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91.
In the last years, there has been great interest to the formulation and application of wavelet transformation in variety of fields to investigate the characteristics of dynamical systems. Recently, a method based on the scalogram analysis of the continuous wavelet transform, the scale index has been proposed to measure aperiodicity and determine the transitions from aperiodic behaviour to periodic behaviour in nonlinear dynamical systems. In this work we test the scale index method by performing the analysis of the deterministic behaviour of the fermion-like two-dimensional Akdeniz–Smailagic instanton solution in Thirring Model. We show that the scale index method can also be considered to detect the periodic behaviours of the fermion-like instanton solutions. 相似文献
92.
Thickness and composition of thin films can be measured with X- and gamma-rays. In this work, thickness and composition of vanadium pentoxide thin films are investigated by energy dispersive and wavelength dispersive X-ray fluorescence systems. Also, the surface analysis of vanadium pentoxide thin films irradiated with Rhodium Kα X-rays and 59.54?keV gamma-rays emitted from 100?mCi and 5?Ci Americium-241 radioactive sources is performed by scanning electron microscope. It is observed that X- and gamma-rays are destructive for vanadium pentoxide thin films. Also, the composition of vanadium pentoxide thin films changes by irradiation with X- and gamma-rays. 相似文献
93.
In this study, (Bi2O3)1?x?y(Sm2O3)x(CeO2)y ternary system was synthesized by using solid-state reaction method. Structural, morphological, thermal and electrical properties of the samples were evaluated by means of X-ray diffraction (XRD), scanning electron microscopy, thermo gravimetry/differential thermal analyzer and four-probe method. The XRD measurement results indicated that the samples (x = 10–15, y = 5–10–15–20) had cubic δ-phase crystallographic structure. The phase stability of the samples was checked by the differential thermal analyzer measurements, which indicates most of the samples have stable δ-Bi2O3 phase. The electrical conductivity measurement results showed that the electrical conductivity increased with mol% CeO2 molar ratio at a fixed molar ratio of Sm2O3. The highest electrical conductivity obtained for the (Bi2O3)0.65(Sm2O3)0.15(CeO2)0.20 system was 1.55 × 10?2 (Ω.cm)?1 at 600 °C. The activation energies were also calculated at low temperature range (350–650 °C) which vary from 1.1325 to 1.4460 eV and at high temperature (above 650 °C) which vary from 0.4813 to 1.1071 eV. 相似文献
94.
Alper Tolga ?olak G?nül Pamuk Okan Zafer Ye?ilel Filiz Y?lmaz Orhan Büyükgüng?r 《Journal of chemical crystallography》2012,42(1):76-82
Abstract
The [Co(H2O)6][Co(pydc)2(en)]2·14H2O (1) compound (H2pydc = Pyridine-2,3-dicarboxylic acid and en = ethylenediamine) was synthesized and characterized by elemental analysis, magnetic and spectroscopic measurements (UV–Vis and IR spectra) and single crystal X-ray diffraction technique. There are two coordination spheres with different charges inside this aqueous compound of ionic character. The cationic part is composed of Co(II) encircled by six aqua ligand. Whereas the anionic part contains two anions complex unit each with −1 charge and have Co(III) ions in the centre. As a result different coordination spheres have cobalt ions with different states. The crystallographic analysis revealed that 1 consists of both discrete one-cationic and two-anionic entities, [Co(H2O)6]2+ and [Co(pydc)2(en)]2− and fourteen crystal water molecules. Two water molecules within the water cluster act as hydrogen-bonding acceptors, whereas one water molecule acts as a hydrogen-bonding donor to form a discrete water trimer. These water molecules have stabilized the crystal structure by strong hydrogen bonding interactions. 相似文献95.
A very special case of one of the theorems of the authors states as follows: Let 1a
1a
2... be an infinite sequence of integers for which all the sumsa
i
+a
j
, 1ij, are distinct. Then there are infinitely many integersk for which 2k can be represented in the forma
i
+a
j
but 2k+1 cannot be represented in this form. Several unsolved problems are stated.Dedicated to our friend Professor E. Hlawka on the occasion of his seventieth birthday 相似文献
96.
A Sárközy 《Journal of Number Theory》1985,20(1):70-80
It is a well-known conjecture that (n2n) is never squarefree if n > 4. It is shown that (n2n) is not squarefree if n > n0. 相似文献
97.
The solvability of the equation a1a2 … ak = x2, a1, a2, …, ak ε
is studied for fixed k and ‘dense’ sets
of positive integers. In particular, it is shown that if k is even and k 4, and
is of positive upper density, then this equation can be solved. 相似文献
98.
99.
3-Aminoquinazolinone–phosphine proligands (5a–e) and their Ru(II) complexes (6a–e) were prepared and characterized by NMR (1H, 13C, 31P{1H}), FTIR and microanalysis. The 3-aminoquinazolinone–phosphine ligands were found to coordinate with the Ru(II) center via their phosphorus and nitrogen atoms. The Ru(II) complexes were applied as catalysts for the hydrogenation and transfer hydrogenation of prochiral ketones. The results showed that these complexes are efficient transfer hydrogenation catalysts. 相似文献
100.
The retention of various radionuclides on metal sulphide precipitates has been studied. The sulphide precipitates quantitatively retained the common radionuclides. The condition for 100% retention in a thin layer is small particle size (a few μm) in the precipitate. This can be ensured by pulverization of the dried precipitate of metal sulphide. 203Hg2+ is retained by mercury sulphide and 65Zn2+ by zinc sulphide by isotopic exchange. The retention of foreign radioactive ions can be reduced or even eliminated by counter-carrier technique in cases where the retention is not due to chemical reaction, precipitate exchange. The isotopic exchange with mercury(II) sulphide and zinc sulphide enables mercury and zinc ions to be separated rapidly and determined in the presence of a number of interfering ions. 相似文献