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91.
We consider perturbed linear systems of difference equations with periodic coefficients. The zero solution of a nonperturbed system is assumed asymptotically stable, i.e., all eigenvalues of the monodromy matrix belong to the unit disk {||<1}. We obtain conditions on the perturbation of this system under which the zero solution of the system is asymptotically stable and also establish continuous dependence of one class of numeric characteristics of asymptotic stability of solutions on the coefficients of the system. 相似文献
92.
Imamoglu Mustafa Aydin Ali Osman Dundar Mustafa S. 《Central European Journal of Chemistry》2005,3(2):252-262
A preconcentration method of gold, palladium and copper based on the sorption of Au (III), Pd (II) and Cu (II) ions on a column
packed with 3-(2-aminoethylamino)propyl bonded silica gel is described. The modified silica gel was synthesized and characterized
by FT-IR and C, H, N elemental analysis. At column preconcentration, the effects of parameters such as pH, volume, flow rate,
matrix constituents of solutions and type of eluent on preconcentration of gold, palladium and copper were studied. The recoveries
of Au (III), Pd (II) and Cu (II) were 98.93±0.51, 98.81±0.36 and 99.21±0.42 % at 95 % confidence level, respectively. The
detection limits (δ) of the elements were 0.032, 0.016 and 0.012 μg ml−1, respectively. The preconcentration method was applied for determination of gold and palladium in certified reference material
SARM 7B and copper in river and synthetic seawater by FAAS. Gold, palladium and copper were determined with relative error
lower than 10 %. 相似文献
93.
E.D. Aydin S. Katsimichas 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,95(3):349-363
In this paper, the finite-element-spherical harmonics (FE-PN) method is applied to the solution of transient Boltzmann transport equation. Firstly, transport and diffusion calculations are obtained for homogeneous and inhomogeneous circular regions. Results are compared in order to show the effects of different absorption coefficient values on the propagation of photons. Significant differences between two theories are shown to occur especially in cases when the absorption is increased. Secondly, to validate the FE-PN method, results from this method are compared with Monte Carlo calculations for different cases. Comparisons show good agreements between FE-transport and Monte Carlo solutions and demonstrate the correctness of the results obtained. 相似文献
94.
This paper abstracts some results of M. Bresar and J. Vukman [1] on the orthogonal derivations of semiprime rings to (σ, τ)-derivations and generalized (σ, τ)-derivations. 相似文献
95.
Cubukcu E Aydin K Ozbay E Foteinopoulou S Foteinopolou S Soukoulis CM 《Physical review letters》2003,91(20):207401
We experimentally and theoretically demonstrate single-beam negative refraction and superlensing in the valence band of a two-dimensional photonic crystal operating in the microwave regime. By measuring the refracted electromagnetic waves from a slab shaped photonic crystal, we find a refractive index of -1.94 that is very close to the theoretical value of -2.06. A scanning transmission measurement technique is used to measure the spatial power distribution of the focused electromagnetic waves that radiate from a point source. The full width at half maximum of the focused beam is measured to be 0.21 lambda, which is in good agreement with the finite difference time domain method simulations. We also report a subwavelength resolution for the image of two incoherent point sources, which are separated by a distance of lambda/3. 相似文献
96.
[reaction: see text] A series of water-soluble green perylenediimide (PDI) dyes have been synthesized. On red light excitation, these dyes were shown to be efficient generators of singlet oxygen, and in cell culture media, they were shown to display significant light-induced cytotoxic effects on the human erythroleukemia cell line (K-562). It appears that highly versatile PDI dyes are likely to find new applications in photodynamic therapy. 相似文献
97.
98.
Bound state poles of the form factors in eikonal approximation and infinite component wave equations
We investigate the form factor in eikonal approximation for the whole region of momentum transfer t in electrodynamics and in φ3 theory, and determine the poles in the time-like region below the threshold. A covariant mass formula is obtained similar to the one derived from four point functions in eikonal approximation. The mass formula does not become imaginary for large values of the coupling constant. The relation to positronium Regge trajectory and infinite component wave equations is discussed. 相似文献
99.
Christopher J. Cramer Armagan Kinal Marta Wloch Piotr Piecuch Laura Gagliardi 《ChemInform》2007,38(1):no-no
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. 相似文献
100.