Prompt gamma-ray analysis of chlorine in superpozz cement concrete

Neutron-Stimulated Gamma Ray Analysis of Soil

“…State-of-the-art nuclear physics methodologies and instrumentation, combined with commercial availability of portable pulse neutron generators, high-efficiency gamma detectors, reliable electronics, and measurement and data processing software, have currently made the application of neutron-gamma analysis possible for routine measurements in various fields of study. For these reasons, material analysis using characteristic gamma rays induced by neutrons is more wide-spread today; e.g., threat material detection (explosives, drugs, and dangerous chemicals [1]), diamond detection [2], planetary science applications for obtaining bulk elemental composition information, soil elemental (isotopic) content and density distribution [3], archaeological site surveying and provenance studies [4,5], elemental composition of human [6,7] and animal [8,9] bodies, real-time elemental analysis of bulk coal on conveyor belts [10,11], chloride content of reinforced concrete [12,13], and in oil well logging [14].…”

Chlorine signal attenuation in concrete

“…The intensity of 6.11 MeV chlorine gamma-ray was measured from a rack containing nine concrete slabs each measuring 8 in  8 in  1 in stacked together using a portable neutron generator based PGNAA setup. The PGNAA setup used in this study is a modified form of the PGNAA setup described in other publications of the authors (Naqvi et al, 2012(Naqvi et al, , 2014. The PGNAA setup utilized in the reported study mainly consists of a portable neutron generator, a cylindrical 25 cm  8 cm (diameter  height) density polyethylene (HDPE) moderator and nine rectangular, 20 cm  20 cm  2.5 cm concrete slabs stacked together in a rack.…”

“…Then one chlorinated contaminated SF cement concrete slab specimen was prepared by mixing 3% chloride ion, by weight of the cementitious material, following the procedure described elsewhere (Naqvi et al, 2012(Naqvi et al, , 2014.Then, one of the uncontaminated SF cement concrete slab specimen was replaced by the contaminated SF cement concrete slab. Initially, the contaminated SF cement concrete slab was placed touching the moderator, at a distance of 1.25 cm between the moderator surface and the chlorinated SF concrete slab center.…”

“…The typical beam current of the generator was 55-65 μA. The thermal neutron spectra were acquired in PC-based data acquisition system utilizing multichannel buffer module Model 920E-16, ETHERNIM using a cylindrical 52 mm diameter and 2 mm thick enriched-Lithium glass thermal neutron detector, as described previously (Naqvi et al, 2012). The Li-glass was placed at 30°angle to neutron generator axis at a distance of 180 cm from the target plane location.…”

“…Due to high capture cross section of thermal neutrons in chlorine, nuclear techniques, particularly Prompt Gamma Neutron Activation (PGNAA), offer a prompt and reasonably accurate method to asses chlorine contamination in concrete. Recently, an accelerator based-PGNAA setup has been developed successfully to determine the chloride concentration in concrete (Naqvi et al, 2012(Naqvi et al, , 2014. The portable neutron generator based PGNAA setup developed by the authors in a previous study has been utilized to measure the intensity of chloride gamma-ray intensity emitted from various depths in silica fume (SF) cement concrete.…”