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Filippov V.V.,B. I. Stepanov Institute of Physics | Shulitskii B.G.,Belorussian State University of Information Science and Radioelectronics
Journal of Applied Spectroscopy | Year: 2010

We show that the spectral position of the maxima in the exciton generation rate G in a photovoltaic cell, taking into account the spectral energy distribution in the AM1. 5G solar spectrum, is determined by the absorption bands of its donor and acceptor materials. It varies slightly as the thicknesses of the layers in the cell change. Interference of light affects only the magnitude of these maxima. For a cell based on a CuPc (copper phthalocyanine)-C60 (fullerene) heterojunction, the G maxima are located at 640 nm, 720 nm (absorption in CuPc) and close to 495 nm (absorption in C60). The photovoltaic cell can be optimized using the ratio of the magnitudes of these maxima and their variations as layer thicknesses are varied and the exciton diffusion length is taken into account. © 2010 Springer Science+Business Media, Inc.


Bodnar' I.V.,Belorussian State University of Information Science and Radioelectronics | Pavlyukovets S.A.,Belorussian State University of Information Science and Radioelectronics | Danilchik A.V.,B. I. Stepanov Institute of Physics | Lutsenko E.V.,B. I. Stepanov Institute of Physics
Journal of Applied Spectroscopy | Year: 2011

We have used the Bridgman method to grow single crystals of the ternary compound FeIn2Se4 and we have determined their composition and structure. We measured the transmission spectra in the intrinsic absorption edge region in the temperature range 20-300 K. From the transmission spectra, we determined the bandgap width and plotted its temperature dependence. We show that the Eg(T) dependence has a shape typical for semiconductor compounds. © 2011 Springer Science+Business Media, Inc.


Kupreeva O.V.,Belorussian State University of Information Science and Radioelectronics | Lazarouk S.K.,Belorussian State University of Information Science and Radioelectronics | Borisenko V.E.,Belorussian State University of Information Science and Radioelectronics | Kun L.,ogical University | Kang T.B.,ogical University
Journal of Applied Spectroscopy | Year: 2013

We describe a process for obtaining tubular nanostructured (nanotubular) titanium oxide by electrochemical anodizing. We have studied the elemental composition of the films formed by x-ray spectral analysis and Auger analysis, and have also studied the photocatalytic properties of TiO2 exposed to UV and visible radiation. © 2013 Springer Science+Business Media New York.


Gurskii A.L.,Belorussian State University of Information Science and Radioelectronics | Peuneva N.A.,Belorussian State University of Information Science and Radioelectronics
Journal of Applied Spectroscopy | Year: 2013

We propose a method for eliminating the interference pattern from optical spectra, letting us improve the accuracy in determining the spectral function. The method is based on formal replacement of the energy argument in the spectral function by a temporal argument, followed by Fourier transformation to the frequency domain. In the frequency representation obtained, the frequency region corresponding to the contribution from the interference pattern is filtered out, and then the shape of the spectrum is recovered by an inverse Fourier transformation and replacement of the argument. We give a criterion for applicability of the method to real optical spectra. © 2013 Springer Science+Business Media New York.


Petruk V.G.,Vinnytsia National Technical University | Ivanov A.P.,B. I. Stepanov Institute of Physics | Kvaternyuk S.M.,Vinnytsia National Technical University | Barun V.V.,B. I. Stepanov Institute of Physics | Barun V.V.,Belorussian State University of Information Science and Radioelectronics
Journal of Applied Spectroscopy | Year: 2016

Experimental data on the spectral dependences of the optical diffuse reflection coefficient for skin from different people with melanoma or nevus are presented in the form of the probability density of the diffuse reflection coefficient for the corresponding pigmented lesions. We propose a noninvasive technique for differentiating between malignant and benign tumors, based on measuring the diffuse reflection coefficient for a specific patient and comparing the value obtained with a pre-set threshold. If the experimental result is below the threshold, then it is concluded that the person has melanoma; otherwise, no melanoma is present. As an example, we consider the wavelength 870 nm. We determine the risk of malignant transformation of a nevus (its transition to melanoma) for different measured diffuse reflection coefficients. We have studied the errors in the method, its operating characteristics and probability characteristics as the threshold diffuse reflection coefficient is varied. We find that the diagnostic confidence, sensitivity, specificity, and effectiveness (accuracy) parameters are maximum (> 0.82) for a threshold of 0.45-0.47. The operating characteristics for the proposed technique exceed the corresponding parameters for other familiar optical approaches to melanoma diagnosis. Its distinguishing feature is operation at only one wavelength, and consequently implementation of the experimental technique is simplified and made less expensive. © 2016 Springer Science+Business Media New York.

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