[en] Half-life of krypton-88 is 2.84 hours, high fission yields and a relatively large gamma branching ratio is had. The gas is short-lived fission products in burnup measurements. Only New fission products can extract from extraction in gas of fissile irradiation target. But krypton-88 with krypton-85, krypton-87, xenon -135, and xenon-138 is coexisted together, thus radiochemical separation must quickly taken. selected the irradiation time is 1-2 hours and cooling time is best 2 hours for sample preparation, krypton and xenon were separated using activated carbon adsorption, the ratio of krypton and xenon were measured by gamma spectroscopy. Then according to the ratio of krypton-85 and xenon-125 count rate coefficient around separation were calculated yield of krypton and decontamination factor of xenon and the final the yield of krypton-85 is calculated. (authors)

[en] It is difficult to determine the concentration of a-emitting nuclides of raffinate and detergent in process feed solutions due to its low concentration. The conventional radiochemical analysis methods cannot meet the new demand. A novel analytic technique using scintillating glass to determine the concentration of a-emitting nuclides in liquid was present in this paper. The glasses and detection system were build and its performance index met the requirements and achieved the expected effect. (authors)

[en] In order to achieve continuous monitoring of ⁹⁰Sr in aqueous solution, ⁹⁰Sr was firstly separated selectively and enriched by SuperLig®620 solid phase extraction beads, which was then measured in-situ using plastic scintillator. The influences of ⁹⁰Sr activity on two-phase equilibrium were studied and the results show that the concentration in aqueous solution is directly proportional to that captured on the column in 0.2 mg/L Sr-0.01 mol/L HNO₃ medium. So the concentration of ⁹⁰Sr in aqueous solution can be analyzed by detecting ⁹⁰Sr on the column. The detection efficiency and minimum detectable activity are 21.3% and 2.6 Bq/L, respectively. The concentration of ⁹⁰Sr in low level radioactive waste water was analyzed using the above method and the analytical error is lower than 20%. (authors)

[en] A sequential separation method of U, Np and Pu from rock samples was established in this work. After digest the samples, Fe(OH)₃ coprecipitation and TBP extraction chromatography were used to remove the matrix elements and extracted U, Np and Pu. The U, Np and Pu fraction was separated by high performance liquid chromatography on a C18 reversed-phase column. A small amount of ²³⁷Np and ²³⁹Pu tracer was added to the non-radioactive rock samples, and dealt with the process, the chemical yield of Np and Pu were both better than 90%. The Uranium content of the sample was measured by MC-ICP-MS. the results are accordance with the ones determined by neutron activation method. (authors)

[en] In order to get the decay data of ⁹⁰Rb measured more accurately, a sample of ⁹⁰Rb of radiochemical purity has to be prepared. A separation method was established based on twice delay separation method, in which the high isotope abundance can be extracted from new produced fission product. First of all, the gaseous fission product ⁹⁰Kr was extracted from the irradiated target by a deflation procedure, and then through a washing procedure, the ⁹⁰Rb generated by ⁹⁰Kr decay was collected. A system for rapid extracting ⁹⁰Kr was also developed. Finally, a carrier-free ⁹⁰Rb product of high specific activity was obtained. The total recovery of ⁹⁰Rb is about 20%. The decontamination factor of the main impurities is about 10³. The whole procedure costs in 2.5 min. (authors)

[en] In order to prepare ⁸⁸Kr samples for the corresponding nuclear data measurement, a method for radiochemical separation of ⁸⁸Kr has been investigated by activated carbon adsorption in this work. The absorption conditions of activated carbon column were studied by using ⁸⁵Kr and ¹²⁵Xe as the radioactive gas tracers. The results show that Xe can be absorbed quickly on the activated carbon column at low temperature (0 ℃), whereas Kr shows no such property. ⁸⁸Kr samples are easily enriched from the irradiated uranium targets by utilizing the separation system which is designed for the short-lived gaseous fission products. The recovery yield of Kr is better than 90% and the decontamination factors for Xe and I are more than 1 × 10⁴. The whole procedure can be completed in less than 5 min. (authors)

[en] ²⁴¹Am in many soil samples should be analyzed, so that radioactive pollution level in nuclear facilities and its affinity environment can be surveyed efficiently. In this paper, in order to input the optimal conditions for column experiment, firstly, the experiments of adsorption coefficient of ²⁴¹Am to DGA resin under different contact time, concentration of HNO₃ and different temperature were carried out. The chemical procedure for the rapid separation and determination of ²⁴¹Am in soils was formulated, which used DGA resin as extraction material and liquid scintillation spectrometry counting as measurement, EDTA solution as desorption mean. When the soil sample mass is 10 g, leached by 8 mol/L HNO₃, the chemical recovery of the procedure is about 95%, and the minimum detectable specific activity is 3.1 Bq/kg. Typically, a sample can be analyzed in 3 h. The presence of ¹³⁷Cs, ⁹⁰Sr-⁹⁰Y, ²³⁹Pu, ⁹⁹Tc doesn't interfere with the procedure, owning high DF of them. The procedure can be used extensively. (authors)

[en] In order to measure the radioactivity of pure beta-emitters, which are low energy, low level and lack of their standard solutions, an efficiency calibration method was developed by scaling the liquid scintillation spectrometer (LSA) with 6 low energy beta-nuclides. On the base of this method, a three-dimension surface on nuclides' average energy, quenching index and determining efficiency was fitted. Various factors possibly influencing the measurement of LSA were studied, such as scintillation fluids, quenched agents, medium, vials, volumes and so on, and the optimum conditions for LSA were obtained. (authors)

[en] To determine the half-life of gaseous fission product ⁸⁸Kr accurately, three purified ⁸⁸Kr sources were prepared from irradiated uranium targets by using a radiochemical separation process. With ⁸⁵Kr as the internal monitor, ¹³⁷Cs/⁵⁷Co as the external label sources, both single detector position relay method and double detectors position relay method were applied to track the characteristic 196.3 keV gamma rays by multiple high purity germanium detectors covering more than eight times half-lives. The results from three separate determinations were discussed, and a half-life of (2.796 ± 0.015) h for ⁸⁸Kr was presented. (authors)

[en] In order to improve the accuracy of the fission yields of ¹⁵⁶Eu and ¹⁶¹Tb in neutron-induced uranium fission, radiochemical purity sample of ¹⁵⁶Eu and ¹⁶¹Tb has to be obtained. A separation procedure of Eu and Tb from uranium, aluminum and fission products was established in this paper. Aluminum was first removed by hydroxide co-precipitation method, then uranium was removed by calcium fluoride co-precipitation method, and rare earth elements were recovered by 30% TRPO-kerosene extraction method, Eu and Tb were separated from the mixed rare earth elements by cation exchange chromatography method. When the sample contains 2 g uranium, 0.65 g aluminum and fission products, the chemical recoveries of Eu and Tb are better than 80%, the decontamination factors are greater than 10⁶ for U, ²³⁹Np, ⁹⁵Zr, ¹⁰³Ru, ¹³¹I, ¹³²Te, ¹⁴⁰Ba, ¹⁴⁰La, ¹⁴¹Ce and ¹⁴⁷Nd. The method can meet the requirement of measurement of ¹⁵⁶Eu and ¹⁶¹Tb yield in neutron-induced uranium fission. (authors)