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The advancement of oscillation theory of functional differential equations

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Chinese Science Bulletin 1998年第12期43卷 974-982页

作者： ZHANG Binggen department of Applied mathematics, ocean university of qingdao, qingdao 266003, china department of Applied mathematics Ocean University of Qingdao Qingdao China

The oscillation theory of functional differential equations (FDEs) is surveyed including (ⅰ) formulation of oscillation problems; (ⅱ) a brief history of the oscillation theory of FDEs; (ⅲ) main topics in the oscill... 详细信息

关键词： functional differential equations oscillation theory.

A NOTE ON THE BACKWARD ERRORS FOR INVERSE EIGENVALUE PROBLEMS

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Journal of Computational mathematics 2003年第2期21卷 201-206页

作者： Xinguo Liu Zhengjian Bai (department of mathematics, ocean university of china, qingdao 2.6071) Departmenl of mathematics Ocean University of China Qingdao 266071

In this note, we consider the backward errors for more general inverse eigenvalue problems by extending Sun's approach. The optimal backward errors are defined for diagonal-ization matrix inverse eigenvalue problem with respect to an approximate solution, and the upper and lower bounds are derived for the optimal backward errors. The results may be useful for testing the stability of practical algorithms.

关键词： Inverse eigenvalue problem Optimal backward error Upper bound Lower bound

The extension of the first main theorem for π-blocks

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Science china mathematics 2006年第5期49卷 620-625页

作者： HAI Jinke department of mathematics, qingdao university, qingdao 2.6071, china College of mathematics ,Shandong university, Jinan 250100, china department of mathematics Qingdao University Qingdao 266071 China College of mathematics Shandong University Jian 250100 China

Let π be a set of primes and G a π-separable group. Isaacs defines the Bπ characters, which can be viewed as the "π-modular" characters in G, such that the Bp′ characters form a set of canonical lifts for the p-modular characters. By using Isaacs' work, Slattery has developed some Brauer's ideals of p-blocks to the π-blocks of a finite π-separable group, generalizing Brauer's three main theorems to the π-blocks. In this paper, depending on Isaacs' and Slattery's work, we will extend the first main theorem for π-blocks.

关键词： π-block, π-separable group, π-regular classes, defect group.

On Browkin's conjecture about the elements of order five in K_2(Q)

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Science china mathematics 2007年第1期50卷 116-120页

作者： Ke-jian XU department of mathematics, qingdao university, qingdao 2.6071, china 1. department of mathematics Qingdao University Qingdao 266071 China

Based on the work of Lenstra, a succinct proof of Browkin’s conjecture about the elements of order five in K2(Q) is given.

关键词： K2 group cyclotomic polynomial lattice binary quartic form.

Lattice dynamical simulation of methane hydrate

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Journal of Natural Gas Chemistry 2010年第1期19卷 43-46页

作者： Lin Wang, Shunle Dong Physics department, College of Information Science and Engineering, ocean university of china, qingdao 266100, Shandong, china [a] Physics department College of Information Science and Engineering Ocean University of China Qingdao 266100 Shandong China

INS （Inelastic Neutron Scattering） spectrum of methane hydrate was measured on MARI （a direct-geometry chopper spectrometer） at Ruther-ford Appleton Laboratory, UK. Compared with ice Ih, it is found that the whole spectrum of methane hydrate moves toward high-energy by about 1.5 meV. Using lattice dynamical （LD） technique, computer simulations of methane hydrate were carried out. In the simulations, four potential models （BE TIP3P, TIP4P, MCY） were employed to calculate the phonon density of states （PDOS）. Comparing the calculated PDOS spectrum with the experimental spectrum, it is found that BF, TIP4P, and TIP3P potential lattices give out well-separated translational and librational bands while MCY potential lattice is unstable to do so and this model is not suitable to describe hydrate system.

关键词： methane hydrate inelastic neutron scattering lattice dynamical simulation

THE PHYSICAL ENTROPY OF SINGLE CONSERVATION LAWS

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Journal of Computational mathematics 1998年第5期16卷 437-444页

作者： (department of mathematics, Peking university, Beijing 100871, china) Beijing Univ Dept Math Beijing 100871 Peoples R China

By means of the comparisons with the formulas in statistical mechanics and thermodynamics, in this paper it is demonstrated that for the single conservation law partial derivative(t)u + partial derivative(x)f(u) = 0, if the flux function f(u) is convex (or concave), then, the physical entropy is S = -f(u); Furthermore, if we assume this result can be generalized to any f(u) with two order continuous derivative, from the thermodynamical principle that the local entropy production must be non-negative, one entropy inequality is derived, by which the O.A. Olejnik's famous E- condition can be explained successfully in physics.

