The Study Of Measurement And Concentration Of The PU In The Marine Eviorment Near The Nuclear Power Plant Of South China Sea

Plutonium is one of transuranic element, with more than 20 isotopes including 238 Pu 239Pu, 240 Pu, 241 Pu and so on. Plutonium is a potential risk for marine organism and human living because of the long half-live and high radiotoxic. Plutonium and its isotopes has a single and reliable source, the unique chemical properties, the different isotopes` ratios from the various sources, so that it is used to distinguish the source of radioactive pollutants in marine environment, to define the space/time condition and to assess the influence from plutonium input/output. It helps to understand the absorption, concentration and transfer of plutonium in the marine environment. It is as a potential tracer to understand the physical and biochemical processes, e.g. the seawater diffusion and mixing, sedimentation and its accumulation rate, etc., and helpful to assess and improve the regional and global ocean model to study the past and the future.In this study, many literatures at home and abroad were firstly investigated and summarized in order to understand the source, distribution, Biogeochemistrical behaviours of Pu isotopes in marine environment, and the potential poxy to trace ocean progress. Secondly, the analyscial method of Pu isotopes in marine environment was consulted and discussed, to establish a fast, efficient, low environmental pollution method based on the facilities in our laboratory. Pu and its isotopes in the seawater, sediment and organisms samples from the coastal areas, especially near the plants, in South China Sea, were measured to study Pu biogeochemical behaviours in marine environment. The papper comprise of these sutaies:(1) The indagate methodology research of PuBase on the principles about the radiochemical separation, anion exchange and flow / sequential injection,a suitable, quick and efficient method was attempt to be established using a microwave digestion—auto-enrichment and purification—detection systems, to study the composition and distribution of plutonium in marine samples, e.g. sea water, sediment and organism. The flow injection/sequential injection(FI) /(SI) technique was firstly introduced into Pu purification and separation process, and a semi-automated was established to separate Pu isotopes from matrix and some interferes in marine samples at home.(2) Pu isotopes in the South China Sea were investigated firstlySome samples were collected at the sea areas near nuclear power plants,e.g. Daya Bay nuclear power plants(DNPP), Fangchenggang nuclear power plant(FCNPP) and Changjiang nuclear power plant(CJNPP), in South China Sea. Pu isotopes and other nuclides(137Cs, 90 Sr and U) in seawater, sediments and marine organisms were firstly measured to understand the source, distribution.Based on the datas obtained, it was shown that 239+240Pu concentrations in sea water near NPP, in South China Sea ranged from 0.0094 to 0.3150 mBq/L,with the mean value of(0.0645±0.0106)mBq/L. It was at the same level of Pu content in the global ocean from literatures. Based on the 239+240Pu/137 Cs activity ratios, Pu in seawater near the nuclear power plant may have some other sources except for global falls sourcs. The results on Pu in these sea areas also should provide the base data for the future study.