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51.
We have theoretically investigated two-dimensional atom localization using the absorption spectra of birefringence beams of light in a single wavelength domain.The atom localization is controlled and modified through tunneling effect in a conductive chiral atomic medium with absorption spectra of birefringent beams.The significant localization peaks are investigated in the left and right circularly polarized beam.Single and double localized peaks are observed in different quadrants with minimum uncertainty and significant probability.The localized probability is modified by controlling birefringence and tunneling conditions.These results may be useful for the capability of optical microscopy and atom imaging. 相似文献
52.
Sibel Irmak Kemal Solakyildirim Arif Hesenov Oktay Erbatur 《Journal of Analytical Chemistry》2010,65(9):899-906
The aim of this study was to examine the influence of storage conditions and duration on composition and antioxidant activity
of supercritical fluid (SCF) extracted essential oil of rosemary (Rosmarinus officinalis L.). Supercritical extraction was carried out sequentially by using SCF carbondioxide in the first two steps and with 5%
ethanol as entrainer in the third step. The compositions of the extracts were determined by gas chromatography/mass spectrometry.
The total phenolics were analyzed using Folin-Ciocalteau assay. Antioxidant activities of the extracts were tested by β-carotene-linoleic
acid bleaching method. 相似文献
53.
In laser cutting of sheet metals, thermal stresses are developed in the region of the cutting section. Depending on the cutting conditions and substrate material properties, the thermal stress levels can attain high values. In the present study, thermal stress developed in the region of the laser cut edges is modeled and temperature as well as stress fields are predicted. Temperature predictions are validated through the experimental results. It was found that the temporal variation of the maximum temperature along y-axis follows the laser heating source. However, temporal variation of von-Mises stress deviates slightly from the temporal variation of temperature along the cutting direction. Increase in scanning speed enhances the von-Mises stress levels due to the attainment of high temperature gradients in the substrate material. 相似文献
54.
BaMnO3 nanorods were synthesized at 200 °C and atmospheric pressure using the composite-hydroxide mediated method. X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy were used to investigate the structure, size, morphology, phase purity and elemental composition of BaMnO3 nanorods. Electrical characterization of BaMnO3 pellet was performed at 300-400 K and in the frequency range 200 Hz-2 MHz. Temperature dependence of AC conductivity suggests that the BaMnO3 pellet behaves as a semiconducting material and conduction across the pellet can be explained by the correlated barrier hopping model. Impedance analysis was performed using the equivalent circuit model (R1Q1C1)(R2C2) and it suggests a single relaxation process in the BaMnO3 pellet at a particular temperature. The analysis reveals that the BaMnO3 pellet behaves like an n-type semiconductor material due to the presence of oxygen vacancies and some disorder. Modulus spectroscopy also supports the impedance results. 相似文献
55.
Arif D. SheikhAbdulsamee Fawzi V.L. Mathe 《Journal of magnetism and magnetic materials》2011,323(6):740-747
We present systematic studies that comprise phase connectivity and dielectric, multiferroic (MF) and magnetoelectric (ME) properties of (x) Ni0.8Co0.2Fe2O4+(1−x) Pb(Mg1/3Nb2/3)0.67Ti0.33O3 [where x=0.15, 0.30 and 0.45] ME composites prepared by conventional solid-state reaction method. Scanning electron microscopic images of the composites predict different types of connectivity schemes viz 3-0, 3-1 and 3-3. The phase transition temperature of PMN-PT is independent of Ni0.8Co0.2Fe2O4 content. Room temperature P-E and M-H loops indicate the simultaneous existence of ferroelectric/magnetic ordering. In order to study the possibility of monitoring electrical ordering by means of a magnetic field, ME measurements were carried out. The composition-dependent phase connectivity was well co-related to formation of percolation path and inturn magnetoelectric output. 相似文献
56.
Ljubomir iri Arif Rafiq Nenad Caki 《Nonlinear Analysis: Theory, Methods & Applications》2009,70(12):4332-4337
In this note, we speed up the convergence of the Picard sequence of iterations for strongly accretive and strongly pseudo-contractive mappings. Our results improve the results of Chidume [C.E. Chidume, Picard iteration for strongly accretive and strongly pseudo-contractive Lipschitz maps, ICTP Preprint no. IC2000098; C.E. Chidume, Iterative Algorithms for Non-expansive Mappings and Some of Their Generalizations, in: Nonlinear Analysis and Applications: To V. Lakshmikantham on his 80th Birthday, vol. 1, 2, Kluwer Acad. Publ, Dordrecht, 2003, pp. 383–429], and Liu [L. Liu, Approximation of fixed points of a strictly pseudo-contractive mapping, Proc. Amer. Math. Soc. 125 (2) (1997) 1363–1366], and some other known results. The technique of the proof, presented in this paper, is different from the technique used by Chidume. 相似文献
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Methods of processing iron-manganese concretions from the Gulf of Finland in the Baltic Sea are reported. The relative content
of their basic components is found. The concentration of helium isotopes in and the rate of growth of these concretions (7.5
mm/thousand years) are determined. It is shown that the content of the cosmic matter in the concretions can be raised by means
of special chemical processing. 相似文献