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CdTe films with different compositions (Cd-rich, Te-rich and stoichiometric) were fabricated by a novel and low cost chemical molecular beam deposition method (CMBD) in atmospheric pressure hydrogen flow. Cd and Te granules were used as precursors. The films were deposited on ceramic (Si[O.sub.2]:[Al.sub.2][O.sub.3]) substrates at 580[degrees]C and 600[degrees]C. The growth rate was varied in the range of 9-30 [Angstrom]/s. The composition (Cd/Te) of the samples was changed by controlling the molecular beam intensity (MBI) ratio. Three samples fabricated at MBI ratios Cd/Te = 0.5, 1.0 and 1.16 were investigated by XRD, AFM, EDX, SEM, photoluminescence (PL) and Hall methods. Keywords: CdTe; Photoluminescence; Resistivity; Chemical molecular beam deposition; Thin film

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.solener.2005.04.022 Byline: Yu. Vorobiev (a), J. Gonzalez-Hernandez (b), P. Vorobiev (c), L. Bulat (d) Keywords: Photovoltaic panel; Energy flux concentrator; Heat engine; Thermoelectric generator Abstract: A hybrid solar system with high temperature stage is described. The system contains a radiation concentrator, a photovoltaic solar cell and a heat engine or thermoelectric generator. Two options are discussed, one with a special PV cell construction, which uses the heat energy from the part of solar spectrum not absorbed in the semiconductor material of the cell; the other with concentration of the whole solar radiation on the PV cell working at high temperature and coupled to the high temperature stage. The possibilities of using semiconductor materials with different band gap values are analyzed, as well as of the different thermoelectric materials. The calculations made show that the proposed hybrid system could be practical and efficient. Author Affiliation: (a) CINVESTAV-Queretaro, Libramiento Norponiente 2000, Queretaro 76230, Queretaro, Mexico (b) CIMAV, Miguel de Cervantes 120, Chihuahua 31109, Mexico (c) Facultad de Ingenieria, Universidad Autonoma de Queretaro, Queretaro, Mexico (d) St. Petersburg State University of Refrigeration and Food Engineering, St. Petersburg 191002, Russia Article History: Received 1 November 2004; Revised 13 April 2005; Accepted 18 April 2005 Article Note: (miscellaneous) Communicated by: Associate Editor Xavier Matthew

We present a detailed analysis of the orbital stability of the Pais-Uhlenbeck oscillator, using Lie-Deprit series and Hamiltonian normal form theories. In particular, we explicitly describe the reduced phase space for this Hamiltonian system and give a proof for the existence of stable orbits for a certain class of self-interaction, found numerically in previous studies, by using singular symplectic reduction. [ABSTRACT FROM AUTHOR]

An experimental model of a solar hybrid system including photovoltaic (PV) module, concentrating Fresnel lens, thermoelectric generator (TEG), and running water heat extracting unit was created and studied. The PV module used was of c-Si and TEG of Bi2Te3; the Fresnel lens (solar concentrator) and TEG share an optical train, whereas PV module was illuminated separately with non-concentrated light. Heat extracting unit operated in thermo siphon mode. In climatic conditions of Mexico (Queretaro, 20o of North latitude, summer time), the Fresnel lens accepted 120 W of solar radiation power, and the system generated 7.0 W of electric power and 30 W of thermal one. The discussion is made of the possible characteristics of a hypothetical hybrid system where all its elements share the same optical train. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

We present a coordinate-free approach for constructing approximate first integrals of generalized slow-fast Hamiltonian systems, based on the global averaging method on parameter-dependent phase spaces with S1-symmetry. Explicit global formulas for approximate second-order first integrals are derived. As examples, we analyze the case quadratic in the fast variables (in particular, the elastic pendulum), and the charged particle in a slowly-varying magnetic field. [ABSTRACT FROM AUTHOR]

This paper reports the coefficients CA,B for the k-linear term in dispersion relation E(k) for holes of the upper valence bands Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. in p-CuInSe2 crystals. We also obtained the tensor components for the carrier effective masses Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. in all three valence sub-bands of the model semiconductor. It was shown that the energy spectrum parameters for holes in CuInSe2 allow successful explanation for the anisotropy of tensor components describing the interband light absorption coefficient and the published data for the temperature variation of the Hall coefficient, total Hall mobility and thermal voltage within the temperature range 100 K ≤ T ≤ 350 K. [ABSTRACT FROM AUTHOR]

Electronic spectra of nine different types of organic colorants embedded in three different matrices (sol–gel SiO2 , PMMA, and SiO2–PMMA) were studied experimentally with the use of optical absorption, photoluminescence excitation, and emission techniques, as well as fluorescent microscopy and atomic force microscopy. We found a distinct set of energy levels for each type of dye. The type of matrix and the degree of aggregation of the organic molecules have relatively small effects on the spectra, although their influence on the optical density of the material is essential. The character of the energy spectra is mainly related with the shape of the dye molecule. A quantum mechanical description of the electronic spectra of these molecules was made on the basis of the free electron molecular orbitals approach. The molecules were considered as two-dimensional potential wells with different shapes. The effect of boundary conditions on the energy spectra was studied. The direct solution of the Schrödinger equation shows a good theory–experiment correlation. [ABSTRACT FROM AUTHOR]

In the given paper, the results are presented of the investigation of non-equilibrium stationary carders system in semiconductor under photo-Gunn effect. It was found that spacehomogeneous state of the system is unstable in the case of negative differential conductivity and two waves of space-time perturbations with different phase velocities propagate through the crystal. Phase velocity degeneration conditions have been determined for these waves. Dependence of the complex attenuation decrement on external influences (electric field tension, incident light intensity, semiconductor compensation degree and spectral range) has been investigated in details. State dynamics of inhomogeneous carder system has been studied using synergetics methods. Obtained results prove that one can controllably switch between the oscillation states of electron subsystem by changing the incident light intensity. [ABSTRACT FROM AUTHOR]

This paper reports the coefficients CA,B for the k-linear term in dispersion relation E(k) for holes of the upper valence bands Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. in p-CuInSe2 crystals. We also obtained the tensor components for the carrier effective masses Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. in all three valence sub-bands of the model semiconductor. It was shown that the energy spectrum parameters for holes in CuInSe2 allow successful explanation for the anisotropy of tensor components describing the interband light absorption coefficient and the published data for the temperature variation of the Hall coefficient, total Hall mobility and thermal voltage within the temperature range 100 K ≤ T ≤ 350 K. [ABSTRACT FROM AUTHOR]

Abstract: New results on quasi-free η photoproduction on the neutron and proton bound in a deuteron target are presented. The quasi-free cross section reveals a bump-like structure which is not seen in the cross section on the proton. This structure may signal the existence of a relatively narrow (, ) baryon state. [Copyright &y& Elsevier]