| Title | Prompt gamma neutron activation analysis of SRMS at the McMaster Nuclear Reactor in 1990 and the future prospects |
| Download | Download (whole publication) |
| Author | Shaw, D M; Smith, P L C |
| Source | GEOANALYSIS 90, an international symposium on the analysis of geological materials; by Hall, G E M (ed.); Geological Survey of Canada, Bulletin 451, 1993 p. 64-65, https://doi.org/10.4095/193293 |
| Year | 1993 |
| Publisher | Natural Resources Canada |
| Meeting | GEOANALYSIS 90; Huntsville, Ontario; CA; June 3-7 1990 |
| Document | serial |
| Lang. | English |
| Media | paper |
| Related | This publication is contained in Hall, G E M; (1993).
GEOANALYSIS 90, an international symposium on the analysis of geological materials, Geological Survey of Canada, Bulletin no. 451 |
| Subjects | geochemistry; analytical methods; chemical analysis; neutron activation analysis |
| |
| Released | 1994 01 01 |
| Abstract | The 2 Mw McMaster Nuclear Reactor has operated a thermalized neutron beam with a dedicated prompt gamma neutron activation analysis (PGNAA) system for about six years, for determination mostly of B, but
also for Gd, Sm, and H. The horizontal neutron beam is filtered through silicon and sapphire, giving a flux of 6 x 107nþcm-2þs-1 with a Cd ratio >100 at the sample position, 250 cm from the reactor core. Samples are irradiated in Teflon or
polyethylene capsules which can hold up to 7 g of powder and gamma rays are received in an Aptec 12% efficient intrinsic Ge detector connected with standard multichannel counting equipment. The usual peaks are: B 478 keV, Gd 182 keV, Sm 334 and 439
keV, H 2223 keV. The blank signals from an empty capsule correspond to sensitivity limits of: B 0.4 þg, Gd 0.2 þg, Sm 0.4 þg, H 100 þg. The system is calibrated using appropriate pure chemicals, deposited from solution in a base of silica powder.
Precision is monitored by repeat measurements and averages 3-5% (1 standard deviation) for all four elements, except for concentrations near the detection limits. Accuracy is surveyed by including two or more SRMs in each analysis batch. In most
cases our results of repeated analysis of many SRMs show agreement with results from other laboratories, using other methods. If present plans can be carried out, the reactor will be retrofitted with a new core, using the so-called MAPLE design. This
will increase the power to 12 Mw and, in addition, the enhanced thermal neutron flux will be generated using a methane cold source. The sensitivity of PGNAA will increase by several orders of magnitude. |
| GEOSCAN ID | 193293 |
|
|