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Properties of Toeplitz Operators on the Dirichlet Space Over the Ball

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1617-1628页

作者： yin yin hu Yu Feng LU Liu LIU Department of Mathematics Dalian Maritime UniversityDalian 116024P.R.China Department of Mathematics Dalian University of TechnologyDalian 116024P.R.China

On the Dirichlet space of the unit ball, we study some algebraic properties of Toeplitz operators. We give a relation between Toeplitz operators on the Dirichlet space and their analogues defined on the Hardy space. Based on this, we characterize when finite sums of products of Toeplitz operators are of finite rank. Also, we give a necessary and sufficient condition for the commutator and semi-commutator of two Toeplitz operators being zero.

关键词： Toeplitz operator pluriharmonic symbols Dirichlet space

Quantum Transport and Surface Scattering in Magnetic Metallic Film

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Communications in Theoretical Physics 2008年第9期50卷 771-776页

作者： hu yin DONG Zheng-Chao Department of Physics Huaiyin Teachers College Huaian 223001 China Key Laboratory for Chemistry of Low-Dimensional Materials of Jiangsu Province Huaian 223001 China

Taking into account the quantum size effect and the spin dependence of the electronic band structure,and including the spin dependence of the scattering from bulk impurities and two different sets of surface roughness,wepresent a theory on the electronic transport in magnetic film,in which the average autocorrelation function (ACF) forsurface roughness is described by a Gaussion *** result shows that the conductivity is a sensitive function ofsurface roughness and exchange *** is also found that in the thin film limit and in the lower-order approximationof the surface scattering,the total conductivity is given by a sum of conductivities of all the subbands and the two spinchannels,for each subband and each spin channel the scattering rates due to the impurities and two surfaces are additive.

关键词： magnetic metallic film surface scattering magnetic exchange splitting

Compact Toeplitz Operators on the Weighted Dirichlet Space

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Acta Mathematica Sinica,English Series 2015年第1期31卷 35-43页

作者： Yu Feng LU yin yin hu Liu LIU School of Mathematical Sciences Dalian University of Technology

In this paper, we completely characterize the compactness of Toeplitz operators with con- tinuous symbol on the weighted Dirichlet space.

关键词： Toeplitz operator Dirichlet space compactness

Numerical investigation of thermocapillary migration of the drop for large Marangoni numbers

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Science China(Technological Sciences) 2007年第5期50卷 694-696页

作者： GAO Peng yin Zhaohua hu WenRui National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

An axisymmetric model is adopted to simulate the problem of unsteady drop thermocapillary motion for large Marangoni numbers. Front tracking methods are used in the investigation. It is found that the non-dimensional drop migration ve- locity will decrease with increasing Marangoni number. This agrees well with the experimental results obtained from the 4th Shen-Zhou space ship. In the meanwhile, this is also the first time for numerical simulations to verify the experimental phe- nomenon under large Marangoni numbers.

关键词： thermocapillary migration of drops, microgravity, front tracking methods

Commuting Dual Toeplitz Operators on the Harmonic Dirichlet Space

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Acta Mathematica Sinica,English Series 2016年第9期32卷 1099-1105页

作者： Jing Yu YANG yin yin hu Yu Feng LU Tao YU School of Mathematical Statistics Chifeng University Chifeng 024000 P. R. China School of Mathematical Sciences Dalian University of Technology Dalian 116024 P. R. China

In this paper, we characterize the symbols for （semi-）commuting dual Toeplitz operators on the orthogonal complement of the harmonic Dirichlet space. We show that for φ ,ψ ∈ W1, ∞, SφSψ = SψSφ on （Dh）⊥ if and only if φ and ψ satisfy one of the following conditions：（1） Both φ and ψ are harmonic functions; （2） There exist complex constants α and β, not both O, such that φ = αφ＋β.

关键词： Dual Toeplitz operator harmonic Dirichlet space commutativity

Cooling γ′ precipitation behavior and strengthening in powder metallurgy su-peralloy FGH4096

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Rare Metals 2008年第4期27卷 410-417页

作者： TIAN Gaofeng JIA Chengchang WEN yin LIU Guoquan hu Benfu School of Materials Science and Engineering University of Science and Technology Beifing Beifing 100083 China

Two cooling schemes （continuous cooling and interrupted cooling tests） were applied to investigate the cooling γ precipitation behavior in powder metallurgy superalloy FGH4096. The effect of cooling rate on cooling γ precipitation and the development of γ precipitates during cooling process were involved in this study. The ultimate tensile strength （ErrS） of the specimens in various cooling circumstances was tested. The experiential equations were obtained between the average sizes of secondary and tertiary γ precipitates, the strength, and cooling rate. The results show that they are inversely correlated with the cooling rate as well as the grain boundary changes from serrated to straight, the shape of secondary γ precipitates changes from irregular cuboidal to spherical, while the formed tertiary γ precipitates are always spherical. The interrupted cooling tests show that the average size of secondary γ precipitates increases as a linear function of interrupt temperature for a fixed cooling rate of 24℃/min. The strength first decreases and then increases against interrupt temperature, which is fundamentally caused by the multistage nucleation of γ precipitates during cooling process.

