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921.
采用固相反应法,制备了不同成分的稀释磁性半导体Sn1-xMnxO 2(x=002,004,006).利用x射线衍射和傅里叶变换红外光谱法证明 了锰均匀地掺杂到二氧化锡中.在室温下研究了掺锰二氧化锡基稀释半导体的磁性,发现它具有明显的铁磁性 ,同时对磁性的强弱与锰的含量和烧结温度的关系作了研究.
关键词:
稀释磁性半导体
掺杂
烧结
铁磁性
1-xMnx O2')" href="#">Sn1-xMnx O2 相似文献
922.
In this article ,we chiefly discuss optical part and photoelectrical part, and analyze the result data to make out the relationship between pinhole and special resolution and the influence of PMT on the result data. 相似文献
923.
α-Bloch空间到H∞的加权复合算子 总被引:1,自引:0,他引:1
The article not only presents the boundedness and compactness of the weighted composition operator fromα-Bloch spaces(or littleα-Bloch spaces) to H~∞,but also gives some estimates for the norm of the weighted composition operator. 相似文献
924.
An Iterative Procedure for Evaluating Digraph Competitions 总被引:1,自引:0,他引:1
A competition which is based on the results of (partial) pairwise comparisons can be modelled by means of a directed graph. Given initial weights on the nodes in such digraph competitions, we view the measurement of the importance (i.e., the cardinal ranking) of the nodes as an allocation problem where we redistribute the initial weights on the basis of insights from cooperative game theory. After describing the resulting procedure of redistributing the initial weights, an iterative process is described that repeats this procedure: at each step the allocation obtained in the previous step determines the new input weights. Existence and uniqueness of the limit is established for arbitrary digraphs. Applications to the evaluation of, e.g., sport competitions and paired comparison experiments are discussed. 相似文献
925.
Xiaofeng Ren 《Archive for Rational Mechanics and Analysis》1997,138(2):169-203
Multiple-layer solutions of the balanced bistable equation in infinite tubes are constructed via a variational method. I
start with a characterization of Palais-Smale sequences which easily gives some global minima in the desired function classes
as single layers. Assuming these minima are isolated as critical points, I paste them together to serve as an approximate
multiple-layer solution. If there were no exact solutions near the approximate one, the negative gradient flow of the energy
functional would significantly lower the energy. On the other hand, if the minima are kept far from each other, the energy
of a function near the approximate solution is not much less than that of the approximate solution. This contradiction proves
the existence of a solution.
(Accepted January 11, 1996) 相似文献
926.
René Lamour 《Numerische Mathematik》1991,59(1):815-829
Summary Consider a TPBVP for transferable nonlinear DAE's. In general the shooting equation has a singular Jacobian. A multiple shooting method which has a nonsingular Jacobian and also produces consistent initial values for the integration is presented. The estimation of the condition of the Jacobian shows the well-posedness of the method. Some illustrative examples are given 相似文献
927.
Synthetic saponites have been intercalated with hydroxyl aluminium oligomers and characterized with several techniques. The basal 001 peak of the pillared saponite (PS) is 1. 8 nm. The amount of the aluminium in the tctrahedral sheet is correlative with cross-linking density. The sheet-to-pillar linkage mode may be Si-O-AlpⅥ. The acid sites in pillared saponite may locate either at surface of clay or at that of pillar. The cumene conversion is relative to accessible acid sites on the surface of PS. The pillar density in the PS has an effect on the pore structure which is correlative with shape selectivity during the reaction between ethanol and ammonia. 相似文献
928.
以蒙特卡罗模拟方法对自对耦分布二维随机链q态Potts模型的短时临界行为进行了数值研究.利用初始非平衡演化阶段存在的普适幂指数和有限体积标度行为,数值模拟了在不同形式随机分布时q=3和q=8态Potts模型磁临界指数η和动力学临界指数z.计算结果发现η不依赖于自对偶无序分布的具体形式, 从而以数值方法给出了一个关于淬火掺杂自旋系统的临界普适行为的验证.
关键词:
随机链Potts模型
动力学蒙特卡罗模拟
临界普适性 相似文献
929.
930.