CAJ | 학술논문

锆基烧绿石An2 Zr2 O7以优异的抗辐照性能和化学稳定性成为高放废物中锕系核素的理想固化基材，高放废物固化体在长期贮存过程中不断衰变产生衰变子体，必将影响固化体的结构和性能。本文以镧系核素 Nd 模拟锕系核素 Pu、Am ，La 模拟其衰变子体 U、Np ，通过溶胶凝胶方法合成了（Lax Nd1－ x ）2 Zr2 O7模拟固化体。样品经高能γ辐照，辐照剂量为233.78 kGy。利用 X 射线衍射、Raman振动光谱和结构精修方法对辐照前后的系列样品进行了分析。结果表明：（Lax Nd1－ x ）2 Zr2 O7系列固化体均为单一的烧绿石结构相；固化体的晶格常数随La的增加呈线性增加，晶体结构趋于有序化，意味着衰变子体有助于固化体趋向于更加有序的烧绿石结构。γ辐照和结构精修结果表明，随着子体的增加，An—O48f键长增大，离子键结合力减小，在辐照情况下晶格易发生无序化，抗辐照能力减弱。
고기소록석An2 Zr2 O7이우이적항복조성능화화학은정성성위고방폐물중아계핵소적이상고화기재，고방폐물고화체재장기저존과정중불단쇠변산생쇠변자체，필장영향고화체적결구화성능。본문이란계핵소 Nd 모의아계핵소 Pu、Am ，La 모의기쇠변자체 U、Np ，통과용효응효방법합성료（Lax Nd1－ x ）2 Zr2 O7모의고화체。양품경고능γ복조，복조제량위233.78 kGy。이용 X 사선연사、Raman진동광보화결구정수방법대복조전후적계렬양품진행료분석。결과표명：（Lax Nd1－ x ）2 Zr2 O7계렬고화체균위단일적소록석결구상；고화체적정격상수수La적증가정선성증가，정체결구추우유서화，의미착쇠변자체유조우고화체추향우경가유서적소록석결구。γ복조화결구정수결과표명，수착자체적증가，An—O48f건장증대，리자건결합력감소，재복조정황하정격역발생무서화，항복조능력감약。
T he zirconate pyrochlore is regarded as candidate crystalline matrix to immo‐bilize actinide elements because of its chemistry and radiation stability . T he decay‐daughters from α‐decay of the incorporated actinides can affect the immobilization struc‐ture and properties .Due to similarities in charge ,size and chemical properties ,Nd and La were used as surrogated elements for parent elements (Pu and Am ) and daughter elements (U and Np) ,respectively .The zirconate pyrochlores (LaxNd1 - x)2Zr2O7 were prepared by the sol‐gel method .These samples were irradiated by 60Co γ‐ray source with 233.78 kGy dose .The X‐ray diffraction ,Raman spectroscopy and structure refine‐ment were employed to investigate the structure evolution . The results show that pyrochlores in the (LaxNd1 - x)2Zr2O7 system are single pyrochlore structure .The lattice parameters increase gradually and the degree order of pyrochlore structure increases with the La content . The analysis of the irradiation experiment suggests that the An—O48f bond length increases with the decay‐daughters content ,and the irradiation re‐sistance of pyrochlore immobilization decreases .