| Environmental pollution has become the global hotspot problem. To study the dynamic behavior of contaminations and to explore new technique for cleanup pollutions are important to resolve this problem.95Zr is one of the fission products and main radioactivity liquid drainages of nuclear reactor. It needs to have a systematic research on the behavior in ecosystem considering the sudden occurring and the serious of harm of the nuclear polluting accident. The leaching and transferring of 95Zr in different soils and its actions in several aquatic and terraneous ecosystems were studied by using the isotope tracer techniques. This would provide some basic data for illustrating the behavior of 95Zr in different agricultural ecosystems and serve as science according for establishing some safety standard and managing pollution.At one time, environmental pollution arising by poisonous pollutes has been global hotspot problem. Because there are no enough efficiency methods to dispose pollute, so to study and develop new methods is very urgent. We do some work to study on the radioresistance bacteria Deinococcus radiodurans to construct one super bacteria, which could resolve the pollution in a complex environment contaminated by both radiation and organic compound.1 The leaching characteristics and vertical transport of 95Zr in two representational soils (panfan red soil and red-yellow earth) in Zhejiang province were studied with soil-pole simulation installation. The results showed that: (1) the content of Zr in collective water was very low and went near to 0. Meanwhile with increasing the total amount of leaching water (250mL~750mL), the gross of 5Zr in leaching water changed indistinctively, which indicated that once 95Zr was absorbed by soils, it was very difficult to unbind by water. (2) most of 5Zr remained in the upper layer soils. In Panfan red soil and red-yellow earth, 90.05%~97.47%, 96.02%~97.16% of the 95Zr concentration were in the upper 0~0.4cmsoils layer respectively, which indicated that both soils had relatively strong adsorption. The results of comparing their change trends clarifed the capability of red-yellow earth absorption was slightly better than that of Panfan red soil.2 The leaching and vertical transport of 95Zr in three representational soils (paddy soil, red-yellow earth and sea mud) in Zhejiang province and the influence of salinity on the activities of 5Zr in sea mud were studied with soil-pole installation. The results showed that: (1) the content of 95Zr in collected leachate was low after passing through soil column with 250mL, 500mL, and 750mL leaching amount. The amounts of 95Zr in collected leachate of paddy soil, sea mud and red-yellow earth were about 5.33%~7.68%, 0.77%~1.32% and almost 0 of labelled amount respectively. And with increasing the total amount of leaching water, the content of 95Zr in collected leachate varied indistinctively, which indicated that once 95Zr was absorbed by soils, it was very difficult to desorb. (2) in paddy soil, red-yellow earth and sea mud, 45.99%~50.02%, 96.02%~97.16% and 95.94%~98.01% radioactivity of 95Zr were concentrated in the 0.4cm upper layer soils respectively, which illustrated that most of 95Zr remained in the surface soils; (3)With the increase of salinity in leaching water, the amount of 95Zr in surface soils (0~0.2cm) presented obviously increased, which demonstrated that increasing salinity could raise the adsorption rate of 95Zr in soils.3 The distributive dynamics of 95Zr absorbed in crucian and the behavioral trait of 95Zr in an aquatic ecosystem was studied by using isotope-tracer technology, and the mathematical model was confirmed by application of nonlinear regression method. The results showed: (1) the activity concentration of 95Zr in water reduced quickly for subsidence, soil absorption, crucian intake, hornwort's absorption and adsorption. The dynamics of its disappearance accorded with binomial index regression law: Cw.=43.36e-1.74t'+12.85e-0.15 (2) the hornwort had stro...
|
PDF Full Text Request