A Rapid, Nondestructive Method of Precision Oxygen Analysis by Neutron Activation.

Abstract

A new, highly automated method of elemental analysis for oxygen is described. The method represents an improvement over previous techniques

Activation analysis with charged particles

“…This can be partially overcame, by spinning the targets (both sample and standard) (12). In thermal neutron activation, there is also the problem of trace impurities having very high cross-sections.…”

Accelerator Systems for Activation Analysis—A Comparative Survey

“…A number of different methods have been used to compare flux differences on samples and standards. These include the use of BF3 counters [8], plastic scintillators [14], and the monitoring of N 16 aCtivity in target-cooling water [15]. Another approach, the reference-sample technique, has been developed, which attempts to eliminate the need for directly monitoring the neutron flux by irradiating the sample and standard simultaneously in a dual transfer system.…”

“…However, it does not provide an indication of differences in effective neutron flux due to flux attenuation in the sampIe, a source of error which becomes quite important for large samples or for samples containing elements with large neutron cross sections. To account for self-shielding effects, Anders [14] developed a flux monitor consisting of a small, plastic scintillator bead mounted on a photomultiplier tube. This detector is mounted in the geometrical shadow of the sample and monitors the neutron flux passing through the sample.…”

“…A number of systems designed to control the irradiation and transfer of samples, both single [8,14,15], and dual [16][17][18], have been described in the literature. These systems generally consist of plastic or metal tubing, in which the sample is transferred between the accelerator and counting rooms by compressed gas or a vacuum, along with the controls necessary to regulate and measure the irradiation time, delay time, and counting time.…”

Large sample neutron activation analysis avoids representative sub-sampling and sample preparation difficulties: An added value for forensic analysis

“…As such, neutron activation products can be measured in objects with dimensions of several kilograms. Anders and Briden [9] described the measurement of Oxygen in 60 g steel samples; Kim et.al. described the analysis of 250-500 mL water samples [10] and many mining and exploration companies use NAA in well-logging tools [11].…”