Bers型空间和复合算子

For α∈（0,∞),let Hα^∞（or Hα^∞,0)denote the collection of all functions f which are analytic on the unit disc D and satisfy |f(z)|(1-|z|^2)^α=O(1)(or|f(z)|(1-|z|^2)^α=o(1) as |z|→1).Hα^∞,0)is called a Bers-type space (or a little Bers-type space).In this paper,we give some basic properties of Hα^∞，Cψ，the composition operator associated with a symbol function ψ which is an analytic self map of D,is difined by Cψf=f o ψ,We characterize the boundedness,and compactness of Cψ which sends one Bers-type space to another function space.     

Dynamic interaction between a sub-interface crack and the interface in a bi-material: time-domain BEM analysis

Summary Transient response of a sub-interface crack in a bi-material is studied with emphasis on the dynamic interaction between the crack and the interface, by combining the traditional time-domain displacement boundary element method (BEM) and the non-hypersingular traction BEM. Computations are performed for an unbounded bi-material with a crack subjected to impact tensile loading on its faces or incident impact waves and a bounded rectangular bi-material plate under remote impact tensile loading. Numerical results of the dynamic stress intensity factors (DSIFs) and dynamic interface tractions are presented for various material combinations and crack locations. It is shown that pronounced increases in DSIFs and the interface tractions may be caused in some cases because of the dynamic interaction between the crack and the interface.This work was initialized during the second author's stay at Institute of Mechanics, TU Darmstadt, Germany under the support of the Alexander von Humboldt Foundation. Discussion on the BEM formulation with Dr. Seelig is gratefully acknowledged. The first two authors are also grateful for the partial support by the China National Natural Science Foundation under Grant No. 10025211 and the NJTU Scientific Paper Fund (PD195).     

印度红花岗石与芝麻白花岗石的光谱的研究

采用了电感耦合等离子体原子发射光谱法、X荧光光谱法测定了印度红花岗石和芝麻白花岗石的组成，测定了它们的X射线谱及红外光谱。印度红花岗中的Fe、Ca和Al、Ti、K、S、P、Mg、Mn的含量分别高于和低于芝麻白花岗石中的Al、Ti、K、S、P、Mg、Mn、Fe、Ca。印度红花岗石的红色是由于它们含有Fe的有色矿物而产生的。     

X-ray photoelectron spectroscopy analysis of the surface composition of Azospirillum brasilense in relation to growth conditions

X-ray photoelectron spectroscopy (XPS) has been used to determine the surface chemical composition of the Gramnegative bacterium Azospirillum brasilense as a function of growth conditions. As opposed to growth in complex medium, growth in synthetic medium led to low reproducibility of XPS results, and did not show a significant variation of the cell surface composition as a function of culture time; moreover, the molecular composition obtained by modelling the XPS data was found to be generally poorer in proteins, and richer in polysaccharides and in hydrocarbon-like compounds. The direct correlation between the phosphate concentration and the concentration of carbon bound only to carbon and hydrogen, ---(C,H), indicated that hydrocarbon-like compounds detected at the surface of cells grown in synthetic medium are essentially phospholipids. The poor reproducibility of the XPS data obtained for cells grown in synthetic medium and the random observation of phospholipids at the outermost cell surface are not due to cell disruption or to migration of intracellular components during sample preparation; exposure of phospholipids at the cell surface reflects either actual variations of the composition of the native surface induced by nutrient limitation or reorganization of cell surface polymers upon freeze drying.     

Equivalence theorem for constrained optimization of the LegendreK-transform of a concave function

The most common way of determining the steady states of a system is through the optimization of a concave function on a convex set. This applies only to cases where the objective function depends exclusively onextensive variables. In fields such as econometrics, physics, or chemistry, controllable quantities (and therefore constrained variables) are generally referred to asintensive parameters, and the states are described through a potential function. In the following pages, we examine how these two aspects can be connected.The author would like to thank Professor A. Lichnerowicz, Collège de France, for encouragement and helpful comments.     

STUDY ON COAL-BED GAS COMPOSITIONS AND ITS GEOCHEMICAL CHARACTERISTICS IN CHINA

This paper considers, through a lot of measured data of coal-bed gas, that the coal-bed gas is a kind of mixed gas of complex composition with some heavy hydrocarbons. In general, it is not a dry gas. The coal-bed hydrocarbon gases can obviously be divided into three stages of gas-storage: "poor hydrocarbon-storing stage", "rich hydrocarbon-storing stage" and "declining hydrocarbon stage". Authors point out that the normal gas geochemical indexes can relatively well show the geochemical chatacteristics of coal-bed gas. But, "the Benzene Index (B)" is a good indicator to identify the gas original types, and "the Hexane Index(H)" can show the gas evolution law and the organic matter maturity.     

Phase composition of manganese-alumina catalysts for the reactions of deep oxidation

X-ray powder diffraction, transmission electron microscopy and differential dissolution were used for investigation of the phase transformation peculiarities of biphasic manganese-alumina catalysts during their thermal treatment. An effect of interaction between aluminium and manganese oxides depending on the sample preparation procedure was found.     

Effect of operation parameters on temperature rising elution fractionation and crystallization analysis fractionation

Crystallization analysis fractionation and temperature rising elution fractionation are two techniques used to estimate the chemical composition distributions of semicrystalline copolymers. This study investigates the cooling rate and cocrystallization effects for both techniques with a series of ethylene/1‐olefin copolymers and their blends. Ideally, both techniques should operate in the vicinity of thermodynamic equilibrium so that crystallization kinetic effects are avoided. The results show that, in fact, crystallization kinetic effects play an important role at the typical cooling rate used with both techniques. Cocrystallization is significant when fast cooling rates are used. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 1762–1778, 2003     

A finite element method for transient compressible flow in pipelines

A finite element method is developed to solve the partial differential equations describing the unsteady flow of gas in pipelines. Excellent agreement is obtained between simulated results and experimental data from a fullscale gas pipeline. The method is used to describe very transient flow (blowout), and to determine the performance of leak detection systems, and proves to be very stable and reliable.     

Periodic solutions of rigid body–viscous flow interaction

This paper describes the work on extending the finite element method to cover interactions between a viscous flow and a moving body. The problem configuration of interest is that of an arbitrarily shaped body undergoing a simple harmonic motion in an otherwise undisturbed incompressible fluid. The finite element modelling is based on a primitive variables representation of the Navier-Stokes equations using curved isoparametric elements. The non-linear boundary conditions on the moving body are obtained using Taylor series expansion to approximate the velocities at the fixed finite element grid points. The method of averaging is used to analyse the resulting periodic motion of the fluid. The stability of the periodic solutions is studied by introducing small perturbations and applying Floquet theory. Numerical results are obtained for several example body shapes and compared with published experimental results. Good agreement is obtained for the basic non-linear phenomenon of steady streaming.