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991.
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
992.
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
993.
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
994.
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
995.
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
996.
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
997.
N. Raju T. Špaček J. Ježek I. M. Caminiti F. Leinisch K. Hideg P. Ježek W. E. Trommer 《Applied magnetic resonance》2006,30(3-4):373-383
Electron paramagnetic resonance (EPR) spectroscopy of spin-labeled fatty acids was used to investigate their interaction withEscherichia coli-expressed human mitochondrial uncoupling protein UCP2 refolded from inclusion bodies in nonaethylene glycol monododecyl ether (C12E9) micelles. 5-DOXYL-stearic acid and 4-PROXYL-palmitic acid bound to UCP2 exhibited additional clearly separated h+1I, h?1I “immobile” peaks in the low- and high-field region, respectively, separated by 42 and 44 Gauss, and extensively reduced h+1M, h?1M “mobile” peaks, separated by about 30 G, whereas with 7-DOXYL-stearic acid the I and M peaks were smoothed together into one wide peak. Competition of 4-PROXYL-palmitic acid with added palmitic acid, arachidonic acid, and all-cis-8,11,14-eicosatrienoic acid and of 7-DOXYL-stearic acid with arachidonic acid was indicated by the disappearance of the h+1I, h?1I “immobile” peaks, whereas redistribution in micelles without protein was indicated by the rising of the h+1M, h?1M “mobile” peaks. In conclusion, a competition of palmitic, arachidonic, and eicosatrienoic acid within a putative fatty acid binding site was observed for mitochondrial uncoupling protein UCP2. This finding together with the observation of EPR spectra of highly immobilized probes exclusively in the presence of the recombinant UCP2 suggest the existence of a fatty acid binding site on UCP2 which is a prerequisite of the fatty acid cycling mechanism as previously postulated for UCP1. 相似文献
998.
Intense multi- and single-line laser operation is reported from semiconductively preionised atomic fluorine lasers employing an optimised capacitor transfer excitation circuitry. The performance and spectral characteristics of these lasers are discussed and compared to the characteristics of previously described atomic fluorine lasers. The efficiency of one of these lasers described, at optimum conditions, is reaching a value as high as 0.14%. To the best of our knowledge, this is the highest efficiency reported up date, for an atomic fluorine laser. 相似文献
999.
1000.