Authors:Eveline De Robertis, Gabriela F. Moreira, Raigna A. Silva, and Carlos A. Achete
for thermal behavior studies, since by the standard method for such determinations the major drawback is the time of analysis.
In this work, our intention is verify the thermal behavior of two standardreferencematerials (SRM) using DSC, such
INAA results of 11 standard reference materials used in archaeometric investigations of pottery as well as in environmental analysis are presented. The values obtained for 24 elements are compared with the certificate values as well as with the analytical data of other investigators. The accuracy of analysis is discussed.
Three standard reference materials were analyzed by a method of absolute INAA. Two different light water pool-type reactors
were used to produce equivalent analytical results even though the epithermal to thermal flux ratio in one reactor was higher
than that in the other by a factor of two.
A procedure for monostandard INAA of 21 elements (Hg, As, Br, Cr, Sb, Se, Ba, Zn, Ca, Ce, Co, Cs, Eu, Fe, Hf, K, La, Rb, Sc, Sr, Ta) in Chinese Biological Standard Reference Material (peach leaves) is described. The accuracy of the procedure was checked by analyzing the U.S. NBS Standard Reference Materials SRM-1571 and SRM-1632a.
A routine procedure for monostandard INAA using short-lived radionuclides with half-lives from 2 min to 15 hrs is described. Ten elements (Al, Mg, Ti, V, Mn, Cl, Na, K. Br and Cu) are determined in Chinese Biological Standard Reference Material (peach leaves). The quality of analysis was checked by analyzing the U. S. NBS Standard Reference Materials SRM-1571 and SRM-1648.
Trace amounts of transition elements (Co, Cr, Cu, Fe, Mn and V) and other seven elements in optical waveguide samples were
determined by INAA. The contents of impurities in ultra-pure materials are less than those of high-purity materials and of
G.R. grade. The increase of contamination of trace transition elements and iridium from furnace or crucible are observed in
the production of optical glass fibers. Up to seventeen elements were determined in five NBS biological standard reference
materials: Oyster Tissue: SRM-1566, Brewers Yeast: SRM-1569, Spinach: SRM-1570, Orchard Leaves: SRM-1571 and Tuna Fish, and
in four Japanese biological standard reference materials: Tea Leaves B&C, Pepperbush and Shark Meat. The analytical results
in NBS and Japanese standard reference materials are in good agreement with published values and certified values by NBS.
The National Bureau of Standards has, for the past five years, been developing natural-matrix, environmental-level radioactivity Standard Reference Materials in large quantities to be available to users over a ten year time period. These materials have been found to be useful for the evaluation of radiochemical methods and analysis, as interlaboratory comparison materials, and as quality assurance materials. To date, six Standard Reference Materials have been issued: River Sediment, Human Lung, Human Liver, Rocky Flats Soil-1, Freshwater Lake Sediment, and Peruvian Soil. The concentrations of twenty radionuclides have been certified in these materials.
Instrumental neutron activation analysis (INAA) was used for the determination of 23 elements and prompt gamma neutron activation analysis (PGNAA) was used for the determination of 10 elements in U.S. National Bureau of Standards (NBS) 1633A Fly Ash Standard Reference Material (SRM). The results are in excellent agreement with the limited number of NBS certified values available.
A homogeneity test of 14 elements (Al, Cl, Mn, K, Ca, Ce, Th, Hf, Cs, Sc, Fe, Zn, Co and Eu) was made in Chinese Biological Standard Reference Material (peach leaves) by means of INAA. The procedures are described and the results are presented and discussed.