关键词： nickel-base superalloy powder metallurgy (P/M) γ precipitates cooling rate heat treatment

Populations of Ethanol Conformers in Liquid CCI4 and CS2 by Raman Spectra in OH Stretching Region

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Chinese Journal of Chemical Physics 2015年第3期28卷 245-252,I0001页

作者： Nai-yin hu Ke Lin Xiao-guo Zhou Shi-lin Liu Hefei National Laboratory for Physical Sciences at the Microscale Department of Chemical PhysicsUniversity of Science and Technology of China Hefei 230025 China Synergetic Innovation Center of Quantum Information & Quantum Physics University of Science and Technology of China Hefei 230026 China

Combining Raman spectroscopy with density functional theory, the populations of the trans- and gaucheethanol conformers are investigated in carbon tetrachloride （CC14） and carbon disulfide （CS2）. The spectral contributions of two ethanol conformers are identified in OH stretching region. The energy difference between both conformers is estimated with the aid of the calculated Raman cross sections. It can be seen that the trans- ethanol is more stable in CC14 and CS2 solutions. The spectra are also obtained at different temperatures, and it is found the van＇t Hoff analysis is invalid in these solutions. By taking accounts of the Boltzmann distribution and theoretical Raman cross section, the energy difference is found to be increased with temperature, which shows the weak intermolecular interactions can enhance the population of transethanol.

关键词： Raman spectroscopy Ethanol Conformer Energy difference

Ionic Liquid/Poly(ionic liquid)-based Semi-solid State Electrolytes for Lithium-ion Batteries

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Chinese Journal of Polymer Science 2020年第5期38卷 506-513,I0006页

作者： Deng-Zhou Zhang Yong-Yuan Ren yin hu Liang Li Feng Yan hubei Key Laboratory of Plasma Chemistry and Advanced Materials College of Materials Science and EngineeringWuhan Institute of TechnologyWuhan 430205China Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

Ionic liquids(ILs)have appeared as the most promising electrolytes for lithium-ion batteries,owing to their unique high ionic conductivity,chemical stability and thermal stability ***(ionic liquid)s(PILs)with both IL-like characteristic and polymer structure are emerging as an alternative of traditional *** this review,recent progresses on the applications of IL/PIL-based semi-solid state electrolytes,including gel electrolytes,ionic plastic crystal electrolytes,hybrid electrolytes and single-ion conducting electrolytes for lithium-ion batteries are discussed.

关键词： Ionic liquids Poly(ionic liquid)s Semi-solid state electrolytes Lithium-ion batteries

The Effects of Dwarfing Genes (Rht-B1b, Rht-D1b, and Rht8) with Different Sensitivity to GA_3 on the Coleoptile Length and Plant Height of Wheat

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Agricultural Sciences in China 2009年第9期8卷 1028-1038页

作者： TANG Na JIANG ying HE Bei-ru hu yin-gang College of Agronomy Northwest A＆F University Yangling 712100 P.R. China Yangling Branch of China National Wheat Improvement Centre Yangling 712100 P.R.China Shaanxi Key Laboratory of Molecular Biology for Agriculture Yangling 712100 P.R. China

Understanding the effects of wheat dwarfing genes on the coleoptile length and plant height is crucial for the proper utilization of dwarfing genes in the improvement of wheat yield. Molecular marker analysis combined with pedigree information were used to classify wheat cultivars widely planted in major wheat growing regions in China into different categories based on the dwarfing genes they carried. The effects of the dwarfing genes with different sensitivity to gibberellins （GA3） on the coleoptile length and plant height were analyzed. Screening of 129 cultivars by molecular marker analysis revealed that 58 genotypes of wheat contained the dwarfing gene Rht-B1b, 24 genotypes of wheat contained Rht-D1b gene and 73 genotypes of wheat possessed Rht8 gene. In addition, among these 129 cultivars, 35 genotypes of wheat cultivars contained both Rht-B1b and Rht8 genes and 16 genotypes of wheat cultivars contained both Rht-D1b and Rht8 genes. Wheat cultivars with the dwarfing genes Rht-B1b or Rht-D1b were insensitive to GA3, while the cultivars with the dwarfing gene Rht8 were sensitive to GA3. Most of the wheat genotypes containing combination of Rht8 gene with either Rht-B1b or Rht-D1b gene were insensitive to GA3. The plant height was reduced by 24.6, 30.4, 28.2, and 32.2%, respectively, for the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b ＋ Rht8, and Rht-D1b ＋ Rht8 genes. The plant height was reduced by 14.3% for the wheat cultivar containing GA3-sensitive gene Rht8. The coleoptile length was shortened by 25.4, 31.3, 28.4 and 31.3%, respectively, in the wheat cultivars containing Rht-B1b, Rht-D1b, Rht-B1b ＋Rht8 and Rht-D1b ＋ Rht8 genes, while the coleoptile length was shortened only by 6.2% for the wheat cultivar containing Rht8 gene. We conclude that GA3-insensitive dwarfing genes （Rht-B1b and Rht-D1b） are not suitable for the wheat improvement in dryland because these two genes have effect on reducing both plant height and coleoptile length. In contrast, GA3

关键词： bread wheat dwarfing genes Rht-B1b Rht-D1b Rht8 coleoptile length plant height