Fe/Si多层膜的层间耦合与界面扩散

对以本征Si及重掺杂ｐ型和ｎ型Si作为中间层的Fe/Si多层膜的层间耦合进行研究，并通过退火，增大Fe，Si之间的扩散，分析界面扩散对层间耦合的影响. 实验结果表明，层状结构良好的制备态的多层膜，Fe，Si之间也存在一定程度的扩散，它是影响层间耦合的 主要因素，远远超过了半导体意义上的重掺杂，使不同种类的Si作为中间层的层间耦合基本 一致.进一步还发现，在一定范围内增大Fe，Si之间的扩散，即使多层膜的层状结构已经有了相当的退化，Fe/Si多层膜的反铁磁耦合强度基本保持不变. 关键词： Fe/Si多层膜 层间耦合 界面扩散     

Stability of a deflagration front in compressible media

A two-dimensional linear analysis of the planar flame front stability for a compressible fluid is presented. The analysis shows that there are two types of perturbations. The first type, corresponding to waves in incompressible media, has already been studied by Landau. It predicts absolute instability of the flame front. The second type of perturbations is due to fluid compressibility and the dependence on upstream flow parameters of the flame front velocity. Three different regimes for these perturbations are possible: stable, acoustically unstable, and absolutely unstable. The instability results in a pronounced pressure wave generation.A one-dimensional analysis of the interaction of the flame front with flow boundaries is performed. Under some circumstances, this interaction is shown to cause exponential growth of the perturbations.     

Superferromagnetic state of α-Fe in Fe implanted Co6Ag94 studied by Mössbauer spectroscopy

After having introduced by ion implantation ⁵⁷Fe to a local concentration of 7 at% into Co₆Ag₉₄, we observed it by conversion electron Mössbauer spectroscopy in the as-prepared state and after isochronal annealing. A superferromagnetic state is inferred, which is correlated with the ordering of the magnetic moments on the Fe clusters through chain-like or dendritic Co/Fe linear structures. The magnetic moment disordering temperature lies above 473 K.     

NAA of IAEA lake sediment RM SL-3 for 45 elements

45 elements have been determined by NAA in an IAEA Lake Sediment RM SL-3 Multitechniques were used to fully tap the potential of NAA in terms of the number of the determinable elements and the accuracy of each data.     

液态铅的电阻率

采用精确的结构因数实验数据和Ｂｅｈａｖｉ模型赝势，用Ｚｉｍａｎ理论计算了液态铅的电阻率．计算结果和实验数据符合很好．讨论了Ｚｉｍａｎ理论对液态铅的适用性以及适合于液态铅的赝势的特征．     

合成金属有机(高分子)铁磁体

本文介绍了纯有机(高分子)磁体及金属有机(高分子)磁体的种类、结构和发展慨况,并概述了近年来我们所合成的常温稳定二茂铁型有机(高分子)铁磁体及其应用前景.     

欧拉示性数在确定不动点方面的一些应用

本文根据空间的欧拉示性数是否为零．来确定该空间的自映射是否有不动点的几个方面的应用。     

分层有限元及其数学特性研究

提出了三维问题的分层有限元迭代算法，对算法的数学特性进行了初步探讨。理论分析表明，该算法适应于一些椭圆型问题，且其工作量小，方便可靠。最后，给出具体的算例。     

IR finite one-loop box scalar integral with massless internal lines

The IR finite one-loop box scalar integral with massless internal lines has been recalculated. The result is very compact, simple and valid for arbitrary values of the relevant kinematic variables. It is given in terms of only two dilogarithms and a few logarithms, all of very simple arguments. Received: 31 January 2002 / Published online: 26 April 2002