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Chisinau, Moldova

The Moldova State University is a university located in Chişinău, Moldova. It was founded in 1946. Wikipedia.

Chirita A.,Moldova State University
Journal of Modern Optics | Year: 2010

The processes of micro-object hologram real-time recording on a photo-thermo-plastic carrier based on a chalcogenide glassy semiconductor As-Se-S-Sn system were studied. The possibility to measure micro-object dimensions using an interference fringe pattern was shown. Double-exposure hologram recording by use of photo-induced structural transformation processes in a photo-semiconductor and photo-thermoplastic recording process was investigated. © 2010 Taylor & Francis.

Seremet V.,Moldova State University
Engineering Analysis with Boundary Elements | Year: 2010

In this paper the functions of influence of unit point heat source onto displacements and Poisson-type integral formula for a boundary value problem (BVP) in thermoelastic half-space, free of loadings on the boundary plane are presented in closed form. The thermoelastic displacements are generated by heat source applied at the inner point of the half-space and by heat flux, prescribed on its boundary. All these results are formulated in a special theorem. Furthermore, the advantages and usefulness of the obtained results are also discussed. The main difficulties to obtain such kind of results are to derive the functions of influence of a unit concentrated force onto elastic volume dilatation Θ(k) and Green's functions in heat conduction G. For canonical Cartesian domains, these difficulties were addressed successfully, and the above-mentioned functions were derived and published earlier. Thus, it can be presumed that for the Cartesian domains, this paper will open a great possibility to derive new thermoelastic influence functions and Poisson's integral formulas in closed form. Moreover, the technique proposed here will also work for any orthogonal canonical domain, as soon as the lists of functions G and Θ(k) are completed. © 2009 Elsevier Ltd. All rights reserved.

Seremet V.,Moldova State University
Acta Mechanica | Year: 2014

This paper is devoted to a new approach for the derivation of main thermoelastic Green's functions (MTGFs), based on their new integral representations via Green's functions for Poisson's equation. These integral representations have permitted us to derive in elementary functions new MTGFs and new Poisson-type integral formulas for a thermoelastic octant under mixed mechanical and thermal boundary conditions, which are formulated in a special theorem. Examples of validation of the obtained MTGFs are presented. The effectiveness of the obtained MTGFs and of the Poisson-type integral formula is shown on a solution in elementary functions of a particular BVP of thermoelasticity for octant. The graphical and numerical computer evaluation of the obtained MTGFs and of the thermoelastic displacements of the particular BVP for an octant is also presented. By using the proposed approach, it is possible to derive in elementary functions many new MTGFs and new Poisson-type integral formulas for many canonical Cartesian domains. © 2013 Springer-Verlag Wien.

Balandin A.A.,University of California at Riverside | Nika D.L.,University of California at Riverside | Nika D.L.,Moldova State University
Materials Today | Year: 2012

Phonons - quanta of crystal lattice vibrations - reveal themselves in all electrical, thermal, and optical phenomena in materials. Nanostructures open exciting opportunities for tuning the phonon energy spectrum and related material properties for specific applications. The possibilities for controlled modification of the phonon interactions and transport - referred to as phonon engineering or phononics - increased even further with the advent of graphene and two-dimensional van der Waals materials. We describe methods for tuning the phonon spectrum and engineering the thermal properties of the low-dimensional materials via ribbon edges, grain boundaries, isotope composition, defect concentration, and atomic-plane orientation. © 2012 Elsevier Ltd.

Nika D.L.,University of California at Riverside | Nika D.L.,Moldova State University | Balandin A.A.,University of California at Riverside
Journal of Physics Condensed Matter | Year: 2012

Properties of phonons - quanta of the crystal lattice vibrations - in graphene have recently attracted significant attention from the physics and engineering communities. Acoustic phonons are the main heat carriers in graphene near room temperature, while optical phonons are used for counting the number of atomic planes in Raman experiments with few-layer graphene. It was shown both theoretically and experimentally that transport properties of phonons, i.e.energy dispersion and scattering rates, are substantially different in a quasi-two-dimensional system such as graphene compared to the basal planes in graphite or three-dimensional bulk crystals. The unique nature of two-dimensional phonon transport translates into unusual heat conduction in graphene and related materials. In this review, we outline different theoretical approaches developed for phonon transport in graphene, discuss contributions of the in-plane and cross-plane phonon modes, and provide comparison with available experimental thermal conductivity data. Particular attention is given to analysis of recent results for the phonon thermal conductivity of single-layer graphene and few-layer graphene, and the effects of the strain, defects, and isotopes on phonon transport in these systems. © 2012 IOP Publishing Ltd.

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