Determination of OH-groups concentration, and point defects in lithium niobate crystals.

The analysis of structural particularities of nominally pure and doped LiNbO3single crystals was performed by methods of Raman light scattering and infrared absorption. The concentration of OH groups, as well as the concentration of point defects is calculated from IR absorption spectra in the region of stretching vibrations of OH groups. A correlation has been determined in behavior of IR absorption spectra bands of strongly doped LiNbO3:Zn crystals with the behavior of the Raman spectra band that correspondsto stretching bridge vibrations of oxygen atoms in octahedra along the polar axis.

Additive Approach to Simulation of Malignant Neoplasms Using the Monte Carlo Method

The paper is devoted to additive simulation of Raman light scattering by skin cancer using the Monte Carlo method. Raman light scattering from normal skin, malignant melanoma and basal cell carcinoma is investigated. Based on the photon transport algorithm proposed by L. Wang and S. L. Jacques, a two-stage algorithm for simulating Raman light scattering from skin has been developed. A method for additive modeling of skin pathologies is proposed. The main idea of this method is a hypothesis that an experimental Raman spectrum of normal skin, obtained by averaging in vivo Raman spectra of normal skin, may be served as a “substrate” for the feature simulated Raman spectrum. Thus, the pathology, for their part, may be “grown” by adding on this “substrate” Raman specific components set related to a tumor type. Additive simulation of malignant melanoma on various stages and basal cell carcinoma has been carried out. The possibility of using the developed algorithm to determine the component composition of the skin by the in vivo Raman spectrum of skin is discussed. An attempt to evaluate the change in the concentration of skin components during the development of cancer has been made.

RADIATION-INDUCED GROWTH EPITAXIAL CASI2 FILM

In this work investigated crystal structure of films formed by molecular beam epitaxy (MBE) of CaSi2 on Si (111), under electron irradiation by the method of Raman light scattering (RS), it was found that a CaSi2 film is formed at the interface between the silicon substrate and the epitaxially growing CaF2 film under the influence of an electron beam.