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991.
Yan Yaqiang 《Southeast Asian Bulletin of Mathematics》2002,25(4):769-782
We introduce some practical calculation of the weakly convergent sequence coefficients of Orlicz sequence spaces equipped with Luxemburg norm and Orlicz norm. For the N-function (u) of which the index function is monotonuous, the exact value WCS(l()) of Orlicz sequence space l() with Luxemburg norm is available, i.e. WCS(l()) =
or
WCS(l) of l with Orlicz norm has the exact value
or estimation
相似文献
992.
This paper discusses the spectral properties and numerical simulation for the second order elliptic operators with rapidly
oscillating coefficients in the domains which may contain small cavities distributed periodically with period ε. A multiscale
asymptotic analysis formula for this problem is obtained by constructing properly the boundary layer. Finally, numerical results
are given, which provide a strong support for the analytical estimates 相似文献
993.
We consider finite element operators defined on ``rough' functions in a bounded polyhedron in . Insisting on preserving positivity in the approximations, we discover an intriguing and basic difference between approximating functions which vanish on the boundary of and approximating general functions which do not. We give impossibility results for approximation of general functions to more than first order accuracy at extreme points of . We also give impossibility results about invariance of positive operators on finite element functions. This is in striking contrast to the well-studied case without positivity.
994.
Thermal analysis has been employed to measure changes of the heat capacity of ferromagnetic materials such as alloys in the region of the Curie temperature. Thermal response for these materials is usually small in this region. The necessary increase in sensitivity was achieved by applying temperature modulation. Results obtained by this technique including temperature-modulated differential thermal analysis simultaneously with A.C. thermomagnetometry are presented. 相似文献
995.
The structure and optical properties of the films of ternary compounds AgInSe2, CuInSe2 and Cu
x
Ag1–x
InSe2 solid solutions obtained by pulsed laser evaporation are investigated. It has been established that the films like bulk crystals have the structure of chalcopyrite. By the transmission and reflection spectra near the edge of natural absorption the refractive index and coefficient of optical absorption are calculated and the energies of interband transitions and the crystalline and spinorbit splitting are determined. 相似文献
996.
997.
Highly ordered Prussian blue nanowires with diameter of about 50 nm and length up to 4 m have been fabricated by an electrodepositing technology with two-step anodizing anodic aluminum oxide films. The Mössbauer spectra taken between 15 and 300 K indicate that the hyperfine parameters decrease as the temperature increases. The temperature dependence of the quadrupole splitting, the isomer shift and the spectra area are discussed. A decrease of Debye temperature for Prussian blue nanowires was found with respect to that of Prussian blue bulk. 相似文献
998.
庞小峰 《原子与分子物理学报》2002,19(3):319-326
ATP水解作用所释放的能量能引起蛋白质分子中额外电子的激发,其激发与氨基酸残基晶格畸变相互作用,使额外电子自陷成孤子,这孤子在附着有供体(D)和受体(A)的蛋白质分子中运动时,由于孤子与供体电子的相互作用而"自局域"在孤子上进行迁移,从而可把电子供给受体.使用作者提出的孤子理论研究了这种迁移的特征,计算了在这种非平衡态过程中由孤子迁移电子的速率和动能系数,得到了一些有趣的结果,揭示了这种迁移的本质,求得了迁移的大小. 相似文献
999.
Crystallization kinetics and thermodynamic properties of nucleated isotactic polypropylene (PP) are analyzed using Hoffman—Lauritzen crystallization theory to determine the mechanistic effects of the nucleators. Calorimetric data provides quantitative comparisons between nucleating efficiences of the (Millad) and (NJSTAR) nucleator in Metallocene (M) and Ziegler—Natta (ZN) PP. The two types of PP without nucleators showed similar crystallization behavior though the T°m for ZN-iPP was about 10°C higher than M-iPP. Both nucleators show significant improvement in crystallization rate in both types of PP. In addition, Millad outperforms NJSTAR. The magnitude of the kinetic response is,however, different and both the nucleators appear to function better in ZN than in Metallocene PP. nucleated PP shows predominantly the form. The amount of the form is thermal history dependent and changes with supercooling (T=T°m–Tc). Similar equilibrium melting temperature (T°m) in the nucleated and control PPs indicates the lack of any thermodynamic effect of the nucleator. All nucleated PPs show a much lower secondary nucleation rate constant, Kg.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
1000.
Aram A. Sahakyan Sergei K. Nikoghosyan Hrant N. Yeritsyan 《Central European Journal of Physics》2008,6(4):797-801
The influence of irradiation by electrons with an energy of 8 MeV, at dose intervals between 1013 and 2×1018el/cm2, on the properties of impurity doped, high-temperature superconductor YBa2Cu3−x
M
x
O
y
(M = Fe, Ni; x=0; x=0:01) ceramics has been studied.
It has been established that, as the irradiation dose is increased, the onset temperature of the transition to the superconducting
state (T
c
on
), and the intergranular weak link coupling temperature between granules (T
m
J
), exhibit an oscillation around their initial values of approximately about 1–1.5 K. This oscillation indicates that the
process of radiation defect formation in HTSC occurs in multiple stages. It was also found that the critical current (J
c
)decreases with an increase of the irradiation dose, and exhibits a local minimum at a dose of 8×1016el/cm2coinciding with minima for T
c
on
and T
m
J
at this dose. It was found that the introduction of Fe atoms to the ceramic decreases T
m
J
, while introducing Ni atoms decreases both T
c
on
and T
m
J
; it is suggested that this is a result of Ni substitution of Cu both in Cu2 plane sites and Cu1 chain sites. The introduction
of Ni causes a large change in the intergranular critical current density, J
c
. A critical irradiation dose is obtained (2×1018)after which all HTSC parameters strongly decrease, i. e. the superconductivity of HTSC is destroyed.
相似文献