Using the Asymmetric Gaussian Method to Interpret the Electronic Spectroscopy of the Olivine Family

This paper discusses the mathematical aspects of band fitting and introduces the Asymmetric Gaussian curve and its tangent space for the first time. First, we derive an equation for an Asymmetric Gaussian shape. We then derive a rule for the resolution of two Gaussian shaped bands. We then use the Asymmetrical Gaussian equation to derive a Master Equation to fit two overlapping bands. We identify regions of the fitting space where the Asymmetric Gaussian fit is optimal, sub optimal and not optimal. We then demonstrate the use of the Asymmetric Gaussian curve to fit four overlapping Gaussian bands, and show how this is relevant to the olivine family spectral complex at 1 μm. We develop a modified model of the olivine family spectral complex based on previous work by Runciman and Burns. The limitations of the asymmetric band fitting method and a critical assessment of three commonly used numerical minimization methods are also provided.

METHODS FOR THE DETERMINATION OF SODIUM IN THE PROCESS OF WATER WASHING OF SALTY COAL

Coal with high content of alkaline and alkaline earth metals (salty coal) occupies its definite place in an energy reserve of the country. Standard methods to assess the dynamics of the release of salts (mainly sodium chloride) into the aqueous solution during the desalting of salty coal were used. The advantages and disadvantages of existing methods for determining the sodium content in aqueous solutions are considered. The principle of operation of the upgraded spectral complex KSVU-5 based on the determination of the content of alkali metals in aqueous solutions by the method of atomic emission analysis is presented. The remarkable reproducibility of the measurements results on the spectral complex of small and large concentration of Na in solution is shown. The results of an experimental study of the desalting process by water washing of salty coal samples of various size classes (in the range 0-5 mm) and analysis of the obtained solutions by the spectral complex KSVU-5 are presented. Comparison of the sodium concentration in solutions during the desalting of salty coal obtained by atomic absorption and atomic emission analysis was performed. The possibility of using express analysis (Conductivity/TDS) to determine the concentration of sodium in solution is shown. Ref. 8, Fig. 6.

Spectral deformation in a problem of singular perturbation theory

Quasi-classical asymptotic behavior of the spectrum of a non-self-adjoint Sturm–Liouville problem is studied in the case of a one-parameter family of potentials being third-degree polynomials. For this problem, the phase-integral method is used to derive quantization conditions characterizing the asymptotic distribution of the eigenvalues and their concentration near edges of the limit spectral complex. Topologically different types of limit configurations are described, and critical values of the deformation parameter corresponding to type changes are specified.

RESEARCH OF INFLUENCE OF SPECTRAL HINDRANCES ON RESULTS OF DEFINITION OF ELEMENTS FOR THE ATOMIC-ABSORPTION SPECTRAL ANALYSIS WITH CONTINUOUS SPECTRUM SOURCE

The traditional widespread method for the atomic-absorption spectral analysis (Walsh's method) now is consecutive since demands use of the selective light source and reorganization of wavelength of the monochromator for definition of each element as a part of test. This fact seriously reduces analysis productivity, however, this method almost completely excludes emergence of the problems connected with spectral hindrances. Using a method of the atomic-absorption spectral analysis with a continuous spectrum source and a spectrometer with low resolution for the simultaneous analysis of multielement samples, spectral hindrances of analytical lines of the elements which are contained in the analyzed substance are inevitable. For carrying out the correct qualitative and quantitative analysis it is necessary to identify, to divide and to consider spectral hindrances. In this work we presented application of a method of identification and accounting of spectral hindrances on a spectral complex of low resolution "Kolibri-AAS".

Lens-free Multi-Laser Spectral Light-Field Fusion Microscopy

<p>We present a device and method for performing lens-free spectral<br />light-field fusion microscopy at sub-pixel resolutions while taking<br />advantage of the large field-of-view capability. A collection of<br />lasers at different wavelengths is used in pulsed mode and enables<br />the capture of interferometric light-field encodings of a specimen<br />placed near the detector. Numerically fusing the spectral complex<br />light-fields obtained from the encodings produces an image of the<br />specimen at higher resolution and signal-to-noise-ratio while suppressing<br />various aberrations and artifacts.</p>