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氚水在大豆土壤系统中的迁移与分布 总被引:8,自引:2,他引:6
采用模拟污染物的同位素示踪技术研究氚水在大豆-土壤模拟生态系统中的迁移、分布规律.通过为期50d的模拟试验,测定了植物和土壤样品中2种形态氚(自由水氚和结合态氚)的比活度.结果表明:引入土壤中的氚水,不仅在系统各分室间转移和分配,而且迅速向系统外散逸;氚水中的氚以自由水氚和结合态氚形态存在于大豆植株和土壤中;大豆植株中的自由水氚比活度于6h时即达最大值(根19.4Bq·g-1;茎叶12.3Bq·g-1),随后便逐渐下降,而结合态氚呈缓慢增加;大豆根中的总氚比活度开始时高于茎叶中的比活度,而后趋于平衡,表层土中2种形态氚基本呈逐渐下降.运用示踪动力学分室模型原理对实验数据拟合得:土壤中的比活度Cs=88.37e-11.847t+7.38e-0030t;大豆植株中的比活度Cb=10.30(e-0.030t-e-11.847t). 相似文献
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采用模拟污染物的同位素示踪技术研究HTO(氚水)在茶树-土壤模拟生态系统中的迁移规律。测定了植物和土壤样品中两种形态氚(自由水氚和结合态氚)的比活度,并应用具有相互交换的双库室开系统模型确定了茶和土壤分室的拟合方程。结果表明:引入土壤中的HTO,不仅在系统积分室间转移和分配,而且迅速向系统外扩散;HTO中的氚以自由水氚和结合态氚形式存在于茶树中,以吸湿性水氚和结晶水氚存在于土壤,其中自由水氚(或吸湿性不氚)远大于结合态氚(或结晶水氚);对实验数据进行回归分析得;茶树植株中的总氚比活度Ct(t)=314.09(e^-0.0569t-e^-0.3777t),土壤中的总氚比活度Cs(t)=136.73e^-0.3777t 112.22e^-0.0569t。 相似文献
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Kurbatova EI Ksenofontov AI Dmitriyev AM Regens JL 《Environmental science and pollution research international》2007,14(4):251-255
Background, Aims and Scope Advances in radioecology can support improvements in environmental remediation technologies, especially by illuminating interaction
processes between polymorphic metal radionuclides and various materials and their ions in aqueous solutions. This study modeled
interaction processes of 90Sr with transitive metals to delineate the behavior of polymorphic metal radionuclides. Experimental and modeling results
confirmed Sr sedimentation was sensitive to the physical impact of radionuclides on various sorbents and possible chemical
reactions occurring between the radionuclides and sorbents.
Methods Models were developed to simulate 90Sr sedimentation process, and the potential physical and chemical reactions accompanying the process. Models were verified,
inorganic salts were used as sorbents to absorb metal cations, activity levels were recorded before and after mixing the inorganic
salts while the efficiency of sedimentation using the heavy metals composites was quantified.
Results and Discussion This research demonstrates that the process of the sedimentation is complex and occurs in several stages. Micro-structural
analysis shows that zones of interaction between the sorbent and source metal are formed during the irradiation of the target’s
metal surface. Electrical-microscopic analysis indicates that the composition of the formed zones of interaction of Ti (Sr)
with target metals has various structures. Roentgenophase analysis indicates that the interaction of the ions of a precipitable
source and a target occurs according to constitution diagrams of equilibrium systems. The results indicate that application
of inorganic salts composites based on modeling increases the efficiency of the deactivation of aqueous solutions when compared
to standard aluminum sulfate composite.
Conclusions Experimental and modeling results confirm 90Sr sedimentation is sensitive to the physical impact of radionuclides on various sorbents and possible chemical reactions
occurring between the radionuclides and sorbents. The models support estimation of the physical impact of polymorphic metal
radionuclides on various components of sorbents and possible chemical reactions occurring between the radionuclides and sorbents
during the interaction. Inorganic salt composites deactivate and clear 90Sr and Sr+2 from water.
This paper is openly accessible! 相似文献
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D. A. Krivolutskii 《Russian Journal of Ecology》2000,31(4):233-237
Lands that have become unusable because of contamination with long-lived artificial radionuclides require special measures
aimed at their monitoring and rehabilitation. In such areas, specific processes in the biota are associated with the direct
effect of ionizing radiation on some species, secondary changes depending on the ecology of organisms trophically connected
with these species, and side effects explained by the regime of isolation established in radiation reserves. The dynamics
of floras and faunas in radiation reserves are determined by successional changes in plant communities, migration of radionuclides,
and the protective status of these territories. 相似文献
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采用模拟污染物的同位素示踪技术进行了95zr在2种作物-土壤体系中的消长动态研究,并应用库室模型和非线性回归方法确定了各体系的拟合方程.结果显示:①玉米和大豆从土壤中吸收的95Zr主要集中在根部,且根部中的95Zr比活度随时间呈缓慢增加,并在经历一段时间后逐渐趋于动态平衡;其余各部位的比活度较低,较大部分接近于本底水平,表明95Zr被玉米和大豆根系吸收后不易在其体内迁移、输运;②喷施进入土壤中的95Zr主要滞留在表层(0~8cm)土壤中,其量占总量的97.5%以上,表明95Zr被表层土壤吸附,不易随水流向下迁移;③对实验数据进行回归分析,得玉米和大豆植株中95Zr比活度的消长动态拟合方程为Cm(t)=3.2067(1-e01582t)和Cb(t)=3.0925(1-e-0.1363t),经方差分析,表明回归方程较好地反应了95Zr在玉米-土壤和大豆-土壤体系中的消K动态. 相似文献
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