On the trail of short-lived neutron activation products

Journal Article · Tue Dec 31 04:00:00 EST 1996 · Transactions of the American Nuclear Society

OSTI ID:426293

Chatt, A

Instrumental neutron activation analysis (INAA) is perhaps the most widely used nondestructive analytical technique for the simultaneous measurement of trace and ultratrace concentrations of a number of elements in a variety of complex sample matrices. There are many advantages with INAA, which include analysis without physical destruction of a sample, freedom from reagent blanks, minimal handling of samples prior to irradiation, virtual freedom from matrix interference, applicability to samples of all three physical states, qualitative as well as quantitative analysis, capability to determine almost all elements, multielement specificity, very high sensitivity and low detection limits, extensive linear range, and excellent precision and accuracy. In general, the INAA methods reported in the literature involve the use of fairly long lived nuclides, which require lengthy irradiation, decay, and counting periods resulting in long turnaround times and high cost of analysis. The total experimental time for routine analysis of many elements by INAA can be significantly reduced by employing short-lived nuclides. The conventional INAA technique involving a one-shot irradiation-decay-counting scheme can also be used for detecting short-lived nuclides. However, both precision and sensitivity of measurement can be drastically improved by using methods based on the principles of cyclic activation. In cyclic INAA (CINAA), a sample is irradiated for a short time followed by its rapid transfer to a detector for counting for a short period. This irradiation-decay-counting process is immediately repeated for an optimum number of cycles in CINAA. On the other hand, if several days are allowed to elapse between the repetition of the irradiation-decay-counting cycles, then the technique is termed pseudo-cyclic INAA (PCINAA). Advantages and implementations of these schemes are described.

• OSTI ID: 426293
• Report Number(s): CONF-961103--
• Journal Information: Transactions of the American Nuclear Society, Journal Name: Transactions of the American Nuclear Society Vol. 75; ISSN TANSAO; ISSN 0003-018X
• Country of Publication: United States
• Language: English

Related Subjects

40 CHEMISTRY
MINUTES LIVING RADIOISOTOPES
NEUTRON ACTIVATION ANALYSIS
SECONDS LIVING RADIOISOTOPES