• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 추계학술발표회요약집
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• pp.281.1-281
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• 2001

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2017년도 춘계학술논문요약집
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• pp.67-68
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• 2017

• Ocean and Polar Research
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• 제45권2호
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• pp.89-102
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• 2023

Climate and environmental changes in the Arctic Ocean due to global warming have been linked to extreme climate change in mid-latitude regions, including the Korean Peninsula, requiring a better understanding of the Arctic climate system based on the paleo-analog. This review introduces three paleoenvironmental research cases using neodymium isotopes (¹⁴³Nd/¹⁴⁴Nd, ε_Nd) measured on two different fractions of marine sediments: silicate-bound 'detrital' and Fe-Mn oxide-dominated 'authigenic' fractions. In the first case, detrital ε_Nd in core HH17-1085-GC on the continental shelf off northern Svalbard was used for tracing changes in sediment provenance and associated glacier behavior over the last 16.3 ka. The second case showed the potential use of authigenic ε_Nd as a quasi-conservative water mass tracer. Three prominent ε_Nd peaks and troughs observed in core PS72/410-1 from the Mendeleev Ridge in the western Arctic Ocean over the past 76 ka suggested episodic meltwater discharge events during 51~46, 39~35 and 21~13 ka BP. The last case proposed the use of the difference between authigenic and detrital ε_Nd as a proxy for reconstructing glacier fluctuation. The idea is based on the assumption that enhanced glacial erosion during glacier advances can supply sufficient freshly-exposed rock substrate for incongruent weathering, potentially leading to greater isotopic decoupling between bedrock and dissolved weathering products as recorded in detrital and authigenic ε_Nd, respectively. Thus, it would be worthwhile to take advantage of sedimentary ε_Nd to improve our understanding of past environmental changes in polar regions.

• 암석학회지
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• 제23권3호
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• pp.249-259
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• 2014

해수의 순환이 지구표면의 열 분배 및 궤도함수주기와 천년주기의 기후변화와 밀접한 관계가 있음이 알려지면서 과거 해수의 흐름을 지시할 수 있는 지시자의 개발이 관심을 끌고 있다. 이 논평에서는 해수 자생성 네오디뮴 동위원소 비를 해수순환의 지시자로 활용하는 원리와 분석방법 그리고 두 가지 적용사례를 소개한다. 먼저 지난 빙하기-간빙기와 아빙기-아간빙기에 걸쳐 북대서양심층수 세기의 변화를 명확히 볼 수 있는 예를 소개한다. 다음으로는 북극해에서 담수의 유입과 해수순환을 재구성한 예를 보인다.

• Nuclear Engineering and Technology
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• 제47권7호
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• pp.924-933
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• 2015

The correlation of the isotopic composition of uranium, plutonium, neodymium, and cesium with the burnup for high burnup pressurized water reactor fuels irradiated in nuclear power reactors has been experimentally investigated. The total burnup was determined by Nd-148 and the fractional $^{235}U$ burnup was determined by U and Pu mass spectrometric methods. The isotopic compositions of U, Pu, Nd, and Cs after their separation from the irradiated fuel samples were measured using thermal ionization mass spectrometry. The contents of these elements in the irradiated fuel were determined through an isotope dilution mass spectrometric method using $^{233}U$, $^{242}Pu$, $^{150}Nd$, and $^{133}Cs$ as spikes. The activity ratios of Cs isotopes in the fuel samples were determined using gamma-ray spectrometry. The content of each element and its isotopic compositions in the irradiated fuel were expressed by their correlation with the total and fractional burnup, burnup parameters, and the isotopic compositions of different elements. The results obtained from the experimental methods were compared with those calculated using the ORIGEN-S code.

• Nuclear Engineering and Technology
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• 제29권4호
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• pp.327-335
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• 1997

The correlation of isotope composition of uranium, plutonium and neodymium with the burnup in M uranium dioxide fuel has been investigated experimentally. The total and fractional($^{235}$ U) burnup were determined by Nd-148 and, U and Pu mass spectrometric method respectively. The isotope compositions of these elements, after their separation from the fuel samples were measured by mass spectrometric. The content of the elements in the irradiated fuel ore determined by isotope dilution mass spectrometric method using $^{233}$ U, $^{242}$ Pu and $^{150}$ Nd as spikes. The content of plutonium in the irradiated fuel was expressed by the correlation with uranium isotopes. The correlations between isotope compositions themselves and the total and fractional burnup ore compared with those calculated from ORIGEN2 code.

• Nuclear Engineering and Technology
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• 제33권4호
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• pp.375-385
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• 2001

The total burnup in the spent U$_3$Si/Al fuel samples from Hanaro reactor was determined by destructive methods using $^{148}$ Nd, the sum of $^{143}$ Nd and $^{144}$ Nd, the sum of $^{145}$ Nd and $^{146}$ Nd, and the sum of total Nd isotopes($^{143}$ Nd, $^{144}$ Nd, $^{145}$ Nd, $^{146}$ Nd, $^{148}$ Nd and $^{150}$ Nd) monitors. The fractional($^{235}$ U) turnup in the spent fuel samples was also determined by U and Pu mass spectrometric method. The samples were dissolved in a mixture of 4 M HCI and 10 M HNO$_3$ without any catalyst. The separation of U, Pu and Nd from the spiked and unspiked sample solutions was achieved by two sequential anion exchange separation methods. The isotope compositions of these elements, after their separation from the fuel samples were measured by mass spectrometry. The contents of the elements in the spent fuel samples were determined by isotope dilution mass spectrometric method(IDMS) using $^{233}$ U, $^{242}$ Pu and $^{150}$ Nd as spikes. The effective fission yield was calculated from the weighted fission yields averaged over the irradiation period. The difference between total turnup values determined by various Nd monitors were in the range of 1.8%.