• 한국어류학회지
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• 제34권2호
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• pp.102-112
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• 2022

본 연구는 위내용물 분석과 안정동위원소(δ¹³C and δ¹⁵N) 분석을 통하여 우리나라 동해 북부 연안에 출현하는 명태(Gadus chalcogrammus)와 대구(G. macrocephalus)의 종내 및 종간 먹이자원 분할을 조사하였다. 두 종은 중층성 육식성 어종으로 명태는 저서성 및 중층성 갑각류를 주로 섭식하였고, 대구는 어류를 주로 섭식하였다. 위내용물 분석 결과에 대한 Non-metric multidimensional scaling (nMDS) ordination과 permutational multivariate analysis of variance (PERMANOVA)은 두 종의 종내 및 종간 먹이조성의 차이와 먹이자원 분할을 보여줬다. 안정동위원소 분석 결과 δ¹⁵N 값은 종간 유사하였지만, δ¹³C 값은 대구가 높은 값을 나타내어 두 종간 생태지위 차이를 보여줬다. 명태는 체장 증가에 따라 큰 체장군에서 새우류와 두족류를 더 많이 섭식하는 먹이 전환을 나타냈지만, 대구는 체장군 간 먹이조성이 유사하였다. 안정동위원소 분석에서도 체장군 간 차이를 보였는데, 두 종의 큰 체장군은 작은 체장군에 비해 더 높은 δ¹⁵N 값을 나타낸다. 결론적으로 본 연구는 명태와 대구의 위내용물 분석과 안정동위원소 분석을 통하여 종내 및 종간 먹이 차이와 생태지위 분할의 증거를 보여줬다.

• 한국광물학회지
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• 제19권4호
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• pp.383-392
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• 2006

도심에 위치한 탄산염암 석조문화재는 주로 대기 오염으로 인하여 흑색층이 형성되어 있으며 심하게 손상되어 있는 상태이다. XRF, XRD, SEM 등의 분석을 통하여 도심에 위치한 석탑 표면에 형성된 흑색층의 화학조성, 구성광물, 미세조직에 대해 연구하였다. 또한 흑색층이 원암에 끼치는 영향을 밝히고, 나아가 안정환동위원소분석법을 적용하여 흑색층 내에 함유되어 있는 황성분의 기원을 밝혔다. 석탑 원암의 구성광물은 방해석이지만 흑색층은 석고와 소량의 석영을 포함하고 있다. 흑색층을 구성하는 다량의 석고는 석탑 내부에 균열을 생성시키는 원인 물질이며, 흑색층과 원암의 경계면은 흑색을 띠는 것은 아니지만 그 특성이 흑색층과 유사하여 대기오염 물질을 쉽게 흡착하여 흑화될수 있다는 것을 보여주었다. 안정황동위원소분석 결과 흑색층에 함유되어 있는 황의 주 기원이 다를 수 있음이 밝혀졌다.

• Bulletin of the Korean Chemical Society
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• 제26권3호
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• pp.440-446
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• 2005

A method is described for the determination of dibutyltin (DBT) in sediment by isotope dilution using liquid chromatography inductively-coupled plasma/mass spectrometry (LC-ICP/MS). To achieve the highest accuracy and precision, special attentions are paid in optimization and evaluation of overall processes of the analysis including extraction of analytes, characterization of the standards used for calibration and LC-ICP/MS conditions. An approach for characterization of natural abundance DBT standard has been developed by combining inductively-coupled plasma/optical emission spectrometry (ICP/OES) and LC-ICP/MS for the total Sn assay and the analysis of Sn species present as impurities, respectively. An excellent LC condition for separation of organotin species was found, which is suitable for simultaneous DBT and tributyltin (TBT) analysis as well as impurity analysis of DBT standards. Microwave extraction condition was also optimized for high efficiency while preventing species transformation. The present method determines the amount contents of DBT in sediments with expanded uncertainty of less than 5% and its result shows high degree of equivalence with reference values of an international inter-comparison and a certified reference material (CRM) within stated uncertainties.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.777-782
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• 1999

It has been acknowledged that fertilizer and animal waste have different ratio of \ulcornerN/\ulcornerN which is presented as a symbol of $\delta$\ulcornerN, and that the values of $\delta$\ulcornerN for fertilizer and animal waste are placed less than +8 $\textperthousand$ and higher than +10$\textperthousand$, respectively. By this reason, the demarcation range for the source nitrogen mass ratio is between +8$\textperthousand$ and +10$\textperthousand$. In this study, we would suggest a possible method to trace the major pollution basis using the nitrogen isotope analysis method for management of water quality.

• 대한화학회지
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• 제62권4호
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• pp.265-268
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• 2018

The solvolyses of anthraquinone-2-carbonyl chloride (1) were studied kinetically in 27 pure and various mixed solvents. The analysis using the extended Grunwald-Winstein equation in the solvolyses of anthraquinone-2-carbonyl chloride (1) obtained the l value of $2.11{\pm}0.11$, the m value of $0.54{\pm}0.06$, and the correlation coefficient of 0.955. The solvolysis reaction of 1 might proceed via an associative $S_N2$ mechanism enhancing bond making than bond breaking in the transition state (TS). This interpretation is further supported by a relatively large solvent kinetic isotope effect (SKIE, 2.27).

• 한국세라믹학회지
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• 제35권11호
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• pp.1233-1239
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• 1998

Gas phase compositions of the hot filament-assisted diamond CVD reaction were analyzed by on-line quadrupole mass analysis(QMA) technique. D2 isotope experiments showed that methance molecules were decomposed into atomic state and then recombined in to acetylene during transport the probe line. Although acetylene or ethylene was supplied instead of methane similar gas compositions were obtained when filament temperature was above 1500$^{\circ}C$ Therefore this system could be assumed near thermal equilibrium state. Filament temperature and reaction pressure variation experiments exhibited the same tendency between acetylene concentration and diamond growth rate and these results implied that acetylene molecule played the role of the reactive species in the diamond CVD reaction.

• Nuclear Engineering and Technology
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• 제56권5호
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• pp.1762-1776
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• 2024

A spent nuclear fuel (SNF) analysis module for the Vodo-Vodyanoi Energetichesky Reactor (VVER) was developed and validated in this study. This advancement expands the application area of the existing nodal diffusion code, RAST-V, and reduces the need for additional code during 3D core simulations for SNF analysis, leading to increased efficiency in simulation time. RAST-V uses Lagrange interpolation and a power correction factor derived from the Bateman equation to bypass the re-depletion calculations, which are used to solve the microdepletion chain. This approach improved the efficiency of analysis. To mirror the conditions during the 3D core simulations, the module used history indices related to the moderator temperature, fuel temperature, and boron concentration. The module can predict 1620 isotopes. This paper presents the validation of this isotope inventory prediction and the application of burnup credit. The VVER analysis module was validated using 28 samples discharged from the Novovoronezh-4. Most isotopes were within 10 % of the boundaries of the measurements. This study successfully offers verification results using VVER benchmarks and discusses the application of burnup credit using a VVER-440 cask.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 추계학술대회 논문요약집
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• pp.205-205
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• 2003

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 2001년도 춘계학술발표회요약집
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• pp.391.2-391
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• 2001

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.443-444
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• 2005