The self-similarly expanding Eshelby ellipsoidal inclusion: I. Field solution

The solution of a self-similarly (subsonically) dynamically expanding ellipsoidal inclusion with general spatially uniform transformation strain temporally constant is obtained by the use of the Radon transform and the satisfaction of the zero initial conditions and the radiation condition at infinity. It constitutes the self-similar evolution of the inclusion singularity (jump discontinuity at the inclusion boundary) starting from zero dimension. The field solutions for the displacement gradient and particle velocity are presented. Due to the fact that for a self-similarly expanding subsonic motion the hyperbolic system of the partial differential equations of motion becomes elliptic (as proved in Ni and Markenscoff, 2015), it is shown here explicitly that the solution for the displacement gradient in the interior domain of the expanding ellipsoid is constant, thus extending the Eshelby property to the self-similarly expanding ellipsoids as pointed out by Burridge and Willis (1969). Also, the particle velocity is shown to be zero in the interior domain (lacuna) as the waves emitted by the self-similarly expanding inclusion cancel each other due to the symmetries of geometry and motion.     

水热法合成硒化锡纳米盘及其形成机理探讨

本制备方法以二氧化硒(SeO2)为硒源,以氯化亚锡(SnCl2·2H2O)为锡源,以水合肼(N2H4·H2O)为还原剂在180 ℃ 的条件下利用水热法合成了硒化锡纳米盘.产物分别用扫描电子显微镜(SEM)、X射线衍射仪(XRD)表征手段进行了表征,探索了硒化锡纳米盘的形成机理.通过一系列反应物中不同硒元素与锡元素的摩尔比的条件实验,讨论了其对反应所得产物的影响;另外,通过不同反应温度的条件实验,研究了反应体系温度对所得反应产物的影响,讨论了相关的规律.     

High-spin states in neutron-rich Dy isotopes populated in deep-inelastic reactions

High-spin states in neutron-rich Dy isotopes, populated in deep-inelastic processes produced by the interaction of 234 MeV ³⁷Cl ions with a ¹⁶⁰Gd target, have been studied using the highly sensitive EUROBALL IV gamma-ray detector array. The previously known level schemes for ^{159,160,161,162}Dy have been extended to significantly higher spin ( ? 30?) and the i _13/2 band crossing in ¹⁵⁹Dy has been observed for the first time. The experimental results are discussed within the framework of cranked shell model and projected shell model calculations with particular reference to the observed delayed band crossing in ¹⁶²Dy. Received: 20 October 2000 / Accepted: 16 January 2001     

16-Dimensional Smooth Projective Planes with Large Collineation Groups

Smooth projective planes are projective planes defined on smooth manifolds (i.e. the set of points and the set of lines are smooth manifolds) such that the geometric operations of join and intersection are smooth. A systematic study of such planes and of their collineation groups can be found in previous works of the author. We prove in this paper that a 16-dimensional smooth projective plane which admits a collineation group of dimension d 39 is isomorphic to the octonion projective plane P₂ O. For topological compact projective planes this is true if d 41. Note that there are nonclassical topological planes with a collineation group of dimension 40.     

ConvergenceLF spaces

In this paper we examineLF spaces, inductive limits of Fréchet spaces, in two different settings: the categoryCV S of convergence vector spaces and the categoryLC S of locally convex topological vector spaces. Special attention is given to permanence properties and retractivity properties in each case. Some interaction between properties ofLF spaces inCV S and other properties inLC S are investigated.R. Beattie's research was supported by NSERC grant OGP0005316.     

Growth of SrFe12O19 nanowires under an induced magnetic field

Nanowires of SrFe₁₂O₁₉ with diameters of 100 nm and lengths of 2.5 μm have been successfully synthesized in a hydrothermal cell at 180 °C with an 0.35 T magnetic field applied. The growth behavior of the nanoparticles was compared with that under zero magnetic field. The X-ray diffraction patterns indicate that both of the two processes result in formation of pure SrFe₁₂O₁₉, however transmission electron microscope observations show that the morphology of the particles changed from flake-like in zero magnetic field into nanowires in a magnetic field. Compared to the sample obtained under zero magnetic field, the as-prepared one exhibits a higher saturation magnetization. The possible underlying mechanism responsible for the morphology change and the magnetic properties improvement were discussed.     

Crystallization of zinc lactate in presence of malic acid

The influence of malic acid, which acts as an impurity on the cooling crystallization of zinc lactate is investigated in this paper by monitoring the relative supersaturation and the number of crystals during crystallization. The presence of malic acid increases the solution solubility and makes the metastable zone wider; it also changes the habit of the crystal. The purity of the final products is shown to be influenced by the amount and size of seed crystals, cooling rate, seeding temperature and final temperature, but appears to depend mainly on the particle size and level of supersaturation. Residual supersaturation thresholds are observed that depend on the final temperature. A model is proposed to predict the steady-state supersaturation value from the final temperature at a given impurity concentration. This model is based on Kubota and Gibbs equations.     

Molar absorptivity and a 1cm 1% values for proteins at selected wavelengths of the visible and ultraviolet regions. XXIII

The molar absorptivity and A _1cm ^1% values for 150 proteins are reported. The conditions under which these values were obtained and citations to the sources of the data are also provided.     

A computer program system for kinetic analysis of non-isothermal thermogravimetric data: I. Data acquisition and preparation for kinetic analysis

FORTRAN software is described which enables the generation of rate of weight change data (DTG) from percentage weight change measurements (TG), obtained under non-isothermal conditions. The program also transposes this information into the dimensionless extent and rate of reaction at unit temperature intervals by means of a cubic spline interpolation. A simple search routine identifies all DTG spikes in the thermogravimetric record, and the temperature and extent of reaction at which the rate attains its maximum value. This total information serves as input data for the kinetic analysis software to be discussed in part II of this communication. An example of the application of this program to the pyrolysis of bituminous coal is presented.