关键词： conservation laws entropy entropy production

Bubble size distribution in surface wave breaking entraining process

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Science china Earth Sciences 2007年第11期50卷 1754-1760页

作者： HAN Lei1,2 & YUAN YeLi2 1 department of ocean Environment, ocean university of china, qingdao 266003, china 2 The First Institute of oceanography, State ocean Administration, qingdao 266061, china 1. department of ocean Environment Ocean University of China Qingdao 266003 China 2. The First Institute of oceanography State Ocean Administration Qingdao 266061 China

From the similarity theorem, an expression of bubble population is derived as a function of the air en-trainment rate, the turbulent kinetic energy (TKE) spectrum density and the surface tension. The bubble size spectrum that we obtain has a dependence of a?2.5+nd on the bubble radius, in which nd is positive and dependent on the form of TKE spectrum within the viscous dissipation range. To relate the bubble population with wave parameters, an expression about the air entrainment rate is deduced by intro-ducing two statistical relations to wave breaking. The bubble population vertical distribution is also derived, based on two assumptions from two typical observation results.

关键词： wave breaking,bubble cloud,bubble size spectrum

Ribosomal Protein Genes S23 and L35 from Amphioxus Branchiostoma belcheri tsingtauense:Identification and Copy Number

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Acta Biochimica et Biophysica Sinica 2005年第8期37卷 573-579页

作者： Xian LI Shi-Cui ZHANG~* Zhen-Hui LIU Hong-Yan LI department of Marine Biology,ocean university of china,qingdao 266003,china department of Marine Biology Ocean University of China Qingdao 266003 China

The complete cDNA and deduced amino acid sequences of the ribosomal proteins S23(AmphiS23)and L35(AmphiL35)from amphioxus Branchiostoma belcheri tsingtauense were identified inthis ***23 cDNA is 546 bp long and encodes a protein of 143 amino *** has a predictedmolecular mass of 15,851 Da and a pI of ***35 cDNA comprises 473 bp,and codes for a proteinof 123 amino acids with a predicted molecular mass of 14,543 Da and a pI of ***23 shares morethan 83% identity with its homologues in the vertebrates and more than 84% identity with those in ***35 is more than 63% identical to its counterparts in the vertebrates and more than52% identical to those in the *** blot analysis demonstrated the existence of 1-2 copiesof the S23 gene and 2-3 copies of the L35 gene in the genome of amphioxus *** *** in sharp contrast to the presence of 6-13 copies of the S23 gene and 15-17 copies of the L35 gene in therat *** is clear that the housekeeping genes like S23 and L35 underwent a large-scale duplication inthe vertebrate lineage,reinforcing the gene/genome duplication hypothesis.

关键词： amphioxus ribosomal protein S23 L35 copy number

A model study on carbon cycle and phytoplankton dynamical processes in the Bohai Sea

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Acta oceanologica Sinica 2003年第1期22卷 47-56页

作者： WeiHao ZhaoLiang FengShizuo InstituteofPhysicaloceanography OceanUniversityofChina(OceanUniversityofQingdao)Qingdao266003China PhysicaloceanographyKeyLabofStateEducationMinistry OceanUniversityofChina(OceanUnivrsityofQingdao)Qingdao266003China

The carbon cycle of lower trophic level in the Bohai Sea is studied with a three-dimensional biological and physical coupled model. The influences of the processes (including horizontal advection, river nutrient load, active transport etc. ) on the phytoplankton biomass and its evolution are estimated. The Bohai Sea is a weak sink of the CO2 in the atmosphere. During the cycle, 13.7% of the gross production of the phytoplankton enter the higher trophic level and 76.8 % of it are consumed by the respiration itself. The nutrient reproduction comes mainly from the internal biogeochemical loop and the rem-ineralization is an important mechanism of the nutrient transfer from organic form to inorganic. Horizontal advection decreases the total biomass and the eutrophication in some sea areas. Change in the nutrient load of a river can only adjust the local system near its estuary. Controlling the input of the nutrient, which limits the alga growth, can be very useful in lessening the phytoplankton biomass.

关键词： Carbon cycle phytoplankton dynamics the Bohai Sea