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51.
In this note we study constant mean curvature surfaces in asymptotically flat 3-manifolds. We prove that, outside a given compact subset in an asymptotically flat 3-manifold with positive mass, stable spheres of given constant mean curvature are unique. Therefore we are able to conclude that the foliation of stable spheres of constant mean curvature in an asymptotically flat 3-manifold with positive mass outside a given compact subset is unique.

  相似文献   

52.
火工品可靠性试验数据的综合分析方法   总被引:1,自引:0,他引:1  
升降法试验数据和固定刺激量下的成败型试验数据,是两种最常见的火工品可靠性试验数据.我们应用Markov链,研究了升降法试验数据下,感度分布参数的极大似然估计的特性.在此基础上,应用Bootstrap方法和Bayes方法,给出了综合分析两种试验数据的方法.最后,将该方法应用于520底火的可靠性鉴定,得出了有益的结论.  相似文献   
53.
Complex formation between aluminium and quercetin(Q) in methanol was investigated by means of 27^Al solid-state, 13^C and 1^H NMR and MS(ESI), UV and IR spectra. Formation of the 1:2 complex was favored in methanol relative to all other solvent and the predominant species observed of Al(Ⅲ) has a 1:2 stoichiometry. The fine structure of 1:2 aluminum complex of quercetin was that the aluminum central atom chelated with two quereetin molecules and two methoxyl groups between two five membered rings, its coordination is six, the chelated site was 3-hydroxy-4-carbonyl.  相似文献   
54.
Differential algebraic equations with after-effect   总被引:4,自引:0,他引:4  
In this paper, we are concerned with the solution of delay differential algebraic equations. These are differential algebraic equations with after-effect, or constrained delay differential equations. The general semi-explicit form of the problem consists of a set of delay differential equations combined with a set of constraints that may involve retarded arguments. Even simply stated problems of this type can give rise to difficult analytical and numerical problems. The more tractable examples can be shown to be equivalent to systems of delay or neutral delay differential equations. Our purpose is to highlight some of the complexities and obstacles that can arise when solving these problems, and to indicate problems that require further research.  相似文献   
55.
Introduction Itiswell knownthatcyanogroupsincyanometa latessuchas[Ag(CN)2]-unitscanbeusedasbridg ingligandsandapolymericstructurecanbeformed throughsilver silver(argentophilic)interactions.This propertyhasbeenexploredintheconstructionofmany oligomericandp…  相似文献   
56.
We present an alternative expression for the parallel sum of k Hermitian nonnegative definite matrices by using the Moore-Penrose inverse of a block matrix.  相似文献   
57.
Based on the studies on the source regions of a group of coronal mass ejections, we have identified two types of large-scale magnetic structures, and suggested that they are intrinsic components of solar magnetism, their destabilization, expansion, and eruption into the interplanetary space are the basic physical processes which lead to the coronal mass ejections. These two types of large-scale structures are giant magnetic loops connecting the two active belts on the opposite hemispheres of the Sun, and the giant filaments (filament channels) and their related magnetic structures. The latter often appear as two parallel rows of sunspots and plage fields, which align side by side in the full disk daily and synoptic magnetograms. The magnetic neutral lines of these large-scale structures are usually longer than 50 heliographic degrees. We name this type of structure “super A configuration”. Sometimes, they are shown as very long filaments and related large-scale magnetic fields. As these magnetic structures are of very large scale, they extend to a great altitude into the corona, they are not easily recognized in magnetic field observations which are usually aimed at solar flare studies. To identify these large-scale structures becomes a key to understanding and predicting coronal mass ejections.  相似文献   
58.
A graph G is 3‐domination critical if its domination number γ is 3 and the addition of any edge decreases γ by 1. Let G be a 3‐connected 3‐domination critical graph of order n. In this paper, we show that there is a path of length at least n?2 between any two distinct vertices in G and the lower bound is sharp. © 2002 John Wiley & Sons, Inc. J Graph Theory 39: 76–85, 2002  相似文献   
59.
测定了二个顺磁性化合物(Ph_1P)[V_2(mp)_6](Ⅰ)和(Ph_4P)_2[NaV(mp)_3 (MeCN)(MeOH)](Ⅱ)(H_2mp=邻巯基苯酚,o-HO_1C_6H_4SH)的固态和/或溶液中的顺磁波谱。(Ⅰ)的77K固态谱及(Ⅱ)的室温固态谱均经模拟计算,认为它们的钒原子处在S=l/2的Ⅰ=7/2状态,(Ⅱ)的低温(77K)溶液谱(乙腈)与Ⅱ的固态谱相同,均有特征的八条精细结构,认为非配对电子基本上定域在钒原子的周围。  相似文献   
60.
扰动周期KdV方程的小波基分析   总被引:2,自引:2,他引:0  
本文利用样条小波基构造近似惯性流形来研究扰动周期KdV方程的长期动力学行为·  相似文献   
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