Articolele autorului SIMONA CONDURACHE-BOTA
Link la profilul stiintific al lui SIMONA CONDURACHE-BOTA

Clouds blown by the solar wind

In this letter we investigate possible relationships between the cloud cover (CC) and the interplanetary electric field (IEF), which is modulated by the solar wind and the interplanetary magnetic field. We show that CC at mid–high latitudes systematically correlates with positive IEF, which has a clear energetic input into the atmosphere, but not with negative IEF, in general agreement with predictions of the global electric circuit (GEC)-related

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Temperature dependence of the optical properties of Bi2O3. A theoretical approach based on the Kramers-Kronig transformation for polynomial mixed terms models

The Kramers-Kronig transforms (KK) constitute a powerful tool to validate experimental data. The present study is implemented for Bi2O3 thin films deposited by thermal vacuum evaporation at different temperatures of the glass substrates. Since the extraordinary properties of this fabric allow us to consider particular analytical approach as it was previously shown, the reflectance properties of Bi2O3 as a function of temperature could be studied.

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Polynomial fitting approach for the Kramers–Kronig method for optical properties computing for Bi2O3 fabric

The optical reflectance of Bi2O3 was measured, and the optical properties were estimated by Kramers–Kronig analysis. The novelty of the present study is due to the implementation of a MAPLE software approach to the complex computations implied by this extrapolation. The analytical fit of the reflectance spectrum is applied, accompanied by a careful extrapolation, which is necessary within the Kramers–Kronig method. In this way starting from the

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The influence of substrate temperature on the structure and on the optical reflection spectrum of bismuth thin films

Thin films of pure bismuth were deposited by vacuum thermal evaporation onto glass substrates maintained at different temperatures: 27 deg. C, 50 deg. C, 100 deg. C, 150 deg. C and 200 deg.C, respectively. The structure of the obtained films was analyzed by means of X-ray Diffractometry, with a Shimadzu diffractometer, which operates with a Cu target. The XRD patterns corresponding to a wide angular range proved the polycrystallinity of the bismuth

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Optical and Electrical Properties of Thermally-Oxidized Bismuth Thin Films

Bismuth trioxide (Bi2O3) thin films were prepared by dry thermal oxidation of metallic bismuth films deposited by vacuum evaporation. The oxidation process of Bi films consists of a heating from the room temperature to an oxidation temperature (To = 673 K), with a temperature rate of 8 K/min; an annealing for 1 h at oxidation temperature and, finally, a cooling to room temperature. The optical transmission and reflection spectra of the films were

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Complex analysis of the bells’ sounds from the ‘Saint Trinity’ Cathedral from Alba Iulia

The analysis of the sounds emitted by the new system of bells from the Saint Trinity Cathedral of Alba Iulia, Romania was performed and compared to a witness sound, by means of complex acoustic analysis programs called Wavanal and Sigview. The study of the partials influence on the amplitude, intensity and, inherently the pitch of the resulting sounds emitted by the bells system is also considered. The change in time of the partials intensity and

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Temperature correction for thickness measurements of hot rolled steel plates

Measuring the thickness of steel plates during the hot rolling process is crucial for getting the necessary feedback to obtain the desired values at room temperature. The dilatation and the phase transformations of steel occur during heating and subsequent cooling and rolling strongly influences the results of thickness measurements. The radiometric method provides the necessary means for making real-time and fully automatized measurements of steel

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Important physical parameters of Bi2O3 thin films found by applying several models for optical data

Different optical parameters for thin solid films can be computed as functions of wavelength from the optical transmission and reflection spectra. Subsequently, several models can be tested on the obtained data, in order to check their validity with respect to the materials under study. Moreover, these models offer the possibility to estimate essential physical parameters. Such models are tested within this article for the refraction index and for

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Influence of the conditions of the thermal treatment on the electrical properties of Cobalt oxide layers

The influence of thermal treatment (different annealing atmospheres) on the electrical properties of cobalt oxide thin layers was studied. The layers were fabricated by sol-gel technique. Electrical properties were determined by the four–point probe method and Van der Pauw technique. The film resistivity decreases with temperature which confirms the semiconductor nature of the film. For the same film thickness value, the layers exposed in air exhibit

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Structural and optical analysis of superimposed bismuth and antimony oxides

Bismuth trioxide and antimony trioxide were deposited by thermal vacuum evaporation one on top of the other. The temperature of the substrate during deposition was maintained at 20 deg. C, 70 deg. C and 120 deg. C, respectively. Also, the deposition order of the two oxides was reversed, in order to find if there is any change in the properties of the entire two oxides structure. Their structural characteristics were studied by means of X-ray diffraction

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