LI Liyun and YE ChaohuiLaboratory of Magnetic Resonance and Atomic and Molecular physics, wuhan {2. of physics and mathematics, chinese academy of Sciences, wuhan 430071, china Laboratory of Magnetic Resonance and Atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China

HIGH-RESOLUTION solid state 13C NMR spectroscopy has been a useful tool for the study of *** the use of cross polarization（CP）,magic angle spinning（MAS）and protonhigh-power decoupling（HPD）techniques,high-resolution solid state 13C NMR spectra ofcoals can be obtained and the coal aromaticity（fa）can be measured *** aromaticityis defined as the ratio of aromatic carbon atoms to the total carbon atoms in *** pa-

关键词： 13C NMR coal structure quantitative amendment.

A study of two-dimensional magnetic polaron

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Science china(physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, ZHANG Huaihong1, FENG Mang1,2.& WANG Kelin1,3 1. School of Science, Southwest University of Science and Technology, Mianyang 62.010, china 2. wuhan institute of physics and mathematics, {2. academy of Sciences, wuhan 43.070, china 3. Department of Modern physics, University of Science and Technology of china, Hefei 2.002., china School of Science Southwest University of Science Technology Mianyang 621010 China wuhan institute of {2. mathematics Chinese Academy of Sciences Wuhan 430070 China Department of Modern physics University of Science Technology of china Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

ON THE WEIGHTED OCCUPATION TIME AND SUPPORT OF SUPER-BROWNIAN MOTION CONDITIONED ON NON-EXTINCTION

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Acta Mathematica Scientia 1999年第3期19卷 272-278页

作者：李炳章余旌胡 wuhan Univ Dept Math Wuhan 430072 Peoples R China Acad Sinica Wuhan Inst Phys & Math Wuhan 430071 Peoples R China

This paper investigates the property of super-Brownian motion conditioned on non-extinction. The authors obtain a representation of Laplace functional for the weighted occupation time of this class of processes. By th... 详细信息

关键词： super-Brownian motion non-extinction weighted occupation the support of measure

Compression behavior of Zr_(41)Ti_(14)Cu_(12.5)Ni_(10)Be_(2..5) bulk metallic glass up to 2. GPa

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 319-324页

作者： LI Gong 1, 2., ZHAN Zaiji 2., LIU Jing 3 , YUN Jinku 1 , SUN Liling 2., LIU Riping 1 , ZHANG Jun 2.& WANG Wenkui 1, 2.1. Key Laboratory of Metastable Materials Science and Technology, Yanshan University, Qinhuangdao 066004, china 2. Center for Condensed Matter physics, {2. of physics, chinese academy of Sciences, Beijing 100080, china 3. BSRF, {2. of High Energy physics, chinese academy of Sciences, Beijing 100039, china 1. Key Laboratory of Metastable Materials Science and Technology Yanshan University 066004 Qinhuangdao China 2. Center for Condensed Matter physics Institute of Physics Chinese Academy of Sciences 100080 Beijing China 3. BSRF Institute of High Energy Physics Chinese Academy of Sciences 100039 Beijing China

The compression of a Zr41Ti14Cu12.5Ni10Be2..5 bulk metallic glass (BMG) is investigated at room temperature up to 2. GPa using in-situ high pressure energy dispersive X-ray diffraction with a synchrotron radiation source. The pressure-induced structural relaxation is exhibited. It is found that below about 8 GPa, the existence of excess free volume contributes to the rapid structural relaxation, which gives rise to the rapid volumetric change, and the structural relaxation results in the structural stiffness under higher pressure.

关键词： bulk metallic glass, high pressure, structural relaxation, synchrotron radiation.