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961.
Abdullah Algin 《Czechoslovak Journal of Physics》2002,52(9):1011-1019
A two-parameter deformed N = 2 SUSY algebra is constructed by using the q-deformed bosonic and fermionic Newton oscillator algebras. The Fock space representation of the (q
1,q
2)-deformed N = 2 SUSY algebra is analyzed. The comparison between the algebra constructed and earlier versions of deformed N = 2 SUSY algebras is also made. 相似文献
962.
The intensity of the luminescence generally increases with radiation dose and measurement of these phenomena can be used to characterise the degree of dependence on beta doses. In this study, in order to test whether this is a significant problem on the optically stimulated luminescence (OSL) studies, the radiation dose response of the OSL signal from samples of chlorides contained in feldspars have been investigated by irradiating the samples with beta doses. The infrared-emitting diodes were used with a wavelength of (880±80) nm, and an IRSL (infrared stimulated luminescence) intensity parametres, m, was described and found m = 1±0.03. 相似文献
963.
Analogy is used to treat the system of non-interacting integrate-and-fire neurons as an ideal Fermi gas. It allows to obtain the nonlinear gain curve in the form of sigmoid in agreement with biological findings. As the by-product the gain-threshold mechanism in neurons is presented. Surprisingly enough, this is in agreement with new biological findings, too. Besides, the application of this mechanism to the dynamics of neurons leads to the non-monotone transfer function. 相似文献
964.
965.
Y. AYVAZK. ÖZGAN 《Journal of sound and vibration》2002,255(1):111-127
The purpose of this paper is to apply the modified Vlasov model to the free vibration analysis of beams resting on elastic foundations and to analyze the effects of the subsoil depth, the beam length, their ratio and the value of the vertical deformation parameter within the subsoil on the frequency parameters of beams on elastic foundations. This analysis has been carried out by the aid of a computer program based on the finite element method. The first ten frequency parameters are presented in tabular and graphical forms to evaluate the effects of the parameters considered in this study. Then mode shapes corresponding to the first six of the frequency parameters are given in figures. It is concluded that the effect of the subsoil depth on the frequency parameters of beams on an elastic foundation is generally larger than those of the other parameters considered in this study. 相似文献
966.
A. Biber A. Golick M. Tomak 《International Journal of Infrared and Millimeter Waves》2002,23(9):1315-1325
This paper presents the analytical proof of Time-Domain Mapping Method for the spherical resonator made up of uniaxial crystal. In this way, the main types of caustics inside the spherical resonator made up of uniaxial crystal, which were investigated numerically before, are confirmed analytically. It is engraved that the problem of the ray flow inside the spherical resonator can be reduced to the problem of the ray flow inside metal cavity shaped as spheroid. 相似文献
967.
Squaraines are a group of fluorescent dyes and pigments derived from squaric acid and dialkylanilines well known in applications such as photoreceptors, organic solar cells, optical recording media, and non-linear optics. Their very promising spectral properties, long wavelength absorption and emission, and high absorptivity and quantum yields have not been exploited so far in relation to optical sensor design. They exhibit excellent solubility in sol-gel matrices, and the ligand is an integral part of the fluorophore system, which makes the molecule a fluoroionophore. In this work, potassium-sensing agent, bis[4-N-(1-aza-4,7,10,13,16-pentaox acyclooctadecyl)-3,5-dihydroxyphenyl] squaraine has been used for potassium sensing in a sol-gel matrix. The spectrofluorimetric response of dye-doped tetraethyl ortosilicate (TEOS) film after exposure to certain concentrations of K+ has been investigated, and 62% of relative signal change was achieved. The dynamic working range of the sensor membrane has been found between 10–9 and 10–6 M K+, in other terms from nanomolar to micromolar levels, which is an advantage over flame emission spectroscopy, in view of detection limit. The sensor is fully reversible within the dynamic range and the response time (90) is found to be 2 min under batch conditions. The cross-sensitivity of the molecule to Na+, Ba2+, Ca2+, and NH+
4 was also tested in separate solutions. 相似文献
968.
R. Erdem 《The European Physical Journal C - Particles and Fields》2002,25(4):623-628
We give a simple model to explain the origin of fermion families and chirality through the use of a domain wall-anti-domain
wall pair placed in a five dimensional space-time.
Received: 14 March 2002 / Revised version: 3 July 2002 / Published online: 27 September 2002
RID="a"
ID="a" e-mail: erdem@likya.iyte.edu.tr 相似文献
969.
The electronic energy-band structure, density of states (DOS), and optical properties of AgBO3 in the paraelectric cubic phase have been studied by using density functional theory within the local density approximation
for exchange-correlation for the first time. The band structure shows a band gap of 1.533 eV (AgNbO3)and 1.537 eV (AgTaO3)at (M-⌈)point in the Brillouin zone. The optical spectra of AgBO3 in the photon energy range up to 30 eV are investigated under the scissor approximation. The real and imaginary parts of
the dielectric function and — thus the optical constants such as reflectivity, absorption coefficient, electron energy-loss
function, refractive index, and extinction coefficient — are calculated. We have also made some comparisons with related experimental
and theoretical data that is available.
相似文献
970.