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[en] In this study K-beta/K-alpha (Kβ/Kα) intensity ratios of the elements scandium (Sc), vanadium (V), chromium (Cr), nickel (Ni), copper (Cu), zinc (Zn), bromine (Br), yttrium (Y), zirconium (Zr), and niobium (Nb) have been measured at three azimuthal scattering angles (+30o, 0o, and -30o) for two fixed polar scattering angles (85o and 135o). The elements were excited by 59.54 keV gamma photons emitted from 100 mCi Am241 point source. The obtained experimental values were compared with the theoretical values presented in the literature. It is observed that (Kβ/Kα) intensity ratios of the investigated elements do not depend on azimuthal angles at fixed polar angles. (author)
[en] Measurements of the rotational temperature of molecular nitrogen by emission spectroscopy were performed in a dc plasma torch of non-transferred arc operating at three different output powers. The band (0, 1) of the first negative system of N2+ (B2Σu+→X2Σg+) for the R branch was selected for these studies.
[en] In this work different projects in the field of inductively-coupled plasma optical emission spectrometry (ICP-OES) are presented. The first part deals with sample preparation. A new approach for microwave-assisted high pressure flow digestion was investigated and, in addition, diesel samples were digested using microwave-induced combustion for the subsequent determination of sulfur. In the second part a newly constructed optical interface for ICP-OES was designed which seals the plasma from the surroundings. This makes it possible to recycle part of the plasma gases leading to high savings of running costs. Furthermore, novel insights into the so-called 'carbon enhancement effect' are given. (author)
[en] Statistical uncertainty in the quantitative analysis of solid samples in motion by laser-induced breakdown spectroscopy (LIBS) has been assessed. For this purpose, a LIBS demonstrator was designed and constructed in our laboratory. The LIBS system consisted of a laboratory-scale conveyor belt, a compact optical module and a Nd:YAG laser operating at 532 nm. The speed of the conveyor belt was variable and could be adjusted up to a maximum speed of 2 m s-1. Statistical uncertainty in the analytical measurements was estimated in terms of precision (reproducibility and repeatability) and accuracy. The results obtained by LIBS on shredded scrap samples under real conditions have demonstrated that the analytical precision and accuracy of LIBS is dependent on the sample geometry, position on the conveyor belt and surface cleanliness. Flat, relatively clean scrap samples exhibited acceptable reproducibility and repeatability; by contrast, samples with an irregular shape or a dirty surface exhibited a poor relative standard deviation.
[en] The theory and mechanisms for spectroscopic observations of auroral arcs are examined. The emission rate ratios of various spectroscopic features are used to determine the average energy of the auroral particles, noting that only proton bombardment of the atmosphere can produce the observed emissions of atomic hydrogen, Balmer alpha, and Balmer beta. The atomic hydrogen particles can cause excitation, stripping, or ionization. Differences in subsequent electron observations due to the relative energy levels of the bombardment are described, and the use of the First Negative bands of molecular N ions and the ground configuration transition in singly atomic O for optical emission studies is outlined. The mean energy of the bombarding electron flux can be obtained and may be equalled under certain conditions by the proton flux. Finally, the characteristics of an ideal spectrometer for exploring auroral emissions are introduced
[en] The routine methods and the equipment used by the spectrochemical laboratory of the Nuclear Research Center of the Negev (NRCN) are described. The information is presented with the view to guiding the technicians of the laboratory in their work
[en] Thermoluminescence (TL) emission spectra have been obtained from alkali feldspars ranging from monoclinic and triclinic potassium-rich feldspars to tricline sodium-rich feldspars, as well as from a synthetic gel of KA1Si3O8 composition. Emissions were detected in the wavelength range 200-800 nm using a high sensitivity spectrometer. The results suggest that the 290 nm emission band in TL is associated either with the presence of crystalline phases of NaA1Si3O8 or with Na/K exsolution interfaces. (author)