Heteronuclear radioisotope nanoparticle of core-shell structure and preparation method thereof

Abstract

Heteronuclear radioisotope nanoparticle of core-shell structure and a preparation method thereof are provided. The Heteronuclear radioisotope nanoparticle of core-shell structure comprising core of two different radioisotopes selected from a group consisting of 198 Au, 63 Ni, 110m Ag, 64 Cu, 60 Co, 192 Ir and 103 Pd, and a shell comprising Si0 2 surrounding the core. The Heteronuclear radioisotope nanoparticle of core-shell can be used as a tracer for the purpose of detecting variation of volume ratio or for the evaluation of the behavior characteristic of a water resource, based on information about phase ratio in the flow of multiphase fluid existing in a process which is operated under extreme condition such as high temperature and/or high pressure conditions.

What is claimed is: 
     
         1 . A Heteronuclear radioisotope nanoparticle of core-shell structure, comprising a core comprising two different radioisotopes selected from a group consisting of  198 Au,  63 Ni,  110m Ag,  64 Cu,  60 Co,  192 Ir and  103 Pd, and a shell comprising SiO 2  surrounding the core. 
     
     
         2 . The heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 1 , wherein the core comprise a combination of  198 Au and one of the rest of the group except  198 Au. 
     
     
         3 . The heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 1 , wherein the two different radioisotepes of the core emit radiations distinguished from each other. 
     
     
         4 . A method for preparing the heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 1 , the method comprising:
 (step 1) preparing cores of the heteronuclear nanoparticle by dispersing two different types of atoms selected from a group consisting of Au, Ni, Ag, Cu, Co, Ir and Pd in water, and stabilizing the result with colloid stabilizer;   (step 2) preparing nanoparticle with core-shell structure by coating the nanoparticle core prepared at step 1 with SiO 2  repeatedly for several times;   (step 3) removing the colloid stabilizer remaining in the core-shell structure prepared at step 2 by calcining the prepared nanoparticle; and   (step 4) activating the nanoparticle within the core by irradiating neutron onto the nanoparticle with the core-shell structure prepared at step 3.   
     
     
         5 . The method as set forth in  claim 4 , comprising applying the colloid stabilizer to the nanoparticle by irradiating radiation to stabilize the nanoparticle core of step 1. 
     
     
         6 . The method as set forth in  claim 4 , wherein the colloid stabilizer of step 1 is polyvinylpyrrolidone. 
     
     
         7 . The method as set forth in  claim 4 , wherein the calcining for removing the colloid stabilizer in step 3 is performed under nitrogen flow at 500-600° C. 
     
     
         8 . The heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 1 , which is used as a tracer for the purpose of detecting movement of multi phase fluid existing in a process operated under extreme condition including high temperature and/or high pressure, or for the purpose of evaluating behavior of water resource. 
     
     
         9 . The heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 8 , wherein ratios of respective phases are measured through flow detection on the multi phase fluid, and information regarding volume ratio of the multi phase fluid is obtained therefrom. 
     
     
         10 . The heteronuclear radioisotope nanoparticle of core-shell structure as set forth in  claim 8 , wherein the fluid existing in the process is dual phase fluid.