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961.
A. A. Kabanov 《Russian Journal of Applied Chemistry》2006,79(1):156-158
The thermal stabilities of limestone with varied content of iron are compared. The nature of the differences observed is discussed. 相似文献
962.
Forecasting electricity prices in presentday competitive electricity markets is a must for both producers and consumers because both need price estimates to develop their respective market bidding strategies. This paper proposes a transfer function model to predict electricity prices based on both past electricity prices and demands, and discuss the rationale to build it. The importance of electricity demand information is assessed. Appropriate metrics to appraise prediction quality are identified and used. Realistic and extensive simulations based on data from the PJM Interconnection for year 2003 are conducted. The proposed model is compared with naïve and other techniques. 相似文献
963.
964.
A. B. Vasil’eva A. A. Plotnikov 《Computational Mathematics and Mathematical Physics》2006,46(5):762-767
A singularly perturbed parabolic equation with a nonlinear right-hand side of a special form is examined. A numerical analytical study of such equations is performed. 相似文献
965.
The running coupling and the Kugo-Ojima parameter of unquenched lattice Landau gauge are simulated and compared with the continuum
theory. Although the running coupling measured by the ghost and gluon dressing function is infrared suppressed, the running
coupling has a maximum of α0 ∼ 2 − 2.5 at around q = 0.5 GeV irrespective of the fermion actions (Wilson fermions and Kogut-Susskind (KS) fermions). The Kugo-Ojima parameter
c which saturated to about 0.8 in quenched simulations becomes consistent with 1 in the MILC configurations produced with the
use of the Asqtad action, after averaging the dependence on polarization directions caused by the asymmetry of the lattice.
The presence of the correction factor 1 + c
1/q
2 in the running coupling depends on the lattice size and the sea quark mass. In the large lattice size and small sea quark
mass, c
1 is confirmed of the order of a few GeV. The MILC configuration of a = 0.09 fm suggests also the presence of dimension-4 condensates with a sign opposite to the dimension-2 condensates. The
gluon propagator, the ghost propagator, and the running coupling are compared with recent pQCD results including an anomalous
dimension of fields up to the four-loop level. 相似文献
966.
G.J. Babonas A. Reza I. Simkiene M. Baran U.O. Karlsson 《Applied Surface Science》2006,252(15):5391-5394
Optical properties of Fe-doped silica films on Si were investigated by ellipsometric technique in the region 1-5 eV. Samples were produced by sol-gel method. Precursors were prepared by mixing tetraethoxysilane (TEOS) solution in ethanol and water with aqueous solution of Fe-chloride or Fe-acetate. The coating solution was deposited on Si substrates by spin on technique. The size of Fe-containing nanometric-sized particles depended on technology and varied from 20 to 100 nm. Optical response of complex hybrid samples SiO2:Fe/Si was interpreted in a multi-layer model. In the inverse problem, the Maxwell equations were solved by transfer matrix technique. Dielectric function of Fe-doped silica layers was calculated in the model of effective media. Analysis of optical data has shown that various Fe-oxides formed. Experimental data for films obtained from precursors with Fe-acetate and annealed in hydrogen were well described by the model calculations taking into account a small contribution 1-5% of metal Fe imbedded in silica. The Fe/Fe-O contribution to optical response increased for samples grown from FeCl3-precursor. Ellipsometric data for Fe-doped silica films on Si were interpreted taking into account the structural AFM studies as well as the results of magnetic measurements. 相似文献
967.
Stefan A. Maier 《Optical and Quantum Electronics》2006,38(1-3):257-267
The controlled squeezing of electromagnetic energy into nanometric volumes via surface plasmon-polariton excitations in plasmonic nanoresonators is analyzed using the concept of an effective electromagnetic mode volume V eff, while taking careful account of the plasmon-polariton dispersion and the electromagnetic energy stored in the metal. Together with the quality factor Q of the cavity resonance, this enables a comparison with dielectric optical cavities, where V eff is limited by diffraction. For a Fabry–Perot type planar metallic cavity, a one-dimensional analytic model as well as a three-dimensional finite-difference time-domain simulation reveal that V eff is not bounded by diffraction, and that Q/V eff increases for decreasing cavity size. In this picture, matter–plasmon interactions can be quantified in terms of Q and V eff, and a resonant cavity model for the enhancement of spontaneous Raman scattering is presented. 相似文献
968.
J.S. Tsay H.W. Chang Y.L. Chiou K.T. Huang W.Y. Chan Y.D. Yao 《Journal of magnetism and magnetic materials》2006
Influences of oxygen exposure on the magnetic properties of Co/Ge(1 1 1) ultrathin films have been investigated by surface magneto-optic Kerr effect technique. As the oxygen exposure increases on Co/Ge(1 1 1) films, their magnetic properties could be modified. As an example for 15 ML Co/Ge(1 1 1) films, the coercivity increases from 730 to 920 Oe and the remanence Kerr intensity is reduced for 500 Langmuir (L) of oxygen exposure. Corresponding compositions analyzed by Auger electron spectroscopy measurement shows that the amount of oxygen on the surface layers increases with increasing the oxygen exposure time. Oxygen distributes on the topmost layers of the film. The adsorbed oxygen influences the electronic density of states of Co and results in the changes of the magnetic properties. Besides, the appearance of O/Co/Ge interface could modify the stress anisotropy, and as a result the coercivity of ultrathin Co/Ge(1 1 1) film is enhanced. 相似文献
969.
970.
Solutions are presented for the impulsively started uniformstream and simple shear flows past a point source of momentum,which can be interpreted to describe the position and the widthof the front which transmits the knowledge of the singularitythrough a slightly viscous fluid. These understandings are thengeneralized to show that the front always moves with velocityslower than that of a (strictly monotonic) convective velocity,and also that its width always grows faster than with simplediffusion. Finally, a remarkably simple, exact expression is given forvorticity due to a simple shear flow past a point vortex. 相似文献