Measurement of reflection coefficients of organic and non-organic media and materials in UV spectrum

Measurements of the diffuse reflection coefficients of organic and inorganic materials and media in solid, granular and liquid forms were made in the UV field of 230–400 nm. A single channel spectrometer with an integrating sphere was used. Relation between diffuse reflection coefficients and the structure and composition of the samples is discussed. These data allow us to estimate the prospect of machine vision systems application for the UV range in such areas as biology, geology, remote control of materials and media

Study of electronic properties of transition metals and alloys by positron annihilation spectroscopy

Section V. Equipment, Methods and Automation of Nuclear Experiments, Interaction of Nuclear Radiation with the Matter and Applications of Methods of Nuclear Physic

Study of electronic properties of transition metals and alloys by positron annihilation spectroscopy

Section V. Equipment, Methods and Automation of Nuclear Experiments, Interaction of Nuclear Radiation with the Matter and Applications of Methods of Nuclear Physic

Onset of Soret-induced convection in a horizontal layer of ternary fluid with fixed vertical heat flux at the boundaries

The paper deals with the investigation of the onset and weakly nonlinear regimes of the Soret-driven convection of ternary liquid mixture in a horizontal layer with rigid impermeable boundaries subjected to the prescribed constant vertical heat flux. It is found that there are monotonous and oscillatory longwave instability modes. The boundary of the monotonous longwave instability in the parameter plane Rayleigh number Ra - net separation ratio $\Psi$ at fixed separation ratio of one of solutes consists of two branches of hyperbolic type. One of the branches is located at ${\rm Ra} >0$, the other one at ${\rm Ra} 0$ only for the heating from below and at $\Psi 0$ and the other at ${\rm Ra} <0$. Corrections to the Rayleigh number obtained in the higher order of the expansion show that the longwave perturbations can be most dangerous at any values of $\Psi$. The numerical solution of the linear stability problem for small perturbations with finite wave numbers confirms this conclusion. The weakly nonlinear analysis shows that all steady solutions are unstable to the modes of larger wavelength and stable to the modes of smaller wavelength, i.e. the solution with maximal possible wavelength is realized

Measurement of reflection coefficients of organic and non-organic media and materials in UV spectrum

Measurements of the diffuse reflection coefficients of organic and inorganic materials and media in solid, granular and liquid forms were made in the UV field of 230–400 nm. A single channel spectrometer with an integrating sphere was used. Relation between diffuse reflection coefficients and the structure and composition of the samples is discussed. These data allow us to estimate the prospect of machine vision systems application for the UV range in such areas as biology, geology, remote control of materials and media

Positronics and Nanotechnologies - Possibilities of Studying Nanoobjects in Materials and Nanomaterials by the Method of Positron-Annihilation Spectroscopy

The method of positron-annihilation spectroscopy is shown to be one of the most efficient methods for determining sizes of nanoobjects (vacancies, vacancy clusters); free volumes of pores, cavities, and hollows; and their concentrations and chemical composition at the point of annihilation in porous systems and some defective materials (and generally in a lot of technologically important materials and nanomaterials). Experimental investigations of nanodefects in porous silicon, silicon, and quartz single crystals irradiated with protons and in quartz powders are briefly reviewed.JRC.F.5-Safety of present nuclear reactor