3,050 research outputs found

    On increasing of the competitiveness of the garment industry in Siberian Federal District on the basis of the industrial cluster establishment

    Full text link
    The issue of the development prospects of the Russian economy and the economy of its individual branches in the regions is highly relevant in terms of the increasing crises and economic development challenges. The scope of the study is a garment industry of the Siberian Federal District, which includes 12 subjects, and only six of them develop the garment industry actively. There are the regions of Kemerovo, Novosibirsk, Omsk, Tomsk, Krasnoyarsk Krai and the Republic of Khakassia. The subject matter of the research is the state and prospects of the garment industry of the Siberian Federal District. It also includes the assessment of the garment industry as one of the sub-sectors of the light industry in terms of its competitiveness in the domestic market. The purpose of the comprehensive study is to determine the conditions and factors affecting the development of the industry, as well as to identify its development reserves and competitiveness on the basis of industrial cluster’s generation. The hypothesis of this study is that in the Siberian Federal District, there are a need and reserves to create a cluster of the garment industry. The main methods of the study are the comparative analysis, the expert assessment of the sector in certain regions of the Siberian Federal District, as well as the assessment of possible formation of the industrial cluster in the region. The results of the study are the evaluation of the competitiveness and prospects of the garment industry in Russia and the Siberian Federal District (a low level of development and competitiveness); the evaluation of the development level of the garment industry in the Federal District, which have showed the demand for apparel products from the population and enterprises, as well as the conditions for the provision of clothing manufacture with natural fabrics and synthetic materials, labor resources and research and development achievements; also the justification of the existing potential for development of a sectoral cluster by means of pooling together the productions and economic communications of the Novosibirsk and Omsk regions at the initial stage. The obtained results should be used to strengthen works for the development of regional industrial cluster (with a creation of a working group at the regional governments, the garment industry development programs, and practical measures for its realization), as well as a creation of conditions for stimulation of investment activity of entrepreneurs. The research has confirmed the hypothesis, that in the Siberian Federal District, there are a need and reserves to create a cluster of the garment industry

    Ground state of the holes localized in II-VI quantum dots with Gaussian potential profiles

    Full text link
    We report on the theoretical study of the hole states in II-IV quantum dots of a spherical and ellipsoidal shape, described by a smooth potential confinement profiles, that can be modelled by a Gaussian functions in all three dimensions. The universal dependencies of the hole energy, gg-factor and localization length on a quantum dot barrier height, as well as the ratio of effective masses of the light and heavy holes are presented for the spherical quantum dots. The splitting of the four-fold degenerate ground state into two doublets is derived for anisotropic (oblate or prolate) quantum dots. Variational calculations are combined with numerical ones in the framework of the Luttinger Hamiltonian. Constructed trial functions are optimized by comparison with the numerical results. The effective hole gg-factor is found to be independent on the quantum dot size and barrier height and is approximated by simple universal expression depending only on the effective mass parameters. The results can be used for interpreting and analyzing experimental spectra measured in various structures with the quantum dots of different semiconductor materials.Comment: 13 pages, 8 figure

    Anisotropy of effective masses in CuInSe2

    Get PDF
    Anisotropy of the valence band is experimentally demonstrated in CuInSe2, a key component of the absorber layer in one of the leading thin-film solar cell technology. By changing the orientation of applied magnetic fields with respect to the crystal lattice, we measure considerable differences in the diamagnetic shifts and effective g-factors for the A and B free excitons. The resulting free exciton reduced masses are combined with a perturbation model for non-degenerate independent excitons and theoretical dielectric constants to provide the anisotropic effective hole masses, revealing anisotropies of 5.5 (4.2) for the A (B) valence bands

    Exciton spin dynamics and photoluminescence polarization of CdSe/CdS dot-in-rod nanocrystals in high magnetic fields

    Full text link
    The exciton spin dynamics and polarization properties of the related emission are investigated in colloidal CdSe/CdS dot-in-rod (DiR) and spherical core/shell nanocrystal (NC) ensembles by magneto-optical photoluminescence (PL) spectroscopy in magnetic fields up to 15 T. It is shown that the degree of circular polarization (DCP) of the exciton emission induced by the magnetic field is affected by the NC geometry as well as the exciton fine structure and can provide information on nanorod orientation. A theory to describe the circular and linear polarization properties of the NC emission in magnetic field is developed. It takes into account phonon mediated coupling between the exciton fine structure states as well as the dielectric enhancement effect resulting from the anisotropic shell of DiR NCs. This theoretical approach is used to model the experimental results and allows us to explain most of the measured features. The spin dynamics of the dark excitons is investigated in magnetic fields by time-resolved photoluminescence. The results highlight the importance of confined acoustic phonons in the spin relaxation of dark excitons. The bare core surface as well as the core/shell interface give rise to an efficient spin relaxation channel, while the surface of core/shell NCs seems to play only a minor role.Comment: 18 pages, 15 figure

    Change in radio sensitivity of mice under effect of rotation

    Get PDF
    Radiosensitivity of animals placed in slowly rotating chambers was investigated and was found to vary under the influence of the functional load on the vestibular analyzer. An increased radioresistance was registered in populations of the most radiosensitive mice. In populations of more radioresistant animals the gravitational load decreases the radioresistance
    corecore