[en] In this experiment, rare earth elements are separated from uranium by using the alumina column, anion exchange resin column, and 20% TOA in xylene and fluorescence characteristics were found in the solid matrix to analyze these elements without preseparation from each other. It becomes clear that the YVO₄ matrix is more sensitive than the Y₂O₃ matrix when the red filter is used to minimized the second order peak intensity. And micro quantity of the rare earth elements in the yellow cake are analyzed by the using of the YVO₄ soid matrix. (Author)

[en] Most of all elements in the river such as Be, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Hg, Si, V, U, Cl^-, DO, F^- NO₃^-, PO₄^3-, SO₄^2-NH₃ including pH, water and air temperature, grease oil, hardness and residue, are analyzed on water sample. Atomic absorption spectrometry is used for analysis of a trace amount of metals and specrofluorimetry is applied for the uranium analysis in the water. (Author)

[en] Fluorimetric method in fused solid fluoride flux is used for the analysis of microquantity of uranium, less than ppm order. A rotary propane gas buner as a flux fusion apparatus has been designed and made in order to minimize the deviation occured when electric muffle furnace being used. The standard deviation (6) is 2.9 per cent with a pure sample of 0.1μg U₃O₈/flux while about 10 per cent with samples contained various impurities and its detection limit is down to 10^-5μg U₃O₈/flux. The potentiometric titration method for halides, ion selective electrode method for fluoride, and nitrate, uranium saturation method for TBP and methyl orange colorimetric method for alamine 336 are applied, and gravimetric by phosphomolybdate is used for the phosphate. In addiation, multichannel analyzer has been used to analyze an individual nuclide from its mixture witout/ chemical separation by the determination of γ-ray energy and radioactivity. (Author)

[en] Spectrofluorimetry with benzoin and spectrophotometry with methylene blue have been tried to develop a routine analytical method of determining trace amount of boron in nuclear and cladding materials. Both methods may be utilized for the boron micro-analysis although many technical difficulties are still expected. A satisfactory procedure by a pyrohydrolysis technique is established and applicable to the determination of fluoride in nuclear materials with ion selective electrode after separation from the uranium matrix. Beryllium in the Be-coating laboratory has been monthly monitored and its contamination stays well below the maximum permissible concentration. A preliminary survey on the possible recovery of NH₄NO₃ from the liquid waste of the uranium conversion process reveals that it is more practical to recover NH₃ and NO₃ independently rather than to treat the liquid waste directly to obtain in the form of NH₄NO₃. Several methods should be combined to solve the problem more efficiently. Finally, safeguards activities are summarized

[en] Spectrophotometric methods were extensively employed for the determination of uranium in a variety of ores containing low uranium contents. The effects of matrices was evaluated by treating the data statistically. The mixed acid, HNO₃ and HClO₄ was favourable to the treatment of ores. The method using Arsenazo III as the metallochromic reagent showed higher sensitivity and more precise and accurate results than other spectrophotometric methods in this investigation. Some fluorometric techniques were investigated for determining micro amount of uranium in several fluxes. The extrapolation and standard addition method were directly applicable to simple aqueous solutions, using a carbonate flux whose fusion temperature was lower than a fluoride flux. The impure samples including various interfering elements were purified by the solvent extraction. Th, and other metallic impurities in the uranium samples were quantitatively analyzed by various methods. For the spectrophotometric determination of thorium, the interfering cations were quantitatively separated by adsorption on a column of the cation resin, Dowex 50 X8

[en] The distribution of ³⁵S amongst different chemical species, following production by ³⁵Cl(n,p)³⁵S, in CN^-, SH^- and S^2- doped samples of potassium chloride has been investigated. Evidence is presented showing that the sulphite and sulphate precursors are formed by the reaction of sulphur with V type centres. Part at least of the sulphur is immobile at room temperature. Some unusual effects are observed on annealing the SH^- doped samples. (author)

[en] The safe disposal of radioactive waste has been a matter of national concern. The disposal methods, such as an intermediate depth disposal of low- and intermediate-level radioactive waste and a deep underground disposal of high-level radioactive waste, are being studied in depth. In a geologic nuclear waste repository, the radioactive waste will be isolated from the biosphere by several barriers. Assurance on the long-term safety of the disposal system becomes the basic regulatory requirement for a geologic repository. Reliable predictions of long-term performance can be based on simple but conservative theoretical models, if the assumed parameters are reliably known. The groundwater will have a direct contact with the waste form only after the waste container fails. In this paper the authors analyze container failures and radionuclide transport through penetrations in steel container. They assume that penetrations result from corrosion

[en] Distribution coefficients of some rare earth elements, Sm, Eu, Gd and Dy, between cation exchange resin and hydroxyisobulyric acid were determined. Sm, Eu, Gd and Dy in magnesium diuranate samples were separated chromatographically and found to be existing by on amount of 0.36, 0.18, 0.73 and 0.40ug/g of sample by fluorimetry. An apparatus and procedure for electroplating actinide elements was made and established. Percentage recoveries of the electrodeposition were 98.3% with +-0.7% reproducibility. By this method and alpha spectrometry, we obtained the atom ratio of U-238 and U-234 for a natural uranium sample of Korean originality (Kwe-San, Choong-Buk) as 1:6.1x10sup(-5). For a neutron-irradiated uranium sample electrodeposition and alpha spectrometry resulted in 2.39g/1, 0.620mg/1 and 1.24ug/1 for the concentration of U-238, Pu-239 and Am-241, respectively. Gamma ray emitters in the irradiated sample were determined by gamma spectrometry. After Pu and Np in the sample were separated by anion exchange chromatography and by TTA extraction each followed by alpha spectrometry, it was found that Pu-239 concentrations were 0.60 and 0.55mg/1 by each method. Isotope dilution analysis accompanied by ion exchange chromatography and mass spectrometry of the irradiated sample in purpose of U, Pu and Nd determination reveable U-238 concentration to be 2.48g/1. (Author)

[en] Being short of natural resources, the Republic of Korea depends relatively large portion of its power generation upon nuclear energy. For the continuous utilization of nuclear energy, the public should be convinced that the necessary technologies and wherewithals are already available for the guarantee of the safe management of radwastes. The status and national policy of the radwaste management in Korea including R and D activities are covered herein. The outgoing activities of the Korea Advanced Energy Research Institute (KAERI) in the field of radwaste management include the areas of handling, treatment, storage and disposal of various radwastes, safety assessment of radwaste disposal, and the decontamination and decommissioning of nuclear facilities. In compliance with the national radwaste management program, a centralized repository is expected to be operable by the early 1990's in the Republic

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