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991.
Xiaotie Deng Yonggeng Gu Shunming Zhang 《Journal of Mathematical Analysis and Applications》2006,313(1):353-365
We examine the valuation of American put options by a semi-analytical method, and obtain the prior estimate and the convergence of the approximate solution. Our proofs are based on the embedding theorem in Sobolev space and the theory of functional analysis, in particular, the theory of weak compactness. The results in this paper theoretically confirm empirical observations that these methods are accurate and computationally efficient. 相似文献
992.
Yongsheng Liu Jincang Zhang Shixun Cao Xiaoyong Zhang Xi Li Kang Deng 《Solid State Communications》2006,138(2):104-109
In the compound MnBi, a first-order transition from the paramagnetic to the ferromagnetic state can be triggered by an applied magnetic field and the Curie temperature increases nearly linearly with an increase in magnetic field by ∼2 K/T. Under a field of 10 T, TC increases by 20 and 22 K during heating and cooling, respectively. Under certain conditions a reversible magnetic field or temperature induced transition between the paramagnetic and ferromagnetic states can occur. A magnetic and crystallographic H-T phase diagram for MnBi is given. Magnetic properties of MnBi compound aligned in a Bi matrix have been investigated. In the low temperature phase MnBi, a spin-reorientation takes place during which the magnetic moments rotate from being parallel to the c-axis towards the basal plane at ∼90 K. A measuring Dc magnetic field applied parallel to the c-axis of MnBi suppresses partly the spin-reorientation transition. Interestingly, the fabricated magnetic field increases the temperature of spin-reorientation transition Ts and the change in magnetization for MnBi. For the sample solidified under 0.5 T, the change in magnetization is ∼70% and Ts is ∼91 K. 相似文献
993.
富马酸单乙酯(FAME)的单脉冲1H MAS谱由-高分辨成分与-宽线谱成分组成.高分辨成分可由Hahn回波脉冲序列单独获得.文中通过变温1H MAS与CRAMPS实验对两组分的性质进行了系统的研究.发现当温度趋于样品的熔点时,其1H CRAMPS谱可观察到化学位移明显区别的两套谱,它们分别对应于1H MAS谱的高分辨与宽线组分.实验表明:高分辨成分来自FAME样品的-塑性相,而宽线组分来自通常的刚性相.文中所给出的实验事实充分说明1H MAS与CRAMPS技术是研究有机塑性固体的强有力的工具. 相似文献
994.
995.
996.
997.
The global existence and finite time blow up of the positive solution for a nonlinear degenerate parabolic equation with non-local source are studied. 相似文献
998.
Three diethylgallium complexes of type Et2GaL [L = N‐(4‐methoxy) benzylidenethiobenzahydrazonato ( 1 ), N‐(4‐N,N‐dimethylamino)benzy lidenethiobenzahydrazonato ( 2 ) and N‐(9‐anthryl)methylenethio benzahydrazonato ( 3 )] were synthesized by the reaction of triethylgallium with appropriate N‐arylmethylenethiobenzahydrazones. The compounds obtained were characterized by elemental analysis, 1H NMR, IR and mass spectroscopy, respectively. Monolayer light‐emitting diodes based on the diethyl[N‐arylmethylenethio benzahydrazonato]gallium doped poly(vinylcarbazole) were fabricated using a spin coating method. The photoluminescent and electroluminescent emission spectra of 1 and 3 were measured (429 and 479 nm for 1 and 3 , respectively). The electroluminescent properties of 1 and 3 were also studied. The electroluminscence bands are located in the blue/green region (465 and 510 nm for complexes 1 and 3 , respectively). Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
999.
Deng Lü-bi 《Frontiers of Physics in China》2006,1(1):47-53
The present theory of atom optics is established mainly on the Schr?dinger equations or the matrix mechanics equation. The
authors present a new theoretical formulation of atom optics: Feynman’s path integral theory. Its advantage is that one can
describe the diffraction and interference of atoms passing through slits (or grating), apertures, and standing wave laser
field in Earth’s gravitational field by using a type of wave function and calculation is simple. For this reason, we derive
the wave functions of particles in the following configurations: single slit (and slit with the van der Waals interaction),
double slit, N slit, rectangular aperture, circular aperture, the Mach-Zehnder-type interferometer, the interferometer with the Raman beams,
the Sagnac effect, the Aharonov-Casher effect, the Kapitza-Dirac diffraction effect, and the Aharonov-Bohm effect. The authors
give a wave function of the state of particles on the screen in abovementioned configurations. Our formulas show good agreement
with present experimental measurements. 相似文献
1000.
Zike Deng 《Journal of Mathematical Analysis and Applications》1985,112(2):471-486
In this paper the fuzzy pseudo metric is introduced in the fuzzy unit interval and based on it theorems on m-uniformization and metrization of fuzzy topological spaces are proved. 相似文献