JOPSS - Search Results

Journal Articles

Analysis of uranium distribution in rocks by -PIXE

Onuki, Toshihiko; Kozai, Naofumi; Samadfam, M.; Yasuda, Ryo; Kamiya, Tomihiro; Sakai, Takuro; Murakami, Takashi*

Nuclear Instruments and Methods in Physics Research B, 181(1-4), p.586 - 592, 2001/07

https://doi.org/10.1016/S0168-583X(01)00381-0

Times Cited Count：14 Percentile：68.91(Instruments & Instrumentation)

no abstracts in English

Journal Articles

High-sensitivity detection of fissile materials in a waste dram by direct interrogation of 14MeV acc neutrons

Haruyama, Mitsuo; Ara, Katsuyuki*; Takase, Misao*

Nihon Genshiryoku Gakkai-Shi, 43(4), p.397 - 404, 2001/04

https://doi.org/10.3327/jaesj.43.397

Times Cited Count：3 Percentile：27.07(Nuclear Science & Technology)

no abstracts in English

JAEA Reports

Measurement of neodymium(III) and samarium(III) by spectrophotometer and laser-induced photoacoustic spectroscopic system: A Preliminary study for speciation of aqueous Np(IV) species.

Kitamura, Akira; *

JNC TN8400 2001-009, 54 Pages, 2001/01

JNC-TN8400-2001-009.pdf:1.3MB

Spectroscopic measurements of neodymium(III) and samarium(III) were carried out by spectrophotometer and laser-induced photoacoustic spectroscopic (LPAS) system for the investigation of the detection limit of both systems. The absorption spectra and photoacoustic spectra of Nd $^{3+}$ and Sm $^{3+}$ were obtained with varying the concentration of the ions from 210 $^{-5}$ to 210 $^{-2}$ moldm $^{+3}$ . The absorption spectrum of Nd $^{3+}$ was also determined by a special spectrophotometer, of which the measurement cell was set in a glove box filled with inert nitrogen gas. For the comparison with these photoacoustic and absorption spectra, the absorption spectra of Nd $^{3+}$ and Sm $^{3+}$ were determined by an usual spectrophotometer with the light-path lengths of 1 cm and 10 cm. The detection limit of the photoacoustic measurement was reported much lower than that of absorbance measurement by several researchers. However, the present study was concluded that the detection limit of photoacoustic measurement with the present LPAS system was similar to that of absorbance measurement with the light-path length of 10 cm. The detection limits of neptunium(IV,V) were estimated and the possibility of the speciation of neptunium(IV) was discussed from the results of the present study.

JAEA Reports

Demonstration study on shielding safety analysis code (VII)

Sawamura, Sadashi*

JNC TJ8400 2000-053, 41 Pages, 2000/02

JNC-TJ8400-2000-053.pdf:1.6MB

Dose evaluation for direct radiation and skyshine from nuclear fuel facilities is one of the environment evaluation items. This evaluation is carried out by using some shielding calculation codes. Because of extremely few benchmark data of skyshine, the calculation has to be performed very conservatively. Therefore, the benchmark data of skyshine and the well-investigated code for skyshine would be necessary to carry out the rational evaluation of nuclear facilities. The purpose of this study is to obtain the benchmark data of skyshine and to investigate the calculation code for skyshine. In this fiscal year, the followings are investigated; (1)To improve the detection sensitivity of pulsed neutron measurement, two neutron detectors and some electronic circuits are added to the system constructed last year. (2)To estimate the neutron dose at the distant point from the facility instead of the commercialized rem-counter, a $^{3}$ He detector with paraffin moderator is equipped to the system. (3)Using the new detection system, the skyshine of neutrons from 45Mev LINAC facility was measured in the distance up to 300m. The results show that the time structure of pulsed neutrons almost disappears at the further points than 150m. (4)In the distance from 90m to 300m ordinal total counting method without gate pulse are applied to detect the neutrons. (5)The experimental results of space dependency up to 300m is fitted fairly well by the Gui's response function.

JAEA Reports

An experimental study of sodium aerosol detection sensitivity by laser induced breakdown spectroscopy

;

JNC TN9400 2000-020, 54 Pages, 1999/11

JNC-TN9400-2000-020.pdf:2.36MB

A Laser-induced breakdown spectroscopy Leak Detection technique (abbreviated LLD) of sodium is accomplished by plasmafying the sodium aerosol, and then selectively detecting the sodium specific optical spectrum. This method is potentially more reliable as a means of detecting of sodium small leakage. This report, describes test results of detection characteristics using sodium aerosol, carried out to verify the principle of LLD in addition to evaluating the response under various conditions. 0ur main objective is to examine the applicability of LLD for small sodium leakage. The main results are as follows; (1)We confirmed the principle of LLD, specifically detecting the sodium optical spectru.m. (2)The relation between LLD fluorescence intensity and sodium aerosol concentration is nearly proportional within a relatively Na concentration ranges 10 $^{-11}$ 10 $^{-8}$ g/cm $^{3}$ . (3)The LLD signal appeared insensitive to the effect of sampling gas flow rate, oxygen concentration, and humidity in the examined range. ln fact, a high S/N ratio is obtained for small sodium leakage, and the reliability of the leakage detection is high, because LLD showed sensitive to sodium concentration. From these results and others discussed in this report, LLD appears to be an applicable technique in small leakage detection both in terms of response and reliabilily in the leakage phase.