摘要: |
用大亚湾近岸沉积物进行人工放射性核素的吸附研究。测得各放射性核素的吸附分配系数(Kd)分别为:85Sr,160;134Cs,330;60Co,6400;141Ce,9500;59Fe,9400;54Mn,15000。并测得核素吸附分配系数随悬浮物浓度(Cp)和示踪剂活度(A)变化的规律。当悬浮物浓度(Cp)增加时,85Sr和59Fe的Kd值显著降低,141Ce,54Mn和60Co的Kd值稍有降低,而134Cs的Kd值几乎不变。当核素示踪浓度增加时,141Ce和59Fe的Kd值随着增大,而60Co,85Sr和134Cs的Kd值稍有降低。 |
关键词: 大亚湾 沉积物 人工放射性核素 吸附 |
DOI: |
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基金项目:国家自然科学基金资助,3870365号 |
附件 |
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ADSORPTION OF RADIONUCLIDES BY THE PARTICULATE MATTER FROM THE SURFACE SEDIMENT OF DAYA BAY |
Wang Jianlin, Lin Zhiqing, Zheng Jianlu
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South China Sea Institute of Oceanography, Academia Sinica, Cuangzhou 510301
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Abstract: |
Adsorption of six radiotracers , 85Sr, 134Cs, 141Ce, 59Fe, 60Co and 54Mn by the particulate matter from the surface sediment of Daya Bay was studied in laboratory experiments from the magnitude and change of adsorption distribution coefficients (Kd) of these radiotracers as functions of equilibration time, suspended particle concentration and radiotracer activity, this work has given an important insight into the possible behaviors of these radionuclides and their radioisotopes in the seawater/suspended particle system of Daya Bay.
In this study, the adsorption distribution coefficients of these tracers were determined as follows: 85Sr, 160; 134Cs, 330; 60Co,6 400; 141Ce, 9 500; 59Fe, 9400 and 54Mn, 1500. Kd for most employed radiotracers increased with equilibration time and reached constant value within one day (except 60Co). For 60Co, its Kd reached constant in about three days. As a function of suspended particle concentration (Cp), Kd for 85Sr and 59Fe obviously decreased with increasing Cp, and Kd for 141Ce, 54Mn and 60Co decreased slightly while Kd for 134Cs was nearly constant with increasing Cp. As a function of tracer activity, Kd for 141Ce and 59Fe increased with increasing tracer activity, but Kd for 54Mn, 60Co, 85Sr and 134Cs decreased slightly with increasing tracer activity. |
Key words: Daya Bay, Sediment, Radionuclide, Adsorption |