• Transactions of the Korean hydrogen and new energy society
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• v.32 no.4
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• pp.219-227
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• 2021

Hydrogen isotopes, which are used as raw materials in fusion reaction, participate in the reaction only in small amount, and most of them are released together with impurities. In order to recover and reuse only hydrogen isotopes from this exhaust gas, a recovery process is required, and most of the hydrogen isotopes can be recovered using a Pd Membrane. In this study, the recovery rate of hydrogen isotopes was measured through the first and second stage Pd membrane experiments. In the case of the experiment using a single stage Pd membrane, about 99.2%, and in the case of the first stage and second stage Pd membrane connection experiments, a recovery rate of 99.9% or more was obtained. Therefore, the recovery rate of Pd membrane process applied to hydrogen can be applied to hydrogen isotopes. In addition, the simulation model was established using aspen custom modeler, a commercial software, and the validity of the simulation was checked by applying the references and experimental data. The simulation results based on the experimental data showed a difference of 2% or less.

• Journal of Wetlands Research
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• v.13 no.3
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• pp.515-522
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• 2011

This study examined the epiphytes using stable isotopes. Separated epiphytes should represent the water quality. In study areas, where agricultural paddies were prevailing, biomass of epiphytes can increase nitrogen isotopes(${\delta}^{15}N$) and as a result decrease in carbon isotopes(${\delta}^{13}C$). Naerin stream and Inbuk upper areas showed higher nitrogen isotopes(${\delta}^{15}N$) than in Hangye and Buk stream. Also, stable carbon isotopes(${\delta}^{13}C$) in Naerin stream and Inbuk streams tended to increase than in Hangye and Buk stream. This can indicate the epiphytes can be a good indicator for water quality pollution.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2005.05a
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• pp.28-32
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• 2005

본 연구는 Karr column을 이용한 희토류원소의 분리에 대한 기초 연구로서, 수상의 초기 pH와 유기상 중 PC-88A의 비누화도에 따른 Nd, Sm의 분리특성을 파악하였다. 실험결과 pH $0.8{\sim}2.3$ 범위에서 PH가 높아짐에 따라 Nd, Sm의 추출율 및 분리계수가 증가하였으며, PC-88A 비누화도 40%인 조건에서 추출 후 수상의 초기 PH에 관계없이 평형 pH가 약 1.5 정도로 유지되는 것을 알 수 있었다. 그리고 PC-88A 비누화도가 증가함에 따라 Nd, Sm의 추출율이 크게 증가하였으며, 비누화도 40%인 조건에서 가장 높은 분리계수(${\beta}_{Sm,\;Nd}\;=\;10.8$)를 보여 주었다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.6 no.1
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• pp.25-33
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• 2008

A selective separation of Actirlide(III) by a nPr-BTP/nitrobezene extraction system was studied. The nPr-BTP (2.6-Bis-(5.6-n-propyl-1.2.4-triazin-3-yl)-pyridine) of a environmentally -friendly CHN type was self-synthesized and its compatability with diluent and stability with nitric acid were investigated. At the 0.1M nPr-BTP/nitrobenzene-1M $HNO_3$ and O/A=2, extraction yields of Am used as a representative of Actinide(III) and Eu were about 85% and 8%, respectively, and the other RE elements such as Nd, Ce and Y were extracted less than 3% (separation factor of Am and Eu was about 60). Thus, there was no problems in the selective extraction of Actinide(III) from RE. The stripping yield of Am with 0.05M $HNO_3$ at O/A= 1, however, was about 43% and the maximum stripping yield was 65% at O/A=0.3. It is necessary to develop the stripping system including the stripping agent instead of nitric acid solution.

• Journal of the Korean Chemical Society
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• v.45 no.4
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• pp.304-311
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• 2001

A study has been carried out on the extraction chromatographic separation of fission products from spent pressurized water reactor (PWR) fuels for inductively coupled plasma atomic emission spectrometric analysis. Impregnation capacity of tri-n-butyl phosphate (TBP), which is well known as an extractant in the field of uranium separation from various nuclear grade materials, on Amberlite XAD polymeric macroporous support materials was measured. Amberlite XAD-16 of which the surface area is the highest was selected as a support material because its TBP impregnation capacity was the largest in Amberlite XADs. Sorption behaviour of this TBP impregnated resin was investigated for the fission product elements using acidic solutions simulated for dissolver solutions of spent PWR fuels. The parameters affecting the performance of the separation system were optimized. The fission product elements studied excluding Pd and Ru were quantitatively recovered with the precision of less than 3.1%.

