• Title/Summary/Keyword: Swipe Sample

Search Result 5, Processing Time 0.016 seconds

Uranium Isotopic Ratio Analysis of U-Bearing Particulates By SIMS in CIAE

  • Yonggang, Zhao
    • Proceedings of the Korean Radioactive Waste Society Conference
    • /
    • 2004.02a
    • /
    • pp.257-259
    • /
    • 2004
  • In this paper measurement method of uranium isotope ratio of uranium-bearing particles in swipe samples was introduced; Swipe sample screening program was proposed on the basis of studying various destructive assay and non-destructive assays. Scanning electron microscope(SEM) equipped with an energy dispersive X-ray fluorescence(XRF) system was applied to locate the deposited uranium-containing particles on the graphite support, particle's composition and size can be identified. Some isotope ratio results were compared with those of other bulk analytical methods; By measuring the same prepared sample, we got the U-particle isotopic ratio data similar to those from IAEA NWAL, indicating that our operation parameters and experimental conditions are viable and can be used for measurement of U-particle isotopic ratio from swipe samples.

  • PDF

PRELIMINARY STUDY ON THE ALPHA TRACK ANALYSIS OF SPHERICAL URANIUM METAL PARTICLES

  • Pyo Hyung-Yeol;Kim Jong-Yun;Lee Myung-Ho;Park Yong-Jun;Jee Kwang-Yong;Kim Won-Ho
    • Nuclear Engineering and Technology
    • /
    • v.38 no.4
    • /
    • pp.353-358
    • /
    • 2006
  • Alpha track analysis for the determination of the trace amount of alpha emitting nuclides in a very small particle was performed as an efficient and powerful technique during safeguard inspection. Metal particles with well-defined spherical shape, size and isotopic compositions as a reference material were used to correlate the number of tracks or track diameter with an isotopic composition eventually to identify the uranium enrichment in the environmental swipe samples. Slopes in the number of tracks versus the exposure time curve provide a simple insight into the uranium enrichment of an unknown particle. Low enriched uranium metal particles result in slopes still steeper than the depleted or natural uranium metal particles. In addition, a linear relationship between track diameter and particle size Is thought to be a useful first stage analytical tool as an efficient and convenient inspection guide. The significance of the simple linear model was also judged using the usual statistical tests.

Performance Test of the Ultralow Background Gamma-Ray Measurement System (극저준위 백그라운드 감마선 측정시스템의 성능시험)

  • Na, Won-Woo;Lee, Young-Gil
    • Journal of Radiation Protection and Research
    • /
    • v.22 no.3
    • /
    • pp.219-226
    • /
    • 1997
  • Ultralow background gamma-ray measurement system was installed to measure and analyze gamma-rays emitted from environmental and swipe samples. The background reduction techniques applied on this system are the passive shielding to surround the HPGe detector, an active external anticosmic shield to shield cosmic-rays and the nitrogen gas supply to minimize the introduction of ubiquitous radon decay nuclei. The performance test result showed that the system background at energies between 50 keV and 2 MeV is reduced about $10^{-2}$ order and the MDA is so low as to be suitable for the environmental sample analysis. But it is appeared that the neutron produced by cosmic-ray increases the background at low energy region.

  • PDF

Improvement of Measurement Precisions for Uranium Isotopes at Ultra Trace Levels by Modification of the Sample Introduction System in MC-ICP-MS

  • Park, Ranhee;Lim, Sang Ho;Han, Sun-Ho;Lee, Min Young;Park, Jinkyu;Lee, Chi-Gyu;Song, Kyuseok
    • Mass Spectrometry Letters
    • /
    • v.7 no.2
    • /
    • pp.50-54
    • /
    • 2016
  • Multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) is currently used in our laboratory for isotopic and quantitative analyses of nuclear materials at ultra-trace levels in environmental swipe samples, which is a very useful for monitoring undeclared nuclear activities. In this study, to improve measurement precisions of uranium isotopes at ultratrace levels, we adopted a desolvating nebulizer system (Aridus-II, CETAC., USA), which can improve signal sensitivity and reduce formation of uranium hydride. A peristaltic pump was combined with Aridus-II in the sample introduction system of MC-ICP-MS to reduce long-term signal fluctuations by maintaining a constant flow rate of the sample solution. The signal sensitivity in the presence of Aridus-II was improved more than 10-fold and the formation ratio of UH/U decreased by 16- to 17- fold compared to a normal spray chamber. Long-term signal fluctuations were significantly reduced by using the peristaltic pump. Detailed optimizations and evaluations with uranium standards are also discussed in this paper.

Preparation and Consideration of Sample Collection in Undeclared Areas for Denuclearization Verification

  • Kim, Dong Yeong;Kim, Giyoon;Lee, Jun;Lim, Kyung Taek;Chung, Heejun;Seo, Jihye;Kim, Myungsoo
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
    • /
    • v.19 no.4
    • /
    • pp.479-489
    • /
    • 2021
  • The Republic of Korea is expected to participate in the denuclearization verification activities by the International Atomic Energy Agency (IAEA) in case any neighboring countries declared denuclearization. In this study, samples for the verification of nuclear activities in undeclared areas were selected for the denuclearization of neighboring countries, and the appropriateness of the procedures was considered. If a country with nuclear weapons declares denuclearization, it must be accompanied by the IAEA's verification regarding nuclear materials and weapons in the declared and undeclared areas. The analysis of the process samples or on-site environmental samples and the verification of undeclared nuclear facilities and materials aid in uncovering any evidence of concealment of nuclear activity in undeclared areas. Therefore, a methodology was established for effective sampling and analysis in accordance with proper procedures. Preparations for sampling in undeclared areas were undertaken for various potential scenarios, such as, the establishment of zones according to radiation dose, methods of supplying electricity, wireless communication networks, targets of sampling according to characteristics of nuclides, manned sampling method, and unmanned sampling method. Through this, procedures were established for pre- and post-site settings in preparation for hazards and limiting factors at nuclear inspection sites.