In-air microparticle induced X-ray emission analysis of particles in interstitial pneumonia lung tissue obtained by transbronchial biopsy

Interstitial pneumonia develops in association with inhaled particles. In-air microparticle induced X-ray emission (in-air micro) analysis was previously employed to assess the spatial distribution and content of particles in surgical lung biopsy specimens. The aim of this study was to assess the efficacy of in-air micro-analysis for transbronchial lung biopsy specimens in patients with or without occupational exposure. The elements composing lung particles and their locations could be identified by in-air micro-analysis. Silicon was the major component of particles. Quantitative analysis revealed that the elements composing lung particles varied between patients. In a patient with suspected nickel exposure, aluminium, vanadium, and calcium were detected, but was not detected. In a patient without a work history (housewife), various elements were detected. In-air micro-analysis was useful for assessing the spatial distribution and content of particles in specimens from patients. Occupational exposure was not necessarily associated with deposition of particles in the lungs. Therefore, in the diagnosis of, elemental analysis of specimens by in-air micro-analysis could be useful for assessing exposure to particles objectively

Evaluation of the Cooling Effect by He Gas for the Production of At-211 with a Bi plate

Astatine-211 is one of the promising alpha-emitting radionuclides for the targeted alpha therapy (TAT), internal radiotherapy using alpha-emitting radioisotopes. At-211 is basically produced by irradiating He beams with 28–29 MeV to a bismuth (Bi) target. Irradiations with high beam current (µA order) are necessary to produce At-211 for preclinical and clinical studies because they require its radioactivity on the order of subGBq to GBq. Low melting point of Bi (273.1°C) often causes melting of the Bi during irradiation with high beam current. The aim of this study is therefore to optimize irradiation condition without observing Bi melting

Microscopic analyses of complexes formed in adsorbent for Mo and Zr separation chromatography

高レベル放射性廃液(HALW)の処理に於いて、抽出クロマトグラフィーによる高効率なマイナーアクチノイド(MA)の回収にはモリブデン(Mo)及びジルコニウム(Zr)の事前除去が必要である。そこで、MoとZrの除去と回収を目的としてbis(2-ethylhexyl) hydrogen phosphate (HDEHP)を含浸させた吸着材を用いることを考案し、模擬HALWのカラム分離実験で、MoとZrを選択的に吸着させて除去することに成功した。次に、吸着材からそれらを回収するための溶離液として過酸化水素水を用いたところ、Moのみ溶離された。この吸着材のマイクロPIXE、EXAFS及びX線小角散乱法による分析結果は、結晶状のZr-HDEHP複合体が吸着材中に一様に形成されたことを示していたことから、Moは今回の方法で除去・回収できるが、Zrは結合が強く、過酸化水素水では回収できないことがわかった

Observation of changes in ion beam induced luminescence spectra from organics during focused microbeam irradiation

数100μｍ径のエアロゾル等に付着した化学物質の同定とマイクロメートルレベルの分解能での分布の計測を可能にすることを目的に、イオンマイクロビームの物質照射によるIBIL (ion beam induced luminescence: イオンビーム誘起発光)をフォトンカウンティングレベルの高感度で多波長同時計測と2次元マッピングを実現する技術として、高効率光学格子と32チャンネルアレイの光電子増倍管を用いた高感度波長分散IBIL分析システムを開発した。3MeVのプロトンマイクロビームを標準試料（有機化合物）に照射して発生した可視光を用いてシステムの性能評価を行った結果、有機化合物の分析に十分な波長分解能と、多波長の発光強度を同時に10μmより高い空間分解能でマッピングでき、目標性能を達成した