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61.
62.
CHENDAOQI 《高校应用数学学报(英文版)》1994,9(1):35-43
In this paper, the normative matrices and their double LR transformation with origin shifts are defined, and the essential relationship between the double LR transformation of a normative matrix and the QR transformation of the related symmetric tridiagonal matrix is proved. We obtain a stable double LR algorithm for double LR transformation of normative matrices and give the error analysis of our algorithm. The operation number of the stable double LR algorithm for normative matrices is only four sevenths of the rational QR algorithm for reed symmetric tridiagonal matrices. 相似文献
63.
Mössbauer spectroscopy was used to investigate the influence of dissolved hydrogen on the interatomic bonds in austenitic steels. It was carried out to prove the decohesion mechanism of hydrogen embrittlement (HE). It is shown that hydrogen increases Debye temperature, i.e., the interatomic bonds in hydrogenated austenitic steel becomes stronger. 相似文献
64.
Dielectric relaxation study of the binary mixtures of poly(vinyl pyrrolidone) (PVP) (Mw=24000, 40000 and 360000 g mol−1) with ethyl alcohol (EA) and poly(ethylene glycol)s (PEGs) (Mw=200 and 400 g mol−1) in dilute solutions of dioxane were carried out at 10.1 GHz and 35°C. The relaxation time of PVP-EA mixtures was interpreted
by the consideration of a wait-and-switch model in the local structure of self-associated ethyl alcohol molecules and also
the PVP chain length as a geometric constraint for the reorientational motion of ethyl alcohol molecules. The formation of
complexes and effect of PVP chain length on the molecular dynamics, chain flexibility and stretching of PEG molecules in PVP-PEG
mixtures were explored from the comparative values of dielectric relaxation time. Further, relaxation time values in dioxane
and benzene solvent confirm the viscosity independent molecular dynamics in PVP-EA mixtures but the values vary significantly
with the non-polar solvent environment. 相似文献
65.
本利用矩阵给出了几类数列的通项公式的求法,把数列通项公式的求法转化为矩阵幂的计算,思路简单、计算简便,并能判别其敛散性。 相似文献
66.
TheImprovementofFischer'sInequalityandHadamard'sInequalityHuangLiping(黄礼平)(DepartmentofBasicSciences,XiangtanMiningInstitute,... 相似文献
67.
The object of the paper is to study the absolute matrix summability problem of Fourier series, conjugate series and some associated
series under a new set of conditions on matrix methods, generalising many known results in the literature. 相似文献
68.
用600keV的Kr~ 离子轰击Al/Cr双层薄膜样品进行界面原子反应及相互混合的研究。实验样品是在单晶硅上蒸镀约500nm厚的铝膜,相继再蒸上所需厚度的铬膜而制成的。轰击剂量为2.0×10~(15)-2.5×10~(16)Kr~ /cm~2。用2.0MeVa粒子对轰击前后的样品进行了卢瑟福背散射(RBS)分析,发现界面处有明显的原子混合存在;当轰击剂量≥1.0×10~(16)Kr~ /cm~2时,RBS谱出现有明显的坪台,经拟合计算和x射线衍射(XRD)测量证实确有化合物Al_(13)Cr_2存在;还分别得到了原子混合量及混合效率与轰击剂量的关系;最后对界面处的原子混合机制进行了讨论。 相似文献
69.
Transition between layered and filamentary types of anisotropy in layered superconducting structures
D. A. Kuptsov 《Annalen der Physik》1992,504(4):296-301
A model of layered superconducting structure consisting of alternating anisotropic superconducting layers S1 and S2 with different transition temperatures is considered. It is shown that due to competition between two origins of anisotropy - effective-mass anisotropy of individual layers and proximity-induced anisotropy the effective anisotropy of the whole system signficiantly varies temperature. The components of the effective-mass tensor mc (along the anisotropy axis) and ma (perpendicular to the anisotropy axis) strongly depend upon temperature. This may lead to transition between layered (mc > ma) and quasi one-dimensional (mc < ma) types of anisotropy as well as to biaxial-type anisotropy which is also temperature dependent. The field distribution in a tilted vortex in a biaxial superconductor is calculated. The change in the properties of the vortex lattice with temperature in such systems is also investigated. The properties of YBa2Cu3Ox/PrBa2Cu3Oy multilayers are discussed in this connection. 相似文献
70.
The morphology of blends of styrenic polymers in a matrix of 75% Nylon-6 prepared in a Brabender Plasti-Corder was examined by scanning electron microscopy. Styrene/acrylonitrile copolymers (SAN) form smaller particles as the AN level increases owing to the corresponding decrease in the SAN–polyamide interfacial tension. Various styrenic polymers containing functional groups, maleic anhydride or oxazoline type, that can react with Nylon-6 during melt processing were added to the SAN phase which also led to a decrease in the particle size owing to the graft copolymer formed in situ. The effects of functional group type, amount of functional groups per chain, amount of functional polymer added, and the miscibility of the styrene/maleic anhydride (SMA) and SAN copolymers on the morphology of the styrenic phase in the Nylon-6 matrix are described. © 1992 John Wiley & Sons, Inc. 相似文献