Radioisotopic neutron transmission spectrometry: Quantitative analysis by using partial least-squares method.
Neutron spectrometry, based on the scattering of high energy fast neutrons from a radioisotope and slowing-down by the light hydrogen atoms, is a useful technique for non-destructive, quantitative measurement of hydrogen content because it has a large measuring volume, and is not affected by temperature, pressure, pH value and color. The most common choice for radioisotope neutron source is (252)Cf or (241)Am-Be. In this study, (252)Cf with a neutron flux of 6.3x10(6)n/s has been used as an attractive neutron source because of its high flux neutron and weak radioactivity. Pulse-height neutron spectra have been obtained by using in-house built radioisotopic neutron spectrometric system equipped with (3)He detector and multi-channel analyzer, including a neutron shield. As a preliminary study, polyethylene block (density of approximately 0.947g/cc and area of 40cmx25cm) was used for the determination of hydrogen content by using multivariate calibration models, depending on the thickness of the block. Compared with the results obtained from a simple linear calibration model, partial least-squares regression (PLSR) method offered a better performance in a quantitative data analysis. It also revealed that the PLSR method in a neutron spectrometric system can be promising in the real-time, online monitoring of the powder process to determine the content of any type of molecules containing hydrogen nuclei.
Kim
Jong-Yun
JY
Nuclear Chemistry Research Division, Korea Atomic Energy Research Institute, 150 Dukjin-dong Yuseong-gu, Daejeon 305-353, Republic of Korea. kjy@kaeri.re.kr
Choi
Yong Suk
YS
Park
Yong Joon
YJ
Jung
Sung-Hee
SH
D002138:Calibration; D002142:Californium; D004867:Equipment Design; D006859:Hydrogen / Q000032:analysis*; D016018:Least-Squares Analysis; D009502:Neutrons; D011868:Radioisotopes; D013057:Spectrum Analysis / Q000295:instrumentation* / Q000379:methods
D011868:Radioisotopes; D006859:Hydrogen; D002142:Californium