Development of the on-line separation and detection system in photon and charged particle activation analysis for high-sensitive detemination of light elements

1998 Fiscal Year Final Research Report Summary

• Project/Area Number: 09640712
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: 分離・精製・検出法
• Research Institution: HIGH ENERGY ACCELERATOR RESEARCH ORGANIZATION
• Principal Investigator: MASUMOTO Kazuyoshi Radiation Science Center, High Energy Accelerator Research Organization, Associate Proffessor, 放射線科学センター, 助教授 (60124624)
• Project Period (FY): 1997 – 1998
• Keywords: activation analysis / materal analysis / light elements analysis / slectron linear accelerator / photon activation analysis / cyclotron / charged particle activation analysis / flow injection

Research Abstract

According as the recent industrial demands for the high-pure materials, it is necessary to develop highly sensitive analytical methods. Since the establishment of the world trading organization (WTO) in 1995, the guarantee of tractability based on precise and accurate analytical methods and analytical standards has become indispensable in each member nation. It has been recognized that activation analysis using an electron linear accelerator and a cyclotron is one of the most prominent method for the determination of trace amount of light elements in high-pure materials. A rapid separation and detection of short lived radioisotopes from light elements is necessary for activation analysis of light elements. In this work, a sequential method has been developed as follows. (1) A bombarded sample is oxidized in a gold image infrared furnace under oxygen stream. (2) A radioactive carbon dioxide is extracted into mono ethanol amine solution in a coiled glass tube. (3) Radioactivity in ethano iamine is continuously monitored with a pair of BGO scintillation detector coupled onto a coincidence circuit. Photon activation analysis of carbon in steel standards has been performed at the Laboratory of Nuclear Science, Tohoku University. Carbon can be determined by detecting ィイD111ィエD1C from the ィイD112ィエD1C(γ,n)ィイD111ィエD1C reaction. A sample was irradiated with bremsstrahlung (Emax=30MeV) for 20 min. The oxidation condition such as temperature, time, and amount of accelerator, and the extraction condition of ィイD111ィエD1COィイD22ィエD2 such as concentration of ethanol amine, and flow rate of oxygen, have been checked. A good linear relationship between obtained integral counts and amount of carbon was attained by this system. The detection limit was less than 1 μg/g for the case of steel standard. Charged-particle activation analysis of nitrogen in silicon crystal has been also performed at the Center for Nuclear Study, Tokyo University. Nitrogen was determined by detecting ィイD111ィエD1C from the ィイD114ィエD1N(p,α)ィイD111ィエD1C reaction. Sample was bombarded with proton of 13- MeV, 1μA for 20 min. First, a sample irradiation system was set up on the Rl-production channel. After bombardment, the same separation and detection system as PAA was used for nitrogen determination. It was found that the traditional calibration coefficient for nitrogen analysis using FT-IR method can apply to FZ : silicon but not to CZ silicon. This flow method is hopeful for the light element analysis because of its simplicity and