จำนวน Repository ( 2 )
Comparison alpha and gamma spectrometry method for the determination of pb-210 in freshwater sediment
The comparison of methodology from and -spectrometry methods has been made for freshwater sediment. The differences of precisions 18% and 15% were found for ? and -ray spectrometry respectively. Results from the analysis of certified reference materials (IAEA-326 327) showed good agreement with recommended values and data available in the literature. Thus an alternative methodology based on alpha/gamma activity ratio was developed and tested using different samples. The method is based on the determination of total -activity (46.53 keV peak associate with Pb-210) and the total -activity present in the aliquot. Differences between methods could be caused by different behaviors of Pb-210 and Po-210 (used for alpha measurement) in the freshwater sediment. In gamma spectrometry errors may arise when many gamma emitters are measured simultaneously and their activity peaks overlap. In alpha spectrometry chemical separation of Po-210 may result in analytical error due to incomplete sample dissolution. Pb-210 activities derived by alpha and gamma methods are shown to agree within counting error. The inherent compatibility of analytical results based on alpha or gamma techniques is established. Nevertheless the choice of an alternate method to determine the freshwater sediment criteria to time comfortable convenient and budget.
Determination of metals in some thai tradition medicines using inductively coupled plasma–optical emission spectrometry (ICP-OES)
This research work aims to analyse of metals in thai tradition medicines using Inductively Coupled Plasma–Optical Emission Spectrometry (ICP-OES). The sample groups were divided into four catagories which were Snuff balsam gentian violet and drug pickled liquor. Six metals Aluminium (Al) Cadmium (Cd) Chromium (Cr) Copper (Cu) Magnesium (Mn) and Lead (Pb) were studied. In Snuff the amount of Al was in the range of ND-0.017 ppm the amount of Cd was in the range of ND-0.017 ppm the amount of Cr was in the range of 0.041-0.173 ppm the amount of Cu was in the range of ND-0.244 ppm Moreover Mn content was in the range of 0.633-2.384 ppm. In the case of balsam the amount of Al was in the range of 0-0.575 ppm the amount of Cd was in the range of ND-0.004 ppm the amount of Cr was in the range of 0.025-0.570 ppm the amount of Mn was in the range of 0.460-0.754 ppm whilst none of Cu and Pb was detected. In the case of gentian violet the amount of Cr was in the range of 0.033-0.063 ppm the amount of Mn was in the range of 0.165-0.543 ppm whilst none of Al Cd Cu and Pb was detected. In the case of medicine pickled the amount of Cr was in the range of ND-0.058 ppm the amount of Mn was in the range of ND-0.264 ppm the amount of Ni was in the range of 0-0.034 ppm no metals Al Cd Cu and Pb was observed. The detected metals in thai tradition medicines have the contamination value under the optimization scale for consumable under WHO. It show that some metals were retained in thai tradition medicines and the contamination level of metals in were acceptable.