Yatsuka Matsuda

Activation Analysis of Polluted River Water

Ge (Li) 検出器によるγ線スペクトロメトリーと電子計算機によるスペクトル解析法を利用する機器測定的放射化分析法をある鉱山の廃水が流入する川の水に適用し, 31種の元素の濃度を決定することができた。そのなかにはCd, As, Sn, Crなどの重要な環境汚染元素も含まれており, 本分析法が鉱山廃水などによる河川水の汚染の分析に有効であることが確かめられた。しかし, ケイ光X線分析で検出されたMoおよびSrを本放射化分析法では定量することができなかった。

PIXE analysis on desorption of elements from coastal sediments

Abstract Coastal sedimental elements were desorbed with ultrapure water, artificial seawater, 0.2M (NH4)2C2O4, 1M CH3COONH4, 0.01M EDTA·2Na, 1N HC1 and 6N HC1, independently. 56 μ1 of extracted fluid was dropped on Kimfoil to make a target. Beam bombardment was done by a cyclotron using a 4.5 MeV proton energy. For a typical sample, the maximum Fe seen in the samples was obtained by extraction with 6N HC1 (7.6 mg/g). In comparison, the Fe observed after extraction with ultrapure water, artificial seawater, and 1M ammonium acetate were essentially zero. However, the amounts seen with 0.01M EDTA·2Na and 0.2M ammonium oxalate were high as 18% and 9.5% of the 6N HC1 value, respectively. About the extraction with EDTA having most excellent characteristics of chelate agent, alkali earth elements, Mg2+ and Ca2+ were detected in almost all samples because they form ionic bonding chelates. Desorption rates of transition metal elements which form coordinate bonding cheates were observed to be proportional to the stability constant except for Mn2+ and Cu2+ anomalies.

Simultaneous Analyses of Gaseous and Particulate Sulfur in the Atmosphere by X-ray Fluorescence Spectrometry

前報に続き, 観測結果を考察した。気体状硫黄濃度の頻度分布は, 海陸風の交替を反映して二山型であった。他方, 粒子状硫黄濃度の頻度分布も二山型であったが, これはむしろ天気の変化を反映していると推測された。気体状硫黄濃度と粒子状硫黄濃度との間の相関は期待していたほど大きくはなかった。気体状および粒子状硫黄濃度の自己相関を調べたところ, 気体状硫黄濃度の変動には日周期が現れていたが, 粒子状硫黄濃度の変動には日周期は見出されず, むしろ天気の変化の影響が現れていた。観測方法の能率化および大気中の硫黄の動態を探るための観測地点の選定法などに関する検討を行った。

PIXE analysis of the desorption of elements from bog mud

Abstract To obtain background information to formulate a strategy to keep lakes, marshes and bogs free from pollution, soil and peat were sampled and analyzed. Sample preparation, size segregation and chemical extraction with ultra-pure water, 0.2M (NH4)2C2O4, 1M CH3COONH4, 0.01M EDTA · 2Na, 1N HCl and 6N HCl were undertaken prior to the normal PIXE target preparation. It was found that the extraction rates of metal elements by oxalate ion decrease with increasing complex formation by the interaction of the metal ions with humic compounds. The extraction rate of Mn by ammonium oxalate solution is low, in spite of relatively low complex formation with humic compounds, presumably because the water-insoluble inorganic colloid (MnO2) is readily formed. The values of the extraction rate nearly correspond to the chelate-formation constants of the metal ions with EDTA. P and S were both effectively extracted by ammonium acetate.

PIXE analysis of Co and Fe in the serum and bone marrow of mice having acquired radio-resistance after small-dose pre-irradiation: Preliminary experiment

Abstract The death of animals occurring due to exposure to less than 10 Gy of ionizing is called bone marrow death. Radiation destroys blood-forming tissues such as bone marrow that produce blood cells. Mice acquire radio-resistance after a small dose pre-irradiation. We tried to obtain some information on the mechanism of the radio-adaptive survival response by measuring Co and other elements in bone marrow and serum of irradiated mice by PIXE. Fe increased after irradiation with 5.0 Gy in bone marrow. But the Co/Fe ratio on day 11 in bone marrow and the ratio on days 10 and 15 in serum after the irradiation was not affected by the pre-irradiation (0.5 Gy).

Behavior of radionuclies during the combustion of liquid scinti-cocktail waste in an incinerator.

排気冷却捕集装置を備えた焼却炉を用い有機廃液中に含有する核種および安定同位元素の焼却による挙動を調べた。この結果PおよびCaは排気中では粒子状, 排水中ではPは粒子状, Caは溶存状がそれぞれ支配的であった。Pの約40%は炉内壁に残存した。排気中で主にガス状で存在するSおよびCについては1NCsOH水溶液によりそれぞれ89%および46%の捕集効率が, またアンモニア水によりSでは95%, Cでは91%の捕集効率が得られた。