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Article
A characterization of the Grassmann embedding of H(q), with q even
In this note, we characterize the Grassmann embedding of H(q), q even, as the unique full embedding of H(q) in PG(12, q) for which each ideal line of H(q) is contained in a plane. In particular, we show that no s...
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Article
Neutron spectrum calibration using the Cd-ratio for multi-monitor method with a synthetic multi-element standard
Several methods are in use for the determination of the thermal to epithermal neutron fluence rate ratio (f) and the deviation of the epithermal neutron spectrum from the 1/E shape parameter (α). In our former wo...
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Article
Regular partitions of (weak) finite generalized polygons
In this paper we define a regular m-partition of a distance regular graph as a partition of the vertex set into m classes, such that the number of vertices of a given class adjacent to a fixed vertex of another c...
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Article
Preparation and characterization of loess sediment for use as a reference material in the annual radiation dose determination for luminescence dating
Loess sediment was prepared and characterized with well-established K, Th and U contents, and corresponding 40K, 232Th and 235,238U activities, intended for use as a reference material in the annual radiation dos...
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Article
Radon loss from encapsulated sediments in Ge gamma-ray spectrometry for the annual radiation dose determination in luminescence dating
In Ge gamma-ray spectrometry for the annual radiation dose determination in the luminescence dating of sediments, the picture of 226Ra enrichment or depletion (in the 238U decay series) obtained via measurement o...
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Article
Radon loss from encapsulated sediments in Ge gamma-ray spectrometry for the annual radiation dose determination in luminescence dating
In Ge gamma-ray spectrometry for the annual radiation dose determination in the luminescence dating of sediments, the picture of 226Ra enrichment or depletion (in the 238U decay series) obtained via measurement o...
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Article
Codes from Generalized Hexagons
In this paper, we construct some codes that arise from generalized hexagons with small parameters. As our main result we discover two new projective two-weight codes constructed from two-character sets in PG(5,4)...
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Article
The use of a Zr-Au-Lu alloy for calibrating the irradiation facility in k0-NAA and for general neutron spectrum monitoring
The use of a Zr-Au-Lu alloy allows the simultaneous determination of all neutron spectrum parameters relevant to the k-0standardization of NAA, in terms of both the Høgdahl and the Westcott convention. The presen...
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Article
A performance comparison of k0-based ENAA and NAA in the (K, Th, U) radiation dose rate assessment for the luminescence dating of sediments
Recently, in our laboratory an intercomparison was made of methods for the annual radiation dose determination (assessed from direct radiation counting and/or from the measurement of the K, Th and U contents) ...
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Article
The effect of different sample-calibrant composition in gamma-ray spectrometry for the assessment of the radiation dose rate in the luminescence dating of sediments
One of the basic steps in luminescence dating is the determination of the annual radiation dose. Among the suitable determination methods in the case of sediment dating is HPGe gamma-ray spectrometry, primaril...
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Article
A Distance-2-Spread of the Generalized Hexagon H(3)
In this paper, we construct a distance-2-spread of the known generalized hexagon of order 3 (the split Cayley hexagon H(3)). Furthermore we prove the uniqueness of this distance-2-spread in H(3) and show that it...
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Article
The performance of k0-INAA in recent exercises on the certification of rare earth elements in bio-environmental materials
The performance of k 0-INAA was studied for the determination of the rare earth elements (plus Th and U) in the certification of four new BCR CRM's: 667 Estuarine Sediment, 690 Calcareous Soil, 67...
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Article
Recalibration of the irradiation facilities in the Thetis reactor, with an examination of the a versus E behavior in the keV neutron energy range
The reloading of research reactor Thetis (INW, Gent), in April 1996, involved the re-calibration of the irradiation facilities used for k 0-NAA. In some channels, the values of the re-measured parameters f and a ...
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Article
Introduction of Marinelli effective solid angles for correcting the calibration of NaI(Tl) field gamma-ray spectrometry in TL/OSL dating
A study is made of the corrections that are needed in the evaluation of the annual radiation dose, for use in TL/OSL-dating, via NaI(Tl) field gamma-ray spectrometry (monitoring of K, Th and U), calibrated via...
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Article
Some irregularities observed in the analysis results of k0-NAA
Since 1996, two new cases were detected in our laboratory for which the elemental concentrations derived from k 0 neutron activation analysis seem questionable. These cases concern the inconsistencies observed (1...
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Article
Evaluation of Three Software Programs for Calculating True-Coincidence Summing Correction Factors
True-coincidence summing correction is an essential element in k 0-based NAA1 and becomes important when samples are counted with a high efficiency detector. This may be the case where large detectors are used or...
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Article
The installation of KAYZERO-assisted NAA for use in industry and environmental sanitation in three Central European countries: Plans and achievements of a COPERNICUS project
At the “Special Sessionk 0” of the MTAA-8 (Vienna, 1991), and later on at the “Intemationalk 0 Users Workshop-Gent” (1992), progress was reported with respect to the development and use of computer codes in order...
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Article
Loss-free counting in NAA using KAYZERO evaluation software
To account for varying dead time (frequently occurring when the measuring time is comparable with the half lives of the radionuclides in question) the use of Westphal's Loss-Free Counting technique (LFC) is pr...
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Article
A dedicated NAA method to determine the neutron spectrum monitor elements Co, Au and Lu with high accuracy in alloyed wires and foils
A dedicated NAA calibration method was developed for the determination of the neutron spectrum monitor elements Co, Au and Lu in alloyed wires and foils, with an accuracy of better than 1%. The method does not...
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Article
Nuclear data and measurements for the130Ba(n,γ)131Ba reaction
Although k0-factors and related nuclear data for 122 radionuclides of interest in (n,γ) reactor neutron activation analysis have been tabulated, there are still some reactions attracting interest with respect to ...