• Journal of the Mineralogical Society of Korea
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• v.30 no.4
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• pp.137-147
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• 2017

Sericite is a clay mineral that has a wide applications in the industry, depending on its purity. To maintain sericite's purity as high as possible it is necessary to remove its gangue minerals or control their contents prior to use for high value-added products and applications. In this study, the wet beneficiation of sericite by applying selective grinding and sedimentation techniques, were investigated. The ore mineral was composed mainly of sericite, quartz and calcite. Analysis showed that the content of sericite increased along with the particle size decrease, but the contents of impurity minerals as quartz and calcite were tended to decrease relatively with particle size decrease. The results of liberation tests using an attrition scrubber showed that the increase in residence time and slurry density have increased the generation of fine particles in -325 mesh size range. It was observed, however, that the contents of impurities such as quartz and calcite in such fine particles also increased during prolonged scrubbing. In the dispersed form without breaking, the yield of the recovered concentrate was 15.4 wt% and the $K_2O$ content was 9.84 wt%, after the dispersed slurry was allowed to settle for 20 minutes. On the other hand, the concentrate yield was increased to 23.4 wt% after 10 minute attrition scrubbing and 40 minute sedimentation, while its $K_2O$ content was decreased to 9.71 wt%. Most of final products were observed as platelet-shaped particles containing Si, Al and K which are main component of sericite.

• Analytical Science and Technology
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• v.13 no.3
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• pp.309-314
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• 2000

The quantitative analysis of various trace metals including fission products in lithium molten salts has been performed using a inductively coupled plasma atomic emission spectrometer (ICP-AES). The spectral interferences of lithium content, 500, 1,000 and 2,000 mg/L, in the sample solution were investigated using an optimum wavelength for the respective metal species. As a result, the line intensities for Y, Nd, Sr, and La had no influences from the lithium content up to 2,000 mg/L, while Mo, Ba, Ru, Pd, Rh, Zr and Ce showed spectral interferences of 10% to 50%. The group separation of metals from lithium in the molten salts solution was carried out by adding ammonia water into the solution. The recovery of Ru, Y, Rh, Zr, Nd, Ce, La and Eu was found to be over 90%, while Mo, Ba, Pd, and Sr provided low recovery percentages.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.604-609
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• 1991

Antibiotic MT-497 was purified from the culture broth of Streptomyces nigr$^1H-NMR$ and composition of amino acids, MT-497 was identified as one of the actinornycin antibiotics containing actinocin chromophore and the peptide with threonine, proline, methyl valine, sarcosine and aspartic acid.

• Applied Biological Chemistry
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• v.19 no.2
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• pp.70-74
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• 1976

In order to study the mechanism of biosynthesis of thyroid hormones, radioactive iodine was injected into the rats and thyroid glands were removed. Iodine compounds hydrolyzed by pancreatin viokase were separated by paper chromatography and analyzed by radioautography. Radioautograms showed that the uptake of iodine starts immediately and forms diiodotyrosine through monoiodotyrosine. Evidence supported the possibility that diiodotyrosine is a precursor of thyrosine and triiodothyronine is a degradation product of thyroxine. The rat administered propylthiouracil showed inorganic iodine concentration activity, while the binding activity was prevented.

• Nuclear Engineering and Technology
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• v.5 no.3
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• pp.234-239
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• 1973

A recently known method of paper chromatographical separation of o-iodobenzoic acid-$^{131}$ I and o-iodohippuric acid-$^{131}$ I was found to be in error. The solvent mixture proposed in the method for the efficient separation of the two compounds of similar structure not only be made nonhomogeneous but also brings about no separation. It was also confirmed that no o-iodohippuric acid is converted to o-iodobenzoic acid during the process for Hippuran -$^{131}$ I preparation by isotopic exchange. Upon it, an alternate method of chromato-graphical determination of radiochemical purity of Hippuran-$^{131}$ I is proposed in present paper.