Search Results

You are looking at 1 - 3 of 3 items for :

  • Author or Editor: K. Kis x
  • Chemistry and Chemical Engineering x
  • Refine by Access: All Content x
Clear All Modify Search

Abstract  

The results from numerous intercomparison exercises and proficiency tests indicate that the measurement of 90Sr in solid environmental matrices poses a problem to many analysts. The causes of the observed scatter of analytical results are not well understood and therefore difficult to remedy. In order to assess the effect of various analytical operations and measurement routines on the quality of the 90Sr data, the IAEA's Analytical Control Services have organised a proficiency test using a mineral sample spiked at three different levels with known amounts of 90Sr. This proficiency test generated considerable interest from the radioanalytical community as a total of 192 sets of samples were distributed to 158 radioanalytical laboratories world-wide. The reported data were evaluated with respect to their relative bias against the reference value and with respect to their reported overall uncertainty. The major sources of bias leading to overestimated values are ineffective purification procedures, high background values and a lack of statistical control over background values. The major sources of bias leading to an underestimation are overestimated recovery factors in part due to failure to correct for stable Sr in the sample and possibly failure to correct for quenching in liquid scintillation counting. Preliminary results for a small randomly selected group of laboratories are presented.

Restricted access

Winter wheat (Triticum aestivum L.) yield samples taken from a consecutive series of crop years representing drought, normal and moist conditions at the Nagygombos experimental site of the Szent István University have been evaluated. The impact of N topdressing and crop year conditions on the performance of protein and wet gluten content were studied.The results suggest that ascending levels of N topdressing, and increased number of applications had a beneficial effect on the protein content, as well as on wet gluten values. Crop year had a significant effect on quality manifestation. The drier the crop year, the better the recorded quality performance. The magnitude of changes was bigger in case of gluten than in that of protein values. There were minor differences between the two varieties examined, especially in their response patterns to nitrogen supply. Dough formation depends mainly on the gliadin/ glutenin ratio, but there is less information on the agronomic and climatic impacts that may cause alterations in that.

Restricted access
Journal of Radioanalytical and Nuclear Chemistry
Authors:
Zs. Kasztovszky
,
Z. Kis
,
T. Belgya
,
W. Kockelmann
,
S. Imberti
,
G. Festa
,
A. Filabozzi
,
C. Andreani
,
A. Kirfel
,
K. Biró
,
K. Dúzs
,
Zs. Hajnal
,
P. Kudejova
, and
M. Tardocchi

Abstract  

The aim of the ‘Ancient Charm’ project is combining neutron tomography, prompt gamma activation analysis, time of flight neutron diffraction and neutron resonance transmission to generate elemental, and phase compositions of complex museum objects in 3D. To develop a protocol for such investigations, complex test samples were constructed and then analyzed by each method. The ‘black boxes’ are sealed iron and aluminum walled cubes, containing 2D or 3D arrangements of materials relevant for the compositions of archaeological samples. The experimental results obtained from bulk PGAA at BNC and TOF-ND at ISIS on two selected boxes are reported.

Restricted access